LISA/MIST: Complex clinical problems almost never have easy solutions

Comparative efficacy and safety of pulmonary surfactant delivery strategies in neonatal RDS: a network meta-analysis

PURPOSE

To compare five pulmonary surfactant (PS) administration strategies for neonates with respiratory distress syndrome (RDS), including intubation-surfactant-extubation (InSurE), thin catheter administration, laryngeal mask airway (LMA), surfactant nebulization (SN), and usual care, with a particular emphasis on the comparison of the LMA and SN with other strategies.

METHODS

We conducted a systematic search of MEDLINE, EMBASE, PUBMED, and Cochrane CENTRAL databases up to November 2023. Two authors independently conducted data extraction, and assessed bias using the Cochrane Risk of Bias Tool. Frequency-based random-effects network meta-analyses were executed.

RESULTS

A total of 36 trials and 4035 infants were included in the analysis. LMA (OR: 0.20, 95%CI: 0.09 to 0.42) and Less Invasive Surfactant Administration (LISA) (OR: 0.17, 95%CI: 0.09 to 0.32) significantly reduced intubation rates compared to usual care. SN had a higher intubation rate compared to LISA (OR: 3.36, 95%CI: 1.46 to 7.71) and LMA (OR: 2.92, 95%CI: 1.10 to 7.71). LMA had a higher incidence of BPD compared to LISA (OR: 2.59, 95%CI: 1.21 to 5.54). SN ranked second to LISA in preventing BPD and death, but its efficacy decreased after excluding high-risk studies. SN and LMA had the lowest incidence of adverse events during administration.SN had the highest likelihood of secondary administration. Most results were rated as low or very low quality, with findings related to SN significantly impacted by high-risk trials.

CONCLUSIONS

The thin catheter strategy minimized intubation risk and showed a better composite effect in reducing both mortality and BPD incidence. SN and LMA each showed safety and some clinical benefits in the subpopulations where they were studied, but their efficacy needs further validation through high-quality studies.

REGISTRATION

 This study was registered in PROSPERO (CRD42023463756).

Less Invasive Surfactant Administration Compared to Intubation, Surfactant, Rapid Extubation Method in Preterm Neonates: An Umbrella Review

INTRODUCTION

In spontaneously breathing neonates, surfactant can be administered via thin catheter while enabling the own breathing (less invasive surfactant administration [LISA]). Alternatively, the neonate is intubated for surfactant delivery (intubation, surfactant, rapid extubation [INSURE]). Thus, the aim was to provide an overview of the efficacy of the LISA compared to INSURE.

METHODS

We performed an umbrella review of previous meta-analyses including randomized controlled trials. We searched PubMed, Scopus, and Web of Science in July 2023. Two authors screened the search results, and systematic reviews with meta-analyses that focused on LISA versus INSURE were included. One author extracted, and another author validated the extracted data. AMSTAR-2 and ROBIS evaluations were performed by two authors independently.

RESULTS

A total of 9 systematic reviews with meta-analyses were included. The quality according to AMSTAR-2 was high in one, moderate in one, low in three, and critically low in four. According to ROBIS, the risk of bias was low in three and high in six of the reviews. LISA was more effective than INSURE in preventing mechanical ventilation (8/8 reviews), death or BPD (4/4 reviews), death (3/9 reviews), and BPD (3/9 reviews).

CONCLUSIONS

All the included systematic reviews and meta-analyses reported LISA to be more effective than INSURE in terms of need for mechanical ventilation and death or BPD. However, the quality of the published systematic reviews has been mostly deficient. Future systematic reviews should focus on reporting quality.

Ultrasound evaluation of diaphragm kinetics after minimally invasive surfactant administration

PURPOSE

Concerns remain on different alveolar deposition of surfactant between LISA and INSURE methods. Ultrasound evaluation of diaphragm kinetics may provide clinical evidence on this issue, as indirect representation of the respiratory system compliance.

METHODS

This was a prospective-observational pilot study. The inclusion criterion was CPAP-supported infants ≤ 32 weeks with RDS receiving surfactant via minimally invasive technique. 52 patients randomized for surfactant administration via LISA or INSURE methods were enrolled. Right diaphragm (RD) global mean peak velocity (MPV) by Pulsed-Wave Tissue Doppler Imaging (PTDI) was recorded before and two hours after surfactant administration with simultaneous measurements of oxygen saturation (SpO2)/fraction of inspired oxygen (FiO2) (SF ratio). Mechanical ventilation ≤ 72 h from birth represented treatment failure.

RESULTS

LISA infants had significantly higher gestational age (p = 0.029) and birth weight (p = 0.030) with lower CRIB-II scores (p = 0.030) than INSURE infants. LISA infants showed higher median MPV at baseline RD-PTDI US assessment (p = 0.024), but post-surfactant median MPV and other the investigated variables were similar at the adjusted analysis for gestational age and sedation. 8/52 (15%) infants who failed treatment had a significantly lower SF ratio (p = 0.002) and higher median MPV at RD-PTDI US (p = 0.004) after surfactant administration, despite the higher CPAP support level before (p = 0.007) and after (p = 0.001) surfactant administration. A full course of antenatal steroids was protective against mechanical ventilation (p = 0.038).

CONCLUSIONS

Different minimally invasive surfactant administration techniques do not appear to influence diaphragm kinetics evaluated by RD-PTDI US.

Curriculum and assessment tool for less invasive surfactant administration: an international Delphi consensus study

BACKGROUND

Training and assessment of operator competence for the less invasive surfactant administration (LISA) procedure vary. This study aimed to obtain international expert consensus on LISA training (LISA curriculum (LISA-CUR)) and assessment (LISA assessment tool (LISA-AT)).

METHODS

From February to July 2022, an international three-round Delphi process gathered opinions from LISA experts (researchers, curriculum developers, and clinical educators) on a list of items to be included in a LISA-CUR and LISA-AT (Round 1). The experts rated the importance of each item (Round 2). Items supported by more than 80% consensus were included. All experts were asked to approve or reject the final LISA-CUR and LISA-AT (Round 3).

RESULTS

A total of 153 experts from 14 countries participated in Round 1, and the response rate for Rounds 2 and 3 was >80%. Round 1 identified 44 items for LISA-CUR and 22 for LISA-AT. Round 2 excluded 15 items for the LISA-CUR and 7 items for the LISA-AT. Round 3 resulted in a strong consensus (99-100%) for the final 29 items for the LISA-CUR and 15 items for the LISA-AT.

CONCLUSIONS

This Delphi process established an international consensus on a training curriculum and content evidence for the assessment of LISA competence.

IMPACT

This international consensus-based expert statement provides content on a curriculum for the less invasive surfactant administration procedure (LISA-CUR) that may be partnered with existing evidence-based strategies to optimize and standardize LISA training in the future. This international consensus-based expert statement also provides content on an assessment tool for the LISA procedure (LISA-AT) that can help to evaluate competence in LISA operators. The proposed LISA-AT enables standardized, continuous feedback and assessment until achieving proficiency.

Prevention of Chronic Morbidities in Extremely Premature Newborns with LISA-nCPAP Respiratory Therapy and Adjuvant Perinatal Strategies

Less invasive surfactant administration techniques, together with nasal continuous airway pressure (LISA-nCPAP) ventilation, an emerging noninvasive ventilation (NIV) technique in neonatology, are gaining more significance, even in extremely premature newborns (ELBW), under 27 weeks of gestational age. In this review, studies on LISA-nCPAP are compiled with an emphasis on short- and long-term morbidities associated with prematurity. Several perinatal preventative and therapeutic investigations are also discussed in order to start integrated therapies as numerous organ-saving techniques in addition to lung-protective ventilations. Two thirds of immature newborns can start their lives on NIV, and one third of them never need mechanical ventilation. With adjuvant intervention, these ratios are expected to be increased, resulting in better outcomes. Optimized cardiopulmonary transition, especially physiologic cord clamping, could have an additively beneficial effect on patient outcomes gained from NIV. Organ development and angiogenesis are strictly linked not only in the immature lung and retina, but also possibly in the kidney, and optimized interventions using angiogenic growth factors could lead to better morbidity-free survival. Corticosteroids, caffeine, insulin, thyroid hormones, antioxidants, N-acetylcysteine, and, moreover, the immunomodulatory components of mother's milk are also discussed as adjuvant treatments, since immature newborns deserve more complex neonatal interventions.

Rigid versus soft catheter for less invasive surfactant administration: A crossover randomized controlled manikin trial

BACKGROUND

We compared surfactant administration with a rigid versus soft catheter in a manikin simulating an extremely preterm infant.

METHODS

Randomized controlled crossover (AB/BA) trial. Fifty tertiary hospital consultants and pediatric residents. The primary outcome was the time of device positioning. The secondary outcomes were the success of the first attempt, the number of attempts, and the participant's opinion.

RESULTS

Median time of device positioning was 19 s (interquartile range [IQR]: 15-25) with rigid catheter and 40 s (IQR: 28-66) with soft catheter (p < 0.0001). Success at first attempt was 92% with rigid catheter and 74% with soft catheter (p = 0.01). Median number of attempts was 1 (IQR: 1-1) with rigid catheter and 1 (IQR: 1-2) with soft catheter (p = 0.009). Participants found the rigid catheter easier to use (p < 0.0001).

CONCLUSIONS

In a preterm manikin model, using a rigid catheter for less invasive surfactant administration was quicker and easier to use than a soft catheter.

Respiratory Management of the Preterm Infant: Supporting Evidence-Based Practice at the Bedside

Extremely preterm infants frequently require some form of respiratory assistance to facilitate the cardiopulmonary transition that occurs in the first hours of life. Current resuscitation guidelines identify as a primary determinant of overall newborn survival the establishment, immediately after birth, of adequate lung inflation and ventilation to ensure an adequate functional residual capacity. Any respiratory support provided, however, is an important contributing factor to the development of bronchopulmonary dysplasia. The risks correlated to invasive ventilatory techniques increase inversely with gestational age. Preterm infants are born at an early stage of lung development and are more susceptible to lung injury deriving from mechanical ventilation. Any approach aiming to reduce the global burden of preterm lung disease must implement lung-protective ventilation strategies that begin from the newborn’s first breaths in the delivery room. Neonatologists today must be able to manage both invasive and noninvasive forms of respiratory assistance to treat a spectrum of lung diseases ranging from acute to chronic conditions. We searched PubMed for articles on preterm infant respiratory assistance. Our narrative review provides an evidence-based overview on the respiratory management of preterm infants, especially in the acute phase of neonatal respiratory distress syndrome, starting from the delivery room and continuing in the neonatal intensive care unit, including a section regarding exogenous surfactant therapy.

Device positioning with LISA vs. INSURE: a crossover randomized controlled manikin trial

OBJECTIVE

We aimed to compare time of device positioning, success of procedure and operator's opinion with LISA vs. INSURE in a manikin simulating an extremely low birthweight infant.

METHODS

A randomized controlled crossover (AB/BA) trial of surfactant administration with LISA vs. INSURE in a preterm manikin. Forty-two tertiary hospital consultants and pediatric residents with previous experience with LISA and INSURE participated. The primary outcome measure was the time of device positioning. The secondary outcome measures were: success of the first attempt, number of attempts, correct depth, and participant's opinion on difficulty in using the device.

RESULTS

Median time of device positioning was shorter with LISA vs. INSURE (median difference -8 s, 95% confidence interval -16 to -1 s; p = .04). Success at first attempt was 35/40 with LISA (83%) and 31/40 with INSURE (74%) (p = .42). Median number of attempts was 1 (IQR 1-1) with LISA and 1 (IQR 1-2) with INSURE (p = .08). Correct depth was achieved in 30/40 with LISA (71%) and 37/40 with INSURE (88%) (p = .12). Participants found LISA easier to insert in the trachea (p = .002) but INSURE easier to place at the correct depth (p = .008). Handling the device (p = .43), visualizing the glottis (p = .17) and overall difficulty in using the device (p = .13) were not statistically different.

CONCLUSIONS

In a preterm manikin model, positioning a thin catheter (LISA) was quicker and easier than a tracheal tube (INSURE), but the magnitude of the difference was unlikely to be clinically relevant and the tracheal tube was easier to place at the correct depth.

REGISTRATION

clinicaltrial.gov NCT04944108.

Early surfactant and non-invasive ventilation versus intubation and surfactant: a propensity score-matched national study

OBJECTIVE

To compare outcome after less invasive surfactant administration (LISA) and primary endotracheal intubation (non-LISA) in infants born before gestational age (GA) 28 weeks.

SETTING

All neonatal intensive care units (NICUs) in Norway during 2012-2018.

METHODS

Defined population-based data were prospectively entered into a national registry. We compared LISA infants with all non-LISA infants and with non-LISA infants who received surfactant following intubation. We used propensity score (PS) matching to identify non-LISA infants who were similar regarding potential confounders.

MAIN OUTCOME VARIABLES

Rate and duration of mechanical ventilation (MV), survival, neurological and gastrointestinal morbidity, and need of supplemental oxygen or positive pressure respiratory support at postmenstrual age (PMA) 36 and 40 weeks.

RESULTS

We restricted analyses to GA 25-27 weeks (n=843, 26% LISA) because LISA was rarely used at lower GAs. There was no significant association between NICUs regarding proportions treated with LISA and proportions receiving MV. In the PS-matched datasets, fewer LISA infants received MV (61% vs 78%, p<0.001), and they had fewer days on MV (mean difference 4.1, 95% CI 0.0 to 8.2 days) and lower mortality at PMA 40 weeks (absolute difference 6%, p=0.06) compared with all the non-LISA infants, but only a lower rate of MV (64% vs 97%, p<0.001) and fewer days on MV (mean difference 5.8, 95% CI 0.6 to 10.9 days) compared with non-LISA infants who received surfactant after intubation.

CONCLUSION

LISA reduced the rate and duration of MV but had no other clear benefits.

Alternative Methods of Surfactant Administration in Preterm Infants with Respiratory Distress Syndrome: State of the Art

For preterm infants with respiratory distress syndrome, delivery of surfactant via brief intubation (INtubate, SURfactant, Extubate; InSurE) has been the standard technique of surfactant administration. However, this method requires intubation and positive pressure ventilation. It is thought that even the short exposure to positive pressure inflations may be enough to initiate the cascade of events that lead to lung injury in the smallest neonates. In an effort to avoid tracheal intubation and positive pressure ventilation, several alternative and less invasive techniques of exogenous surfactant administration have been developed over the years. These have been investigated in clinical studies, including randomized clinical trials, and have demonstrated advantages such as a decrease in the need for mechanical ventilation and incidence of bronchopulmonary dysplasia. These newer techniques of surfactant delivery also have the benefit of being easier to perform. Surfactant delivery via pharyngeal instillation, laryngeal mask, aerosolization, and placement of a thin catheter are being actively pursued in research. We present a contemporary review of surfactant administration for respiratory distress syndrome via these alternative methods in the hope of guiding physicians in their choices for surfactant application in the neonatal intensive care unit.

An educational programme in neonatal intensive care units (SEPREVEN): a stepped-wedge, cluster-randomised controlled trial

BACKGROUND

Patients in neonatal intensive care units (NICUs) are at high risk of adverse events. The effects of medical and paramedical education programmes to reduce these have not yet been assessed.

METHODS

In this multicentre, stepped-wedge, cluster-randomised controlled trial done in France, we randomly assigned 12 NICUs to three clusters of four units. Eligible neonates were inpatients in a participating unit for at least 2 days, with a postmenstrual age of 42 weeks or less on admission. Each cluster followed a 4-month multifaceted programme including education about root-cause analysis and care bundles. The primary outcome was the rate of adverse events per 1000 patient-days, measured with a retrospective trigger-tool based chart review masked to allocation of randomly selected files. Analyses used mixed-effects Poisson modelling that adjusted for time. This trial is registered with ClinicalTrials.gov, NCT02598609.

FINDINGS

Between Nov 23, 2015, and Nov 2, 2017, event rates were analysed for 3454 patients of these 12 NICUs for 65 830 patient-days. The event rate per 1000 patient-days reduced significantly from the control to the intervention period (33·9 vs 22·6; incidence rate ratio 0·67; 95% CI 0·50-0·88; p=0·0048).

INTERPRETATION

A multiprofessional safety-promoting programme in NICUs reduced the rate of adverse events and severe and preventable adverse events in highly vulnerable patients. This programme could significantly improve care offered to critically ill neonates.

FUNDING

Solidarity and Health Ministry, France.

Enhanced INSURE (ENSURE): an updated and standardised reference for surfactant administration

There is no firm consensus about the optimal technique for the administration of exogenous surfactant in preterm neonates, and different techniques may be equally effective. The intubation-surfactant-extubation (INSURE) procedure has not been fully described, and important details, such as duration and mode of ventilation, remain unclear, leading to significant clinical practice variations and influencing its suitability and feasibility. Since the first INSURE description, our knowledge in respiratory care has largely progressed, but the technique has not been updated according to current evidence-based practice. Thus, our aim is to formally describe a modern way to perform INSURE, based on the current knowledge and technology, to increase its feasibility and patients' safety. We offer ENSURE (Enhanced INSURE) as an updated and standardised technique for surfactant administration, clarifying crucial issues of the original method by applying current state-of-the-art concepts of respiratory care. We performed a cross-sectional observational study enrolling 57 preterm neonates describing ENSURE feasibility and safety.   Conclusion: ENSURE can be used as a reference technique in clinical practice, teaching and research. What is Known: • There is no consensus about the optimal method for surfactant administration. INSURE technique has been originally described many years ago without considering modern principles of neonatal respiratory care and the available state-of-the-art technology. What is New: • We here describe a modern way to perform INSURE, based on the current knowledge and technology. We called it ENSURE (Enhanced INSURE) and clarified crucial points of the original technique, in light of the current knowledge. We verified feasibility and safety of ENSURE in a cross-sectional observational study enrolling 57 preterm neonates.

Techniques to evaluate surfactant activity for a personalized therapy of RDS neonates

According to both European and American Guidelines, preterm neonates have to be treated by nasal continuous air pressure (CPAP) early in the delivery room. The administration of surfactant should be reserved only for babies with respiratory distress syndrome (RDS) with increased oxygen requirement, according to different thresholds of FiO₂. However, these oxygenation thresholds do not fully take into consideration the lung physiopathology and mechanics or the lung surfactant biology of RDS neonates. Since surfactant replacement therapy (SRT) seems to be more effective if it is initiated within the first 3 hours after birth, the use of a reliable bench-to-bedside biological test able to predict as soon as possible the necessity of SRT will help optimise individualised therapies and personalise the actual collective strategy used to treat RDS neonates. With this in mind, in the present review several quantitative and qualitative biological tests to assess the surfactant status in RDS neonates are introduced as potential candidates for the early prediction of SRT requirement, summarising the state-of-the-art in the evaluation of surfactant activity.