There is increasing interest in intra-abdominal pressure (IAP) and intra-abdominal hypertension (IAH) in critically ill patients. This study investigated the effects and outcomes of elevated IAP in a trauma intensive care unit (ICU) population.

Eleven consecutive critically ill patients admitted to the trauma ICU at Pusan National University Hospital Regional Trauma Center were included in this study. IAP was measured every 8?12 hours (intermittently) for 72 hours. IAP was registered as mean and maximal values per day throughout the study period. IAH was defined as IAP ≥12 mmHg. Abdominal compartment syndrome was defined as IAP ≥20 mmHg plus ≥1 new organ failure. The main outcome measure was in-hospital mortality.

According to maximal and mean IAP values, 10 (90.9%) of the patients developed IAH during the study period. The Sequential Organ Failure Assessment (SOFA) score was significantly higher in patients with IAP ≥20 mmHg than in those with IAP <20 mmHg (16 vs. 5, p=0.049). The hospital mortality rate was 27.3%. Patients with a maximum IAP ≥20 mmHg exhibited significantly higher hospital mortality rates (p=0.006). Non-survivors had higher maximum and mean IAP values.

Our results suggest that an elevated IAP may be associated with a poor prognosis in critically ill trauma patients.

Preventable Trauma Death Rate (PTDR) using Trauma and Injury Severity Score (TRISS) has been most widely used as a quality indicator in South Korea. However, this method has a small number of deaths corresponding to the denominator. Therefore, it is difficult to check the change of quality improvement for annual mortality, and there is a disadvantage that variation is severe. Therefore, we attempted to improve the quality of the mortality evaluation by reducing the variation by applying the PARK Index (preventable major trauma death rate, PMTDR) which can increase the number of denominator significantly. And the Save score (S-score) was also examined as another quality indicator.

In the PARK Index, the denominator is number of all patients who have survival probability (Ps) larger than 0.25. Numerator is the number of deaths among these. The PARK Index includes only patients with ISS >15. The S-score is calculated in the same way as the W-score, but the S-score includes only patients with ISS >15, which is a difference from the W-score.

PARK Index decreased annually and was 12.9 (37/287) in 2014, 9.6 (33/343) in 2015, and 7.3 (52/709) in 2016. S-score increased annually and was ?0.29 in 2014, 4.21 in 2015, and 8.75 in 2016.

PARK Index and S-score improved annually. This shows that both quality indicators are improving year by year. PARK Index (PMTDR) has 9.5-fold increase in denominator overall compared to PTDR by TRISS. The S-score used only ISS >15 patients as a denominator. Therefore, there is an advantage that the numerical value change is larger than the W-score. In addition, S-score is not affected by the ratio of major trauma patients to minor trauma patients.