Evaluation of I.V. labetalol for treatment of posttraumatic hyperdynamic state.

A hyperdynamic state, characterized by an elevated blood pressure and tachycardia is frequently seen during the first few days following severe multiple trauma. We examined the cardiovascular effects of the alpha and beta adrenoceptor blocking agent labetalol in patients presenting a hyperdynamic cardiovascular state some days after major trauma. Ten patients with a heart rate-systolic blood pressure product (RPP) of more than 2000 during 6 consecutive hours, despite normovolaemia, adequate ventilation, analgesia and sedation were investigated. After a mean dose of 2.1 +/- 1.2 mg X kg-1 (mean +/- SD) of labetalol injected intravenously over a 10-min period, heart rate decreased from 117 +/- 28 to 102 +/- 19 beats X min-1, systolic arterial pressure from 25 +/- 3.5 to 18.5 +/- 2.7 kPa, diastolic pressure from 11 +/- 1.7 to 9.5 +/- 1.7 kPa, mean arterial blood pressure from 15.5 +/- 2.1 to 12.4 +/- 2.1 kPa, and the RPP from 2880 +/- 867 to 1853 +/- 373. The beneficial effect of this dose lasted 24 h in 8 of 10 patients without additional administration. No important side effects such as cardiac arrhythmias, hypotension, or bronchospasm were noted. We conclude that labetalol used in fractional intravenous doses permits an adequate treatment of a "hypertension-tachycardia syndrome" in severely injured patients.