British journal of anaesthesia
-
Ocular microtremor (OMT) is a fine high frequency tremor of the eyes caused by extra-ocular muscle activity stimulated by impulses emanating in the brain stem. Several studies have shown that the frequency of this tremor is reduced in patients whose consciousness is reduced by anaesthesia or head injury. Therefore, OMT may possibly be used to determine depth of anaesthesia. ⋯ OMT activity was reduced progressively at predicted plasma concentrations of propofol of I and 2 microg ml(-1) and then plateaued between 3 and 5 microg ml(-1). There was a significant difference between the last awake OMT recording and the first recording at loss of consciousness (P < 0.001). OMT recording holds promise as a practical indicator of the depth of anaesthesia.
-
Estimation of changes in cardiac output from the arterial blood pressure waveform in the upper limb.
We have developed a new pulse contour cardiac output (PulseCO) algorithm based on frequency analysis studies of the arterial system. PulseCO was compared with thermodilution cardiac output (TDCO) in 10 patients undergoing cardiac surgery. Results from one patient were unsuitable for analysis. ⋯ Least squares regression gave y = 0.71 x (r2 = 0.70) and the limits of agreement were from -21% to +25%. After phenylephrine had been given to five patients, PulseCO showed an increase in systemic vascular resistance consistent with the known pharmacological actions of the drug. The PulseCO algorithm was incorporated into a computer program that acquires arterial pressure data from an analogue-to-digital converter and displays beat-to-beat trend values.
-
Randomized Controlled Trial Clinical Trial
Analgesic efficacy of tramadol 2 mg kg(-1) for paediatric day-case adenoidectomy.
We studied the analgesic efficacy of tramadol 2 mg kg(-1) for post-operative analgesia after day-case adenoidectomy in children aged 1-3 yr. Eighty children were allocated randomly to receive tramadol 2 mg kg(-1) i.v. or placebo immediately after induction of anaesthesia. Anaesthesia was induced with alfentanil 10 microg kg(-1) and propofol 4 mg kg(-1) followed by mivacurium 0.2 mg kg(-1) for tracheal intubation. ⋯ Forty-five per cent of children receiving tramadol did not require post-operative analgesia at all compared with 15% of children receiving placebo (P = 0.003). Recovery times and the incidence of adverse effects were similar in the two groups in the recovery room and at home. The requirement for rectal ibuprofen at home did not differ between groups.
-
Randomized Controlled Trial Clinical Trial
Antinociceptive properties of neurosteroids IV: pilot study demonstrating the analgesic effects of alphadolone administered orally to humans.
Fourteen patients scheduled for orthopaedic knee reconstruction surgery were enrolled in a prospective, double-blind, randomized study in which they received alphadolone (25-500 mg, n = 9) or placebo (lactose, n = 5) given orally 1 h after operation. All the subjects received a standardized general anaesthetic and the same type of surgery followed by physiotherapy using a continuous passive movement machine. Morphine was administered intravenously after operation by patient-controlled analgesia. ⋯ The experiences of these side-effects were all rated as none, mild or moderate. Orally administered alphadolone caused statistically significant reductions in morphine use and simultaneous highly significant reductions in pain scores. We conclude that alphadolone is a useful analgesic in humans when given by the oral route.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Intrapartum epidural catheter migration: a comparative study of three dressing applications.
We compared three types of catheter fixation application for their ability to minimize the incidence and magnitude of epidural catheter movement during labour. Patients were randomized to have their epidural catheter secured by a Tegaderm dressing (group T; n = 35), a Tegaderm dressing plus filter-shoulder fixation (group F; n = 39), or a Niko Epi-Fix dressing (group N; n = 37). ⋯ Outward movement of the catheter was greatest when a Niko Epi-Fix was used (P < 0.01). Concerning minimization of displacement of the epidural catheter per se, only a Tegaderm dressing with additional filter-shoulder fixation proved more effective than using a Niko Epi-Fix dressing (P < 0.05).