Anaesthetics

Question 1

What is neuroleptic malignant syndrome?

Answer 1

This is a condition seen following adminstration of anaesthetic agents halothane or suxamethonium.

It is characterised by hyperpyrexia and muscle rigidity. Due to excessive Ca2+ release from sarcopasmic riticulum of skeletal muscle due to autosomal dominant defect.

Question 2

What are the investigations in malignant hyperthermia?

Answer 2

• CK (raised)
• Contracture tests with halothane and caffeine

Question 3

Which drug is key in management of malignant hyperthermia?

Answer 3

Dantrolene IV (prevents Ca2+ release from sarcoplasmic reticulum.

Question 4

For which procedures is pharmacolociage VTE prophylaxis recommended for all patients?

Answer 4

Elective Hip:

• LMWH for 10 days followed by aspirin (75mg) for a further 28 days
• OR LMWH for 28 days + TED stockings
• OR Rivaroxiban

Elective knee:

• Aspirin for 14 days
• OR LMWH for 14 days combined wtih TED stockings
• OR Rivaroxiban

Fragility fractures of pelvis, hip, proximal femur:

• LMWH or fondaparinux until the person no longer has reduced mobility

Question 5

What type of surgery is ring block used in?

Answer 5

Ring block refers to anaesthetic technique used to numb a finger, e.g. for ingrown nail operations. the nerves on both sides of the finger are infiltrated, leading to a “ring-like” blockage.

Question 6

If a patient is steroid dependent and takes regular prednisolone, how do you alter the dose during surgery?

Answer 6

Patients that are steroid dependent taking prednisolone should have hydrocortisone. Rule of thumb:

• Minor procedure under local: no supplementation required
• Moderate procedure: 50mg hydrocortisone before induction and 25mg every 8h for 24h
• Major surgery: 100mg hydrocortisone before induction and 50mg every 8h for 24h, thereafter halving dose every 24h until maintenance dose reached.

Question 7

What is the most common site for intraosseus access?

Answer 7

Proximal tibia

Question 8

How long prior to surger should the COCP be disoncinued?

When can it be restarted?

Answer 8

Should be stopped 4 weeks before, can be restared 2 weeks after.

Question 9

Which muscle relaxant is used in rapid sequence induction of anaesthesia?

Answer 9

A depolarising muscle relaxant such as suxamethonium is used for rapid sequence induction, as it has the fastest onset.

Question 10

What is a rapid sequence induction and give an example for when it is used.

Answer 10

Rapid sequnce induction is where th patients is not ventilated form administration of the drugs to tracheal intubateion.

This is used when the stomach hasn’t been emptied (e.g. in trauma surgery) as it reduces the risk of aspiration.

Question 11

What is a contraindication to use suxamethonium?

Answer 11

• Suxamethonium is contraindicated for patients with penetrating eye injuries or acute narrow angle glaucoma, as suxamethonium increases intra-ocular pressure.
• Patients with high potassium: suxamethonium may cause hyperkalaemia. It is therefore often containdicated in burns/trauma patients.

Question 12

When is ketamine used as an anesthetic agent?

Answer 12

Ketamine may be used for induction of anaesthesia in patients that are haemodynamically unstable as it produces little myocardial depression.

t may be used for emergency procedures outside the hospital environment to induce anaesthesia for procedures such as emergency amputation.

Question 13

How many units of blood should be corssmatched for open cystectomy?

How many for laparoscopic cystectomy?

Answer 13

4-6 depending on local guidelines.

Laparoscopic: G&S is enough.

Question 14

How many units of blood should be corssmatched for AAA repair?

Answer 14

4-6 depending on local guidelines.

Question 15

How many units of blood should be corssmatched for salpingectopy, ruptured ectopic, total hip replacement?

Answer 15

2 units

Question 16

Describe the management of post-operative ilues.

Answer 16

Conservative with nasogastric tube insertion for stomach decompression for symptom control and placing the patient nil by mouth to allow bowel rest. The recommencement of fluids/light diet should be in stages and guided by the clinical state of the patient.

Question 17

Which fluids does NICE recommend to use to clean wounds post-OP?

Answer 17

Up to 48 hours: Sterile saline

From 48 hours onwards, patients may shower and tap water may be used.

Question 18

In which situations can you not use a laryngeam mask airway?

Answer 18

• Patient not fasted (as doesn’t protect from aspiration)
• Cannot be used to provide high pressure ventilation

Question 19

SUmmarise the immediate management of a DIC during labour.

Answer 19

Clotting studies and a platelet count should be urgently requested and advice from a haematologist sought. Up to 4 units of FFP and 10 units of cryoprecipitate may be given whilst awaiting the results of the coagulation studies.’

Question 20

What are early causes of post-OP pyrexia?

Answer 20

• Blood transfusion
• Cellulitis
• UTI
• Physiological systemic inflammatory reaction
• Pulomnary atelectasis

Question 21

What are late causes of post-OP pyrexia?

Answer 21

• VTE
• Pneumonia
• Wound infection
• Anastomotic leak

Question 22

What is the diagnosis of choice for suspected anastomotic leak?

Answer 22

Abdominal CT.

Question 23

What is the most appropriate way to administer TPN?

Answer 23

Central line

Question 24

What medications are known to slow bone healing?

Answer 24

• NSAIDs
• Immunosuppressives
• Steroids
• Anti-neoplastic drugs

Question 25

What electrolyte/acid-base abnormality may occur when giving too much normal saline?

Answer 25

xcessive administration of sodium chloride is a recognised cause of **hyperchloraemic acidosis** and therefore Hartmans solution may be preferred where large volumes of fluid are to be administered.

Question 26

Describe the immediate management of wound dehiscnece.

Answer 26

* Apply sterile gauze soaked in 0.9% saline. * Call senior help immediately for theatre.

Question 27

What is a complication of long-term intubation?

Answer 27

Long term mechanical ventilation in trauma patients can result in **tracheo-oesophageal fistula formation**. The pressure arising from the endotracheal tube on the posterior membranous wall of the trachea can result in ischaemic necrosis that also involves the anterior wall of the oesophagus. This results in TOF formation.

Question 28

Which anaesthetic agent is hepatotoxic and should therefore be avoided in patient with hepatic dysunction?

Answer 28

Halothane. Halothane is hepatotoxic. Despite this it remains in mainstream use. It should be avoided in patients with hepatic dysfunction, and scavengers should be used in theatres as accumulation of the drug may be injurious to theatre staff.

Question 29

What are the symptoms of local anaesthetic toxicity?

Answer 29

* Circumoral and/or tongue numbness. * Metallic taste. * Lightheadedness. * Dizziness. * Visual and auditory disturbances (difficulty focusing and tinnitus) * Disorientation. * Drowsiness.

Question 30

How can local anaesthetic toxicity be treated?

Answer 30

Local anesthetic toxicity can be treated with **IV 20% lipid emulsion**

Question 31

What is the underlying pathophysiology of suxamethonimum apnoea?

Answer 31

**Pseudocholinesterase** **deficiency** (also known as suxamethonium apnoea) is a rare abnormality in the production of plasma cholinesterases. This leads to an increased duration of action of muscle relaxants used in anaesthesia, such as suxamethonium. Respiratory arrest is inevitable unless the patient can be mechanically ventilated safely while waiting for the circulating muscle relaxants to degrade.

Question 32

What are components of the WHO surgical safety checklist?

Answer 32

* Patient has confirmed: Site, identity, procedure, consent * Site is marked * Anaesthesia safety check completed (machine/medications) * Pulse oximeter is on patient and functioning * Does the patient have a known allergy? * Is there a difficult airway/aspiration risk? * Is there a risk of \> 500ml blood loss (7ml/kg in children)?

Question 33

Which ventilation technique can be used to facilitate long-term weaning?

Answer 33

Tracheostomies.