Journal of Cardiothoracic Surgery 2011, 6:110
Published: 16 September 2011
The original Logistic Organ Dysfunction Sore (LODS) excluded cardiac surgery
patients from its target population, and the suitability of this score in cardiac
surgery patients has never been tested. We evaluated the accuracy of the LODS and
the usefulness of its daily measurement in cardiac surgery patients. The LODS is not
a true logistic scoring system, since it does not use β-coefficients.
This prospective study included all consecutive adult patients who were admitted to
the intensive care unit (ICU) after cardiac surgery between January 2007 and December
2008. The LODS was calculated daily from the first until the seventh postoperative
day. Performance was assessed with Hosmer-Lemeshow (HL) goodness-of-fit test (calibration)
and receiver operating characteristic (ROC) curves (discrimination) from ICU admission
day until day 7. The outcome measure was ICU mortality.
A total of 2801 patients (29.6% female) with a mean age of 66.4 ± 10.7 years were
included. The ICU mortality rate was 5.2% (n = 147). The mean stay on the ICU was
4.3 ± 6.8 days. Calibration of the LODS was good with no significant difference between
expected and observed mortality rates on any day (p ≥ 0.05). The initial LODS had
an area under the ROC curve (AUC) of 0.81. The AUC was best on ICU day 3 with a value
of 0.93, and declined to 0.85 on ICU day 7.
Although the LODS has not previously been validated for cardiac surgery
patients it showed reasonable accuracy in prediction of ICU mortality in patients
after cardiac surgery.