Comparison of dobutamine and enoximone for low output states following cardiac surgery.

Low output syndrome sometimes complicates early postoperative states following cardiac surgery. A comparative study of haemodynamic responses to enoximone and dobutamine was carried out in two groups of 20 patients each, during a 24-hour postoperative observation period. Parameters in addition to routine measurements were determined using a pulmonary artery catheter. Enoximone, 1 mg/kg i.v. in total, was given in the first 20 minutes. The infusion was then reduced to 3-20 micrograms/kg/minute for the next 24 hours. Dobutamine was administered in a continuous dose of 5-7 micrograms/kg/minute over the same period. After 15 minutes' therapy with enoximone, cardiac index increased from 2.31 +/- 0.34 litres/minute/m2 to 3.30 +/- 0.38 litres/minute/m2; after 120 minutes to 3.83 +/- 0.60 litres/minute/m2 and after 24 hours to 4.34 +/- 0.50 litres/minute/m2. Pulmonary capillary wedge pressure at the same intervals decreased from 15.21 +/- 1.65 mm Hg initially to 12.11 +/- 2.83, 11.2 +/- 4.50 and 8.77 +/- 2.98 mm Hg. After dobutamine, cardiac index rose from 2.33 +/- 0.60 litres/minute/m2 to 2.90 +/- 0.81 (15 minutes), 3.52 +/- 0.74 (120 minutes) and 4.12 +/- 1.07 litres/minute/m2 (24 hours). The pulmonary wedge pressure values decreased in this group, from 15.20 +/- 3.14 mm Hg at the beginning to 13.74 +/- 3.02 (15 minutes), 12.17 +/- 5.25 (120 minutes) and 9.81 +/- 4.23 mm Hg (24 hours). The enoximone group showed a diminution of systolic arterial pressure of 14% in the first 120 minutes, with a return to initial values after 24 hours.(ABSTRACT TRUNCATED AT 250 WORDS)