Biomedical subjects

C R Shivpuri

Publications and source records attributed to C R Shivpuri.

3 recordsLinked to original sources

PubMed1984

Decrease in airway pressure during high-frequency jet ventilation in infants with respiratory distress syndrome.

Using a crossover study design, we compared a system of high-frequency jet ventilation with appropriate humidification to pressure-limited conventional ventilation in 12 preterm infants with a birth weight of 1.9 +/- 0.6 kg and gestational age of 32 +/- 2 weeks who had severe respiratory distress syndrome. After a control period of conventional ventilation, high-frequency jet ventilation was administered for 1 to 3 hours at a constant rate (250/min) and inspiratory to expiratory time (1:3 or 1:4) in the same fraction of inspired oxygen as during conventional ventilation. Average peak inspiratory pressure decreased from 29 +/- 3 cm H2O during conventional ventilation to 20 +/- 4 cm H2O during high-frequency jet ventilation (P less than 0.001), whereas positive end expiratory pressure was unchanged, resulting in a reduction in mean airway pressure from 14 +/- 3 to 10 +/- 2 cm H2O (P less than 0.001). There was a simultaneous decrease in PaCO2 (39 +/- 4 to 34 +/- 4 mm Hg, P less than 0.01), but PaO2 did not change. These data indicate that short-term high-frequency jet ventilation maintains gas exchange in infants with respiratory distress syndrome despite a lower PIP and Paw, and results in smaller airway pressure swings than during conventional ventilation. Thus, high-frequency jet ventilation may offer hope for reducing barotrauma in this population.

Blood Gas Analysis↗

PubMed1984

Transcutaneous oxygen tension during nonnutritive sucking in preterm infants.

The effects of nonnutritive sucking on transcutaneous oxygen tension, heart rate, and respiratory rate were studied sequentially in 14 sleeping preterm infants breathing room air. Transcutaneous oxygen tension increased during nonnutritive sucking in infants between 32 and 35 weeks postconceptional age, but not in those between 36 and 39 weeks. This response was not associated with a change in respiratory rate or sleep state, although heart rate tended to increase. These data offer further support for the beneficial effects of nonnutritive sucking in preterm infants.

Female↗

PubMed1983

Decreased ventilation in preterm infants during oral feeding.

As respiratory difficulty may accompany nipple feeding in preterm neonates, we studied the effect of oral feeding on ventilation in 23 preterm infants. The infants composed two groups based on their postconceptional age at the time of study: Group A comprised 12 infants 34 to 35.9 weeks of age, and group B, 11 infants 36 to 38 weeks. Ventilation was measured via a nasal mask pneumotachometer, and sucking pressure via a nipple that also permitted milk delivery; transcutaneous PO2 and PCO2 were continuously monitored. The feeding pattern comprised an initial period of continuous sucking of at least 30 seconds, followed by intermittent sucking bursts for the remainder of the feed. When compared with an initial semi-upright control period, minute ventilation (V1) during continuous sucking fell by 52 +/- 6% (P less than 0.001) and 40 +/- 2% (P less than 0.001) in groups A and B, respectively. This was the result of a decrease in respiratory frequency and tidal volume and was associated with a fall in TcPO2 of 13 +/- 4 mm Hg (P less than 0.01) in group A and 10 +/- 2 mm Hg (P less than 0.01) in group B. During intermittent sucking, V1 and TcPO2 recovered partially only in the more mature infants (group B). At the end of the feed, TcPCO2 have risen by 3 +/- 1 mm Hg (P less than 0.001) in group A and by 2 +/- 2 mm Hg (P less than 0.05) in group B. Thus oral feeding results in an impairment of ventilation during continuous sucking and the subsequent recovery during intermittent sucking is dependent on postconceptional age.

Drinking↗