Propofol versus placebo (with rescue with ketamine) before less invasive surfactant administration: study protocol for a multicenter, double-blind, placebo controlled trial (PROLISA)

Pharmacologic Adjuncts for Neonatal Tracheal Intubation: The Evidence Behind Premedication

Premedication such as analgesia, sedation, vagolytics, and paralytics may improve neonatal tracheal intubation success, reduce intubation-associated adverse events, and create optimal conditions for performing this high-risk and challenging procedure. Although rapid sequence induction including a paralytic agent has been adopted for intubations in pediatric and adult critical care, neonatal clinical practice varies. This review aims to summarize details of common classes of neonatal intubation premedication including indications for use, medication route, dosage, potential adverse effects in term and preterm infants, and reversal agents. In addition, this review shares the literature on national and international practice variations; explores evidence in support of establishing premedication guidelines; and discusses unique circumstances in which premedication use has not been established, such as during catheter-based or minimally invasive surfactant delivery. With increasing survival of extremely preterm infants, clear guidance for premedication use in this population will be necessary, particularly considering potential short- and long-term side effects of procedural sedation on the developing brain.

Alternative routes of surfactant application - An update

Non-invasive modes of respiratory support have been shown to be the preferable way of primary respiratory support of preterm infants with respiratory distress syndrome (RDS). The avoidance of invasive mechanical ventilation can be beneficial for preterm infants in reduction of morbidity and even mortality. However, it is well-established that some infants managed with non-invasive respiratory support from the outset have symptomatic RDS to a degree that warrants surfactant administration. Infants for whom non-invasive respiratory support ultimately fails are prone to adverse outcomes, occurring at a frequency on par with the group intubated primarily. This raises the question how to combine non-invasive respiratory support with surfactant therapy. Several methods of less or minimally invasive surfactant therapy have been developed to address the dilemma between avoidance of mechanical ventilation and administration of surfactant. This paper describes the different methods of less invasive surfactant application, reports the existing evidence from clinical studies, discusses the limitations of each of the methods and the open and future research questions.

Randomized Trial of Surfactant Therapy via Laryngeal Mask Airway Versus Brief Tracheal Intubation in Neonates Born Preterm

OBJECTIVE

To evaluate the possible noninferiority of surfactant administration via laryngeal mask airway (LMA) vs endotracheal tube (ETT) in avoiding the requirement for mechanical ventilation in preterm neonates with respiratory distress syndrome (RDS).

STUDY DESIGN

This was a randomized controlled trial including infants born at 27 to 36 weeks of gestation, >800 g, diagnosed with RDS and receiving fraction of inspired oxygen 0.30-0.60 via noninvasive respiratory support. Infants were randomized to surfactant via LMA (with atropine premedication) or ETT (InSuRE approach with atropine and remifentanil premedication). Primary outcome was failure of surfactant treatment to prevent the need for mechanical ventilation.

RESULTS

Patients were randomized, 51 to LMA and 42 to the ETT group. Both groups had similar baseline characteristics, with birth weights ranging from 810 to 3560 g. Failure rate was 29% in the ETT group and 20% in the LMA group (P = .311). This difference was due to early failures (within 1 hour), with 12.5% in the ETT group and 2% in the LMA group (P = .044). Surfactant therapy via LMA was non-inferior to administration via ETT; failure risk difference -9.0% (CI -∞ to 5.7%). Efficacy in decreasing fraction of inspired oxygen, number of surfactant doses administered, time to wean off all respiratory support, rates of adverse events, and outcomes including pneumothorax and BPD diagnosis did not differ between groups.

CONCLUSIONS

Surfactant therapy via LMA was noninferior to administration via ETT and it decreased early failures, possibly by avoiding adverse effects of premedication, laryngoscopy, and intubation. These characteristics make LMA a desirable conduit for surfactant administration.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02164734.

Sedation for less invasive surfactant administration in preterm infants: a systematic review and meta-analysis

BACKGROUND

Sedation to preterm neonates receiving less invasive surfactant administration (LISA) for respiratory distress syndrome is controversial.

METHODS

Systematic review and meta-analysis of randomized controlled trials (RCTs) and observational studies (OS) to evaluate the effect of sedative drugs for LISA on respiratory outcomes and adverse effects.

RESULTS

One RCT (78 neonates) and two OS (519 neonates) were analyzed in pairwise meta-analysis and 30 studies (2164 neonates) in proportion-based meta-analysis. Sedative drugs might not affect the duration of the procedure [RCT: mean difference (MD) (95% CI); -11 (-90; 67) s; OS: MD 95% CI: -60 (-178; 58) s; low certainty of evidence (CoE)]. Evidence for success at the first attempt and rescue intubation was uncertain (very low CoE). The risk of nasal intermittent positive pressure ventilation [RCT: 1.97 (1.38-2.81); OS: RR, 95% CI: 2.96 (1.46; 6.00), low CoE], desaturation [RCT: RR, 95% CI: 1.30 (1.03; 1.65), low CoE], and apnea [OS: RR, 95% CI: 3.13 (1.35; 7.24), very low CoE] might be increased with sedation. Bradycardia, hypotension, and mechanical ventilation were comparable between groups (low CoE).

CONCLUSIONS

Use of sedative drugs for LISA temporarily affects the newborn's breathing. Further trials are warranted to explore the use of sedation for LISA.

IMPACT

The effect of sedative drugs (analgesics, sedatives, anesthetics) compared to the effect of no-sedation for LISA in preterm infants with RDS is underexplored. This systematic review and meta-analysis assesses the impact of sedative drugs compared to no-sedation for LISA on short-term pulmonary outcomes and potential adverse events. Sedative drugs for LISA temporarily affect the newborn's breathing (desaturation, apnea) and increase the need for nasal intermittent positive pressure ventilation. For most outcomes, certainty of evidence is low/very low.

New modes of surfactant delivery

The provision of exogenous surfactant to premature infants with respiratory distress syndrome has revolutionized the way we care for these patients, significantly improving survival and decreasing morbidity. Currently, the Intubate-SURfactant-Extubate (INSURE) to non-invasive ventilation method remains the standard method for surfactant delivery in the United States. However, the INSURE method requires intubation via direct visualization with a laryngoscope and possible need for sedation. Both carry significant risk to the patients, prompting the development of less invasive ways of safely and efficaciously providing surfactant to newborn infants. The present article reviews and describes the benefits and limitations of several of these alternative methods, including Less Invasive Surfactant Administration (LISA), Minimally Invasive Surfactant Therapy (MIST), via aerosolization, laryngeal mask airway (LMA), and direct nasopharyngeal deposition, focusing on assessment of clinical benefits and the level/risk of invasiveness.

Association of Administration of Surfactant Using Less Invasive Methods With Outcomes in Extremely Preterm Infants Less Than 27 Weeks of Gestation

IMPORTANCE

The inclusion of less invasive surfactant administration (LISA) in the care of preterm infants has been found to be beneficial for respiratory outcomes. Recently, the OPTIMIST trial found higher mortality rates in the subgroup of infants born at 25 to 26 weeks' gestational age (GA) who received surfactant treatment while spontaneously breathing.

OBJECTIVE

To analyze outcomes among LISA-exposed, highly vulnerable babies born at less than 27 weeks' GA within the large-scale observational cohort of the German Neonatal Network.

DESIGN, SETTING, AND PARTICIPANTS

In this cohort study of data from 68 tertiary level neonatal intensive care units in Germany of infants born between 22 weeks 0 days to 26 weeks 6 days of gestation between April 1, 2009, and December 31, 2020, short-term outcomes among infants receiving LISA vs infants not receiving LISA were compared.

EXPOSURE

Use of LISA within the first 72 hours of life.

MAIN OUTCOMES AND MEASURES

The main outcomes were rates of LISA use, use of mechanical ventilation within the first 72 hours (considered failure of LISA), and association of LISA with outcomes, including death from all causes, bronchopulmonary dysplasia (BPD), death and BPD combined, pneumothorax, retinopathy of prematurity, intracerebral hemorrhage, and periventricular leukomalacia. To address potential confounding factors, multivariate logistic regression models were used.

RESULTS

A total of 6542 infants (3030 [46.3%] female and 3512 [53.7%] male; mean [SD] GA, 25.3 (1.1) weeks; mean [SD] birth weight, 715 [180] g) were analyzed; 2534 infants (38.7%) received LISA, which was most frequently given quasi-prophylactically during delivery room management. Among the infants who received LISA, 1357 (53.6%) did not require mechanical ventilation in the first 72 hours compared with 331 infants (8.3%) of 4008 who did not receive LISA. In a multivariate logistic regression model that adjusted for GA, small-for-GA status, sex, multiple birth, inborn status, antenatal steroid use, and maximum fraction of inspired oxygen in the first 12 hours of life, LISA was associated with reduced risks of all-cause death (odds ratio [OR], 0.74; 95% CI, 0.61-0.90; P = .002), BPD (OR, 0.69; 95% CI, 0.62-0.78; P < .001), and BPD or death (OR, 0.64; 95% CI, 0.57-0.72; P < .001) compared with infants without LISA exposure.

CONCLUSIONS AND RELEVANCE

The results of this long-term multicenter cohort study suggest that LISA may be associated with reduced risks of adverse outcomes in extremely preterm infants.

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.

Premedication with Fentanyl for Less Invasive Surfactant Application (LISA): A Randomized Controlled Trial

INTRODUCTION

Currently, there is no consensus regarding analgesic premedication before the surfactant administration by less invasive surfactant application (LISA) procedure. In this randomized controlled trial, we compared the level of comfort of preterm infants receiving fentanyl as analgesic and sedative versus no fentanyl during LISA procedure.

METHODS

We randomized 34 preterm infants of 28+0-33+6 weeks of gestation with respiratory distress syndrome (RDS) within 6 h of birth to receive either fentanyl (1 μg/kg intravenous) or no premedication during surfactant administration by LISA procedure. Primary objective was to assess the proportion of preterm infants to be comfortable during the procedure [revised premature infant pain profile (R-PIPP) score ≤12] and secondarily complications occurring during the procedure, hemodynamically significant patent ductus arteriosus (hsPDA), intraventricular hemorrhage (IVH) (≥ grade 3), bronchopulmonary dysplasia (BPD) and composite outcome of BPD/mortality.

RESULTS

Proportion of preterm infants with a R-PIPP score ≤12 during LISA was significantly higher in the fentanyl group [15/17 (88.23%) vs. 8/17 (47.05%); p value 0.025]. There were no differences in secondary outcome parameters.

CONCLUSION

Low-dose fentanyl during LISA procedure resulted in more comfort in preterm infants and without increased complication of both the LISA procedure and fentanyl administration. Further studies are needed to determine the safest and most effective pharmacologic measures to prevent pain and discomfort during LISA.

Premedication before laryngoscopy in neonates: Evidence-based statement from the French society of neonatology (SFN)

CONTEXT

Laryngoscopy is frequently required in neonatal intensive care. Awake laryngoscopy has deleterious effects but practice remains heterogeneous regarding premedication use. The goal of this statement was to provide evidence-based good practice guidance for clinicians regarding premedication before tracheal intubation, less invasive surfactant administration (LISA) and laryngeal mask insertion in neonates.

METHODS

A group of experts brought together by the French Society of Neonatology (SFN) addressed 4 fields related to premedication before upper airway access in neonates: (1) tracheal intubation; (2) less invasive surfactant administration; (3) laryngeal mask insertion; (4) use of atropine for the 3 previous procedures. Evidence was gathered and assessed on predefined questions related to these fields. Consensual statements were issued using the GRADE methodology.

RESULTS

Among the 15 formalized good practice statements, 2 were strong recommendations to do (Grade 1+) or not to do (Grade 1-), and 4 were discretionary recommendations to do (Grade 2+). For 9 good practice statements, the GRADE method could not be applied, resulting in an expert opinion. For tracheal intubation premedication was considered mandatory except for life-threatening situations (Grade 1+). Recommended premedications were a combination of opioid + muscle blocker (Grade 2+) or propofol in the absence of hemodynamic compromise or hypotension (Grade 2+) while the use of a sole opioid was discouraged (Grade 1-). Statements regarding other molecules before tracheal intubation were expert opinions. For LISA premedication was recommended (Grade 2+) with the use of propofol (Grade 2+). Statements regarding other molecules before LISA were expert opinions. For laryngeal mask insertion and atropine use, no specific data was found and expert opinions were provided.

CONCLUSION

This statement should help clinical decision regarding premedication before neonatal upper airway access and favor standardization of practices.

Surfactant delivery via thin catheters: Methods, limitations, and outcomes

Various less invasive surfactant administration strategies like surfactant replacement therapy via thin catheters, laryngeal mask airway, pharyngeal instillation, and nebulized surfactant are increasingly being practiced to avoid the harmful effects of endotracheal intubation and ventilation. Numerous studies have been done to study surfactant replacement via thin catheters whereas little data is available for other methods. However, there are variations in premedication policies, type of respiratory support used in these studies. Surfactant delivery using thin catheters has been reported to be associated with decrease in the need for mechanical ventilation (MV), duration of MV, bronchopulmonary dysplasia and neonatal mortality. With the current evidence, among all the available surfactant delivery methods, the one using thin catheters appears to be the most feasible and beneficial to improve clinical neonatal outcomes.

Surfactant therapy via thin catheter in preterm infants with or at risk of respiratory distress syndrome

BACKGROUND

Non-invasive respiratory support is increasingly used for the management of respiratory dysfunction in preterm infants. This approach runs the risk of under-treating those with respiratory distress syndrome (RDS), for whom surfactant administration is of paramount importance. Several techniques of minimally invasive surfactant therapy have been described. This review focuses on surfactant administration to spontaneously breathing infants via a thin catheter briefly inserted into the trachea.

OBJECTIVES

Primary objectives In non-intubated preterm infants with established RDS or at risk of developing RDS to compare surfactant administration via thin catheter with: 1. intubation and surfactant administration through an endotracheal tube (ETT); or 2. continuation of non-invasive respiratory support without surfactant administration or intubation. Secondary objective 1. To compare different methods of surfactant administration via thin catheter Planned subgroup analyses included gestational age, timing of intervention, and use of sedating pre-medication during the intervention.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL), in the Cochrane Library; Ovid MEDLINE(R) and Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Daily and Versions(R); and the Cumulative Index to Nursing and Allied Health Literature (CINAHL), on 30 September 2020. We also searched clinical trials databases and the reference lists of retrieved articles for randomised controlled trials (RCTs) and quasi-randomised trials.

SELECTION CRITERIA

We included randomised trials comparing surfactant administration via thin catheter (S-TC) with (1) surfactant administration through an ETT (S-ETT), or (2) continuation of non-invasive respiratory support without surfactant administration or intubation. We also included trials comparing different methods/strategies of surfactant administration via thin catheter. We included preterm infants (at < 37 weeks' gestation) with or at risk of RDS.

DATA COLLECTION AND ANALYSIS

Review authors independently assessed study quality and risk of bias and extracted data. Authors of all studies were contacted regarding study design and/or missing or unpublished data. We used the GRADE approach to assess the certainty of evidence.

MAIN RESULTS

We included 16 studies (18 publications; 2164 neonates) in this review. These studies compared surfactant administration via thin catheter with surfactant administration through an ETT with early extubation (Intubate, Surfactant, Extubate technique - InSurE) (12 studies) or with delayed extubation (2 studies), or with continuation of continuous positive airway pressure (CPAP) and rescue surfactant administration at pre-specified criteria (1 study), or compared different strategies of surfactant administration via thin catheter (1 study). Two trials reported neurosensory outcomes of of surviving participants at two years of age. Eight studies were of moderate certainty with low risk of bias, and eight studies were of lower certainty with unclear risk of bias. S-TC versus S-ETT in preterm infants with or at risk of RDS Meta-analyses of 14 studies in which S-TC was compared with S-ETT as a control demonstrated a significant decrease in risk of the composite outcome of death or bronchopulmonary dysplasia (BPD) at 36 weeks' postmenstrual age (risk ratio (RR) 0.59, 95% confidence interval (CI) 0.48 to 0.73; risk difference (RD) -0.11, 95% CI -0.15 to -0.07; number needed to treat for an additional beneficial outcome (NNTB) 9, 95% CI 7 to 16; 10 studies; 1324 infants; moderate-certainty evidence); the need for intubation within 72 hours (RR 0.63, 95% CI 0.54 to 0.74; RD -0.14, 95% CI -0.18 to -0.09; NNTB 8, 95% CI; 6 to 12; 12 studies, 1422 infants; moderate-certainty evidence); severe intraventricular haemorrhage (RR 0.63, 95% CI 0.42 to 0.96; RD -0.04, 95% CI -0.08 to -0.00; NNTB 22, 95% CI 12 to 193; 5 studies, 857 infants; low-certainty evidence); death during first hospitalisation (RR 0.63, 95% CI 0.47 to 0.84; RD -0.02, 95% CI -0.10 to 0.06; NNTB 20, 95% CI 12 to 58; 11 studies, 1424 infants; low-certainty evidence); and BPD among survivors (RR 0.57, 95% CI 0.45 to 0.74; RD -0.08, 95% CI -0.11 to -0.04; NNTB 13, 95% CI 9 to 24; 11 studies, 1567 infants; moderate-certainty evidence). There was no significant difference in risk of air leak requiring drainage (RR 0.58, 95% CI 0.33 to 1.02; RD -0.03, 95% CI -0.05 to 0.00; 6 studies, 1036 infants; low-certainty evidence). None of the studies reported on the outcome of death or survival with neurosensory disability. Only one trial compared surfactant delivery via thin catheter with continuation of CPAP, and one trial compared different strategies of surfactant delivery via thin catheter, precluding meta-analysis.

AUTHORS' CONCLUSIONS

Administration of surfactant via thin catheter compared with administration via an ETT is associated with reduced risk of death or BPD, less intubation in the first 72 hours, and reduced incidence of major complications and in-hospital mortality. This procedure had a similar rate of adverse effects as surfactant administration through an ETT. Data suggest that treatment with surfactant via thin catheter may be preferable to surfactant therapy by ETT. Further well-designed studies of adequate size and power, as well as ongoing studies, will help confirm and refine these findings, clarify whether surfactant therapy via thin tracheal catheter provides benefits over continuation of non-invasive respiratory support without surfactant, address uncertainties within important subgroups, and clarify the role of sedation.

Less invasive surfactant administration is associated with a higher need for nonpharmacological pain-relieving interventions compared to the intubation-surfactant extubation technique in preterm infants

Aim

LISA is a promising method in improving preterm outcome. The aim of this study was to assess whether the INSURE (intubation-surfactant extubation) technique or LISA (less invasive surfactant administration) procedure for surfactant administration is associated with more pain-relieving interventions after the intervention in preterm infants.

Methods

Preterm infants born at <32 weeks gestational age admitted to the Neonatal Intensive Care Unit of Innsbruck University hospital between Jan 2012 and June 2017 subjected to INSURE or LISA were included in the study, which was performed as a retrospective analysis of routinely collected data. Pain assessments were made bedside using the Bernese Pain Scale for Neonates.

Results

During the study period 15 preterm infants (median gestational age 30.7 weeks; range: 25.9-32.0 weeks) were subjected to INSURE technique and 59 (median gestational age 29.4 weeks; range: 25.1-31.4 weeks) to LISA. Infants subjected to LISA showed a higher need for nonpharmacological pain-relieving interventions in the first three days of life.

Conclusion

LISA procedure compared to INSURE technique was associated with a higher need for pain-relieving interventions in the first three days of life. Prospective randomized controlled trials are needed to optimize this less invasive method for surfactant application with special focus on pain in neonates.

New techniques, new challenges—The dilemma of pain management for less invasive surfactant administration?

Recent years have seen the increasing use of noninvasive respiratory support in preterm infants with the aim of minimizing the risk of mechanical ventilation and subsequent bronchopulmonary dysplasia. Respiratory distress syndrome is the most common respiratory diagnosis in preterm infants, and is best treated by administration of surfactant. Until recently, this has been performed via an endotracheal tube using premedication, which has often included opiate analgesia; subsequently, the infant has been ventilated. Avoidance of mechanical ventilation, however, does not negate the need for surfactant therapy. Less invasive surfactant administration (LISA) in spontaneously breathing infants is increasing in popularity, and appears to have beneficial effects. However, laryngoscopy is necessary, which carries adverse effects and is painful for the infant. Conventional methods of premedication for intubation tend to reduce respiratory drive, which increases the likelihood of ventilation being required. This has led to intense debate about the best strategy for providing appropriate treatment, taking into account both the respiratory needs of the infant and the need to alleviate procedural pain. Currently, clinical practice varies considerably and there is no consensus with respect to optimal management. This review seeks to summarize the benefits, risks, and challenges associated with this new approach.