A N E S T H E S I A

FLAXEDIL FOR EAR, NOSE AND THROAT SURGERY IN ADULTS.

BY BERYL HARRISON, D.A., M.R.C.S., L.R.C.P. \. ISITING ANfiSTHETIST, AMERSHAM GENERAL A N D HIGH WYCOMBE MEMORIAL HOSPITALS

FLAXEDIL, Tri-(p-diethy1aminoethoxy)-benzene triethiodide, is a synthetic compound having a curarising action which interferes with nerve impulses at the myoneural junction. The aqueous solution is stable, and compatible with solutions of thiopentone sodium. The paralysing action of flaxedil, like d-tubocurarine, can be neutralised by anticholinesterases such as neostigmine.

Flaxedil is supplied in glass ampoules of a 4 per cent. solution in two sizes, containing 80 mg. in 2 c.cm., and 120 mg. in 3 c.cm.

Maximum relaxation occurs in about ninety seconds after intra- venous injection, and continues on the average for twenty minutes. In the writer’s opinion, 80 mg. flaxedil has about the same effect as 12 mg. of tubocurarine.

Respiration appears to be depressed to a lesser degree than by the equivalent dose of tubocurarine, and this depression wears off much more rapidly than with the latter drug. The writer has found flaxedil an extremely useful adjuvant to general anaesthesia for Ear, Nose, and Throat surgery in adults.

Advantages. (1) It is miscible with sodium thiopentone, so that one intravenous injection only is required.

(2) Relaxation of the jaw is excellent, permitting of an easy and leisurely intubation under direct vision with complete absence of spasm almost immediately after the initial injection.

(3) A light plane of anasthesia is all that is necessary, nitrous oxide and oxygen being sufficient for the average case.

(4) The patient is ready for operation in a very short space of time, a considerable advantage with a lengthy list.

(5) With suitable dosage recovery is rapid, the reflexes returning as soon as the operation is completed with respirations of normal amplitude.

Disadvantages. As, at the time of writing, only a comparatively small series of cases has been conducted with flaxedil, it is unwise to be dogmatic, but it would appear that bleeding during operation is slightly increased.

Technique for the Average Patient (1) 1Q hours pre-operatively omnopon 3 gr. and scopolamine

I / 150 gr. by hypodermic injection is given. (2) 80 mgm. of flaxedil and 0.5 gm. of thiopentone is injected

slowly intravenously from the same syringe. (3) The lungs are inflated once or twice with 100 per cent. oxygen. (4) Nasal or oral intubation is then easily performed under

direct vision, the endotracheal tube having been previously lubricated with 1 per cent. nupercaine ointment.

(5) Maintenance can usually be continued satisfactorily with nitrous oxide and oxygen, supplemented by minimal trilene or other agents if required.

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A N K S T H E S I A

Flaxedil combined with thiopentone has been found particularly suitable for bronchoscopies and gastroscopies. Using the dosage mentioned above for the average case, relaxation is excellent, there is complete absence of spasm, and recovery is rapid. Contra-indications. As with tubocurarine, myasthenia gravis is

a complete contra-indication to the use of flaxedil, and facilities for providing an effective airway and adequate oxygenation are essential.

ABSTRACTS FROM CURRENT LITERATURE

ANASTHESIA IN THORACIC SURGERY By H. J. SHIELDS. C.M.A.J. 1947. 56. March. 287.

1~ many respects the problems of the anasthetist in thoracic surgery are more complex than those facing the surgeon, and in the opinion of the author many of these problems remain unsolved. The margin of safety is small and the sudden occurrence of complications which may impair respiratory function may transform in a few minutes a patient hitherto in good condition into one verging on a state of respiratory collapse.

In wet cases prolonged pre-operative postural drainage is advis- able. Depression of respiration by premedicating drugs must be avoided. Anasthesia by means of ether, either alone or in com- bination with cyclopropane, will usually be found most satisfactory. Oral intubation and closed carbon dioxide absorption technique enable controlled respiration with positive pressure to be carried out. In general, the author does not advocate the use of a cuffed tube, although Magill’s technique of endobronchial intubation and the use of a suction catheter equipped with an inflatable cuff-is found of value in many instances.

Care must be taken to keep the patient well oxygenated and to prevent carbon dioxide accumulation, while anasthesia deep enough to prevent reflex disturbance is essential. Suction must be applied sufficiently vigorously to prevent the lungs becoming moist and especially to remove all secretions expressed from the collapsing lung. (Complete obliteration of the cough reflex is not recommended, as often following a simple coughing effort sputum is projected into the bronchi or trachea.) The operation should be halted at short intervals to permit the anasthetist to inflate the collapsed lung momentarily to prevent it becoming edematous. Bronchoscopic drainage may in some cases be necessary at the end of the operation to prevent collapse of the lung.

In thoracic surge:y demands greater than usual are made upon the skill and patience of the anasthetist. The main problem is that of maintaining adequate pulmonary function in the presence of a vital capacity seriously impaired by disease and by the operative manipulations: The operations are long and produce considerable shock. In few other procedures does the anzesthetist bear so great a share in determining the success or failure of the surgical effort.

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