Surgery 2

Question 1

Post-operative Complications

Answer 1

Divide each category into immediate, early and late:

• General post-op complications – anaesthetic complications, wound infection, haemorrhage, neurovascular damage, DVT.
• Specific post-op complications – e.g. saphenous nerve damage in stripping long varicose veins.

Question 2

Haemorrhage

Answer 2

• Primary haemorrhage – continuous bleeding that started during surgery. Replace blood loss and if severe return to theatre for adequate haemostasis. Treat hypovolaemic shock vigorously.
• Reactive haemorrhage – haemostasis appeared secure until blood pressure increased and bleeding occurred. Replace the blood that has been lost and re-explore the wound.
• Secondary haemorrhage – occurs 1-2 weeks post-operatively and usually caused by infection.

Question 3

Pyrexia

Answer 3

Mild pyrexia in the 1st 24 hours is often from atelectasis (collapse of part of the lung) which requires prompt physiotherapy not antibiotics, tissue damage or necrosis or from blood transfusions.

You should have a low threshold for an infection screen – check for signs of wound or cannula site infections, meningism, endocarditis, pneumonia, peritonism, UTIs and DVTs.

Also do bloods for FBC, Us and Es, CRP and cultures, dipstick the urine and consider doing MSU, CXR and abdominal US or CT.

Question 4

Confusion

Answer 4

May manifest as agitation, disorientation and attempts to leave the hospital especially at night.

Common causes – hypoxia (due to pneumonia, atelectasis, LVF or PE), drugs (opiates, sedatives and many others) or urinary retention.

Do bloods – FBC, Us and Es, CRP, LFTs, glucose and septic screen – urine dipstick, chest x-ray and blood cultures. Also consider ECG, malaria films, LP, EEG and CT/MRI.

If sedation is necessary to examine the patient consider giving midazolam or haloperidol. Reassure that post-op confusion is common (occurs in 40%) and reversible.

Question 5

Dyspnoea or Hypoxia

Answer 5

Is there any previous lung disease?

Sit the patient up, give oxygen, connect to a monitor and examine for evidence of pneumonia, lobar collapse, left ventricular failure (MI or fluid overload), pulmonary embolism, pneumothorax (due to CVP line or mechanical ventilation).

Do some investigations e.g. bloods for FBC, CRP, ABG, chest x-ray and ECG and manage according to findings.

Question 6

Hypotension

Answer 6

If severe tilt the bed head down and give oxygen. Check the pulse and blood pressure again and compare with pre-operative levels.

It is caused by hypovolaemia usually from inadequate fluid input (so check the fluid chart and replace losses) but it can also be caused by haemorrhage (so check wounds and the abdomen).

If the patient is unstable return them to theatre for haemostasis.

Question 7

Hypertension

Answer 7

May be caused by pain, urinary retention, idiopathic (missed medication) or inotropic drugs.

Oral cardiac medication including antihypertensives should be continued throughout the perioperative period even when nil by mouth.

Treat the cause, consider increasing the dose of the patient’s regular medication or if not being absorbed orally try 50mg IV Labetalol over 1 minute.

Question 8

Oliguria

Answer 8

Aim for an output of >30mL/hour in adults.

Anuria is usually caused by a blocked or wrongly sited catheter rather than acute renal failure so flush and replace the catheter.

Oliguria is usually caused by inadequate fluid replacement so treat by increasing fluid input.

Also consider acute renal failure – it can follow shock, nephrotoxic drugs, blood transfusion, pancreatitis or trauma.

Question 9

Nausea and Vomiting

Answer 9

Causes include obstruction, ileus or emetic drugs e.g. opiates, digoxin or anaesthetics.

Consider an abdominal x-ray, NG tube and an antiemetic (not metoclopramide as prokinetic).

Question 10

Hyponatraemia

Answer 10

Compare the most recent level to the pre-operative levels.

SIADH can be caused by perioperative pain, nausea, opioids, pneumonia or over administration of IV fluids.

Question 11

Laparotomy

Answer 11

Wound dehiscence occurs in 3.5% - most commonly in the elderly or malnourished, if the patient is already compromised e.g. by malignancy or if this is a 2nd laparotomy.

The warning sign of wound dehiscence is a pink serous discharge. If severe it may lead to a ‘burst abdomen’ with evisceration of bowel – mortality is 15-30%.

If this occurs put the bowel back in to the abdomen, place a sterile dressing over the wound, give IV antibiotics e.g. cefuroxime or metronidazole and call a senior.

A less severe complication is an incisional hernia which can be repaired by mesh insertion.

Question 12

Biliary Surgery

Answer 12

Biliary surgery – CBD damage or stricture, cholangitis, bleeding into the biliary tree (haemobilia) which may lead to biliary colic, jaundice and haematemesis. Other complications include pancreatitis or leakage of bile causing biliary peritonitis.

Laparoscopic cholecystectomy – there is 5% chance of being converted to an open procedure, CBD injury, bile leak, post-operative haemorrhage, intra-abdominal abscess and mortality rate is 0.04%.

Question 13

Thyroid Surgery

Answer 13

Recurrent ± superior laryngeal nerve palsy occurs permanently in 0.5% and transiently in 1.5% - warn the patient that their voice will be different for a few days after surgery due to intubation and local oedema.

In addition hypoparathyroidism causing hypocalcaemia (permanent in 2.5%), hypothyroidism, thyroid storm and tracheal obstruction due to haematoma in the wound may occur (relieve by immediate removal of stitched or clips using a cutter or a remover).

Question 14

Mastectomy

Answer 14

Arm lymphoedema in 20% of those undergoing axillary node sampling or dissection.

Question 15

Arterial Surgery

Answer 15

Bleeding, thrombosis, embolism, graft infection, MI or AV fistula formation.

Complications of aortic surgery – gut ischaemia, renal failure, respiratory distress, aorto-enteric fistula, trauma to ureters or anterior spinal artery or ischaemic events from dislodged thrombosis.

Question 16

Small Bowel or Colon Surgery

Answer 16

• Small bowel surgery – short gut syndrome occurs if the bowel is <250cm (in adults). Diarrhoea and malabsorption (particularly of fats) lead to a number of metabolic abnormalities including deficiencies in vitamins A, D, E, K and B12, hyperoxaluria (causing renal stones) and bile salt depletion (gallstones).
• Colonic surgery – sepsis, ileus, fistulae, anastomotic leak (occurs in 10% of patients after anterior resection), obstruction from adhesions, haemorrhage, trauma to the ureters or the spleen.

Question 17

Tracheostomy

Answer 17

Complications include stenosis, mediastinitis or surgical emphysema.

Question 18

Splenectomy

Answer 18

Acute gastric dilation (serious complication of not using an NG tube or to check that the one is place is functioning), thrombocytosis or sepsis. The lifetime risk is partly preventable with pre-operative vaccines e.g. Haemophilus type B, meningococcal, pneumococcal and prophylactic penicillin.

Question 19

Genitourinary Surgery

Answer 19

Septicaemia (from instrumentation in presence of infected urine so give a stat gentamicin) or urinoma (rupture of the ureter or renal pelvis leads to a mass of extravasated urine).

Question 20

Stoma - Definition

Answer 20

An artificial union between 2 conduits or between a conduit and the outside e.g. a colostomy.

Urostomies – bring urine from ureters to abdominal wall via an ileal conduit following cystectomy.

Question 21

Stoma - Complications

Answer 21

• Early – haemorrhage at stoma site, stoma ischaemia (the colour progresses from dusky grey to black), high output (can lead to hypokalaemia – consider giving loperamide ± codeine to thicken stoma output), obstruction secondary to adhesions or stoma retraction.
• Delayed – obstruction, dermatitis around the stoma site (worse with an ileostomy), stoma prolapse or intussusception, stenosis, parastomal hernia, fistulae or psychological problems.

Question 22

DM - Stopping Insulin and Monitoring

Answer 22

Stress or concurrent illness increases basal insulin needs. Always try to put the patient first on the list and inform the anaesthetist and surgeon early.

• Stopping insulin – stop all long acting insulin the night before. Stop short acting insulin the night before if surgery is in the morning or after breakfast if surgery is in the afternoon. It may be feasible to continue glargine as baseline therapy throughout the perioperative period.
• Monitoring – check the blood glucose hourly and aim for 7-11mmol/L during surgery.

Question 23

DM - Peri and Post-operatively

Answer 23

• Peri-operatively – start an IV infusion of 1L 5% dextrose with 20mmol KCl TDS and start an infusion pump with short acting insulin e.g. Actrapid in 50mL 0.9% saline and give according to a sliding scale adjusted in light of the patient’s blood glucose results.
• Post-operatively – continue IV insulin and dextrose until the patient is tolerating food then switch to the usual subcutaneous regime. Also continue to check venous glucose every 2 hours.

Question 24

DM - Minor Surgery

Answer 24

If the patient is going to be nil by mouth <6 hours and will definitely be able to eat after the operation then IV insulin may not be necessary.

Some advocate a small glucose drink before surgery and delaying morning insulin and breakfast until after the procedure.

Question 25

Type 2 DM

Answer 25

If diabetes is ***poorly controlled*** e.g. the blood glucose is \>10mmol/L treat ***as for type 1 diabetes*** (above). ***Do not give long acting*** sulphonylureas on the morning of surgery as these can cause ***prolonged hypoglycaemia*** on fasting. If the patient will be ***able to eat post-operatively*** simply omit tablets on the morning of surgery and ***give post-operatively*** with a meal. If the patient is have ***major surgery*** with restrictions on eating post-op check fasting glucose on the morning of surgery and ***start IV or SC insulin on a sliding scale.***

Question 26

Jaundice and Surgery

Answer 26

Surgery is ***best avoided*** in patients with obstructive jaundice as they are ***prone to developing renal failure*** after surgery, perhaps from the ***toxic effects of bilirubin*** and any ***concomitant sepsis***. In practice this means that a ***good renal output*** must be maintained in such patients around the time of surgery.

Question 27

Jaundice - Pre-Operatively

Answer 27

Avoid morphine, give prophylactic ***antibiotics*** to prevent sepsis, give 1L IV ***0.9% saline*** to produce a moderate ***diuresis*** peri-operatively but if this is not effective a loop diuretic e.g. ***furosemide*** may be required. Check clotting and consider giving ***prophylactic vitamin K*** even if normal.

Question 28

Jaundice - Peri and Post-Operatively

Answer 28

* ***During surgery*** – measure urine output hourly and give 0.9% IV saline to match output. * ***48 hours post-operatively*** – measure urine output every 2 hours and Us and Es daily to ***identify renal failure***. Give 0.9% saline at a rate to match urine output and fluid lost e.g. through an NG tube. ***Consider furosemide*** and a ***central line*** if urine output is poor despite adequate hydration.

Question 29

Surgery and Steroids

Answer 29

Patients need ***extra cover to cope with stress*** of surgery as there endogenous adrenal ***hormone levels will be suppressed*** even for a period after cessation of a course of treatment. The amount of extra cover required depends on the type of surgery and the pre-operative dose of steroids. * ***For major surgery*** – give 50-100mg IV Hydrocortisone with pre-med - then every 6-8 hours for 3 days. * ***For minor surgery*** – prepare as the major surgery except that hydrocortisone is only given for 24 hours. * ***The main risk*** of adrenal insufficiency is ***hypotension*** so if this occurs give stat Hydrocortisone.

Question 30

Surgery and Anticoagulants

Answer 30

* ***Minor surgery*** – in some cases can be performed on warfarin – check the INR is \<3.5 within 24 hours. * ***Major surgery*** – usually warfarin is stopped 2-5 days pre-operatively however risks and benefits need to be adjusted for each patient. ***Vitamin K and FFP*** may be required for emergency surgery. * ***Conversion to unfractionated heparin*** is an option as it has a ***short half-life*** and can be rapidly reversed using ***protamine***. When re-warfarinising do not stop heparin ***until the INR is therapeutic*** as warfarin is ***pro-thrombotic*** in the early stages.