Myocardial and cerebral oxygen delivery are not adversely affected by cocaine administration to early-gestation fetal sheep.
OBJECTIVE
Cocaine administration to near-term pregnant sheep causes fetal hypoxemia, but oxygen delivery to the heart and brain are preserved because of increased blood flow. We hypothesized that cocaine administration during earlier fetal gestation impairs oxygen delivery to the heart and brain.


METHODS
Ten pregnant ewes and fetuses at 0.7 term gestation underwent surgical instrumentation. After 48 hours of recovery fetal blood pressure, heart rate, cerebral and myocardial blood flow, and arterial oxygen content were determined before and during cocaine administration to the ewe.


RESULTS
Fetal hypoxemia was not noted in these animals. Fetal myocardial blood flow increased from 220 +/- 100 ml per 100 gm per minute to 349 +/- 183 ml per 100 gm per minute (p=0.03), and oxygen delivery increased from 16 +/- 5 ml of oxygen per 100 gm per minute to 22 +/- ml of oxygen per 100 gm per minute (p=0.02). Fetal cerebral blood flow and oxygen delivery remained unchanged.


CONCLUSIONS
Cerebral and myocardial oxygen delivery are unimpeded by maternal cocaine administration in 0.7 term gestation ovine fetuses.
Peña
A E
AE
Department of Pediatrics, University of Florida College of Medicine, Gainesville, 32610, USA.
Burchfield
D J
DJ
Abrams
R M
RM
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D002560:Cerebrovascular Circulation / Q000187:drug effects; D003042:Cocaine / Q000008:administration & dosage / Q000009:adverse effects*; D005260:Female; D005318:Fetal Heart / Q000187:drug effects* / Q000378:metabolism; D005333:Fetus / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D006340:Heart Rate, Fetal / Q000187:drug effects; D007262:Infusions, Intravenous; D010100:Oxygen / Q000378:metabolism*; D011247:Pregnancy; D012756:Sheep
D003042:Cocaine; D010100:Oxygen