Post-operative complications may be either general or specific to a particular operation that was carried out. We can also classify it as immediate (<24 hours), early (days - weeks), or late (months - years).
Some examples of immediate and early complications are:
Immediate complications
- Haemorrhage
- Shock
- Hypovolaemia
- Oliguria
- Structural damage
We will discuss some of these in more detail…
Assessing the post-operative patient
ABCDE approach is necessary to assess the patient generally.
However, we can also consider other factors such as the risk factors for the patient, their PMH, DH, wounds, drains, lines, catheters, fluid balance.
Let’s discuss post-op fluid balance a little further:
Early
- Pain
- PONV
- Delirium
- Fever
- Pneumonia
- Wound dehiscence/anastomotic leak
- Urinary retention
- VTE
- Wound infection
- Pressure sores
- Paralytic ileus
- Haemorrhage
Post-operative fluid management
Na | K | Cl | Bicarbonate | Lactate | |
Plasma | 137-147 | 4-5.5 | 95-105 | 22-25 | - |
0.9% Saline | 153 | - | 153 | - | - |
Dextrose / saline | 30.6 | - | 30.6 | - | - |
Hartmans | 130 | 4 | 110 | - | 28 |
These are the compositions for some commonly administered IV fluids…
In the past, patients were given excessive IV fluids such as normal saline post-operatively without consideration thus leading to → hyperchloraemic acidosis. Now more balanced solutions such as Hartmans solution are favoured.
5% dextrose and dextrose/saline combos are not recommended for surgical patients either.
- Fluid status should be assessed after leaving theatre
- Euvolaemic and haemodynamically stable patients should be encouraged to start oral fluid intake ASAP
- If urinary sodium is <20, the patient needs reviewing
- Dextran 70 should be used in caution in sepsis patients as they may develop AKI.
There are 3 types of operative haemorrhages:
- Primary haemorrhage - intraoperatively.
- Reactive haemorrhage - <24 hours.
- Secondary haemorrhage - within 7-10 days.
Haemorrhage may lead to hypovolaemic shock of course. Let’s discuss the 4 grades of hypovolaemic shock (we will look into this further in the “shock” CCP).
😷 Presentation
- Tachycardia
- Tachypnoea
- Cold peripheries
- CRT >2s
- Hypotension (late sign)
- Delirium
- Reduced urine output
- Swelling/tenderness/bruising of surgical site
→ If a patient has a Hb <100g/l oral iron should be started (200mg ferrous sulphate 3x daily for 3 months)
→ If the Hb is <70-80g/l then there should be a blood transfusion + oral iron.
Occurs in about 1/4 surgical patients.
The issue with PONV is that it may cause a stress response, delay recovery, cause wound dehiscence, lead to hypokalaemia, increases pain.
⚠️ Risk factors
- Female
- Young
- Previous PONV
- Motion sickness
- Opioids
🔮 Prophylaxis
Reduction of intra-operative opiates and volatile gases.
Prophylactic antiemetics and dexamethasone.
🧰 Management
- Analgesia and hydration
- Exclusion of other causes
- Anti-emetic treatment (metoclopramide, domperidone, ondansetron, cyclizine)
- 🥇 5HT3 receptor antagonist e.g. Ondansetron - first line. Risk of QT prolongation and constipation
- Histamine (H1) receptor antagonist e.g. Cyclizine. Avoid in severe heart failure
- Dopamine (D2) receptor antagonist e.g. Prochlorperazine. Risk of extrapyramidal side effects (dystonic reactions)
- Be careful of using metoclopramide. Although it is a very good anti-emetic there is a risk of acute dystonic reaction, clasically in patients younger than 30 years old and when doses of greater than 30 mg per day are administered.
Acute fluctuation in consciousness, attention, cognition and perception.
⚠️ Risk factors
- Dehydration
- Pain
- Hypoxia
- Infection
- Medication
- Urinary retention
We can assess delirium using The Confusion Assessment Method (CAM).
🧰 Management
One must look for the cause of the delirium and rectify this.
Medications should be reviewed.
MDT input would be necessary.
Haloperidol or lorazepam should be used as a last resort and avoided if possible.
Surgery can cause low-grade pyrexia, however, infection is common post-operatively and this may present with pyrexia as well.
⚠️ Causes
- Wound infection
- Abscesses (pelvic/subphrenic abscesses)
- Pneumonia/PE in chest
- Phlebitis with cannula
- Infection of central line
- UTI from catheter
- DVT in calves
🧰 Management
Sepsis six is always a good assessment along with ABCDE
Search for the causative factor, this can be done using a “septic screen”:
- CXR for pneumonia
- Urine culture for UTI
- Wound swab for infection (check under surgical dressings!)
- Blood cultures for bacteraemia
- CT looking for an anastomotic leak (collection of fluid)
Empirical antibiotics are also recommended depending on the suspected agent
Microbiology + surgical involvement is necessary.
Almost 60% of patients have post-operative pain.
It is an issue as delays recovery and mobilisation (increasing risk of DVT), there is almost always some dehr
🧰 Management
The WHO analgesic ladder is always useful to follow.:
- Step 1: Non-opioid ± adjuvant
- Step 2: weak opioid ± non-opioid ± adjuvant
- Step 3: stronger opioid ± non-opioid ± adjuvant
Analgesia should be prescribed regularly.
Patient controlled analgesia (PCA) may also be offered through IV blouses.
Following laparotomy, one may implement a rectus sheath catheter for example. ↗️
Anaesthetics and the acute pain team are often involved.
As mentioned atelectasis is a common in surgical patients. This allows for fluid secretions and hypoventilation.
⚠️ Risk factors
- Increasing age
- Smoking
- Obesity
- Poor mobility postoperatively (e.g. due to PONV or pain)
- Ventilator usage (VAP)
- Co-morbidities/immunosuppressants
🧰 Management
Confirmed pneumonia should be treated with empirical antibiotics, pending sensitivities. Antibiotic choice should be guided by local policy; an example regimen is:
- Mild: Co-amoxiclav 625mg oral TDS
- Moderate: Co-amoxiclav 625mg oral TDS
- Severe: Tazocin 4.5g TDS IV
All surgical patients require VTE risk assessment to see if they may need thromboprophylaxis.
🔮 Thromboprophylaxis
- Pharmacological thromboprophylaxis - LMWH
- Mechanical thromboprophylaxis - TED stockings (thromboembolism deterrent stockings) or pneumatic compression
Mobilisation of the patient early on along with hydration is also important.
🔍 Investigations
A Wells score can be calculated in patients with potential DVT:
A score >2 is likely of DVT while a score of <1 is unlikely.
- If likely of DVT → perform a lower limb Doppler US.
- If unlikely of DVT → do a D-dimer:
- If positive → perform a lower limb Doppler US.
- If negative → consider alternative.
🧰 Management
🥇 DOAC (direct oral anticoagulants) - such as apixaban or rivaroxaban.
🥈 Warfarin + LMWH bridging (INR target 2-3)
Ensure the GP is informed on discharge.
This is when there is a leak in luminal contents after surgical joining of 2 hollow viscera. It can lead to fatal sepsis and multi-organ failure.
⚠️ Risk factors
- Increasing age
- Smoking
- Obesity
- Alcohol
- Ventilator usage (VAP)
- Steroids/immunosuppressants
- Emergency procedures
😷 Presentation
- Post-operative pyrexia
- Abdominal pain
- Tachycardia
- Delirium
- Raised inflammatory markers
- Prolonged ileus
🧰 Management
- Senior advice
- ABCDE/resuscItation
- NBM
- CT imaging
- Laparotomy/conservative surgery is curative
Please refer to the page on intestinal obstruction/paralytic ileus for more information.