22 Aug 12
By DJ Wallace, DC Angus, AE Barnato, AA Kramer, JM Kahn
N Engl J Med. 2012;366:2093-2101
Hospitals are increasingly adopting 24-hour intensivist physician staffing as a strategy to improve intensive care unit (ICU) outcomes. However, the degree to which nighttime intensivists are associated with improvements in the quality of ICU care is unknown.
We conducted a retrospective cohort study involving ICUs that participated in the Acute Physiology and Chronic Health Evaluation (APACHE) clinical information system from 2009 through 2010, linking a survey of ICU staffing practices with patient-level outcomes data from adult ICU admissions. Multivariate models were used to assess the relationship between nighttime intensivist staffing and in-hospital mortality among ICU patients, with adjustment for daytime intensivist staffing, severity of illness, and case mix. We conducted a confirmatory analysis in a second, population-based cohort of hospitals in Pennsylvania from which less detailed data were available.
The analysis with the use of the APACHE database included 65,752 patients admitted to 49 ICUs in 25 hospitals. In ICUs with low-intensity daytime staffing, nighttime intensivist staffing was associated with a reduction in risk-adjusted in-hospital mortality (adjusted odds ratio for death, 0.62; P=0.04). Among ICUs with high-intensity daytime staffing, nighttime intensivist staffing conferred no benefit with respect to risk-adjusted in-hospital mortality (odds ratio, 1.08; P=0.78). In the verification cohort, there was a similar relationship among daytime staffing, nighttime staffing, and in-hospital mortality. The interaction between nighttime staffing and daytime staffing was not significant (P=0.18), yet the direction of the findings were similar to those in the APACHE cohort.
The addition of nighttime intensivist staffing to a low-intensity daytime staffing model was associated with reduced mortality. However, a reduction in mortality was not seen in ICUs with high-intensity daytime staffing.
23 Mar 12
By H T Stelfox,B R Hemmelgarn, S M Bagshaw, S Gao, C J Doig, C Nijssen-Jordan, B Manns
Arch Int Med 2012;172:467-474
Intensive care unit (ICU) beds, a scarce resource, may require prioritization of admissions when demand exceeds supply. We evaluated the effect of ICU bed availability on processes and outcomes of care for hospitalized patients with sudden clinical deterioration.
We identified consecutive hospitalized adults in Calgary, Alberta, Canada, with sudden clinical deterioration triggering medical emergency team activation between January 1, 2007, and December 31, 2009. We compared ICU admission rates (within 2 hours of medical emergency team activation), patient goals of care (resuscitative, medical, and comfort), and hospital mortality according to the number of ICU beds available (0, 1, 2, or >2), adjusting for patient, physician, and hospital characteristics (using data from clinical and administrative databases).
The cohort consisted of 3494 patients. Reduced ICU bed availability was associated with a decreased likelihood of patient admission within 2 hours of medical emergency team activation (P = .03) and with an increased likelihood of change in patient goals of care (P < .01). Patients with sudden clinical deterioration when zero ICU beds were available were 33.0% (95% CI, –5.1% to 57.3%) less likely to be admitted to the ICU and 89.6% (95% CI, 24.9% to 188.0%) more likely to have their goals of care changed compared with when more than 2 ICU beds were available. Hospital mortality did not vary significantly by ICU bed availability (P = .82).
Among hospitalized patients with sudden clinical deterioration, we noted a significant association between the number of ICU beds available and ICU admission and patient goals of care but not hospital mortality.
15 Jan 10
By J-L Vincent, S Opal and J Marshall
Crit Care Med 2010;38:283-287
Severity scores such as Acute Physiology and Chronic Health Evaluation II have been advocated as entry criteria for clinical trials and in clinical decision-making. We present ten reasons why we believe this approach is not appropriate and may even be detrimental.
Available relevant literature from authors’ personal databases and personal knowledge of past and future clinical trial development.
Severity scores were not designed for use in individual patients or for therapeutic decision-making for specific interventions. Difficulties with the time window needed to calculate these scores and the need to administer therapies early further limit their use in this context. The complex nature of the scores makes it difficult to use them at the bedside and there is considerable interobserver variability in score calculation. Inclusion of chronic health and age points in severity scores may prevent younger, previously healthy patients, with similar acute physiological dysfunction and therefore total lower severity scores, from trial inclusion or from receiving therapies that may be beneficial.
We believe severity of illness scores are poor surrogates for risk stratification and should not be used as a criterion for patient enrollment into clinical trials or as the basis for individual treatment decisions.
09 Aug 09
By T Iwashyna, A Kramer, J Kahn
Critical Care Medicine 2009;37:1545-1557
Although intensive care units (ICUs) with higher overall patient volume may achieve better outcomes than lower volume ICUs, there are few data on the effects of increasing patient loads on patients within the ICU.
To examine the association of ICU occupancy with the patient outcomes within the same ICU.
We examined 200,499 patients in 108 ICUs using the Acute Physiology and Chronic Health Evaluation IV database in 2002-2005. Daily census on the day of admission was determined for each patient and defined in relation to the mean census. We used conditional logistic regression to compare inpatient outcomes of patients admitted on high census days to those admitted in the same ICU on low census days. We controlled for severity of illness at the patient level using data on clinical, demographic, and physiologic variables on admission to the ICU.
Measurements and main results
Patients admitted on high census days had the same odds of inpatient mortality or transfer to another hospital as patients admitted on average or on low census days. These findings were robust to multiple alternative definitions of day of admission census and were confirmed in several subgroup analyses.
The ICUs in this data are able to function as high reliability organizations. They are able to scale up their operations to meet the needs of a wide range of operating conditions while maintaining consistent patient mortality outcomes.