The impact of a "low-intensity" versus "high-intensity" medical intensive care unit on patient outcomes in critically ill veterans.
OBJECTIVE
To determine whether a low-intensity versus high-intensity medical intensive care unit (MICU) format in a Veterans Affairs (VA) hospital setting improves patient outcomes, as measured by duration of mechanical ventilation (MV), ventilator-free days (VFDs), and hospital mortality.


METHODS
Retrospective cohort study.


METHODS
Medical intensive care unit at the San Francisco Veterans Affairs Medical Center (SFVAMC).


METHODS
On July 1, 2004, the SFVAMC transitioned from a low-intensity MICU to a high-intensity MICU. All patients admitted to the MICU who required MV for 18 months before (n = 96) and 18 months after (n = 131) the transition were included in the analysis.


METHODS
We prospectively defined the primary outcome measure as the difference in the median duration of MV between groups. Secondary outcomes included VFDs and hospital mortality. Continuous variables were compared using the Wilcoxon rank sum test; dichotomous variables were compared using Fisher exact test.


RESULTS
The low-intensity and high-intensity MICU groups were similar in age, gender, weight, and admitting diagnosis (P > .27 in all cases). Acute Physiology and Chronic Health Evaluation II (APACHE II) scores were 22.0 in the low-intensity era and 20.0 in the high-intensity era (P = .048). Median duration of MV was significantly lower in the high-intensity MICU format compared to the low-intensity MICU format (102 vs 61 hours, P for log-rank test = .0052). After controlling for covariates, there were 4.2 more VFDs in the high-intensity era (95% CI 1.9 to 6.6 days). The high-intensity era was associated with a reduced hospital mortality rate (27% vs 40%) and an adjusted odds ratio of 0.34 (95% CI 0.15 to 0.74).


CONCLUSIONS
For critically ill veterans admitted to an MICU requiring MV, a high-intensity ICU structure is associated with more favorable mechanical ventilatory outcomes and lower mortality.
Singer
Jonathan P
JP
Division of Pulmonary/Critical Care Medicine, UC San Francisco, CA 94143, USA. jon.singer@ucsf.edu
Kohlwes
Jeffrey
J
Bent
Stephen
S
Zimmerman
Leslie
L
Eisner
Mark D
MD
D000368:Aged; D003422:Critical Care / Q000379:methods*; D016638:Critical Illness / Q000628:therapy*; D005260:Female; D017052:Hospital Mortality; D006787:Hospitals, Veterans; D006801:Humans; D007362:Intensive Care Units; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D012495:San Francisco; D016896:Treatment Outcome; D014728:Veterans
N Engl J Med. 2001 Nov 8;345(19):1368-77
11794169
N Engl J Med. 2000 May 4;342(18):1301-8
10793162
J Neurosurg Anesthesiol. 2001 Apr;13(2):83-92
11294463
Crit Care Med. 2002 Aug;30(8):1772-7
12163791
Chest. 1989 Jul;96(1):127-9
2736969
JAMA. 1996 Jul 24-31;276(4):322-8
8656546
JAMA. 2000 Dec 6;284(21):2762-70
11105183
Crit Care Med. 2001 Mar;29(3):635-40
11373434
N Engl J Med. 2000 May 18;342(20):1471-7
10816184
Ann Surg. 1999 Feb;229(2):163-71
10024095
Crit Care Med. 2001 Oct;29(10):1853-9
11588439
Crit Care Med. 2001 Apr;29(4):753-8
11373463
J Crit Care. 2004 Sep;19(3):158-64
15484176
Am J Respir Crit Care Med. 1998 May;157(5 Pt 1):1468-73
9603125
JAMA. 2002 Nov 6;288(17):2151-62
12413375
N Engl J Med. 2001 Nov 8;345(19):1359-67
11794168
Crit Care Med. 1990 Nov;18(11):1282-6
2225900
Ann Intern Med. 2008 Jun 3;148(11):801-9
18519926
Eff Clin Pract. 2000 Nov-Dec;3(6):313-6
11151534
Am J Respir Crit Care Med. 2000 Jul;162(1):191-6
10903628
Ann Intern Med. 2004 Mar 2;140(5):338-45
14996675
Am J Respir Crit Care Med. 2007 Oct 1;176(7):685-90
17556721
Crit Care Med. 1985 Oct;13(10):818-29
3928249
N Engl J Med. 1995 Feb 9;332(6):345-50
7823995
Crit Care Med. 2004 Jun;32(6):1254-9
15187502
JAMA. 1999 Apr 14;281(14):1310-7
10208147
N Engl J Med. 2002 Feb 21;346(8):549-56
11856793
Crit Care Med. 2006 Apr;34(4):1016-24
16505703
Intensive Care Med. 2001 May;27(5):865-72
11430543
Crit Care Med. 2004 Nov;32(11):2311-7
15640647