Effects of primary resuscitation from shock on distribution of myocardial blood flow

Hemorrhagic shock alters heterogeneity of regional myocardial perfusion (RM P) in the presence of critical coronary stenosis in pigs. Conventional resu scitation has failed to reverse these effects. We hypothesized that improve ment of the resuscitation regime would lead to restoration of RMP heterogen eity. Diaspirin-cross-linked hemoglobin (10 g/dl; DCLHb) and human serum al bumin (8.0 g/dl; HSA) were used. After baseline, a branch of the left coron ary artery was stenosed; thereafter, hemorrhagic shock was induced. Resusci tation was performed with either DCLHb or HSA. At baseline, the fractcal di mension (D) of subendocardial myocardium was 1.31 +/- 0.083 (HSA) and 1.35 +/- 0.106 (DCLHb) (mean +/- SD). Coronary stenosis increased subendocardial D slightly but consistently only in the DCLHb group (1.39 +/- 0.104; P < 0 .05). Shock reduced subendocardial D: 1.21 +/- 0.093 (HSA; P = 0.10), 1.25 +/- 0.092 (DCLHb; P < 0.05). Administration of DCLHb increased subendocardi al D in 7 of 10 animals (1.31 +/- 0.097; P = 0.066). HSA was ineffective in this respect. DCLHb infusion restored arterial pressure and increased card iac index (CI) to 80% of baseline values. Administration of HSA left animal s hypotensive (69 mmHg) and increased CI to 122% of the average baseline va lue. Shock-induced disturbances of the distribution of RMP were improved by administration of DCLHb but not by HSA.