Critical care medicine
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Several recent articles have suggested the use of mean airway pressure (Paw) as an index of the physiological effect of ventilating pressures. To facilitate the understanding of this parameter, operational formulas are derived by applying the explicit, mathematical definition of Paw to several clinically relevant pressure waveforms. These formulas are then generalized to apply to any wave shape. It is shown that any pressure waveform can be characterized by a waveform constant K, knowledge of which permits the estimation of Paw using information from either airway pressure recordings or the control settings and pressure gauges on conventional ventilators.
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Critical care medicine · Jun 1982
Elective cricothyroidotomy: a clinical and histopathological study.
Elective cricothyroidotomy was carried out on 61 adult patients in the ICU between June 1977 and October 1980. This procedure replaced elective tracheotomy in those patients who were judged to require respirator treatment for a period longer than 72 h. Twenty-six of the patients were examined by the ENT department. ⋯ Contraindications to cricothyroidotomy are endotracheal intubation for a period longer than 72 h, respiratory difficulties after previous endotracheal intubation, and acute infections of the larynx. Cricothyroidotomy is faster and much easier than tracheotomy. The authors believe that every doctor who works in intensive care should be able to carry out this procedure.