Respiratory and Hemodynamic Adjustment During Head Out Water Immersion

Abstract

In this study, the effect of head out water immersion on cardiopulmonary function was investigated in six healthy male subjects. Resistance to breathing, pulmonary capillary volume, and cardiac output increased during immersion. Constancy was observed for shunt perfusion, diffusing capacity, and diffusing capacity of the membrane. Carbon monoxide transfer factor (T CO) in relation to alveolar volume (VA) increased significantly. Due to nonuniform distribution of ventilation during immersion, Pa02 dropped during immersion while AaDO2 increased significantly. The described changes are due to the blood shift and hydrostatic pressure during immersion to the neck. The functional changes counteract each other, partly worsening and partly improving cardiopulmonary function. However, in summary, respiratory and circulatory function are slightly reduced during head out water immersion.

Breath-Hold Diving

“…Cardiac diastolic filling may increase by 180 to 250 mL, and pulmonary capillary blood volume may increase by 51 to 200 mL. [90][91][92][93] These hemodynamic changes, which are enhanced by immersion in cold water, may contribute to pulmonary edema in swimmers and divers (see Chapter 25). [94][95][96] Typically, the symptoms, including shortness of breath and coughing, resolve as soon as the diver gets out of water; symptoms may become more frequent with advanced age 97 and in swimmers with subnormal baseline spirometry values.…”

Central chemosensitivity is augmented during 2 h of thermoneutral head‐out water immersion in healthy men and women

“…Carbon dioxide (CO 2 ) retention is defined as an increase in arterial CO 2 content above resting values (Lanphier & Bookspan, 1999). CO 2 retention occurs during water immersion (Bennett & Elliott, 1975;Cherry et al, 2009;Lanphier & Bookspan, 1999;Löllgen, von Nieding, & Horres, 1980;Mummery et al, 2003;Pendergast & Lundgren, 2009;Pendergast, Moon, Krasney, Held, & Zamparo, 2015;Sackett, Schlader, Sarker, Chapman, & Johnson, 2017;Salzano, Camporesi, Stolp, & Moon, 1984;Warkander, Norfleet, Nagasawa, & Lundgren, 1990), which increases the risk of CO 2 toxicity (Bennett & Elliott, c 2018 The Authors. Experimental Physiology c 2018 The Physiological Society 1975; Lanphier & Bookspan, 1999;Warkander et al, 1990).…”

Static respiratory muscle work during immersion with positive and negative respiratory loading

“…It is possible that the EELV is defended in response to a volume-dependent reflex or due to changes in respiratory comfort (perhaps via proprioceptive feedback) encountered at high and low lung volumes. At low lung volumes, expiratory airway resistance is substantially elevated (4,11,13), and the choice of the EELV may represent a compromise that attempts to minimize total respiratory work, in the face of conflicting static and flow-resistive respiratory work changes (13) encountered during tidal breathing at low lung volumes.…”

“…breathing apparatus; lung centroid pressure; pressure breathing; pulmonary mechanics; static loading; work of breathing HYPERBARIC IMMERSED EXERCISE elevates the work of breathing and is frequently accompanied by dyspnea, which is often beyond that which may be explained on the basis of increased gas density alone (6,20,23). Upright immersion imposes a pressure imbalance on the respiratory system, similar to that seen with negative-pressure breathing (1,8,19), which results in elevated elastic work (7,13,17), elevated flow-resistive work (7,13), and increased pulmonary resistance (4,11,12). Each of these perturbations, on their own, may account for dyspnea during immersed hyperbaric exercise.…”