Use of the SOFA score in an Indian cancer hospital ICU

Objective

To determine the pattern of organ failure in critically ill cancer patients and whether the SOFA score is useful in predicting outcome.

Methods

Six hundred and two consecutive admissions (369 males, 233 females) from July 2004 to September 2005 were prospectively studied in a 21-bed ICU-HDU. Two hundred and sixty-three patients were admitted following surgery (Group 1), 209 patients with solid tumours were admitted from the wards (Group 2) and 130 had haematological malignancies, lymphoma or myeloma (Group 3). Mean SAPS II was 36.0 ± 9.4. Length of ICU stay was 5.2 ± 6.6 days. Parameters for calculating the SOFA score were assessed daily until ICU discharge. The total SOFA score on day 1 (SOFA1), the highest SOFA score of the first 3 days (MAX3) and during the ICU stay (MAXSOFA), the change in SOFA score between day 2 and day 1 (DELTA1) and the MEANSOFA (total SOFA score for all days/days in ICU) were calculated. Organ failure was present if the score for any organ was >2 in the first 48 hours.

Results

ICU mortality was 33.6% (11%, 36% and 75% for Groups 1, 2 and 3, respectively, P < 0.000). Nonsurvivors had higher organ scores and SOFA score on day 1 (6.3 ± 4.1 vs 1.7 ± 2.1, P < 0.001) and until day 7. Respiratory (RS) failure was the most common (17.1%), followed by coagulation (11.8%), central nervous system (CNS) failure (8.8%), cardiovascular (CVS) failure (7.8%), renal and liver failure (3.5% and 2.5%; P < 0.000). The incidence of RS, coagulation, CVS and CNS failure on day 1 was very high in Group 3 (40%, 38%, 19% and 16.2%, respectively) and least in Group 1 (5.3%, 1.1%, 1.9% and 3.4%, P < 0.000). Patients in Group 3 had significantly higher SOFA1 (6.6 ± 4.0 vs 3.5 ± 3.4 for Group 2 and 1.4 ± 2.0 for Group 1, P < 0.000), and scores for all organ systems on day 1. Of the organ failures developing within 48 hours, CVS failure was associated with the highest mortality (86.3%), while RS failure and coagulation failure were associated with mortality of 68.9% and 75.6%, respectively. Group 1 patients had significantly less mortality with RS (30%), CNS (30%) and coagulation (50%) failure compared with the other groups. A total 13.6% of patients with no organ failures within 48 hours died, while patients with one, two, three and >3 organ failures had a mortality of 51.3%, 73.3%, and 92% and 100%, respectively. For patients staying >1 day, the area under the ROC (SE) for SOFA1, DELTA1, MEANSOFA, MAXSOFA and MAX3 were 0.81 (0.02), 0.65 (0.03), 0.91 (0.02), 0.91 (0.02) and 0.87 (0.02), respectively. The univariate ORs (95% CI) were highest (1.9 [1.7–2.1] and 1.6 [1.5–1.7]) for MEANSOFA and MAX3, respectively, and lowest (1.4 [1.2–1.6]) for DELTA1.

Conclusion

Patients with haematological malignancies have a higher incidence of coagulation failure and worse outcome with multiple organ failure compared with general ICU patients. The MEANSOFA best discriminates between survivors and nonsurvivors, while SOFA1 and MAX3 were superior to DELTA1.