The pediatric fiberoptic bronchoscope can be of invaluable help in this regard. The cardiac output is restored by ensuring appropriate rewarming, adequately filling the heart, and often by providing some inotropic support. The infusate temperature is maintained no higher than 10 C over the venous return temperature with a maximum temperature of 42 C in order to avoid rapid rewarming. At a rectal temperature of 32 C, arterial blood gases, electrolytes, hematocrit, calcium, and glucose are checked and adjusted accordingly. Adequate filling of the heart is provided by removing the superior vena cava cannula and the air needle-vent, and then by progressively decreasing the amount of cardiopulmonary bypass support.
Volume is adjusted according to the monitored filling pressures and the distention of the heart.
Deep hypothermic circulatory arrest provides excellent exposure in small hearts by eliminating the need for multiple cannulae and blood from the operative field. The safe duration of the circulatory arrest period is not known, but is likely related to the underlying diagnosis, age of the patient, the pH management strategy, the length of time required to perform the repair, and the presence of aorto-pulmonary collaterals. Precooling Period . Although the current technique of deep hypothermic circulatory uses core cooling as the primary method of cooling, some spontaneous surface cooling starts during the induction of general anesthesia and the placement of monitoring lines. In addition, antibiotics, heparin, sodium bicarbonate, mannitol, solumedrol, and Regitine are added according to Table .