ENHANCED VENTRICULAR RECOVERY FROM HIGH-DOSE GLUCOSE, INSULIN AND POTASSIUM WITH CARDIOPULMONARY BYPASS SUPPORT PRIOR TO CARDIOPLEGIC ARREST

The concept that a beneficial preconditioning effect in ventricular re covery exists using high dose glucose (0.5 mg/kg), insulin (0.3 unit/k g), and potassium (0.2 mmol/kg) (GIK) with 20 min of normothermic card iopulmonary bypass support (CPB) prior to 60 min of cardioplegic arres t (CA) was tested using 32 mongrel dogs divided into four subset test groups. Group 1 was given GIK and 20 min of CPB prior to CA, Group 2 w as given GIK systemically over 10 min but no CPB prior to CA, Group 3 underwent 20 min of CPB without GIK and Group 4 was the control group with no GIK and no CPB assist. To focus specifically on in vivo ventri cular recovery, dP/dT (mmHg/sec), developed pressure (dP) (mmHg), and segmental shortening (SS) (%) were measured prior to CPB, then 15, 30, 60, and 90 min after weaning from CPB, while left atrial pressure was kept constant. The average dP/dT (% recovery) at 60 min in Group 1 wa s 1,454 (122 %) and significantly higher (P less-than-or-equal-to 0.05 ) than Groups 2: 1,189 (99 %), 3: 1,027 (79 %) and 4: 1,030 (82 %). De veloped pressure at 90 min (% recovery) in Group 1, 88 (111 %) was als o better than Groups 3, 74 (86 %), and 4, 72 (87 %) (P less-than-or-eq ual-to 0.05). Segmental shortening (% recovery) at 30 min was better i n Group 1 (94 %) than in Groups 2 (59 %), 3 (73 %) and 4 (68 %). We co nclude that GIK added to 20 min of CPB support prior to cardioplegic a rrest enhances post CPB ventricular recovery and weaning from CPB.