These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: The effects of 21 or 30% O2 plus umbilical cord occlusion on fetal breathing and behavior.
    Author: Alvaro R, Weintraub Z, Alvarez J, Baier J, Cates D, Nowaczyk B, Martino C, Rigatto H.
    Journal: J Dev Physiol; 1992 Nov; 18(5):237-42. PubMed ID: 1307099.
    Abstract:
    We have shown previously that continuous fetal breathing can be induced by 100% O2 alone or combined with umbilical cord occlusion (Baier, Hasan, Cates, Hooper, Nowaczyk & Rigatto, 1990). To know whether it could also be induced by lower O2 concentrations plus cord occlusion, we studied 9 chronically instrumented fetal sheep (16 experiments) using our window model. After a baseline cycle [1 low voltage + 1 high voltage electrocortical activity (ECoG) epoch] the fetal lung was distended via an endotracheal tube to about 30 cm H2O. Inspired N2 (control) and 21 or 30% O2 were given for one cycle each. While on 21% or 30% O2 the umbilical cord was occluded (balloon cuff). In 10 out of 16 experiments breathing output (% maximum of integral of EMGdi x f) increased after cord occlusion from 80 +/- 48 (N2) to 2871 +/- 641 (SEM; P < 0.01); in 7 of them breathing became continuous. Arterial PO2 increased from 14 +/- 1 (N2) to 33.5 +/- 5 Torr (occlusion; P < 0.01). In the other 6 experiments breathing output decreased from 319 +/- 116 (N2) to 86 +/- 38 (occlusion; P < 0.01) and arterial PO2 changed from 18 +/- 1 (N2) to 22 +/- 5 Torr (occlusion; P = 0.4). Arterial PCO2 increased similarly after occlusion in both groups, those which did respond with increased breathing (to 46 +/- 2 Torr) and those which did not respond (to 48 +/- 3 Torr; P = 0.6). The percent low voltage ECoG and the behavioral score increased after occlusion in the responder group only.(ABSTRACT TRUNCATED AT 250 WORDS)
    [Abstract] [Full Text] [Related] [New Search]