Evaluation of the premature infant at risk for postoperative complications.

We reviewed anaesthetic records of 35 infants with a history of prematurity, who presented for elective herniorrhaphy. We applied a scoring system to help evaluate risk of postoperative complications. Six patients experienced postoperative complications. All six patients had a score of five or more and gave history of either apnoea or a history of moderate bronchopulmonary dysplasia. A preoperative history of apnoea and/or moderate bronchopulmonary dysplasia appear to be valuable markers for postoperative complications. A conceptual age of 40 weeks is an acceptable lower limit of age providing there is no history of apnoea or pulmonary disease.

Energy metabolism in anesthetized children with burns.

Energy dynamics in 10 burned children were studied to determine cause and effect relationships between rates of heat production, heat loss and plasma catecholamine concentrations when thermoregulatory responses were depressed by methoxyflurane anesthesia. Rapid cooling of the burned children was due to increased heat loss during the period of anesthesia. Heat production increased significantly, although not enough to counterbalance the increased heat loss reflecting a block in central thermoregulation by general anesthesia. Mean plasma catecholamine concentrations decreased during general anesthesia as compared with baseline values. Heat production attempted to track heat loss during a period in which plasma catecholamine levels declined. An increased rate of heat loss is concluded to be primary stimulus for increased metabolic acitvity after thermal injury.

Sickling dynamics of red blood cells and other physiologic studies during anesthesia.

Nineteen patients with electrophoretically proven sickle cell diseases were studied prospectively at intervals, using halothane, methoxyflurane, cyclopropane, and fluroxene. Simultaneous venous and arterial samples were taken from the same arm in heparinized syringes at the sampling intervals and analyzed for blood gases, hematocrit, and percent sickle cells. Measurements of blood pressure, pulse, temperature, tidal volume, minute ventilation, and other significant data were recorded. There were no anesthetic deaths, and the morbidity seen was an extension of pre-existing pathology. Sickling was found to be greatly reduced in both arterial and venous blood during anesthesia, with the greater reduction in venous blood. Following anesthesia, sickling returned toward, but often did not reach, pre-anesthetic levels. Blood-gas measurements reflected the slightly increased ventilation and considerably increased inspired oxygen during anesthesia. Other measurements were not remarkable.