Can an alternative umbilical arterial catheter solution and flush regimen decrease iatrogenic hemolysis while enhancing nutrition? A double-blind, randomized, clinical trial comparing an isotonic amino acid with a hypotonic salt infusion.
OBJECTIVE
In the process of sampling blood through an umbilical arterial catheter (UAC), infant blood comes into stagnant contact with infusion solution in the "waste syringe" before being reinfused. We have previously demonstrated in vitro that this process is associated with less hemolysis of red blood cells (RBCs) with use of an isotonic solution compared with a hypotonic 0.25 normal saline (NS) solution. The objective of this study was to compare the in vivo effect on hemolysis of 2 UAC infusion/flush regimens (an isotonic regimen vs a hypotonic regimen) and to assess the early nutritional benefit of an amino acid solution as the isotonic UAC infusion solution.


METHODS
Infants who had a birth weight of < or =1.5 kg and were expected to have a UAC for > or =3 days were enrolled within 24 hours of life into this prospective, double-blind, randomized, clinical trial of 2 UAC infusion solution/flush regimens. Power analysis demonstrated that 40 infants were needed to determine differences in hemolysis quantified by plasma-free hemoglobin (PFH) level. Nutrition from glucose was evaluated by measurement of daily dextrose calories. C-peptide was measured to evaluate endogenous insulin production. Adverse events and protein tolerance were tracked.


RESULTS
Twenty-two infants (mean gestational age: 27 weeks; 945 g birth weight) were enrolled in each group, for an average of 4.2 days (range: 2.5-8 days). There were no group differences in demographics. PFH levels were lower for infants who received isotonic amino acid (IAA) in comparison with 0.25 NS (33 +/- 14 mg/dL vs 62 +/- 27 mg/dL, respectively). C-peptide was higher in those who received IAA, as were nonprotein calories received on days 4 to 6 of the study (51 +/- 11 kcal/kg/day vs 44 +/- 12 kcal/kg/day, IAA vs 0.25 NS, respectively).


CONCLUSIONS
Lower PFH levels in IAA versus 0.25 NS group were consistent with our hypothesis of decreased hemolysis with an isotonic infusion/flush regimen. IAA use may also allow greater early glucose nutrition, as indicated by the higher level of endogenous insulin production and improved glucose tolerance. IAA seems to be a superior UAC solution to 0.25 NS in that it is associated with less hemolysis and improved nutrition.
Department of Pediatrics, Section of Neonatal-Perinatal Medicine, Children's Mercy Hospitals and Clinics, University of Missouri-Kansas City School of Medicine, Kansas City, Missouri 64108, USA. jjackson@cmh.edu
Jodi K
JK
Jackson
Deborah J
DJ
Biondo
Janice M
JM
Jones
Pamala J
PJ
Moor
Stephen D
SD
Simon
Robert T
RT
Hall
Howard W
HW
Kilbride
D000596:Amino Acids / Q000008:administration & dosage; D002406:Catheterization, Peripheral / Q000295:instrumentation / Q000379:methods*; D004311:Double-Blind Method; D004573:Electrolytes; D005947:Glucose / Q000378:metabolism; D006454:Hemoglobins / Q000032:analysis; D006461:Hemolysis / Q000187:drug effects*; D006801:Humans; D007038:Hypotonic Solutions / Q000009:adverse effects / Q000494:pharmacology*; D007049:Iatrogenic Disease / Q000517:prevention & control*; D007231:Infant, Newborn / Q000097:blood* / Q000378:metabolism; D007552:Isotonic Solutions / Q000009:adverse effects / Q000494:pharmacology*; D057947:Parenteral Nutrition Solutions; D010289:Parenteral Nutrition, Total; D011446:Prospective Studies; D012996:Solutions; D014469:Umbilical Arteries
D000596:Amino Acids; D004573:Electrolytes; D006454:Hemoglobins; D007038:Hypotonic Solutions; D007552:Isotonic Solutions; D057947:Parenteral Nutrition Solutions; D012996:Solutions; C545824:amino-acid, glucose, and electrolyte solution; D005947:Glucose