Patient responses during rapid terminal weaning from mechanical ventilation: A prospective study

Objective: To describe and analyze patient responses to rapid terminal wean ing from mechanical ventilation. Design: A prospective, descriptive, correlational study, Setting: An urban, university-affiliated, trauma/emergency hospital. Patients: A convenience sample of 31 adult patients experiencing withdrawal of mechanical ventilation. Interventions: None. Measurements and Main Results: Physiologic (peripheral oxy gen saturation, end-tidal CO2, heart rate, and respiratory rate) and comfort (electroenceph alogram [EEG], Bizek Agitation Scale, and the COMFORT scale) measures were collected at baseline, during, and after the terminal weaning procedure. Cl inical status was measured using the Acute Physiology and Chronic Health Ev aluation score, Glasgow Coma Scale, and PaO2/FIO2. Duration of survival aft er the wean inversely correlated with illness severity but did not correlat e with consciousness, use of analgesia/sedation, or pulmonary function. Res piratory rate and oxygen saturation changed significantly during the wean b ut not end tidal CO2. Patients remained comfortable with little or no analg esia/sedation, in a predominantly comatose sample. Subjective measures of c omfort strongly correlated with objective data from bispectral analysis of EEG. Conclusions: Patients with altered consciousness or coma can be kept comfor table during a rapid terminal weaning procedure with morphine and benzodiaz epines in low doses. Comfort can be reliably evaluated using subjective sca les.