Airway management may influence postoperative ventilation need in preterm infants after laser eye treatment.

BACKGROUND: Retinopathy of prematurity is treated with laser photocoagulation under general anaesthesia with intubation using endotracheal tube (ETT), which carries a risk for postoperative mechanical ventilation (MV). Laryngeal mask airway (LMA) may provide a safe alternative. We assessed the need for postoperative MV in preterm infants who received LMA versus ETT. METHODS: In this single-centre, retrospective cohort study, preterm infants who underwent laser photocoagulation between 2014-2021 were enroled. For airway management, patients received either LMA (n = 224) or ETT (n = 47). The outcome was the rate of postoperative MV. RESULTS: Patients' age were 37 [35;39] weeks of postmenstrual age, median bodyweight of Group LMA was higher than Group ETT's (2110 [1800;2780] g versus 1350 [1230;1610] g, respectively, p < 0.0001). After laser photocoagulation, 8% of Group LMA and 74% of Group ETT left the operating theatre requiring MV. Multiple logistic regression revealed that the use of LMA and every 100 g increase in bodyweight significantly decreased the odds of mechanical ventilation (OR 0.21 [95% CI 0.07-0.60], and 0.73 [95% CI 0.63-0.84], respectively). Propensity score matching confirmed that LMA decreased the odds of postoperative MV (OR 0.30 [95% CI 0.11-0.70]). CONCLUSION: The use of LMA is associated with a reduced need for postoperative MV. IMPACT: Using laryngeal mask airway instead of endotracheal tube for airway management in preterm infants undergoing general anaesthesia for laser photocoagulation for treating retinopathy of prematurity could significantly decrease the postoperative need for mechanical ventilation. According to our current understanding, this has been the largest study investigating the effect of laryngeal mask airway during general anaesthesia in preterm infants. Our study suggests that the use of laryngeal mask airway is a viable alternative to intubation in the vulnerable population of preterm infants in need of laser treatment.

Low inflating pressures during neonatal tidal volume targeted ventilation: occurrence and significance.

OBJECTIVES: We investigated the inflating pressures (Pinfl, the difference between peak inspiratory pressure and positive end-expiratory pressure) in infants receiving volume targeted ventilation. METHODS: Data were collected and analysed from 195 infants. Median Pinfl was determined before each blood gas (n = 3425). Ventilator parameters and blood gases were compared between periods when Pinfl was <5 mbar and periods when it was higher. RESULTS: 1-hour periods when median Pinfl was <5 mbar occurred in 30% of the babies and were associated with similar tidal volumes and minutes ventilation as periods with higher Pinfl. Babies triggered more ventilator inflations, had more spontaneous breaths and lower oxygen requirement when Pinfl was low. There was no difference in blood gases when Pinfl was <5 mbar or when it was higher. CONCLUSIONS: Episodes of low inflating pressure occur frequently in babies receiving volume targeted ventilation, but they do not lead to changes in blood gases.

Time series analysis of non-invasive hemodynamic monitoring data in neonates with hypoxic-ischemic encephalopathy.

Background and aims: Hemodynamic instability is common in neonates with hypoxic-ischemic encephalopathy (HIE) undergoing therapeutic hypothermia (TH). Rewarming is a critical period and non-invasive circulatory monitoring may help guide cardiovascular supportive therapy. The aim of the study was to provide a comprehensive analysis of cardiac function parameters during TH and its relation to neurodevelopmental outcome. Methods: In a prospective, observational study, 26 neonates with moderate-severe HIE were enrolled, born between 2016 and 2019. A hemodynamic monitor based on electrical velocimetry (ICON, Osypka Medical GmbH, Berlin, Germany) was used. Heart rate (HR), stroke volume (SV), cardiac output (CO) data were recorded continuously throughout TH and rewarming. Neurological outcome was assessed at 2 years of age using the Bayley Scales of Infant Development II. edition. Favorable outcome was defined as >70 points on both the psychomotor and mental scales. Time-series analysis was used and features of cardiac function were described to perform logistic regression modeling for outcome prediction. Results: Fourteen (54%) patients had favorable and 12 (46%) had adverse outcome. Data collection started from median [IQR] of 11.8 [7.0; 24.3] hours (h) of life and lasted until 84.0. [81.8; 87.0] h. During TH, the mean HR of the favorable outcome group was significantly lower than that of the adverse outcome group (86 ± 13/min vs. 104 ± 18/min, p = 0.01). During rewarming HR increased similarly in both groups. SV was unaffected by rewarming, and showed a slowly increasing trend. SV of the favorable outcome group was significantly higher compared to the adverse outcome group (1.55 ± 0.23 ml/kg vs. 1.29 ± 0.30 ml/kg, p = 0.035). In line with this, CO was similar in both groups (136 ± 27 ml/kg/min vs. 134 ± 36 ml/kg/min), and a significant 25% increase in CO was observed during rewarming. Based on multiple regression modeling, HR during TH was independently associated with neurological outcome (p = 0.023). Conclusion: Based on continuous hemodynamic monitoring, patients with adverse outcome have lower SV and higher HR to achieve similar CO to patients with favorable outcome during TH. HR during hypothermia is independently associated with the neurodevelopmental outcome.