Anaesthesia for hip surgery in the elderly.

Surgical repair of hip fracture and total hip arthroplasty are primarily performed on elderly patients. Patients presenting for hip fracture surgery have a high prevalence of preoperative medical problems and may require medical stabilization before surgery. Regional anaesthesia for hip fracture repair may be contraindicated due to perioperative pharmacologic prophylaxis for deep venous thrombosis. The use of regional anaesthesia increases the magnitude and frequency of hypotensive episodes when compared with general anaesthesia. Intraoperative blood losses, averaging 250-300 ml, are not affected by anaesthetic technique. Following hip fracture surgery under spinal anaesthesia, patients exhibit better oxygenation in the early postoperative period than those after general anaesthesia. The frequency of postoperative confusion is unrelated to anaesthetic technique. The incidence of deep venous thrombosis is reduced following spinal anaesthesia as compared with general anaesthesia. The one-month mortality rate, approximately eight per cent, is unrelated to anaesthetic technique. Spinal, epidural and general anaesthesia have been used successfully for total hip arthroplasty. Intraoperative blood loss of 0.5-1.5 litres is reduced with regional anaesthesia. General anaesthesia with controlled hypotension also significantly reduces blood loss. Intraoperative instability with hypoxaemia, hypotension and cardiac arrest may follow impaction of the femoral prosthesis and are related to absorption of acrylic cement monomers and pulmonary embolism of fat, air, and platelet-fibrin aggregates. Postoperative deep venous thrombosis is common and the incidence may be reduced with epidural anaesthesia. Operative mortality is less than one per cent and pulmonary embolism is the commonest cause of death.(ABSTRACT TRUNCATED AT 250 WORDS)