Effects of age on the neural blockade and the pharmacokinetics of hyperbaric bupivacaine in continuous spinal anaesthesia with the Spinocatheter

Cristina Berteanu¹, M.Gielen²
1) Spitalul Universitar de Urgenta Bucureşti, România
2) Spitalul Universitar Saint Radboud, Nijmegen, Olanda

Abstract

Effects of ageing were studied on the neural blockade and the pharmacokinetics after subarachnoid administration by a system of continuous spinal anaesthesia (Spinocath catheter 22 G) of 3 ml bupi-vacaine HCl 0.5 % în 8% glucose in 2 groups of 15 male patients, between 20 and 60 years and older than 60 years, respectively. The blockade was performed with the patient in the sitting position. Two minutes after the injection the patient was placed in the supine position. The time to maximum cephalad spread and the upper level of analgesia increased with advancing age, whereas the time to onset of motor blockade decreased with advancing age. Effects of age on the total duration of analgesia and motor blockade could not be demonstrated. Age had no effect on the peak plasma concentration of bupivacaine. The time to peak concentration and the terminal half-life increased, whereas the total plasma clearance decreased with advancing age. Postoperative analgesia was achieved in the first 72 hours with 200 µg morphine at 12 hours, or with morphine 100 µg and bupivacaine 0.25% 2 ml at every 12 hours, or administration right after surgery of 1 ml bolus bupivacaine 0.25% followed by a continuous infusion of 10 ml/24h. The quality of postoperative analgesia was tested with visual analogue scale 30 min, before and after, the injection and it was found to be good and very good. The patients were examined for neural complications, infections and postdural puncture headache (PDPH), on the first, third and fifth day after surgery. No cauda equina syndrome arose, or other permanent neurological sequelae. PDPH was absent. With regard to the incidence of infections, the leucocyte, protein and glucose concentration in CSF did not change significantly.

Keywords: ageing, neural blockade, pharmaco-kinetics, continuous spinal anaesthesia, hyperbaric bupivacaine

Efectele vârstei asupra blocului neural şi farmacocineticii în contextul anesteziei spinale continue cu cateter Spinocath şi bupivacaină hiperbară

Jurnalul Român de Anestezie Terapie intensivă 2006 Vol.13 Nr.2, 89-96