Narrow-pore flow behavior of blood cells in cardioplegic suspension.
Cardioplegia alters the ionic composition of the myocardium and also the blood in a way that may influence the cellular capillary flow behavior. We measured changes in RBC volume and narrow-pore flow resistance of blood cardioplegia versus crystalloid medium. Potassium, magnesium and sodium as osmotic control caused an expected cell shrinkage and reduced the flow resistance through 3 microm pores; however, stressing the osmosis further resulted in increased resistance. No major effects were seen with the 5 microm filters. Twenty percent blood cells in the cardioplegic medium caused a 360% increase in 5 microm pore resistance. There were no obvious additional filterability effects of the cardioplegic additives other than their osmotic patterns. There may be a theoretical advantage in having a cell-free medium in terms of flow resistance. Using blood cardioplegia, a limited hypertonicity may be beneficial in reducing the capillary flow resistance of RBC.
Lindmark
K
K
Department of Surgical and Perioperative Sciences, Section for Surgery and Cardiothoracic Surgery, Umeå University Hospital, Sweden. kristerlindmark@hotmail.com
Engström
K G
KG
D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity / Q000187:drug effects; D001810:Blood Volume / Q000187:drug effects; D002314:Cardioplegic Solutions / Q000008:administration & dosage*; D001026:Coronary Artery Bypass / Q000379:methods; D003327:Coronary Disease / Q000503:physiopathology* / Q000628:therapy*; D000077324:Crystalloid Solutions; D004907:Erythrocyte Deformability / Q000187:drug effects; D004912:Erythrocytes / Q000187:drug effects*; D005260:Female; D006324:Heart Arrest, Induced / Q000379:methods; D006801:Humans; D007432:Intraoperative Period; D007552:Isotonic Solutions; D016014:Linear Models; D008297:Male; D008851:Micropore Filters; D008875:Middle Aged; D010952:Plasma Substitutes / Q000008:administration & dosage; D011336:Probability; D012016:Reference Values; D015532:Rehydration Solutions / Q000008:administration & dosage; D012212:Rheology; D012680:Sensitivity and Specificity; D014655:Vascular Resistance / Q000187:drug effects
D002314:Cardioplegic Solutions; D000077324:Crystalloid Solutions; D007552:Isotonic Solutions; D010952:Plasma Substitutes; D015532:Rehydration Solutions