443 - Procedural success and its determinants during minimally invasive surfactant therapy

Poster Number: 443
Publication Number: 443.227

Peter A. Dargaville, Royal Hobart Hospital, Hobart, Tasmania, Australia; C.Omar O. Kamlin, Royal Women's Hospital, Melbourne, Victoria, Australia; Francesca Orsini, MCRI, Melbourne, Victoria, Australia; Antonio De Paoli, Royal Hobart Hospital, Hobart, Tasmania, Australia; Howard W. Clark, University College London, London, England, United Kingdom; Roger F. Soll, Robert Larner, M.D., College of Medicine at the University of Vermont, Hinesburg, VT, United States; John B. Carlin, Murdoch Children's Research Institute & University of Melbourne, Melbourne, Victoria, Australia; Peter G. Davis, University of Melbourne, Melbourne, Victoria, Australia

Background: For the preterm infant with respiratory distress syndrome managed with CPAP, surfactant administration via thin catheter (minimally invasive surfactant therapy, MIST) has emerged as a practicable alternative to intubation for surfactant delivery. There is a paucity of data regarding the factors that influence the success of the MIST procedure.

Objective: To review the influence of demographic, clinical and procedural factors on MIST procedural success using data from the OPTIMIST-A trial (JAMA 2021, 326:2478).

Design/Methods: Trial infants were 25-28 weeks’ gestation, managed with CPAP from the outset and having FiO2 ≥0.30 at an age < 6 h. During MIST, a trained proceduralist inserted a thin catheter into the trachea under larnygoscopic vision, and instilled poractant alfa (200 mg/kg = 2.5 mL/kg) in several aliquots. Up to 3 attempts at catheter insertion were allowed. Positive pressure ventilation (PPV) was to be used in the event of refractory apnoea or protracted hypoxia/bradycardia. For this analysis, we examined the impact of factors having the potential to influence the success of the MIST procedure and the change in FiO2 at 4 h post-procedure. Procedural success was defined as not requiring intubation in the first 4 h post-procedure for escalating oxygen requirement and having an FiO2 at 4 h equal to or below the starting FiO2. Factors included in the analysis were gestation stratum, birth weight < 10th centile, starting FiO2 (at procedure onset), number of catheterisation attempts, need for PPV, and observed surfactant reflux. The influence of these factors on need for intubation in the first 72 h was also examined.

Results: A total of 243 infants received MIST in the trial, at 2.9±1.4 h of age (mean±SD) and a starting FiO2 of 0.38±0.09. Tracheal catheterisation was performed by neonatologists (55 individuals, 170 procedures), senior neonatal trainees (29 individuals, 62 procedures), respiratory therapists (7 individuals, 8 procedures) and neonatal nurse practitioners (3 individuals, 3 procedures). Only 15 (6.2%) of the infants required intubation for escalating oxygen requirement in the first 4 h after MIST. Overall rate of procedural success was high (88%), and was not influenced by any factor examined. Change in FiO2 differed depending on the starting FiO2 (Table 1), but was not influenced by other factors. Need for intubation < 72 h was affected by gestation, growth restriction and starting FiO2, and also trended higher where PPV was needed during the MIST procedure (Table 1).Conclusion(s): MIST was associated with a high rate of procedural success in a range of clinical circumstances.
Table 1.