AS - Surgery Pre-Op Assessment Flashcards
Pre-op Checks for surgery?
Operative fitness: cardiorespiratory comorbidities
Pills
Consent
History: MI, Asthma, HTN, Jaundice. Complications of anaesthesia: DVT, Anaphylaxis.
Ease of intubation: neck arthritis, dentures, loose teeth.
Clexane: DVT prophylaxis (heparin)
Site: correct and marked.
Surgical evaluation of the abdomen
Lie patient flat with arms down. Patient may be rolled right or left. Ask patient to cough during inspection to reveal hernias. Stand patient up to examine groin only if necessary. Inspect Palpate Percuss Auscultate
Background paperwork for patient surgery?
- Medical notes
- Check blood results - Clotting for anticoagulated patients
- K+ for patients with renal failure
Ca2+ for parathryroidectomy patients. - Consent forms
- Drug chart
Patient prep?
- Blood products
- Bowel prep
- Anaesthetic premed
Can patient have AED when they has surgery?
Give as usual
Post-op may need IV or NGT
Can patient have OCP when theh has surgery?
No. Stop 4 weeks before major/leg surgery.
Restart 2 weeks post-op if mobile.
Can a patient have B-Blocker when they have surgery?
Continue as normal
What pre-op investigations are required?
Routine: FBC, U+E, G+S, clotting, glucose
Specifics:
- LFTs: liver, EToH, Jaundice
- TFT: thyroid disease
- Se electrophoresis: Africa, West Indies, Med.
ECG used for >65
renal disease may need FBC + EG.
CXR NOT ROUTINELY USED.
Cross-match
- Gastrectomy: 4U
- AAA: 6U
Prophylactic medications for pre-op - Clean bowel surgery?
Antiobiotic - Check hospital guidelines.
e. g ‘Clean’ bowel surgery like appendicitis, colonic resection = - Cefuroxime 1.5g IV + metronidazole 500mg IV
- IV amoxicillin 500mg IV + metronidazole 500mg IV.
Prophylactic medications for pre-op - Clean hepatobiliary surgery ERCP, open biliary surgery?
Gentamicin 120mg IV + amoxicillin 500mg IV + metronidazole 500mg
Prophylactic medications for pre-op - Clean gynaecological surgery?
Metronidazole 500mg IV or 1g PR
Prophylactic medications for pre-op - Clean Elective orthopaedic surgery
Flucloxacillin 1g IV
Prophylactic medications for pre-op - Clean vascular surgery
Flucloxacillin 500mg IV + gentamicin 120mg IV + amoxicillin 500mg IV.
Thromboprophylaxis pre-op?
- TED stockings - Reduce stasis infrapopliteal veins.
- Heparin. Activates antithrombin III. Prophylaxis: 5000U SC od.
Treatment: IV 2000U Loading, 2000U/h. Check APTT 6hr after starting and 6-12 hr thereafter. Maintain APTT 50-70 - LMWH. Activates antithrombin III. SC injection.
= Prophylaxis: 20-40mg SC Clexane od. - Treatment: 2mg/kg SC in two divided doses.
Clotting cascade drugs?
- Heparin
- LMWH: Clexane - 20-40mg prophylaxis. Treatment = 2mg/kg SC in two divided doses.
Antiplatelet drugs - not used as VTE prophylaxis .
Aspirin (300mg PO OD)
Dipyridamole (75mg PO QDS)
Clopidogrel (75mg PO OD)
Risk stratification for DVT Prophylaxis.
Low-risk: Early mobilisation
Medium risk: Early mobilisation + TEDS + 20mg enoxaparin
High: Early mob + TEDS + 40mg enoxaparin + intermittent compression boots perioperatively.
Prophylaxis started @ 1800 post-op .
May continue medical prophylaxis at home (up to 1mo)
NBM surgery?
> 2hr for clear fluids. Black coffee includes this.
> 6hrs for solids.
What is the required bowel prep?
Needed in left-sided operations:
- Picolax: picosulphate and Mg Citrate
Klean-Prep: Macrogel
Not usually needed in right-sided procedures.
Necessity is controversial as benefits of minimising post-op infection might not outweigh risk.
- Liquid bowel content spilled during surgery
- Electrolyte disturbace
- Dehydration
- Increased rate of post-op anastomotic leak
Given day before examination.
Required not to eat 24hr before examination.
- Day before procedure and day of procedure.
ASA Grades?
- Normally healthy
- Mild systemic disease - current smoker, obesity, well controlled diabetes.
- Severe systemic disease that limits activity (1 or more systemic diseases) = Poorly controlled diabetes, HTN, COPD, ESRD.
- Systemic disease which is a constant threat to life. MI recent, CVS accidents, DIC, ARD, ESRD not undering dialysis.
- Moribund: not expected to survive 24hr even with op.
Specific pre-operative complications? Diabetes
Increased risk of post-operative complications
- Surgery –> stress hormone –> Antagonise insulin
- Pts are NBM
- Increased risk of infection
- IHD and PVD
Specific pre-operative management Diabetes
- Dipstick: proteinuria
- Venous glucose
- U+E= K+.
What are the practical points of dealing with insulin dependent DM?
- Put the patient first in the list and inform the surgeon and anaesthetist,
- Some centres prefer to use GKI infusions.
- Sliding scales may not be necessary for minor ops. If in doubt, liase with diabetes specialist nurse.
What is the management of insulin with IDDM patients?
- ± stop long-acting insulin the night before.
- Omit AM insulin if surgery is in the morning.
- Start a sliding scale 5% Dex with 20mmol KCL 125ml/hr. Infusion pump with 50u actrapid. Check CPG hrly and adjust insulin rate.
- Check glucose hrly: aim for 7-11.
- Post-op: Continue sliding-scale until tolerating food. Switch to SC regimen around a meal.
Management pre-op of non-insulin dependent DM?
- If glucose control poor (fasting >10mM): treat as IDDM
- Omit oral hypoglycaemics on AM of surgery
- Eating post-op: resume oral hypoglycaemics with meal
- No eating post-op: Check fasting glucose on AM of surgery. Start insulin Sliding scale.
Consult specialist team re restarting PO Rx.
Management pre-op NIDDM diet controlled?
Usually no problem
Pt may be briefly insulin-dependent post-op.
- Monitor CPG
Minor surgery re diabetic pre-op?
Oral controlled: Give normal regimen
Insulin controlled: Omit pre-operative insulin day of surgery; monitor blood sugar every 4h; restart normal insulin once oral diet is established.
Avoid cannulating foot.
Major surgery re diabetic pre-op
Oral controlled: Omit long-acting hypoglycaemics preoperatively. Monitor BS Every 4hr. If BS exceeds 15mmol/L, start IV insulin regimen.
Insulin-controlled: Commence sliding scale IV preoperatively once NBM and continue until normal diet resumed. Check BS 4hrly. Restart normal insulin regimen (initially half dose) once oral diet is established.
Emergency surgery re diabetic pre-op
Check for existing ketoacidosis.
IF present use medical treatment algorithm to control BS and postpone surgery until BS <20 unless condition is life-threatening.
Use iV insulin sliding scale for all patients to optimise BS control. A typical IV sliding scale (Actrapid with 5% dextrose) is:
- BS <4mmol/L infusion 0.5u/h + consider medical review
- BS 4-15mmol/L, infusion 2.0U/h
- BS 15-20mmol/L, infusion 4.0U/h
BS >20, infusion 4 + cnsult diabetes team + consider DKA treatment
Risk of patients on steroids for surgery?
Poor wound healing
Infection
Adrenal crisis
Management of a patient who uses steroids for surgery
Increase steroid to cope with stress
Consider cover if high-dose steroids within last year
Major surgery:
Hydrocortisone 50-100mg IV with pre-med then 6-8hrly for 3ds
Minor: as for major but hydrocortisone only for 24hr
Management of patients with jaundice for surgery?
Best avoided
Use ERCP instead
Risk of operating on patients with Jaundice
- Patients with obstruction have increased risk of post-op renal failure so need to maintain good UO.
- Coagulopathy
- Increased risk of infection: may develop cholangitis
Pre-op management of jaundice?
- Avoid morphine in pre-med
- Check clotting and consider pre-op vitamin K
- Give 1L NS pre-op (unless CCF) –> moderate diuresis
- Urinary catheter to monitor UPO
- Abx prophylaxis e.g cef and met
Intra-op management of jaundice
Hrly UO monitoring
NS titrated to output
Post-op
Intensive monitoring of fluid status
Consider CVP + frusemide if poor output despite NS
Anticoagulated patients management surgery?
- Balance risk of haemorrhage with risk of thrombosis
- Consult surgeon, anaesthetist and haematologist
- Very minor surgery can be undertaken without stopping warfarin if INR <3.5
- Avoid epidural, spinal and regional blocks if anticoagu
- In general, continue aspirin/clopidogrel unless risk of bleeding is high - then stop 7d before surgery.
Low thromboembolic risk: e.g AF - Anticoagulation
- Stop warfarin 5d pre-op: need INR <1.5
- Restart next day
High thromboembolic risk: valves, recurrent VTE. - Anticoagulation
Must bridge with LMWH
- Stop warfarin 5d pre-op and start LMWH
- Stop LMWH 12-18hr pre-op
Use mechanical prophylaxis
- Restart LMWH 6h post-op
- Restart warfarin next day
- Stop LMWH when INR >2
LMWH = patients with normal renal function. Given as one daily subcut. Binds antithrombin.
Unfractionated - binds anthrombin III with thrombin + factor Xa. Activity measured using APTT. Reversed with protamine.
Dabigatran
- Orally administered direct thrombin inhibitor.
- No monitoring.
Emergency surgery coagulation
- Discontinue warfarin
- Vitamin K 5mg slow IV
- Request FFP or PCC to cover surgery
Risk of patients with COPD and smoking for surgery?
- Basal atelectasis
- Aspirations
- Chest infection
Smoking - reduced immune funciton. Increases platelet aggregation. Reduced oxygen-carrying capacity of blood per unit volume. Increased upper aerodigestive mucosal secretions.
Reduced mucociliary escalator function.
Pre-op management of patients with COPD
- CXR
- PFTs
- Physio for breathing exercises
- Quit smoking (4 weeks prior to surgery)
Mitigating the effects of smoking in post-operative period?
Active + recently stopped smokers should receive extra attention to preventing risk
- Ensure patient remain well hydrated until oral intake is restored.
- Use preoperative chest physio + education on breathing and coughing techniques.
- Mobilise as soon as possible post-operatively.
- Consider use of epidural anaesthesia to improve compliance with post-operative physio.
- Use preoperative + post-operatie saline nebs 5ml qds
Principles and practical conduct of anaesthesia?
Aim: Hypnosis, analgesia, muscle relaxation
Induction: e.g IV propofol
Muscle relaxation
- Depolarising: suxamethonium
- Non-depolarising: vecuronium, atracurium (reversed with sugammadex)
Airway control: ET tube, LMA
Maintenance - Usually volatile agent added to N2O/O2 mix (halothane, enflurane)
- End of Anaesthesia
Change inspired gas to 100% O2
Reverse paralysis: neostigmine + atropine (prevent muscarinic side effects).
What drug is used for anaesthesia induction?
Ketamine
- Makes you sick
- Little myocardial depression - for those who are haemodynamically unstable.
What drugs are used for muscle relaxation?
- Depolarising: suxamethonium
- Non-depolarising: vecuronium, atracurium
What drug is used for maintenance of anaesthesia?
Volatile agents such as halothane or enflurane.
IV propofol
Pain on IV injection
Proven anti emetic properties
Maintains sedation.
The 7 As of pre-medication of anaesthesia?
Anxiolytics and Amnesia: e.g temazepam
Analgesia: e.g opioids, paracetamol, NSAIDs
Anti-emetics: e.g ondansetron 4mg/metoclop 10mg
Antacids: e.g lansoprazole
Anti-sialogue e.g glycopyrolate (decreased secretions)
Antibiotics
What is regional anaesthesia and where is it used?
- May be used for minor procedures or if unsuitable for GA
- Nerve or spinal blocks. CI: local infection, clotting abnormalities
= Use long-acting agents: e.g bupivacaine
Complications of Anaesthesia?
Propofol Induction
- Cardioresp depression
- Suxamethonium apnoea. AD mutation - lack of specific acetylcholinesterase in plasma.
Intubation
- Oropharyngeal injury with laryngoscope
- Oesophageal intubation
Loss of pain sensation
- Urinary retention
- Pressure necrosis
- Nerve palsies
Loss of muscle power
- Corneal abrasion
- No cough –> atelectasis + pneumonia
Malignant hyperpyrexia
- Rare complications due to halothane or suxamethonium
- AD inheritance
- Rapid rise in temperature + masseter spasm
- Tachycardia, muscle rigidity, rhabdomyolysis, hyperthermia, arrhythmia.
- Rx: Dantrolene + cooling
Anaphylaxis
- Rare
- Possible triggers = antibiotics, colloid, NM blockers: e.g vecuronium
Necessity of analgesia?
Pain = autonomic activation --> Arteriolar constriction --> decreased wound perfusion --> Impaired wound healing Pain = decreased mobolisation --> Increased VTE risk and decreased function Pain = Decreased resp excursion and decreased cough --> Atelectasis and pneumonia
General guidance for pain management?
- Give regular doses at fixed intervals
- Consider best route: oral when possible
- PCA should be considered: morphine, fentanyl
- Follow stepwise approach
- Liaise with Acute Pain Service
Pre-op pain management?
Epidural anaesthesia. e.g bupivacaine
End-op pain management
Infiltrate wound edge with LA
Infiltrate major regional nerves with LA
Post-Op stepwise pain management?
Stepwise approach:
Non-opioid ± adjuvant
- Paracetamol
- NSAIDS - ibuprofen 400mg/6h PO max. diclofenac 50mg PO/75mg IM.
Weak opioid + non-opioid±adjuvants
- Codeine
- Dihydrocodeine
- Tramadol
Strong opioid + non-opioid ± adjuvants
- Morphine: 5-10mg/2h max
- Oxycodone
- Fentanyl
Indications for spinal or epidural anaesthesia?
Decreased SE as drugs more localised 1st line for major bowel resection Caution - Respiratory depression - Neurogenic shock --> Decreased BP
Enhanced recovery after surgery?
- ERAS commonly employed in colorectal and orthopaedic surgery
Aims of ERAS?
- Optimise pre-op prep for surgery
- Avoid iatrogenic problems (ileus)
- Minimise adverse physiological/immunological responses to surgery such as:
1) increased cortisol and decreased insulin (absolute or relative)
2) hypercoagulability
3) immunosuppression - Increased speed of recovery and return to function
- Recognise abnormal recovery and allow early intervention
Pre-op ERAS?
Aggressive physiological optimisation
- Hydration
- BP (increased/decrease)
- Anaemia
- DM
- Co-morbidities
Smoking cessation: >4 weeks before surgery
Admission on day of surgery, avoid prolonged fast
Carb loading prior to surgery: e.g carb drink
Fully informed patient, encouraged to participate in recovery
Intra-operative: decrease physical stress
- Short-acting anaesthetic agents
- Epidural use
- Minimally invasive techniques
- Avoid drains and NGTs where possible
Post-op: early return to function and mobilisation
- Aggressive management of pain and nausea
- Early mobilisations and physiotherapy
- Early resumption of oral intake (inc carb drinks)
- Early discontinuation of IV fluids
- Remove drains and urinary catheters ASAP.
General complications of surgery: Immediate (<24hrs)
- Intubation –> Oropharyngeal trauma
- Surgical trauma to local structures
- Primary or reactive haemorrhage
General complications of surgery: early (1d-1month)
- Secondary haemorrhage
- VTE
- Urinary retention
- Atelectasis and pneumonia
- Wound infection and dehiscence
- Antibiotic associated colitis
General complications of surgery: late (>1month)
- Scarring
- Neuropathy
- Failure or recurrence
General-post op complications: Haemorrhage classification
Primary: continuous bleeding starting during surgery
Reactive: bleeding at the end of surgery or early post-op. Secondary to increased CO and BP.
Secondary: Bleeding >24hr post-op. Usually due to infection
Clinical signs of significant post-op bleed?
Tachypnoea Tachycardia Hypotension (patients can have normal BP but be bleeding) Clamminess Cold peripheries Dizziness Confusion
On examination signs of significant post-op bleed?
Evidence of external bleeding Swelling Discoloration/bruising Tenderness around surgical site Peritonism
Classification of haemorrhagic shock?
Class 1 = Blood loss <750ml. HR <100, BP normal, RR 14-20, UO >30.
Class 2 = Blood loss 750-1500ml. HR 100-120, BP normal, RR 20-30, UO <20-30.
Class 3 = Blood loss 1500-2000ml. HR 120-140, BP decreased, RR 30-40, UO 5-20ml/hr.
Class 4 = Blood loss >2000ml. HR >140, BP decreased, RR >40, UO<5.
Practical tips for major haemorrhage?
- Re-assess regularly to ensure your management is effective
- Make use of the team around you to delegate tasks.
- All critically ill patients need continuous monitoring such as: BP, 3-Lead ECG, Oxygen Sats, HR, RR.
- communication
- Call for help early (SBAR handover)
- Ensure to prescribe medications/fluids
- Ensure you document everything.
Examination of suspected haemorrhage?
- If patient unconscious, check pulse + if breathing.
- If patient is unconscious or unresponsive and not breathing - start BLS and call 2222.
- Do an AVPU, how do they look. What is their breath like.
- Prep - Check operation + intraoperative blood loss.
A-E Assessment of post-operative bleed: A
- Airway. Look for speaking/evidence of stridor. If Head and Neck surgery consider senior surgical help ASAP.
- Maintaining airway. –> Head tilt, chin lift. Jaw thrust.
- Consider nasopharyngeal airway/oropharyngeal airway.
A-E Assessment of post-operative bleed: B
Breathing - O2 Sats of 95-98.
RR - Tachypnoea is very sensitive marker. (less haemoglobin therefore increased RR)
- Auscultate both lungs. Reduced air entry bilaterally. Unilateral reduced air entry. Palpate + percuss to assess chest expansion.
- Consider investigations such as ABG/Chest X-ray.
- High-flow oxygen through non-rebreathe mask.
- If patient unconscious + RR inadequate give assisted ventilation through bag-valve mask (BVM).
- Ventilate at rate of 12-15 breaths per minute (one every 4 seconds)
A-E Assessment of post-operative bleed: C
- Pulse - Check if tachy.
- BP - Hypotension
- Surgical drains/blood in situ
Check Cap refil time, clammy/pale. Pulse (tachycardic), BP: normal or hypotensive.
Intervention:
- Get IV access = 2 large bore. Need 18G cannulas so blood can run through quickly.
Urgent blood transfusion
- Ask for major haemorrhage guidelines
Administer IV fluids. Max 1-2 litres of fluid given. If becomes hypotensive again, they will need blood products too.
- Restore circulatory volume, correct electrolyte imbalances, perfuse kidneys.
Investigations
- Bloods/ G+S/CM. FBC, CRP, U+E, LFTs, Clotting.
- Record ECG
A-E Assessment of post-operative bleed: Disability
Blood glucose level
Assess pupils (size, equal, reactive to light)
Assess level of consciousness AVPU/GCS.
A-E Assessment of post-operative bleed: Exposure
inspection: UO , Temperature, Catheterise, Reverse hypothermia.
A-E Assessment of post-operative bleed: Document + Review
ABCDE findings + interventions and response the patient had.
A-E Assessment of post-operative bleed: Discuss
- Does the patient require further surgery for haemostasis
- Further assessments, investigations
- Does the patient need referral to HDU/ICU
- Should they be referred for a review by specialist doctor
- Changes to underlying conditions
Post-op Urinary retention causes?
Drugs: Opioids, epidural/spinal, anti-AChM
Pain: sympathetic activation –> Sphincter contraction
Psychogenic: hospital environment
Risk factors for post-op UO?
Male Increased age Neuropathy: e.g DM, ETOH BPH Surgery type: hernia/anorectal
Management of UO?
Conservative - Privacy - Ambulation - Void to running taps or in hot bath - Analgesia Medical - Catheterise ± gent 2.5mg/kg IV stat - TWOC = if failed, may be sent home with silicone catheter and urology output.