Early life events, sex, and arterial blood pressure in critically ill infants.
OBJECTIVE
To determine whether photo-protecting total parenteral nutrition in preterm infants influences arterial blood pressure differently according to gender. Blood pressure is influenced by complex mechanisms of vasomodulation. Oxidants are mediators and effectors in such reactions. Shielding total parenteral nutrition from light contributes to decrease the generation of peroxides. Girls may be better protected against an oxidant load than boys. We questioned whether shielding total parenteral nutrition may have cardiovascular effects that are influenced by gender.


METHODS
A post hoc subgroup analysis of the effect of shielding parenteral nutrition from light.


METHODS
Neonatal intensive care unit.


METHODS
Preterm infants <1000 g with indwelling arterial catheters who received light exposed (n = 20) or light protected (n = 20) parenteral nutrition.


METHODS
Invasive monitoring, total parenteral nutrition.


RESULTS
Arterial blood pressure was recorded hourly and compared between light exposed and light protected over the first week of life; timed average maximum velocity (m/s) was measured in the superior mesenteric artery by Doppler; presence of ductus arteriosus was documented by cardiac ultrasound. Data were analyzed by analysis of variance. No differences were noted between light exposed and light protected in clinical determinants that may influence blood pressure. There was an interaction (p < .01) between gender and total parenteral nutrition on blood pressure. In girls (n = 17), systolic and diastolic blood pressures were higher (p < .01) and heart rate lower (p < .01) during light exposed. There was no effect on BP observed in boys (n = 23). The linear correlation between timed average maximum velocity and systolic blood pressure was positive (p < .05). There was no echocardographic difference in hemodynamic variables between boys (n = 21) and girls (n = 9) who had a patent ductus.


CONCLUSIONS
Failure to shield total parenteral nutrition from light results in higher blood pressure in a selected population of critically ill female infants. This information adds to our understanding of the multiple determinants involved in optimizing arterial blood pressure in a critical care environment.
Chessex
Philippe
P
Division of Neonatology, Departments of Pediatrics, Children's and Women's Health Centre of BC and University of British Columbia, Vancouver, BC, Canada. pchessex@cw.bc.ca
Khashu
Minesh
M
Harrison
Adele
A
Hosking
Martin
M
Sargent
Michael
M
Lavoie
Jean-Claude
JC
D001794:Blood Pressure; D016638:Critical Illness; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D008297:Male; D010288:Parenteral Nutrition / Q000379:methods*; D010545:Peroxides; D047928:Premature Birth; D012737:Sex Factors
D010545:Peroxides