Comparison of two different oxygen saturation target ranges for automated oxygen control in preterm infants: a randomised cross-over trial.

OBJECTIVE: To compare the effect of peripheral oxygen saturation (SpO2) target range (TR) (either 91%-95% and 92%-96%) on the frequency and duration of hypoxic and hyperoxic episodes while on automated oxygen control using the OxyGenie controller. DESIGN: Randomised cross-over study. SETTING: Tertiary-level neonatal unit in the Netherlands. PATIENTS: Infants (n=27) with a median (IQR) gestational age of 27+0 (25+5-27+3) weeks and postnatal age of 16 (10-22) days, receiving invasive or non-invasive respiratory support. INTERVENTIONS: In both groups supplemental oxygen was titrated to a TR of 91%-95% (TRlow) or 92%-96% (TRhigh) by the OxyGenie controller (SLE6000 ventilator) for 24 hours each, in random sequence. After a switch in TR, a 1-hour washout period was applied to prevent carry-over bias. MAIN OUTCOME MEASURES: Frequency and duration of hypoxic (SpO2<80% for ≥1 s) and hyperoxic episodes (SpO2>98% for ≥1 s). RESULTS: Hypoxic episodes were less frequent when the higher range was targeted (TRhigh vs TRlow: 2.5 (0.7-6.2)/hour vs 2.4 (0.9-10.2)/hour, p=0.02), but hyperoxic episodes were more frequent (5.3 (1.8-12.3)/hour vs 2.9 (1.0-7.1)/hour, p<0.001). The duration of the out-of-range episodes was not significantly different (hypoxia: 4.7 (2.8-7.1) s vs 4.4 (3.7-6.5) s, p=0.67; hyperoxia: 4.3 (3.3-4.9) s vs 3.9 (2.8-5.5) s, p=0.89). CONCLUSION: Targeting a higher SpO2 TR with the OxyGenie controller reduced hypoxic episodes but increased hyperoxic episodes. This study highlights the feasibility of using an automated oxygen titration device to explore the effects of subtle TR adjustments on clinical outcomes in neonatal care. TRIAL REGISTRATION NUMBER: NL9662.

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.

Minimising alarm pressure on a single room NICU through automated withdrawal of resolved alarms.

AIM: In 2017, the Leiden University Medical Centre implemented a secondary alarm system using handheld devices to ensure accurate patient monitoring on the single room NICU. Initially, alarms remained active on the handheld devices until one of the caregivers in the alarm chain accepted the alarm. In 2020, a bidirectional communication protocol (BCP) was implemented, enabling automated withdrawal of resolved alarms. The aim of this study was to evaluate the effect of this implementation on the alarm duration and pressure. METHODS: Data of all alarms of the secondary alarm chain in the 90 days before and after the implementation were analysed and compared between both periods. RESULTS: Following the implementation of the BCP, 60% of the alarms were withdrawn before the designated nurse responded. Despite a significant higher total number of alarms, the median alarm duration decreased from 9 (7-14) to 6 (4-10) s, the acceptance rate of the designated nurse increased from 93% to 95% and the median time of alarm sounding per phone per hour significantly decreased from 71 (51-101) to 51 (35-69) s following implementation of the BCP. CONCLUSION: This study showed that automated withdrawal of resolved alarms significantly reduces alarm duration and pressure on a NICU.

The effect of imposed resistance in neonatal resuscitators on pressure stability and peak flows: a bench test.

BACKGROUND: The importance of neonatal resuscitator resistance is currently unknown. In this study we investigated peak flows and pressure stability resulting from differences in imposed resistance during positive pressure ventilation(PPV) and simulated spontaneous breathing (SSB) between the r-PAP, low-resistance resuscitator, and Neopuff™, high-resistance resuscitator. METHODS: In a bench test, 20 inflations during PPV and 20 breaths during SSB were analysed on breath-by-breath basis to determine peak flow and pressure stability using the Neopuff™ with bias gas flow of 8, 12 or 15 L/min and the r-PAP with total gas flow of 15 L/min. RESULTS: Imposed resistance of the Neopuff™ was significantly reduced when the bias gas flow was increased from 8 to 15 L/min, which resulted in higher peak flows during PPV and SSB. Peak flows in the r-PAP were, however, significantly higher and fluctuations in CPAP during SSB were significantly smaller in the r-PAP compared to the Neopuff™ for all bias gas flow levels. During PPV, a pressure overshoot of 3.2 cmH2O was observed in the r-PAP. CONCLUSIONS: The r-PAP seemed to have a lower resistance than the Neopuff™ even when bias gas flows were increased. This resulted in more stable CPAP pressures with higher peak flows when using the r-PAP. IMPACT: The traditional T-piece system (Neopuff™) has a higher imposed resistance compared to a new neonatal resuscitator (r-PAP). This study shows that reducing imposed resistance leads to smaller CPAP fluctuations and higher inspiratory and expiratory peak flows. High peak flows might negatively affect lung function and/or cause lung injury in preterm infants at birth. This study will form the rationale for further studies investigating these effects. A possible compromise might be to use the traditional T-piece system with a higher bias gas flow (12 L/min), thereby reducing the imposed resistance and generating more stable PEEP/CPAP pressures, while limiting potentially harmful peak flows.

Effect of initial and subsequent mask applications on breathing and heart rate in preterm infants at birth.

OBJECTIVE: Application of a face mask may provoke the trigeminocardiac reflex, leading to apnoea and bradycardia. This study investigates whether re-application of a face mask in preterm infants at birth alters the risk of apnoea compared with the initial application, and identify factors that influence this risk. METHODS: Resuscitation videos and respiratory function monitor data collected from preterm infants <30 weeks gestation between 2018 and 2020 were reviewed. Breathing and heart rate before and after the initial and subsequent mask applications were analysed. RESULTS: In total, 111 infants were included with 404 mask applications (102 initial and 302 subsequent mask applications). In 254/404 (63%) applications, infants were breathing prior to mask application, followed by apnoea after 67/254 (26%) mask applications. Apnoea and bradycardia occurred significantly more often after the initial mask application compared with subsequent applications (apnoea initial: 32/67 (48%) and subsequent: 44/187 (24%), p<0.001; bradycardia initial: 61% and subsequent 21%, p<0.001). Apnoea was followed by bradycardia in 73% and 71% of the initial and subsequent mask applications, respectively (p=0.607).In a logistic regression model, a lower breathing rate (OR 0.908 (95% CI 0.847 to 0.974), p=0.007) and heart rate (OR 0.935 (95% CI 0.901 to 0.970), p<0.001) prior to mask application were associated with an increased likelihood of becoming apnoeic following subsequent mask applications. CONCLUSION: In preterm infants at birth, apnoea and bradycardia occurs more often after an initial mask application than subsequent applications, with lower heart and breathing rates increasing the risk of apnoea in subsequent applications.

Developing a design-based concept to improve hand hygiene in the neonatal intensive care unit.

BACKGROUND: Hand hygiene (HH) is the most critical measure in the prevention of nosocomial infections in the neonatal intensive care unit (NICU). Improving and sustaining adequate HH compliance rates, however, remains a significant challenge. Using a behavioral change framework and nudge theory, we developed a design-based concept aimed at facilitating and stimulating HH behavior. METHODS: Concept development was initiated by selecting a theoretical framework after which contextual field studies aimed at discovering causes for poor compliance were conducted. Potential solutions were brainstormed upon during focus group sessions. Low-fidelity prototypes were tested regarding feasibility, usability, and acceptability. A final concept was crafted drawing from findings from each design phase. RESULTS: Complying with recommended HH guidelines is unrealistic and infeasible due to frequent competing (clinical) priorities requiring HH. The concept "Island-based nursing," where a patient room is divided into two geographical areas, namely, the island and general zone, was created. HH must be performed upon entering and exiting the island zone, and after exposure to any surface within the general zone. Reminding of HH is prompted by illuminated demarcation of the island zone, serving as the concept's nudge. CONCLUSIONS: Island zone demarcation facilitates and economizes HH indications in an innovative and intuitive manner. IMPACT: Although hand hygiene (HH) is the single most important element in the prevention of nosocomial infections in neonates, improving and sustaining adequate HH compliance rates remains a significant challenge. Complying with recommended HH guidelines was found to be unrealistic and infeasible due to the significant amount of time required for HH in a setting with a high workload and many competing (clinical) priorities. The concept of "Island-based nursing," under which the primary HH indication is upon entering and exiting the island zone, facilitates and economizes HH indications in an innovative and user-friendly manner.

Clinical outcomes of preterm infants while using automated controllers during standard care: comparison of cohorts with different automated titration strategies.

OBJECTIVE: To compare short-term clinical outcome after using two different automated oxygen controllers (OxyGenie and CLiO2). DESIGN: Propensity score-matched retrospective observational study. SETTING: Tertiary-level neonatal unit in the Netherlands. PATIENTS: Preterm infants (OxyGenie n=121, CLiO2 n=121) born between 24+0-29+6 weeks of gestation. Median (IQR) gestational age in the OxyGenie cohort was 28+3 (26+3.5-29+0) vs 27+5 (26+5-28+3) in the CLiO2 cohort, respectively 42% and 46% of infants were male and mean (SD) birth weight was 1034 (266) g vs 1022 (242) g. INTERVENTIONS: Inspired oxygen was titrated by OxyGenie (SLE6000) or CLiO2 (AVEA) during respiratory support. MAIN OUTCOME MEASURES: Mortality, retinopathy of prematurity (ROP), bronchopulmonary dysplasia and necrotising enterocolitis. RESULTS: Fewer infants in the OxyGenie group received laser coagulation for ROP (1 infant vs 10; risk ratio 0.1 (95% CI 0.0 to 0.7); p=0.008), and infants stayed shorter in the neonatal intensive care unit (NICU) (28 (95% CI 15 to 42) vs 40 (95% CI 25 to 61) days; median difference 13.5 days (95% CI 8.5 to 19.5); p<0.001). Infants in the OxyGenie group had fewer days on continuous positive airway pressure (8.4 (95% CI 4.8 to 19.8) days vs 16.7 (95% CI 6.3 to 31.1); p<0.001) and a significantly shorter days on invasive ventilation (0 (95% CI 0 to 4.2) days vs 2.1 (95% CI 0 to 8.4); p=0.012). There were no statistically significant differences in all other morbidities. CONCLUSIONS: In this propensity score-matched retrospective study, the OxyGenie epoch was associated with less morbidity when compared with the CLiO2 epoch. There were significantly fewer infants that received treatment for ROP, received less intensive respiratory support and, although there were more supplemental oxygen days, the duration of stay in the NICU was shorter. A larger study will have to replicate these findings.

The Effect of a Higher Bias Gas Flow on Imposed T-Piece Resistance and Breathing in Preterm Infants at Birth.

Objective: The resistance created by the PEEP-valve of a T-piece resuscitator is bias gas flow dependent and might affect breathing in preterm infants. In this study we investigated the effect of a higher bias gas flow on the imposed inspiratory and expiratory T-piece resistance and expiratory breaking manoeuvres (EBM) in preterm infants during spontaneous breathing on CPAP at birth. Methods: In a retrospective pre-post implementation study of preterm infants <32 weeks gestation, who were stabilised with a T-piece resuscitator, a bias gas flow of 12 L/min was compared to 8 L/min. All spontaneous breaths on CPAP within the first 10 min of starting respiratory support were analysed on a breath-by-breath basis to determine the breathing pattern of each breath and to calculate the imposed inspiratory and expiratory T-piece resistance (Ri, Re), flow rates and tidal volume. Results: In total, 54 infants were included (bias gas flow 12 L/min: n = 27, 8 L/min: n = 27) with a median GA of 29+6 (28+4-30+3) and 28+5 (25+6-30+3), respectively (p = 0.182). Ri and Re were significantly lower in the 12 L/min compared to 8 L/min bias flow group [Ri: 29.6 (26.1-33.6) vs. 46.4 (43.0-54.1) cm H2O/L/s, p < 0.001; Re: 32.0 (30.0-35.1) vs. 48.0 (46.3-53.9) cm H2O/L/s, p < 0.001], while the incidence of EBM [77% (53-88) vs. 77% (58-90), p = 0.586] was similar. Conclusion: During stabilisation of preterm infants at birth with a T-piece resuscitator, the use of a higher bias gas flow reduced both the imposed inspiratory and expiratory T-piece resistance for the infant, but this did not influence the incidence of EBMs.

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.

Comparison of two devices for automated oxygen control in preterm infants: a randomised crossover trial.

OBJECTIVE: To compare the effect of two different automated oxygen control devices on target range (TR) time and occurrence of hypoxaemic and hyperoxaemic episodes. DESIGN: Randomised cross-over study. SETTING: Tertiary level neonatal unit in the Netherlands. PATIENTS: Preterm infants (n=15) born between 24+0 and 29+6 days of gestation, receiving invasive or non-invasive respiratory support with oxygen saturation (SpO2) TR of 91%-95%. Median gestational age 26 weeks and 4 days (IQR 25 weeks 3 days-27 weeks 6 days) and postnatal age 19 (IQR 17-24) days. INTERVENTIONS: Inspired oxygen concentration was titrated by the OxyGenie controller (SLE6000 ventilator) and the CLiO2 controller (AVEA ventilator) for 24 hours each, in a random sequence, with the respiratory support mode kept constant. MAIN OUTCOME MEASURES: Time spent within set SpO2 TR (91%-95% with supplemental oxygen and 91%-100% without supplemental oxygen). RESULTS: Time spent within the SpO2 TR was higher during OxyGenie control (80.2 (72.6-82.4)% vs 68.5 (56.7-79.3)%, p<0.005). Less time was spent above TR while in supplemental oxygen (6.3 (5.1-9.9)% vs 15.9 (11.5-30.7)%, p<0.005) but more time spent below TR during OxyGenie control (14.7 (11.8%-17.2%) vs 9.3 (8.2-12.6)%, p<0.05). There was no significant difference in time with SpO2 <80% (0.5 (0.1-1.0)% vs 0.2 (0.1-0.4)%, p=0.061). Long-lasting SpO2 deviations occurred less frequently during OxyGenie control. CONCLUSIONS: The OxyGenie control algorithm was more effective in keeping the oxygen saturation within TR and preventing hyperoxaemia and equally effective in preventing hypoxaemia (SpO2 <80%), although at the cost of a small increase in mild hypoxaemia. TRIAL REGISTRY NUMBER: NCT03877198.

Sensory stimulation for apnoea mitigation in preterm infants.

Apnoea, a pause in respiration, is ubiquitous in preterm infants and are often associated with physiological instability, which may lead to longer-term adverse neurodevelopmental consequences. Despite current therapies aimed at reducing the apnoea burden, preterm infants continue to exhibit apnoeic events throughout their hospital admission. Bedside staff are frequently required to manually intervene with different forms of stimuli, with the aim of re-establishing respiratory cadence and minimizing the physiological impact of each apnoeic event. Such a reactive approach makes apnoea and its associated adverse consequences inevitable and places a heavy reliance on human intervention. Different approaches to improving apnoea management in preterm infants have been investigated, including the use of various sensory stimuli. Despite studies reporting sensory stimuli of various forms to have potential in reducing apnoea frequency, non-invasive intermittent positive pressure ventilation is the only automated stimulus currently used in the clinical setting for infants with persistent apnoeic events. We find that the development of automated closed-looped sensory stimulation systems for apnoea mitigation in preterm infants receiving non-invasive respiratory support is warranted, including the possibility of stimulation being applied preventatively, and in a multi-modal form. IMPACT: This review examines the effects of various forms of sensory stimulation on apnoea mitigation in preterm infants, namely localized tactile, generalized kinesthetic, airway pressure, auditory, and olfactory stimulations. Amongst the 31 studies reviewed, each form of sensory stimulation showed some positive effects, although the findings were not definitive and comparative studies were lacking. We find that the development of automated closed-loop sensory stimulation systems for apnoea mitigation is warranted, including the possibility of stimulation being applied preventatively, and in a multi-modal form.

Increased end-expiratory pressures improve lung function in near-term newborn rabbits with elevated airway liquid volume at birth.

Approximately 53% of near-term newborns admitted to intensive care experience respiratory distress. These newborns are commonly delivered by cesarean section and have elevated airway liquid volumes at birth, which can cause respiratory morbidity. We investigated the effect of providing respiratory support with a positive end-expiratory pressure (PEEP) of 8 cmH2O on lung function in newborn rabbit kittens with elevated airway liquid volumes at birth. Near-term rabbits (30 days; term = 32 days) with airway liquid volumes that corresponded to vaginal delivery (∼7 mL/kg, control, n = 11) or cesarean section [∼37 mL/kg; elevated liquid (EL), n = 11] were mechanically ventilated (tidal volume = 8 mL/kg). The PEEP was changed after lung aeration from 0 to 8 to 0 cmH2O (control, n = 6; EL, n = 6), and in a separate group of kittens, PEEP was changed after lung aeration from 8 to 0 to 8 cmH2O (control, n = 5; EL, n = 5). Lung function (ventilator parameters, compliance, lung gas volumes, and distribution of gas within the lung) was evaluated using plethysmography and synchrotron-based phase-contrast X-ray imaging. EL kittens initially receiving 0 cmH2O PEEP had reduced functional residual capacities and lung compliance, requiring higher inflation pressures to aerate the lung compared with control kittens. Commencing ventilation with 8 cmH2O PEEP mitigated the adverse effects of EL, increasing lung compliance, functional residual capacity, and the uniformity and distribution of lung aeration, but did not normalize aeration of the distal airways. Respiratory support with PEEP supports lung function in near-term newborn rabbits with elevated airway liquid volumes at birth who are at a greater risk of suffering respiratory distress.NEW & NOTEWORTHY Term babies born by cesarean section have elevated airway liquid volumes, which predisposes them to respiratory distress. Treatments targeting molecular mechanisms to clear lung liquid are ineffective for term newborn respiratory distress. We showed that respiratory support with an end-expiratory pressure supports lung function in near-term rabbits with elevated airway liquid volumes at birth. This study provides further physiological understanding of lung function in newborns with elevated airway liquid volumes at risk of respiratory distress.

High variability in nurses' tactile stimulation methods in response to apnoea of prematurity-A neonatal manikin study.

AIM: Neonatal intensive care unit (NICU) nurses provide tactile stimulation to terminate apnoea in preterm infants, but guidelines recommending specific methods are lacking. In this study, we evaluated current methods of tactile stimulation performed by NICU nurses. METHODS: Nurses were asked to demonstrate and explain their methods of tactile stimulation on a manikin, using an apnoea scenario. All nurses demonstrated their methods three times in succession, with the manikin positioned either prone, supine or lateral. Finally, the nurses were asked how they decided on the methods of tactile stimulation used. The stimulation methods were logged in chronological order by describing both the technique and the location. The nurses' explanations were transcribed and categorised. RESULTS: In total, 47 nurses demonstrated their methods of stimulation on the manikin. Overall, 57 different combinations of technique and location were identified. While most nurses (40/47, 85%) indicated they learned how to stimulate during their training, 15/40 (38%) of them had adjusted their methods over time. The remaining 7/47 (15%) stated that their stimulation methods were self-developed. CONCLUSION: Tactile stimulation performed by NICU nurses to terminate apnoea was highly variable in both technique and location, and these methods were based on either prior training or intuition.

Automated oxygen control in preterm infants, how does it work and what to expect: a narrative review.

BACKGROUND: Automated oxygen control systems are finding their way into contemporary ventilators for preterm infants, each with its own algorithm, strategy and effect. OBJECTIVE: To provide guidance to clinicians seeking to comprehend automated oxygen control and possibly introduce this technology in their practice. METHOD: A narrative review of the commercially available devices using different algorithms incorporating rule-based, proportional-integral-derivative and adaptive concepts are described and explained. An overview of how they work and, if available, the clinical effect is given. RESULTS: All algorithms have shown a beneficial effect on the proportion of time that oxygen saturation is within target range, and a decrease in hyperoxia and severe hypoxia. Automated oxygen control may also reduce the workload for bedside staff. There is concern that such devices could mask clinical deterioration, however this has not been reported to date. CONCLUSIONS: So far, trials involving different algorithms are heterogenous in design and no head-to-head comparisons have been made, making it difficult to differentiate which algorithm is most effective and what clinicians can expect from algorithms under certain conditions.

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.

Effect of Tactile Stimulation on Termination and Prevention of Apnea of Prematurity: A Systematic Review.

Apnea of prematurity (AOP) is one of the most common diagnoses in preterm infants. Severe and recurrent apneas are associated with cerebral injury and adverse neurodevelopmental outcome. Despite pharmacotherapy and respiratory support to prevent apneas, a proportion of infants continue to have apneas and often need tactile stimulation, mask, and bag ventilation and/or extra oxygen. The duration of the apnea and the concomitant hypoxia and bradycardia depends on the response time of the nurse. We systematically reviewed the literature with the aim of providing an overview of what is known about the effect of manual and mechanical tactile stimulation on AOP. Tactile stimulation, manual or mechanical, has been shown to shorten the duration of apnea, hypoxia, and or bradycardia or even prevent an apnea. Automated stimulation, using closed-loop pulsating or vibrating systems, has been shown to be effective in terminating apneas, but data are scarce. Several studies used continuous mechanical stimulation, with pulsating, vibrating, or oscillating stimuli, to prevent apneas, but the reported effect varied. More studies are needed to confirm whether automated stimulation using a closed loop is more effective than manual stimulation, how and where the automated stimulation should be performed and the potential side effects.

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.