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

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.

A multicentre neonatal manikin study showed a large heterogeneity in tactile stimulation for apnoea of prematurity

AIM

Apnoea of prematurity requires prompt intervention to prevent long-term adverse outcomes, but specific recommendations about the stimulation approach are lacking. Our study investigated the modalities of tactile stimulation for apnoea of prematurity in different settings.

METHODS

In this multi-country observational prospective study, nurses and physicians of the neonatal intensive care units were asked to perform a tactile stimulation on a preterm neonatal manikin simulating an apnoea. Features of the stimulation (body location and hand movements) and source of learning (training course or clinical practice) were collected.

RESULTS

Overall, 112 healthcare providers from five hospitals participated in the study. During the stimulation, the most frequent location were feet (72%) and back (61%), while the most frequent techniques were rubbing (64%) and massaging (43%). Stimulation modalities different among participants according to their hospitals and their source of learning of the stimulation procedures.

CONCLUSION

There was a large heterogeneity in stimulation approaches adopted by healthcare providers to counteract apnoea in a simulated preterm infant. This finding may be partially explained by the lack of specific guidelines and was influenced by the source of learning for tactile stimulation.

Positive Pressure Ventilation in Preterm Infants in the Delivery Room: A Review of Current Practices, Challenges, and Emerging Technologies

BACKGROUND

A major proportion of preterm neonates require positive pressure ventilation (PPV) immediately after delivery. PPV may be administered through a face mask (FM) or nasal prongs. Current literature indicates that either of these are associated with similar outcomes.

SUMMARY

Nonetheless, FM remains the most utilized and the best choice. However, most available FM sizes are too large for extremely preterm infants, which leads to mask leak and ineffective PPV. Challenges to providing effective PPV include poor respiratory drive, complaint chest wall, weak thoracic muscle, delayed liquid clearance, and surfactant deficiency in preterm infants. Mask leak, airway obstruction, poor technique, and inappropriate size are correctable causes of ineffective PPV. Visual assessment of chest rise is often used to assess the efficacy of PPV. However, its accuracy is debatable. Though end tidal CO2 may adjudge the effectiveness of PPV, clinical studies are limited. The compliance of a preterm lung is highly dynamic. The inflating pressure set on T-piece is constant throughout the resuscitation, but the lung volume and dynamics changes with every breath. This leads to huge fluctuations of tidal volume delivery and can trigger inflammatory cascade in preterm infants leading to brain and lung injury. Respiratory function monitoring in the delivery room has potential for guiding and optimizing delivery room resuscitation. This is, however, limited by high costs, complex information that is difficult to interpret during resuscitation, and absence of clinical trials.

KEY MESSAGES

This review summarizes the existing literature on PPV in preterm infants, the various aspects related to it such as the pathophysiology, interfaces, devices utilized to deliver it, appropriate technique, emerging technologies, and future directions.

Efficacy of a Vibrating Crib Mattress to Reduce Pharmacologic Treatment in Opioid-Exposed Newborns: A Randomized Clinical Trial

Importance

Pharmacologic agents are often used to treat newborns with prenatal opioid exposure (POE) despite known adverse effects on neurodevelopment. Alternative nonpharmacological interventions are needed.

Objective

To examine efficacy of a vibrating crib mattress for treating newborns with POE.

Design, Setting, and Participants

In this dual-site randomized clinical trial, 208 term newborns with POE, enrolled from March 9, 2017, to March 10, 2020, were studied at their bedside throughout hospitalization.

Interventions

Half the cohort received treatment as usual (TAU) and half received standard care plus low-level stochastic (random) vibrotactile stimulation (SVS) using a uniquely constructed crib mattress with a 3-hour on-off cycle. Study initiated in the newborn unit where newborns were randomized to TAU or SVS within 48 hours of birth. All infants whose symptoms met clinical criteria for pharmacologic treatment received morphine in the neonatal intensive care unit per standard care.

Main Outcomes and Measures

The a priori primary outcomes analyzed were pharmacotherapy (administration of morphine treatment [AMT], first-line medication at both study sites [number of infants treated], and cumulative morphine dose) and hospital length of stay. Intention-to-treat analysis was conducted.

Results

Analyses were performed on 181 newborns who completed hospitalization at the study sites (mean [SD] gestational age, 39.0 [1.2] weeks; mean [SD] birth weight, 3076 (489) g; 100 [55.2%] were female). Of the 181 analyzed infants, 121 (66.9%) were discharged without medication and 60 (33.1%) were transferred to the NICU for morphine treatment (31 [51.7%] TAU and 29 [48.3%] SVS). Treatment rate was not significantly different in the 2 groups: 35.6% (31 of 87 infants who received TAU) and 30.9% (29 of 94 infants who received SVS) (P = .60). Adjusting for site, sex, birth weight, opioid exposure, and feed type, infant duration on the vibrating mattress in the newborn unit was associated with reduction in AMT (adjusted odds ratio, 0.88 hours per day; 95% CI, 0.81-0.93 hours per day). This translated to a 50% relative reduction in AMT for infants who received SVS on average 6 hours per day. Among 32 infants transferred to the neonatal intensive care unit for morphine treatment who completed treatment within 3 weeks, those assigned to SVS finished treatment nearly twice as fast (hazard ratio, 1.96; 95% CI, 1.01-3.81), resulting in 3.18 fewer treatment days (95% CI, -0.47 to -0.04 days) and receiving a mean 1.76 mg/kg less morphine (95% CI, -3.02 to -0.50 mg/kg) than the TAU cohort. No effects of condition were observed among infants treated for more than 3 weeks (n = 28).

Conclusions and Relevance

The findings of this clinical trial suggest that SVS may serve as a complementary nonpharmacologic intervention for newborns with POE. Reducing pharmacotherapy with SVS has implications for reduced hospitalization stays and costs, and possibly improved infant outcomes given the known adverse effects of morphine on neurodevelopment.

Trial Registration

ClinicalTrials.gov Identifier: NCT02801331.

Reducing the time delay of oxygen transport to the neonate on continuous positive airway pressure support: A bench study

Background

Premature newborns often require oxygen support as part of their therapy. Systems for oxygen administration are developed to assure adequate oxygenation of newborns. Several factors were identified in the systems that contribute to the time delay between the change in the set inspiratory oxygen fraction and its actual delivery to tissues. In this study, we aimed to reduce the physical delay in oxygen delivery to newborns.

Methods

We developed an O₂ Flush System (O₂-FS) that brings the source of oxygen as close to a patient as possible to make oxygen available for rapid delivery that compensates for the physical delay in the ventilator circuit. The O₂-FS system is built around an electromechanical on/off valve. We validated the O₂-FS concept in experiments with non-invasive Continuous Positive Airways Pressure (CPAP) ventilators.

Results

The O₂-FS accelerated oxygen delivery with all the tested systems and arrangements, typically by 5-15 s. We also observed that the application of supplemental oxygen increased the pressure in the ventilator circuit by 3-4 cmH₂O which may mitigate the apneic pauses that are common in premature newborns.

Conclusions

The O₂-FS system may work as a universal accessory of the CPAP lung ventilator and shorten the distribution of oxygen to the patient during oxygen desaturation events, possibly eliminating or interrupting apneic pauses in neonates, for whom oxygen therapy is an essential treatment. In clinical practice, the O₂-FS could help maintain normoxemic saturation values through adequate oxygen dosing in preterm neonates, thus reducing morbidity and mortality.

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.

Tactile stimulation in very preterm infants and their needs of non-invasive respiratory support

AIM

Despite the lack of evidence, current resuscitation guidelines recommend tactile stimulation in apneic infants within the first minutes of life. The aim was to investigate whether timing, duration or intensity of tactile stimulation influences the extent of non-invasive respiratory support in extremely preterm infants during neonatal resuscitation.

METHODS

In an observational study, we analyzed 47 video recordings and physiological parameters during postnatal transition in preterm infants below 32^0/7 weeks of gestational age. Infants were divided into three groups according to the intensity of respiratory support.

RESULTS

All infants were stimulated at least once during neonatal resuscitation regardless of their respiratory support. Only 51% got stimulated within the first minute. Rubbing the feet was the preferred stimulation method and was followed by rubbing or touching the chest. Almost all very preterm infants were exposed to stimulation and manipulation most of the time within their first 15 min of life. Tactile stimulation lasted significantly longer but stimulation at multiple body areas started later in infants receiving prolonged non-invasive respiratory support.

CONCLUSION

This observational study demonstrated that stimulation of very preterm infants is a commonly used and easy applicable method to stimulate spontaneous breathing during neonatal resuscitation. The concomitant physical stimulation of different body parts and therefore larger surface areas might be beneficial.

Immature control of breathing and apnea of prematurity: the known and unknown

This narrative review provides a broad perspective on immature control of breathing, which is universal in infants born premature. The degree of immaturity and severity of clinical symptoms are inversely correlated with gestational age. This immaturity presents as prolonged apneas with associated bradycardia or desaturation, or brief respiratory pauses, periodic breathing, and intermittent hypoxia. These manifestations are encompassed within the clinical diagnosis of apnea of prematurity, but there is no consensus on minimum criteria required for diagnosis. Common treatment strategies include caffeine and noninvasive respiratory support, but other therapies have also been advocated with varying effectiveness. There is considerable variability in when and how to initiate and discontinue treatment. There are significant knowledge gaps regarding effective strategies to quantify the severity of clinical manifestations of immature breathing, which prevent us from better understanding the long-term potential adverse outcomes, including neurodevelopment and sudden unexpected infant death.

The Importance of Rhythmic Stimulation for Preterm Infants in the NICU

The fetal environment provides the fetus with multiple potential sources of rhythmic stimulation that are not present in the NICU. Maternal breathing, heartbeats, walking, dancing, running, speaking, singing, etc., all bathe the fetus in an environment of varied rhythmic stimuli: vestibular, somatosensory, tactile, and auditory. In contrast, the NICU environment does not offer the same proportion of rhythmic stimulation. After analyzing the lack of rhythmic stimulation in the NICU, this review highlights the different proposals for vestibular and/or auditory rhythmic stimulation offered to preterm infants alone and with their parents. The focus is on the beneficial effects of auditory and vestibular stimulation involving both partners of the mother-infant dyad. A preliminary study on the influence of a skin-to-skin lullaby on the stability of maternal behavior and on the tonic emotional manifestations of the preterm infant is presented as an example. The review concludes with the importance of introducing rhythmic stimulations in the NICU.

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.

An overview of developmental dysregulation of autonomic control in infants

In this short review, we provide an overview of developmental disorders causing autonomic nervous system dysregulation. We briefly discuss perinatal conditions that adversely impact developmental outcomes including apnea of prematurity, sudden infant death syndrome, and Rett syndrome. We provide a brief clinical description, an overview of known or hypothesized mechanisms for the disorder, and current standard of practice for treatment of each condition. Additionally, we consider preventative measures and complications of these disorders to provide further insight into the pathogenesis of specific autonomic dysregulation in neonates. The goal of this short review is to provide an updated understanding of the impact of autonomic dysregulation on development of brainstem circuits and to briefly highlight promising future treatment options and controversies.

Systematic review and meta-analysis suggest that Kangaroo position protects against apnoea of prematurity

AIM

The aim of this study was to determine whether the Kangaroo position decreased apnoea events in preterm newborns compared with conventional care in incubator.

METHODS

We conducted a systematic review of clinical trials published in English, French, Spanish and Portuguese. A comprehensive literature search was realised until 2017. The main outcome was apnoea events. Data were extracted and combined in a fixed-effects model. The quality of the evidence was assessed according to the GRADE framework (grading the quality of evidence and the strength of recommendations).

RESULTS

Four original clinical trials were selected. These trials were conducted in India and Nepal, between 2005 and 2016. The systematic review comprised 416 preterm newborns. Three studies were randomised controlled trials and one was quasi-experimental. Meta-analysis showed a statistically significant reduction in apnoea episodes (relative risk [RR] 0.41; 95% confidence interval [CI] 0.22, 0.78). The result remained significant when only the three clinical trials were analysed (RR 0.43; 95% CI 0.23, 0.83). Quality analysis indicated moderate quality because of lack of an appropriate method of randomisation in one study.

CONCLUSION

The Kangaroo position could have protective effect against apnoea events in preterm infants, decreasing the associated risk of death or long-term disability.

Light or Deep Pressure: Medical Staff Members Differ Extensively in Their Tactile Stimulation During Preterm Apnea

Background: Even though tactile stimulation is common practice to terminate preterm apnea, the style and intensity of these interventions is not specified during theoretical or practical training and has never been clinically evaluated. Objective: The present study was designed to analyze the various modes of tactile stimulation used to terminate preterm apnea and measure the pressure intensity and frequency of these stimulations. Methods: A model with the size and weight of an actual preterm infant was equipped with sensor technology to measure stimulation pressure and frequency of tactile stimulation. Additionally a camera system was used to record hand positions and stimulation modes. Seventy medical staff members took part in the experiment. Results: We found extreme between subjects differences in stimulation pressure that could not be explained by professional experience but, to a degree, depended on apnea intensity. Pressures ranged from 11.11 to 226.87 mbar during low intensity apnea and from 9.89 to 428.15 mbar during high intensity apnea. The majority of participants used rhythmic stimulation movements with a mean frequency of ~1 Hz. Different modes (rubbing, squeezing, tickling, and tapping) and finger positions were used. Conclusion: Medical staff members intuitively adjust their tactile stimulation pressure depending on the premature infants' apnea intensity. However, mean pressure values varied greatly between subjects, with similar pressure ranges for low and high intensity apnea. The question remains which pressure intensities are necessary or sufficient for the task. It is reasonable to assume that some stimulation types may be more effective in rapidly terminating an apneic event.