ERYTHROCYTE COUNTS IN THE CEREBROSPINAL-FLUID ASSOCIATED WITH CONTINUOUS SPINAL-ANESTHESIA

Continuous spinal anaesthesia technique can be associated with peridur al haemorrhage due to blood vessel damage caused by the needle or the catheter. We studied whether thrombosis prophylaxis or anticoagulation medications increase the risk of subarachnoid haemorrhage when contin uous spinal anaesthesia is used. Twenty arthroplasty patients received low-molecular-weight heparin preoperatively and twenty-two vascular s urgery patients received heparin (100 IU kg(-1)) peroperatively; eight of the latter patients were an regular preoperative antiplatelet medi cation. Twenty-four prostate surgery patients, not exposed to heparin or other drugs affecting coagulation, served as controls. A 22-gauge s pinal catheter was used and bupivacaine was injected through the cathe ter. Within the following 24 hours, 4-5 cerebrospinal fluid samples we re collected for erythrocyte counts. In the arthroplasty and the vascu lar group there were five patients each and in the control group seven patients with more than 100 X 10(6) l(-1) erythrocytes in at least on e of the samples. The highest erythrocyte count was 23900 X 10(6) l(-1 ) in a control patient. The 22-hour sample was blood-ringed (erythrocy tes >1000 X 10(6) l(-1)) in two patients in the arthroplasty group, in one patient in the vascular group and in four patients in the control group. In spite of the haemorrhages detected in this study, no relate d neurological symptoms or other serious consequences were observed. T he risk of subarnchnoid haemorrhage was not increased by drugs affecti ng coagulation.