Scott's Notes - Surgery 2012v2 PDF

Surgery 2012 v2 Alasdair Scott BSc (Hons) MBBS MRCS PhD 2018 [email protected] www.scottsnotes.co.uk © Alasdair Scott, 2018 © Alasdair Scott, 2018 Table of Contents 1. Perioperative Management...............................................................

Surgery 2012 v2 Alasdair Scott BSc (Hons) MBBS MRCS PhD 2018 [email protected] www.scottsnotes.co.uk © Alasdair Scott, 2018 © Alasdair Scott, 2018 Table of Contents 1. Perioperative Management..................................................................................... 1 2. Fluids and Nutrition............................................................................................... 11 3. Trauma.................................................................................................................. 17 4. Upper GI Surgery.................................................................................................. 25 5. Hepatobiliary Surgery............................................................................................ 35 6. Lower GI Surgery.................................................................................................. 43 7. Perianal Surgery.................................................................................................... 59 8. Hernias.................................................................................................................. 65 9. Superficial Lesions................................................................................................ 70 10. Breast Surgery.................................................................................................... 81 11. Vascular Surgery................................................................................................. 86 12. Urology................................................................................................................ 95 13. Orthopaedics..................................................................................................... 110 14. Ear, Nose and Throat........................................................................................ 132 15. Ophthalmology.................................................................................................. 145 i © Alasdair Scott, 2018 © Alasdair Scott, 2018  Perioperative Management Contents Pre-Operative Assessment and Planning.............................................................................................................. 2 Specific Pre-operative Complications.................................................................................................................... 3 Anaesthesia........................................................................................................................................................... 4 Analgesia............................................................................................................................................................... 4 Enhanced Recovery After Surgery........................................................................................................................ 5 Surgical Complications.......................................................................................................................................... 5 Post-op Complications: General............................................................................................................................ 6 Post-op Complications: Specific............................................................................................................................ 7 Post-op Pyrexia...................................................................................................................................................... 8 Deep Venous Thrombosis..................................................................................................................................... 9 Other Common Post-Operative Presentations.................................................................................................... 10 1 © Alasdair Scott, 2018  Pre-Operative Assessment and Planning Aims Preparation Informed consent Assess risk vs. benefits NBM Optimise fitness of patient ≥2h for clear fluids, ≥6h for solids Check anaesthesia / analgesia type c̄ anaesthetist Bowel Prep Pre-op Checks: OP CHECS May be needed in left-sided ops Operative fitness: cardiorespiratory comorbidities § Picolax: picosulfate and Mg citrate Pills § Klean-Prep: macrogol Consent Not usually needed in right-sided procedures History Necessity is controversial as benefit of minimising § MI, asthma, HTN, jaundice post-op infection might not outweigh risks § Complications of anaesthesia: DVT, § Liquid bowel contents spilled during surgery anaphylaxis § Electrolyte disturbance Ease of intubation: neck arthritis, dentures, loose § Dehydration teeth § ↑ rate of post-op anastomotic leak Clexane: DVT prophylaxis Site: correct and marked Prophylactic Abx Use § GI surgery (20% post-op infection if elective) Drugs § Joint replacement Give 15-60min before surgery Anti-coagulants Regimens: (see local guidelines) Balance risk of haemorrhage c̄ risk of thrombosis § Biliary: Cef 1.5g + Met 500mg IV Avoid epidural, spinal and regional blocks § CR or appendicetomy: Cef+Met TDS § Vascular: co-amoxiclav 1.2g IV TDS AED § MRSA+ve: vancomycin Give as usual Post-op give IV or via NGT if unable to tolerate orally DVT Prophylaxis OCP / HRT Stratify pts according to patient factors and type of Stop 4wks before major / leg surgery surgery. Restart 2wks post-op if mobile Low risk: early mobilisation Med: early mobilisation + TEDS + 20mg enoxaparin β-Blockers High: early mobilisation + TEDS + 40mg enoxaparin + Continue as usual intermittent compression boots perioperatively. Prophylaxis started @ 1800 post-op May continue medical prophylaxis at home (up to 1mo) Pre-op Investigations Bloods ASA Grades Routine: FBC, U+E, G+S, clotting, glucose Normally healthy Specific Mild systemic disease § LFTs: liver disease, EtOH, jaundice Severe systemic disease that limits activity § TFT: thyroid disease Systemic disease which is a constant threat to life § Se electrophoresis: Africa, West Indies, Med Moribund: not expected to survive 24h even c̄ op Cross-match § Gastrectomy: 4u § AAA: 6u Cardiopulmonary Function CXR: cardiorespiratory disease/symptoms, >65yrs Echo: poor LV function, Ix murmurs ECG: HTN, Hx of cardiac disease, >55yrs Cardiopulmonary Exercise Testing PFT: known pulmonary disease or obesity Other Lat C-spine flexion and extension views: RA, AS MRSA swabs 2 © Alasdair Scott, 2018  Specific Pre-operative Complications Diabetes Jaundice Best to avoid operating in jaundiced pts. ↑ Risk of post-operative complications Use ERCP instead Surgery → stress hormones → antagonise insulin Pts. are NBM Risks ↑ risk of infection Pts. c̄ obstructive jaundice have ↑ risk of post-op renal IHD and PVD failure \ need to maintain good UO. Coagulopathy Pre-op ↑ infection risk: may → cholangitis Dipstick: proteinuria Venous glucose Pre-op + U+E: K Avoid morphine in pre-med Check clotting and consider pre-op vitamin K IDDM Give 1L NS pre-op (unless CCF) → moderate diuresis Urinary catheter to monitor UPO Practical Points Abx prophylaxis: e.g. cef+met Put pt. first on list and inform surgeon and anaesthetist Intra-op Some centres prefer to use GKI infusions Hrly UO monitoring Sliding scale may not be necessary for minor ops NS titrated to output § If in doubt, liaise c̄ diabetes specialist nurse Post-op Insulin Intensive monitoring of fluid status ± stop long-acting insulin the night before Consider CVP + frusemide if poor output despite NS Omit AM insulin if surgery is in the morning Start sliding scale § 5% Dex c̄ 20mmol KCl 125ml/hr Anticoagulated Patients § Infusion pump c̄ 50u actrapid Balance risk of haemorrhage c̄ risk of thrombosis § Check CPG hrly and adjust insulin rate Consult surgeon, anaesthetist and haematologist Check glucose hrly: aim for 7-11mM Very minor surgery may be undertaken w/o stopping Post-op warfarin if INR 10mM): treat as IDDM Low thromboembolic risk: e.g. AF Omit oral hypoglycaemics on the AM of surgery Stop warfarin 5d pre-op: need INR 2 § Monitor CPG Emergency Surgery Discontinue warfarin Steroids Vit K.5mg slow IV Request FFP or PCC to cover surgery Risks Poor wound healing COPD and Smoking Infection Adrenal crisis Risks Basal atelectasis Mx Aspiration Need to ↑ steroid to cope c̄ stress Chest infection Consider cover if high-dose steroids w/i last yr Major surgery: hydrocortisone 50-100mg IV c̄ pre- Pre-op med then 6-8hrly for 3d. CXR Minor: as for major but hydrocortisone only for 24h PFTs Physio for breathing exercises Quit smoking (at least 4wks prior to surgery) 3 © Alasdair Scott, 2018 Anaesthesia Analgesia Principals and Practical Conduct Necessity Aims: hypnosis, analgesia, muscle relaxation Pain → autonomic activation → arteriolar constriction → Induction: e.g. IV propofol ↓ wound perfusion → impaired wound healing Muscle Relaxation Pain → ↓ mobilisation → ↑ VTE and ↓ function § Depolarising: suxamethonium Pain → ↓ respiratory excursion and ↓ cough → § Non-depolarising: vecuronium, atracurium atelectasis and pneumonia Airway Control: ET tube, LMA Humanitarian considerations Maintenance § Usually volatile agent added to N2O/O2 mix General Guidance § E.g. halothane, enflurane Give regular doses at fixed intervals End of Anaesthesia Consider best route: oral when possible § Change inspired gas to 100% O2 PCA should be considered: morphine, fentanyl § Reverse paralysis: neostigmine + atropine Follow stepwise approach (prevent muscarinic side effects) Liaise c̄ Acute Pain Service Pre-medication: 7As Pre-Op Epidural anaesthesia: e.g. c̄ bupivacaine Anxiolytics and Amnesia: e.g. temazepam Analgesics: e.g. opioids, paracetamol, NSAIDs Anti-emetics: e.g. ondansetron 4mg / metoclop 10mg End-Op Antacids: e.g. lansoprazole Infiltrate wound edge c̄ LA Anti-sialogue e.g. glycopyrolate (↓ secretions) Infiltrate major regional nerves c̄ LA Antibiotics Post-Op: stepwise approach Regional Anaesthesia 1. Non-opioid ± adjuvants May be used for minor procedures or if unsuitable for § Paracetamol GA § NSAIDs Nerve or spinal blocks - Ibuprofen: 400mg/6h PO max § CI: local infection, clotting abnormality - Diclofenac: 50mg PO / 75mg IM Use long-acting agents: e.g. bupivacaine 2. Weak opioid + non-opioid ± adjuvants § Codeine Complications of Anaesthesia § Dihydrocodeine § Tramadol Propofol Induction 3. Strong opioid + non-opioid ± adjuvants Cardiorespiratory depression § Morphine: 5-10mg/2h max § Oxycodone Intubation § Fentanyl Oro-pharyngeal injury c̄ laryngoscope Oesophageal intubation Spinal or Epidural Anaesthesia ↓ SE as drugs more localised Loss of pain sensation st 1 line for major bowel resection Urinary retention Caution Pressure necrosis § Respiratory depression Nerve palsies § Neurogenic shock → ↓BP Loss of muscle power Corneal abrasion No cough → atelectasis + pneumonia Malignant Hyperpyrexia Rare complication ppted by halothane or suxamethonium AD inheritance Rapid rise in temperature + masseter spasm Rx: dantrolene + cooling Anaphylaxis Rare Possible triggers § Antibiotics § Colloid § NM blockers: e.g. vecuronium 4 © Alasdair Scott, 2018 Enhanced Recovery After Surgery Surgical Complications ERAS Immediate (1mo) intervention Scarring Neuropathy Failure or recurrence Pre-op: optimisation Aggressive physiological optimisation § Hydration § BP (↑ / ↓) § Anaemia § DM § Co-morbidities Smoking cessation: ≥4wks before surgery Admission on day of surgery, avoidance of prolonged fast Carb loading prior to surgery: e.g. carb drinks Fully informed pt., encouraged to participate in recovery Intra-op: ↓ 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 Rx of pain and nausea Early mobilisation and physiotherapy Early resumption of oral intake (inc. carb drinks) Early discontinuation of IV fluids Remove drains and urinary catheters ASAP 5 © Alasdair Scott, 2018  Post-op Complications: General Haemorrhage Classification Wound Infection Primary: continuous bleeding starting during 5-7d post-op surgery Organisms: S. aureus and Coliforms Reactive § Bleeding at the end of surgery or early Operative Classification post-op Clean: incise uninfected skin w/o opening viscus O § 2 to ↑ CO and BP Clean/Cont: intra-op breach of viscus (not colon) Secondary Contaminated: breach of viscus + spillage or opening of § Bleeding >24h post-op colon § Usually due to infection Dirty: site already contaminated – faeces, pus, trauma Risk Factors Post-op Urinary Retention Pre-operative § ↑ Age Causes § Comorbidities: e.g. DM Drugs: opioids, epidural/spinal, anti-AChM § Pre-existing infection: e.g. appendix perforation Pain: sympathetic activation → sphincter § Pt. colonisation: e.g. nasal MRSA contraction Operative Psychogenic: hospital environment § Op classification and wound infection risk § Duration § Technical: pre-op Abx, asepsis Risk Factors Post-operative Male § Contamination of wound from staff ↑ age Neuropathy: e.g. DM, EtOH Mx BPH Regular wound dressing Surgery type: hernia and anorectal Abx Abscess drainage Mx Conservative § Privacy § Ambulation Wound Dehiscence § Void to running taps or in hot bath § Analgesia Presentation Catheterise ± gent 2.5mg/kg IV stat Occurs ~10d post-op TWOC = Trial w/o Catheter Preceded by serosanguinous discharge from wound § If failed, may be sent home c̄ silicone catheter and urology outpt. f/up. Risk Factors Pre-Operative Factors § ↑ age Pulmonary Atelectasis § Smoking Occurs after every nearly every GA § Obesity, malnutrition, cachexia Mucus plugging + absorption of distal air → § Comorbs: e.g. BM, uraemia, chronic cough, Ca collapse § Drugs: steroids, chemo, radio Operative Factors Causes § Length and orientation of incision Pre-op smoking § Closure technique: follow Jenkin’s Rule Anaesthetics ↑ mucus production ↓ mucociliary § Suture material clearance Post-operative Factors Pain inhibits respiratory excursion and cough § ↑ IAP: e.g. prolonged ileus → distension § Infection § Haematoma / seroma formation Presentation w/i first 48hrs Mx Mild pyrexia Replace abdo contents and cover c̄ sterile soaked gauze Dyspnoea IV Abx: cef+met Dull bases c̄ ↓AE Opioid analgesia Call senior and arrange theatre Mx Repair in theatre Good analgesia to aid coughing § Wash bowel Chest physiotherapy § Debride wound edges § Close c̄ deep non-absorbable sutures (e.g. nylon) May require VAC dressing or grafting 6 © Alasdair Scott, 2018  Post-op Complications: Specific General Surgery Vascular Cholecystectomy Arterial Surgery Conversion to open: 5% Thrombosis and embolisation CBD injury: 0.3% Anastomotic leak Bile leak Graft infection Retained stones (needing ERCP) Fat intolerance / loose stools Aortic Surgery Gut ischaemia Inguinal Hernia Repair Renal failure Early Aorto-enteric fistula Haematoma / seroma formation: 10% Anterior spinal syndrome (paraplegia) Intra-abdominal injury (lap) Emboli → distal ischaemia (trash foot) Infection: 1% Urinary retention Breast Late Arm lymphoedema § Recurrence: 0.5% Skin necrosis § Ischaemic orchitis: 0.5% Seroma § Chronic groin pain / paraesthesia: 10-20% Urological Appendicectomy Sepsis Abscess formation Uroma: extravasation of urine Fallopian tube trauma Right hemicolectomy (e.g. for carcinoid, caecal Prostatectomy necrosis) Urinary incontinence Erectile dysfunction Colonic Surgery Retrograde ejaculation Early Prostatitis § Ileus § Anastomotic leak § Enterocutaneous fistulae ENT § Abdominal or pelvic abscess Late Thyroidectomy § Adhesions → obstruction Wound haematoma → tracheal obstruction § Incisional hernia Recurrent laryngeal N. trauma → hoarse voice § Transient in 1.5% Post-op Ileus § Permanent in 0.5% Causes § R commonest (more medial) § Bowel handling Hypoparathyroidism → hypocalcaemia § Anaesthesia Thyroid storm § Electrolyte imbalance Hypothyroidism Presentation § Distension Tracheostomy § Constipation ± vomiting Stenosis § Absent bowel sounds Mediastinitis Rx Surgical emphysema § IV fluids + NGT § TPN if prolonged Orthopaedic Surgery Anorectal Surgery Fracture Repair Anal incontinence Mal-/non-union Stenosis Osteomyelitis Anal fissure Avascular necrosis Compartment syndrome Small Bowel Surgery Short gut syndrome (≤250cm) Hip Replacement Deep infection Splenectomy VTE O Gastric dilatation (2 gastric ileus) Dislocation § Prevent c̄ NGT Nerve injury: sciatic, SGN Thrombocytosis → VTE Leg length discrepancy Infection: encapsulated organisms Cardiothoracic Surgery Pneumo-/haemo-thorax Infection: mediastinitis, empyema 7 © Alasdair Scott, 2018  Post-op Pyrexia Causes Pneumonia Early: 0-5d post-op Cause Blood transfusion Anaesthesia → atelectasis O Physiological: SIRS 2 to trauma, 0-1d Pain → ↓ cough Pulmonary atelectasis: 24-48hrs Surgery → immunosuppression Infection: UTI, superficial thrombophlebitis, cellulitis Drug reaction Rx Chest physio: encouraging coughing Delayed: >5d post-op Good analgesia Pneumonia Abx VTE: 5-10d Wound infection: 5-7d Anastomotic leak: 7d Collection Collection: 5-20d Presentation Malaise Examination of Post-Op Febrile Pt. Swinging fever, rigors Observation chart, notes and drug chart Localised peritonitis Wound Shoulder tip pain (if subphrenic) Abdo + DRE Legs Locations Chest Pelvic Lines Subphrenic Urine Paracolic gutters Stool Lesser sac Hepatorenal recess (Morrison’s space) Small bowel (interloop spaces) Ix Urine: dip + MCS Ix Blood: FBC, CRP, cultures ± LFTs FBC, CRP, cultures Cultures: wound swabs, CVP tip for culture US, CT CXR Diagnostic lap Rx Abx Drainage / washout Cellulitis Acute infection of the subcutaneous connective tissue Cause: β-haemolytic Streps + staph. aureus Presentation Pain, swelling, erythema and warmth Systemic upset ± lymphadenopathy Rx Benpen IV Pen V and fluclox PO 8 © Alasdair Scott, 2018  Deep Venous Thrombosis Epidemiology Preventing DVT DVTs occur in 25-50% of surgical patients without thromboprophylaxis Pre-Op Pre-op VTE risk assessment Risk Factors: Virchow’s Triad TED stockings Blood Contents Aggressive optimisation: esp. hydration § Surgery → ↑ plats and ↑ fibrinogen Stop OCP 4wks pre-op § Dehydration § Malignancy Intra-Op § Age: ↑ Minimise length of surgery Blood Flow Use minimal access surgery where possible § Surgery Intermittent pneumatic compression boots § Immobility § Obesity Post-Op Vessel Wall LMWH § Damage to veins: esp. pelvic veins § Previous VTE Early mobilisation Good analgesia Physio Signs Adequate hydration Peak incidence @ 5-10d post-op 65% of below knee DVTs are asymptomatic Calf warmth, tenderness, erythema, swelling Mild pyrexia Pitting oedema Differential Cellulitis Ruptured Baker’s cyst Ix D-Dimers: sensitive but not specific Compression US (clot will be incompressible) Thrombophilia screen if: § No precipitating factors § Recurrent DVT § Family Hx Dx Assess probability using Wells’ Score Low-probability → perform D-dimers § Negative → excludes DVT § Positive → Compression US Med / High probability → Compression US Rx Anticoagulate Therapeutic LMWH: enoxaparin 1.5mg/kg/24h SC Start warfarin using Tait model: 5mg OD for first 4d Stop LMWH when INR 2.5 Duration § Below knee: 6-12wks § Above knee: 3-6mo § On-going cause: indefinite Graduated Compression Stockings Consider for prevention of post-phlebitic syndrome 9 © Alasdair Scott, 2018  Other Common Post-Operative Presentations Dyspnoea / Hypoxia Hypotension Causes Immediate Mx Previous lung disease Tilt bed head down, give O2 Atelectasis, aspiration, pneumonia Assess fluid status LVF PE Causes: CHOD Pneumothorax (e.g. due to CVP line insertion) Cardiogenic Pain → hypoventilation § MI § Fluid overload Ix Hypovolaemia FBC, ABG § Inadequate replacement of fluid losses CXR § Haemorrhage ECG Obstructive § PE Distributive Rx § Sepsis Sit up, give O2, monitor SpO2 § Neurogenic shock Rx cause Mx Hypovolaemia → fluid challenge Reduced Urine Output § 250-500ml colloid over 15-30min Haemorrhage → return to theatre Causes Sepsis → fluid challenge, start Abx Post-renal Overload → frusemide § Commonest cause Neurogenic → NA infusion § Blocked / malsited catheter § Acute urinary retention Pre-renal: hypovolaemia Hypertension Renal: NSAIDs, gentamicin Continue anti-hypertensives during peri-operative Anuria usually = blocked or malsited catheter period Oliguria usually = inadequate fluid replacement Causes Mx Pain Information Urinary retention § Op Hx Previous HTN § Obs chart: UO § Drug chart: nephrotoxins Rx Examination Rx cause § Assess fluid status § Examine for palpable bladder May use labetalol 50mg IV every 5min (200mg max) § Inspect drips, drains, stomas, CVP Action § Flush c̄ 50ml NS and aspirate back Acute Confusional State § Fluid challenge Agitation, disorientation, attempts to leave hospital Common Causes: DELIRIUM Nausea and Vomiting Drugs: opiates, sedatives, L-DOPA Causes Eyes, ears and other sensory deficits § Obstruction Low O2 states: MI, stroke, PE § Ileus Infection § Emetic drugs: e.g. opioids Retention: stool or urine Consider NGT, AXR and ondansetron 4mg IV TDS Ictal Under- hydration / -nutrition Metabolic: Na, AKI, glucose, EtOH withdrawal ↓ Na What was pre-op level? Mx Common Causes: May need sedation: midazolam / haldol § S(I)ADH: pain, nausea, opioids, stress Nurse in well-lit environment § Over administration of IV fluids Rx cause Correct slowly § Acute: 1mM/h § Chronic:15mM/d 10 © Alasdair Scott, 2018  Fluids and Nutrition Contents Fluid Homeostasis............................................................................................................................................... 12 Crystalloid............................................................................................................................................................ 13 Colloid.................................................................................................................................................................. 13 Fluid Problems..................................................................................................................................................... 14 Nutrition................................................................................................................................................................ 15 Refeeding Syndrome........................................................................................................................................... 16 11 © Alasdair Scott, 2018  Fluid Homeostasis Body Composition Fluid Balance Total water: 60% of 70kg = 42L § 2/3 intracellular = 28L Input Output § 1/3 extracellular = 14L Water 1500 Urine 1500 - Plasma = 3L (21% of ECF) Food 1000 Stool 300 - Interstitial = 10L Metabolism 300 Insensible 1000 - Transcellular = 1L - lungs - sweating Total 2800ml Total 2800ml Starling’s Forces = = 40ml/kg/d 40ml/kg/d Osmotic Pressure Pressure which needs to be applied to prevent the Other Values inflow of water across a semipermeable membrane. Minimum UO = 0.5ml/kg/h = ~30ml/h i.e. the ability of a solute to attract water. Na requirement = 1.5-2mmol/kg/d = 100mmol/d Oncotic pressure: form of osmotic pressure exerted K requirement = 1mmol/kg/d = 60mM/d by proteins. Fluid Regimens Hydrostatic Pressure Pressure exerted by a fluid at equilibrium due to the Daily Requirements force of gravity. + 3L dex-saline c̄ 20mM K in each bag + 1L NS + 2L dex c̄ 20mM K in each bag Each bag over 8h = 125ml/h Distribution Distribution between the ECF and ICF is driven by Replace other losses differences in osmotic pressure only. Vomiting and Diarrhoea Distribution w/i the ECF is determined by Starling’s NGT forces. Drains § Capillary and interstitial oncotic pressure. O § Capillary and interstitial hydrostatic pressure. Fever (+500ml for each C) § Filtration coefficient (capillary permeability) Tachypnoea High-output stomas 3rd Space Losses → ↓ ECF rd Bowel obstruction → ↓ fluid reabsorption → 3 space CVP Monitoring loss Indicates RV preload and depends on Sudden diuresis on day 2-3 post op = recovery of § Venous return ileus § Cardiac output rd Peritonitis → ascites → 3 space loss ↑ CVP § ↑ circulating volume § ↓CO: i.e. pump failure ↓ CVP § ↓ circulating volume Normal value: ~5-10cmH2O Single reading is not as useful as serial measurements before and after fluid challenge. § Unchanged: hypovolaemic § ↑ that reverses after 30min: euvolaemic § Sustained ↑ >5cmH2O: overload / failure Passive leg raising may be more useful than fluid challenge in determining response to fluids. § Sustained ↑ in CVP suggests heart failure. 12 © Alasdair Scott, 2018 Crystalloid Colloid Normal Saline Physiology Contain large molecular wt. molecules Contents Gelatin 0.9% NaCl = 9g/L Dextrans 154mmol NaCl Preserves oncotic pressure \ remains intravascular → preferential ↑ in intravascular volume pH: 5-6 Synthetic Use Gelofusin Normal daily fluid requirements + replace losses Volplex Haemaccel Voluven 5% Dextrose Natural Contents Albumin 50g dextrose /L Blood Use Use Normal daily fluid requirements Fluid challenge: 250-500ml over 15-30min Hypovolaemic shock Mount Vernon Formula § (wt. x %burn)/2 = ml colloid per unit time Dextrose-Saline Problems Contents Anaphylaxis 4% dextrose = 40g/L Volume overload 0.18% NaCl = 31mM NaCl Can interfere c̄ cross-matching therefore take blood for x-match before using. Use Normal daily fluid requirements Hartmann’s / Ringer’s Lactate Contents Na: 131mM Cl: 111mM K: 5mM Ca: 2.2mM Lactate / HCO3: 29mM Use Resuscitation in trauma pts. st Parkland’s formula: 4 x wt x %burn = mL in 1 24hrs pH pH = 6.5 but Hartmann’s is an alkalinising solution Lactate is not an acid in itself: it’s a conjugate base Given exogenously as sodium lactate Lactate metabolised in liver → HCO3 production The Cori Cycle Daily Requirements + 3L dex-saline c̄ 20mM K in each bag + 1L NS + 2L dex c̄ 20mM K in each bag Each bag over 8h = 125ml/h Problems Give 1L NS → ~210ml remaining intravascularly Give 1L D5W → ~70ml remaining intravascularly Acidosis or electrolyte disturbances Fluid overload 13 © Alasdair Scott, 2018  Fluid Problems Assessing Fluid Status Ileostomy Hx: balance chart, surgery, other losses, thirsty Ileal fluid composition Impression: drowsy, alert § Na: 130mM Inspection: drips, drains, stomas, catheters, CVP § Cl: 110mM § K: 10mM Examination § HCO3: 30mM Normal output: 10-15mL/Kg/d = ~700ml/d IV volume § CRT High output = >1000ml/d § HR Ileum will adapt to limit fluid and electrolyte losses § BP lying and standing Fluids § JVP § 0.9% NS +KCl Tissue perfusion § Daily requirements + replaces losses, titrated to § Skin turgor UO § Oedema: ankle, pulmonary, ascites § Serial U+Es guide electrolyte replacement § Mucus membranes High Output End-organ § Loperamide § UO, ↑U+Cr § Codeine § Consciousness § Lactate Reduced Urine Output Post-op Other Tests PCWP: indirect measure of left atrial pressure Causes CVP Post-renal § Commonest cause Post-operative Fluids § Blocked / malsited catheter § Acute urinary retention Problems Pre-renal: hypovolaemia Renal: NSAIDs, gentamicin ↑ADH, ↑aldosterone, ↑cortisol → Na +H2O conservation + Anuria usually = blocked or malsited catheter ↑ K : tissue damage, transfusion, stress hormones Oliguria usually = inadequate fluid replacement Solutions Mx Use UO (aim>30ml/h) to guide fluid replacement but may need to ↓ maintenance fluids to 2L first 24h post- Information op § Op Hx + § Obs chart: UO Avoid K supplementation for first 24h post-op § Drug chart: nephrotoxins Examination Cardiac or Renal Failure § Assess fluid status § Examine for palpable bladder Problem § Inspect drips, drains, stomas, CVP RAS activation → Na and H2O retention Action § Flush c̄ 50ml NS and aspirate back Solution § Fluid challenge Avoid fluids c̄ Na → give 5% dextrose Suspect Catheter Problem Flush c̄ 50ml NS and aspirate back Bowel Obstruction Pts. have significant third space losses c̄ loss of both water and electrolytes. Suspect Pre-renal Problem Likely to need significantly more than standard daily Fluid challenge requirements. § 250-500ml colloid bolus over 15-30min Regimen § Look for CVP or UO response w/i minutes § 0.9% NS c̄ 20-40mm KCl added to each bag § Titrate rate of fluid therapy to clinical findings on serial examination. § Serial U+Es guide electrolyte replacement Pancreatitis Inflammation → significant fluid shift into the abdomen. Pts require aggressive fluid resuscitation and maintenance § Insert urinary catheter and consider CVP monitoring § 0.9% NS c̄ 20-40mm KCl added to each bag § Keep UO >30ml/h § Serial U+Es guide electrolyte replacement 14 © Alasdair Scott, 2018  Nutrition Assessment Parenteral Nutrition May be “Total” or used to supplement enteral feeding Clinical Combined c̄ H2O to deliver total daily requirements Hx § Wt. loss § Diet Indications Examination Prolonged obstruction or ileus (>7d) § Skin fat High output fistula § Dry hair Short bowel syndrome § Pressure sores Severe Crohn’s § Cheilitis Severe malnutrition 2 § Wt. and BMI (100 ↔ 30 >120 ↓ 5-20 Confused Examination 4 >40 >2000 >35 >140 ↓↓ 1.5L of blood in chest cavity Usually caused by disruption of hilar vessels Sternal # Usually MVA driver vs. steering wheel Presentation Risk of mediastinal injury Signs of chest wall trauma Rx ↓BP § Analgesia, admit, observe ↓ expansion § Cardiac monitor ↓ breath sounds and ↓VR § Troponin: rule out myocardial contusion Stony dull percussion Pulmonary Contusion Mx Usually due to rapid deceleration injury or shock waves X-match 6u May → ARDS Large-bore chest drain c̄ hep saline for autotransfusion Pres: dyspnoea, haemoptysis, respiratory failure Thoracotomy if >1.5L or >200ml/h Ix § CXR: opacification Flail Chest § Serial ABGs: ↓ PaO2:FiO2 ratio Ant. or lat. # of ≥2 adjacent ribs in ≥2 places Rx: O2, ventilate if necessary Flail segment moves paradoxically c̄ respiration ↓ Oxygenation Myocardial Contusion § Underlying pulmonary contusion Direct blunt trauma over precordium § ↓ Ventilation of affected segment Ix § ECG: abnormal, arrhythmias Ix § ↑ troponin CXR / CT chest: pulmonary contusion (white) Rx: bed rest, cardiac monitoring, Rx arrhythmias Serial ABGs: ↓PaO2:FiO2 ratio Contained Aortic Disruption Rx Rapid deceleration injury (80% immediately fatal) O2 Pres: initially stable but → hypotensive Good analgesia: PCA, epidural Ix Persistent respiratory failure: PPV § CXR: wide mediastinum, deviation of NGT § CT Cardiac Tamponade Rx: cardiothoracic consult Disruption of myocardium or great vessels → blood in the pericardium → ↓ filling and contraction → shock Diaphragmatic Injury th Usually results from penetrating trauma Consider in penetrating injuries below 5 rib or high energy compression. Presentation Ix: CXR (visceral herniation), CT Beck’s Triad § ↑ JVP / distended neck veins Oesophageal Disruption § ↓ BP Usually penetrating trauma § Muffled heart sounds → mediastinitis Pulsus paradoxus: SBP fall of >10mmHg on inspiration Ix Kussmaul’s sign: ↑ JVP on inspiration § CXR: pneumomediastinum, surgical Intensely restless pt. emphysema § CT Ix US: FAST or transthoracic echo Tracheobronchial Disruption CXR: enlarged pericardium Presentation ↑CVP >12mmHg § Persistent pneumothorax ECG: low voltage QRS ± electrical alternans § Pneumomediastinum Rx: thoracotomy Mx Pericardiocentesis: spinal needle in R subxiphoid space O aiming at 45 towards the R tip of left scapula Thoracotomy may be needed 20 © Alasdair Scott, 2018  Abdominal Trauma Mechanisms Damage Control Surgery Penetrating § All require exploration as tract may be deeper Aim than it appears. Early Mx of abdominal trauma should focus on “damage Blunt control” to limit physiological stress. § Have a high index of suspicion for taking to § Control haemorrhage: ligation and packing theatre. § Control contamination § Stabilise in ITU Specific Ix Spleen Urine Dip Kehr’s Sign O Haematuria suggests injury to renal tract § Shoulder tip pain 2 to blood in the peritoneal cavity. § Left Kehr sign is classic symptom of ruptured FAST Scan spleen Replacing DPL in most centres Classification Check for fluid in the abdomen, pelvis and pericardium. § 1: capsular tear § 90% sensitive for free fluid § 2: Tear + parenchymal injury Can be extended to look for pneumothoraces § 3: Tear up to the hilum § 4: Complete fracture Diagnostic Peritoneal Lavage Mx Advantages and Disadvantages § Haemodynamically unstable: laparotomy § 98% sensitive for intra-abdominal haemorrhage § Stable 1-3: observation in HDU § Useful if FAST unavailable § Stable 4: consider laparotomy § May be better for identifying injury to hollow viscus - Suture lac or partial / complete § Unable to identify retroperitoneal injury splenectomy Insert urinary catheter and NGT § Decompression to minimise risk of injury Liver Midline incision through skin and fascia @ 1/3 distance Conservative if capsule is intact form umbilicus to pubic symphysis (arcuate line). Suture laceration Carefully dissect to the peritoneum and insert a urinary Partial hepatectomy catheter. Packing Instil 10ml/kg warmed Hartmann’s Drain fluid back into bag and send sample to lab. 3 Bowel +ve = >100,000 RBCs/mm , bile/intestinal contents Resection may be required Indications for Laparatomy Bladder (often assoc. c̄ pelvic injury) Unexplained shock Intraperitoneal rupture requires laparoscopic repair c̄ Peritonism: rigid silent abdomen urethral and suprapubic drainage Evisceration: bowel or omentum Extraperitoneal rupture can be treated conservatively c̄ Radiological evidence of intraperitoneal gas urethral drainage. Radiological evidence of ruptured diaphragm Give prophylactic Abx Gunshot wounds +ve DPL or CT Urethra Classification § Anterior - Spongy urethra (penile + bulbar) - Occur following straddling injuries or instrumentation § Posterior - Membranous urethra - Occur following pelvic #s Presentation § Often assoc. c̄ pelvic fracture § Blood in the urethral meatus or scrotum § Perineal bruising § High-riding prostate § Inability to micturate + palpable bladder Ix § Retrograde urethrogram Mx § Suprapubic catheter § Surgical repair 21 © Alasdair Scott, 2018  Head Injury Epidemiology History Head injury, alone or in combination c̄ other injuries, is LOC the commonest cause of trauma death (50%) Amnesia: anterograde worse Nausea / vomiting Primary Brain Injury Fits Occurs at time of injury and is a result of direct or indirect Focal neurology injury to brain tissue. Mechanism Drugs: e.g. antiplats, warfarin Diffuse Concussion / Mild Traumatic Brain Injury Examination § Temporary ↓ in brain function GCS: E4, V5, M6 § Headache, confusion, visual symptoms, amnesia, § 3-8 = coma nausea § 9-12 = moderate head injury Diffuse Axonal Injury § 13-15 = mild head injury § Shearing forces disrupt axons Scalp lacerations § May → coma and persistent vegetative state § Autonomic dysfunction → fever, HTN, sweating Basal Skull # CSF rhinorrhoea or otorrhoea (Test: halo sign) Focal Battle sign: bruised mastoid Contusion Pando sign: bilateral orbital bruising § E.g. coup and contra-coup Haemotympanum § May have focal neurological deficit Ix Intracranial Haemorrhage C-spine § Extradural CT Head § Subdural § Basal or other skull # § Subarachnoid § Amnesia: > 30min retrograde (before event) § Parenchymal haemorrhage and laceration § Neurological deficit: e.g. seizures § GCS: 5min ↑ ICP § Abnormalities on imaging Infection § Difficult to assess: EtOH, post-ictal § Not returned to GCS 15 after imaging Monroe-Kelly Doctrine § CNS signs: persistent vomiting, severe headache Cranium is rigid box \ total volume of intracranial Neuro obs: half hrly until GCS 15/15 contents must remain constant if ICP is not to change. § GCS, pupils, TPR, BP ↑ in volume of one constituent → compensatory ↓ in Analgesia: codeine phosphate 30-60mg PO/IM QDS another: Suture scalp lacs § CSF Abx: if open / base of skull # § Blood (esp. venous) These mechanisms can compensate for a volume Intubate if change of ~100ml before ICP ↑. GCS ≤ 8 § As autoregulation fails, ICP ↑ rapidly → herniation. PaO2 6. Colapinto needle creates tract through liver parenchyma which is expand using a balloon and Open stomach, find bleeder and underrun vessel. maintained by placement of a stent. NA. Avoid 0.9% NS in uncompensated liver disease (worsens Used prophylactically or acutely if endoscopic therapy ascites). Use blood/albumin for resus and 5% dex for fails to control variceal bleeding. maintenance. 30 © Alasdair Scott, 2018 Perforated Peptic Ulcer Gastric Outlet Obstruction Pathophysiology Cause Perforated duodenal ulcer is commonest Late complication of PUD → fibrotic stricturing st § 1 part of the duodenum: highest acid conc Gastric Ca § Ant. perforation → air under diaphragm § Post. perforation can erode into GDA → bleed Presentation § ¾ of duodenum retroperitoneal \ no air under Hx of bloating, early satiety and nausea diaphragm if perforated. Outlet obstruction Perforated GU § Copious projectile, non-bilious vomiting a few Perforated gastric Ca hrs after meals. § Contains stale food. Presentation § Epigastric distension + succussion splash Sudden onset severe pain, beginning in the epigastrium and then becoming generalised. Ix Vomiting ABG: Hypochloraemic hypokalaemic met alkalosis Peritonitis AXR § Dilated gastric air bubble, air fluid level Differential § Collapsed distal bowel Pancreatitis OGD Acute cholecystitis Contrast meal AAA MI Rx Correct metabolic abnormality: 0.9% NS + KCl Ix Benign Bloods § Endoscopic balloon dilatation § FBC, U+E, amylase, CRP, G+S, clotting § Pyloroplasty or gastroenterostomy § ABG: ? mesenteric ischaemia Malignant Urine dipstick § Stenting Imaging § Resection § Erect CXR - Must be erect for ~15min first - Air under the diaphragm seen in 70% Hypertrophic Pyloric Stenosis - False +ve in Chailaditi’s sign § AXR Epidemiology - Rigler’s: air on both sides of bowel wall Sex: M>F=4:1 Race: ↑ in Caucasians Mx Presentation Resuscitation 6-8wks NBM Projectile vomiting minutes after feeding Aggressive fluid resuscitation RUQ mass: olive § Urinary Catheter ± CVP line Visible peristalsis Analgesia: morphine 5-10mg/2h max § ± cyclizine Dx Abx: cef and met Test feed: palpate mass + see peristalsis NGT Hypochloraemic hypokalaemic metabolic alkalosis US Conservative May be considered if pt. isn’t peritonitic Mx Careful monitoring, fluids + Abx Resuscitate and correct metabolic abnormality Omentum may seal perforation spontaneously NGT preventing operation in ~50% Ramstedt pyloromyotomy: divide muscularis propria Surgical: Laparotomy DU: abdominal washout + omental patch repair GU: excise ulcer and repair defect Partial / gastrectomy may rarely be required § Send specimen for histo: exclude Ca Test and Treat 90% of perforated PU assoc. c̄ H. pylori 31 © Alasdair Scott, 2018  Gastric Cancer Epidemiology Spread Incidence: 23/100,000 w/i stomach: linitis plastica Age: 50s Direct invasion: pancreas Sex: M>F=2:1 Lymphatic: Virchow’s node Geo: ↑ in Japan, Eastern Europe, China, S. America Blood: liver and lung Transcoelomic Risk Factors § Ovaries: Krukenberg tumour (Signet ring morph) Atrophic gastritis (→ intestinal metaplasia) § Sister Mary Joseph nodule: umbilical mets § Pernicious anaemia / AI gastritis § H. pylori Ix Diet: ↑ nitrates – smoked, pickled, salted (↑ Japan) Bloods § Nitrates → carcinogenic nitrosamines in GIT § FBC: anaemia Smoking § LFTs and clotting Blood group A Imaging Low SEC § CXR: mets Familial: E. cadherin abnormality § USS: liver mets Partial gastrectomy § Gastroscopy + biopsy § Ba meal Staging Pathology § Endoluminal US Mainly adenocarcinomas § CT/MRI Usually located on gastric antrum § Diagnostic laparoscopy H. pylori may → MALToma Mx Classification Medical Palliation Depth of Invasion Analgesia: e.g. fentanyl patch Early gastric Ca: mucosa or submucosa PPI Late gastric Ca: muscularis propria breached Secretion control Chemo: epirubicin, 5FU, cisplatin Microscopic Appearance Palliative care team package Intestinal: bulky, glandular tumours, heaped ulceration Surgical Palliation Diffuse: infiltrative c̄ signet ring cell morphology Pyloric stenting Bypass procedures Borrmann Classification Polypoid / fungating Curative Surgery Excavating EGC may be resected endoscopically Ulcerating and raised Partial or total gastrectomy c̄ roux-en-Y to prevent bile Linitis plastica: leather-bottle like thickening c̄ flat reflux. rugae § Spleen and part of pancreas may be removed Symptoms Prognosis Usually present late Overall: 5ys 50% occur in the stomach. ↑ gastrin c̄ ↑↑ HCl (pH50, surgery is 1 -line Rx Laparoscopic Gastric Banding Inflatable silicone band around proximal stomach → small pre-stomach pouch. § Limits food intake § Slows digestion At 1yr 46% mean excess wt. loss Roux-en-Y Gastric Bypass Oesophagojejunostomy allows bypass of stomach, duodenum and proximal jejunum. Alters secretion of hormones influencing glucose regulation and perception of hunger / satiety. Greater wt. loss and lower reoperation rates. Complications § Dumping syndrome § Wound infection § Hernias § Malabsorption § Diarrhoea 34 © Alasdair Scott, 2018  Hepatobiliary Surgery Contents Gallstones............................................................................................................................................................ 36 Biliary Colic.......................................................................................................................................................... 36 Acute Cholecystitis............................................................................................................................................... 37 Chronic Cholecystitis........................................................................................................................................... 37 Rarer Gallstone Disease...................................................................................................................................... 37 Obstructive Jaundice........................................................................................................................................... 38 Pancreatic Carcinoma.......................................................................................................................................... 38 Acute Pancreatitis................................................................................................................................................ 39 Complications of Acute Pancreatitis.................................................................................................................... 40 Chronic Pancreatitis............................................................................................................................................. 40 Pancreatic Endocrine Neoplasia.......................................................................................................................... 41 Pancreatic Malformations.................................................................................................................................... 41 Cholangiocarcinoma............................................................................................................................................ 42 Hydatid Cyst......................................................................................................................................................... 42 35 © Alasdair Scott, 2018 Gallstones Biliary Colic Epidemiology Pathogenesis ~8% of the population >40yrs Gallbladder spasm against a stone impacted in the neck of Incidence ↑ over last 20yrs: western diet the gallbladder – Hartmann’s Pouch. Slightly ↑ incidence in females Less commonly, the stone may be in the CBD 90% of gallstones remain asymptomatic Presentation Formation Biliary colic § RUQ pain radiating → back (scapular region) General Composition § Assoc. c̄ sweating, pallor, n/v Phospholipids: lecithin § Attacks may be ppted. by fatty food and last 6mm § Female - Inflamed GB: wall oedema § OCP, pregnancy If Dx uncertain after US § ↑ age § HIDA cholescintigraphy: shows failure of GB filling § High fat diet and obesity (requires functioning liver) § Racial: e.g. American Indian tribes If dilated ducts seen on US → MRCP § Loss of terminal ileum (↓ bile salts) Rx Pigment Stones: 5% Conservative Small, black, gritty, fragile § Rehydrate and NBM Calcium bilirubinate § Opioid analgesia: morphine 5-10mg/2h max Associated c̄ haemolysis § High recurrence rate \ surgical Rx favoured Surgical Mixed Stones: 75% § Laparoscopic cholecystectomy Often multiple Cholesterol is the major component Complications In the Gallbladder Biliary Colic Acute cholecystitis ± empyema Chronic cholecytsitis Mucocele Carcinoma Mirizzi’s syndrome In the CBD Obstructive jaundice Pancreatitis Cholangitis In the Gut Gallstone ileus 36 © Alasdair Scott, 2018 Acute Cholecystitis Chronic Cholecystitis Pathogenesis Symptoms: Flatulent Dyspepsia Stone or sludge impaction in Hartmann’s pouch Vague upper abdominal discomfort → chemical and / or bacterial inflammation Distension, bloating 5% are acalculous: sepsis, burns, DM Nausea Flatulence, burping Sequelae Symptoms exacerbated by fatty foods Resolution ± recurrence § CCK release stimulates gallbladder Gangrene and rarely perforation Chronic cholecystitis Differential Empyema PUD IBS Presentation Hiatus hernia Severe RUQ pain Chronic pancreatitis § Continuous § Radiates to right scapula and epigastrium Ix Fever AXR: porcelain gallbladder Vomiting US: stones, fibrotic, shrunken gallbladder MRCP Examination Local peritonism in RUQ Mx Tachycardia c̄ shallow breathing Medical ± jaundice § Bile salts (not very effective) Murphy’s sign Surgical § 2 fingers over the GB and ask pt. to breath in § Elective cholecystectomy § → pain and breath catch. Must be –ve on the § ERCP first if US shows dilated ducts and stones L Phlegmon may be palpable § Mass of adherent omentum and bowel Boas’ sign § Hyperaesthesia below the right scapula Rarer Gallstone Disease Ix Mucocele Urine: bilirubin, urobilinogen Neck of gallbladder blocked by stone but contents remains Bloods sterile § FBC: ↑ WCC Can be very large → palpable mass § U+E: dehydration from vomiting May become infected → empyema § Amylase, LFTs, G+S, clotting, CRP Imaging § AXR: gallstone, porcelain gallbladder § Erect CXR: look for perforation Gallbladder Carcinoma § US Rare - Stones: acoustic shadow Associated c̄ gallstones and gallbladder polyps. - Dilated ducts (>6mm) Calcification of gallbladder → porcelain GB - Inflamed GB: wall oedema Incidental Ca found in 0.5-1% of lap choles. If Dx uncertain after US § HIDA cholescintigraphy: shows failure of GB filling (requires functioning liver) Mirizzi’s Syndrome MRCP if dilated ducts seen on US Rare Large stone in GB presses on the common hepatic duct Mx → obstructive jaundice. Conservative Stone may erode through into the ducts § NBM § Fluid resuscitation § Analgesia: paracetamol, diclofenac, codeine § Abx: cefuroxime and metronidazole Gallstone Ileus § 80-90% settle over 24-48h Large stone (>2.5cm) erodes from GB → duodenum O § Deterioration: perforation, empyema through a cholecysto-duodenal fistula 2 to chonic inflam. Surgical May impact in distal ileum → obstruction § May be elective surgery @ 6-12wks (↓ Rigler’s Triad: inflam) § Pneumobiliia § If 60yrs Ix Painless obstructive jaundice: dark urine, pale stools Urine Epigastric pain: radiates to back, relieved sitting § Dark forward § ↑ bilirubin Anorexia, wt. loss and malabsorption § ↓ urobilinogen Acute pancreatitis Bloods Sudden onset DM in the elderly § FBC: ↑ WCC in cholangitis § U+E: hepatorenal syndrome § LFT: ↑cBR, ↑↑ ALP, ↑AST/ALT Signs § Clotting: ↓ vit K → ↑ INR