Pre-injury beta blocker use does not affect the hyperdynamic response in older trauma patients

Purpose: Trauma dogma dictates that the physiologic response to injury is blunted by beta-blockers and other cardiac medications. We sought to determine how the pre-injury cardiac medication profile influences admission physiology and post-injury outcomes. Materials and Methods: Trauma patients older than 45 evaluated at our center were retrospectively studied. Pre-injury medication profiles were evaluated for angiotensin-converting enzyme inhibitors / angiotensin receptor blockers (ACE-I/ARB), beta-blockers, calcium channel blockers, amiodarone, or a combination of the above mentioned agents. Multivariable logistic regression or linear regression analyses were used to identify relationships between pre-injury medications, vital signs on presentation, post-injury complications, length of hospital stay, and mortality. Results: Records of 645 patients were reviewed (mean age 62.9 years, Injury Severity Score >10, 23%). Our analysis demonstrated no effect on systolic and diastolic blood pressures from beta-blocker, ACE-I/ARB, calcium channel blocker, and amiodarone use. The triple therapy (combined beta-blocker, calcium channel blocker, and ACE-I/ARB) patient group had significantly lower heart rate than the no cardiac medication group. No other groups were statistically different for heart rate, systolic, and diastolic blood pressure. Conclusions: Pre-injury use of cardiac medication lowered heart rate in the triple-agent group (beta-blocker, calcium channel blocker, and ACEi/ARB) when compared the no cardiac medication group. While most combinations of cardiac medications do not blunt the hyperdynamic response in trauma cases, patients on combined beta-blocker, calcium channel blocker, and ACE-I/ARB therapy had higher mortality and more in-hospital complications despite only mild attenuation of the hyperdynamic response.