The diagnosis of cardiac dysfunction in critically III trauma patients with blunt chest trauma and presumed myocardial contusion: the critical nature of end diastolic volume

BACKGROUND: To evaluate prospectively the effectiveness of monitoring end-diastolic volume (EDV) vs pulmonary artery occlusion pressure (PAO) as an estimate of cardiac preload in hemodynamically unstable critically ill 23 myocardial contusion patients with blunt chest trauma admitted to a university trauma center.. METHODS: Patients were resuscitated (ATLS guidelines) with intubation and volume replacement for altered consciousness, hypoxemia or hemodynamic instability. Volume resuscitation and pulmonary artery catheterization were started to measure PAO, EDV, and oxygen utilization parameters. Myocardial performance was determined in both static (0., 24., 48., 72. hours) and dynamic condition after 500cc fluid bolus. RESULTS: A moderate injury severity (GCS 9, TS 11, ISS 34) with MVA mechanism (91%), an average ICU stay of 14 days and a 39% mortality were revealed. Correlation of PAO, EDV with CO, CI demonstrated that EDV is more reliable than PAO However, factoring heart rate into CO determination was more reliable than single preload estimates of EDV-PAO-HR, HR-EDV, and HR-PAO. EDV-PAO-HR were correlated more strongly with cardiac output from 24 to 96 hours. A higher AV02 decrease was associated with improved survival, and a nearly significant decrease in EDV. Dynamic comparison found no change in cardiac performance with a small volume challenge. CONCLUSION: Simultaneous consideration of PAO, EDV, HR allowed the most accurate determination of cardiac output.