The Association Between Pressure Ulcer/Injury Development and Short-term Mortality in Critically Ill Patients: A Retrospective Cohort Study.

UNLABELLED

Pressure ulcers/injuries (PU/Is) affect the social, mental, and physical well-being of patients; increase treatment costs; prolong hospital stays; increase patient risk for infections; and may independently decrease life expectancy.

PURPOSE

The aim of this retrospective study was to examine the association between PU/I development and mortality in a large cohort of consecutively admitted critically ill patients.

METHODS

Data from adult patients ( >18 years of age) admitted to an intensive care unit (ICU) between 2010 and 2013 were extracted from the ICU electronic clinical information system. Patients were excluded if they had a PU/I present on admission, no recorded admission modified Jackson/Cubbin (mJ/C) or Sequential Organ Failure Assessment (SOFA) score, or their ICU outcome was undetermined. The mJ/C risk scale (score range 9-48) was used to assess the PU/I risk (the lower the score, the higher the PU/I risk), the SOFA score (score range 0-24; the higher the SOFA score, the sicker the patient, with a higher risk of death) was used to assess the severity of the condition and outcome. ICU outcome was defined as 1) moved from the ICU to a ward/recovering or 2) no response to ICU treatment/deceased. All data were transferred to statistical software for analysis. Logistic regression analysis was used to examine the outcome related to PU/I development, SOFA, and mJ/C scores. Descriptive contingency tables of different scenarios were used to further evaluate relationships among different risk factors related to mortality; the Wald χ2 test was used to assess the statistical significance of the contingency tables.

RESULTS

Of the 6582 patients admitted, 6089 were included for analysis. Two hundred, one (201) had a PU/In on admission, 212 had missing mJ/C or SOFA scores, and ICU outcome was undetermined in 80 patients. Patient mean age was 61.1 ± 15.8 (range 18-94) years; 3891 (63.9%) were male, average length of stay (LOS) was 3.6 days, denoted by quartile (Q) (median 1.58 days; Q1: 0.9, Q3: 3.9 days), and 1589 (26.1%) stayed 3 days or more in the ICU. The incidence of PU/I was 6.9% (423 patients), and ICU mortality rate was 9.1% (n=553). The mean LOS of patients with PU/I was 13.35 ± 15.56 days (median 8.95, Q1: 4.88, Q3: 16.2) and 2.84 ± 3.87 days for patients with no PU/I (median: 1.20, Q1: 0.90, Q3: 3.17; P <.0001). Mean LOS was 3.42 ± 5.95 days (median: 1.30, Q1: 0.90, Q3: 3.70) among recovering and 5.00 ± 7.17 days among deceased patients (median 2.56, Q1: 1.26, Q3: 6.40; P <.0001). The proportion of patients with an admission mJ/C score of 29 or less ranged from 48.8% to 51.5%, and the mean SOFA score was 7.0 ± 3.2. PU/I development and SOFA or mJ/C scores were independent predictors of mortality. The probability of a negative outcome was higher in persons with PU/Is compared to persons with no PU/Is. Persons with lower SOFA scores (ie, less severely ill patients) and higher mJ/C scores for each factor separately (ie, at low risk of PU/I development) each factor separately had a lower mortality risk.

CONCLUSION

PU/I development in critically ill patients treated at an ICU is an independent predictor of mortality, even though the PU/I incidence and hospital mortality were relatively low. The ICU admission SOFA and mJ/C score also were independent prognosticators of ICU mortality. Future research could focus on the role of different steps in the cascade of PU/I development, especially to the role of inflammation.