Exerted force on the face mask in preterm infants at birth is associated with apnoea and bradycardia.

BACKGROUND: During stabilisation of preterm infants at birth, a face mask is used to provide respiratory support. However, application of these masks may activate cutaneous stretch receptors of the trigeminal nerve, causing apnoea and bradycardia. This study investigated the amount of force exerted on the face mask during non-invasive ventilation of preterm infants at birth and whether the amount of exerted force is associated with apnoea and bradycardia. METHODS: A prospective observational study was performed in preterm infants born <32 weeks of gestation who were stabilised at birth. During the first 10 minutes of respiratory support, we measured breathing and heart rate as well as the amount of force exerted on a face mask using a custom-made pressure sensor placed on top of the face mask. RESULTS: Thirty infants were included (median (IQR) gestational age(GA) 28+3 (27+0-30+0) weeks, birthweight 1104 (878-1275) grams). The median exerted force measured was 297 (198-377) grams, ranging from 0 to 1455 grams. Significantly more force was exerted on the face mask during positive pressure ventilation when compared to CPAP (410 (256-556) vs 286 (190-373) grams, p = 0.009). In a binary logistic regression model, higher forces were associated with an increased risk of apnoea (OR = 1.607 (1.556-1.661), p < 0.001) and bradycardia (OR = 1.140 (1.102-1.180), p < 0.001) during the first 10 minutes of respiratory support at birth. CONCLUSION: During mask ventilation, the median exerted force on a face mask was 297 grams with a maximum of 1455 grams. Higher exerted forces were associated apnoea and bradycardia during the first 10 minutes of respiratory support at birth.

The effect of implementing an automated oxygen control on oxygen saturation in preterm infants.

OBJECTIVE: To evaluate the effect of implementing automated oxygen control as routine care in maintaining oxygen saturation (SpO2) within target range in preterm infants. METHODS: Infants <30 weeks gestation in Leiden University Medical Centre before and after the implementation of automated oxygen control were compared. The percentage of time spent with SpO2 within and outside the target range (90-95%) was calculated. SpO2 values were collected every minute and included for analysis when infants received extra oxygen. RESULTS: In a period of 9 months, 42 preterm infants (21 manual, 21 automated) were studied. In the automated period, the median (IQR) time spent with SpO2 within target range increased (manual vs automated: 48.4 (41.5-56.4)% vs 61.9 (48.5-72.3)%; p<0.01) and time SpO2 >95% decreased (41.9 (30.6-49.4)% vs 19.3 (11.5-24.5)%; p<0.001). The time SpO2<90% increased (8.6 (7.2-11.7)% vs 15.1 (14.0-21.1)%; p<0.0001), while SpO2<80% was similar (1.1 (0.4-1.7)% vs 0.9 (0.5-2.1)%; ns). CONCLUSIONS: During oxygen therapy, preterm infants spent more time within the SpO2 target range after implementation of automated oxygen control, with a significant reduction in hyperoxaemia, but not hypoxaemia.