Surgical procedures Flashcards
Fundoplication:
GORD on induction/emergence
-RSI (don’t bag)
-cricoid
-Extubate erect or lateral, fully reversed
-anti-emetics (Pre-emptive)
-High head up
Security to bed/pressure:
-lithotomy or foot pad, Tape arms w kimguard
-risk low cerebral perfusion; HTN so maintain his MAP
-art line, keep MAP within 20% of baseline
Bleeding risk (near IVC)- 2 big drips (pts G&H not valid)
Laparoscopy:
-issue in particular if IHD, vulnerable to lack of DO2 (reduced preload) & increased MRO2 (increased afterload) with laparoscopy
PTx risk
-watch CO2 & be alert to rises, airway pressures (set alarms just above the head-up pressure), watch BP- ready to ask surgeons to de-sufflate, level, fluid, vasopressor & PEEP
end of case, bring CO2 down with lung re-inflation
-Liver hook- deep paralysis, don’t want the pt to cough
-Pain (retrosternal) postop- consider PCA depending on extensiveness/PO tolerance
-?use of a bougie- extra paralysis/lignocaine in the mouth
ERAS principles
PROSTATECTOMY
SS_GG 1.9: For patients undergoing the following complex operations, discuss the specific anaesthetic management, including options for perioperative analgesia and perioperative fluid therapy: PROSTATECTOMY
-What are some considerations for robot-assisted laparoscopic radical prostatectomy (RALP)?
-What are the perioperative anaesthetic considerations for open simple & radical prostatectomy?
-What do rectus sheath blocks cover? How to perform?
-What do tap blocks cover? How perform?
-What’s the current consensus re: anaesthesia & Ca recurrence?
-What’s TURBT? Alternatives to anaesthetise? considerations?
Robot-assisted laparoscopic radical prostatectomy-requires 30deg trendelenburg & high-pressure pneumoperitoneum (moves abdo organs cephalad)
-chest band to prevent falls
-positioning considerations- patient access, lines free of equipment
-CNS: incr ICP, incr IOP (care re: optic neuropathy & corneal abrasion, avoid in pts w glaucoma) . risk of CNS irritation (transient postop confusion/agitation) w prol (2-3hr) head down &ICP; short-acting agents facilitate rapid postop heurolAx
-CVS: trendelenburg incr VR & CVP–> incr CO but pneumoperitoneum incr SVR which may reduce CO
-Resp: FRC & compliance decr–> atelectasis, V/Q mismatch, areas of shunt & hypoxia/hypercapnia- use PEEP but watch peak airway pressure (aim <35cmH2O), watch tube position when move head down . risk aw oedema, leak test prior to extubation
-GIT: risk gastro-oesophageal reflux- cuffed well-secured ETT, protect eyes
-risks of subcut emphysema, PTx or pneumomediastinum
-bladder is opened- excessive urine may disturb surgical field so restrict fluid admin for optimal surgical view (limit IVT to 1L until anastamosis complete, also may reduce risk airway oedema)
PROCEDURE for PROSTATECTOMY:
Duration 1-2hrs simple (pfannenstiel, T12), 2-4hrs (radical- lower midline; T10-12)
Blood loss up to 1L simple, 2L radical; X-match 2 units & have cell saver, common with this highly vascular area, poorly compressible
Pre-op considerations (risk identification & stratification, optimisation of modifiable risk factors w multi D team)
Consult: Simple prostatectomy is usually elderly & can be treated as TURP
Radical pts are usually relatively young & medically fit (it’s reserved for pts w localised prostate Ca & a life expectancy of >10yrs).
Need to Ax functional status, cardiovasc & pulm comorbidities
Check renal function, 12-lead ecg
Optimise: Hb- anaemia
smoking cessation
HTN and other modifiable CV risk factors
Planning/pre-med: likely cell saver, ensure blood available
Explain/consent, including discussion re: post-op pain & strategies
Disposition: HDU if radical
Intra-op:
Monitoring: art line, BIS, NMT, SpO2, NIBP 15-minutely, 5-lead ECG, temp probe IDC. Consider CVC if significant CVS disease.
Assistant: skilled anaes technician.
Drugs: prop TIVA induction/maintenance (+/- metaraminol infusion), ketamine 0.5mg/kg on induction, consider remifentanil or large fentanyl titrated, paracetamol pre-incision, vecuronium m relaxant (0.08-0.1mg/kg; 2.5-3mins, then 0.01-0.015mg/kg 20-40mins later (infusion 1microg/kg/min)), antibiotics 15-60mins pre-incision gentamicin (given urinary tract instrumented: for enteric GN bacteria, enterococci GP; bactericidal binds 30s subunit of bacterial ribosome impairing protein synthesis. Almost exclusively excreted by glomerular filtration; 2-3hr t1/2 if N renal function, 20-40x longer in renal failure. 2mg/kg IV, give over 3-5mins, dosing is on actual body weight for lean, obese use dose determining weight (IBW + (0.4x (abw-IBW)). Avoid in pts with significant pre-existing hearing loss or vestibular problem, avoid if hypersensitivity to aminoglycosides, myasthenia gravis or severe renal impairment. Risk ototoxicity, nephrotoxicity, skeletal m weakness, potentiates NMBDs (can overcome w Ca++)). Also give cefazolin 2g. if risk enetering bowel, metronidazole. if risk mrsa vanc.
-Analgesia: there’s lack of consensus re: optimal regimen.
-Penile block not shown in RCTs to improve bl catheter tolerance
-intravesical ropivacaine not ass’d w improved pain control
-multimodal strategy including regional should be employed; regional ass’d w lower postop pain scores, reduced blood loss & shorter duration of surgery.
PROSPECT guidelines for prostatectomy for cancer:
-apply to open, laparoscopic & robotic; robotic & lap decreased pain levels cf open (radical= moderate dynamic pain in immediate postop days)
-NSAIDs & COX-2 selective inhibitors lower postop pain scores for open surgery; Parecoxib (if renal or cardiac function permits); COX-2 selective lower risk bleeding cf nonselective -IV lignocaine infusion reduce postop pain, morphine consumption & LoS for open surgery -LIA improves pain scores for open surgery -bilat TAP blocks at the end of surgery lower pain scores for robot-assisted procedures, results conflicting for open (& poor study designs) & state that rectus sheath block has lack of procedure-specific evidence (despite only stating one study for radical prostatectomy that found pts with rectus sheath block had lower pain score & opioid use postop day 1). -must have paracetamol & NSAIDs or COX-2 selective (unless CI) as basic analgesia -TAP blocks first-choice regional for laparoscopic/robotic radical prostatectomy -IV lignocaine considered for open surgeries but it’s use contraindicates the simultaneous use of LIA. Insufficient evidence for lignocaine in minimally-invasive surgery. -if doing open surgery, should use wound LIA in pref to other regional blocks (eg. rectus sheath cath), if not using IV lignocaine infusion -opioids should be rescue postop -use dexamethasone & paracetamol (despite lack of procedure-specific evidence)
-likely post-op PCA (visceral pain)
-consider pre-op gabapentinoids (as per PROSPECT, limited procedure specific evidence, side effects (sedation, drowsiness, blurred vision))
-PROSPECT do NOT recommend intrathecal opioids (however at our institution we sometimes use 150microg ITM, discussing complications of PONV, pruritis, OIVI, urinary retention- ITM reduces opioid requirements & N&V, can still use PCA if pt going to ICU w careful surveillance. although the studies in their review only discussed non-sig incr pruritis, they stated that the adverse effects are dose-dependent (n&v, resp depression) & that low doses haven’t been documented as effective after prostatectomy + they state that the duration of analgesic effect isn’t clear after spinal morphine; APMSE: for major abdo or Tx surg, IT opioids combined w GA, using ITM 100-500mcg (should use max 300) reduces pain scores @ rest & movement up to 24hrs, opioid-sparing for up to 48hrs, more pronounced for abdo vs Tx surgery. aftrer prostatic surg, ITM is better analgesia & lower opioid requirements up to 18hrs.) or epidural (despite only saying the epidural was ass’d w lower pain than PCA) due to risk of adverse effects; they state in general to avoid Tx epidural due to invasiveness, risk of side effects & complications such as hypotension, dural puncture & epidural haematoma. APMSE: TEA has improved cough pain & opioid requirement & preserved exp m strength but incr LoS w TEA. TEA had no impact on blood loss or transfusion rate. ?TEA may be ass’d w incr malignancy recurrence? no evidence of benefit over systemic analgesia
GA technique doesn’t have procedure-specific evidence. No procedure-specific evidence for dexamethasone, ketamine, Mg++, clonidine, pregabalin.
A: cuffed ETT
B: IPPV, lung-protective
C: art line, large-bore IVC x2, ensure valid group & hold + have cell-saver, Hb & coags pre-op, vasopressors & focus on cardiostable induction
D: BIS 40-60, NMT so adequate relaxation, maintenance propofol TIVA, BGL monitoring
E: pre-warm, normothermia, supine with vulnerable (eg. Eyes) & pressure points padded & protected (prolonged case)
F: excess urine may confound surgical view (bladder open).
Goal-directed for major surgery w EBL >500mL
If no other reason to be selective w fluid, balanced crystalloid aiming for intra-op normovolaemia; recognise & manage hypovolaemia which may compromise organ perfusion (composite of resp variations in intra-art pressure waveform, SvO2 & lactate; PPV <10% & ensure volume status optimal before adding vasopressor) but excessive fluid risks tissue & organ oedema, incr LoS, infectious postop complications + anastamotic leakage.
Pre-op bolus if hypovolaemic (eg. 8mL/kg on induction).
Balance lost blood w crystalloid 1.5:1 or colloid 1:1 until reach transfusion threshold.
Potential complications:
Air embolism
Bleeding
Infection
Pain
Postop:
Recovery: keep warm
Analgesia: likely PCA +/- LIA or rectus sheath catheters (epidural not recommended by PROSPECT due to complications in other pt groups) & pt may have had ITM despite lack of evidence re: efficacy of analgesia w lower doses & side effects pruritis w higher doses but APMSE says for major abdo surgery ITM improve pain scores & reduce opioid req’t (up to 18hrs for prostatic surgery).
Disposition: HDU if radical
Follow-up: APS
Anteromedial abdominal wall & periumbilical areal (T9-11), anterior cutaneous branches of intercostal nerves
US transverse above umbilicus, 1cm lat to midline
Needle in-plane through RA, tip btwn muscle & posterior rectus sheath. 10-15mL 0.375% ropivacaine. Perform bilaterally.
Fascial plane block (relies on volume/spread), covers the intercostal, subcostal & L1 segmental nerves which communicate to form the upper & lower TAP plexuses, innervating the anterolateral abdominal wall incl parietal peritoneum (?is this why good for robotic prostatectomy- port pain)? The subcostal (upper) tap block ideally anaesthetises T6-9, lateral tap in midaxillary line btwn Tx cage & iliac crest should reach T10-12. L1 requires an anterior TAP, medial to the ASIS.
Subcostal: probe transverse @ subcostal margin, lat-medial in-plane LA above TA (spreads under RA, linea semilunaris & IO).
Lateral tap: probe transverse in MAL, get all 3 m layers & inject btwn IO & TA.
-lab, animal & retrospective human data suggest that anaesthetic agents may impact Ca recurrence but there’s insufficient evidence to suggest a specific agent or technique to reduce Ca recurrence in pts undergoing Ca surgery.
-periop period ass’d w multiple factors that may influence tumour cell survival (inflam & stress responses, relative immunosuppression, potential direct effects of anaes/opioids).
-potential role of agents: VA= may impair host defence; pro-inflammatory & immunosuppressive, upregulation of hypoxia-inducible factors (which stimulate protumorigenic Bx & contribute to malignant cell proliferation/ Ca recurrence), inhibit monocyte phagocytosis & tumoricidal activity eg. inhibit NK cells. Propofol anti-inflammatory & antioxidative effects that protect against immunosuppression & may preserve NK cell activity.
-Mast cell activation from morphine may accelerate Ca progression, oxycodone & morphine may reduce NK cell activity.
-Regional may reduce Ca recurrence by reducing need for opioids/volatiles & reducing stress response to surgery.
-Strong in vitro evidence re: protective effect of systemic lignocaine for Ca recurrence.
-Spinal vs GA= higher 5-year survival for pts undergoing TURBT
-LAs (lidocaine & ropivacaine) have anti-metastatic effect.
liver trauma
liver= most frequently injured abdo organ (in blunt abdo trauma.
most injuries heal spontaneously or heal w arteriography/embolisation (hepatic embolisation requires interventional radiologist experienced with celiac artery catheterisation & embolisation & facilities, efficacy of angioembolisation in hepatic trauma is 93%. is most successful when used preemptively in haem stable pts).
liver dome as high as T4 w expn, low as T12 w deep inspn. Posterior portion of R) lobe= most common site of hepatic injury in blunt trauma.
Resus, evaluate & Mx as per ATLS, haem unstable–> immediat OT transfer. FAST exam (hypoechoic ring of subcapsular fluid intraperitoneal fluid, fluid in Morrison’s pouch), diagnostic peritoneal aspirate (useful if FAST equivocal; negative FAST doesn’t exclude liver injury) or CT (which confirms injury & defines grade) may be performed.
CXR w R)-sided rib fractures incr suspicion for liver injury
Hepatic injuries graded as per AAST, predicts likelihood of success of nonoperative Mx (higher for grade I-III)
-grade I: subcapsular haematoma <10% surface area, parenchymal lac <1cm depth.
-grade II: subcapsular haematoma 10-50%, intraparenc haem <10cm, lac 1-3cm deep & <=10cm long.
-grade III: subcapsular haematoma >50% surface area, ruptured subcapsular or parenchymal haematoma, intraparenchymal haematoma >10cm deep, lac >3cm deep, any liver vascular injury or active bleed within liver parenchyma.
-grade IV: parenchymal disruption involving 25-75% of a hepatic lobe, active bleeding extending beyond liver parenchyma into peritoneum
-grade V: parenchymal disruption >75% of a hepatic lobe, juxtahepatic venous injury to include retrohepatic vena cava & central major hepatic veins
Initial surgical management of haem unstable pts w liver injury= damage control techniques, temporary control of bleeding allowing us to resuscitate, eg. if portal triad injury, control hepatic artery or portal venous bleeding (eg. with pringle maneouver (encircle hepatoduodenal ligament w vascular clamp +/- rommel tourniquet)); vital since average of 1L blood flow/min, expose triad w wide Kocher maneouver, repair portal vein where possible. If 2nd look OT, typically within 48hrs (earlier if concern for bowel ischaemia.
Postop, surveillance for portal venous thrombus (33% who had portal venous repair get portal venous thrombus).
Hepatric artery injured less commonly, if it’s ligated then gallbladder should be removed (since GB blood supply diminishes ++).
severe injury to the liver may require resection to manage bleeding or remove ischaemic or dead tissue.
grade IV packing, reboa or rebov
Breast surgery & breast reconstruction
PROCEDURE:
breast-conserving Rx (eg. WLE with radiotherapy or chemo) means that radical mastectomy is less common but contraindicated in inflamm breast Ca, multifocal disase & in pts w prior breast radiation.
radical mastectomy is done for tumours invading pecs muscles.
some pts elect for prophylactic mastectomies.
SLNB tends to occur for staging (vs ALND which has more adverse effects & equal efficacy).
SLN= the first node(s) draining from primary Ca so is the most likely to contain metastatic disease.
the node mapping occurs w combo of radio-isotopes & dye injection near tumour during OT for r/o primary Ca. LNs w highest radioactive signals are removed.
pts w +ve SLNB may require subsequent ALND w further adjuvant Rx (risks of ALND incl lymphoedema, UL sensory loss, incr hospital LoS & slower return to function).
SLNB uses patent Blue which is ass’d w IgE-mediated anaphylactic reactions, overall anaphylaxis risk 1%!! (0.17% for more serious reactions). patent blue V dye= 4th morst common cause periop anaphylaxis as per NAP6. Methylene blue may be safer wrt anaphylaxis but interference w pulse ox (absn peak close to reduced Hb so falsely low pulse ox) & skin discolouration.
RECONSTRUCTION:
all pts having mastectomy offered breast recon @ the time or as delayed procedure (more often done immediately for non-invasive cancers & risk reduction surgery)
either implant-based (often saline TEs under pecs initially rradually incr in size then definitive silicone implant- 30% have complications requiring further surgery within 5 yrs) or autologous flap recon using pts own tissue (skin, fat & sometimes part of underlying muscle- longer initial surgery but may be ass’d w reduced number of OTs, lower complications & often a more natural aesthetic), either pedicled (eg. lat dorsi) or free (division of vascular pedicle, blood supply re-established using MICROVASCULAR surgery (hence requires specialist plastic surgeons)). Most commonly transverse rectus absominis myocutaneous (TRAM) which is pedicle, lat dorsi if TRAM not suitable (eg. high risk of failure due to DM or smiking) of free flap is DIEP. The latter preserves rectus abdominis muscle which helps preserve abdo strength & halves likelihood of bulge or hernia & shortens recovery time. Pedicled flaps also more painful.
DIEP involves:
1. raising flap, meticulous separation of small perforator vessels oroginating from deep inferior epigastric artery
2. microvascular anastamosis to internal mammary artery & vein in chest
3. insetting of the flap & shaping the transferred tissue
gold standard in free flap breast recon= deep inferior epigastric perforator free flap
Pre:
pt selection & preparation = predictor of good clinical outcome in microsurgery:
-smoking cessation (hypercoaguability, vasoconstriction from nicotine, CO-related tissue hypoxia may–> impair ooutcomes).
-weight loss if obese
-absolute contra-indications for microsurgery: hypercoaguable eg sickle cell anaemia, polycythaemia (risk anastomotic thrombosis).
Hematopoietic adverse effects of neoadjuvant therapy: myelosuppression (anaemia, thrombocytopaenia bleeding risks, neutropenia sepsis risk); MYELOSUPPRESSION USUALLY REVERSES WITHIN 6/52 of CHEMO, still useful to send crossmatch. hormonal agents eg. tamoxifen (oestrogen recptor modulator), aromatase inhibitors (block aromatase converting other hormones into oestrogen), monoclonal antibody Herceptin for HER-2 positive tumours. These agents can be cardiotoxic (cardiomyopathy) & incr risk periop VTE.
-long surgery: require >4METs
-Ca pt; 4M’s eg. cyclophosphamide & doxorubicin= cardiotoxicity even years after the initial chemo (eg. CM, prol QT) so assess these pts for Sx of cardiac dysfunction before surgery (& Ix incl ECG or echo)
-clinic opportunity to counsel, allay anxiety
Intra-op:
pre-op anxiolysis as needed
A, B: for recon, cuffed ETT, lung protective vent (prolonged surgery)
normoxia (hypoxia= catecholamine release & vasoconstriction, hypocapnia= vasoconstriction, hypercapnia= SNS stimulation)
mastectomy generally SGA
C:
-large PIVC opposite side to surgery (may have undergone axillary Cl, risk lymphoedema); CVC if very prolonged or sig chemi-impaired venous access, foot if bilat procedure
art line
-during dissection phase, controlled hypoT may be requrested (achieve w prop/remi but not VDs as may promote flow steal away from flap). during anastamosis, normotension to ensure adequate perfusion pressure. vasopressur use controversioal- inadequate evidence to suggest it impacts outcome; phenylephrine & ephedrine in adequately filled pts apperas safe.
-to optimise flap perfusion, full hyperdynamic circulation, high CO, peripheral VD, large pulse pressure, normothermia
utilise principles of Hagen-Pouiselle:
blood flow = ((pi . deltaP x r4 )/ (8xviscosityxl))
manipulate pressure gradient (systemic arterial pressure minus venous pressure)
vessel radius
blood viscosity (optimal hct to blanace viscosity, flow & O2-carrying is 30-35%)
ensure MAP adequate for perfusion:
promote appropriate vessel calibre: warm pt, normovolaemic (normovolaemia allows decr viscosity & decr PVR & incr CO which improve tissue Q. fluid overload promotes oedema while hypovolaemia compromises perfusion, low SVR, good peripheral perfusion; use goal-directed fluid therapy eg. oesophageal doppler monitoring, to guide crystalloids & colloids (eg. monitor effect of fluid on SV, aim SVV <10%)
Transfusion rarely required unless mastectomy w immediate recon esp if bilat
anticoagulation: VTE is a risk; pharm/nonpharm
(subcut proph heparin improves flap survival, TEDS, SCDs)
D:
-supine, ULs abduction <90deg (care BP injury risk, forearms neutral to prevent ulnar n injury). Careful positioning for long procedures, prevent peripheral nerve damage & pressure sores; heel pads, pillow under knees to stop painful hyperextension. Consider passively moving joints throughout procedure & @ end (procedure may be 6-10hrs).
Lat dorsi recon lateral, ETT.
-TIVA maintenance favourable for PONV & quality of recovery but emergence may be prol after long infusion.
remi or fent boluses; remi helps limit use of NMBD
-analgesia: 2 operative sites (chest & lower abdo). ?free flap breast recon chest site MAY be less painful vs mastectomy as flap insensate, lack of tissue stretch when flap used for wound closure. abdo (donor) site more painful. TAP blocks reduce postop opioids up to 48hrs. @ induction under US or by surgeons or US @ end (catheters advantageous).
systemic postop analgesia: paracetamol, NSAIDs, prn opioids (PCA/orally but short-acting).
adequate analgesia important to limit SNS surges compromising flap survival.
tPVB: for mastetomy w ALN dissection, perform btwn T-&T5. 15mL usually prouces somatic spread over 3 dermatomes, for larger spread, multiple injections of 3-5mLs may be needed.
tPVB have some minimal effect on intra- or postoperative opioid consumption & PONV. Either single-shot or placement of a catheter= less acute pain in the first 72hrs postop. tPVB for acute postsurgical pain may protect against chronic postsurgical pain after breast surgery @ 6/12, evidence is limited. Complications rare: potential for intra- and postoperative hypotension secondary to epidural spread of LA.
TEA: rarely used, technical difficulty & high (20%) failure rate. risk hypotension.
PECS I (0.2mL/kg long acting LA) & II (0.4mL/kg): interfascial, described 2012, PECSI= med & lat pectoral nerve, II= lateral branch of intercostal nerve, intercostobrachial long thoracic. this provides axilla blockade & IC neerves, wider area of incision covered.
Need US, lat 1/3 of clavicle in oblique plane, needle advanced btwn pec maj & minor @ level of R3. adjust probe to visualise R4, redirect needle to deeper plane between pec minor & SA.
Fast, no SNS block, can do under GA. less postop pain & opioid requirement cf GA alone.
RCT comparing single-shot TPVB vs PECS for mastectomy under GA showed PECS delivered longer analgesia & less opiod consumption! PECSII gives benefit of axillary analgesia as unlike TPVB, it blocks long Tx nerves.
SAP: described for breast in 2013. lat cuteneous branches of Tx intercostal nerves T2-12, analgesia for anterolateral chest wall. LA in-plane, deep to LD & superficial to SA in mid-axillary area @ level of R4 or R5. 0.2mL/kg long acting LA.
Also rapid, can be done under GA, like PECS no neuraxial block or risk Horner’s, either are suiged to day cases.
transverse thoracic plane: LA btwn transverse thoracic & internal intercostal muscle @ level of R4 or R5, anteriorly, @ costosternal junction. aims to anaesthetise anterior branches of intercostal nerves T2-6, analgesia for internal mammary region. may supplement PECS I & II w additional medial analgesia.
E,F:
recon: temp probe IDC monitor temp, actively warm (pre-warm, under & over body warming intra-op, warm OT, warm IVT, humidified gases) & euvolaemic status
other breast OT: temp monitor if >30min or warmer
Emergence:
?prior to end of procedure surgeon may request sit pt up to Ax symmetry??
cough & retch incr venous pressure & reduce flap flow so smooth extubation (eg. remi w deep extubation or exchanging tube ofr SGA)
Post:
Free flap require general & flap monitoring in HDU at least 24hrs, continue flap monitoring for several days.
Minor procedures, incl WLE w SLNB, should be ok for day-case if pt/surg/facility factors allow
monitoring for potential complications:
-impaired flap viability: recognise changes in perfusion rapidly & manage quickly to optimise chances of successful salvage.
viability impaired by: primary ischaemia as blood flow ceased during flap bransfer (anaerobic met, lactate, acidaemia, incr Ca++ & pro-inflammatory mediators). severity prop to duration. since O2 consumption of skin is 5x < muscle (0.2mL/min vs 1mL/min per 100g tissue), TRAM flaps (w skeletal muscle) are more sensitive to ischaemia than DIEP.
reperfusion= second important phase, after microvascular anastamoses, vessels are unclamped, blood flow restoration generally reverses physiological changes of primary ischaemia but may be isch/reperfusion injury if prolonged ischaemia or inadequate perfusion pressure & influx of inflammatory substances that may comproise the flap. risk of secondary ischaemia more harmful to flap than primary ischaemia; risk intravascular thrombosis & interstitial oedema. DIEP can tolerate 10-12hrs ischaemia but irreversible changees if TRAF flap after only a few hers.
microcirculation (arterioles, capillaries, venules) has feeding artery & draining vein that lose intrinsic SNS tone when denervated but still respond to physical, humoral & chemical stimuli (eg cerculating catecholamines, cold); absence of lymphatic drainage incr risk of interstitial oedema in the flap. NEED TO MAKE SURE MEASURES TO OPTIMISE TISSUE PERFUSION INTRA-OP ARE CONT’D POSTOP: warm, MAP/CO, hyeprdynamic circn, normovolaemia, hct 30-35, analgesia to limit SNS VC.
limit oedema, hypercoagulable states.
monitor clinically: staff caring for these pts need to recognise an ischaemic flap:
-auditory w 8MHz transcut doppler (probe on skin over perforator BV on the flap).
-colour
-cap refill
skin turgor
skin temp
bleeding on pinprick
arerial ischaemia= cool pale flap w slow cap refill, no bleed on pinprick, loss of triphasic art doppler signal.
venous cause= warm/congested/bluish flap w brisk cap refill, rapid bleed of dark blood, loss of venous doppler signal (continuous sound)
if recognise within 6hrs, 75% salvage rate.
re=exploration. anaes conditions to optimise flap flow.
infection
postoppain (incl chronic)
cancer recurrence: retrospective analyses & lab studies suggest anaesthetic technique may influence Ca recurrence but there’s a lack of prospective, randomised trials proving causal effect. of interest since recurrence of breast Ca occurs in 30% of cases & mortality in breast Ca is more often from recurrence vs the primary tumour.
opioids inhibit NK cells & stimulate Ca cell proliferation (angiogenesis & tumour cell signalling pathways promoted)
Nephrectomy
PATIENT:
-often elderly population (eg. renal cell carcinoma commonly presents in pts >70yo), higher burden of comorbidities (evaluate for cardiovasc, resp, cerebrovasc disease), higher risk complications
-for those w high OT risk, sig renal impairment or small cortical tumours (<3cm), RFA may be considered
PROCEDURE:
Partial nephrectomy may be considered if well-localised tumour (eg. <7cm) as similar oncologic outcomes cf readical neph w sig less risk chronic renal dysfunction, multiple tumours or suspect will need further future surg or if pt has only 1 kidney (blood loss may be large in partial nephrectomy as vessels harder to control), otherwise radical (eg. spread to adrenals or renal vein or perinephric fat)
Open nephrectomy may be indicated for large tumours or polycystic kidneys.
paramedian or transverse incision for a tumour, a loin incision with retroperitoneal approach for other pathologies or donor nephrectomy.
Discuss size of tumour & extent of OT w surgeons; thoracotomy may even be indicated.
For minimally invasive nephrectomy there’s a smaller more anterior subcostal incision (less postop pain & shorter hospital stay vs open but more pain & longer stay than lap. Lap not associated with increased complications)
often 1-2.5hrs, supine or lat decubitus, consider pressure sore, nerve damage risk, venous congestion
If robotic, considerable space required in OT
protect pts: eg. head from unexpected collisions w robot arms, pt movement may–> tissue injury during robot docking so NMB vital
robot docking may disturb pt Ax & Mx in emergency
after nephrectomy they may consider adj chemo if high risk recurrence
PATHOLOGY:
pt may have symptoms from tumor itself (eg, mass, pain), invasion of the urinary tract (eg, hematuria), paraneoplastic syndromes (eg. ACTH-like, PTH-r peptide, renin/glucagon/insulin, renal tumour may cause inappropriate ADH secretion (normal/high plasma vol, hyponatremia, low serum osmolality, high urine osmolality & Na, low or normal urine volume)), or the presence of metastases (kidney tumour may be associated with lung mets/pleural effusion, brain mets)
renal tumors may cause anaemia without bleeding; for RCC anaemia may preced Ca Dx, may be disproportionally severe, may be normo- or microytic, Fe studies consistent w ACD
Pts may have cachexia w RCC
POTENTIAL COMPLICATIONS:
impacts of pneumoperitoneum, volume status, MAP, surgical manipulation on renal perfusion & postop renal impairment or success of renal transplant
bleeding
usual infection, posotp resp complicaitons related to pain
PRE (risk identification & stratification, optimisation of modifiable risk factors in liaison with multi-D)
-aggressive smoking cessation: reduces resp complications, promotes wound healing, ideally 4/52 preop (this is the threshold to reduce post-op resp complications. any helpful- 12hrs CO eliminated, quitting 1 day reduces licotine (VC, SNS) & COHb levels, improves DO2. 2/52 incr sputum prod& cough but good thing (resp defences), 4/52 resp comp, 6-8 sputum normalises & analgesia req’ts normalise & PFTs improve, 6 months improved immune function).
-correct Fe deficiency with or without anaemia: recommended if predictive blood loss >500mL, incr incidence of blood transfusion ass’d w postop M&M (while PREVENTT showed that IV Fe wasn’t superior to placebo for pts with anaemia 10-42 days before elective major abdo surgery (wrt blood transfusion or death in periop period, also secondary outcomes of average amount of blood given, adverse outcomes/LoS, QoL but there were less unplanned readmissions & postop infection n Rx group)- issues with the trial eg. pts were screened & treated based on anaemia vs Fe def, their threshold for anaemia was high (M <130, F <120), transfusion thresholds unclear.
-frailty (an age-related state of vulnerability to stressors incl surgery/illness, ass’d w adverse outcomes incl M&M, hospital admission & incr LoS, falls, disability, need for long-term care. Can quantify with multiple scales incl: edmonton frail scale, encompasses 14 questions over 5 domains: cognition, general health, function, social support, nutrition. FRAIL: fatigue, resistance (walk flight stairs), ambulation (walk 1 block), illnesses, loss of weight (>5% body mass in 1 yr). Or Fried 5 frailty indicators: weakness, slow walking speed, low physical activity, self-reported exhaustion, unintentional weight loss. Ax (eg. Ca cachexia for RCC), consider prehab.
-medication advice
-HTN optimisation (can be ass’d w renovascular disease with other comorbidities related to HTN (CVD, CVA))
Consider indication:
-4M’s (esp lung mets/pleural effusion)
Check BP; renovascular disease ass’d w HTN
-Labs: Hb (renal tumours may cause anaemia without bleeding), estimate residual renal function
Check electrolytes- renal tumour may cause inappropriate ADH secretion (low serum Na+, osmolality), non-functioning kidney or renovascular disease ass’d w renal impairment, Ca++, glucose
Check CXR (pleural effusions/METs)
check ecg (eg. signs of LVH if renovascular disease & HTN)
INTRA (risk mitigation)
A: ETT (need for m relaxation, need to control ventilation to control EtCO2 w insufflation & mechanical effects of pneumoperitoneum, time, risk blood loss, position may be lateral)- lung-protective ventilation PCV (with VG for pneumoperitoneum) but tolerate mild hypercapnia (ETCO2 45mmHg)
B: IPPV
C: 2x large-bore IV, G&S/X-match
bleeding varies- 300mL-3L+!
depending on extent of any tumor (eg. extension into IVC higher risk blood loss- clear communication w surgeons (eg. re: haemodynamic changes), they may consider IVC XC temporarily to control bleed. For such tumours have colloid, blood (checked & ready), vasoconstrictor & an inotropes ready with pressure bag for fluid if predicting large blood loss)
Consider cell salvage
If anything but an uncomplicated non-malignant nephrectomy or small isolated tumor, have blood warmer, CVP & art line. Invasive monitoring not indicated for living kidney donors but 2x large-bore IVC is- significant bleeding occurs in 0.1-0.45% of live donors.
Consider effects of position & pneumoperitoneum on renal perfusion (esp important if live donor)
Optimise renal perfusion during lap nephrectomy with:
-Low insufflation pressures <15mmHg during laparoscopy
-IV volume expansion to ensure UO >1mL/kg/hr (live donor may receive 4-6L isotonic fluid during laparoscopic nephrectomy to counteract the effects of gas insufflation during laparoscopy)
-to manage MAP, give fluid first, limit vasopressors (avoid pure alpha agonists) as they limit renal perfusion- ephedrine first line if fluid inadequate to maintain MAP, NAdr if refractory (@ 1-30microg/min (0.01-0.3microg/kg/min); mix 6mg to make 100mL in glucose 5% (final [] 60microg/mL), so 1mL/hr is 1mcg/min)
-tolerance of mild hypercapnia (45mmHg) as this promotes VD, cardiac output & rightward shift of O2-Hb dissociation curve which may all optimise renal perfusion & tissue oxygenation
for a kidney being resected for renal transplant main risk= kidney ischaemia, limit by maintaining renal perfusion: preserve intravascular volume, ensure adequate MAP, avoid high intra-abdo pressures
Kidneys from living donors have better graft & pt survival for the recipient kidneys than deceased donors as live donors physiologically & haemodynamically normal with kidneys not exposed to ischemic alterations ass’d w brain or cardiac death
warm ischaemia time 60mins
cold ischaemia time 18hrs DBD, 12hrs DCD
Can electively schedule the transplant @ same facility so less cold ischemia time, ideally transplant from a living donor is preemptive so the recipient avoids complications of dialysis
To maintain renal perfusion prior to clamping of the renal artery (limit subsequent ischaemia), some surgeons may request mannitol 12.5-25g, frusemide 5-10mg +/- heparin 3000IU to maintain urine output >1mL/kg/hr during times where risk to RBF. Cooling with ice may also limit ischaemia.
D:
drugs:
Short-acting opioid for laryngoscopy
TCI as antiemetic
NMBD
avoid N2O- may cause bowel distension interfering with surgical view, contributes to PONV
Avoid nephrotoxics to preserve function of remaining kidney
E:
Warm, monitor temp (bleeding risk)
F: aim urine output >1mL/kg/hr, particular care w fluid balance & BP perioperatively if pre-op renal impairment.
G:
H: bleeding risk (see C)
I:
J:
K:
L:
M:
Standard ANZCA monitoring + BIS, NMT, consider art line, consider CVC if expect large blood loss, DO monitor UO eg. hourly tally intra & postop, temp probe (IDC)
N:
O:
P:
Pain: surgical incision-all approaches painful
For loin incision need analgesia of T7-8
?thoracic epidural for open or minimally invasive nephrectomy (minimal dosing intra-op (eg. just opioid) to take care w hypoT but needs high block postop) or continuous ESP block/PVB/intercostal blocks
Rectus sheath catheters for anteromedial abdominal wall, cover T9-11, anterior cutaneous branches of intercostal nerves
generally avoid NSAIDs (nephrotoxic) in elderly or if poor renal function or hypovolaemic BUT opioid sparing (less post-op pain, LoS) so cosider carefully
or PCA
lap nephrectomy: port site insertion, abdo incision, organ manipulation, diaphragm irritation or ureteral colic may cause postop pain
Intraop IV Dex, paracetamol, subfascial bupivacaine (eg. TAP block), ?ESP blocks preop?
Postop IV PCA, paracetamol, ?pregabalin 150mg BD on day of surg & on first postop day
position supine or lateral (“kidney position” for loin incision, pt lateral & extended over a break in the table, axillary roll to limit compression injury to axillary structures/brachial plexus injury)
pressure areas
venous congestion risks
protect eyes & ears, neck neutral
marked fall in BP is common on assuming this position due to reduced venous return from the legs and possible IVC compression. Further compression during surgery may result in a severe reduction in venous return and CO.
POSTOP (complications surveillance)
-pulm compilcations if open, esp if subcostal lateral incision
-consider postop ICU if high bleeding, sig comorbidities incl pre-op renal impairment
port site insertion, abdo incision, organ manipulation, diaphragm irritation or ureteral colic may cause postop pain
Intraop IV Dex, paracetamol, subfascial bupivacaine (eg. TAP block), ?ESP blocks preop?
Postop IV PCA, paracetamol, ?pregabalin 150mg BD on day of surg & on first postop day
Cystectomy
PATHOLOGY:
OT indication for radical cystectomy= nonmetastatic muscle-invasive bladder Ca or for pts with locally advanced or metastatic bladder Ca who have major response to cisplatin-based chemo
Pt (& preop): risk identification & stratification, optimisation of modifiable risk factors in liaison with multi-D team
Metabolic effects: cancer cachexia, consider pre-habilitation in liaison with dietetics (optimise nutrition), physio, physicians; assess frailty & functional status
Meds: cisplatin causes renal impairment, diarrhoea, haematopoietic effects
Mass effects:
Metastases: lungs, bone, brain
General anaesthetic & medical:
cardiovascular, respiratory (eg. COPD)
renal function, FBC, Fe studies
pre-op counselling
PROCEDURE:
Open or minimally invasive (laparoscopic or robotic)
remove bladder & organs @ risk of harbouring tumours & regional LN
Ureters mobilised & divided, bladder freed & urethra transected.
removal of other organs varies (consideration of sexual-preserving techniques), standard radical cystectomy includes: prostate, seminal vesicles, distal ureters, regional LNs (often causes impotence). Women radical (aka ant exenteration)= r/o bladder, urethra & adj vagina, uterus, distal ureters, regional LN.
urinary diversion eg. ileal conduit (ideal reservoir would be low pressure, hold adequate volume (500mL), have continence, minimise absorption & metabolic complications), or neobladder with intestinal tissue.
PROLONGED (3-5hrs, longer with bl recon), position lithotomy w head down
postion/pressure areas, IPPV w ETT & LPV
POTENTIAL COMPLICATIONS & intra-op (risk minimisation) & postop (complication surveillance) strategies
Many of these can be mitigated by ERAS pathway, multi D & multimodal interventions spanning pre- intra- post, to optimise pt satisfaction, earlymobilisation, limit periop compliations & promote early discharge
Ileus: limit through implementation of ERAS, eg:
first on list, limit fasting time
carb loading
early PO intake
use of NGTs rare (d/w surgeon)
early mobilistion (analgesia, anti-emesis, physio)
minimally invasive OT if pt/path/surgeon allows
careful fluid balance: use UO +/- CVP to monitor (can be challenging to onitor UO with conduit whichis positional, neobladder may have multiple drains), balanced crystalloids, err towards restrictive depending on UO & renal function but euvolaemia to ensure organ perfusion (watch MAP, SVV) & may be considerable intra-op losses & intraperitoneal loss/ileus
leaking anastamosis: confirm w finding of urine in abdo drain, compare biochem of fluid from drain vs conduit
Cardiovascular:
pneumoperitoneum if laparoscopic, careful monitoring
air embolism possible (w any major open pelvic surgery)
electrolyte impalance & renal injury:
monitoring for hyperkalaemia is important when the ureters have been clamped before urinary diversion
also want to reduce volumes of fluids for cystectomy to reduce volume overload & the incidence of renal injury if there’s a significant delay between ureteric clamping & reimplantation
Pain:
++++ (open surgery= subumbilical midline so T10- L1), multimodal w opioid sparing & regional, rectus sheath catheters for up to 5d, rarely Tx epidural (load once main blood loss risk over), PCA (useful for the visceral pain which can last up to 36hrs postop)
Can also have visceral pain (need up to T4 due to PERITONEAL stimulation)
Combo of pca up to 36hrs & rectus sheath catheters up to 5d promotes earlymobn & return of bowel fn, lack ileus, early d/c
potential for NSAIDs to impair anastamosis so consider carefully after checking renal funciton.
Blood loss: avg 0.5->3L, may be insidious from pelvic venous plexuses, G&S, X-match 4 units, cell salvage (discontinue once bowel opened), (large IVC x2 or one w CVC, art line or oes doppler), have warm line for running blood products (to 37degrees), implement haemostatic resuscitation principles (eg. normothermia, normal acid-base)
consider mild hypotension (titratable rapid acting agents help eg. remifentanil)
Transfusion: there MAY be an ass’n btwn blood transfusion & Ca-related outcomes (blood transfusion has been sig ass’d w lower 5yr recurrence-free survival, Ca-specific survival, overall survival for radical cystectomy), transfusions also incr morbidity & SSI
Metabolic consequences due to ions/electrolyte reabsorption conduit–> acid base & electrolyte disturbances. Consequences of different bowel segments for reservoir:
gastric= metabolic alkalosis with hypokalemia, hypochloraemia, hypergastrinaemia
jejunum= hyperchloremic metabolic acidosis, hyperK, azotemia (high nitrogen)
ileum: hyperchloremic met acidosis, hyperK, azotemia (generally less severe with ileal vs colonic segments). Generally subclinical but may cause muscle weakness, bone demineralisation over longer term. May manage with alkalizing agents blocking Cl- transport (sodium biarb or sodium citrate) or could use chlorpromazine which inhibits Na+, cAMP-mediated Cl- transport)
If pt getting low bicarb, consider the sodibic, Ca & vit D
pts may get B12 deficiency w ileal segment for urinary diversion
colon: hyperchloremic metabolic acidosis, hyperK, azotemia
transverse colon: metabolic acidosis w high Cl, low bicarb, azotemia
Hypokalaemia can occur due to intestinal secretion or renal wasking, hypocalcemia can occur through renal wasting & depletion of body stores, rarely hypoMg++
head down/robotic (eg. well leg, aroid compression stockings if prol head down lithotomy)
infection: ABx prophylaxis, meticulous asepsis
VTE: pharm & non-pharmacological prophylaxis
HDU postop for:
cardioresp monitoring
pain management
electrolyte monitoring
surveillance for bleeding & other complicaitons
TURP
Co-existing disease (eg. CAD, AKI, elderly/frail) common
check electrolytes esp if renal failure & Hb, considering periop risks bleeding & TURP syndrome
can perform under spinal or GA, irrigating fluids risk adverse events & spinal allows early symptom identification (eg. visual disturbances, confusion, headache, anx, seizures, coma, vomit, dyspnoea, arrhytyhmias), hypotension (or TURP syndrome triad of HTN, brady & mental status changes)
If occurs, immediately cease surgery & irrigation. Ax & manage as per ALS, ABC approach 100% O2 & secure airway if compromised GCS or A&B, control seizures, circulatory support (consider inv monitoring if haem unstable), check electrolytes (esp Na) rapidly (along w serum osmolality) & glucose (hyperglycmay risk gblindness). get TEG for coagulopathy. supportive Rx (eg adrenergic drugs, consider diuretics, HTS.
may see raised JVP, pulm oedema, arrhythias, brady or HTN
sluggish pupillary reflex or absent w glycine tox but intact w cerebral oedema
-venous sinus exposure & prostatic capsule injury may–> absorption of irrigating fluids acutely changing IV volume, risks: fluid overload, pulm oedema (esp if Hx CCF), hyper or hypoT, dysrhythmias, hyperchloraemia, hypothermia, coagulopathy
-electrolyte changes: hypo-osmolality, hyponatremia (neurol symptoms if Na+ drops by >=10; earliest signs nausea, more severe= confusion, disorientation, seizures, transient visual abnrormalities). lower volume required for adverse effects in females vs males.
Higher risks with electrolyte-free irrigation (risk if 1.5% glycine (which is 200mOsmol/kg), 3% sorbitol (165mOsmol/kg), by contrast 5% mannitol (275mOsmol/kg) is almost isoosmotic to plasma (280-295mOsmol/kg); isotonic saline (osmol 286) or ringer’s lactate (254mosmol/kg)won’t generate hyponatremia but can only use the electrolyte-free solutions w bipolary diathermy), higher volume (look at fluid deficit; fluid absorption thresholds should be pre-determined in pre-op team brief if nonelectrolyte fluids, eg. 1L temporarily halt TURP 2L terminate procedure). fluid introduced under pressure incr risk, but no diff in fluid absn within range of 60-100cm above OT table. if visceral perforation or prolonged procedure incr risk. intraprostatic injection of vasopressin may be protective vs hyponatremia (reduces absn irrigation fluids)
glycine & sorbitol & some of its metabolites (eg. ammonia) may cause neurotoxicity (eg. encephalopathy, tremor or seizures), glycine may cause visual disturbance).
if asymptommatic & near-normal serum osmolality, no need to correct but closely monitor
if mild w negligible symptoms & vol overload, loop diuretics; if give to those sans vol overload may get hyponatremia
Rx for severe symptomatic hypoNa w low serum osmolality or cerebral oedema= HTS 100mL 3% bolus (51mEq Na, expect serum Na to rise 2-3mEq/L), can do a further 2x 100mL 3% saline 10-minutely if neuro symptoms don’t improve. low risk osmotic demyelination if acute ypoNa but still don’t increase it by 12mEq/L per 24hrs. use slower correction (6mEq/24hrs) if the hypoNa was present for >48hrs.
If mild syptoms w serum Na+ >120, can fluid restrict & loop diuretic
If syptomatic hypoNa w normal osmolality, haemodialysis safest approach (corrects hypoNa, osmotic derangements, vol expansion, removes nonelec soln & toxic metabolytes)
pt should be observed in HDU/ICU while correcting syptomatic hypoNa, hourly Na & K+ & frequent haem & CNS Ax
Other TURP complications:
haemorrhage (may be cncealed)- preop Hb, PBM strategies, transfusion thresholds
myocardial ischaemia
hypothermia
surgical injury (prostitic, bl, urethral perf)
penile erection (for transurethral procedures)
postop:
tyrp syndrome (intra or post)
bl spasm
-Catheter-related bladder discomfort (CRBD) in 50-90%, can–> emergence agitation, parecoxib can help (but care w renal function), dexmedetomidine (continuous infusion) can help, gabapentin also helps (inhibits peripheral sensitisation of afferent c fibre which is ass’d w OAB, urge incont & sensory urgency- 600mg gabapentin), premed w glycopyrrolate also decr postop pain
clot retention
bleeding
VTE
MI
POCD
risk septicaemia may be GN
DIC is a rare complication ass’d with prostate Ca
Positioning risks: lithotomy risk nerve injury, has haemodynamic & resp effects w trendelenberg
TURP ABx= gent, higher dose if preop bacteriuria hasn’t been treated or if evidence UTI. if can’t use gent, cefzol or trimethoprim 300mg po 60mins before procedure.
TURBT
Transurethral resection of bl Ca
endoscopic, Dx & Rx
spinal or GA
spinal needs to cover to T10 (eg. 12mg hyperbaric bupiv & 15mcg fent)- doesn’t prevent obturator reflex so use obturator n block (4X less ob reflex- ipsilat hip addn w obturator n stim). if GA need adequate nmb, enhance relaxation of surrounding skeletal mm enhances surgical conditions.
Transurethral procedures can be interrupted by intraop penile erection, delay procedure & may –> rare complications (eg. strictures, bleeding). dorsal nerve block may reduce sensory input to penis. IV ephedrine, dexmed, glyco, ketamine may Rx. intracavernous (eg phenylephrine) but need close haem monitoring.
Ureteroscopy
to Dx & Rx urinary tract issues eg. stones
Pt may be septic- assess fluid & electrolyte status, renal function
consider spinal or GA, generally GA unless compelling pt factors since GA prohibits pt movemnt & spont br which reduces risk urethral trauma & spinal incr induction time & delays recovery time (if pt well & surgical/pt/facility factors allow could be day case)
Distend renal capsule, ureter & renal collecting system, stimulates nociceptors & produces pain/reflex muscle spasm (flank, groin, scrotal, labial) so adequate analg/anses vital). If using neuraxial, need block up to T6 for renal afferent sensation.
for lasers, most common are KTP:YAG (green light, good coag effect, the Nd:YAG is apssed through KTP crystal which doubles the freq but halves the wavelength) provides almost bloodless course (energy is selectie ly absorbed by Hb), holmium:YAG (not as deep as ND-YAG so less necrosis & thermal damage, rapid coagulation to depth of about 2mm, commonly use for prostate, lithotripsy, ablation urothelial tumours, stricturaes)]
risks to pt staff:
atmospheric contamination from plume (0.31micron easily deposited in alveoli, tearing, eadaches, nausea; limit w high-efficiency masks (N95 filtration of 0.1-0.3micron), smoke evaculator)
risk fires (drapes, ETT (PVC tubes vulnerale to far IR light, sensitive ++ to CO2 laser energy, limit risk w recued FiO2, laser ETT (stainless steel, dual cuff (prox w methylene blue, distal saline, tend to be more rigid/bulky so care to prevent mucosal abrasions), meticulous communiation,, saline nearby, tissue burn)
perforationof vessel/structure (eg. PTx, viscus)/burn (inappropriate energy transfer)
risk venous gas embolism if laparoscopic or hysteroscopic laser surgery- soline collant is the only safe one, if need gas coolant cO2. need vigilance, continuous CO2 monitoring, controlled ventilation)
eye injury (protect pt & staff); corneal injry from CO2, retinal burn from argon, KTP or Nd: YAG, ruby. tape pts eyes closed & cover w opaque saline-soaked knit or metal shield.
OT personnel wear safety gogles for the specific laser wavelength in use (eg. Nd:YAG green-tinted w coating opaque to NIRl argon or kdypton amber-orange lens, KTP:Nd: YAG red filter.
cover all windows to OT & have signs/alarms/locks to prevent people inadvertently entering.
laser monitoring/staff mandatory education.
perc nephrolithotomy
ESWL:
Remote location sometimes, often in theatre needing usual X-ray precautions
prev wet bath (rarely seen)
Energy source (eg. piezoelectric), reflectors to focus shock wave, fluoroscopy. shock wave. Gel pad to ensure unattenuated shock transmission.
Special multifunction tables (usually limited to <150kg) to facilitate concomitant procedures, eg. radiolucent stones may need RGP prior, mayneed to insert stents to assist drainage.
Needs immobility & minimal ventilatory excursion for targeting, stone in focal range.
Tilt may be required for some stone locations
CI in preg, coagulopathy, abdo pacemakers
difficult obese pts (focussing stone within range.
ANS hyperreflexia pts.
risky proximate to AAA.
pacemaker tech discussion/strategy. pacemakers sensitive to ESWL interference. Turn off AICDs (pads on), shield posterior thorax w styrofoam. no dressings on skin (esp epidural)
need anaesthesia to T6 intra-op, minimal pain postop.incr voltage, pressure @ skin, upper calyx more painful.
Can do GA, sedation, regional
*shockwave interferes w monitors.
Risk contusion or haemoptysis.
risk shock waves damaging other areas ieg. flank ecchynmosis, haematuria, punctate haemorrhages in bowel.
PCNL: high rate of stone-free result, improves renal funciton more than ESWL. but higher morbidity & complications.
for Rx renal stone >1.5cm-2cm or staghorn calculi or lower pole stone or refratory (to ESWL) upper tract calculi
-Initial lithotomy for ureteric stent. then moved PRONE under GA or spinal
-adv. small incision (perc access to collecting system, fluoroscopy guided), use ultrasonic or pneumatic or laser lithotripters. irrigation to remove fragments. postop nephrostomy drain.
kidneys retroperitoneal, R) adj to R12, liver, duodenum & hepatic flexure. L) related to r 11/12, stomach. Sup pole in contact w diaphragm.
-complications=
pleural injury (up to 3%), ptx or hemothorax. higher risk w more superior punctures, fluroscopic montioring during procedure may allow early detection of PTx or at least Postop CXR in pacu. monitor SpO2 EtCO2. minimise pleural injury w communicaiton re: timing of renal tract dilation& respiration pt in prone/lateral oblique position.
small bowel injury, renal perforation, colon injury, hepatic injury, splenic injury (these complications may–> sepsis or peritonitis)
-fluid absorption
-BLEEDING from renal capsule or parenchyma (1% require angioembolisation due to major bleeding) –> preop optimise coagulopathy
-pain
-fever
-UTI
-septicaemia
-risk acute anaemia w dilution or bleeding, fluid absorption w high pressure irrigation & venous injury.
-care w hypothermia w large vol irrigation fluid. warm IV & irrigation fluids (shiver, delayed drug Cl, VC)
urine cultures pre-op.
-benefit GA= secure airway, less risk pleural injury by controlling TV BUT risk pressure injury (eyes, ears, nose, bony structures)
-benefit spinal= better analgesia & shorter recovery (lower OT time, less analgesic requirements, shorter LoS) but may be less comfortable for pt to be awake if prolonged & may agg unstable haemodynamics
Pain control & recovery:
-Urologic surgeries ass’d w mild-moderate pain, adequate analgesia vital in improving quality of recovery
-TAP block: good analgesia & reduced opioid consumption & shortened LoS in pts undergoing minimally invasive surgery
-LA delivered into the layer btwn IO & TA, blocking sensory pathways of intercostal nerves T7-11, subcostal nerve T12 & ilioinguinal & iliohypogastric nerves L1 which innervate anterolateral abdominal wall
-TAP block vs epidural: no sig difference in pain score @ postop D1 btwn the groups but hypoT & LoS sig shorter in TAP block
ERAS important for urologic surgery because:
SURGICAL FACTORS:
-long operative time
-incr risk bleeding
-higher complication rates
PT FACTORS:
-usually elderly w comorbidities, anaemia or malnutrition
Gynaecological malignancy:
PATIENT & pre-op (risk identification & stratification, optimisation in liaison w multi D (eg. oncology, haematology, allied health)
time critical so limited time to optimise but any pulmonary risk minimisation (smoking cessation, bronchodilators), CV risk (HTN control, optimising medical Mx), haematological (eg. anaemia), medication advice
ERAS principles not widely defined in gynae-onc but can be used for staging lap, hypsterectomy or 2nd=look laparoscopy after chemo- less infections exposure, rapid return to community, cost saving.
pt prep for major surgery eg. preop counselilng re: factors such as stoma, discussion re: plan incl HDU, discuss goals of care.
functional status/consideration of fitness for major OT
preop dyspnoea may be compounded by ascites (in 90% of pts w stage III=IV ovarian Ca)
surgery contraindicated if rapidly accumulating ascites, high bowel obstruction or multi-level bowel obstruction.
consider comorbidities wrt surgical approach, eg. if severe IHD, ESRF, advanced valvular lesions, sig lung disease consider open vs lap.
consider indication if hysterectomy eg. menorrhagia
4M’s (gynaecological malignancy may present late for Rx & have large tumour before investigation.
metabolic effects (eg. cachexia, paraneoplastic syndromes eg. for ovarianP cerebellar degen, nephritic syncrome, retinopathy, cauda equina; uterine: hypercalcemia, retinopathy, peripheral neuropathy, encephalitis, myelitis, dermatomyositis)
malnutrition (may have had anorexia/ N&V eg. if Ca has omental spread)
mass effects
mets (Cervical Ca risk facors aside from HPV incl smoking, diet, ocp, immunosuppressiontypically squamous, spreads to myometrium, paracervical lymph or via obturator fascia to other pelvic organs (bl, rectum), haematogenous spread to lung, liver, bone. early invasive disease simple hysterectomy, later stages radical (uterus, some of vagina, ligaments, pelvic nodes), often preserve ovaries/vagina if reproductive age.
uterine (endometrial) risk= hormonal, high BMI, DM, low physical activity, smoking, Dx w D&C. spread is local invasion, tubal (peritoneal mets, lymph, haematogenous to lung/liver/brain/bone. Rx w TAH & BSO, full pelvic lymphadenectomy.
Ovarian: often later present, poorest survival, spreads to pelvic organs w no boundaries (peritoneal carcinomatosis), complete tumor removal ass’d w improved survival so Rx= highly invasive, complex surgery. my get lymphatic spread above diapharagm, haematogenous to parenchymal mung mets, skin nodules, pericardial effusion, CNS, bone. risk facotrs for distant= malignant ascites, carcinomatosis, mets in abdo. ovarian & pelvic Ca can be secondaries from bowel or breast. risks= age, FHx, nullip, PCOS, PID, fats in diet.
vaginal/vulval: mostly vaginal Ca is secondaries from other pelvic Ca (esp uterus, ovaries, rectum. spread to pelvis or via lymph to lungs, liver, bone. typically Mx w partial vaginectomy & lymphadenectomy then radiotherapy.
vulval Ca also uncommon, spreads to vagina, urethra, anal canal, lymphatic spread to inguinal, pelvic & femoral nodes, distant to bone, liver, lungs. Block dissection. risks incl age, smoking, hpv.
pain assessment (risk facotrs for chronic pain incl prev chemo, large incision & resection)
for laparotomy interval cytoreduction for high grade adenocarcinoma: pt may have omentoperitoneal disease & ascites (risk factors for distant metastatic spread)
meds; pts may have had neoadj chemo before cytoreductive surgery & presen for interval debulking. platinum-based drugs eg. cisplatin used for ovarian Ca, dyspnoea/cough/hoarseness, black stools or haematuria, altered sensations, anaemia, bleeding/bruising, infection risk.
Ix: FBC, clotting, urea & electrolytes, LFTs, G&S or Xmatch, CXR, ecg.
echo useful if Hx IHD, valve disease, unexplained dyspnoea, anticipated haemodynamic swings
preop MRI of abdo & pelvis helps predic EBL, need for ureteric stents, perc nephrostomies or bowel resection.
PROCEDURE:
laparoscopic, open, abdo or vaginal for hysterectomy
laparotomies for gynae Ca (eg ovarian) may be extensive (limiting residual disease confers survival benefit so maximal surg debulking may involve radical oophorectomy +/- recto-sigmoid colectomy, bowel resection (ie. may have postop stoma), splenectomy, diaphragmatic perinectomy, omentectomy & liver resection, w abdo incision from xiphoid to pubis. If liver mobilisation, risk postop pleural effusion so may do chest drain. if invasion near hepatic vessels, may clamp suprahepatic & infra VC, hepatic vein & hilum to reduce bleeding.
Pelvic exenteration= radical surgery for severe pain releif life extension or even cure for pelvic Ca. extreme enbloc resection of all pelvic organs w urinary diversein, end-sigmoid colostomy, vaginal recon. generally performed after radiotherapy. candidtae selection crucial.
prolonged, potentially difficult surgical access (eg. if prev abdo procedures, ascites), may require input from other surgeons if proximity to other structures (eg. renal, colorectal)
procedure may involve surgical staging
Position/pressure areas (open ULs out, often laparoscopic arms wraped by side limits access.
consideration of prolonged steep head own & risk airway oedema.
at risk pts 1st on list.
IVCs visible & have backup.
BIS to limit deep anaesthesia (POCD, slow wakening)
normothermia (temp probe IDC, warm)
ETT cuffed w LPV
fluid Mx erring to restrictive but ensure euvolaemia (monitor w dynamic eg PPV, static eg. lactate, UO, ScvO2)
Intra-op risk mitigation & postop complication surveillance:
POTENTIAL COMPLICATIONS:
Haemodynamic esp w laparoscopic eg. vagal response w pneumoperitoneum/ peritoneal manip), consider volume status pre-induction (may have had enemas eg. microlax or if bowel involvement w ovarian Ca osmotic sodium phsophate (fleet) laxatives may be given.
pts w preop N&V may benefit from IVT during preop fast.
potential for significant fluid shifts. Goal-directed.
Bleeding:
art line, 2x 16gabue (if not pross eg. prev chemo or sig CV comorbidities, CVP)
large-bore warm line for drugs closest to door, separate line for drugs/infusion pumps & art line on other side.
PBM principles
pre-op assess for symptoms of anaemia, signs & symptoms of bleeding, establish if insufficient Hb production (eg. Fe def) or losses (eg. antiplatelets)
optimise red cell mass w haematinics (eg. Fe infusion if OT<2/52 away, PO w re-Ax if 4-6wks; Fe defic absolute if ferritin <30microg/L, 30-100 w raised CRP suggestive, look at Tsat)
obtain G&H & screen for antibodies, consider cell saver if significant vessel proximity
predetermine transfusion threshold based on comorbidities
limit blood loss: medication advice re: witholding anticoagulants/antiplatelets
normothermia pre & intra warm, & intraop limit crystalloid, avoid acidaemia
meticulous surgical technique
consider TxA
optimise physiological tolerance of anaemia: optimise preop CP function, adequate analg/anaes to limit SNS & O2 demand
Postop pain:
multimodal opioid sparing (oncoanaes, chronic pain risk, ERAS principles, limit adverse effects of opioids eg. ileus, ponv)
parecox, lg dose dex, IV lig infusion 1.5mg/kg IBW dose then 1mg/kg/hr infusion
Mg++ ketamine, intraperiotneal ropiv, bup
for phannenstiel or vertical infraumibilical incision without sig risk factors for postop pain, US guided TAP @ end of procedure.
pts with risk factors for sign postop pain (prev chemo, biosocial factors, extensive surgery, nerve nvolvement) gabapentin 600mg 1hr preop but avoid other intraop sedatives. halve dose if renal dysfunction.
intra op ketamine infusion if Hx chronic pain, outpatinet opioids or illicit drug use.
low thoracic epidural if upper abdo resections (will need postop HDU) or if high risk of postop pain. suggested by BJA but APMSE: epidural may incr LoS, risk incr complications, ITM may provide acceptal alangesia & lower opioid requirments. minimal benefit & higher risk suggested.
if low risk chronic pan, opioids & wound infiltration.
tap blocks (subcostal for supraumblical), PCA for visceral pain up to 36hrs
chronic pain after abdo hysterectomy up to 30%, risk factors don’t include surgical approach, risks incl poorly controlled pre- or postop pain & anx.
APMSE: spinal vs GA reduces risk of chronic pain (after hysterectomy or CS)
gabapentin pre only or pre& postop both reduce 24hr morphine consumption (more powerful effect w pre-op only)
neuraxial opioids may be used for hysterectomy, may have a celinig effect for anagesia risk-benefit balance up to 150microg IT & up to 3.75mg via epidural route. ITM added to bupiv for postop analgesia after abdo hysterectomy reduces postop oioids & no additional enefit if larger dose 300mcg vs 200mcg.
IV Mg++ may prolong duration of sensory block for abdo hyster & reduce postop pain the first 4hrs postop.
ketamine or dexmed added to LIA comparable analgesia & both superior to bupiv alone.
ABDO HYSTERECTOMY: TAP block provided best pain relief & lowest opioid rescue vs epidural analgesia or parenteral.
subcostal tap if supraumbilical incision for improved access vs extensive resection.
radical vulvectomies not extending above inguinal ligament= only procedures for single-shot spinal. for all other gynae onc, GA needed.
abdo pain in peritoneal carcinomatosis may be refractory to opoioids- glucocorticoids exert opioid sparing effect, high dose eg. 15mg preop or 10mg post reduce opioid consumption in 24hrs after physteretomy.
PONV: aggressive multimodal approach. limit baseline risk (regional, avoid VA & N2O), additional multimodal Rx. aprepitant= lincensed for chemo-induced PONV, oral dose pre-op PONV prevention.
delirium/POCD: esp elderly, those w hypoalb, ass’d comorbidities.
Infection: Antibiotics:
vaginal: cefazolin PLUS metronidazole (15-30mins pre-incision)
abod: cefazoli
if immed hypersens to cefzol, clinda 600mg IV over @ least 20mins, 15-30mins pre-incision
pulmonary: vent issues if steep head down lithotomy, postop pain (esp radical procedures w upper abdo) & atelectasis.
VTE risk high++ (procoagulant state w TF release from tumour cells, pelvic tumours may compress maj vessels–> stasis, immobilisation). care ++ w UL CVC (UL thrombosis risk up to 66%. chemo endothelial damage & reduced prot C&S, inflamm cytokines incr risk. fatal embolism in 1%)
pharm & non-pharm. may have therapeutic anticoag if recurrent thrombotic episodes; haematology advice re: plan for recommencement of therapeutic anticoag, implications for analgesia.
staff risks (higher rates obesity in gynae cancers). hover matts, slide sheets, trenguard for lityotomy head down.
Postop: complication surveillance
surgical: blood vessel, ureter injury.
setpic complications, SBO w pelvic exenteration.
for major gynae, HDU for bleeding, pain management, PONV management, haemodynamic monitoring
decision re: extubation (pt, surg, anaes)
Emergency laparotomy
Emergency procedure, little time to identify & stratify risks & optimise however essential to:
-consider & treat sepsis, goals as per 2021 surviving sepsis:
- early ABx within 1hr reduce mortality in septic shock
- preop resus fluids in boluses up to 30mL/kg, aim MAP >65mmHg
- frequent re-Ax
- resus should occur concurrently with timely OT access, must not delay access to OT source control (aim= definitive surgery within 2hrs (the most life-threatening) to 6hrs of decision)
- NAdr first line vasopressor for fluid-resistant hypotension
Pt pathopysiology in sepsis: vasoplegia (venous & arterial), incr tissue oedema (endothelial glycocalyx disruption), ventricular dysfunction.
CO monitoring & early use of vasopressors valuable- Ax of fluid balance is challenging (significant fluid shifts & losses) & excess fluids may have detrimental effects.
-assess & manage the impact of any bowel obstruction (eg. hypovolaemia, electrolyte disturbances, AKI, atelectasis)
-identify significant comorbidities & account for these in anaesthetic management
-routine bloods: arterial or venous gas, lactate, pregnancy test
-Ix: ecg, CXR, usually CT
Priorities of intra-op management (risk mitigation):
- rapidly secure airway, minimising risks of pulmonary aspiration
- haemodynamic stability during RSI & periop period
- optimal fluid type & volume
- limit hypothermia & its sequelae
- lung protective ventilation
- analgesia
- postoperative complication surveillance
- NAP4, most common “anaesthetic” cause of death= pulm aspiration, incidences of aspiration 1:400,000 elective, 1:900 for emergency
priority= suction NGT, rapid induction of anaesthesia & NMB for optimal intubation conditions & haem stability - rapid-acting opioid (dose chosen to be rapid but wary of pts sympathetic reserve), ketamine 1-2mg/kg, vasopressor anticipatory, roc 1.2mg/kg
- IVT guided by haemodynamic features (HR, MPA), markers of organ perfusion (lactate, BE), dynamic (PPV, SLR, echo). site art line pre-induction. CVC if pt requires vasopressors. IDC for UO monitoring. Balanced crystalloid initially 1.5:1, colloid 1:1 replacement until transfusion threshold reached.
GDFT reduces complications of surgery & LoS but no effect on mortality cf conventional fluid admin. egs of GDF pulse contour analysis, oes doppler. fluid-resistant hypoT NAdr 1st-line vasopressor. GDFT intra- and ostop. - monitor temp, fluid & surface air warmers (limits risk coagulopathy, wound infection)
- to limit volutrauma & barotrauma, low TV sans high PEEP good starting point for pts sans ARDS, optimisation of PEEP & use lung recruitment as indicated. ALI= most common cause of postop resp failure. The abdo pathology may influence ability to ventilate the pt, permissive hypercapnia may not be appropriate if pre-existing metabolic acidosis.
- inadequate analgesia contributes to postop complications & mortality. somatic pain (incision) visceral pain (peritoneum); visceral resolves more rapidly (eg. 36hrs) than somatic. goal= manage incision pain so can mobilise & limit pulm complications, best to limit opioids for this compoennt (intra or postop); limit POCD, resp depression, GI dysfunction. central neuraxial (ITM), TPA, rectus sheath (care w hypoT w neuraxial, CI if sepsis, hypovol, coagulopathy). alternative= IV lignocaine. adjuncts: ketamine, Mg++, evidence mainly from elective abdo surgery. lignocaine infusion improve postop GI motility & reduce opioid requirements. ketamine reduce opioid requirecment & reduce risk chronic postop pain. Mg++ reduces opoioids, improves analgesia & reduces hyperalgesia w remi but risks hypoT & prol NMB. opioid for visceral pain- rapid-acting titratable for limited period. parcetamol. NSAIDs often CI due to risk renal failure.
- Pts w mortality risk >10% to ICU (there’s a risk calculater for the NELA for this). others suggest LL pts w emergency laparotomy should go to ICU. decisions re: tracheal extubation incl pt (acid:base, O2 & vasopressor reqt, temp), OT & anaes factors. further resus may be required postop. if extubate, risk of aspiration considered (aspirate NGT & suction pharynx, only extubate fully reversed, upright, awake. surveillance for pulm complications, myocardial ischaemia, thrombotembolic events. consider glucose control & nutritional status (hypercatabolic state from sepsis 7 surgical stress response). may need dietetics input or parenteral neutrition (risk malnutriotn, sarcopenia, weakness). VTE risk; periop prophylaxis. Recommendations after UK national laparotomy audit: formal risk-Ax, consultant-led Ix & surgery for higher risk pts, utilise critical care postpop, involvement of geriatricians if age 70+.
high mortality w emergency laparotomy, bundle of care pathways implemented in some hospitals aiming to risk stratify, promote seniour input, rpaid assessment & care, access to critical care & reduce m&m. (early Ax & resus, early ABx, prompt Dx & early OT (eg in scanner w rapid verbal report, emergency laparotomy code to next slot), GDFT, postop ICU with ongoing GDFT.
ERCP
Gold standard for imaging biliary tree but since less invasive Dx procedures (MRCP & EUS), ERCP now largely for therapeutic vs diagnostic indications.
Offers various interventions for pts deemed too high risk for OT.
Combined endoscopy & fluoroscopy, Dx & therapeutic for pancreatobiliary conditions.
Endoscope to D2, AV opening found, biliary & pancreatic ducts cannulated, contrast is injected & visualised under XR, stone retrieval, lithotripsy, stent, balloon dilatation & spnincterotomy can be done.
Indications:
choledocholithiasis in pts unfit for OT or who’ve had cholecystectomy
pancreatitis or cholangitis needing emerg drain
inoperable malig & OJ
SOO dysfunction & biliary manometry
postop complications eg. bile leaks or biliary strictures
can do in conjunction w EUS & chalongioscopy to aid ablation, tissue sampling & direct visualisation of biliopancreatic ducts.
REMOTE ANAESTHESIA:
-cramped space (staff, stack, XR, anaes equip, emerg equip) so limited pt access, non-tilting table, sometimes PRONE
-radiation hazards
-unfamiliarity of staff & unfamiliar equip w anaes reqt’emerg procedures
Monitoring pulseox, BP, ecg, capnograph
dedicated recovery area
PRE-OP risk id, strat, opt w multi D:
Most ASA >=3 & multicomorbid incl IHD, metastatic, DM, COPD, renal, CCF, AF
inadequate sedation risks poor pt tolerance & failure rates, generally do under dep sedation w propofol
sedation-related AEs incr w duration of procedure: loss of airway requiring maneouvers (risk obesity, COPD, OSA, use of bolus vs TCI, procedure >1hr), hypoxia (risks COPD, OSA, severe acute illness, bolus vs TCI, procedure >1hr), apriation (risks ileus, ascites, ETOH excess, unprotected airway & proc >1hr)
hypotension (risks CVD, severe illness, elderly, GA, bolus vs TCI, prolonged proc), arrhythmia (CVD, severe illness, SNS, anticholinergic), conversion to GA (OSA, COPD, obese, high sedn, long proc). proc-related: pancreatitis (Hx acute banc, SOO dysfn, younger, female, normal bilirubin serum, difficult cannulation, pancreatic duct diln/contrast, biliary sphincterotomy), haemorrhage (coag, active cholangitis, anticoag within 3 days, operator inexperience), pancreatobil or duodenal perf (SOO dysnfn, PSC, chonangiocardc, elderly, anatom issues, pt movement during procedure, diff cannulation, biliary sphincterotomy or stricture dilation), post-ERCP cholantigis (risks bacteremia, perc endoscopic procedrue, malign strict stent, incomp biliary drain or stone clearance, forgetting proph ABx in pst w bilary obstn), cholecystitis(cholelithiasis, stent blocking CD), VAE (duct dilation, stent placement, direct cholangioscopy)
GA for pts w high risk sedation-related AEs, complex & painful procedures, conversion to GA. hypotension main AE related to GA, may contributed to AKI, mort, LoS.
Prone positioning allows easier cannulation of the ampulla of vater, more comfy for pt & easier for anaes but procedurailit afaces away from pt & it’s tech challenging. supine or lat decubitis better if obese, ascites, critically ill.
may be painful, use paracetamo, NSAIDs, opioids (not CI despite risk SOO contn)
antispasmodics glucagon or hscine may be given to reduce peristalsis; lattter antimusc & anticholin & care w cardiac diseae & glaucoma.
