[Superselective spinal anesthesia for saphenectomy intervention. Comparison of 2 concentrations of hyperbaric bupivacaine].

BACKGROUND

High concentrations of intrathecal local anaesthetics may be neurotoxic. The purpose of this study was to compare the features of superselective spinal anaesthesia (ASS) obtained with an equivalent dose (5 mg) of 0.5% (available now also in Italy) and 1% hyperbaric bupivacaine.

METHODS

A prospective study was carried out on 100 patients undergoing saphenectomy, who were randomized into two groups to receive either 0.5% bupivacaine 1 ml (group A) or 1% bupivacaine 0.5 ml (group B). The anaesthetic solution was injected 1 ml/min at L2-L3 with an atraumatic needle. During dural puncture and following 20 minutes patients were held with the operative side down. In every patient were recorded: quality and level of analgesia on dependent (operative) and non dependent sides; motor-block at the 20th minute and 2nd, 3rd and 4th hours on both sides; reduction per cent of systolic artery pressure (SAP) and heart rate (HR), incidence of hypotension (SAP < 90 mmHg) and bradycardia (HR < 50 bts/min); recovery of deambulation and micturition and side effects.

RESULTS

Significant differences between the two groups have been found in: 1) number of thoracic segments blocked (3.22 vs 2.02); 2) motor block at the 2nd hour; 3) number of patients able to walk (19 vs 3) and to micturate (11 vs 3) at the 2nd hour.

CONCLUSIONS

0.5% hyperbaric bupivacaine can be successfully use in ASS; early regression of motor block is especially suitable for the requirements of day surgery.