Study objectives: To describe the prognostic factors,
clinical course, and outcome of patients with status asthmaticus
treated in a medical ICU (MICU).
Design: Analysis of
Setting: A multidisciplinary MICU of
an inner-city university hospital.
collected data on 132 hospital admissions of 89 patients with status
asthmaticus treated in our MICU from August 1995 through July
Measurements: APACHE (acute physiology and
chronic health evaluation) II scores were among the parameters
Results: Seventy-nine percent of the
patients were female, and 67% were African American (mean ± SD age,
42.4 ± 15.1 years). Patients in 48 of the 132 hospital
admissions (36%) required invasive mechanical ventilation; sepsis
developed in patients during 17 hospital admissions (13%),
nonpulmonary organ failure developed during 16 hospital admissions
(12%), and ARDS developed during 2 hospital admissions (2%).
Pneumothorax developed in four patients and required tube thoracostomy
in all four patients. The median APACHE II score was 11. Predicted
mortality and actual mortality were 6.7% and 8.3%, respectively. The
two most common immediate causes of death were pneumothorax (n = 3)
and nosocomial infection (n = 3). All the deaths occurred in female
patients. Compared with survivors, nonsurvivors had higher APACHE II
scores (median, 26 vs 15; p < 0.0001), Paco2
(63.8 ± 21.3 mm Hg vs 47.8 ± 19.1 mm Hg, p = 0.0101), and lower
arterial pH (7.09 ± 0.12 vs 7.27 ± 0.12, p < 0.0001),
respectively. Patients in 10 of 48 hospital admissions (21%) who
required mechanical ventilation died.
Conclusions: The hospital mortality of patients admitted to
an MICU for status asthmaticus is higher than expected. Higher APACHE
II score and Paco2 and lower arterial pH within
24 h of hospital admission are associated with increased
mortality. Sepsis and nonpulmonary organ failure are more likely to
develop in nonsurvivors than survivors.