Diving bradycardia in man.

Factors affecting the recovery from diving bradycardia in the frog.

Heart rate regulation and extreme bradycardia in diving emperor penguins.

To investigate the diving heart rate (f(H)) response of the emperor penguin (Aptenodytes forsteri), the consummate avian diver, birds diving at an isolated dive hole in McMurdo Sound, Antarctica were outfitted with digital electrocardiogram recorders, two-axis accelerometers and time depth recorders (TDRs). In contrast to any other freely diving bird, a true bradycardia (f(H) significantly <f(H...

The diving reflex: bradycardia during cold ocular irrigation.

R E P L Y I thank Drs. Mezon and Badner for their thoughts on the case, but I don't think diminished gas flow in the face o f increased minute volume explains the rapid hypercarbia. Firstly, within 15 min the PETCO 2 increased from 32 to 45 mmHg without alteration o f ventilation or fresh gas flow. Secondly, I have never seen a doubling o f PETCO 2 simply by increasing the minute volume without...

Bradycardia in a Man With Acute Chest Pain

Blood pressure is 80/60 mm Hg; heart rate, 50 beats per minute; and respiration rate, 26 breaths per minute. Oxygen saturation is normal, and the lung fields are clear. An ECG rhythm strip in lead II (A) shows a regular narrow QRS-complex rhythm; in addition, in this rhythm strip, the ST segment is elevated with a concave morphology. The patient is given a normal saline bolus and 1 mg of atropi...

Deep-diving sea lions exhibit extreme bradycardia in long-duration dives.

Heart rate and peripheral blood flow distribution are the primary determinants of the rate and pattern of oxygen store utilisation and ultimately breath-hold duration in marine endotherms. Despite this, little is known about how otariids (sea lions and fur seals) regulate heart rate (fH) while diving. We investigated dive fH in five adult female California sea lions (Zalophus californianus) dur...