Spinal anesthesia with a mixture of subtherapeutic doses of local anesthetic and opioid for hip surgery in elderly

C. Rusan¹, I. Acalovschi², D. Lucaciu³, S. Hopulele³
1) Clinica de Ortopedie şi Traumatologie, Cluj
2) Catedra ATI – UMF „Iuliu Haţieganu”, Cluj
3) Catedra Ortopedie şi Traumatologie – UMF „Iuliu Haţieganu”, Cluj

Abstract

Background. The results of a previous study demonstrated that 1.5 ml of 0.5% bupivacaine (7.5 mg) represents the appropriate volume for spinal anaesthesia in hip trauma surgery of elderly patients. Administered in the subarachnoidian space, at L2-L3, this dose/volume provided a high quality analgesia with minimal haemodynamic changes.

The aim of this study was to determine if the association of a local anaesthetic with an opioid in the limits of 1.5 ml volume: a) offers a better analgesia, b) modifies the haemodynamic profile, c) influences postoperative pain, d) influences the incidence of postoperative delirium in elderly patients.

Materials and methods. Spinal anaesthesia was performed in 60 patients, aged 75 to 101, for traumatic hip surgery. The patients were randomized in 3 groups of 20 patients : group 1 – 1.5 ml isobaric 0.5% bupivacaine (7.5 mg ); group 2 – 0.5 ml of 5% pethidine (25 mg) + 1 ml of saline; group 3 – 1,25 ml isobaric 0.5% bupivacaine (6.25 mg) + 0,25 ml pethidine 5% (12.5 mg). If systolic blood presure (SBP) dropped more than 25% of the preanaesthetic value, 5 mg of ephedrine was administered as many times as necessary to maintain the SBP above 75% of initial value. The following parameters were monitored: the onset, quality, duration and extension of the sensitive block, the intensity of the haemodynamic changes, the presence of the specific complications of subarachnoidian administered opioids (respiratory depresion, sickness, itching, pruritus, excesive sedation), the duration of postoperative analgesia and the incidence of postoperative delirium. The results were evaluated with the ANOVA and chi square tests, p < 0.05 being considered significant.

Results. The best sensitive block associated with the best haemodynamic stability was noted in the third group, in comparison with the first and second group. Postoperative analgesia was significantly longer in the second and third groups compared with the first one. The association of pethidine reduced the incidence of postoperative delirium.

Conclusions. The association of an opioid (pethidine) with a local anaesthetic (bupivacaine) in subtherapeutic doses for spinal anaesthesia in hip trauma surgery of elderly patients, offers a very good quality of sensitive block, stable haemodynamic parameters, a prolongued post-operative analgesia and a reduced incidence of postoperative delirium.

Key words: spinal anesthesia, bupivacaine, pethidine, mixture, hip surgery, elderly

Anestezia subarahnoidiană cu amestec de anestezic local şi opioid, în doze subterapeutice, pentru chirurgia şoldului la vârstnici

Jurnalul Român de Anestezie Terapie intensivă 2004 Vol.11 Nr.1, 33-38