Biomaterial Database

Impairment of cerebral perfusion during obstructive sleep apneas. 1994

E M Bålfors, and K A Franklin

Department of Anesthesia, University Hospital of Northern Sweden, Umeå.

Cerebral circulation was studied in six patients with obstructive sleep apnea (OSA) by transcranial Doppler. Cerebral blood flow velocity (CBFV), pulsatility index (Pi), intra-arterial radial blood pressure, transcutaneous blood gases, and respiration were recorded during sleep with or without apneas. There was a concomitant increase of mean arterial pressure (Pa) and CBFV by 11 +/- 6% (p < 0.001) and 15 +/- 6% (p < 0.001) compared with baseline at 5.1 +/- 2.4 and 5.3 +/- 2.6 s, respectively, after apnea termination. Pa and CBFV decreased to a minimum of -8 +/- 2% (p < 0.001) and -23 +/- 8% (p < 0.001), respectively, below baseline at 19.8 +/- 5.0 and 19.4 +/- 4.5 s after apnea. Values returned to baseline within 60 s, except during repetitive apneas, which were associated with prolonged periods of reduced Pa and CBFV. Pi changed inversely to CBFV and rose to 34 +/- 15% (p < 0.001) above baseline 19.5 +/- 5.5 s after the end of apnea because of a decrease in diastolic CBFV. There was a close correlation between Pa and CBFV (r = 0.67, p < 0.001), indicating that cerebral autoregulation is insufficient to protect the brain from rapid systemic pressure changes in OSA. The findings suggest that apneas during sleep are associated with profound changes in cerebral blood flow. Apnea-induced hypoxemia combined with reduced cerebral perfusion may predispose to nocturnal cerebral ischemia in patients with OSA.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D009765	Obesity	A status with BODY WEIGHT that is grossly above the recommended standards, usually due to accumulation of excess FATS in the body. The standards may vary with age, sex, genetic or cultural background. In the BODY MASS INDEX, a BMI greater than 30.0 kg/m2 is considered obese, and a BMI greater than 40.0 kg/m2 is considered morbidly obese (MORBID OBESITY).
D001783	Blood Flow Velocity	A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.	Blood Flow Velocities,Flow Velocities, Blood,Flow Velocity, Blood,Velocities, Blood Flow,Velocity, Blood Flow
D002560	Cerebrovascular Circulation	The circulation of blood through the BLOOD VESSELS of the BRAIN.	Brain Blood Flow,Regional Cerebral Blood Flow,Cerebral Blood Flow,Cerebral Circulation,Cerebral Perfusion Pressure,Circulation, Cerebrovascular,Blood Flow, Brain,Blood Flow, Cerebral,Brain Blood Flows,Cerebral Blood Flows,Cerebral Circulations,Cerebral Perfusion Pressures,Circulation, Cerebral,Flow, Brain Blood,Flow, Cerebral Blood,Perfusion Pressure, Cerebral,Pressure, Cerebral Perfusion
D006439	Hemodynamics	The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.	Hemodynamic
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000208	Acute Disease	Disease having a short and relatively severe course.	Acute Diseases,Disease, Acute,Diseases, Acute
D012891	Sleep Apnea Syndromes	Disorders characterized by multiple cessations of respirations during sleep that induce partial arousals and interfere with the maintenance of sleep. Sleep apnea syndromes are divided into central (see SLEEP APNEA, CENTRAL), obstructive (see SLEEP APNEA, OBSTRUCTIVE), and mixed central-obstructive types.	Apnea, Sleep,Hypersomnia with Periodic Respiration,Sleep-Disordered Breathing,Mixed Central and Obstructive Sleep Apnea,Sleep Apnea, Mixed,Sleep Apnea, Mixed Central and Obstructive,Sleep Hypopnea,Apnea Syndrome, Sleep,Apnea Syndromes, Sleep,Apneas, Sleep,Breathing, Sleep-Disordered,Hypopnea, Sleep,Hypopneas, Sleep,Mixed Sleep Apnea,Mixed Sleep Apneas,Sleep Apnea,Sleep Apnea Syndrome,Sleep Apneas,Sleep Apneas, Mixed,Sleep Disordered Breathing,Sleep Hypopneas
D017585	Ultrasonography, Doppler, Transcranial	A non-invasive technique using ultrasound for the measurement of cerebrovascular hemodynamics, particularly cerebral blood flow velocity and cerebral collateral flow. With a high-intensity, low-frequency pulse probe, the intracranial arteries may be studied transtemporally, transorbitally, or from below the foramen magnum.	Doppler Sonography, Transcranial,Doppler Transcranial Sonography,Doppler Transcranial Ultrasonography,Doppler Ultrasonography, Transcranial,Sonography, Transcranial Doppler,Ultrasonography, Transcranial Doppler,Neurosonology,Sonography, Doppler Transcranial,Transcranial Doppler Sonography,Transcranial Doppler Ultrasonography,Transcranial Sonography, Doppler,Transcranial Ultrasonography, Doppler,Ultrasonography, Doppler Transcranial,Neurosonologies