Acute and long-term survival in chronically critically ill surgical patients: a retrospective observational study

Abstract

Introduction: Various cohort studies have shown that acute (short-term) mortality rates in unselected critically ill patients may have improved during the past 15 years. Whether these benefits also affect acute and long-term prognosis in chronically critically ill patients is unclear, as are determinants relevant to prognosis.

Methods: We conducted a retrospective analysis of data collected from March 1993 to February 2005. A cohort of 390 consecutive surgical patients requiring intensive care therapy for more than 28 days was analyzed.

Results: The intensive care unit (ICU) survival rate was 53.6%. Survival rates at one, three and five years were 61.8%, 44.7% and 37.0% among ICU survivors. After adjustment for relevant covariates, acute and long-term survival rates did not differ significantly between 1993 to 1999 and 1999 to 2005 intervals. Acute prognosis was determined by disease severity during ICU stay and by primary diagnosis. However, only the latter was independently associated with long-term prognosis. Advanced age was an independent prognostic determinant of poor short-term and long-term survival.

Conclusion: Acute and long-term prognosis in chronically critically ill surgical patients has remained unchanged throughout the past 12 years. After successful surgical intervention and intensive care, long-term outcome is reasonably good and is mainly determined by age and underlying disease.

Figure 1

Patient flow after inclusion in the study. LTCU, long-term care unit; NICU, neurological intensive care unit; SICU, surgical intensive care unit.

Figure 2

Twelve-year survival: chronically critically ill patients who have already survived 150 days versus general population. Presented are Kaplan-Meier plots showing 12-year survival rates (after inclusion) in patients surviving more than 150 days (dashed line) and in the German general population (continuous line; reference age 61 years; data from Statistisches Bundesamt Wiesbaden, Germany [30]).

Figure 3

Twelve-year survival: patients who have already survived longer than five years versus general population. Presented are Kaplan-Meier plots showing 12-year survival rates (after inclusion) in patients having already survived for more than five years (dashed line) and in the German general population (continuous line; data from Statistisches Bundesamt Wiesbaden, Germany [30]). P < 0.001 versus reference population of 1,000 individuals

Figure 4

Univariate analysis of surgical efficacy versus cumulative hazard rate: first 150 days after inclusion. Shown is the univariate association between the number of surgical revisions (mean value per quartile) and the corresponding cumulative hazard rate for the first 150 days after inclusion. P < 0.001 after quadratic transformation of continuous data, and addition of a time-dependent covariate.

Figure 5

Univariate analysis of surgical efficacy versus cumulative hazard rate: first two years after inclusion. Univariate association between the number of surgical revisions (mean value per quartile) and the corresponding cumulative hazard rate for the first two years after inclusion in patients surviving more than 150 days. P = 0.033 after quadratic transformation of continuous data.