We have studied in 22 patients the effect of adding hyaluronidase to bupivacaine during axillary brachial plexus block (BPB) in a double-blind design. Patients received BPB using bupivacaine 2 mg kg-1 with adrenaline 1 in 200,000, either with or without hyaluronidase 3000 iu, in a volume of 0.5 ml per 2.54 cm of the patient's height. The use of hyaluronidase did not increase the speed of onset of anaesthesia or reduce the incidence of inadequate nerve block. Hyaluronidase produced a significant reduction in the duration of anaesthesia. Changes in grip strength and skin temperature were useful in assessing the onset and progress of BPB.

SummaryThe present study was designed to assess the incidence of pain when methohexitone was administered to 35 depressedpatients who had electroconvulsive therapy, and to determine whether the use of lignocaine could modijy this, without affecting seizure duration. The same patients were studied during three separate treatment sessions; they received either methohexitone alone or mixed with, or preceded by, lignocaine 10 mg. Six (17%) patients spontaneously complained of pain during injection of methohexitone alone: the use of lignocaine prior to methohexitone reduced this to zero ( p < 0.05). A total of 49% patients reported pain during injection of methohexitone; the use of lignocaine either mixed with, or given prior to, methohexitone significantly reduced this to 23% and 20% respectively ( p < 0.05). Seizure duration was not significantly different during the three treatments. Key wordsAnaesthetics, intravenous; methohexitone. Electroconvulsive therapy.Methohexitone has been described as the drug of choice for anaesthesia for electroconvulsive therapy (ECT).'.* However, 40-60% patients experience pain during its injection into a vein on the dorsum of the hand prior to surgery,'-5 but the incidence in patients who have anaesthesia for ECT is not known. Repeated anaesthesia is required for ECT treatment, and anticipation of pain on injection may be very distressing for patients, a pain which could be reduced if lignocaine is given with, or prior to, methohexitone.'~6The present study was designed to determine the incidence of pain during injection of methohexitone prior to ECT treatment, and to assess whether it could be reduced by the use of lignocaine. A bilateral generalised convulsion must be produced during ECT if treatment is to be beneficial.' The use of lignocaine prior to ECT is usually avoided,x because it reduces seizure duration and renders treatment less effe~tive.~ The effect of lignocaine on seizure duration was therefore also recorded during the present study. MethodsThirty-five patients who had a course of bilateral ECT for treatment of depression were included in the study, which was approved by the Hospital Ethics Committee. Eight male and 27 female unpremedicated patients, aged 18-80 years and who weighed 43-90 kg, were studied. Patients gave informed verbal consent to participate, and none receiving treatment under the provisions of the Mental Health Act were involved.Patients were studied during three consecutive ECT treatments over a period of 10-14 days, but not during the first treatment, because seizure duration is often prolonged at this time.I0 Concurrent medication was not altered during the study. Anaesthesia was induced with one of three regimens, the order of which was randomly selected for each patient. All subjects experienced all three methods of induction of anaesthesia on separate occasions.Methohexitone only. Venepuncture was performed using a 23-gauge butterfly needle inserted into a small vein on the dorsum of the hand. One millilitre 0.9% saline was injected, and venou...

SummaryA simple method of protamine titration using the Hemochron system was compared with an empirical dose protocol for reversal of heparinisation following cardiopulmonary bypass in 40 patients undergoing elective myocardial revascularisation. Protamine titration revealed a wide range for protamine requirement and resulted in a signiJcant reduction in protamine dose compared with the empirical dose protocol ( p < 0.01). Heparin reversal was assessed as adequate in all patients. The titration technique was easy and straightforward to use in the operating theatre Key wordsBlood, coagulation; protamine, heparin.Heparinisation is required for the safe performance of cardiopulmonary bypass, but at the end of the procedure, residual heparin needs to be reversed with protamine sulphate. Conventional protocols calculate the dose of protamine empirically, based on the patient's weight or the dose of heparin administered. There is considerable variation in the individual's response to heparin and protamine and this empirical approach cannot guarantee optimal heparin reversal.Protamine has well documented side effects.' Hypotension is common but may be limited by adequate maintenance of the cardiac filling pressure. Cardiac output is usually well maintained if left ventricular function is good.2 More serious reactions such as anaphylaxis or pulmonary vasoconstriction occur less frequently but may be catastrophic. Protamine causes thrombocytopaenia, may impair platelet aggregation, and exerts an anticoagulant effect due to an interaction with t h r~m b i n .~ It is therefore undesirable to give more protamine than is necessary for heparin reversal.Titration of the protamine requirement may allow more accurate dose calculation and thus avoid the problems of over-or underdosing. Recently, a simple titration method has been described using activated clotting time (ACT) mea~urernent.~ The use of sample tubes prefilled with fixed amounts of protarnine allows the construction of a twopoint dose-response line from which the required protamine dose can be calculated. However, this method has not been evaluated in a controlled clinical trial, nor with any laboratory tests, to assess the adequacy of heparin reversal. This study was designed to compare, in patients following cardiopulmonary bypass, the protamine dose determined from a similar, simple protamine titration slope with that calculated from an empirical method. MethodLocal ethics committee approval was obtained for this study. Informed consent was obtained from patients undergoing elective myocardial revascularisation operations. Patients presenting for reoperation, concomitant valve or left ventricular aneurysm surgery were excluded from the study, as were those who required the use of an intra-aortic counterpulsation device, a cell saver/haemoconcentrator or the administration of clotting factors during surgery. The anaesthestic technique was determined by the individual anaesthetist but the same type of cardiopulmonary bypass equipment was used in each case.A baseline...

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Cadaver/anatomy research, Level V.