Care of surgical patients Flashcards

Question

Hypovolaemia + dehydration often occur together but what is the difference?

Answer 1

Hypovolaemia - loss of sodium + water, patient haemodynamically unstable, needs rapid fluid resus Dehydration - loss of water but not sodium, can lead to hypovolaemia, patient hypernatraemic, needs oral rehydration/slow IV fluids

Answer 2

Fluids that are secreted accumulate but aren't reabsorbed - isotonic contraction of ECF - dehydration + raised haematocrit When vomiting lose ECF into gut lumen (also leads to metabolic alkalosis with low blood volume, Cl- and K+)

Answer 3

``` Vomiting/NGT - hypocholaraemic hypokalaemic metabolic alkalosis Biliary drainage Diarrhoea/colostomy High or lower volume ileal losses Pure water loss e.g. fever, dehydration, hyperventilation (potential for hypernatraemia) Pancreatic drain Jejunal loss Inappropriate urinary loss Ongoing blood loss ```

Answer 4

Water 25-30 ml/kg/d Na+, K+, Cl- 1mmol/kg/d Glucose 50-100g/day

Answer 5

Colloids: no role in maintenance, risk of anaphylaxis, coagulopathy and higher cost Crystalloids lower risk and distribute throughout ECF as electrolytes go through membrane (whereas colloids larger proteins mean more likely to stay IV but this is theoretical)

Answer 6

Their [Na+] is similar to that of the ECF so only about 1/4 stays in the IV part of this. So e.g. for 100ml blood loss need 400ml 0.9% NaCl

Answer 7

Hypernatraemic, hypercholeraemic metabolic acidosis

Answer 8

Isotonic in the bag but the sugar is quickly metabolised so it becomes hypotonic so its the same as giving pure water -- distributes throughout all compartments, only about 1/12 is IV so bad for resuscitation but good for dehydration/hypernatraemia replacement

Answer 9

When patient can't meet needs enterally but don't have complex fluid/electrolyte issues -- aim to match normal daily requirements as much as poss -usually mix of salt + sugar. Hartmann's v good most similar to normal physiology but only low amount of K+ and can't give extra.

Answer 10

Correct dehydration | If reduced UO fluid challenge of 250-500ml over 15-30mins, can give up to 2L then need senior help

Answer 11

Check for third space losses, is there diuresis, tachypnoea/fever, high stoma output, diarrhoea, is fluid they are losing rich in electrolytes? So replace these as well as their normal daily requirements

Answer 12

Vomiting - Na+, H+, K+ Diarrhoea - Na+, K+, HCO3- All GI secretions - lots of K+

Answer 13

RhD antigen - 85% have it (RhD+) They will develop the RhD antibody, but not an issue as they don't attack their own blood But obv better to give matched blood

Answer 14

RhD- mother + RhD+ father Mother contracts RhD+ blood from foetus - develops antibodies - fine for first pregnancy In second pregnancy, the mother's anti-D antibodies cross the placenta and enter the foetus' RhD+ blood Antibody binds to RhD+ antigens - foetal immune system attacks + destroys its own RBCs - haemolytic disease of the newborn

Answer 15

Give RhD specific blood to women when they need transfusions Test during first pregnancy, if they are RhD - give injection of anti-RhD immunoglobulin around 28w, so foetal RhD+ RBCs get destroyed before mother exposed to + sensitised to them (which happens a bit later in pregnancy) - passive immunity

Answer 16

O- | No AB or Rh antigens on donor RBC surface, so even if recipient has antibodies to all they are unlikely to reject this

Answer 17

AB+ | No A, B or Rh antibodies in plasma so can't mount immune response

Answer 18

A - anti-B antibodies in plasma, A antigen in RBC, compatible with A and O B - anti-A antibody in plasma, B antigen in RBC, compatible with B and O AB - no antibodies in plasma, A + B antigens in RBC, compatible with any in emergency O - anti A and anti B antibodies in plasma, no antigens in RBC, compatible with type O

Answer 19

G&S: determines blood group, screens for atypical red cell antibodies, information saved XM: mix blood with donor blood to see if immune reaction occurs (may be done electronically), must do G&S first. For high risk procedures

Answer 20

1. 3 points of identification, consent, labelling bottle at bedside (not pre-labelled!), transfusion request form at bedside 2. CMV-negative blood to pregnant women, intra-uterine and to neonates up to 28d (congenital CMV infection - sensorineural deafness + cerebral palsy) 3. Irradiated blood products: reduce risk of G v H disease in risk people e.g. people having blood from family, Hodgkin's lymphoma, on chemo etc

Answer 21

70g/L for red cells (excluding haemorrhage and ACS), target 70-90g/L after transfusion Prescribe each unit individually, do observations before starts, 15m after and at 1h and completion Give via green or grey cannula otherwise haemolyses, give via blood giving set (not fluid set) Recommends single RBC transfusion for surgical patient without active bleeding. Normally when lose >500ml. If anaemia (Hb<100): in active bleeding ensure haemostats, G+S + XM, may transfuse PRC, check for haematinic deficiency Do observations before transfusion, after 15mins, at 1hr, at completion. Only give via 18G(green) or 16G (grey) cannula, otherwise the cell haemolyse, and only via blood giving set (has a filter)

Answer 22

Acute blood loss, chronic anaemia Hb< 70, Hb<100 in CVS disease, symptomatic anaemia Given over 2-4h, 1 unit should increase Hb by about 10g/L by increasing oxygen-carrying capacity Need G&S before any future transfusions - as may produce autoantibodies to other donor surface antigens

Answer 23

Haemorrhagic shock, profound thrombocytopenia/bleeding in thrombocytopenia, pre-op when platelets <50 Given over 30 mins Dangerous to give these in TTP and HIT Have highest risk of bacterial contamination

Answer 24

Contains clotting factors Used in DIC, haemorrhages (usually after 2u of PRC), prophylactically pre high risk surgeries Given over 30m

Answer 25

This is FFP enriched in fibrinogen so has lots of fibrinogen, vWF, factor VIII and fibronectin Used in DIC, emergencies in haemophilia when specific factors not available, massive haemorrhage/prophylaxis when low fibrinogen, von Willebrand's disease

Answer 26

In emergency reversal of anticoagulation in patients with severe bleeding or suspected intracerebral haemorrhage

Answer 27

* Transfusion reaction - even when XM. Fever, chills, hypotension, tachycardia, pyrexia, flank pain, haemoglobinuria -- due to antibodies binding to the antigen on donor - agglutination - complement - intravascular haemolysis * Blood group incompatibility - never event but still happens * Anaphylaxis or urticaria w/o anaphylaxis - reaction to foreign plasma proteins or antibodies to IgA * Febrile non-haemolytic transfusion reactions - temperature rise >1 degree, without other symptoms of transfusion reaction * Transfusion-related acute lung injury - due to leucocyte antibodies, causes dyspnoea, hypoxia and non-cardiogenic pulmonary oedema * Transfusion-related fluid overload * Bacterial contamination * Transfusion graft v host disease - rare, in immunocompromised (why you have to request irradiated blood)

Answer 28

Reduced intake - fasting, psych, pain Malabsorption or excess loss from gut Altered metabolism - burns sepsis trauma surgery cancer

Answer 29

Lack intake >5d, clinical appearance, unintentional WL >10% within 6m, BMI <18.5, specific deficiencies Blood: reduced albumin, transferrin or lymphocytes Pt should have MUST score calculated (Malnutrition Universal Screening Tool)

Answer 30

Protein deficiency - impaired wound healing + low immunity Skeletal muscle mass loss - extends to resp muscles Albumin low - oedema Small bowel mucosal atrophy - less absorption + bacterial translocate into blood Impaired mental function higher rate of post op complicaitons

Answer 31

I.e. no illness or trauma BG maintained by lowering insulin secretion + increasing glucagon Liver glycogen exhausted in a day but gluconeogenesis in liver + kidney increases using AAs from protein + glycerol from lipolysis Most glucose used by blood, most others use FAs and ketones

Answer 32

Sepsis: inability at mitochondria to fully oxidise substrates so less O2 consumed, FAs mobilised so high TAGs Severe trauma: lipids become major fuel as big rise in demands, peripheral glucose utilisation impaired so hyperglycaemia, muscle proteolysis to releases AAs, IL-1 reduces albumin synthesis so more acute phase proteins

Answer 33

Oral: selective diets e.g. low protein, liquidised normal diet, sip feeds with easily absorbed nutrients, supplements e.g. folic acid, vitamin K for prolonged ABs Tube feeds: e.g. swallowing difficulties, need more feed than patient can manage.

Answer 34

NG tube - unable to swallow e.g. unconscious, facial # NJ tube - as above + need post-pyloric feeding e.g. pancreatitis Gastrostomy - surgical or PEG. Often in stroke or obstructing lesion, CI in peritonitis, ascites Jejunostomy

Answer 35

High osmolality due to glucose AAs lipids minerals and vitamins, so it is to reduce risk of venous thrombosis

Answer 36

People malnourished with GIT inaccessible/non functional, and is likely to be like this for a long time

Answer 37

* Catheter problems - pneumothorax, brachial plexus injury, line infection, blocked/broken catheter, air embolism, central venous thrombosis * Metabolic issues - low phosphate or sodium/high sodium or glucose, over nutrition, fatty liver, deficiency of trace elements, deranged LFTs

Answer 38

Feed after starvation - sudden reversal from fat to CHO metabolism - insulin rises and so more cell uptake of glucose/phosphate/potassium/water - low phosphate, low K+ and low Mg2+ Main issue is low phosphate CF: HF, Resp failure, arrhythmias, rhabdomyolysis, white cell dysfunction, seizures, coma, sudden death M: monitor U+E, correct deficiencies

Answer 39

Subjective - ask them to grade Objective - tachycardia, tachypnoea, HTN, sweating, flushing, unwillingness to mobilise, agitation. Assess when mobile, taking deep breath and in bed Complications - atelectasis, pneumonia, poor mobilisation so less restoration of function

Answer 40

* Counselling pre-op about likely extent * Long acting IV analgesic * LA infiltration wound edges e.g. lidocaine + adrenaline (dont use at peripheries e.g. finger due to risk of AVN) * Regional n block * Epidural anaesthesia * NSAIDs before patient wakes

Answer 41

1. Non-opioid (paracetamol, ibuprofen) +/- adjuvant (co-codamol) 2. Opioid (codeine or dihydrocodeine, tramadol), stronger NSAIDs e.g. diclofenac, and paracetamol 3. Moderate-severe pain opiates (oxycodone, oramorph, morphine/diamorphine PCA), IV NSAIDs like diclofenac, as well as regular paracetamol (to reduce opiate requirements)

Answer 42

``` I-GRAB Interactions e.g. warfarin Gastric ulceration Renal impairment Asthma sensitivity Bleeding risk ```

Answer 43

Constipation, nausea, sedation, confusion, pruritus, resp depression, tolerance, dependence -- always prescribe laxatives + anti-emetics. prescribe anti-emetic PO+IV/IM -- renal impairment give oxycodone or fentanyl instead of morphine --if on reg opioites anyway give regular paracetamol to reduce requirements

Answer 44

Better bioavailability

Answer 45

Pros: analgesia tailored to pt requirement, risk of OD negligible, can accurately record how much used then convert into regular dose Cons: can prevent pt mobilising, not appropriate when dexterity poor/LDiffs

Answer 46

CBT, TENS, capsaicin cream (localised pain) | Pharm: gabapentin, amitriptyline, pregabalin

Answer 47

Local comps: haematoma, compartment syndrome, infection, DVT, MI Major comps: haemorrhage, anastomotic leakage, biliary leakage, abscess, gaseous distention from ileus, bowel obstruction, urinary retention, bowel ischaemia

Answer 48

DOAC first line (caution CKD) - direct factor Xa inhibitors (A, R and E) and direct thrombin inhibitor (D). Can start R + A alone, D and E need 5d of LMWH cover Warfarin next line - LMWH cover until INR therapeutic range (2-3). Teratogenic In cancer-ass DVT just use LMWH as less recurrence + its hard to maintain INR when having chemo Provoked DVT - continue anticoagulation for 3m If persistent RF + proximal DVT often need lifelong Cancer screening This is done to prevent propagation No direct evidence for anticoagulation in DVT, is done to help prevent propagation

Answer 49

``` DVT embolisation Right-sided mural thrombosis post-MI AF Neoplastic cells Fat cells e.g. long bone # ```

Answer 50

Wells' score 1 or less DVT unlikely so do D-dimer to exclude | If >1 DVT likely so do duplex USS

Answer 51

Well's score 4 or less do D-dimer to exclude (if this is positive do CTPA) If score >4 to CTPA to confirm

Answer 52

If haemodynamically stable then same as for DVT (i.e. first line DOAC, if using D need 5d LMWH, or if cancer then LMWH only) Haemodynamic compromise UFH, may need thrombolysis or embolectomy Recurrent PEs - IVC filter

Answer 53

Mechanical-encouraging mobilisation, calf muscle pump Maintaining hydration Stop COCP/HRT 4w pre elective surgery Anti-embolic stockings - all, except in peripheral arterial disease/oedema/skin issues Intermittent pneumatic compression - during surgery Pharm - LMWH unless eGFR <30 (use UFH). Usually give it pre-surgery unless CI, 4h after epidural due to risk of spinal haematomas

Answer 54

Pre-op: age, cancer, previous VTE, obese, smoker, pregnant, clotting disorder Intra-op: abdo/pelvis/hip/knee/spine surgery, no use of IPC, length Post-op: immobilisation, no of prophylaxis

Answer 55

If no risk of severe bleeding can do surgery with INR <2.5, unless v high risk of VTE INR <3 can continue warfarin for dental, cataract + minor skin ops In other surgeries stop warfarin 5d before to get INR <1.5, may need bridging with LMWH Also monitor TFTs and high snd low can affect warfarin DOACs: stop 24h before surgery, or 48h if higher risk. If low risk can restart this 6-12h post-op

Answer 56

Clopidogrel - usually stop Aspirin - usually continue Aspirin + clopidogrel - indicates high risk of CVS issues so consult specialty

Answer 57

Warfarin: If can wait 6-8h give vitamin K to reverse, if not then give PCC (prothrombin complex concentrate) Dabigatran: can use idarucizumab to reverse Rivaroxaban + abixaban no reversal agent

Answer 58

* IHD - silent * Renal - more impairment, less reserve * Peri-op strokes, lower limb ischaemia * Post-op infection * Risks of obesity for GA * Stress - more catabolic hormones which oppose insulin action making glycemic control harder * GA, low oral intake + post-op vomiting all disrupt control * DKA - raised WCC + amylase

Answer 59

1. Good control before surgery 2. Make them first on the list 3. Reduce SC basal insulin by 1/3 the night before, then stop morning of and start IV variable rate insulin infusion pump (has N saline + Actrapid). You adjust this hourly according to BG levels 4. Whilst NBM also give 5% dextrose, check BM regularly and continue until can E+D. Add K+ 5. Overlap SC + IV when changing back over

Answer 60

Metformin doesn't cause hypoglycaemia so stop it on the day cos of risk of lactic acidosis Sulfonylureas stopped on day until oral intake resumed Other drugs stopped 24h before, then put on sliding scale like for IDDM If glucose >13 can give small SC insulin dose If major op/long post-op NBM prob give insulin + glucose infusions

Answer 61

No special measures as they shouldn't become hypo/hyperglycaemic

Answer 62

* Adrenal suppression from HPA axis suppression long term use, so the usual increased cortisol secreted post-surgery doesn't happen causing circulatory collapse + hypotension (so have to increase dose) * The disease that requires them to take steroids e.g. cancer, RA, asthma * Long-term side effects e.g. HTN, DM, fatty liver, more infection risk, AVN, osteoporosis, electrolyte imbalances

Answer 63

For patients who have taken the equivalent of prednisolone 10mg or more daily within the past 3m, or high dose ICS. Usually give as a bolus: - Minor surgery 25mg hydrocortisone at induction of anaesthesia and resume normal meds post-op - Moderate usual dose pre-op, 25mg at induction and every 8h for 24h, then resume normal - Major usual dose pre-op, 50mg at induction, every 8h for 48-72h (until eat) then to normal If take <10mg prednisolone just continue normal dose

Answer 64

1. Consent is given voluntarily 2. Patient has capacity 3. Patient understands the nature of the treatment, its purpose, material risks + reasonable alternatives They may withdraw consent at any time and must be given time to reflect on their decisions - don't have to give a reason for refusal but obv ask without pressure in case they are hiding a fear/other issue

Answer 65

* growth hormone + thyroid hormones - inhibit insulin, promote catabolism * more glycogenolysis + gluconeogenesis * lipolysis-FA release * proteolysis - more AAs available for wound healing * ACTH release - more glucocorticoids - gluconeogenesis + protein catabolism * less insulin secretion - get hyperglycaemia + pseudo-diabetic state

Answer 66

o >50% rise in serum creatinine from baseline within last 7d/increase in serum creatinine by >26.5mmol/L within 48h/urine output <0.5ml/kg/hr for >6h o Stages by creatinine level: 1=1.5-2x, 2=2-3x, 3=>3x o Causes: pre renal commonest post op (sepsis, dehydration, bleeding, HF, liver failure-hepatorenal syndrome, damage to renal arteries), intra-renal (nephrotoxins like NSAIDs, ACEi, aminoglycosides or cisplatin, parenchymal disease), post-renal (ureteric-fibrosis, stones, tumours, bladder-acute retention, blocked catheter, urethral-BPH, stones) o Ix-US KUB in severe cases o Management – fluids if not overloaded, monitor output, regular bloods, drug rationalisation (potentially stop ACEI/ARB, NSAID, aminoglycoside, K+-sparing diuretics; alter/reduce metformin (lactic acidosis), diuretics, LMWH)

Answer 67

o ECG – All patients >70yrs or a history of chest pain, hypertension, or a heart murmur o LFT’s – Any alcohol intake over the expected amount o U&E’s – All patients >60yrs, currently taking antihypertensives, history of DM or renal problems, or a urine sample >1+ protein o Sickle cell test – If Afro Caribbean (and not previously tested) o CXR – Any recent pneumonia, to discuss with anaesthetist. Also ask about smoking + other resp problems o TFTs – Patients on thyroxine or having thyroid surgery o FBC – All patients >60yrs, or history of anaemia, any bleeding disorder, or sickle cell trait

Answer 68

Purpose is to identify co-morbidities that may cause anaesthetic/intra op/post-op complications  History – procedure scheduled + the issue briefly. Full PMH – CV (htn, exercise tolerance), resp disease (planning oxygenation), renal disease (issues like anaemia and biochemical disturbances can increase complications), endocrine disease (esp DM and thyroid disease), pregnancy risk, undiagnosed sickle cell if Afro-Caribbean; past surgical history, past anaesthetic history (were there issues, have they had PONV); full DH inc allergies!; FH (malignant hyperpyrexia important as autosomal dominant, causes muscle rigidity then rise in temp); SH for smoking and alcohol  Examination: general (underlying pathology) and airway examination (by anaesthetist obv, predict difficulty of intubation-degree of mouth opening, teeth + dentition, oropharynx-Mallampati classification, assess neck movement)  ASA grade: I=normal healthy, II=mild systemic disease, III=severe illness causing functional limitation, IV=severe systemic illness constant threat to life, V=moribund, E added if emergency operation  Investigations – depends on patient obviously + follow local guidelines, NICE have a traffic light table o Bloods: FBC (anaemia, thrombocytopenia – correct pre op to reduce CV events), U&E (renal function), LFTs (liver metabolism + synthesising function), clotting screen (identify deranged coagulation), G&S (if blood loss not anticipated but may be needed if more lost than usual) or XM (also need G+S, done if blood loss anticipated) o Imaging: ECG history of CV disease + baseline if there are post-op changes of ischaemia (may do echo if have murmur/heart sx), CXR only when absolutely necessary (e.g. resp illness without recent CXR, sig smoking history) o Others: pregnancy testing (women of child bearing age), sickle cell if have FH/ethnicity, MRSA swabs (all patients have this from nose/perineum/other sites, if identified they are given antiseptic body + hair wash and topical ointment from nostrils), urinalysis not routine (only if suspect DM/UTI)

Answer 69

MAOIs - 14d before Antiplatelets for primary prophylaxis - 7d before. (TMS says only clopidogrel, others fine. also different rules for heart surgery) Herbal medicines - 7d before Oral anticoagulants - 4d before (TMS-5d) Long-acting sulfonylureas - 3d. Short-acting sulfonylureas-24hrs [cf TMS says 24hr) Metformin-2d (cf TMS-day of) Solid foods 6hr, clear fluids 2hrs

Answer 70

• History: spontaneous bleeding/bruising, bleeding after minor procedures, menorrhagia, post-partum haemorrhage, recurrent epistaxis, known disorder, iatrogenic (aspirin, clopidogrel, warfarin, DOACs, corticosteroids) • Thrombocytopenia – repeat and request blood film, if severe (<50) signs like petechiae, epistaxis, purpura. HIT is possible but rare. o Causes are reduced production (haematinic deficiency, BM failure) or more removal (DIC, splenic sequestration) o Avoid NSAIDs and aspirin o Platelet transfusions are dangerous in TTP, HIT • Clotting screens for people with concerns: PT, APTT, TT/TCT (rarely used), fibrinogen • If known bleeding disorder contact haematologist

Answer 71

Document everything If child + life saving then have to give Optimise Hb pre-surgery e.g. oral iron, EPO, stopping antiplatelets/anticoagulants Intra-op: cell salvage, tranexamic acid

Answer 72

Life threatening organ dysfunction due to abnormal uncontrolled host response to infection - SOFA score of 2 or more + known/suspected infection score - early warning score system: the change is what's important, but 7+ is high risk - surgical pt 7Cs of causes: Chest, Cut, Catheter, Collections, Calves, Cannula, Central line - start sepsis 6, Abx within 1hr - source identification - escalating management with critical care - septic shock: sepsis with hypotension despite fluid resus, or needing inotropes to maintain BP

Answer 73

Pt details, RIPE A: Airway. Trachea, R & L bronchi B: Breathing. Uniform expansion? Edges of each lung? Look at the silhouettes C: Circulation. Cardiac size, great vessels, mediastinum and hila D: Disability. Fractures esp of ribs and shoulder girdle Everything else: air under diaphragm, edges-surgical emphysema, breast shadows, foreign bodies etc

Answer 74

Indicated in suspected bowel obstruction + erect CXR and suspected FB. Often not used as more appropriate options e.g. for RUQ pain do USS, for ?appendicitis do US then focussed CT 1. Name, type, projection, date taken, briefly assess quality 2. Air in wrong place – pneumoperitoneum/retroperitoneum, gas in biliary tree and portal vein 3. Bowel – dilated SB (more central, valvulae conniventes whole way across, less gas distally than normal, >3cm), dilated LB (more peripheral, haustra halfway, >6cm or about 7/8cm caecum), volvulus (sigmoid-coffee bean sign from LIF, caecal from RIF), hernia, evidence of bowel wall thickening 4. Calcification – clinically sig calcified structures like gallstones, renal stones, pancreatic and AAA; insignificant like costal cartilage, phleboliths, mesenteric LNs, prostate, vascular; and foetus 5. Disability (bones + solid organ) - #, sclerotic/lytic lesions, vertebral body height/alignment/bamboo spine, solid organ enlargement 6. Everything else – previous surgery/medical devices, foreign bodies, lung bases

Answer 75

Remember to request 2 views 90 degrees apart, usually AP and lateral/oblique. 1. Patient details 2. Image quality 3. Name specific bones, describe location of any abnormality (prox/middle/distal; head/neck/shaft; cortex/medulla. Can comment if see GP that is skeletally-immature 4. Specific structures: a. Bone alignment – changes in position suggesting # or dislocation b. Cortices – follow outline to see breaches which may indicate # or arthritis c. Texture e.g. disrupted trabecular pattern (it is normally in direction of the stress that bone withstands) d. Joint + cartilage – joint space, chondrocalcinosis, osteophytes e. Soft tissues – e.g. joint swelling may be seen