British journal of anaesthesia
-
Randomized Controlled Trial Clinical Trial
Alkalinization of local anaesthetic for intra-articular instillation during arthroscopy.
Intra-articular instillation of a local anaesthetic agent for pain relief after arthroscopy has not been shown consistently to be beneficial. Alkalinization of a local anaesthetic agent may be expected to improve onset time, quality and duration of the block. ⋯ There were no differences in any of these measurements at any time between the groups, except that the group which received intraarticular saline had significantly lower pain scores 8 h after operation than the groups which had alkalinized or plain prilocaine. We conclude that prilocaine, at both pH values, is ineffective in producing postoperative analgesia but as there were patients who received no analgesic agents and who had very little pain, we may also conclude that arthroscopy is not a consistently painful procedure and is not a good model for assessing the efficacy of local anaesthetic agents.
-
We have assessed the effect of lengthening the expiratory limb of an Ayre's T-piece from 0.5 to 10 m for ventilation with a Nuffield series 200 ventilator and Newton valve, as this equipment is potentially suitable for infants and young children during anaesthesia for magnetic resonance imaging (MRI). We used lung models with compliances and resistances representative of the respiratory system with intubated trachea of a neonate, infant and child weighing 15-20 kg. The effects on ventilation were small, being greatest with the largest lung model where the longer T-piece resulted in a reduction in tidal volume from 261 to 236 ml and an increase in intrinsic and extrinsic positive end-expiratory pressure from 0.20 to 0.32 kPa and from 0.14 to 0.25 kPa, respectively. Such changes are unlikely to be clinically important and can be obviated by using the ventilator with the standard valve in children weighing 15-20 kg.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Effect of nabilone on nausea and vomiting after total abdominal hysterectomy.
In a prospective, double-blind study, we have examined the effect of preoperative nabilone on postoperative nausea and vomiting (PONV). Sixty women, less than 70 yr old, undergoing total abdominal hysterectomy, were allocated randomly to receive either nabilone 2 mg or metoclopramide 10 mg orally 90 min before induction of anaesthesia. ⋯ Data from 53 patients were analysed: the incidences of nausea and vomiting for the metoclopramide group were 70% and 67%, respectively; the corresponding values for the nabilone group were 73% and 54%. These differences were not significant.
-
Randomized Controlled Trial Clinical Trial
Multimodal analgesia before thoracic surgery does not reduce postoperative pain.
Several reports have suggested that preoperative nociceptive block may reduce postoperative pain, analgesic requirements, or both, beyond the anticipated duration of action of the analgesic agents. We have investigated, in a double-blind, placebo-controlled study, pre-emptive analgesia and the respiratory effects of preoperative administration of a multimodal antinociceptive regimen. Thirty patients undergoing thoracotomy were allocated randomly to two groups. ⋯ There were no differences between the groups in postoperative VAS scores (at rest or after movement), PaCO2 values or postoperative spirometry. However, pain thresholds to pressure applied at the side of the chest contralateral to the site of incision decreased significantly from preoperative values on days 1 and 2 after surgery in both groups. The results of this study do not support the preoperative use of this combined regimen for post-thoracotomy pain.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Prevention of hypothermia during hip surgery: effect of passive compared with active skin surface warming.
We have measured aural canal (core) and skin temperatures, and body heat content in 45 patients undergoing elective hip arthroplasty. They received general anaesthesia which included thiopentone, vecuronium and enflurane and nitrous oxide in oxygen. ⋯ Core temperature and mean body heat content decreased significantly during surgery in groups 1 and 2 (aural canal temperature 1.5 and 1.0 degrees C, and mean body heat content 287 and 189 kJ, respectively), while in group 3 these variables remained near preoperative values (P = 0.001). Mean skin and hand temperatures decreased in the control group, increased in the active warming group and were unchanged in the passive warming group (P < 0.005), indicating that the forced heated air system was very efficient in providing thermal homeostasis during surgery, while the metallized plastic sheet was able to insulate the skin only from radiant and convective heat losses, without attenuating the reduction in core temperature.