Hyperkalaemia and cardiac arrest after the use of suxamethonium in intensive care

We read with interest the report by A.R. Michie e f nl. (ilnnesrhesia 1988; 43: 9 6 9 ) . Subarachnoid anaesthesia has been used recently in our hospital for Caesarean sections with very satisfactory results. Our practice differs from that of the authors in several respects. We preload our patients with 500 ml compound sodium lactate solution and 500 ml modified gelatin (Gelofusine) before the subarachnoid block is established. Intramuscular ephedrine 30 mg is given prophylactically 15-30 minutes before the spinal block. The patient is placed in the left lateral position and 1.5-2.0 ml 0.5% hcavy bupivacaine are injected at L, or L3-, interspace through a 26-G spinal needle, using minimal barbotage. The patient is placed supine immediately with right lateral t i l t and the extent of the block assessed with ethyl chloride spray. The table is then tilted to obtain a block to T, and thc table returned to a left lateral tilt when surgery starts. This technique has been used on 40 patients with satisfactory analgesia in all cases. Hypotension (systolic 100 mmHg or symptomatic) in 23% of patients was rapidly corrected with intravenous increments of ephedrine; in two patients the hypotension was serious. Postoperative headache was minimised by taking great care to ensure that thcre was only a single puncture of the dura and keeping the patients flat for 12 hours after the Caesarean section. We considcr subarachnoid anaesthesia to have significant advantages over epidural anaesthesia for Caesarean section. in particular because of the rapid onset of action and the more profound analgesia produced. Thesc qualities arc of particular value for emergency Caesarean sections. We agree with the authors. however, that its main disadvantage is in thc variable and short duration of action of 0.5% heavy bupivacaine. It is not used if' operative difficulties are envisaged.