The hospital mortality of patients admitted to the ICU on weekends.

STUDY OBJECTIVES Previous studies have suggested that patients are more likely to die in the hospital if they are admitted on a weekend than on a weekday. This study was conducted to determine whether weekend admission to the ICU increases the risk of dying in the hospital. DESIGN Retrospective cohort study. SETTING ICU of a single tertiary care medical center. PATIENTS A total of 29,084 patients admitted to medical, surgical, and multispecialty ICUs from October 1994 through September 2002. INTERVENTIONS None. MEASUREMENTS AND RESULTS The weekend ICU admissions comprised 27.9% of all ICU admissions (8,108 ICU admissions). The overall hospital mortality rate was 8.2% (2,385 deaths). Weekend ICU admission was associated with a higher unadjusted hospital mortality rate than that for weekday ICU admission (11.3% vs 7.0%, respectively; odds ratio [OR], 1.70; 95% confidence interval [CI], 1.55 to 1.85). In multivariable analyses controlling for the factors associated with mortality such as APACHE (acute physiology and chronic health evaluation) III predicted mortality rate, ICU admission source, and intensity of treatment, no statistically significant difference in hospital mortality was found between weekend and weekday admissions in the overall study population (OR, 1.06; 95% CI, 0.95 to 1.17). For weekend ICU admissions, the observed hospital mortality rates of the medical, multispecialty, and surgical ICUs were 15.2%, 17.2%, and 6.4%, respectively, and for weekday ICU admissions the rates were 16.3%, 10.1%, and 3.5%, respectively. Subgroup analyses showed that weekend ICU admission was associated with higher adjusted hospital mortality rates than was weekday ICU admission in the surgical ICU (OR, 1.23; 95% CI, 1.03 to 1.48), but not in the medical or multispecialty ICUs. CONCLUSIONS The overall adjusted hospital mortality rate of patients admitted to the ICU on a weekend was not higher than that of patients admitted on a weekday. However, weekend ICU admission to the surgical ICU was associated with an increased hospital mortality rate.

[1]  D C Angus,et al.  Caring for the critically ill patient. Current and projected workforce requirements for care of the critically ill and patients with pulmonary disease: can we meet the requirements of an aging population? , 2000, JAMA.

[2]  E. Ivers,et al.  Early Goal-Directed Therapy in the Treatment of Severe Sepsis and Septic Shock , 2001 .

[3]  J. Civetta,et al.  Therapeutic intervention scoring system: a method for quantitative comparison of patient care. , 1974, Critical care medicine.

[4]  P. Pronovost,et al.  Effect of nurse-to-patient ratio in the intensive care unit on pulmonary complications and resource use after hepatectomy. , 2001, American journal of critical care : an official publication, American Association of Critical-Care Nurses.

[5]  J. A. N. Eedleman,et al.  Nurse-Staffing Levels and the Quality of Care in Hospitals , 2002 .

[6]  U. Beckmann,et al.  Problems Associated with Nursing Staff Shortage: An Analysis of the First 3600 Incident Reports Submitted to the Australian Incident Monitoring Study (AIMS-ICU) , 1998, Anaesthesia and intensive care.

[7]  W. Knaus,et al.  The use of risk predictions to identify candidates for intermediate care units. Implications for intensive care utilization and cost. , 1995, Chest.

[8]  J. Birkmeyer,et al.  Potential reduction in mortality rates using an intensivist model to manage intensive care units. , 2000, Effective clinical practice : ECP.

[9]  J. Stechmiller.  The nursing shortage in acute and critical care settings. , 2002, AACN clinical issues.

[10]  E. Halm,et al.  Why do hospital death rates vary? , 2001, The New England journal of medicine.

[11]  Mitchell J Barnett,et al.  Day of the Week of Intensive Care Admission and Patient Outcomes: A Multisite Regional Evaluation , 2002, Medical care.

[12]  J. Pepper,et al.  Difficulties in predicting outcome in cardiac surgery patients. , 1995, Critical care medicine.

[13]  P. Pronovost,et al.  Postoperative complications: does intensive care unit staff nursing make a difference? , 2002, Heart & lung : the journal of critical care.

[14]  Peter J. Pronovost,et al.  Intensive care unit physician staffing is associated with decreased length of stay, hospital cost, and complications after esophageal resection , 2001, Critical care medicine.

[15]  D. Redelmeier,et al.  Mortality among patients admitted to hospitals on weekends as compared with weekdays. , 2001, The New England journal of medicine.

[16]  Peter J Pronovost,et al.  Physician staffing patterns and clinical outcomes in critically ill patients: a systematic review. , 2002, JAMA.

[17]  Ingrid Philibert,et al.  New requirements for resident duty hours. , 2002, JAMA.

[18]  W. Tarnow-Mordi,et al.  Hospital mortality in relation to staff workload: a 4-year study in an adult intensive-care unit , 2000, The Lancet.

[19]  D. R. Jones,et al.  Comparison of POSSUM with APACHE II for prediction of outcome from a surgical high‐dependency unit , 1992, The British journal of surgery.

[20]  F B Rogers,et al.  Predicting survival, length of stay, and cost in the surgical intensive care unit: APACHE II versus ICISS. , 1998, The Journal of trauma.

[21]  R H Brook,et al.  Explaining variations in hospital death rates. Randomness, severity of illness, quality of care. , 1990, JAMA.

[22]  A Comparison of Predictive Outcomes of APACHE II and SAPS II in a Surgical Intensive Care Unit , 2001, American journal of medical quality : the official journal of the American College of Medical Quality.

[23]  K. Rowan,et al.  Variation in intensive care unit outcomes: a search for the evidence on organizational factors , 2001, Current opinion in critical care.

[24]  R. Steinbrook,et al.  The debate over residents' work hours. , 2002, The New England journal of medicine.

[25]  W. Mangold.  Neonatal mortality by the day of the week in the 1974-75 Arkansas live birth cohort. , 1981, American journal of public health.

[26]  D. E. Lawrence,et al.  The Range of Intensive Care Services Today , 1981 .

[27]  R. Hendry.  THE WEEKEND—A DANGEROUS TIME TO BE BORN? , 1981, British journal of obstetrics and gynaecology.

[28]  L. Hydo,et al.  Comparison of APACHE II and III scoring systems for mortality prediction in critical surgical illness. , 1995, Archives of surgery.

[29]  D. Cullen,et al.  Therapeutic Intervention Scoring System: Update 1983 , 1983, Critical care medicine.

[30]  W. Knaus,et al.  The APACHE III prognostic system. Risk prediction of hospital mortality for critically ill hospitalized adults. , 1991, Chest.