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Returning to Work in Anaesthesia, ed. Emma Plunkett, Emily Johnson and Anna Pierson. Published by Cambridge University Press. © Cambridge University Press 2016.

This chapter provides a refresher of some common clinical scenarios facing anaesthetists for general surgical, urological and gynaecological lists. It also includes a question on Enhanced Recovery Protocols which are well established for general surgical patients, but expanding into other specialties and another which discusses information from the organizational report from the National Emergency Laparotomy Audit. Whilst the national data will be published in due course, your hospital’s data can help to shape your local systems and it will be something worth finding out about if relevant to your area of practice.

General: epidural analgesia for laparotomy

Consider the following general surgical patients. In which patient(s) would you consider siting an epidural? What would be your analgesic plan for the other(s)?

a) 51-year-old, emergency laparotomy for bowel perforation, systemically well, no significant past medical history

b) 80-year-old, emergency laparotomy for bowel perforation, systemic inflammatory response syndrome (SIRS), pyrexial 39 °C, WBC 22 × 10⁹/l

c) 74-year-old, elective open hemicolectomy, significant IHD and chronic obstructive pulmonary disease (COPD)

d) 35-year-old, emergency laparotomy for Crohn’s abscess, previously intolerant of opioids

Answer: Both c) and d) are suitable candidates for an epidural as the benefits are likely to outweigh the risks. An epidural is contraindicated in b) because of the risk of sepsis. An alternative regional technique may be more suitable in a).

Advantages: epidural analgesia for major abdominal surgery has traditionally been seen as gold-standard care. An epidural can provide superior analgesia and patient satisfaction when compared with alternatives such as opioid PCAs. However, few studies have compared more modern multimodal approaches with epidurals. Good analgesia allows for early mobilization (providing that lines, monitors etc. allow for this) and avoids opioid-related side effects.

Epidurals are known to obtund the stress response to surgery although the theoretical benefits to patients have not been consistently proven. The incidence and duration of post-operative ileus is reduced, and return of normal gastrointestinal function is faster. It is widely accepted that epidural analgesia reduces pulmonary complications in high-risk patients; the effects on cardiovascular complications are less conclusive.

Disadvantages: These include hypotension (which can lead to excess fluid administration and additional complications if managed inadequately) and motor block, both of which may cause reduced mobility.

The risks of an epidural are not insignificant and should be considered in view of the likely benefits. Severe complications include vertebral canal haematomas, spinal cord ischaemia, vertebral canal abscess and other neurological injury. NAP3 identified the risk of permanent damage of between 1 in 24 000 and 1 in 54 000 cases. Contraindications to siting an epidural include systemic sepsis and those with an increased risk of bleeding, whether pharmacological or pathological. Careful multidisciplinary team management is vital in order to reduce risks, identify potential complications and maximize benefits.

Alternatives: There are a number of regional alternatives to epidural analgesia; these include transversus abdominis plane (TAP) blocks, rectus sheath blocks and local anaesthetic infiltration. These can be single shot or an infusion or bolus regimen via a catheter. Systemic analgesics should be optimized, including consideration of NSAIDs and alternative analgesics such as ketamine, clonidine, pregabalin and IV lidocaine infusions.

In conclusion, most experts agree that there is still a role for well-managed epidural analgesia in major abdominal surgery, provided that the risks and benefits have been carefully considered on an individual basis. Examples where an epidural may be favoured include the high-risk, co-morbid patient undergoing high-risk surgery and patients in whom opioids need to be avoided. In patients outside of these categories, an alternative regional technique should be considered as part of a multimodal regime.

General: laparoscopic bowel surgery

You have anaesthetized a 50-year-old female who is currently in the Trendelenburg position undergoing a laparoscopic hemicolectomy. The surgeon has insufflated the abdomen with gas and is midway through the operation when you notice that the patient has become bradycardic with a heart rate of 30 bpm. The gas insufflation pressures are >30 mmHg.

What is the most likely cause of her bradycardia?

The bradycardia is most likely to be secondary to vagal stimulation from peritoneal distension.

What are safe insufflation pressures for establishing a pneumoperitoneum?

The pneumoperitoneum is established by insufflating the abdomen with gas at pressures of 15 to 20 mmHg. A pressure of >30 mmHg is excessive: decompression of the abdomen is indicated.

What are the complications associated with laparoscopic surgery?

Problems associated with gas insufflation

i) Reduced cardiac output. Compression of the inferior vena cava reduces preload and may lead to a decrease in cardiac output and subsequent decrease in arterial pressure, particularly if the patient is hypovolaemic. As intra-abdominal pressure increases, systemic vascular resistance is increased owing to both mechanical compression of the abdominal aorta and production of neuro-humoral factors such as vasopressin and activation of the renin–angiotensin–aldosterone axis.

ii) Bradycardia secondary to vagal stimulation from peritoneal distension.

iii) Gas embolism secondary to high insufflation pressures or inadvertent direct injection of gas into a vessel leading to circulatory collapse.

iv) Abdominal distension resulting in diaphragmatic splinting and increased intrathoracic pressure. This leads to a reduction in pulmonary compliance and functional residual capacity. The end result is V/Q mismatching and hypoxaemia.

v) CO₂ absorption resulting in a gradual rise in EtCO₂.

vi) Surgical emphysema and pneumothorax.

vii) Shoulder tip pain secondary to diaphragmatic irritation from intra-abdominal gas.

Trauma associated with instruments

i) Puncture of a viscus such as stomach or bowel. The stomach is especially at risk if it has been distended after bag and mask ventilation.

ii) Vascular trauma involving the abdominal aorta, inferior vena cava and other great vessels.

Problems associated with positioning

i) Reverse Trendelenburg position (head up) can lead to hypotension and cerebral hypoperfusion.

ii) Trendelenburg position (head down) can result in cerebral oedema, vocal cord oedema and retinal detachment after prolonged operations.

iii) Compartment syndrome can result from impaired arterial perfusion to raised lower limbs, compression of veins by leg supports and reduced femoral drainage secondary to the pneumo-peritoneum.

General: emergency laparotomy

Approximately 30 000 patients undergo an emergency laparotomy each year in England and Wales. Several studies in recent years have shown that post-operative complications and even death are common, with 15% of all patients dying within a month of having an emergency laparotomy.

What measures could lead to the improved management of this group of patients?

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