Hemodiafiltration—A Technique for Physiological Correction of Priming Solution in Pediatric Cardiac Surgery: An In Vitro Study

Abstract

Pediatric cardiopulmonary bypass (CPB) circuit invariably requires priming with packed red blood cells (PRBCs). Metabolic composition of stored PRBCs is unphysiological and becomes worse with increasing duration of storage. It is recommended to correct these abnormalities before initiation of CPB. We tested the hypothesis that hemodiafiltration of the prime with 0.45% saline is sufficient for reducing the metabolic load and reaching a physiologic state. In an in vitro study, 100 mL of blood each from 45 units of PRBCs stored for 3–20 days were used for priming the 45 neonatal CPB circuits. Based upon the method used for removal of excess crystalloid from the prime, circuits were divided into three groups. Group 1: Direct removal through manifold line. Group 2: Ultrafiltration of prime. Group 3: Hemodiafiltration of the prime. Blood gas analyses were obtained from the PRBCs and from the prime before and after removal of crystalloid. Both direct removal of crystalloid and ultrafiltration resulted in significant reduction in biochemical and metabolic load of blood (P < 0.001). However, the final composition of the prime was far from being physiological. Hemodiafiltration resulted in improvement of metabolic parameters to near physiological range (lactate: 33.8 ± 4.44 vs. 14 ± 2.53 mg/dL, pH: 7.05 ± 0.15 vs. 7.34 ± 0.06, bicarbonates: 4.83 ± 0.59 vs. 27.6 ± 2.94 meq/L; P < 0.001). Similarly, sodium (147.76 ± 12.73 vs. 144.6 ± 5.96 meq/L) and potassium (9.6 ± 2.83 vs. 4.23 ± 0.37 meq/L) also changed significantly (P < 0.001) to near physiologic range. Hemodiafiltraion of final prime is a simple, efficients and rapid method of correcting the biochemical parameters and reducing the metabolic load of stored PRBCs towards the physiological range before initiating the CPB.

Zero‐balance ultrafiltration of the priming blood modifies the priming components and improves the clinical outcome in infants undergoing cardiopulmonary bypass: A randomized controlled trial

“…However, massive transfusions given quickly at the beginning of CPB may overwhelm the capacity of the liver. In addition, hypothermia and depressed hepatic functions may increase citrate toxicity . In our study, we demonstrated that the Z‐BUF of the priming blood diminished lactate as a weak acid in the priming blood: the level of lactate was significantly lower in the Z‐BUF group than in the control group at admission to the ICU.…”

“…Rapid and massive transfusions of the priming blood may lead to hyperkalemia, cardiac arrhythmias, and cardiac arrest and acute hypernatremia‐induced brain shrinkage may result in intracranial hemorrhage and venous thrombosis . We performed Z‐BUF on the priming blood by using 0.45% sodium chloride and observed improvement in the levels of potassium, sodium, and chlorine.…”

“…Hyperglycemia, in association with hyperlactatemia, may result in neurological disorders . It is, therefore, advisable to diminish the glucose and lactate level in the prime.…”

“…Priming the CPB circuit with packed red blood cells (PRBCs) triggers a rapid transfusion of a massive metabolic load. Enormous PRBC transfusions can result in complications because of hyperkalemia, hypernatremia, hyperglycemia, citrate toxicity, and acidosis and even lead to stroke, kidney failure, and cardiac arrest . A higher‐than‐normal plasma osmolarity may indicate hyperglycemia and hypernatremia, with sodium ions and glucose molecules constituting the major contributors to the osmolarity.…”

“…Enormous PRBC transfusions can result in complications because of hyperkalemia, hypernatremia, hyperglycemia, citrate toxicity, and acidosis and even lead to stroke, kidney failure, and car diac arrest. 4 A higher-than-normal plasma osmolarity may indicate hyperglycemia and hypernatremia, with sodium ions and glucose molecules constituting the major contributors to the osmolarity. The published values of sodium and glucose in PRBCs are 156 mEq/L and 270 mg/dL on average, respec tively, and massive transfusions in infants with hyperosmolar PRBCs may exert a detrimental influence on the central ner vous system, the renal system, and the general metabolic pro cess.…”