Saudi Journal of Gastroenterology

ARTICLES
Year
: 1998  |  Volume : 4  |  Issue : 2  |  Page : 81--89

Swallowing-induced cardio-respiratory responses in man


Mansour Abdul Gadir Ballal, Paul Anthony Sanford 
 Department of Physiology, College of Medicine, King Saud University, Riyadh, Saudi Arabia

Correspondence Address:
Paul Anthony Sanford
Department of Physiology, College of Medicine, King Saud University, P.O. Box 2925, Riyadh 11461
Saudi Arabia

Swallowing transiently increases heart rate. One of the authors developed pronounced bradycardia while breath holding, particularly after an expiration. The objective, therefore, was to study his cardiac responses during swallowing as pronounced bradycardia developed. When, after a maximum inspiration (supine), the heart rate slowly fell below 50 beats min«SQ» well-defined P waves (lead II) disappeared. By swallowing 6 times on command after the P waves disappeared his heart rate increased immediately (68 ± I beats min-«SQ»; n=6). P waves with similar morphology to those pre-swallowing were recorded 0.7 ± 0.1 s (n=6) after the first swallow. He continued breath holding after swallowing. P waves again disappeared, although at faster heart rates (57 ± I beats min«SQ»; n=6). Furthermore, well-defined P waves were observed after the second disappearance at heart rates within the range 30-40 beats min«SQ». Small amplitude P waves continued to be recorded from lead I with P wave disappearance in lead II, suggesting a pacemaker shift, although not to the av node. Autonomic nerves can shift the dominant pacemaker within the sa node. The present report indicates that increased vagal tone may be rapidly reversed by swallowing.


How to cite this article:
Ballal MA, Sanford PA. Swallowing-induced cardio-respiratory responses in man.Saudi J Gastroenterol 1998;4:81-89


How to cite this URL:
Ballal MA, Sanford PA. Swallowing-induced cardio-respiratory responses in man. Saudi J Gastroenterol [serial online] 1998 [cited 2019 Aug 23 ];4:81-89
Available from: http://www.saudijgastro.com/article.asp?issn=1319-3767;year=1998;volume=4;issue=2;spage=81;epage=89;aulast=Ballal;type=0