Effect of positive-end-expiratory-pressure on right ventricular output in lambs with hyaline membrane disease

Area of Science:

• Neonatal Physiology
• Cardiovascular Research
• Respiratory Medicine

Background:

• Hyaline membrane disease (HMD) is a common respiratory distress in premature infants.
• Positive-end-expiratory-pressure (PEEP) is used to improve oxygenation in HMD.
• The effects of PEEP on fetal circulation, particularly ductal shunting, require further investigation.

Purpose of the Study:

• To investigate the hemodynamic effects of PEEP on fetal circulation in lambs with induced HMD.
• To assess changes in right and left ventricular outputs, pulmonary and systemic blood flows.
• To evaluate blood flow through the ductus arteriosus during PEEP.

Main Methods:

• Hemodynamic parameters were measured in 5 premature lambs with induced HMD.
• Measurements were taken before and during the application of PEEP.
• Cardiac output, blood flows, and ductal shunting were quantified.

Main Results:

• PEEP significantly increased right ventricular output in all lambs.
• Left ventricular output and pulmonary vascular resistance remained unchanged.
• Left-to-right ductus arteriosus flow decreased, especially in lambs with initially large shunts.
• No significant right-to-left ductus arteriosus flow was observed.

Conclusions:

• PEEP favorably impacts right ventricular function and pulmonary blood flow distribution in HMD.
• PEEP may reduce left-to-right shunting through the ductus arteriosus.
• These findings suggest PEEP can be a beneficial respiratory support strategy in neonatal respiratory distress.