The effect of Operation Iraqi Freedom on trauma care at a military treatment facility.

INTRODUCTION: The deployment of several medical units at the beginning of Operation Iraqi Freedom (OIF) significantly affected the staffing at William Beaumont Army Medical Center (WBAMC). We theorized that the resultant shortage of medical personnel adversely affected the outcome of trauma patients treated at our facility. MATERIALS AND METHODS: We performed a retrospective review of 2 groups of trauma patients, treated from 2000 to 2002 and from 2003 to 2005, that represented trauma patients cared for before and after OIF began. RESULTS: The volume of patients decreased from 2000-2002 to 2003-2005; however, the mortality rate (4.81 vs. 5.14, p = 0.740), injury severity score, hospital stay, intensive care unit stay, and ventilator time were unchanged. This is despite the trauma diversion time increased from 32.8 minutes per day to 289.2 minutes per day. CONCLUSION: Since the beginning of OIF, WBAMC has been limiting in its volume of trauma patients, but this has not affected the outcomes.

Ventilation-perfusion relationships following experimental pulmonary contusion.

Ventilation-perfusion changes after right-sided pulmonary contusion (PC) in swine were investigated by means of the multiple inert gas elimination technique (MIGET). Anesthetized swine (injury, n = 8; control, n = 6) sustained a right-chest PC by a captive-bolt apparatus. This was followed by a 12-ml/kg hemorrhage, resuscitation, and reinfusion of shed blood. MIGET and thoracic computed tomography (CT) were performed before and 6 h after injury. Three-dimensional CT scan reconstruction enabled determination of the combined fractional volume of poorly aerated and non-aerated lung tissue (VOL), and the mean gray-scale density (MGSD). Six hours after PC in injured animals, Pa(O(2)) decreased from 234.9 +/- 5.1 to 113.9 +/- 13.0 mmHg. Shunt (Q(S)) increased (2.7 +/- 0.4 to 12.3 +/- 2.2%) at the expense of blood flow to normal ventilation/perfusion compartments (97.1 +/- 0.4 to 87.4 +/- 2.2%). Dead space ventilation (V(D)/V(T)) increased (58.7 +/- 1.7% to 67.2 +/- 1.2%). MGSD increased (-696.7 +/- 6.1 to -565.0 +/- 24.3 Hounsfield units), as did VOL (4.3 +/- 0.5 to 33.5 +/- 3.2%). Multivariate linear regression of MGSD, VOL, V(D)/V(T), and Q(S) vs. Pa(O(2)) retained VOL and Q(S) (r(2) = .835) as independent covariates of Pa(O(2)). An increase in Q(S) characterizes lung failure 6 h after pulmonary contusion; Q(S) and VOL correlate independently with Pa(O(2)).