# Dexmedetomidine for LISA procedure: a prospective observational single center experience

## TL;DR

This study evaluates the use of dexmedetomidine for sedation during a procedure to treat respiratory distress in preterm infants, finding it effective for pain control but inconsistent for sedation.

## Contribution

The study provides a novel observational assessment of dexmedetomidine's efficacy and safety for LISA in preterm neonates.

## Key findings

- Dexmedetomidine provided adequate pain control in 76% of cases during laryngoscopy.
- Laryngoscopy conditions were adequate in 90% of neonates.
- Adverse events like apnea/desaturation occurred in 13% of newborns.

## Abstract

Respiratory Distress Syndrome (RDS) is the most common respiratory problem of preterm newborns. The preferred way to manage RDS is with Less Invasive Surfactant Administration (LISA), which involves direct laryngoscopy in spontaneously breathing infants. Despite its widespread diffusion, the optimal sedation protocol for LISA remains unclear. Dexmedetomidine, an α2-adrenergic agonist, offers sedative and analgesic properties with minimal respiratory depression. This pilot study aims to evaluate dexmedetomidine for LISA procedure focusing on the frequency of adequate sedation (defined as N-PASS score −2 to −5) and analgesia (NIPS score < 4) and adverse events related to dexmedetomidine.

This is a prospective observational study conducted in our tertiary Italian NICU from May 2021 to July 2024. We enrolled preterm neonates aged between 26+0 to 36+6 weeks, diagnosed with RDS who required LISA. We also analyzed the study population into two groups based on a cut-off of 32 weeks to understand possible differences in adverse events and sedation and analgesia scores, even if this was not our prior aim. Dexmedetomidine (1 µg/kg) was administered intravenously before LISA. Primary outcomes included pain control assessed by Neonatal Infant Pain Scale (NIPS) score, sedation adequacy assessed by Neonatal Pain, Agitation, and Sedation Scale (N-PASS), and success rate of the procedure (such as laryngoscopy conditions assessed by Goldberg score and number of attempts). We also assessed the safety of the procedure evaluating adverse events, such as intubation rates, apneas/desaturations, bradycardia, and hypotension.

Forty-seven preterm newborns received dexmedetomidine. The median (IQR) gestational age (weeks/days), birth weight (grams) and age (hours) at LISA were respectively 29+6 (28+5, 33+1) weeks, 1421 (1069–2074) g, 3 (2.5–6) hours. Pain scores indicated adequate pain control during the procedure (NIPS < 4 in 76% during laryngoscopy). Light sedation (N-PASS −2 to −5) was observed in 23% of patients before the procedure, lasting up to 60 minutes. Excessive sedation (N-PASS −6 to −10) occurred in 7% of babies (3 patients). Laryngoscopy conditions were adequate in 90% of neonates (Goldberg score < 6). Apnea/desaturation with/without bradycardia occurred in 13% of newborns. Six patients were intubated (13%) within 72 hours after the procedure. Hypotension was noted in 6.4% of patients.

Premedication with dexmedetomidine resulted in a good success rate for pain control; however, an adequate level of sedation was not consistently achieved. While the frequency of adverse events was acceptable, a more rapid-onset sedative may be preferable for this procedure. Further randomized controlled trials are needed to establish an optimal sedation strategy for LISA in preterm newborns.

Register: ClinicalTrials.gov, number ID NCT04820101, enregistered 03–29-2021, https://clinicaltrials.gov/study/NCT04820101?cond = RDS&term =dexmedetomidine&rank = 1#study-record-dates .