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A Peliowski

Publications and source records attributed to A Peliowski.

22 records · Page 2Linked to original sources

The effects of negative pressure external high frequency oscillation on cerebral blood flow and cardiac output of the monkey.

The cerebral and systemic hemodynamic effects of negative pressure ventilation by external high frequency oscillation, utilizing a thoracoabdominal chamber, were investigated in six healthy adult monkeys. Cardiac output and cerebral blood flow were compared on external high frequency oscillation and conventional, positive pressure, mechanical ventilation in each animal. Cardiac output was measured by thermodilution and cerebral blood flow was measured by the intraarterial Xenon133 clearance technique. Oxygen delivery and consumption and systemic and pulmonary vascular resistances were calculated. There was no significant difference between the two ventilatory modes for any of these variables. Cardiac index on conventional mechanical ventilation was 2.87 +/- 0.39 1 X min-1 X m-2 (mean +/- SD) and on external high frequency oscillation was 2.96 +/- 0.87 1 X min-1 X min-2. Cerebral blood flow was 43.9 +/- 9.1 ml X 100 g-1 X min-1 on conventional and 39.0 +/- 9.0 ml X 100 g-1 X min-1 on external high frequency ventilation. External high frequency oscillation is not associated with any adverse cardiovascular or cerebrovascular effects and could be introduced for short-term human trials.

Animals↗

External high frequency oscillation in cats. Experience in the normal lung and after saline lung lavage.

In an effort to develop a method of assisted ventilation that would avoid endotracheal intubation, 11 anesthetized, paralyzed, nonintubated adult mongrel cats with normal lungs were externally oscillated by means of a thoracoabdominal chamber connected to a vacuum source and a high frequency oscillator. Chamber pressure was adjusted to the desired negative pressure using the vacuum source, and the animal was then oscillated above and below this pressure. The lowest PaCO2 and AaPO2 were observed at 3 Hz. Tidal volume (VT) fell (p less than 0.001) with increases in frequency, and lung volume (VL) rose with increased negative chamber pressure (p less than 0.001). In 11 additional tracheostomized cats, a stiff lung was created by repeated saline lung lavage. External high frequency oscillation (EHFO), using pressures comparable to those used for conventional mechanical ventilation (CMV), was associated with a significant increase in PaO2 (p less than 0.001), and a significant fall in AaPO2 (p less than 0.01) compared with that during CMV. Lung volume was significantly higher during EHFO (p less than 0.001) and, as in the normal lung, VT fell with increasing frequencies to 15 Hz (p less than 0.001). There were no significant frequency-dependent variations in gas exchange or VL. An increasingly negative mean chamber pressure was associated with a significant increase in PaO2 (p less than 0.05) and VL(p less than 0.005) and a significant decrease in PaCO2 (p less than 0.025).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Serum zinc, copper, and selenium concentrations in preterm infants receiving enteral nutrition or parental nutrition supplemented with zinc and copper.

Fifteen enterally fed preterm infants not receiving additional trace element supplements and 22 preterm infants receiving total or partial parenteral nutrition supplemented with zinc at 350 micrograms/kg/day and copper at 20 micrograms/kg/day were examined 1, 7, 14, 21, and 28 days after birth. Mean serum Zn concentrations in the parenteral group remained relatively constant and were significantly higher (P less than 0.01) at day 21 than the value for the enteral group. In contrast, a significant decline in mean serum Zn concentrations occurred between days 1 and 21 in the enteral group. The mean serum Cu concentrations in the parenteral group rose during the first week, and were significantly higher at days 14 and 21 than corresponding values in the enteral group. This trend did not result from copper supplementation alone but was also attributed to the presence of ceruloplasmin in blood transfusions. Mean serum Se concentrations did not change significantly, either between or within the two groups, except during the first week, at which time levels rose in the parenteral group. The addition of Zn, Cu, and probably of Se to parenteral infusates, allows the maintenance of appropriate serum values.

Ceruloplasmin↗