Biomaterial Database

Alteration of ovine fetal respiratory-like activity by diazepam, caffeine, and doxapram. 1977

W N Piercy, and M A Day, and A H Neims, and R L Williams

The effects of diazepam, caffeine citrate, and doxapram on fetal respiratory-like activity (RLA) were studied in 10 chronic sheep preparations (90 to 130 days' gestation). We define fetal RLA as regular changes in fetal tracheal pressure occurring with a frequency of at least 1 Hz and an amplitude greater than -5 mm. Hg in the absence of fluctuations in amniotic cavity pressure. In all maternal (8) and fetal (7) intravenous infusions of diazepam (5 to 10 mg.), RLA ceased almost instantaneously. The duration of fetal apnea varied from 29 to 70 minutes with a mean of 57 minutes, and on occasion, a gasping pattern preceded recovery of RLA. Maternal and fetal plasma concentrations of diazepam indicated rapid bidirectional placental transfer. Intravenous infusion of doxapram (3 mg.) to the fetus immediately initiated a transient episode of RLA in 19 of 20 trials. Fetal infusion of caffeine citrate (10 to 20 mg.), especially via the carotid artery, was also associated with the rapid onset of a transient episode of fetal breathing. Saline control infusions were without effect. Fetal blood gases and pH were not altered by the administration of diazepam, caffeine citrate, or doxapram. It is suggested that each drug owes its action on RLA to an effect on fetal central nervous system. The influence of pharmacologic agents on the process and interpretation of fetal monitoring requires continued attention.

UI	MeSH Term	Description	Entries
D007263	Infusions, Parenteral	The administration of liquid medication, nutrient, or other fluid through some other route than the alimentary canal, usually over minutes or hours, either by gravity flow or often by infusion pumping.	Intra-Abdominal Infusions,Intraperitoneal Infusions,Parenteral Infusions,Peritoneal Infusions,Infusion, Intra-Abdominal,Infusion, Intraperitoneal,Infusion, Parenteral,Infusion, Peritoneal,Infusions, Intra-Abdominal,Infusions, Intraperitoneal,Infusions, Peritoneal,Intra Abdominal Infusions,Intra-Abdominal Infusion,Intraperitoneal Infusion,Parenteral Infusion,Peritoneal Infusion
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011312	Pressure	A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Pressures
D012119	Respiration	The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (	Breathing
D001784	Blood Gas Analysis	Measurement of oxygen and carbon dioxide in the blood.	Analysis, Blood Gas,Analyses, Blood Gas,Blood Gas Analyses,Gas Analyses, Blood,Gas Analysis, Blood
D002110	Caffeine	A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes SMOOTH MUSCLE, stimulates CARDIAC MUSCLE, stimulates DIURESIS, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide PHOSPHODIESTERASES, antagonism of ADENOSINE RECEPTORS, and modulation of intracellular calcium handling.	1,3,7-Trimethylxanthine,Caffedrine,Coffeinum N,Coffeinum Purrum,Dexitac,Durvitan,No Doz,Percoffedrinol N,Percutaféine,Quick-Pep,Vivarin,Quick Pep,QuickPep
D003864	Depression, Chemical	The decrease in a measurable parameter of a PHYSIOLOGICAL PROCESS, including cellular, microbial, and plant; immunological, cardiovascular, respiratory, reproductive, urinary, digestive, neural, musculoskeletal, ocular, and skin physiological processes; or METABOLIC PROCESS, including enzymatic and other pharmacological processes, by a drug or other chemical.	Chemical Depression,Chemical Depressions,Depressions, Chemical
D003975	Diazepam	A benzodiazepine with anticonvulsant, anxiolytic, sedative, muscle relaxant, and amnesic properties and a long duration of action. Its actions are mediated by enhancement of GAMMA-AMINOBUTYRIC ACID activity.	7-Chloro-1,3-dihydro-1-methyl-5-phenyl-2H-1,4-benzodiazepin-2-one,Apaurin,Diazemuls,Faustan,Relanium,Seduxen,Sibazon,Stesolid,Valium
D004315	Doxapram	A central respiratory stimulant with a brief duration of action. (From Martindale, The Extra Pharmocopoeia, 30th ed, p1225)	Docatone,Dopram,Doxapram Hydrochloride,Hydrochloride, Doxapram
D005260	Female		Females