Effect of prior administration of a non-depolarising muscle relaxant on the action of suxamethonium in the dog.

The non-depolarising muscle relaxants alcuronium (0.1 mg kg-1), gallamine (1 mg kg-1) and pancuronium (0.06 mg kg-1) were administered to six dogs. At 50 per cent return of neuromuscular activity, as measured by the train-of-four technique, the depolarising muscle relaxant suxamethonium (0.3 mg kg-1) was injected intravenously. At 50 per cent return of neuromuscular activity, atropine and neostigmine were administered to reverse the neuromuscular block. The duration of action of suxamethonium was reduced by each of the non-depolarising muscle relaxants.

Anaesthetic management of baboons undergoing heterotopic porcine cardiac xenotransplantation.

A detailed anaesthetic technique for baboons (Papio anubis) undergoing heterotopic abdominal cardiac xenotransplantation is described. Twenty-two baboons served as transplant recipients. Donors were either crossbred farm pigs (Sus scrofa) (n = 4) or transgenic pigs (Sus scroefa) (n = 18) expressing human complement regulatory proteins on the endothelium. Intra-operative management was complicated by the physiological consequences of infrarenal. abdominal aortic cross-clamping, in addition to the immunological sequelae related to cross-species transplantation. In choosing anaesthetics for this procedure, we considered the need for maximal cardiac stability throughout a long surgical procedure that required abdominal aortic cross-clamping to facilitate the implantation of an oversized porcine cardiac graft. Baboons received a balanced anaesthetic consisting of inhaled isoflurane in oxygen, intravenous fentanyl and intravenous pancuronium. The pharmacological techniques employed were found to be safe and reliable and were well tolerated by our recipients without any significant side-effects.

The effect of low dose rocuronium on globe position, muscle relaxation and ventilation in dogs: a clinical study.

OBJECTIVE: The purpose of this study was to evaluate globe position, muscle relaxation and changes in ventilatory parameters after intravenous administration of 0.1 mg/kg rocuronium. STUDY DESIGN: Prospective clinical study. ANIMAL STUDIED: Sixteen dogs of different breeds, with a body weight of 22.1 +/- 13 kg and age of 5.6 +/- 2.8 years (mean +/- SD), were anesthetized for a short ophthalmic examination requiring central position of the globe. PROCEDURES: All dogs were premedicated with 0.005 mg/kg medetomidine and 0.1 mg/kg methadone IV. Anesthesia was induced with propofol to effect and maintained with 10 mg/kg/h propofol by continuous rate infusion. Following endotracheal intubation all dogs breathed 100% oxygen via an anesthetic circle system. Neuromuscular function was assessed with an acceleromyograph (TOF-Guard, Organon Teknika NV, Turnhout, Belgium) and by stimulation of the nervus peroneus superficialis. The ventilation parameters were measured using spirometry and capnography. After baseline measurements 0.1 mg/kg rocuronium was administered IV. Minute volume (MV), tidal volume (Vt), respiratory rate (RR), end expiratory carbon dioxide concentration (PE'CO(2)) and maximal depression of the response of the first twitch (T1) of train-of-four (TOF) stimulation and train-of-four ratio (TOFR) was measured. The change in the position of the globe was recorded. RESULTS: T1 decreased to 61 +/- 18% and the TOF ratio to 45 +/- 21% of baseline values. Both parameters returned to baseline after 9 min. There was no significant reduction in MV, TV and RR and no increase in PE'CO(2). The globe rotated to a central position of 45 +/- 7.7 s after administration of rocuronium and remained there for 23 +/- 10.8 min in all dogs. CONCLUSION: Rocuronium administered intravenously at a dose of 0.1 mg/kg to dogs causes a central position of the globe but minimal impairment of ventilation parameters.

Anatomic and anesthetic considerations in experimental cardiopulmonary surgery in swine.

We have used immature commercial swine (13-25 kg) successfully in a variety of experimental cardiopulmonary surgical procedures in our laboratories since 1981. Multiple drug anesthetic protocols using barbiturates, narcotics, paralytic and antiarrhythmic agents have been employed in over 400 procedures per year. Complications, including fatal cardiac arrhythmias, have been greatly reduced by anesthetic protocols and surgical procedures developed through experience.