CV Review, Essentials, Develop. Physiol., Dr. D. Penney



Table 1.04 - Human Diving Response: Components and Characteristics.

Oxygen conservation for aerobic tissues is paramount! Lung, blood, tissue oxygen used; results in decreased saturation of hemoglobin, and hypercapnia (respiratory acidosis)
Apnea/face immersion; facial./glottal receptors initiate response, intensified by peripheral chemo-receptors Decrease in overall metabolism, heat production, decrease in body temperature
Increased peripheral resistance and arterial B.P. due to intense peripheral sympathetic tone; directs blood to most critical organs Increase in insulation due to peripheral vasoconstriction
Bradycardia due to intense vagal tone (withdrawal of sympathetic tone?); hypertensive response may contribute; abolished with atropine, intensified by cold water; sinus arrhythmia Anaerobic metabolism in skeletal muscle and other peripheral tissues, release of lactate and development of metabolic acidosis (oxygen debt)


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