The effect of vibrotactile stimulation on hypoxia-induced irregular breathing and apnea in preterm rabbits.

BACKGROUND: Manual tactile stimulation is used to counteract apnea in preterm infants, but it is unknown when this intervention should be applied. We compared an anticipatory to a reactive approach using vibrotactile stimulation to prevent hypoxia induced apneas. METHODS: Preterm rabbit kittens were prematurely delivered and randomized to either group. All kittens breathed spontaneously with a positive airway pressure of 8 cmH2O while they were imaged using phase contrast X-ray. Irregular breathing (IB) was induced using gradual hypoxia. The anticipatory group received stimulation at the onset of IB and the reactive group if IB transitioned into apnea. Breathing rate (BR), heart rate (HR) and functional residual capacity (FRC) were compared. RESULTS: Anticipatory stimulation significantly reduced apnea incidence and maximum inter-breath intervals and increased BR following IB, compared to reactive stimulation. Recovery in BR but not HR was more likely with anticipatory stimulation, although both BR and HR were significantly higher at 120 s after stimulation onset. FRC values and variability were not different. CONCLUSIONS: Anticipated vibrotactile stimulation is more effective in preventing apnea and enhancing breathing when compared to reactive stimulation in preterm rabbits. Stimulation timing is likely to be a key factor in reducing the incidence and duration of apnea. IMPACT: Anticipated vibrotactile stimulation can prevent apnea and stimulate breathing effort in preterm rabbits. Anticipated vibrotactile stimulation increases the likelihood of breathing rate recovery following hypoxia induced irregular breathing, when compared to reactive stimulation. Automated stimulation in combination with predictive algorithms may improve the treatment of apnea in preterm infants.

Technology in the delivery room supporting the neonatal healthcare provider's task.

Very preterm infants are a unique and highly vulnerable group of patients that have a narrow physiological margin within which interventions are safe and effective. The increased understanding of the foetal to neonatal transition marks the intricacy of the rapid and major physiological changes that take place, making delivery room stabilisation and resuscitation an increasingly complex and sophisticated activity for caregivers to perform. While modern, automated technologies are progressively implemented in the neonatal intensive care unit (NICU) to enhance the caregivers in providing the right care for these patients, the technology in the delivery room still lags far behind. Diligent translation of well-known and promising technological solutions from the NICU to the delivery room will allow for better support of the caregivers in performing their tasks. In this review we will discuss the current technology used for stabilisation of preterm infants in the delivery room and how this could be optimised in order to further improve care and outcomes of preterm infants in the near future.

Higher CPAP levels improve functional residual capacity at birth in preterm rabbits.

BACKGROUND: Preterm infants are commonly supported with 4-8 cm H2O continuous positive airway pressures (CPAP), although higher CPAP levels may improve functional residual capacity (FRC). METHODS: Preterm rabbits delivered at 29/32 days (~26-28 weeks human) gestation received 0, 5, 8, 12, 15 cm H2O of CPAP or variable CPAP of 15 to 5 or 15 to 8 cm H2O (decreasing ~2 cm H2O/min) for up to 10 min after birth. RESULTS: FRC was lower in the 0 (6.8 (1.0-11.2) mL/kg) and 5 (10.1 (1.1-16.8) mL/kg) compared to the 15 (18.8 (10.9-22.4) mL/kg) cm H2O groups (p = 0.003). Fewer kittens achieved FRC > 15 mL/kg in the 0 (20%), compared to 8 (36%), 12 (60%) and 15 (73%) cm H2O groups (p = 0.008). While breathing rates were not different (p = 0.096), apnoea tended to occur more often with CPAP < 8 cm H2O (p = 0.185). CPAP belly and lung bulging rates were similar whereas pneumothoraces were rare. Lowering CPAP from 15 to 5, but not 15 to 8 cm H2O, decreased FRC and breathing rates. CONCLUSION: In all, 15 cm H2O of CPAP improved lung aeration and reduced apnoea, but did not increase the risk of lung over-expansion, pneumothorax or CPAP belly immediately after birth. FRC and breathing rates were maintained when CPAP was decreased to 8 cm H2O. IMPACT: Although preterm infants are commonly supported with 4-8 cm H2O CPAP at birth, preclinical studies have shown that higher PEEP levels improve lung aeration. In this study, CPAP levels of 15 cm H2O improved lung aeration and reduced apnoea in preterm rabbit kittens immediately after birth. In all, 15 cm H2O CPAP did not increase the risk of lung over-expansion (indicated by bulging between the ribs), pneumothorax, or CPAP belly. These results can be used when designing future studies on CPAP strategies for preterm infants in the delivery room.

Feasibility and Effect of Physiological-Based CPAP in Preterm Infants at Birth.

Background: Preterm infants are commonly supported with 5-8 cmH2O CPAP. However, animal studies demonstrate that high initial CPAP levels (12-15 cmH2O) which are then reduced (termed physiological based (PB)-CPAP), improve lung aeration without adversely affecting cardiovascular function. We investigated the feasibility of PB-CPAP and the effect in preterm infants at birth. Methods: Preterm infants (24-30 weeks gestation) were randomized to PB-CPAP or 5-8 cmH2O CPAP for the first 10 min after birth. PB-CPAP consisted of 15 cmH2O CPAP that was decreased when infants were stabilized (heart rate ≥100 bpm, SpO2 ≥85%, FiO2 ≤ 0.4, spontaneous breathing) to 8 cmH2O with steps of ~2/3 cmH2O/min. Primary outcomes were feasibility and SpO2 in the first 5 min after birth. Secondary outcomes included physiological and breathing parameters and short-term neonatal outcomes. Planned enrollment was 42 infants. Results: The trial was stopped after enrolling 31 infants due to a low inclusion rate and recent changes in the local resuscitation guideline that conflict with the study protocol. Measurements were available for analysis in 28 infants (PB-CPAP n = 8, 5-8 cmH2O n = 20). Protocol deviations in the PB-CPAP group included one infant receiving 3 inflations with 15 cmH2O PEEP and two infants in which CPAP levels were decreased faster than described in the study protocol. In the 5-8 cmH2O CPAP group, three infants received 4, 10, and 12 cmH2O CPAP. During evaluations, caregivers indicated that the current PB-CPAP protocol was difficult to execute. The SpO2 in the first 5 min after birth was not different [61 (49-70) vs. 64 (47-74), p = 0.973]. However, infants receiving PB-CPAP achieved higher heart rates [121 (111-130) vs. 97 (82-119) bpm, p = 0.016] and duration of mask ventilation was shorter [0:42 (0:34-2:22) vs. 2:58 (1:36-6:03) min, p = 0.020]. Infants in the PB-CPAP group required 6:36 (5:49-11:03) min to stabilize, compared to 9:57 (6:58-15:06) min in the 5-8 cmH2O CPAP group (p = 0.256). There were no differences in short-term outcomes. Conclusion: Stabilization of preterm infants with PB-CPAP is feasible but tailoring CPAP appeared challenging. PB-CPAP did not lead to higher SpO2 but increased heart rate and shortened the duration of mask ventilation, which may reflect faster lung aeration.

The Effect of Initial Oxygen Exposure on Diaphragm Activity in Preterm Infants at Birth.

Background: The initial FiO2 that should be used for the stabilization of preterm infants in the delivery room (DR) is still a matter of debate as both hypoxia and hyperoxia should be prevented. A recent randomized controlled trial showed that preterm infants [gestational age (GA) < 30 weeks] stabilized with an initial high FiO2 (1.0) had a significantly higher breathing effort than infants stabilized with a low FiO2 (0.3). As the diaphragm is the main respiratory muscle in these infants, we aimed to describe the effects of the initial FiO2 on diaphragm activity. Methods: In a subgroup of infants from the original bi-center randomized controlled trial diaphragm activity was measured with transcutaneous electromyography of the diaphragm (dEMG), using three skin electrodes that were placed directly after birth. Diaphragm activity was compared in the first 5 min after birth. From the dEMG respiratory waveform several outcome measures were determined for comparison of the groups: average peak- and tonic inspiratory activity (dEMGpeak and dEMGton, respectively), inspiratory amplitude (dEMGamp), area under the curve (dEMGAUC) and the respiratory rate (RR). Results: Thirty-one infants were included in this subgroup, of which 29 could be analyzed [n = 15 (median GA 28.4 weeks) and n = 14 (median GA 27.9 weeks) for the 100 and 30% oxygen group, respectively]. Tonic diaphragm activity was significantly higher in the high FiO2-group (4.3 ± 2.1 µV vs. 2.9 ± 1.1 µV; p = 0.047). The other dEMG-parameters (dEMGpeak, dEMGamp, dEMGAUC) showed consistently higher values in the high FiO2 group, but did not reach statistical significance. Average RR showed similar values in both groups (34 ± 9 vs. 32 ± 10 breaths/min for the high and low oxygen group, respectively). Conclusion: Preterm infants stabilized with an initial high FiO2 showed significantly more tonic diaphragm activity and an overall trend toward a higher level of diaphragm activity than those stabilized with an initial low FiO2. These results confirm that a high initial FiO2 after birth stimulates breathing effort, which can be objectified with dEMG.

Comparing the effect of two different interfaces on breathing of preterm infants at birth: A matched-pairs analysis.

OBJECTIVE: Applying a face mask could provoke a trigeminocardiac reflex. We compared the effect of applying bi-nasal prongs with a face mask on breathing and heart rate of preterm infants at birth. METHODS: In a retrospective matched-pairs study of infants <32 weeks of gestation, the use of bi-nasal prongs for respiratory support at birth was compared to the use of a face mask. Infants who were initially breathing at birth and subsequently received respiratory support were matched for gestational age (±4 days), birth weight (±300 g), general anaesthesia and gender. Breathing, heart rate and other parameters were collected before and after interface application and in the first 5 min thereafter. RESULTS: In total, 130 infants were included (n = 65 bi-nasal prongs, n = 65 face mask) with a median (IQR) gestational age of 27+2 (25+3-28+4) vs 26+6 (25+3-28+5) weeks. The proportion of infants who stopped breathing after applying the interface was not different between the groups (bi-nasal prongs 43/65 (66%) vs face mask 46/65 (71%), p = 0.70). Positive pressure ventilation was given more often when bi-nasal prongs were used (55/65 (85%) vs 40/65 (62%), p < 0.001). Heart rate (101 (75-145) vs 110 (68-149) bpm, p = 0.496) and oxygen saturation (59% (48-87) vs 56% (35-84), p = 0.178) were similar in the first 5 min after an interface was applied in the infants who stopped breathing. CONCLUSION: Apnoea and bradycardia occurred often after applying either bi-nasal prongs or a face mask on the face for respiratory support in preterm infants at birth.

Improving the Quality of Provided Care: Lessons Learned From Auditing Neonatal Stabilization.

Video and physiological parameter recording of neonatal stabilization was implemented at the Neonatal Intensive Care Unit (NICU) of the Leiden University Medical Center. In order to improve documentation and the quality of care provided during neonatal transition, we implemented weekly plenary audits reviewing recordings of neonatal stabilization in 2014. In audits, provided care is reviewed, discussing, among others, mask technique, compliance to the prevailing local guideline, and clinical decision making and alternative treatment options. In this perspective, we argue that auditing neonatal stabilization is a valuable tool to improve patient safety and the quality of care provided during neonatal stabilization. We, therefore, report lessons learned and areas for improvement that could be identified and addressed during audits conducted at our NICU. Important areas for improvement were guideline compliance, documentation, the usage of medical devices, the conduct of delivery room studies, and clinical decision making. By reporting our experiences, we hope to encourage other NICUs to also implement regular audit meetings, fitting to their improvement needs.

Provider visual attention on a respiratory function monitor during neonatal resuscitation.

BACKGROUND: A respiratory function monitor (RFM) provides real-time positive pressure ventilation feedback. Whether providers use RFM during neonatal resuscitation is unknown. METHODS: Ancillary study to the MONITOR(NCT03256578) randomised controlled trial. Neonatal resuscitation leaders at two centres wore eye-tracking glasses, and visual attention (VA) patterns were compared between RFM-visible and RFM-masked groups. RESULTS: 14 resuscitations (6 RFM-visible, 8 RFM-masked) were analysed. The median total gaze duration on the RFM was significantly higher with a visible RFM (29% vs 1%, p<0.01), while median total gaze duration on other physical objects was significantly lower with a visible RFM (3% vs 8%, p=0.02). Median total gaze duration on the infant was lower with RFM visible, although not statistically significantly (29% vs 46%, p=0.05). CONCLUSION: Providers' VA patterns differed during neonatal resuscitation when the RFM was visible, emphasising the importance of studying the impact of additional delivery room technology on providers' behaviour.

Reflexes that impact spontaneous breathing of preterm infants at birth: a narrative review.

Some neural circuits within infants are not fully developed at birth, especially in preterm infants. Therefore, it is unclear whether reflexes that affect breathing may or may not be activated during the neonatal stabilisation at birth. Both sensory reflexes (eg, tactile stimulation) and non-invasive ventilation (NIV) can promote spontaneous breathing at birth, but the application of NIV can also compromise breathing by inducing facial reflexes that inhibit spontaneous breathing. Applying an interface could provoke the trigeminocardiac reflex (TCR) by stimulating the trigeminal nerve resulting in apnoea and a reduction in heart rate. Similarly, airflow within the nasopharynx can elicit the TCR and/or laryngeal chemoreflex (LCR), resulting in glottal closure and ineffective ventilation, whereas providing pressure via inflations could stimulate multiple receptors that affect breathing. Stimulating the fast adapting pulmonary receptors may activate Head's paradoxical reflex to stimulate spontaneous breathing. In contrast, stimulating the slow adapting pulmonary receptors or laryngeal receptors could induce the Hering-Breuer inflation reflex or LCR, respectively, and thereby inhibit spontaneous breathing. As clinicians are most often unaware that starting primary care might affect the breathing they intend to support, this narrative review summarises the currently available evidence on (vagally mediated) reflexes that might promote or inhibit spontaneous breathing at birth.

High-CPAP Does Not Impede Cardiovascular Changes at Birth in Preterm Sheep.

Objective: Continuous positive airway pressures (CPAP) used to assist preterm infants at birth are limited to 4-8 cmH2O due to concerns that high-CPAP may cause pulmonary overexpansion and adversely affect the cardiovascular system. We investigated the effects of high-CPAP on pulmonary (PBF) and cerebral (CBF) blood flows and jugular vein pressure (JVP) after birth in preterm lambs. Methods: Preterm lambs instrumented with flow probes and catheters were delivered at 133/146 days gestation. Lambs received low-CPAP (LCPAP: 5 cmH2O), high-CPAP (HCPAP: 15 cmH2O) or dynamic HCPAP (15 decreasing to 8 cmH2O at ~2 cmH2O/min) for up to 30 min after birth. Results: Mean PBF was lower in the LCPAP [median (Q1-Q3); 202 (48-277) mL/min, p = 0.002] compared to HCPAP [315 (221-365) mL/min] and dynamic HCPAP [327 (269-376) mL/min] lambs. CBF was similar in LCPAP [65 (37-78) mL/min], HCPAP [73 (41-106) mL/min], and dynamic HCPAP [66 (52-81) mL/min, p = 0.174] lambs. JVP was similar at CPAPs of 5 [8.0 (5.1-12.4) mmHg], 8 [9.4 (5.3-13.4) mmHg], and 15 cmH2O [8.6 (6.9-10.5) mmHg, p = 0.909]. Heart rate was lower in the LCPAP [134 (101-174) bpm; p = 0.028] compared to the HCPAP [173 (139-205)] and dynamic HCPAP [188 (161-207) bpm] groups. Ventilation or additional caffeine was required in 5/6 LCPAP, 1/6 HCPAP, and 5/7 dynamic HCPAP lambs (p = 0.082), whereas 3/6 LCPAP, but no HCPAP lambs required intubation (p = 0.041), and 1/6 LCPAP, but no HCPAP lambs developed a pneumothorax (p = 0.632). Conclusion: High-CPAP did not impede the increase in PBF at birth and supported preterm lambs without affecting CBF and JVP.

Paediatric exhaled CO2 detector causes leaks.

OBJECTIVE: To assess leakage caused by the Pedi-Cap. METHODS: Bench test I: Pedi-Caps were connected between the Neopuff and a test lung and placed underwater to detect the leak. Bench test II: the disposable Avea VarFlex Flow Transducer measured the leak. Retrospective analysis: recordings of intubations in the delivery room were analysed. RESULTS: The (rippled) male end of the Pedi-Cap is the origin of the leak. In bench test I, 32% of the Pedi-Caps caused inevitable extensive leaks and 34% caused leaks that diminished after sealing the end. In bench test II (n=44) and the retrospective analysis (n=17), the flow transducer measured 22% (18-60) and 39% (8-82) leakage, respectively. Leakage decreased after removal of the Pedi-Cap (before vs after; 17% (7-75) vs 4% (2-10), p=0.004). CONCLUSION: The Pedi-Cap causes the leak which can compromise respiratory support. We recommend to remove the Pedi-Cap directly after change of colour and to be cautious when using the device as evaluation tool.

Increasing Respiratory Effort With 100% Oxygen During Resuscitation of Preterm Rabbits at Birth.

Background: Spontaneous breathing is essential for successful non-invasive respiratory support delivered by a facemask at birth. As hypoxia is a potent inhibitor of spontaneous breathing, initiating respiratory support with a high fraction of inspired O2 may reduce the risk of hypoxia and increase respiratory effort at birth. Methods: Preterm rabbit kittens (29 days gestation, term ~32 days) were delivered and randomized to receive continuous positive airway pressure with either 21% (n = 12) or 100% O2 (n = 8) via a facemask. If apnea occurred, intermittent positive pressure ventilation (iPPV) was applied with either 21% or 100% O2 in kittens who started in 21% O2, and remained at 100% O2 for kittens who started the experiment in 100% O2. Respiratory rate (breaths per minute, bpm) and variability in inter-breath interval (%) were measured from esophageal pressure recordings and functional residual capacity (FRC) was measured from synchrotron phase-contrast X-ray images. Results: Initially, kittens receiving 21% O2 had a significantly lower respiratory rate and higher variability in inter-breath interval, indicating a less stable breathing pattern than kittens starting in 100% O2 [median (IQR) respiratory rate: 16 (4-28) vs. 38 (29-46) bpm, p = 0.001; variability in inter-breath interval: 33.3% (17.2-50.1%) vs. 27.5% (18.6-36.3%), p = 0.009]. Apnea that required iPPV, was more frequently observed in kittens in whom resuscitation was started with 21% compared to 100% O2 (11/12 vs. 1/8, p = 0.001). After recovering from apnea, respiratory rate was significantly lower and variability in inter-breath interval was significantly higher in kittens who received iPPV with 21% compared to 100% O2. FRC was not different between study groups at both timepoints. Conclusion: Initiating resuscitation with 100% O2 resulted in increased respiratory activity and stability, thereby reducing the risk of apnea and need for iPPV after birth. Further studies in human preterm infants are mandatory to confirm the benefit of this approach in terms of oxygenation. In addition, the ability to avoid hyperoxia after initiation of resuscitation with 100% oxygen, using a titration protocol based on oxygen saturation, needs to be clarified.

The effect of a face mask for respiratory support on breathing in preterm infants at birth.

OBJECTIVE: Applying a mask on the face for respiratory support could induce a trigeminocardiac reflex leading to apnoea and bradycardia. We have examined the effect of applying a face mask on breathing and heart rate in preterm infants at birth. METHODS: Resuscitation videos of infants ≤ 32 weeks gestation recorded from 2010 until 2018 at the Leiden University Medical Centre and the General University Hospital in Prague were reviewed. All infants received respiratory support via face mask. Breathing and heart rate were noted before and after application of the face mask and over the first 5 min. RESULTS: Recordings of 429 infants were included (median (IQR) gestational age of 28+6 (27+1-30+4) weeks). In 368/429 (86%) infants breathing was observed before application of the face mask and 197/368 (54%) of these infants stopped breathing following application of the face mask. Apnoea occurred at a median of 5 (3-17) seconds after application of the face mask with a duration of 28 (22-34) seconds of the first minute. In a logistic regression model, the occurrence of apnoea after face mask application was inversely associated with gestational age (OR = 1.424 (1.281-1.583), p < 0.001). Infants who stopped breathing had a significantly lower heart rate 82 (66-123) vs 134 (97-151) bpm, p < 0.001) and oxygen saturation (49% (33-59) vs 66% (50-82), p < 0.001) over the first minute after face mask application, compared to infants who continued breathing. CONCLUSION: Applying a face mask for respiratory support affects breathing in a large proportion (54%) of preterm infants and this effect is gestational age dependent.

Comparison of Two Respiratory Support Strategies for Stabilization of Very Preterm Infants at Birth: A Matched-Pairs Analysis.

Objective: Respiratory support for stabilizing very preterm infants at birth varies between centers. We retrospectively compared two strategies that involved either increasing continuous positive airway pressures (CPAP), or increasing oxygen supplementation. Methods: Matched-pairs of infants (<28 weeks of gestation) were born either at the Leiden University Medical Center [low-pressure: CPAP 5-8 cmH2O and/or positive pressure ventilation (PPV) and fraction of inspired oxygen (FiO2) 0.3-1.0; n = 27], or at the University Hospital of Cologne (high-pressure: CPAP 12-35 cmH2O, no PPV and FiO2 0.3-0.4; n = 27). Respiratory support was initiated non-invasively via facemask at both units. Infants (n = 54) were matched between centers for gestational age and birth weight, to compare physiological and short-term clinical outcomes. Results: In the low-pressure group, 20/27 (74%) infants received 1-2 sustained inflations (20, 25 cm H2O) and 22/27 (81%) received PPV (1:19-3:01 min) using pressures of 25-27 cm H2O. Within 3 min of birth [median (IQR)], mean airway pressures [12 (6-15) vs. 19 (16-23) cmH2O, p < 0.001] and FiO2 [0.30 (0.28-0.31) vs. 0.22 (0.21-0.30), p < 0.001] were different in low- vs. high-pressure groups, respectively. SpO2 and heart rates were similar. After 3 min, higher FiO2 levels [0.62 (0.35-0.98) vs. 0.28 (0.22-0.38), p = 0.005] produced higher SpO2 levels [77 (50-92) vs. 53 (42-69)%, p < 0.001] in the low-pressure group, but SpO2/FiO2 and heart rates were similar. While intubation rates during admission were significantly different (70 vs. 30%, p = 0.013), pneumothorax rates (4 vs. 19%, p = 0.125) and the occurrence of spontaneous intestinal perforations (0 vs. 15%, p = 0.125) were similar between groups. Conclusion: Infants (<28 weeks) can be supported non-invasively at birth with either higher or lower pressures and while higher-pressure support may require less oxygen, it does not eliminate the need for oxygen supplementation. Future studies need to examine the effect of high pressures and pressure titration in the delivery room.

Supporting breathing of preterm infants at birth: a narrative review.

Most very preterm infants have difficulty aerating their lungs and require respiratory support at birth. Currently in clinical practice, non-invasive ventilation in the form of continuous positive airway pressure (CPAP) and positive pressure ventilation (PPV) is applied via facemask. As most very preterm infants breathe weakly and unnoticed at birth, PPV is often administered. PPV is, however, frequently ineffective due to pressure settings, mask leak and airway obstruction. Meanwhile, high positive inspiratory pressures and spontaneous breathing coinciding with inflations can generate high tidal volumes. Evidence from preclinical studies demonstrates that high tidal volumes can be injurious to the lungs and brains of premature newborns. To reduce the need for PPV in the delivery room, it should be considered to optimise spontaneous breathing with CPAP. CPAP is recommended in guidelines and commonly used in the delivery room after a period of PPV, but little data is available on the ideal CPAP strategy and CPAP delivering devices and interfaces used in the delivery room. This narrative review summarises the currently available evidence for why PPV can be inadequate at birth and what is known about different CPAP strategies, devices and interfaces used the delivery room.

The Effect of Initial High vs. Low FiO2 on Breathing Effort in Preterm Infants at Birth: A Randomized Controlled Trial.

Background: Infants are currently stabilized at birth with initial low FiO2 which increases the risk of hypoxia and suppression of breathing in the first minutes after birth. We hypothesized that initiating stabilization at birth with a high O2 concentration, followed by titration, would improve breathing effort when compared to a low O2 concentration, followed by titration. Methods: In a bi-center randomized controlled trial, infants <30 weeks gestation were stabilized at birth with an initial O2 concentration of 30 or 100%, followed by oxygen titration. Primary outcome was minute volume of spontaneous breathing. We also assessed tidal volumes, mean inspiratory flow rate (MIFR) and respiratory rate with a respiratory function monitor in the first 5 min after birth, and evaluated the duration of mask ventilation in the first 10 min after birth. Pulse oximetry was used to measure heart rate and SpO2 values in the first 10 min. Hypoxemia was defined as SpO2 < 25th percentile and hyperoxemia as SpO2 >95%. 8-iso-prostaglandin F2α (8iPGF2α) was measured to assess oxidative stress in cord blood and 1 and 24 h after birth. Results: Fifty-two infants were randomized and recordings were obtained in 44 infants (100% O2-group: n = 20, 30% O2-group: n = 24). Minute volumes were significantly higher in the 100% O2-group (146.34 ± 112.68 mL/kg/min) compared to the 30% O2-group (74.43 ± 52.19 mL/kg/min), p = 0.014. Tidal volumes and MIFR were significantly higher in the 100% O2-group, while the duration of mask ventilation given was significantly shorter. Oxygenation in the first 5 min after birth was significantly higher in infants in the 100% O2-group [85 (64-93)%] compared to the 30% O2-group [58 (46-67)%], p < 0.001. The duration of hypoxemia was significantly shorter in the 100% O2-group, while the duration of hyperoxemia was not different between groups. There was no difference in oxidative stress marker 8iPGF2α between the groups. Conclusion: Initiating stabilization of preterm infants at birth with 100% O2 led to higher breathing effort, improved oxygenation, and a shorter duration of mask ventilation as compared to 30% O2, without increasing the risk for hyperoxia or oxidative stress. Clinical Trial Registration: This study was registered in www.trialregister.nl, with registration number NTR6878.

Repetitive versus standard tactile stimulation of preterm infants at birth - A randomized controlled trial.

AIM: To evaluate the direct effect of repetitive tactile stimulation on breathing effort of preterm infants at birth. METHODS: This randomized controlled trial compared the effect of repetitive stimulation on respiratory effort during the first 4 min after birth with standard stimulation based on clinical indication in preterm infants with a gestational age of 27-32 weeks. All details of the stimulation performed were noted. The main study parameter measured was respiratory minute volume, other study parameters assessed measures of respiratory effort; tidal volumes, rate of rise to maximum tidal volumes, percentage of recruitment breaths, and oxygenation of the infant. RESULTS: There was no significant difference in respiratory minute volume in the repetitive stimulation group when compared to the standard group. Oxygen saturation was significantly higher (87.6 ±â€¯3.3% vs 81.7 ±â€¯8.7%, p = .01) while the amount of FiO2 given during transport to the NICU was lower (28.2 (22.8-35.0)% vs 33.6 (29.4-44.1)%, p = .04). There was no significant difference in administration of positive pressure ventilation (52% vs 78%, p = .13), or the duration of ventilation (median (IQR) time 8 (0-118)s vs 35 (13-131)s, p = .23). Caregivers decided less often to administer caffeine in the delivery room to stimulate breathing in the repetitive stimulation group (10% vs 39%, p = .036). CONCLUSION: Although the increase in respiratory effort during repetitive stimulation did not reach significance, oxygenation significantly improved with a lower level of FiO2 at transport to the NICU. Repetitive tactile stimulation could be of added value to improve breathing effort at birth.

Tactile Stimulation to Stimulate Spontaneous Breathing during Stabilization of Preterm Infants at Birth: A Retrospective Analysis.

BACKGROUND AND AIMS: Tactile maneuvers to stimulate breathing in preterm infants are recommended during the initial assessment at birth, but it is not known how often and how this is applied. We evaluated the occurrence and patterns of tactile stimulation during stabilization of preterm infants at birth. METHODS: Recordings of physiological parameters and videos of infants <32 weeks gestational age were retrospectively analyzed. Details of tactile stimulation during the first 7 min after birth (timing, duration, type, and indication) were noted. RESULTS: Stimulation was performed in 164/245 (67%) infants. The median (IQR) GA was 28 6/7 (27 2/7-30 1/7) weeks, birth weight 1,153 (880-1,385) g, Apgar score at 5 min was 8 (7-9), 140/245 (57%) infants were born after cesarean section, and 134/245 (55%) were male. There were no significant differences between the stimulated and the non-stimulated infants with regard to basic characteristics. In the stimulated infants, the first episode of stimulation was given at a median (IQR) of 114 (73-182) s after birth. Stimulation was repeated 3 (1-5) times, with a median (IQR) duration of 8 (4-16) s and a total duration of 32 (15-64) s. Modes of stimulation were: rubbing (68%) or flicking (2%) the soles of the feet, rubbing the back (12%), a combination (9%), or other (8%). In 67% of the stimulation episodes, a clear indication was noted (25% bradycardia, 57% apnea, 48% hypoxemia, 43% combination) and an effect was observed in 18% of these indicated stimulation episodes. A total effect of all stimulation episodes per infant remains unclear, but infants who did not receive stimulation were more often intubated in the delivery room (14/79 (18%) vs 12/164 (7%), p < 0.05). CONCLUSION: There was a large variation in the use of tactile stimulation in preterm infants during stabilization at birth. In most cases, there was an indication for stimulation, but only in a small proportion an effect could be observed.