Biomedical subjects

M Ben Ammar

Publications and source records attributed to M Ben Ammar.

7 recordsLinked to original sources

PubMed2002

[Spinal anesthesia in children: comparative study of hyperbaric bupivacaine with or without clonidine].

OBJECTIVE: To evaluate the effect of intrathecal clonidine in children. STUDY DESIGN: A prospective randomised study. PATIENTS AND METHODS: 45 children, 6 to 15 years old, were randomised in two groups; receiving either 0.5% hyperbaric bupivacaine or 0.5% hyperbaric bupivacaine added to clonidine 2 micrograms.kg-1. We assessed quality and length of motor and sensory blocks and side effects of clonidine: hypotension, bradycardia and sedation. RESULTS: Clonidine was associated with prolongation of motor block. 190 +/- 42 min vs 150 +/- 35 min (p < 0.01), but the difference was not significant. Postoperative analgesia was longer in clonidine group, 490 +/- 35 min vs 200 +/- 50 min (mean +/- SD), p < 0.001. Clonidine was associated with higher incidence of hypotension 54 vs 36% and bradycardia 30 vs 0%. CONCLUSION: These data suggest that intrathecal clonidine 2 micrograms.kg-1 is associated with extending duration of postoperative analgesia but with moderate side effects.

Adolescent↗

PubMed1989

Changes in ventilation, oxygen uptake, and carbon dioxide output during recovery from isoflurane anesthesia.

Recovery from inhalation anesthesia is often marked by the occurrence of postoperative tremor that resembles shivering, which is known to be associated with an increase in oxygen uptake (VO2), CO2 output (VCO2), and minute ventilation (VE). This study determined the time course of the ventilatory changes observed during the first hour of recovery from isoflurane anesthesia. Ten patients (ASA PS 1) scheduled for minor orthopedic surgery (knee arthroscopy) were included in this study. Anesthesia was induced with thiopental (5 mg/kg) and maintained with 70% N2O and isoflurane (1-2%) in oxygen, allowing spontaneous ventilation. In the recovery room, after N2O had been discontinued, patients were connected to a Beckman Metabolic measurement cart, which allowed a continuous monitoring of VE, VO2, VCO2, and PETCO2. Postoperative tremor was observed in all patients within 7.1 +/- 1.2 min (mean +/- SEM) after isoflurane discontinuation and was associated with a marked increase in the following: VO2, from 173 +/- 26 ml/min at the end of anesthesia to 457 +/- 88 ml/min; VCO2, from 149 +/- 18 ml/min at the end of anesthesia to 573 +/- 98 ml/min; and VE, from 6.8 +/- 0.7 l/min at the end of anesthesia to 16.6 +/- 2.8 l/min (values obtained 20 min after isoflurane discontinuation). In three patients during intense shivering, VO2, VCO2, and VE reached peak values higher than 800 ml/min, 1,300 ml/min and 30 l/min, respectively. This study shows that postoperative tremor following isoflurane anesthesia may be associated with prolonged and large increases in oxygen uptake, CO2 output, and minute ventilation.

Adolescent↗

PubMed1987