The effect of mechanical ventilation modes on salivary cortisole levels in premature babies receiving respiratory support

Introduction and Aim: Since the respiratory system of prematurely born newborns is not sufficiently developed, respiratory failure is common in these infants and mechanical ventilation treatment may be required. Pain and stress in babies during this practice is one of the conditions that can lead to negative consequences in the neurological development of these babies. One of the important non-invasive tests showing the presence of stress is salivary cortisol level. In this study, we aimed to examine the relationship between mechanical ventilation modes and stress levels by measuring the salivary cortisol level of the cases. Method: The study was carried out in Çukurova University Faculty of Medicine Neonatal Intensive Care Units. The study group consisted of 65 premature infants who were followed up for prematurity and received respiratory support for various reasons, and 43 premature infants who did not need respiratory support in room air constituted the control group. Just before sampling, pulse, body temperature, respiratory rate, oxygen saturation, systolic-diastolic blood pressure values were recorded. NIPS scale was used to evaluate the pain of infants. To determine the stress level, salivary cortisol level was studied. Saliva samples were taken from the babies included in the study on the postnatal 4th day between 07.00-09.00 in the morning and 22:00-23.00 in the evening by the same health personnel. Results: 32 of the babies in the study group were girls and 33 of them were boys, and 23 of the babies in the control group were girls and 20 were boys. There was no statistical difference between the mean birth week and birth weight of the babies included in the study. It was determined that the mean NIPS Score, mean heart rate and mean respiratory rate of the babies in the study group were significantly higher than the babies in the control group (p<0.001; p<0.001; p<0.001, respectively). The morning and evening salivary cortisol levels of the babies in the study group were found to be significantly higher than the babies in the control group (p<0.001; p<0.001, respectively). Among the babies in the study group, the mean morning cortisol values of the babies who underwent invasive mechanical ventilation were 12.46±5.3 ng/ml, the evening cortisol values were 12.0±5.2 ng/ml, and the morning cortisol values of the babies who were applied non-invasive mechanical ventilation were 4.57 ±2.7 ng/ml, evening cortisol values were 4.41±2.7 ng/ml. Cortisol levels of infants who underwent invasive mechanical ventilation were found to be higher than morning and evening cortisol values of infants who received non-invasive mechanical ventilation (p<0.001; p<0.001, respectively). In the invasive mechanical ventilation group; There was no significant difference between morning and evening cortisol values of babies followed up with PSV and SIPPV mechanical ventilation modes. (p=0.402, respectively; p=0.391). It was determined that the morning and evening cortisol values of the babies followed up in the nSIMV mode with non-invasive mechanical ventilation were higher than the babies followed up with the nCPAP mode (p=0.031; p=0.038, respectively). Conclusion: The fact that the ventilated infants in this study had significantly higher salivary cortisol levels than the control group indicates that pain and stress are higher in these infants. For this reason, we think that physicians and nurses have important duties for the pain and stress management of infants undergoing mechanical ventilation. Keywords: Neonatal, Cortisol, Invasive, Noninvasive