British journal of anaesthesia
-
Randomized Controlled Trial Comparative Study Clinical Trial
Comparison of extradural ropivacaine and bupivacaine.
Ropivacaine, a new long acting amide type local anaesthetic, was compared with bupivacaine in a randomized double-blind study. One hundred and ten patients undergoing extradural anaesthesia received a test dose of 3 ml of 1% lignocaine with adrenaline which was followed by 15 ml of one of five solutions: 0.5, 0.75 or 1.0% ropivacaine or 0.5 or 0.75% bupivacaine. There was little difference between the groups with respect to speed of onset or sensory block. ⋯ Increasing concentration of both drugs resulted in greater degree and longer duration of motor block. Ropivacaine produced a slower onset, shorter duration and less intense motor block than the same concentration of bupivacaine. The cardiovascular changes were similar in all groups.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Priming of cardiopulmonary bypass with human albumin or Ringer lactate: effect on colloid osmotic pressure and extravascular lung water.
We have undertaken a randomized study on 20 patients undergoing coronary artery bypass surgery in order to determine the influence of cardiopulmonary pump prime solutions on colloid osmotic pressure and extravascular lung water. Crystalloid priming with Ringer lactate was compared with an albumin solution of nearly physiological colloid osmotic composition (4%). ⋯ The more pronounced decrease in colloid osmotic pressure and in transcapillary gradient (difference between colloid osmotic pressure and pulmonary capillary wedge pressure) in the Ringer lactate group was associated with a significant increase in extravascular lung water (by 60%) in the postoperative period; the human albumin group, however, showed only a slight tendency to increased lung water. There were no differences in haemodynamic or respiratory states after operation.
-
Randomized Controlled Trial Clinical Trial
Ingestion of clear fluids is safe for adolescents up to 3 h before anaesthesia.
We have studied the effect of ingestion of unlimited clear fluids by adolescents up to 3 h before anaesthesia to determine the effect this fluid ingestion would have on thirst, hunger and gastric contents at induction of anaesthesia. We studied prospectively 152 adolescents (ages 13-19 yr) undergoing elective surgery. Fifty percent of the patients had nothing by mouth after midnight. ⋯ GV, GpH and subject hunger were unaffected by ingestion of clear fluids. Subject thirst was reduced by clear fluids. It is concluded that unlimited clear fluid ingestion by healthy adolescents up to 3 h before operation decreases thirst and does not affect gastric contents.
-
An interscalene brachial plexus block was performed via a catheter with 20-28 ml of 0.75% bupivacaine plus adrenaline for surgery of the shoulder region in 12 patients. Constant infusion of 0.25% bupivacaine 0.25 mg kg-1 h-1 was continued for 24 h. During surgery light general anaesthesia, without analgesics, was maintained. ⋯ The metabolites DBB and 4-OHB were detectable in plasma from 30 min, with a gradual increase during infusion. At 24 h the mean concentrations of DBB and 4-OHB were 0.33 (0.22) micrograms ml-1 and 0.13 (0.04) micrograms ml-1, respectively. There were no toxic reactions during the blocks.
-
Randomized Controlled Trial Clinical Trial
Hypnotic and anaesthetic action of thiopentone and midazolam alone and in combination.
This study examined the interaction between i.v. administered midazolam and thiopentone on the loss of response to verbal command ("hypnosis") and the loss of response to transcutaneous electrical stimulation of the ulnar nerve ("anaesthesia") in patients presenting for minor elective surgery. Dose-response curves for thiopentone and midazolam individually and in combination were determined using the two end-points in 300 unpremedicated patients. ⋯ Although midazolam failed to produce anaesthesia in the dose range used, the dose of thiopentone required to produce anaesthesia was reduced by 50% in the presence of midazolam. The mechanism of interaction and the potential role of benzodiazepine-barbiturate combinations are discussed and the observed synergistic anaesthesia interaction is used to explain the potentially dangerous combination of benzodiazepines with other potent CNS depressants such as barbiturates and alcohol.