Am J Perinatol 1984; 1(3): 223-226
DOI: 10.1055/s-2007-1000009
ORIGINAL ARTICLE

© 1984 by Thieme Medical Publishers, Inc.

Effect of Cephalic Pressure on Fetal Cerebral Blood Flow

William F. O'Brien L. Cdr. , S. Edward Davis Capt. , Michael P. Grissom L. Cdr. , Robert R. Eng Capt. , Steven M. Golden Cdr. 
  • Departments of Obstetrics and Gynecology and Pediatrics, Uniformed Services University School of Medicine and Nuclear Sciences Division, Armed Forces Radiobiologic Research Institute, Bethesda, Maryland
Further Information

Publication History

Publication Date:
04 March 2008 (online)

ABSTRACT

During vaginal delivery, the fetus is exposed to a variety of stresses including pressure applied to the fetal skull. In order to study the effects of this stress on fetal homeo-stasis, we monitored the response to external cephalic compression applied to the acutely prepared near-term fetal lamb. In response to cephalic pressure, we noted initial bradycardia followed by sustained tachycardia. Mean arterial pressure and pulse pressure rose during cephalic pressure and gradually returned to baseline levels. Cerebral blood flow fell approximately 95% early in the period of compression. This fall in total cerebral blood flow was accompanied by a redistribution of cerebral flow. During this time, a smaller percentage of cerebral blood flow was found in the cortex and a greater percentage was directed to the brainstem.