Regional block and DVT prophylaxis

The last few years have seen increasing concerns among anaesthetistsabout the risks of pharmacological prophylaxis for thromboembolicdisease. Increased bleeding during or after surgery is one concern,but of greater significance is the possibility of an increasedpredisposition to haematoma formation when regional block isused. Most of the recent consideration of this problem has beenin relation to vertebral canal haematoma formation after centralnerve block. Some thought must be given also to the possibilityof haematoma formation after peripheral techniques when thetarget nerve is deeply placed so that pressure cannot be usedto control bleeding after needle insertion. However, this reviewwill be focused on vertebral canal haematoma.     

Regional anaesthesia in patients taking anticoagulant drugs

Many surgical patients are taking drugs that impair normal coagulation, and this causes concern about the risk of perioperative bleeding events. The anaesthetist is particularly concerned about compressive vertebral canal haematomas, which may occur after spinal or epidural anaesthetic techniques. Fortunately, the risk of this complication is very low. The major risk factors are coagulopathy or technical difficulties with the block. There is also concern about perineural haematomas, which may be associated with peripheral nerve blocks. This article attempts to put the risks of these complications into context, with reference to different classes of anticoagulant drugs.     

Low-dose heparin in femoral neck fractures

Heparin in low doses was given by subcutaneous injection to 25 patients with femoral neck fractures; a further 26 patients acted as a control group. Deep-vein thrombosis was diagnosed by the ¹²⁵I-fibrinogen test. Thrombosis occurred in 68 per cent of patients in the heparin group and in 50 per cent of the controls. The incidence of deep-vein thrombosis was not increased when operative fixation of the fracture was delayed for more than 24 hours. It appears that the initial thrombosis may occur very soon after the fracture and as a direct response to the trauma, rather than to the operation itself.     

Intertrochanteric femoral fractures. Mechanical failure after internal fixation

In a prospective study we assessed the causes of mechanical failure in a series of 230 intertrochanteric femoral fractures which had been internally fixed with either a sliding hip screw or a Küntscher Y-nail. The overall rate of mechanical failure was 16.5%; cutting-out of the implant from the femoral head was the cause in three-quarters of the instances. Implants placed posteriorly in the femoral head cut out more often (27%) than those placed centrally (7%). The cut-out rate was also determined by the quality of the fracture reduction, but age, walking ability and bone density (assessed by the Singh grade and metacarpal indices) had no significant influence. We conclude that these fractures should be reduced as accurately as possible and it is imperative that the implant is placed centrally within the femoral head.     

Intertrochanteric fractures of the femur: a prospective study comparing the use of the Küntscher-Y nail and a sliding hip screw

This prospective randomized study has compared the use of the Küntscher-Y nail and a sliding hip screw in the treatment of intertrochanteric fractures of the femur. For patients whose general health was good, the use of the sliding hip screw was associated with a significantly lower 1-year mortality rate. The use of the sliding screw also resulted in a higher proportion of 1-year survivors regaining their prefracture level of mobility. There was no difference in the rates of cutting-out of the two implants but use of the Küntscher-Y nail was associated with a greater incidence of shortening.