Anaesthesia for Orthopaedic Surgery
One in five operations in the United Kingdom is for orthopaedic, spinal or trauma surgery. Anaesthesia for trauma surgery is discussed in Chapter 37. This chapter provides a framework for the conduct of anaesthesia for orthopaedic surgery.
THE PATIENT POPULATION
Concurrent Drug Therapy
Many young healthy patients presenting for orthopaedic surgery do not take concurrent medication. However, use of analgesics is very common in the orthopaedic population because of the painful nature of their disease process. Concurrent therapy with antihypertensive, antianginal, antidepressant or cholesterol-lowering medication is common in older patients presenting for orthopaedic surgery. These patients often present for arthroplasty and this major procedure may place significant demands upon their physiological reserves. Preparation of the patient taking these drugs is discussed in detail in Chapter 18. Patients may also be using orthopaedic disease-modifying drugs such as methotrexate, steroids and gold.
TECHNIQUES OF ANAESTHESIA
Regional Anaesthesia
Peripheral nerve block is commonly used as a sole technique for many procedures, with the advantages of excellent pain relief, reduction of surgical stress, avoidance of complications of general anaesthesia and earlier discharge in the day-case setting. Peripheral surgery in ‘high-risk’ patients may also be carried out under peripheral nerve block to avoid the potential complications of general anaesthesia or central neuraxial block. Patients report a high degree of satisfaction following surgery carried out using this form of anaesthesia. Table 28.1 shows the sites at which surgery may be performed in association with specific nerve blocks. This form of anaesthesia requires a high level of expertise and an understanding of the issues of managing a conscious patient during surgery.
Intravenous regional anaesthesia (IVRA) is suitable for manipulation of fractures and brief operations (less than 30 min) on the forearm and lower leg. It is technically easy to perform but fatalities have occurred as a result of a large dose of local anaesthetic reaching the systemic circulation. Before performing IVRA, it is essential to understand how the risk of complications may be minimized and how they may be treated if they occur. Details of the technique and safety precautions are described in Chapter 24.