
==== Front
Eur Arch Otorhinolaryngol
Eur Arch Otorhinolaryngol
European Archives of Oto-Rhino-Laryngology
0937-4477
1434-4726
Springer Berlin Heidelberg Berlin/Heidelberg

38743080
8728
10.1007/s00405-024-08728-4
Rhinology
Heated humidified high-flow nasal cannula: a new conservative approach for neonatal nasal stenosis
http://orcid.org/0009-0009-9435-374X
Havazelet Shany shany.havazelet@gmail.com

14
Stafler Patrick 24
Zarzur Ihab 2
Coreanu Tara 14
Hod Roy 34
Armoni-Domany Keren 45
Gilony Dror 34
1 https://ror.org/01vjtf564 grid.413156.4 0000 0004 0575 344X Department of Otolaryngology - Head and Neck Surgery, Rabin Medical Center, Petach Tikva, Israel
2 https://ror.org/01z3j3n30 grid.414231.1 0000 0004 0575 3167 Institute of Pediatric Pulmonology, Schneider Children’s Medical Center of Israel, Petach Tikva, Israel
3 https://ror.org/01z3j3n30 grid.414231.1 0000 0004 0575 3167 Department of Pediatric Otolaryngology, Schneider Children’s Medical Center of Israel, Petach Tikva, Israel
4 https://ror.org/04mhzgx49 grid.12136.37 0000 0004 1937 0546 Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
5 https://ror.org/04ayype77 grid.414317.4 0000 0004 0621 3939 Department of Pediatrics, Edith Wolfson Medical Center, Holon, Israel
14 5 2024
14 5 2024
2024
281 10 52615266
10 3 2024
6 5 2024
© The Author(s) 2024
2024
https://creativecommons.org/licenses/by/4.0/ Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
Purpose

The aim of this study is to evaluate the efficacy of heated humidified high flow nasal cannula (HFNC) therapy as a conservative treatment option for newborns suffering from nasal stenosis, a condition that often leads to respiratory distress and feeding difficulties. Given the increasing utilization of HFNC in various upper and lower respiratory tract indications, characterized by its flow-based mechanism and minimal mucosal damage, we seek to investigate its potential benefits in this specific patient population.

Methods

A retrospective chart review of newborns with congenital nasal stenosis treated with HFNC for respiratory distress or feeding difficulties in a pediatric tertiary center between 2014 and 2022. Data were collected for demographic characteristics, clinical presentation and ventilatory requirements, pre and post HFNC application.

Results

Six infants with nasal stenosis were included in the study cohort. Five were diagnosed with congenital pyriform aperture stenosis, three of whom had additional midnasal stenosis. One patient had nasal synechiae. Two patients had failed surgical treatment and all patients failed conservative treatment prior to HFNC treatment. Following HFNC use, improvement was noted in oxygen saturations, heart and respiratory rates, meal volumes and weight. None of the patients required any additional sinonasal surgical treatment. No complications were observed.

Conclusions

In this case series, we present the first documented use of HFNC treatment for nasal stenosis, showing favorable results. Further studies with a larger cohort, wider range of conditions and extended follow-up periods are needed to establish the risks and benefits of HFNC for neonatal nasal stenosis.

Keywords

Heated humidified high-flow nasal cannula (HFNC)
Nasal stenosis
Congenital pyriform aperture stenosis
Sinonasal surgical treatment
Pediatric respiratory management
Tel Aviv UniversityOpen access funding provided by Tel Aviv University.

issue-copyright-statement© Springer-Verlag GmbH Germany, part of Springer Nature 2024
==== Body
pmcIntroduction

Congenital nasal stenosis poses significant challenges for newborns, as their obligatory nasal breathing predisposes them to shortness of breath and feeding difficulties [1]. Furthermore, iatrogenic nasal stenosis can arise from repeated nasal trauma, including nasogastric tube insertions and repeated nasal suctioning, particularly in cases of premature infants in intensive care settings [2]. Severe stenosis may lead to extreme respiratory distress, feeding challenges, and failure to gain weight [3]. The primary approach to management is conservative, aiming to preserve sufficient airway patency. This involves the use of topical decongestants, saline irrigations, humidifiers, or nasal suction [4]. Severe cases may warrant continuous oxygen support or even require mechanical ventilation to alleviate hypoxia.

Despite initial attempts at conservative management, inadequate improvement may require resorting to a surgical intervention focused on expanding the nasal aperture. Nevertheless, surgical management has emerged as the definitive treatment modality in more than 80% of nasal stenosis cases [5]. Consequently, the pivotal role of the otolaryngologist in diagnosing and selecting the optimal surgical strategy for addressing nasal stenosis cannot be overstated.

Surgical interventions for congenital nasal stenosis are performed within a limited anatomical space. This may contribute to complications such as synechia, restenosis or injuries to the lacrimal duct and tooth buds [6]. Consequently, surgical management poses a considerable risk of long-term complications, warranting non-interventional alternatives whenever feasible.

Heated humidified high flow nasal cannula (HFNC) treatment has become a valuable tool in managing respiratory insufficiency in children, resulting from parenchymal or airway etiologies. This modality administers a humidified air-oxygen mixture through nasal prongs, ventilating both the upper and lower respiratory tracts, while minimizing damage to the mucous membranes [7].

HFNC demonstrated success in treating respiratory distress syndrome in preterm infants [8]. Further investigations have explored its potential in managing obstructive sleep apnea (OSA) in children, yielding favorable outcomes comparable to CPAP treatment [9, 10]. Initially used within the hospital setting, treatment at home is now supported for a variety of indications [11].

In the present study, we present a case series examining a novel application of HFNC in the context of conservative treatment for newborns with nasal stenosis. This innovative approach aims to improve respiratory function and alleviate feeding difficulties, offering a potential alternative to surgical interventions for this vulnerable patient population.

Methods

Study design and setting

This was a retrospective single center cohort study, examining demographic and clinical data of children aged 0–18 years with congenital nasal stenosis who were treated with HFNC for respiratory distress and/or failure to gain weight between the years 2014–2022 at Schneider Children's Medical Center of Israel, a tertiary pediatric center.

Included in the study were children diagnosed with congenital nasal stenosis, as confirmed by physical examination including Fiberoptic Rhinolaryngoscopy, who displayed persistent respiratory distress despite conservative measures. Computed tomography (CT) imaging complemented the diagnosis, aiding in cases where the scope exam could not be complete due to severe stenosis. Assessments of stenotic area were conducted in the axial view, with the image aligned parallel to the plane of the bony palate using multi-plane reconstruction techniques. Measurements of stenosis dimensions and locations, including mid-nasal, pyriform aperture, and choana, were performed according to the method outlined by Levi et al. [12].

Medical records were reviewed for demographic characteristics and clinical data prior and subsequent to HFNC use, focusing on respiratory and growth status. All oxygen saturation, respiratory and heart rate measurements recorded within 48 h pre and 48 h post commencing HFNC were collected and averaged. Patients’ feeding volumes per meal, averaged over 24 h periods prior to commencing HFNC and one month post start of treatment were recorded, as was weight, using the closest available measurements prior to and one month post start of treatment. Weight growth percentage was calculated using the WHO child and toddler growth chart [13]. Technical data on HFNC use were collected including fraction of inspired oxygen (FiO2), flow rate, temperature, and humidity.

Treatment protocol

Children identified as eligible for HFNC treatment were trialed on the Precision flow (Vapotherm) during an inpatient stay. They were monitored clinically and with a pulse oximeter to determine benefit in terms of respiratory distress and ability to feed. Blood gases were not measured routinely. Air flow was titrated as tolerated, usually aiming to achieve a flow rate of 2 L/kg/min. Once children were found to benefit from HFNC, a home device was ordered. A humidifier and flow generator device (myAirvo 2; Fisher & Paykel Healthcare) were used to deliver high flow via nasal cannulae. These were chosen according to nasal aperture and weight, to achieve optimal flow rate (Optiflow Junior S or M; Fisher & Paykel Healthcare). The nasal cannula maintained a temperature of 34°C and relative humidity of 100% at the nasal outlet as reported by the manufacturer.

Children were required to remain inpatients for at least one further night using the home device, to adapt the interface and ensure safety and effective ventilation. Parents were trained in the use of the device and underwent a resuscitation tutorial. Patients were prescribed a home pulse oximeter and, when required, suction device and oxygen concentrator. A home ventilation team was assembled, consisting of a technician and a physician, tasked with regular home visits, maintenance, and trouble shooting.

Statistical analysis

Statistical analyses were performed with SPSS software, version 25.0 (Armonk, NY: IBM Corp.). Continuous variables were described using median and range, categorical variables were described using percentage.

Results

Patient characteristics

The study cohort initially included seven children (six males and one female) with median gestational age of 39 weeks (range 25–40). Notably, one patient with VACTERL syndrome was diagnosed with congenital multi-level nasal stenosis through CT imaging. This patient commenced HFNC therapy at 21 weeks but struggled to adapt to the device, ultimately requiring a tracheostomy at a different medical facility less than a month after initiating HFNC treatment, where he continued follow-up care.

For the final cohort, congenital nasal stenosis was diagnosed at a median age of 3 weeks (Range 2–7). Most of these children had additional comorbidities resulting from developmental congenital anomalies, such as central line anomalies syndromes. The location of nasal stenosis varied among patients, encompassing pyriform aperture, mid-nasal, and multilevel stenosis. Median follow-up time was 14 months (Range 6–46). Demographic and clinical characteristics of the participants are provided in Table 1.Table 1 Patient characteristics

Patient #	Gestational age at birth (weeks)	Gender	Weight at birth (Kg)	Age at diagnosis (weeks)	Comorbidities	Feeding route	Type of stenosis	Additional nasal pathology	Treatment before HFNC	
1	39	Male	3.3	3	–	PO	CPAS	Septal deviation	Dethamycin nasal drops	
2	39	Male	2.8	3	Adrenal insufficiency, inner ear anomaly	PO	CPAS	Septal deviation	Dethamycin nasal drops	
3	38	Male	2.4	2	Hypoplastic heart	PEG	CPAS, midnasal	Septal deviation	Dethamycin nasal drops	
4	25	Male	1	7	BPD, retinopathy	PO	Synechia, choanal	–	ESS for adhesionlysis	
5	39	Male	3.9	2	–	PO	CPAS	–	Saline drops, oral steroids	
6	40	Female	3.4	4	Central line anomalies	PEG	CPAS, choanal	–	Surgical turbinate deviation and stenosis expansion	
CPAS: congenital pyriform aperture stenosis; BPD: bronchopulmonary dysplasia; ESS: Endoscopic sinus surge

Clinical presentation

All patients exhibited symptoms indicative of upper airway obstruction, leading to respiratory distress. In five of them, feeding difficulties were associated, with two requiring feeding through percutaneous endoscopic gastrostomy (PEG) to ensure sufficient intake.

Three patients underwent Computer tomography (CT) prior to initiating HFNC therapy, to reveal the level of the stenosis. All received conservative treatment including dethamycin nasal drops. One patient received saline nasal drops combined with oral steroids. Two patients underwent surgical procedures. The surgical interventions included turbinate deviation and stenosis expansion in one case, and lysis of adhesions in another. These treatments yielded insufficient improvement with subsequent implementation of HFNC therapy.

HFNC usage

The median initiation age for HFNC usage was recorded at 12.5 weeks, encompassing a wide range from 3 to 68 weeks. Mean age at initiation was 22 weeks (SD 23.7). This variability is mainly owing to one patient who was referred to our medical center following an unsuccessful prior surgical intervention elsewhere.

There was also notable heterogeneity with regards to the duration of HFNC utilization, spanning from a brief one-month period of usage to continuous application by 13 months of follow-up. The collective median duration of HFNC use amounted to 9 months (range 1–15). Whilst all patients used the device during sleep, four patients were reliant on it during the day as well. Instances of truncated use predominantly stemmed from difficulties attaining optimal fit of the cannula.

Individualized HFNC device configurations were tailored to patient attributes and demands. Further details about HFNC treatment are shown in Table 2.Table 2 HFNC Usage Summary

Patient #	Age at HFNC initiation (weeks)	HFNC flow (L/kg/min)	% Fractional inspired Oxygen	Type of use	Duration of myAirvo use (months)	
1	3	2	25	24/7	15	
2	3	2	30	Sleep	8	
3	38	2	21	24/7	13*	
4	20	0.5	24	Sleep	7	
5	5	2	21	Night ± day	12	
6	68	1	21	24/7	1	
*Continuous use, exceeding follow-up period

Treatment outcomes

Table 3 shows the impact of HFNC institution on a number of variables. Increased oxygen saturation, with or without oxygen supplementation, was observed in all individuals commenced on HFNC therapy. Furthermore, mean respiratory and heart rates tended to drop following institution of HFNC, indicating physiological benefit through reduced work of breathing.Table 3 Treatment outcomes

Patient #	Mean O2 Saturation (%)a	Mean RRa	Mean HRa	Feeding volume per meal (ml)b	Weight Growth Centilec	
	Pre-treatment (room air)	Post -treatment	Pre-treatment	Post-treatment	Pre-treatment	Post-treatment	Pre-treatment	Post-treatment	Pre-treatment (%)	1-month post-treatment (%)	
1	60	100d	50	N/A	180	138	60	90	0	41	
2	89	97d	60	N/A	180	140	90	120	9.7	26.1	
3	72	80	27	20	122	110	100	140	0	41	
4	N/A	N/A	N/A	55	N/A	N/A	120	180	40	60	
5	85	100	42	30	177	136	N/A	N/A	10	68.9	
6	82	98	N/A	32	130	122	N/A	145	0.1	1.8	
RR: respiratory rate; HR: heart rate

aMean of all measurements recorded 48 h pre and 48 h post commencing HFNC

bPatients’ feeding volumes per meal, averaged over 24-h periods prior to commencing HFNC and one month post start of treatment

cAccording to the WHO Child Toddler Growth Chart(11)

dO2 supplementation (see details in Table 2)

Notably, feeding routines were observed to improve in all four orally fed patients with increase intake volumes compared to those tolerated prior to the commencement of HFNC therapy. After one month of treatment, assessments of growth centiles showed improved weight gain in all individuals.

Discussion

The incidence of nasal stenosis, though infrequent, poses significant risks for serious medical complications, notably impacting respiration and feeding [3, 14]. To our knowledge this is the first study to suggest the use of heated humidified high-flow nasal cannula (HFNC) as a conservative solution for the treatment of nasal stenosis. Our preliminary study demonstrated encouraging results in improving respiratory and feeding difficulties.

Navigating the course of nasal stenosis management hinges fundamentally on the interplay of symptom severity and the patient's clinical trajectory. Mild cases can be effectively managed with conservative interventions like short-term intranasal corticosteroids or nasal decongestants, whereas moderate to severe obstruction scenarios necessitate surgical interventions [14]. In a study by Chakravarty et al. 84% of nasal stenosis cases necessitated surgical intervention after inadequate improvement despite medical management [5]. Hence, it is imperative for otolaryngologists to thoroughly explore conservative treatment options before considering surgical intervention as the next step.

Surgical approaches described in literature include removal of scar tissue, replacement with graft tissue, and post procedure stenting to reduce restenosis. Over time, however, these surgical techniques have seen limited transformative evolution, with only a handful of innovative alternatives proposed. For instance, Adams et al. suggested use of steel gauging earrings for dilation and stenting for the treatment of nasal stenosis [15]. Nasal stenosis presents intricate challenges for surgeons, mainly attributed to the inherent lack of cartilaginous structural support in the ala, a susceptibility to scar contracture, and an increased risk of restenosis [16].

Considering the transient nature of neonatal nasal stenosis, a conservative therapeutic approach is considered preferable as the primary line of management. In a noteworthy case series, Karplus et al. demonstrated the efficacy of conservative measures in managing nasal stenosis in five neonates. The approach encompassed nasal drops, frequent nasal suction, and temporary nasopharyngeal intubation, effectively ameliorating symptoms and negating the necessity for surgical intervention [17]. In addition, Kemal et al. described the use of a nasal trumpet as a non-invasive treatment method in congenital nasal stenosis, removed 1.5 months later with no further need of use [12, 18].

The most prevalent modalities used for noninvasive respiratory support are nasal continuous positive airway pressure (NCPAP) and heated humidified high-flow nasal cannula (HFNC). In cases of pediatric obstructive sleep apnea, both have demonstrated comparable therapeutic effect among children with obesity and medical complexities, yielding similar reductions in polysomnography quantified measures of OSA severity [9]. However, HFNC showed promise as an alternative for children with OSA who struggle with CPAP adherence, particularly in cases where CPAP usage is refused due to inadequately fitting masks or other practical constraints [19]. Furthermore, a meta-analysis conducted by Lou et al. highlighted the advantages of HFNC over NCPAP in terms of enhancing feeding tolerance [20].

Our therapeutic approach is founded on the understanding that nasal stenosis represents a transient condition that tends to improve as the patient goes through natural growth and development. Consequently, surgical interventions, which bear the potential for enduring lasting complications, are an unfavorable course of action. Employing HFNC support until the nasal stenosis resolves offers a comfortable and non-permanent solution, mostly enabling patients to maintain their regular daily activities.

It is imperative to acknowledge the inherent limitations of our study, primarily stemming from its small sample size and retrospective design. Furthermore, the lack of a formal definition or classification system for nasal stenosis introduces potential variability in diagnosis interpretation; although we utilized both clinical and imaging data to define the diagnosis, other studies may adopt different criteria, emphasizing the need for a standardized definition. Moreover, considering the retrospective nature of the study, obtaining objective measurements from case notes at the time of admission was not always feasible. Consequently, further studies, with a larger number of participants and a wider range of indications, are warranted to establish the utility of HFNC in the context of neonatal nasal stenosis accompanied by respiratory distress, as well as to evaluate the long-term effects of this novel therapeutic approach.

Conclusions

This case series underscores the potential of HFNC as a novel approach to conservatively manage respiratory distress from nasal stenosis, particularly in scenarios where conventional conservative or surgical strategies are deemed inadequate. The present study sets the stage for future research into the efficacy of HFNC within this specific patient population.

Funding

Open access funding provided by Tel Aviv University. An educational grant was received from Fisher & Paykel.

Declarations

Conflict of interest

The company did not participate in data collection, statistical analysis, or interpretation of the findings.

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Shany Havazelet and Patrick Stafler have contributed equally to this study.
==== Refs
References

1. Trabalon M Schaal B It takes a mouth to eat and a nose to breathe: abnormal oral respiration affects neonates’ oral competence and systemic adaptation Int J Pediatr 2012 2012 1 10 10.1155/2012/207605
Trabalon M, Schaal B (2012) It takes a mouth to eat and a nose to breathe: abnormal oral respiration affects neonates’ oral competence and systemic adaptation. Int J Pediatr 2012:1–10. 10.1155/2012/207605
2. Smith LP Roy S Treatment strategy for iatrogenic nasal vestibular stenosis in young children Int J Pediatr Otorhinolaryngol 2006 70 8 1369 1373 10.1016/J.IJPORL.2006.01.015 16564097
Smith LP, Roy S (2006) Treatment strategy for iatrogenic nasal vestibular stenosis in young children. Int J Pediatr Otorhinolaryngol 70(8):1369–1373. 10.1016/J.IJPORL.2006.01.01516564097
3. Sohal M Schoem SR Disorders of the neonatal nasal cavity: fundamentals for practice Semin Fetal Neonatal Med 2016 21 4 263 269 10.1016/J.SINY.2016.03.007 27036653
Sohal M, Schoem SR (2016) Disorders of the neonatal nasal cavity: fundamentals for practice. Semin Fetal Neonatal Med 21(4):263–269. 10.1016/J.SINY.2016.03.00727036653
4. Galluzzi F Garavello W Dalfino G Castelnuovo P Turri-Zanoni M Congenital bony nasal cavity stenosis: a review of current trends in diagnosis and treatment Int J Pediatr Otorhinolaryngol 2021 144 110670 10.1016/J.IJPORL.2021.110670 33706014
Galluzzi F, Garavello W, Dalfino G, Castelnuovo P, Turri-Zanoni M (2021) Congenital bony nasal cavity stenosis: a review of current trends in diagnosis and treatment. Int J Pediatr Otorhinolaryngol 144:110670. 10.1016/J.IJPORL.2021.11067033706014
5. Chakravarty PD Sim F Slim MAM Patel N Wynne DM Clement WA Congenital nasal pyriform aperture stenosis; our experience of 34 cases Int J Pediatr Otorhinolaryngol 2023 166 111491 10.1016/j.ijporl.2023.111491 36870158
Chakravarty PD, Sim F, Slim MAM, Patel N, Wynne DM, Clement WA (2023) Congenital nasal pyriform aperture stenosis; our experience of 34 cases. Int J Pediatr Otorhinolaryngol 166:111491. 10.1016/j.ijporl.2023.11149136870158
6. Collares MVM Tovo AHS Duarte DW Schweiger C Fraga MM Novel treatment of neonates with congenital nasal pyriform aperture stenosis Laryngoscope 2015 125 12 2816 2819 10.1002/LARY.25198 25684725
Collares MVM, Tovo AHS, Duarte DW, Schweiger C, Fraga MM (2015) Novel treatment of neonates with congenital nasal pyriform aperture stenosis. Laryngoscope 125(12):2816–2819. 10.1002/LARY.2519825684725
7. Nolasco S Manti S Leonardi S Vancheri C Spicuzza L High-flow nasal cannula oxygen therapy: physiological mechanisms and clinical applications in children Front Med 2022 9 920549 10.3389/fmed.2022.920549
Nolasco S, Manti S, Leonardi S, Vancheri C, Spicuzza L (2022) High-flow nasal cannula oxygen therapy: physiological mechanisms and clinical applications in children. Front Med 9:920549. 10.3389/fmed.2022.920549
8. Yoder BA Stoddard RA Li M King J Dirnberger DR Abbasi S Heated, humidified high-flow nasal cannula versus nasal CPAP for respiratory support in neonates Pediatrics 2013 10.1542/peds.2012-2742 23650301
Yoder BA, Stoddard RA, Li M, King J, Dirnberger DR, Abbasi S (2013) Heated, humidified high-flow nasal cannula versus nasal CPAP for respiratory support in neonates. Pediatrics. 10.1542/peds.2012-274223650301
9. Fishman H Heated humidified high flow nasal cannula therapy in children with obstructive sleep apnea: a randomized cross-over trial Sleep Med 2023 107 81 88 10.1016/J.SLEEP.2023.04.017 37148831
Fishman H et al (2023) Heated humidified high flow nasal cannula therapy in children with obstructive sleep apnea: a randomized cross-over trial. Sleep Med 107:81–88. 10.1016/J.SLEEP.2023.04.01737148831
10. Du F Gu YH He YC Deng WF Liu ZZ High-flow nasal cannula therapy for pediatric obstructive sleep apnea: a systematic review and meta-analysis Eur Rev Med Pharmacol Sci 2022 10.26355/eurrev_202207_29179 36524495
Du F, Gu YH, He YC, Deng WF, Liu ZZ (2022) High-flow nasal cannula therapy for pediatric obstructive sleep apnea: a systematic review and meta-analysis. Eur Rev Med Pharmacol Sci. 10.26355/eurrev_202207_2917936524495
11. Ehrlich S High flow nasal cannula therapy in the pediatric home setting Pediatr Pulmonol 2023 58 3 941 948 10.1002/ppul.26282 36564183
Ehrlich S et al (2023) High flow nasal cannula therapy in the pediatric home setting. Pediatr Pulmonol 58(3):941–948. 10.1002/ppul.2628236564183
12 Levi L Kornreich L Hilly O Raveh E Gilony D Clinical and imaging evaluation of congenital midnasal stenosis Int J Pediatr Otorhinolaryngol 2020 10.1016/J.IJPORL.2020.109918 33434698
Levi L, Kornreich L, Hilly O, Raveh E, Gilony D (2020) Clinical and imaging evaluation of congenital midnasal stenosis. Int J Pediatr Otorhinolaryngol. 10.1016/J.IJPORL.2020.10991833434698
13. De Onis M WHO Child Growth Standards based on length/height, weight and age Acta Paediatr Int J Paediatr 2006 95 Suppl 450 10.1080/08035320500495548
De Onis M (2006) WHO Child Growth Standards based on length/height, weight and age. Acta Paediatr Int J Paediatr 95(Suppl):450. 10.1080/08035320500495548
14 Rao A Godehal SM Patil AR Mallarajapatna G Nandikoor S Hariharan M Congenital nasal pyriform aperture stenosis: a rare cause of neonatal nasal airway obstruction BJR Case Rep 2015 1 1 20150006 10.1259/bjrcr.20150006 30363181
Rao A, Godehal SM, Patil AR, Mallarajapatna G, Nandikoor S, Hariharan M (2015) Congenital nasal pyriform aperture stenosis: a rare cause of neonatal nasal airway obstruction. BJR Case Rep 1(1):20150006. 10.1259/bjrcr.2015000630363181
15. Le J Adams NS Girotto JA Polley JW Mann RJ A novel treatment of nasal stenosis using steel gauging earrings Cleft Palate-Craniofacial J 2018 55 3 462 465 10.1177/1055665617734992/ASSET/IMAGES/LARGE/10.1177_1055665617734992-FIG4.JPEG
Le J, Adams NS, Girotto JA, Polley JW, Mann RJ (2018) A novel treatment of nasal stenosis using steel gauging earrings. Cleft Palate-Craniofacial J 55(3):462–465. 10.1177/1055665617734992/ASSET/IMAGES/LARGE/10.1177_1055665617734992-FIG4.JPEG
16. Daines SM Hamilton GS Mobley SR A graded approach to repairing the stenotic nasal vestibule Arch Facial Plast Surg 2010 12 5 332 338 10.1001/archfacial.2010.58 20855776
Daines SM, Hamilton GS, Mobley SR (2010) A graded approach to repairing the stenotic nasal vestibule. Arch Facial Plast Surg 12(5):332–338. 10.1001/archfacial.2010.5820855776
17. Leiberman A Carmi R Bar-Ziv Y Karplus M Congenital nasal stenosis in newborn infants J Pediatr 1992 120 1 124 127 10.1016/S0022-3476(05)80615-8 1731008
Leiberman A, Carmi R, Bar-Ziv Y, Karplus M (1992) Congenital nasal stenosis in newborn infants. J Pediatr 120(1):124–127. 10.1016/S0022-3476(05)80615-81731008
18 Kemal Ö Atmaca S Bel-Çeçen A Düzgün B Aygün HC The use of nasal trumpet as a non-invasive treatment method in congenital nasal stenosis Turk J Pediatr 2017 10.24953/turkjped.2017.02.017 29276878
Kemal Ö, Atmaca S, Bel-Çeçen A, Düzgün B, Aygün HC (2017) The use of nasal trumpet as a non-invasive treatment method in congenital nasal stenosis. Turk J Pediatr. 10.24953/turkjped.2017.02.01729276878
19. Singh S Ananthan A Nanavati R Post-INSURE administration of heated humidified high-flow therapy versus nasal continuous positive airway pressure in preterm infants more than 28 weeks gestation with respiratory distress syndrome: a randomized non-inferiority trial J Trop Pediatr 2022 10.1093/TROPEJ/FMAC062 36708041
Singh S, Ananthan A, Nanavati R (2022) Post-INSURE administration of heated humidified high-flow therapy versus nasal continuous positive airway pressure in preterm infants more than 28 weeks gestation with respiratory distress syndrome: a randomized non-inferiority trial. J Trop Pediatr. 10.1093/TROPEJ/FMAC06236708041
20. Luo J Duke T Chisti MJ Kepreotes E Kalinowski V Li J Efficacy of High-flow nasal cannula vs standard oxygen therapy or nasal continuous positive airway pressure in children with respiratory distress: a meta-analysis J Pediatr 2019 215 199 208.e8 10.1016/j.jpeds.2019.07.059 31570155
Luo J, Duke T, Chisti MJ, Kepreotes E, Kalinowski V, Li J (2019) Efficacy of High-flow nasal cannula vs standard oxygen therapy or nasal continuous positive airway pressure in children with respiratory distress: a meta-analysis. J Pediatr 215:199-208.e8. 10.1016/j.jpeds.2019.07.05931570155
