COMPARISON OF INCREMENTAL SPINAL ANAESTHESIA USING A 32-GAUGE CATHETER WITH EXTRADURAL ANAESTHESIA FOR ELECTIVE CAESAREAN SECTION

Forty-three mothers who had requested regional anaesthesia forelective Caesarean section were allocated randomly to receiveeither extradural anaesthesia with pH-adjusted 2% lignocainewith 1/200 000 adrenaline, or incremental spinal anaesthesiausing a 32-gauge catheter with 0.5% plain bupivacaine. Incrementsof lignocaine or bupivacaine were given with the aim of achievinga block from T4 to S5. The spinal catheter was quicker to place(median 3 min, range 1–45 min, compared with median 10min, range 1.5–50 min) and spinal anaesthesia was quickerto establish (median 20 min, range 10–46 min comparedwith median 48 min, range 15–59 min) compared with theextradural technique. The maximum height of the spinal blockwas significantly higher (median T3–4, range T5–T3)than the extradural group (median T5, range T6–T3). Thetotal dose of intrathecal 0.5% bupivacaine was unpredictable,with a mean dose of 2.7 ml and a range between 1.5 ml and 7.4ml. Haemodynamic stability and the quality of the block weresimilar between the groups. There were two mild spinal headachesin the spinal group. All the spinal catheters were removed intact.