Breath holding time is the time taken by the subject to hold his breath as long as he can. During voluntary breath holding, tissues continue to utilize oxygen and liberate carbon dioxide. Therefore during breath holding arterial pO2 falls and pCO2 rises. Since both these factors are powerful respiratory stimulants, a point is reached where the respiratory drive becomes so strong that the person...

OBJECTIVE While there is recent interest in using repeated deep inspiratory breath-holds, or prolonged single breath-holds, to improve radiotherapy delivery, breath-holding has risks. There are no published guidelines for monitoring patient safety, and there is little clinical awareness of the pronounced blood pressure rise and the potential for gradual asphyxia that occur during breath-holding...

Background: Breath holding spells (BHS) are paroxysmal events with apnea and postural tone with Electrocardiography (ECG) abnormality and epilepsy status reports. The study aimed to compare the ECG parameters’ in epilepsy and breath-holding children compared with healthy children. Materials and Methods: </st...

Blood oxygen level dependent (BOLD) contrast is influenced by some physiological factors such as blood flow and blood volume that can be a source of variability in fMRI analysis. Previous studies proposed to use the cerebrovascular response data to normalize or calibrate BOLD maps in order to reduce variability of fMRI data both among brain areas in single subject analysis and across subjects. ...

The effect of altitude and acetazolamide on breath holding was studied in 20 individuals. Breath holding time was reduced progressively during ascent. There was an additional reduction in the acetazolamide group at low but not at high altitude. The initial difference between the two groups may have been related to a lower CSF pH when on acetazolamide. At high altitude the finding of similar bre...

QUESTION I have children in my clinic who experience seizurelike episodes in which they cry and hold their breath to the point of cyanosis and loss of consciousness. Their examination or investigation findings are normal and referral to a pediatric specialist results in no further investigation. Are breath-holding spells common, and what type of investigation is needed? ANSWER A breath-holdin...

BACKGROUND AND PURPOSE Recently, noninvasive MRI methods have been developed that are now capable of detecting and mapping regional hemodynamic responses to various stress tests, which involve the use of vasoactive substances such as acetazolamide or inhalation of carbon dioxide. The aim of this study was to assess regional cerebral blood oxygenation changes during breath holding at 1.5 T. ME...