Ml. Campbell et al., Patient responses during rapid terminal weaning from mechanical ventilation: A prospective study, CRIT CARE M, 27(1), 1999, pp. 73-77
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.