Postoperative Complications Flashcards
Timeframe for immediate complications
Within 24 hours of surgery
Timeframe for early complications
Occur within 30 days of the operation or during the period of hospital stay
Timeframe of late complications
Occur after the patient has been discharged from hospital or more than 30 days from the operation
Define primary haemorrhage
- Occurs during the operation
- Should be controlled during the operation
Define reactionary haemorrhage
- Occurs within the first few hours of surgery
- e.g. due to clot disturbance with rise in BP
Define secondary haemorrhage
- Occurs a number of days after the operation
- Usually infection related but can also be due to sloughing of a clot or erosion of ligature
List the predisposing factors for haemorrhage
- Obesity
- Steroid therapy
- Jaundice
- Recent transfusion of stored blood
- Disorders of coagulation
- Platelet deficiencies
- Anticoagulation
- Old age
- Severe sepsis/DIC
Causes of pyrexia 1-3 days post-op
- Atelectasis
- Metabolic response to trauma
- Drug rections
- SIRS
- Line infection
- Instrumentation of a viscus or tract causing transient bacteraemia
Causes of pyrexia 4-6 days post-op
- Chest infection
- Superficial wound infection
- Urinary infection
- Line infection
Causes of pyrexia beyond 7 days post-op
- Chest infection
- Suppurative wound infection
- Anastomotic leak
- Deep abscess
- DVT
How can abdominal wound dehiscence be divided
- Superficial = skin wound alone fails
- Complete = failure of all layers
What factors increase the risk of wound dehiscence
- Malnutrition
- Vitamin deficiencies
- Jaundice
- Steroid use
- Major wound contamination
- Poor surgical technique (i.e. not abiding by Jenkins rule)
Management of complete wound dehiscence
- Analgesia
- IVF
- IV antibiotics
- Coverage of the wound with saline impregnated gauze
- Arrange to return to theatre
When may a dehisced wound be re-sutured
- Wound edges are healthy
- Enough tissue for suitable coverage
- Deep tension sutures are used
What method of re-closure should be used if the dehisced wound has some granulation tissue present over the viscera of there is high output bowel fistula present
Wound manager
Anaesthetic contributions to post-op respiratory problems
- Reduced residual capacity from supine positions
- V/Q mismatch: increased shunt or dead space
- One-lung ventilation
- Excessive sedation
- Muscle relaxants
- Impaired host defences
What are the nutritional requirements of those with renal failure
- High calorie
- High-quality protein
List the indications for renal replacement therapy
- Hyperkalaemia (persistently >6)
- Metabolic acidosis (pH<7.2) with negative base excess
- Pulmonary oedema/overload
- High urea (30-40)
- Complications of uraemia e.g. pericarditis, tamponade
- Creatinine rising >100/day
- The need to ‘make room’ for ongoing drug infusions
SIRS criteria
Two or more of:
- Tachycardia >90
- Respiratory rate >20 or PaCO2 >4.3
- Temp >38 or <36
- WCC >12 or <4
Insults that may result in SIRS
- Infection and sepsis
- Ischaemia-reperfusion syndrome
- Fulminant liver failure
- Pancreatitis
- Dead tissue
Harmful effects of oxygen free radicals
Direct endothelial damage and increased permeability
Role of macrophages in SIRS
- Phagocytosis of debris and bacteria
- Act as antigen-presenting cells for T-lymphocytes
- Release inflammatory mediators, endothelial cells and fibroblasts
Describe the ‘two-hit’ hypothesis
- Initial cellular insult e.g. trauma or shock sets up a controlled inflammatory response
- A second insult is then sustained by the patient e.g. from surgery which creates a destructive inflammatory response
This can cause loss of intestinal mucosal integrity and allows the translocation of bacteria into the portal circulation
Mortality rate in two organ failure
50% (increasing to 66% by day 4)
Mortality rate in three organ failure
80% (rising to 96%)
Criteria for GI failure
- Ileus >3 days
- Diarrhoea >4 days
- GI bleeding
- Inability to tolerate enteral feed in absence of primary gut pathology
Criteria for skin failure
Decubitus ulcers
Criteria for cardiac failure
- HR <54 or symptomatic bradycardia
- MAP <49
- VF or VT
- Serum pH <7.24 with normal pCO2
Criteria for respiratory failure
- RR <5 or >49
- PaCO2 >6.65
- Alveolar-arterial gradient >46.5
- Ventilator-dependent on day 4 in ITU
Criteria for renal failure
- Urine output <479ml in 24 hours
- Urea >36
- Creatinine >310
- Dependent on haemofiltration
Criterial for haematological failure
- WCC <1
- Platelets <20
- Haematocrit <0.2
- DIC
Criteria for neurological failure
- GCS <6 in absence of sedation
qSOFA criteria
RR >22
GCS <15
SBP <100
When is MI most likely post-op
Day 1
