[Value of the Hannover Intensive Score (HIS) in internal medicine intensive care]

Scoring systems are important tools for quality control and stratification of study populations in intensive care medicine. The study aims to systematically evaluate predictive ability and severity classification ability of the combined physiologic-therapeutic Hannover Intensiv Score (HIS). Such data are not existing regarding medical intensive care medicine.

1060 consecutive patients (ICU stay > 4 hours) being admitted to a medical ICU were prospectively investigated. HIS was determined for all patients each day during ICU stay. The results were compared to the physiologically based APACHE II and to the therapeutically based TISS, which both were determined as well.

HIS provided sufficient discrimination between survival and nonsurvival [hospital mortality; area under the ROC curve (AUC) = 0.822] with no significant differences compared to APACHE II (AUC = 0.838) and TISS (AUC = 0.798), respectively. During longer course of ICU stay HIS offers better outcome prognostication compared to the unilateral systems with respect to specificity and total correct classification rate. There was a nearly linear increase of hospital mortality with an increase of day-1-HIS. The same was observed with APACHE II and TISS. Mean day-1-scores for survivors were significantly higher compared to non-survivors with all systems (p < 0.0001). Day-1-HIS moderately correlates with both other systems (APACE II: r = 0.766; TISS: r = 0.814).

The Hannover Intensiv Score as a model of a combined physiologic-therapeutic scoring system was successfully validated concerning hospital outcome prediction and severity of disease classification in a large medical ICU population. Thus, for these applications it can be used in similar German ICUs. A main argument for applying the system is the employment of a fairly small set of easily accessible parameters.