The Effect of Positions on Physiological Parameters of Preterm Neonates Receiving Mechanical Ventilation

Preterm neonates face various adaptation problems starting from their birth due to their underdeveloped organ systems. A significant portion of preterm neonates need advanced care due to respiratory system problems, especially due to insufficient adaptation of the respiratory systems to the extrauterine environment, and the majority of them require mechanical ventilation. For these reasons, it is a priority to restore the respiratory functions of preterm neonates. To ensure the functionality of body systems in the developmental care of neonates in this process, the method of neonatal positioning, which is one of the individualized supportive developmental care methods, is necessary. The primary goal of positioning in neonatal intensive care units is to reduce the effects of pain and environmental stimuli caused by interventions for treatment and care for neonates and to help them cope with stress by maintaining their posture. Developmental positioning practices aim to support neuromotor development and minimize pain by maintaining the comfortable position of the neonate surrounded by the midline. The positioning has been shown to significantly affect the respiratory systems of neonates and affect oxygenation and lung ventilation. Change of position is also crucial in physiological and neurodevelopmental aspects for neonates receiving mechanical ventilation. It is important to reposition neonates since they remain in the same position all the time, which may lead to the accumulation of secretions and the formation of pressure sores. Positioning is an important factor in the development of neonates; therefore, correct positioning is critical for the comfort of neonates in the short and long term. Giving and maintaining a suitable position for neonates is an important nursing intervention. With developmentally supportive positioning applications, infants are positioned in supine, prone, lateral (right/left) and quarter prone positions. Considering these positions one by one, the supine position, where nursing care can be provided more easily, increases the sensory-motor activities of the neonate and reduces the energy consumption resulting from the infant's activities. Neonatal intensive care units mostly place neonates in the prone position since it has a positive effect on breathing, sleep quality, and behavioral conditions. The prone position makes the newborn feel safer with the adjustments made in the extrauterine environment. The lateral (right/left) position is one of the positions reducing the extensor effects of gravity and supporting the midline orientation of the hands and feet along with the head, which can be preferred in cases where the prone position cannot be used. In the quarter-prone position, neonates are placed in a functional position similar to the prone position but with one side of the body slightly elevated to encourage the synchronous movement of the thoracic and abdominal respiratory muscles. It has been observed that the quarter prone position provides similar advantages as the prone position by increasing lung compliance, tidal volume, respiratory rhythm, and oxygenation during sleep. Preterm neonates are placed in these positions in daily routine care of neonatal intensive care units.

The review of the relevant literature reveals studies comparing different groups regarding the positioning of preterm neonates receiving mechanical ventilators in the neonatal intensive care unit. These studies have mainly focused on the effect of supine, prone, right lateral and left lateral positions in preterm neonates receiving mechanical ventilation.

There is no study collectively comparing supine, prone, right lateral, left lateral and quarter prone positions used during daily routine care of preterm neonates receiving mechanical ventilation, which was aimed in this study. In this context, it was considered that evaluating the effect of supine, prone, right lateral, left lateral and quarter prone positions routinely used in the neonatal intensive care unit on the physiological parameters of preterm neonates receiving mechanical ventilation (oxygen saturation, heart rate, respiratory rate) and determining which position is more effective for preterm infants will contribute to the literature and guide the care provided by neonatal nurses.

Place And Tıme Of The Study:

This study was planned to be conducted in the Neonatal Intensive Care Unit of the University of Health Sciences Etlik Zubeyde Hanim Gynecology Training and Research Hospital between June 2022 and June 2023 after obtaining the necessary institutional and ethical committee approvals.

Hypotheses Of The Study:

Hypothesis 0(H0): There is no difference between prone, supine, right lateral, left lateral and quarter prone positioning of preterm infants in terms of physiological parameters of the infant.

Hypothesis 1.1(H1.1): Supine positioning of preterm infants is more effective in physiological parameters than other positions.

Hypothesis 1.2(H1.2): Prone positioning of preterm infants is more effective in physiological parameters than other positions.

Hypothesis 1.3(H1.3): Left lateral positioning of preterm infants is more effective in physiological parameters than other positions.

Hypothesis 1.4(H1.4): Right lateral positioning of preterm infants is more effective in physiological parameters than other positions.

Hypothesis 1.5(H1.5): Quarter prone positioning of preterm infants is more effective in physiological parameters than other positions.

Unıverse And Sample Of The Study:

The universe of the study comprised preterm neonates receiving mechanical ventilation in the Neonatal Intensive Care Unit of the University of Health Sciences Etlik Zubeyde Hanim Gynecology Training and Research Hospital. Multi-group comparisons were planned in the analysis of the hypotheses of the study and the sample size calculated according to the statistical method to be used was taken as a basis.

Using "G."Power version 3.1.9.2" software, the sample size was calculated at a confidence level of 95%. As a result of the analysis, α=0.05, the standardized effect size was calculated from a similar study conducted in this field. The minimum sample size was estimated as 8 subjects for each group when the effect size was taken as 0.72 (high), with theoretical power of 0.80. As evaluations will be carried out in 5 groups in this study, the minimum sample size was found to be 40.

Inclusion criteria

• A gestational age of 28-36 weeks ,
• Receiving mechanical ventilation (non-intubated),
• Volunteer consent of the parents of the preterm neonate to participate in the study.

Exclusion criteria

• Receiving mechanical ventilation and being intubated,
• Having any congenital and genetic disorders,
• Having a health problem that prevents positioning,
• Having a chest tube, umbilical catheter or PICC line,
• Receiving continuous sedative therapy, anticonvulsive therapy and cardiac drug therapy,
• Frequent changes in mechanical ventilator settings,
• A feeding frequency of more than three hours.