Canadian journal of anaesthesia = Journal canadien d'anesthésie
-
Randomized Controlled Trial Clinical Trial
Prevention of epidural morphine-induced respiratory depression with intravenous nalbuphine infusion in post-thoracotomy patients.
The efficacy of nalbuphine, an agonist/antagonist opioid, in preventing respiratory depression from epidural morphine analgesia after thoracotomy, was assessed in a randomized double-blind placebo controlled trial. After a standardized general anaesthetic and 0.15 mg.kg-1 of epidural morphine, patients received a bolus and then a 24 h infusion of nalbuphine (200 micrograms.kg-1 + 50 micrograms.kg-1.hr-1, 100 micrograms.kg-1 + 25 micrograms.kg-1.hr-1, or 50 micrograms.kg-1 + 12.5 micrograms.kg-1.hr-1) or placebo. ⋯ A 200 micrograms.kg-1 bolus of nalbuphine followed by a 50 micrograms.kg-1.hr-1 infusion achieved a mean steady state blood level of 38.2 ng.ml-1 and prevented CO2 retention greater than 50 mmHg in all but two patients, neither of whom required naloxone. There was no difference in the incidence of side effects among groups, and analgesia appeared to be unaffected by nalbuphine.
-
Comparative Study
Comparison of end-tidal carbon dioxide, oxygen saturation and clinical signs for the detection of oesophageal intubation.
The reliability of various methods for detecting oesophageal intubation was assessed by means of a single blind study in rats. Both oesophagus and trachea were simultaneously intubated. The presence or absence of various clinical signs was noted during tracheal or oesophageal ventilation and arterial blood gases and end-tidal CO2 were measured. ⋯ Moisture condensation in the tracheal tube (PPV = 1.0) and abdominal distension (PPV = 0.9) were judged to be the least reliable because each had a high false negative rate of 0.3. The most reliable method for the early detection of oesophageal intubation in rats was end-tidal, CO2 (sensitivity 1.0, specificity = 1.0, PPV = 1.0). In addition, end-tidal CO2 when used in conjunction with the four clinical signs improved the reliability of these signs.
-
Clinical Trial Controlled Clinical Trial
Decreasing the toxic potential of intravenous regional anaesthesia.
In an attempt to reduce the dose of local anaesthetic agent during intravenous regional anaesthesia (IVRA) of the upper limb, we have used a forearm tourniquet in 12 adult volunteers. The volume of the forearm venous system was predetermined angiographically. We performed IVRA with three solutions of lidocaine (0.25, 0.375, 0.5 per cent) administered in a volume equal to the forearm venous system. ⋯ With this technique, lidocaine 0.5 per cent resulted in a dose of 1.5 mg.kg-1 and provided excellent analgesia. Lower concentrations were unsatisfactory. We conclude that the use of a forearm tourniquet allows reduction of the local anaesthetic dose to a non-toxic level and thus increases the safety of IVRA.
-
We report a case of suspected carbon dioxide embolism occurring during laparoscopy. Among the sequelae was neurological dysfunction felt to be secondary to paradoxical embolization. The patient was treated with hyperbaric oxygen therapy. Hyperbaric oxygen should be considered when confronted with a clinically important gas embolism.