Reducing intraoperative myocardial acidosis by continuous cardioplegic perfusion via the coronary sinus.
Continuous retrograde coronary sinus perfusion (RCSP) can deliver cardioplegic solution homogeneously to the myocardium via the disease-free venous system. However, administration of cardioplegic solution through the coronary venous system necessitates low pressure infusion which may limit the rate of cardioplegic delivery. In addition, infusion of the solution at low flow rates may not prevent the development of myocardial acidosis during arrest. To determine if RCSP is capable of limiting intraoperative myocardial acidosis, open-chest pigs, monitored by intramyocardial pH probes, underwent cardioplegic arrest with a single dose aortic root infusion followed by a 45-min period of no RCSP (Group 1), RCSP of 25 mEq/liter bicarbonate-buffered cardioplegic solution (Group 2), RCSP of blood-buffered cardioplegic solution (Group 3), and RCSP of histidine-buffered cardioplegic solution (Group 4). There were no significant differences between the groups with respect to baseline pH, with a range of 7.27 to 7.32. At the end of the 45-min arrest period, Group 2 had a statistically higher pH, 7.06 +/- 0.08, compared to Group 1, 6.74 +/- 0.08 (P less than 0.05). Hearts in Groups 3 and 4 demonstrated preservation of preischemic pH levels after 45 min of arrest, 7.29 +/- 0.07 and 7.37 +/- 0.10, respectively, significantly higher than either Group 1 or 2 (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
Johnson
D L
DL
Division of Cardiac Surgery, Johns Hopkins Medical Institutions, Baltimore, Maryland 21205.
Lahorra
J A
JA
Gott
V L
VL
Gardner
T J
TJ
D000138:Acidosis / Q000517:prevention & control*; D000818:Animals; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D009202:Cardiomyopathies / Q000517:prevention & control*; D002314:Cardioplegic Solutions / Q000008:administration & dosage* / Q000627:therapeutic use; D003326:Coronary Circulation; D006324:Heart Arrest, Induced; D006863:Hydrogen-Ion Concentration; D007431:Intraoperative Complications; D009206:Myocardium / Q000378:metabolism; D010477:Perfusion / Q000379:methods
D002314:Cardioplegic Solutions