A study of intracuff pressure measurements, trends and behaviour in patients during prolonged periods of tracheal intubation

Intracuff pressure (c.p.) was measured continuously in 12 patients during prolonged periods of tracheal intubation. High residual volume--low pressure (floppy) and low residual volume--high pressure (conventional) cuffs were studied. The mean baseline c.p. at minimal occluding pressure was significantly smaller in floppy cuffs than in conventional cuffs. With coughing, the peak pressures in both cuff types were much greater than the baseline pressures but did not differ significantly from each other. On the basis of our observations, we recommend a simplification of the test methods for cuffs and tube collapse. We believe universal testing to 300 mm Hg (40 kPa) to be reasonable and to incorporate a realistic safety factor. Intracuff pressure tends to diminish with time, but there is a poor correlation between the rate of pressure decrease and elapsed time. As this decrease is not accurately predictable, gas should be added to the cuff as required, rather than at intervals. Other features of cuff behaviour are discussed and suggestions made to explain some anomalies occasionally observed in the cuff pressure behaviour pattern.

Agent-specific filling devices. An evaluation of two prototypes

Two prototype agent-specific devices have been tested and neither in its present form is ideal. Filling of vaporisers may be delegated to inexperienced persons but the devices tested do not ensure that vaporisers can only be filled with the correct agent. Significant atmospheric pollution with the volatile anaesthetic agent may occur at the time of filling. At present, the devices are limited to three agents, enflurane, halothane and methoxyflurane.

A simplified technique for cannulation of the jugular bulb

A method of jugular bulb cannulation is discussed which is quick and easy to perform, ensures accurate placement of the catheter tip and causes minimal discomfort to the patient. Advantages of this technique are discussed.

Disturbances of pulmonary function in patients with fat embolism

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