Circadian pattern of intubation rates in ED patients with congestive heart failure.
OBJECTIVE
A previous study showed that pulmonary edema patients presenting between noon and 4 pm have the highest rates of myocardial infarction and death. We hypothesized that the highest intubation rates would also occur at these times.


METHODS
We performed a retrospective cohort study of consecutive patients seen by emergency department physicians in 15 hospital emergency departments (1996-2003).


RESULTS
Of 3.6 million visits in the database, 39,795 (1.1%) patients had congestive heart failure. We found statistically significant circadian variations in intubation rates. Patients arriving between midnight and 4 am had the highest intubation rates (4.1%), and those arriving between noon and 4 pm had the lowest (1.2%) (difference, 2.9%; 95% confidence interval, 2.4%-3.4%; P < .0001).


CONCLUSIONS
We found significant circadian variation in intubation rates, with a marked increase around midnight. Pathological mechanisms causing patients with congestive heart failure to require intubation may differ from those resulting in myocardial infarction or death.
Allegra
John R
JR
Morristown Memorial Hospital Residency in Emergency Medicine, Morristown, NJ 07962, USA. johnalle@verizon.net
Eskin
Barnet
B
Kleinberg
Jeffery
J
Cochrane
Dennis G
DG
D000368:Aged; D002940:Circadian Rhythm; D004630:Emergencies; D005260:Female; D006333:Heart Failure / Q000453:epidemiology* / Q000628:therapy*; D006801:Humans; D015994:Incidence; D007442:Intubation, Intratracheal; D008297:Male; D009515:New Jersey / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors