Perioperative Complications

Question 1

Perioperative medications to stop

Answer 1

-ACE inhibitors (morning of surgery due to risk of AKI)
-COCP (4 weeks prior to surgery due to VTE risk)

-Apixaban should be stopped at least 24 hours prior to interventions with a low risk of bleeding
-Apixaban should be discontinued at least 48 hours prior to elective surgery or invasive procedures with a moderate or high risk of bleeding
-If thromboprophylaxis is indicated, LMWH should be commenced at prophylactic doses, and the first dose given at least 24 hours after the last dose of apixaban
-If it is an emergency situation and you can’t wait, regional anaesthesia is contra-indicated (haematoma in spine)
-Once post-operative haemostasis is secure, apixaban can be restarted 24 hours after the last dose of LMWH

-Stop warfarin if low thrombosis risk (omit 5 doses prior to theatre) no pre-op LMWH required
-Stop if high risk (enoxaparin day 3, 2, 1)

-Diabetic mediation withheld or altered according to local protocol (variable rate insulin infusion)

Question 2

Perioperative medications that can continue

Answer 2

-Aspirin (low dose)
-Beta blockers

Question 3

Complications in the immediate post-operative period

Answer 3

-Pain
-Inadequate analagesia
-Haematoma
-Nerve irritation (neurostenalgia)
-Compartment syndrome

Question 4

Complications in the 3 days post-operative period

Answer 4

-Infection
=Cellulitis
=Metalwork / implant infection
=Abscess
-Metalwork failure

Question 5

Review of pain management in post-operative pain

Answer 5

1. Anaesthetic methods of post-operative analgesia, such as a regional block or a epidural.* When was it sited? Is it still working?
2. Surgical methods of post-operative analgesia, such as elevation, orthoses, and casts* Are they being correctly implemented?
3. Medications* Background: drug, dose, route, frequency? When was it last administered?* Breakthrough analgesia

Question 6

Describe the pain ladder

Answer 6

1. Mild pain
   =Non-opioid with or without adjuvant therapy
2. Mild to moderate pain
   =Weak opioid or multimodal fixed-dose opioids +/- nonopioid +/- adjuvant therapy
3. Moderate to severe pain
   =String opioid +/- nonopioid +/- adjuvant therapy

Question 7

Causes of fever in immediate postoperative period

Answer 7

-Reaction to anaesthetic
-Reaction to intra-operative blood products
-Pre-existing infection

Question 8

Causes of fever in day 3 post-operative period

Answer 8

-Atelectasis
-Infection
=Many possible sites!
=Wound
=Lines
=Metal /implants
=Chest
=Urine
=Others.

Question 9

Causes of fever day 5-7 post operative

Answer 9

-DVT/PE
-Infection

Question 10

Anaesthetic causes of post-operative confusion (delirium)

Answer 10

-Anaesthetic medications (inc. opioids and sedatives)
-Hypothermia
-Hypoxia
-Hypotension

Question 11

Surgical causes of delirium

Answer 11

-Pain
-Anaemia
-Infection
-Ileus

Question 12

Medical causes of delirium

Answer 12

-Electrolyte abnormalities (K+, Na+, Mg2+, Ca2+,PO43-)
-Low BM
-AKI
-Constipation
-Infection
-Acute urinary retention
-EtOH withdrawal

Question 13

Rare causes of delirium

Answer 13

-Intra-cranial event
-Malignant hyperthermia
-Others

Question 14

Investigation of post-operative delirium

Answer 14

-Medication review (sedatives, analgesia, steroids, anti-Parkinson)
-Bloods:
=Electrolytes, inc. Na+, K+, Mg2+,Ca2+, PO43-
=Glucose
-Others, as required

Question 15

Management of post-operative delirium

Answer 15

-Re-orientate
-Correct reversible causes (i.e., electrolyte abnormalities or infection)
-Treat
=Pain
=Constipation
=Dehydration
-Medication: Haloperidol (rarely needed)

Question 16

Risk factors for post-operative nausea and vomiting

Answer 16

20-30% patients

1. Patient (Apfel score)
   -Female
   -Non-smoker-Motion sickness or previous PONV
   -Post-operative opioid use
2. Anaesthetic
   -Inhaled anaesthetic agents
   -Prolonged anaesthetic
   -Intra-op opioid use
3. Surgical
   -Abdominal, gynaecological, intra-cranial and ear sugery
   -Prolonged operation

Question 17

Differentials for post-operative N&V

Answer 17

-Gastrointestinal
=Ileus
=Obstruction
= GI infections etc.
-Acidosis:
=Sepsis
=Uraemia (AKI)
=DKA
=Others
-CNS
=Raised ICP
-Aural (i.e., labyrinthitis)

Question 18

Management of post-operative N&V

Answer 18

-Multimodal analgesia, avoiding opioids where possible
-Ondansetron as the first-line anti-emetic
-Furthermore, the anaesthetic team will generally take prophylactic steps to reduce the risk of PONV becoming established

Question 19

Types of post-operative haemorrhage

Answer 19

-Primary: managed intra-operatively
-Secondary: 7-10 days, infection eroding vessel walls
-Reactive: 24 hours, due to failure of the intra-operative haemostatic methods

Question 20

What structures could be bleeding?

Answer 20

-Capillary beds
-Arterial
-Venous

Question 21

Factors in haemorrhagic shock classification

Answer 21

-Blood loss
-Pulse
-BP
-Pulse pressure
-CRT
-RR
-UO
-Mental status

Tennis scores (1-4)

Question 22

Blood investigations in haemorrhage

Answer 22

-VBG (quick Hb result)
-FBC (definitive Hb result)
-Coag (?coagulopathic)
-Lactate (?shock
- X-match (for blood transfusion)

Question 23

Management of haemorrhage

Answer 23

-Escalate
-?Activate major haemorrhage protocol
-Prescribe:
=IV fluids
=Blood products
=+/– Tranexamic acid
-Definitive:
=Depends on the aetiology