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La parakinésie brachiale oscitante
Yawning: its cycle, its role
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Fetal yawning assessed by 3D and 4D sonography
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Le bâillement : de l'éthologie à la médecine clinique
Le bâillement : phylogenèse, éthologie, nosogénie
 Le bâillement : un comportement universel
La parakinésie brachiale oscitante
Yawning: its cycle, its role
Warum gähnen wir ?
 
Fetal yawning assessed by 3D and 4D sonography
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mystery of yawning resolutionmini 

 

mise à jour du
23 septembre 2001
 American Journal of Roentgenology
1988; 150; 209
 Yawning : an early manifestation of vasovagal reflex
Thomas Georges Cronin
St Francis Hospital, Evanston, IL 60202, USA
Chat-logomini
Yawning is defined as "the involuntary act of opening the mouth widely, accompanied by deep inspiration, and frequently stretching of the arme, shoulders, and chest to assist in the inspiratory act followed by relaxation of the muscles invoived, usually performed when sleepy or bored" [1].
 
All my life I have been acutely aware of the yawns of those about me (e.g., audiences lecture, fraternizers at cocktail parties, my wife). It is this cognizance that led to my recognition of yawning as an early sign of a vasovagal reflex or reaction. Noxious stimuli (e.g., needle sticks, contrast media, release of histamine, rectal distension, fear, and other somatic avants) can cause the vagal brainstem nuclei to discharge impulses that lead to acetylcholine-mediated effects on the arterioles and the sinoartrial node, resulting in hypotension and bradycardia. The potential seriousness of these reactions is well documented in the medical literature, particularly for patients who have underlying coronary and cerebral vascular disease [2].
 
Many signs and symptoms of vasovagal reflex and reaction have been reported: apprehension, restlessness, dizziness, faintness, intestinal cramping, nausea, salivation, sweating, palpitation, dyspnea, syncope, and unconsciousness [3].
 
I have noticed that in most of the vasovagal reflexes or reactions encounter, yawning is the first manifestation.
 
According to definition, yawning is caused by sleepiness or boredom, but I do not think that patients who are undergoing needle sticks, angiography, or barium enemas are ever bored, and their premedication probably does not make them sleepy. Premedication may put them to sleep, but there is no middle ground. So, if a patient begins yawning during a barium enema or a breast localization, place the patient supine, measure the pulse and blood pressure, elevate the patient's legs or place the patient in the Trendelenburg position, open the IV Unes, and have the atropine ready. If measures to expand fluid volume are not successful (and beware of patients who are in heart failure), 0.6-0.8 mg of IV atropine usually will reverse the reaction [4].
 
References
  1. Blakinstons Gould medical dictionary, 4th ed. New York: McGraw-Hill, 1979:1491
  2. Newton TH, Potts DG, eds. Radiology of the skull and brain, vol. 2, book 1: Angiography. St. Louis: Mosby, 1974:1034
  3. Andrews EJ. The vagus reaction as a possible cause of severe complications of radiologic procedures. Radiology 1976;121:1-4
  4. Kadir S. Diagnostic angiography. Philadelphie: Saunders, 1976:688-689
  5. Askenasy JJ Is yawning an arousal defense reflex ?