Biomaterial Database

Propofol and hyperventilation for the treatment of increased intracranial pressure in rabbits. 1998

A D Watts, and M Eliasziw, and A W Gelb

Department of Anaesthesia, University of Western Ontario, London, Canada.

Using a rabbit model of intracranial hypertension, we studied (a) the additive effect of propofol and hyperventilation (HV) on increased intracranial pressure (ICP), (b) the ICP-lowering effect of additive therapy (i.e., propofol plus HV versus HV plus propofol), and (c) whether combined therapy induced cerebral ischemia. Twenty-three New Zealand White rabbits were studied, of which seven were control animals. The animals were anesthetized with midazolam and fentanyl. An extradural balloon was used to increase ICP to 26+/-2 mm Hg. Elevation of ICP resulted in a >50% reduction in ipsilateral somatosensory evoked potential (SEP) amplitude. The rabbits were then randomized to be treated with propofol followed by HV (Group 1, n = 8) or HV then propofol (Group 2, n = 8). With HV, PaCO2 was reduced from 41+/-2 mm Hg to 27+/-3 mm Hg. In Group 1 rabbits, the ICP decreased with treatment (from 26+/-2 to 12+/-2 mm Hg). The reduction in ICP was significantly greater (P = 0.008) than that in Group 2 rabbits (from 26+/-2 to 16+/-5 mm Hg). In both groups, propofol and HV had an additive effect in reducing ICP. Further, when propofol was used as the initial treatment, there was a significant increase in SEP amplitude that was not apparent in Group 2 rabbits. In conclusion, we found propofol and HV to be additive in the treatment of increased ICP. In animals treated with propofol followed by HV, there was a greater decrease in ICP than in rabbits treated initially with HV and then propofol. CONCLUSIONS We have demonstrated that propofol has a greater effect on increased intracranial pressure than hyperventilation when used as the initial treatment and that the two treatments are additive. Should control of intracranial pressure be required after the administration of propofol, then hyperventilation may be added to the treatment.

UI	MeSH Term	Description	Entries
D007427	Intracranial Pressure	Pressure within the cranial cavity. It is influenced by brain mass, the circulatory system, CSF dynamics, and skull rigidity.	Intracerebral Pressure,Subarachnoid Pressure,Intracerebral Pressures,Intracranial Pressures,Pressure, Intracerebral,Pressure, Intracranial,Pressure, Subarachnoid,Pressures, Intracerebral,Pressures, Intracranial,Pressures, Subarachnoid,Subarachnoid Pressures
D011817	Rabbits	A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes.	Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
D012121	Respiration, Artificial	Any method of artificial breathing that employs mechanical or non-mechanical means to force the air into and out of the lungs. Artificial respiration or ventilation is used in individuals who have stopped breathing or have RESPIRATORY INSUFFICIENCY to increase their intake of oxygen (O2) and excretion of carbon dioxide (CO2).	Ventilation, Mechanical,Mechanical Ventilation,Artificial Respiration,Artificial Respirations,Mechanical Ventilations,Respirations, Artificial,Ventilations, Mechanical
D002545	Brain Ischemia	Localized reduction of blood flow to brain tissue due to arterial obstruction or systemic hypoperfusion. This frequently occurs in conjunction with brain hypoxia (HYPOXIA, BRAIN). Prolonged ischemia is associated with BRAIN INFARCTION.	Cerebral Ischemia,Ischemic Encephalopathy,Encephalopathy, Ischemic,Ischemia, Cerebral,Brain Ischemias,Cerebral Ischemias,Ischemia, Brain,Ischemias, Cerebral,Ischemic Encephalopathies
D005073	Evoked Potentials, Somatosensory	The electric response evoked in the CEREBRAL CORTEX by stimulation along AFFERENT PATHWAYS from PERIPHERAL NERVES to CEREBRUM.	Somatosensory Evoked Potentials,Evoked Potential, Somatosensory,Somatosensory Evoked Potential
D000758	Anesthesia	A state characterized by loss of feeling or sensation. This depression of nerve function is usually the result of pharmacologic action and is induced to allow performance of surgery or other painful procedures.
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
D015742	Propofol	An intravenous anesthetic agent which has the advantage of a very rapid onset after infusion or bolus injection plus a very short recovery period of a couple of minutes. (From Smith and Reynard, Textbook of Pharmacology, 1992, 1st ed, p206). Propofol has been used as ANTICONVULSANTS and ANTIEMETICS.	Disoprofol,2,6-Bis(1-methylethyl)phenol,2,6-Diisopropylphenol,Aquafol,Diprivan,Disoprivan,Fresofol,ICI-35,868,ICI-35868,Ivofol,Propofol Abbott,Propofol Fresenius,Propofol MCT,Propofol Rovi,Propofol-Lipuro,Recofol,2,6 Diisopropylphenol,ICI 35,868,ICI 35868,ICI35,868,ICI35868
D018681	Anesthetics, General	Agents that induce various degrees of analgesia; depression of consciousness, circulation, and respiration; relaxation of skeletal muscle; reduction of reflex activity; and amnesia. There are two types of general anesthetics, inhalation and intravenous. With either type, the arterial concentration of drug required to induce anesthesia varies with the condition of the patient, the desired depth of anesthesia, and the concomitant use of other drugs. (From AMA Drug Evaluations Annual, 1994, p.173)	General Anesthetic,General Anesthetics,Anesthetic, General