POST-OPERATIVE COMPLICATIONS AND

MANAGEMENT

Postoperative complications may either be general or specific to the type of surgery

undertaken and should be managed with the patient's history in mind.

General Complications

• Fever•Hemorrhage •Wound infection•Wound dehiscence• Pressure sores•Drains copmlications• Complications of blood transfusions

Fever

• 40% of patients develop pyrexia after major surgery.• 80% of cases no particular cause is found.• Pyrexia does not necessarily imply sepsis.• The inflammatory response to surgical trauma may

manifest as temperature. In spite of this, a focus of infection must always be sought if a patient develops anything more than a slight pyrexia.

The causes of raised temperature postoperatively include:

• days 2–5: atelectasis of the lung;• days 3–5: superficial and deep wound infection;• day 5: chest infection including viral respiratory tract infection, urinary tract infection and thrombophlebitis;• >5 days: wound infection, anastomotic leakage, intracavitary collections and abscesses;• infected intravenous cannula sites, DVTs, transfusion reactions, wound haematomas, atelectasis and drug reactions, which may also cause pyrexia of non-infective origin.

Patients with persistent pyrexia need a thorough review. Relevantinvestigations include: full blood count, urine culture if urinary tract infection is suspected, sputum microscopy, chest radiography, and blood cultures.

Hemorrhage• The hemorrhage may occur immediately after the

surgery or be delayed. It need not be restricted to the surgical wound. Common causes of postoperative hemorrhage are from tissues which cannot be entirely prevented from bleeding and depend on blood clotting to stop the hemorrhage, so haemorrhage may be exacerbated by consumption coagulopathy. It may also be due to preoperative anticoagulants or unrecognised bleeding diathesis.

• Perform clotting screen and platelet count, ensure good intravenous (IV) access. If there is very significant bleeding and it is safe to do so, consider inserting a central venous pressure (CVP) catheter. Give protamine if heparin has been used. Order cross-matched blood. If the clotting screen is abnormal, give fresh frozen plasma (FFP) or platelet concentrates. Consider surgical re-exploration at all times.

• Late postoperative haemorrhage occurs several days after surgery and is usually due to infection damaging vessels at the operation site. Treat the infection and consider exploratory surgery

Wound InfectionDefined as invasion of organisms through tissues following breakdown of local and systemic host defenses.Usually referred to as Superficial Surgical Site Infection (SSSI)Should be presented within 30 days of surgery;occur usually after the third day , with involvement of skin and subcutaneous tissues Clinically presented with serosanguinous or purulent discharge pain ,tenderness, localized swelling, redness, hotness.

Predisposing factors for wound infection

General Factors: • Age (elderly).

• Diabetes mellitus.

• Malignant disease.

• Immunesuppression (AIDS,Steroid)

Local factors• Necrotic tissue.

• Foreign bodies.

• Hematoma formation.

• Poor surgical technique.

• Wound infections are classified as :

Minor

( purlent material around skin suture sites)

Major

( discrete collection of pus within the wound )

• Wound infection rate varies with the type of surgery : I clean : no viscus opened 1-2 % infection rate

II clean-contaminated : viscus opened but with no spillage of content

8-10 % infection rate

III contaminated: viscus opened with content spillage 15-20 % inf.rate

IV dirty (infected) :intraperitoneal abcess or visceral perforation 40 %

Management :

• Incision should be opened for drainage

• Debridement if there is necrosis

• Antibiotics

Prevention :

1. Skin preparation

2. Bowel preparation

3. Prophylactic antibiotic

4. Meticulous technique

5. Appropriate drainage

Wound Dehiscence• This is the partial or complete disruption of any or all of the

layers in a wound.• If it occurs in the abdomen it may be very distressing to

the patient, causing extrusion of the bowel and other organs.• Dehiscence may occur in up to 3% of abdominal wounds.• Wound dehiscence most commonly occurs from the fifth to

the eight postoperative day when the strength of the wound is at its weakest.• It most commonly occurs in abdominal wounds where it

may herald an underlying intra-abdominal abscess.

Risk factors in wound dehiscence• General■ Malnourishment■ Diabetes■ Obesity■ Renal failure■ Jaundice■ Sepsis■ Cancer■ Patients on steroids• Local■ Inadequate or poor closure of wound■ Poor local wound healing, e.g. because of infection, haematoma or seroma■ Increased intra-abdominal pressure, e.g. in postoperativepatients suffering from chronic obstructive airway disease, during excessive coughing.

• Wound dehiscence usually presents with a serosanguinous discharge.• The patient may have felt a popping sensation during

straining or coughing.

Most patients will need to return to the operating theatre for resuturing. In some patients it may be appropriate to leave the wound open and treat with dressings or vacuum-assisted closure (VAC) pumps.

Pressure Sores• These occur as a result of friction or persisting pressure on soft

tissues.

• They particularly affect the pressure points of a recumbent patient, including the sacrum, greater trochanter and heels.

• Risk factors are poor nutritional status, dehydration and lack of mobility.

• Those who are unconscious or who are unable to turn in bed should have their position in bed changed every 30 min to prevent pressure sores.

• High-risk patients may be nursed on an air

• filter mattress, which automatically alters the pressure areas.

• High-risk patients may be nursed on an air filter mattress, which automatically alters the pressure areas.

• Early mobilisation prevents pressure sores.

The complications associated with abdominal drains include:

• trauma during insertion;• failure to drain because of incorrect placement or blockage;• complications caused by disconnection;• sepsis at drain sites;• drain site metastases;• erosion by the drain of adjacent tissue and perforation ofabdominal viscera.

Drains should be removed once the drainage has stopped orbecome less than 25 ml day−1, as they are a potential track forcontamination and infection into a wound

Complications of blood transfusion

• Major/minor ABO incompatibility causes tachycardia, pyrexia, rash and pruritus in minor cases, and flushing, urticaria bronchospasm and hypotension in severe reactions. • The transfusion should be stopped at once if the patient develops

these symptoms.• A sample of the blood from the donor and recipient should be sent for culture and the remainder of the blood in the bag sent back to the transfusion department for recross-matching. • In severe reactions, steroids and anti-histamines may be required.

SPECIFIC POSTOPERATIVE COMPLICATIONS

Respiratory complications: Respiratory complications occur after major surgery, particularly after general anaesthesia and can include :• Atelectasis (alveolar collapse):• This is caused when airways become obstructed, usually by

bronchial secretions. Most cases are mild and may go unnoticed.• Symptoms are slow recovery from operations, poor colour,

mild tachypnoea and tachycardia and post-operative fever.• Prevention is by preoperative and postoperative

physiotherapy.• In severe cases, positive pressure ventilation may be

required.

• Aspiration pneumonitis:• Up to 4.5% has been reported in adults; higher in children.• Sterile inflammation of the lungs from inhaling gastric

contents.• Presents with a history of vomiting or regurgitation with

rapid onset of breathlessness and wheezing. • A non-starved patient undergoing emergency surgery is

particularly at risk.• It may be of help to avoid this by crash induction technique

and use of oral antacids or metoclopramide.• Mortality is nearly 50% and requires urgent treatment with

bronchial suction, positive pressure ventilation, prophylactic antibiotics and IV steroids.

Cardiovascular complications:Hypotension:• The commonest cause of low blood pressure

postoperatively is hypovolaemia, as a result of either bleeding or insufficient fluid replacement.• Also an overdose of analgesia (e.g. opioids) and epidural

anaesthesia may be complicated by hypotension because of the vasodilatation of veins. Septic shock may also present In this way.• Whatever the cause of hypotension, the emergency

treatment requires an increase in the fluid input with administration of high-flow oxygen. The patient should also be tilted head-down to maintain cerebral perfusion. A thorough examination should then be performed to determine the cause of the collapse.

HypertensionHigh blood pressure may be dangerous in patients with ischaemic heart disease or cerebrovascular disease as it may precipitate infarction or stroke. Most causes of hypertension relate to inadequate pain relief or anxiety and usually settle with appropriate analgesia.

Thromboembolism• DVT and pulmonary embolism  are major causes of complications and death

after surgery.Risk factors for DVT

■ Age > 60 years

■ Recent surgery, particularly pelvic and lower limb surgery

■ Immobilisation

■ Trauma

■ Oral contraceptive pill

■ Obesity

■ Heart failure

■ Cancer

■ Arteriopathy

• In DVT Many cases are silent but present as swelling of the leg, tenderness of the calf muscle and increased warmth with calf pain on passive dorsiflexion of the foot.• Diagnosis is by venography or Doppler ultrasound.• Pulmonary embolism:Classically presents with sudden

dyspnoea and cardiovascular collapse with pleuritic chest pain, pleural rub and haemoptysis. • treatment with intravenous heparin initially, followed by

longer-term warfarin, should be started immediately.• Prevention of DVT■ Early mobilisation■ Hydration■ Compression stockings■ Low molecular weight heparin as prophylaxis■ Calf pumps■ Minimise use of tourniquets

Gastrointestinal complicationsPostoperative nausea and vomitingThis is a common problem and results in patient weakness anddemoralisation. It may have an adverse effect on the outcome ofsurgery including wound dehiscence and pulmonary aspiration ifthe patient’s airway is unprotected. Prolonged nausea and vomitingresults in increased pain levels and a prolonged hospital stay.Predisposing factors :• poorly controlled pain;• use of opioids;• surgery on the gastrointestinal tract, orthopaedic surgery or ENT surgery;• female sex;• young adult;• history of preoperative vomiting;• history of motion sickness or migraine;• acute gastric dilatation.

Treatment of postoperative nausea and vomiting

General measures Adequate pain control Avoid opiates Keep stomach empty by aspirating (consider nasogastric tubes) Start oral feeding slowly Maintain hydration and blood pressure Epidural analgesia

Drugs Dopamine receptor antagonists, e.g. prochlorperazine Metoclopramide H1 receptor antagonists, e.g. cyclizine 5HT receptor antagonists, e.g. ondansetron

Paralytic ileus

• Following laparotomy, gastrointestinal motility temporarily decreases.• Paralytic ileus may present with nausea, vomiting,

refusal to eat, bowel distension and absence of flatus or bowel movements.• Abdominal radiography reveals a dilated bowel.• Treatment is usually supportive with maintenance of

adequate hydration and electrolyte levels.• The return of function of the intestine occurs in the

following order: small bowel, large bowel, stomach.

Urinary complicationsUrine output (oliguria/anuria)

• The commonest cause of oliguria postoperatively is reduced renal perfusion resulting from perioperative hypotension or inadequate fluid replacement.

• If untreated, acute renal failure may develop.

• To ensure that fluid management is adequate, daily input/output charting should be maintained. The urine output should be measured on an hourly basis after major surgery to detect early changes in renal function.

• Monitor renal function: Serum urea, creatinine and electrolytes, Urine output monitoring

• Assess volume status: Pulse and blood pressure ,Serial body weight ,Central venous pressure Pulmonary capillary wedge pressure

• Optimise cardiac function Monitor cardiac output Consider inotropic support

• Relieve urinary obstruction Prompt diagnosis Catheter drainage Surgical correction

• Avoid nephrotoxins: Limit toxins Avoid aminoglycosides Adjust drug doses

• Prevent sepsis :Catheter care Drain abscesses Give antibiotics

• Consider diuretics :Mannitol and frusemide (furosemide)

Urinary retention• This is frequently seen in postoperative patients,

particularly men who are bed-bound postoperatively. The inability to void after surgery is particularly common with pelvic and perineal operations or after procedures performed under spinal anaesthesia.• The causes of retention are related to the interference of

neural mechanisms that are usually responsible for normal bladder emptying and over-distension of the bladder• Retention may be confirmed by ultrasound and may require catheterisation.• Catheterisation should be performed prophylactically when

an operation is expected to last 3 hours or longer or when large volumes of fluid are administered.

Urinary infection• This is the one of the most commonly acquired infections in

thepostoperative period.• Urinary tract infections should always be considered in the

differential diagnosis of a patient with fever postoperatively.• Patients who are immunocompromised or diabetic, or who have

pre-existing urinary tract contamination, urinary retention or a history or presence of catheterisation, are known to be at higher risk.• Symptoms of urinary tract infection and cystitis include dysuria

and mild pyrexia; however, pyelonephritis may cause severe flank tenderness in addition to high temperatures.• The diagnosis is confirmed by dipsticking the urine and sending

samples for culture and sensitivity.• Treatment involves adequate hydration and proper bladder

drainage together with the use of relevant antibiotics.