British journal of anaesthesia
-
Randomized Controlled Trial Comparative Study Clinical Trial
Haemodynamic effects of the phosphodiesterase inhibitor enoximone in comparison with dobutamine in esmolol-treated cardiac surgery patients.
In a randomized study, the haemodynamic effects of the new phosphodiesterase-III-inhibitor, enoximone, were compared with dobutamine in acutely beta-adrenoceptor blocked patients. Twenty patients scheduled for aorto-coronary bypass grafting suffering from tachycardia (heart rate (HR) greater than 100 beat min-1) were treated by infusion of esmolol, an ultra-short acting, selective beta 1-blocker. Twenty minutes after the start of esmolol, either enoximone 0.5 mg kg-1 as a bolus (n = 10) or dobutamine 5 micrograms kg-1 min-1 was administered. ⋯ Cardiac index (CI) was decreased also. Enoximone increased Cl (+35%) and dP/dtmax (+39%) significantly, while no change in dobutamine-treated patients was observed. Systemic vascular resistance increased only in the dobutamine group (+44%).
-
Randomized Controlled Trial Clinical Trial
Influence of obesity on the spread of spinal analgesia after injection of plain 0.5% bupivacaine at the L3-4 or L4-5 interspace.
Spinal anaesthesia was compared in 40 obese patients (increased body mass index (BMI] and 40 patients with normal BMI when 3 ml of plain 0.5% bupivacaine was injected at either the L3-4 or L4-5 interspace. More extensive cephalad spread of sensory block was achieved in patients with increased BMI compared with patients with normal BMI after injection at both L3-4 and L4-5 (P less than 0.05). ⋯ Good anaesthesia was produced in all patients for orthopaedic surgery of the lower extremity. In an obese patient it is recommended that plain bupivacaine be administered at L4-5 instead of L3-4 when extensive spread of the block is to be avoided.
-
A retrospective study of serious non-fatal complications of extradural block in obstetric practice was carried out using a postal questionnaire. Two hundred and three obstetric units in the United Kingdom (responsible for 2,580,000 deliveries from 1982 to 1986 inclusive) responded. A total of 505,000 extradural blocks were performed, 84% for relief of pain in labour and 16% for Caesarean section. ⋯ Neuropathy involving a single spinal nerve, acute toxicity from the local anaesthetic, and problems associated with accidental dural puncture were the commonest complications. This investigation indicates the need for a prospective study. Although rare, serious complications could be reduced further by meticulous technique, while early diagnosis and treatment of untoward events would reduce the incidence of permanent disability.
-
We have studied the effect of i.v. midazolam on median nerve somatosensory evoked potentials (SSEP) in 10 unpremedicated adults. Anaesthesia was induced with midazolam by bolus administration (0.2 mg kg-1) followed by infusion (5 mg h-1). The latency and amplitudes of the SSEP responses over the second cervical vertebrae (SC2) and sensory cortex (P17, N20, P25) were recorded before and for 10 min after induction. ⋯ Small but statistically significant increases in latency of the cortical N20 (P less than 0.005) and P25 (P less than 0.001) waves and interwave conduction times of SC2 to P25 (P less than 0.005) and N20 to P25 (P less than 0.021) were observed. Cortical amplitude (N20-P25) decreased significantly (P less than 0.012), to approximately 60% of baseline. These results demonstrated that midazolam produced a depression of cortical SSEP amplitude without clinically significant alterations in latency.