Traumatic coronary artery dissection: a case report and literature review.

BACKGROUND: Coronary artery dissection after blunt chest trauma is a rare, life-threatening condition. OBJECTIVES: To present a case of coronary artery dissection after blunt chest trauma and to outline the appropriate management of this condition based on a literature review. CASE REPORT: We report the case of a 50-year-old woman with traumatic coronary artery dissection after a high-speed motor vehicle collision. She presented to the Emergency Department via ambulance within a few hours of the collision, and her clinical condition deteriorated rapidly. A 12-lead electrocardiogram on arrival demonstrated anterolateral ST-segment elevation. The patient was intubated due to hypoxemic respiratory failure and she required inotropes for blood pressure support. Computed tomography imaging revealed pulmonary edema and right third and fourth rib fractures. Emergent angiography demonstrated dissection of her left main coronary artery, requiring placement of a stent. CONCLUSION: Early recognition of this clinical entity with a screening electrocardiogram, and aggressive management, may result in a favorable outcome. A literature review reveals that coronary artery bypass grafting, angiography with stent placement, and conservative management may all be considered viable treatment options for this condition.

Can peripheral venous blood gases replace arterial blood gases in emergency department patients?

OBJECTIVE: To determine if peripheral venous blood gas values for pH, partial pressure of carbon dioxide (Pco(2)) and the resultant calculated bicarbonate (HCO(3)) predict arterial values accurately enough to replace them in a clinical setting. METHODS: This prospective observational study was performed in a university tertiary care emergency department from June to December 1998. Patients requiring arterial blood gas analysis were enrolled and underwent simultaneous venous blood gas sampling. The following data were prospectively recorded: age, sex, presenting complaint, vital signs, oxygen saturation, sample times, number of attempts and indication for testing. Correlation coefficients and mean differences with 95% confidence intervals (CIs) were calculated for pH, Pco(2) and HCO(3). A survey of 45 academic emergency physicians was performed to determine the minimal clinically important difference for each variable. RESULTS: The 218 subjects ranged in age from 15 to 90 (mean 60.4) years. The 2 blood samples were drawn within 10 minutes of each other for 205 (96%) of the 214 patients for whom data on timing were available. Pearson's product-moment correlation coefficients between arterial and venous values were as follows: pH, 0.913; Pco(2), 0.921; and HCO(3), 0.953. The mean differences (and 95% CIs) between arterial and venous samples were as follows: pH, 0.036 (0.030-0.042); Pco(2), 6.0 (5.0-7.0) mm Hg; and HCO(3), 1.5 (1.3-1.7) mEq/L. The mean differences (+/- 2 standard deviations) were greater than the minimum clinically important differences identified in the survey. CONCLUSIONS: Arterial and venous blood gas samples were strongly correlated, and there were only small differences between them. A survey of emergency physicians suggested that the differences are too large to allow for interchangeability of results; however, venous values may be valid if used in conjunction with a correction factor or for trending purposes.