Anaesthesia in the field. Spontaneous ventilation--a new technique

Treatment of status epilepticus with ketamine, are we there yet?

Status epilepticus (SE), a neurological emergency both in adults and in children, could lead to brain damage and even death if untreated. Generalized convulsive SE (GCSE) is the most common and severe form, an example of which is that induced by organophosphorus nerve agents. First- and second-line pharmacotherapies are relatively consensual, but if seizures are still not controlled, there is currently no definitive data to guide the optimal choice of therapy. The medical community seems largely reluctant to use ketamine, a noncompetitive antagonist of the N-methyl-d-aspartate glutamate receptor. However, a review of the literature clearly shows that ketamine possesses, in preclinical studies, antiepileptic properties and provides neuroprotection. Clinical evidences are scarcer and more difficult to analyze, owing to a use in situations of polytherapy. In absence of existing or planned randomized clinical trials, the medical community should make up its mind from well-conducted preclinical studies performed on appropriate models. Although potentially active, ketamine has no real place for the treatment of isolated seizures, better accepted drugs being used. Its best usage should be during GCSE, but not waiting for SE to become totally refractory. Concerns about possible developmental neurotoxicity might limit its pediatric use for refractory SE.

The Ohmeda Universal PAC drawover apparatus. A technical and clinical evaluation

The Ohmeda Universal PAC drawover apparatus, a modification of an earlier series of vapour-specific vaporizers, was assessed with regard to its output under varying gas flows and temperatures and its clinical usage with isoflurane and enflurane. The device tended to over-deliver vapour, particularly at low flows and at high temperatures. Its clinical performance during spontaneous and positive pressure ventilation was satisfactory, although adequate concentrations were not achieved using enflurane in the spontaneous ventilation mode. The device was not assessed with ether or halothane. The robust construction, relatively large capacity and thermocompensation make it suitable for field or military anaesthesia.

Physostigmine in recovery from anaesthesia

Intravenous ketamine anaesthesia has been used by the British army in the field for many years. A recognised problem has been the unpredictable recovery profile this produces. We anaesthetised 28 ASA 1 patients using a standard British military technique. At termination of the anaesthetic, half of the patients were given a physostigmine/glycopyrronium mixture and half were given the equivalent volume of saline 0.9%. There was a significant difference between the two groups with regard to recovery times (p < 0.001). There was no significant difference with regard to other variables. In trauma anaesthesia the improved recovery profile from the use of physostigmine following ketamine anaesthesia may lead to earlier evacuation of the patient.

The use of propofol and alfentanil by infusion in military anaesthesia

A total intravenous technique using propofol and alfentanil was used successfully in four battlefield casualties treated at a British Military Field Hospital during the recent Gulf conflict. All patients made a rapid recovery of adequate quality for prompt evacuation. We believe that the use of propofol and alfentanil as an induction and maintenance regimen for military anaesthesia merits further evaluation and comparison with established techniques.

Flumazenil in ketamine and midazolam anaesthesia

A double-blind, parallel group study using flumazenil and placebo was carried out to determine whether patients who received flumazenil would awake more quickly and whether this drug would reverse the protection conferred by midazolam on the psychic sequelae of ketamine. Fifty female patients were studied. The results showed that there was a significant reduction in awakening time (p = 0.02) and a very significant increase (p = 0.001) in the incidence of dreams in the flumazenil group.