Impact of Catheter Choice on Procedural Success of Minimally Invasive Surfactant Therapy.

OBJECTIVE: Surfactant delivery via a thin endotracheal catheter during spontaneous breathing; a technique called minimally invasive surfactant therapy (MIST) is an alternative to intubation and surfactant administration. Procedural details among different centers vary, with marked differences in the choice of catheter to instill surfactant. Studies report use of feeding catheters, multiaccess suction catheters, vascular catheters, and more recently custom-built catheters for this purpose. The impact of choice of catheter on procedural success and procedural adverse effects has not been reported. Our present study compares the procedural success and adverse effects of MIST using a semirigid vascular catheter (16G Angiocath-Hobart Method) versus a flexible multiaccess catheter (MAC). STUDY DESIGN: This was a retrospective review of prospectively collected data at a tertiary care neonatal intensive care unit in Southwestern Ontario. All neonates who received surfactant via MIST between May 1, 2016 and September 30, 2020 were included in the study. Relevant baseline characteristics and data on procedural details (premedication, type of catheter, etc.) were collected. The procedural success, number of attempts, and adverse effects between neonates who received MIST via MAC and 16G Angiocath was compared by using Chi-square test or Fisher's test as appropriate. A p-value of less that 0.05 was considered significant. RESULTS: A total of 139 neonates received surfactant via MIST method during the study period. Moreover, 93 neonates received the surfactant via MAC, while 46 received it via Angiocath. The baseline demographic characteristics in the two group were similar. A higher proportion of neonates in Angiocath group received Atropine (100 vs. 76%, p = 0.002) and Fentanyl (98 vs. 36%, p < 0.001) than the MAC group.The procedural success was 91% in the Angiocath group and 89% in the MAC group (p > 0.99). Multiple attempts were needed in 24% of neonates in the Angiocath group and 37% in the MAC group (p = 0.158). More episodes of desaturations were noted in the Angiocath group (89%) than the MAC group (69%; p = 0.012). Other rates of common adverse effects were similar between the two groups. On exploratory analysis fentanyl use held significant association with less success, more desaturation, apneic episodes, and need of positive pressure ventilation /intubation. CONCLUSION: The overall procedural success of MIST is similar in both catheter groups. The proportion of neonates requiring multiple attempts was lower with the Angiocath, though difference was not statistically significant. Desaturation episodes were seen more frequently in the Angiocath group, which was related to higher use of procedural sedation in this group. KEY POINTS: · MIST is emerging as a less invasive method of surfactant delivery that has proven clinical benefits.. · Considerable, procedural variation is reported, particularly regarding choice of catheter.. · Our present study compares the procedural success and adverse effects of MIST using a semirigid vascular catheter (16G Angiocath-Hobart method) versus a flexible MAC.. · High and comparable procedural success was seen in both groups..

A survey of minimally invasive surfactant therapy in Canada.

Introduction: Minimally invasive surfactant therapy (MIST) can be used to treat neonatal respiratory distress syndrome in neonatal intensive care units (NICUs). Clinical and institutional variances in MIST utilization persist globally with little published research regarding MIST utilization in Canada. Therefore, the objective of this study was to survey MIST utilization in NICUs in Canada. Methods: An online survey was emailed to the 33 participating centres of Canadian Neonatal NetworkTM (CNN) Evidence-based Practice for Improving Quality (EPIQ) Lung Health Group (LHG). Site demographics and surfactant therapy procedural details were categorically collected. Free text and multiple-choice questions were utilized to capture perceived barriers and individual preferences for MIST use. Results: Twenty-eight of 33 participating members of the CNN EPIQ-LHG completed the survey between April 2021 and October 2021 (85%); 17/28 (61%) respondents reported ongoing MIST utilization at their center. Most centers that used MIST techniques administered bovine lipid extract surfactant (68%), commonly using angiocatheters (47%) and purpose-built catheters (41%). MIST was widely used for patients at 26-33 weeks gestational age (88%). Nine centres had never used MIST (32%), and 3 indicated a plan to implement MIST within the next 2 years. Common barriers to MIST use included lack of consensus amongst clinicians (78%), lack of training (56%), and lack of experience with MIST (56%). Conclusion: While MIST is being increasingly used in Canadian NICUs, universal use is yet to be seen. Clinician inexperience and lack of consensus, formal training, and local guidelines contribute to underutilization of MIST. Training workshops, country-wide data collection, and uniform operating protocols are needed to standardize practice.

Airway injury and pneumomediastinum associated with less invasive surfactant administration in a premature neonate: a case report.

BACKGROUND: The use of less invasive surfactant administration (LISA)/minimally invasive surfactant therapy (MIST) has increased due to its potential advantage over traditional surfactant delivery methods through an endotracheal tube. Known complications for this procedure include failure of the first attempt at insertion, desaturation, and bradycardia. To the best of our knowledge, this is the first reported case of pneumomediastinum and subcutaneous emphysema following LISA. CASE PRESENTATION: A preterm newborn born at 27 weeks of gestation presented with respiratory distress syndrome requiring surfactant replacement. LISA using the Hobart method was completed. There was a report of procedural difficulty related to increased resistance to insertion of the 16G angiocath. The newborn was subsequently noted to have subcutaneous emphysema over the anterior aspect of the neck and substantial pneumomediastinum on radiological assessment. Associated complications included hypotension requiring inotropic support. The newborn was successfully managed conservatively, with complete resolution of the air leak. CONCLUSIONS: Upper airway injury leading to air leak syndrome is a rare complication of the Hobart method for LISA. Awareness of such procedural complications is important as the use of the LISA method increases.

High-volume surfactant administration using a minimally invasive technique: Experience from a Canadian Neonatal Intensive Care Unit.

BACKGROUND: Surfactant delivery via a thin endotracheal catheter during spontaneous breathing, a technique called minimally invasive surfactant therapy (MIST), is an alternative to intubation and surfactant administration. There is paucity of data regarding the administration of high-volume surfactant using this technique. METHODS: We conducted a retrospective cohort study to review the safety, efficacy, and procedural details pertaining to the delivery of 5 mL/kg of BLES® via MIST approach. In 2016, our centre initiated a practice change allowing the use of MIST as an alternative method of surfactant delivery in infants born at ≥28 weeks and/or with a birth weight ≥ 1,000 g with respiratory distress syndrome. In this study, we identified all neonates who received surfactant via MIST between May 1, 2016 and July 30, 2018 and collected relevant procedural data. RESULTS: Since this practice change, MIST technique was attempted in 43 neonates with successful instillation of surfactant in 41 (95.3%) of the neonates. Intubation and positive pressure ventilation was avoided in 35 neonates (85.3%). No serious adverse effect was noted. CONCLUSIONS: Our study reports successful use of higher volume surfactant via MIST. This should encourage other similar centres to consider this technique, in order to avoid unnecessary intubation and positive pressure ventilation.

Survey of noninvasive respiratory support practices in Canadian neonatal intensive care units.

AIM: To evaluate practice variation with respect to noninvasive respiratory support (NRS) use across Canadian neonatal intensive care units (NICUs). METHODS: A web-based survey was sent to all site investigators of the 30 level 3 NICUs participating in the Canadian Neonatal Network. The survey inquired about the use of five commonly described NRS modes. In addition, the presence and adherence to local guidelines were ascertained. Descriptive analyses were performed to identify variations in practice. RESULTS: In total, 28 (93%) of the 30 tertiary NICUs responded to the survey. Continuous positive airway pressure (CPAP) was employed universally (100%). High-flow nasal cannula (HFNC) was used in 89% of NICUs, biphasic CPAP in 79% and nasal intermittent positive pressure ventilation (NIPPV) in 54%, and nasal high-frequency ventilation was used in 18% of units. Only 61% of all NRS use was guided by local policies, with the lowest being for HFNC (36%). There was a wide range of settings employed and interfaces used for all NRS modes. CONCLUSION: There are significant practice variations in NRS use across Canadian NICUs. Further research is needed to evaluate the significance in relation to pulmonary outcomes to determine optimal NRS strategies.

A Pilot Randomized Trial Comparing Weaning From Mechanical Ventilation on Pressure Support Versus Proportional Assist Ventilation.

OBJECTIVES: Despite protocols incorporating spontaneous breathing trials, 31% of ICU patients experience difficult or prolonged weaning from mechanical ventilation. Nonfatiguing modes such as pressure support ventilation are recommended. Proportional assist ventilation provides assistance in proportion to patient effort, which may optimize weaning. However, it is not known how proportional assist ventilation performs relative to pressure support ventilation over a prolonged period in the complex ICU setting. The purpose of this study was to compare the physiologic and clinical performance (failure rate), safety, and feasibility of protocols using daily spontaneous breathing trial plus pressure support ventilation versus proportional assist ventilation until ventilation discontinuation. DESIGN: Single-center, unblinded pilot randomized controlled trial. SETTING: Medical-surgical ICU of a tertiary-care hospital. PATIENTS: Adult patients intubated greater than 36 hours were randomized if they met eligibility criteria for partial ventilatory support, tolerated pressure support ventilation greater than or equal to 30 minutes, and either failed or did not meet criteria for a spontaneous breathing trial. INTERVENTIONS: Patients were randomized to the pressure support ventilation or proportional assist ventilation protocol (PAV+, Puritan Bennett 840; Covidien, Boulder, CO). Both protocols used progressive decreases in level of assistance as tolerated, coupled with daily assessment for spontaneous breathing trials. MEASUREMENTS AND MAIN RESULTS: Of 54 patients randomized, outcome data are available for 50 patients; 27 were randomized to receive proportional assist ventilation and 23 to receive pressure support ventilation. There were no adverse events linked to the study interventions, and protocol violations were infrequent. Recruitment was slower than projected (1.3 patients per month). The median (interquartile range) time from randomization to successful extubation was 3.9 days (2.8-8.4 d) on proportional assist ventilation versus 4.9 days (2.9-26.3 d) on pressure support ventilation (p = 0.39). Time to live ICU discharge was 7.3 days (5.2-11.4 d) on proportional assist ventilation versus 12.4 days (7.5-30.8 d) on pressure support ventilation (p = 0.03). CONCLUSION: This pilot study demonstrates the utility, safety, and feasibility of the weaning protocols and provides important information to guide the design of a future randomized controlled trial comparing weaning from mechanical ventilation on pressure support ventilation versus proportional assist ventilation.

Evaluation of a practice guideline for the management of respiratory distress syndrome in preterm infants: A quality improvement initiative.

BACKGROUND: The use of mechanical ventilation to treat respiratory distress syndrome in preterm infants has been associated with the development of bronchopulmonary dysplasia. As part of a quality improvement initiative to reduce the incidence of bronchopulmonary dysplasia in preterm infants, a new practice guideline for the management of respiratory distress syndrome was developed and adopted into practice in a neonatal intensive care unit in February 2012. OBJECTIVE: To evaluate the effects of implementing the new guideline in regard to the use of mechanical ventilation and surfactant, and the incidence of bronchopulmonary dypslasia. METHODS: An historical cohort of very preterm infants (gestational age 26(0) to 32(6) weeks) born one year before guideline implementation was compared with a similar cohort of infants born one year following guideline implementation. Data were collected retrospectively from the local neonatal intensive care unit database. RESULTS: A total of 272 preterm infants were included in the study: 129 in the preguideline cohort and 143 in the postguideline cohort. Following the implementation of the guideline, the proportion of infants treated with ongoing mechanical ventilation was reduced from 49% to 26% (P<0.001) and there was a trend toward a reduction in bronchopulmonary dysplasia (27% versus 18%; P=0.07). There was no difference in the proportion of infants treated with surfactant (54% versus 50%). CONCLUSION: The implementation of the practice guideline helped to minimize the use of ongoing mechanical ventilation in preterm infants.

HISTORIQUE: La ventilation mécanique utilisée pour traiter le syndrome de détresse respiratoire chez les nourrissons prématurés s'associe à l'apparition d'une dysplasie bronchopulmonaire (DBP). Dans le cadre d'une initiative d'amélioration de la qualité pour réduire l'incidence de DBP chez les nourrissons prématurés, de nouvelles directives cliniques pour la prise en charge du syndrome de détresse respiratoire ont été rédigées et adoptées en février 2012 dans une unité de soins intensifs néonatale. OBJECTIF: Évaluer les effets de l'adoption des nouvelles directives sur l'utilisation de la ventilation mécanique et du surfactant et sur l'incidence de DBP. MÉTHODOLOGIE: Les chercheurs ont comparé une cohorte historique de nourrissons très prématurés (de 260 à 326 semaines d'âge gestationnel) nés un an avant l'adoption des directives à une cohorte similaire de nourrissons nés un an après l'adoption des directives. Ils ont procédé à la collecte rétrospective des données dans la base de données de l'unité de soins intensifs néonatals locale. RÉSULTATS: Au total, 272 nourrissons prématurés ont été inclus dans l'étude, soit 129 de la cohorte d'avant les directives et 143 de la cohorte d'après les directives. Après l'adoption des directives, la proportion de nourrissons traités par ventilation mécanique continue est passée de 49 % à 26 % (P<0,001), et on a constaté une tendance vers la diminution des DBP (27 % par rapport à 18 %, P=0,07). Il n'y avait pas de différence dans la proportion de nourrissons traités au surfactant (54 % par rapport à 50 %). CONCLUSION: L'adoption des directives cliniques a contribué à réduire le recours à la ventilation mécanique chez les nourrissons prématurés.

CPAP Versus NIPPV Postextubation in Preterm Neonates: A Comparative-Effectiveness Study.

BACKGROUND AND OBJECTIVES: Nasal intermittent positive pressure ventilation (NIPPV) has been shown to be superior to nasal continuous positive airway pressure (CPAP) postextubation in preterm neonates. However, studies have not permitted high CPAP pressures or rescue with other modes. We hypothesized that if CPAP pressures >8 cmH2O and rescue with other modes were permitted, CPAP would be noninferior to NIPPV. METHODS: We conducted a pragmatic, comparative-effectiveness, noninferiority study utilizing network-based real-world data from 22 Canadian NICUs. Centers self-selected CPAP or NIPPV as their standard postextubation mode for preterm neonates <29 weeks' gestation. The primary outcome was failure of the initial mode ≤72 hours. Secondary outcomes included failure ≤7 days, and reintubation ≤72 hours and ≤7 days. Groups were compared using a noninferiority adjusted risk-difference (aRD) margin of 0.05, and margin of no difference. RESULTS: A total of 843 infants extubated to CPAP and 974 extubated to NIPPV were included. CPAP was not noninferior (and inferior) to NIPPV for failure of the initial mode ≤72 hours (33.0% vs 26.3%; aRD 0.07 [0.03 to 0.12], Pnoninferiority(NI) = .86), and ≤7 days (40.7% vs 35.8%; aRD 0.09 [0.05 to 0.13], PNI = 0.97). However, CPAP was noninferior (and equivalent) to NIPPV for reintubation ≤72 hours (13.2% vs 16.1%; aRD 0.01 [-0.05 to 0.02], PNI < .01), and noninferior (and superior) for reintubation ≤7 days (16.4% vs 22.8%; aRD -0.04 [-0.07 to -0.001], PNI < .01). CONCLUSIONS: CPAP was not noninferior to NIPPV for failure ≤72 hours postextubation; however, it was noninferior to NIPPV for reintubation ≤72 hours and ≤7 days. This suggests CPAP may be a reasonable initial postextubation mode if alternate rescue strategies are available.

Duration of and trends in respiratory support among extremely preterm infants.

OBJECTIVE: To evaluate annual trends in the administration and duration of respiratory support among preterm infants. DESIGN: Retrospective cohort study. SETTING: Tertiary neonatal intensive care units in the Canadian Neonatal Network. PATIENTS: 8881 extremely preterm infants born from 2010 to 2017 treated with endotracheal and/or non-invasive positive pressure support (PPS). MAIN OUTCOME MEASURES: Competing risks methods were used to investigate the outcomes of mortality and time to first successful extubation, definitive extubation, weaning off PPS, and weaning PPS and/or low-flow oxygen, according to gestational age (GA). Cox proportional hazards and regression models were fitted to evaluate the trend in duration of respiratory support, survival and surfactant treatment over the study period. RESULTS: The percentages of infants who died or were weaned from respiratory support were presented graphically over time by GA. Advancing GA was associated with ordinally earlier weaning from respiratory support. Year over year, infants born at 23 weeks were initially and definitively weaned from endotracheal and all PPS earlier (HR 1.06, 95% CI 1.01 to 1.11, for all outcomes), while survival simultaneously increased (OR 1.11, 95% CI 1.03 to 1.18). Infants born at 26 and 27 weeks remained on non-invasive PPS longer (HR 0.97, 95% CI 0.95 to 0.98 and HR 0.97, 95% CI 0.95 to 0.99, respectively). Early surfactant treatment declined among infants born at 24-27 weeks GA. CONCLUSIONS: Infants at the borderline of viability have experienced improved survival and earlier weaning from all forms of PPS, while those born at 26 and 27 weeks are spending more time on PPS in recent years. GA-based estimates of the duration of respiratory support and survival may assist in counselling, benchmarking, quality improvement and resource planning.