Biomaterial Database

Cardiovascular responses to noxious stimuli during isoflurane anesthesia are minimally affected by anesthetic action in the brain. 1995

J F Antognini, and K Berg

University of California-Davis, Department of Anesthesiology 95616-8634, USA.

We investigated the ability of isoflurane to ablate cardiovascular responses to a noxious stimulus (dew-claw clamp) in 10 goats during isoflurane delivery throughout the body and with selective delivery to either the head or torso. Whole-body minimum alveolar anesthetic concentration (MAC) and the concentration blocking autonomic responses (MAC-BAR) were determined. Next, cranial blood (jugular vein) was drained into an oxygenator and reinfused into the head (carotid artery). In six animals (Group I) isoflurane to the torso was maintained at 0.2%-0.3%, and the cranial isoflurane concentration adjusted to determined MAC-BAR; in three animals (Group II) cranial isoflurane was maintained at 0.2%-0.3%, and the end-tidal isoflurane adjusted to determine MAC-BAR. Whole-body MAC was 1.4% +/- 0.3%; whole-body MAC-BAR was 3.7% +/- 0.4%, a concentration range associated with hypotension (46 +/- 8 mm Hg). During bypass, MAC-BAR was 5.6% +/- 2.4% for Group I (P < 0.05) and 2.2% +/- 0.7% for Group II (P < 0.05). Changes in blood pressure, but not heart rate, correlated with the isoflurane concentration, both during the whole-body period and bypass period for Groups I and II. We conclude that isoflurane suppresses the arterial blood pressure response to noxious stimuli, but only with concomitant hypotension, and that the brain has little influence on this response, as its MAC-BAR substantially exceeded whole-body MAC-BAR.

UI	MeSH Term	Description	Entries
D007530	Isoflurane	A stable, non-explosive inhalation anesthetic, relatively free from significant side effects.
D010146	Pain	An unpleasant sensation induced by noxious stimuli which are detected by NERVE ENDINGS of NOCICEPTIVE NEURONS.	Suffering, Physical,Ache,Pain, Burning,Pain, Crushing,Pain, Migratory,Pain, Radiating,Pain, Splitting,Aches,Burning Pain,Burning Pains,Crushing Pain,Crushing Pains,Migratory Pain,Migratory Pains,Pains, Burning,Pains, Crushing,Pains, Migratory,Pains, Radiating,Pains, Splitting,Physical Suffering,Physical Sufferings,Radiating Pain,Radiating Pains,Splitting Pain,Splitting Pains,Sufferings, Physical
D001794	Blood Pressure	PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.	Systolic Pressure,Diastolic Pressure,Pulse Pressure,Pressure, Blood,Pressure, Diastolic,Pressure, Pulse,Pressure, Systolic,Pressures, Systolic
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D006041	Goats	Any of numerous agile, hollow-horned RUMINANTS of the genus Capra, in the family Bovidae, closely related to the SHEEP.	Capra,Capras,Goat
D006339	Heart Rate	The number of times the HEART VENTRICLES contract per unit of time, usually per minute.	Cardiac Rate,Chronotropism, Cardiac,Heart Rate Control,Heartbeat,Pulse Rate,Cardiac Chronotropy,Cardiac Chronotropism,Cardiac Rates,Chronotropy, Cardiac,Control, Heart Rate,Heart Rates,Heartbeats,Pulse Rates,Rate Control, Heart,Rate, Cardiac,Rate, Heart,Rate, Pulse
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D018685	Anesthetics, Inhalation	Gases or volatile liquids that vary in the rate at which they induce anesthesia; potency; the degree of circulation, respiratory, or neuromuscular depression they produce; and analgesic effects. Inhalation anesthetics have advantages over intravenous agents in that the depth of anesthesia can be changed rapidly by altering the inhaled concentration. Because of their rapid elimination, any postoperative respiratory depression is of relatively short duration. (From AMA Drug Evaluations Annual, 1994, p173)	Inhalation Anesthetic,Inhalation Anesthetics,Anesthetic Gases,Anesthetic, Inhalation,Gases, Anesthetic