- Email: [email protected]
A novel technique for unilateral supraglottoplasty
International Journal of Pediatric Otorhinolaryngology 104 (2018) 150–154
Contents lists available at ScienceDirect
International Journal of Pediatric Otorhinolaryngology journal homepage: www.elsevier.com/locate/ijporl
A novel technique for unilateral supraglottoplasty☆
T
∗
Harry H. Ching , Alycia G. Spinner, Nathaniel H. Reeve, T.J. O-Lee Department of Otolaryngology - Head and Neck Surgery, University of Nevada Las Vegas School of Medicine, 1701 W. Charleston Blvd., Suite #490, Las Vegas, NV 89102, USA
A R T I C L E I N F O
A B S T R A C T
Keywords: Supraglottoplasty Congenital laryngomalacia Pediatric airway
Objectives: Traditional supraglottoplasty for pediatric laryngomalacia is most commonly conducted with either CO2 laser or cold steel instruments. While the procedure enjoys high success rates, serious complications such as excessive bleeding, supraglottic stenosis and aspiration can occur. Unilateral coblation supraglottoplasty may reduce this risk, but data on respiratory and swallowing outcomes are lacking. This study reports our experiences with unilateral coblation supraglottoplasty. Methods: Pediatric patients with severe congenital laryngomalacia who underwent unilateral supraglottoplasty at a single institution from 2013 to 2016 were retrospectively reviewed. Bipolar radiofrequency ablation (Coblation) was utilized with partial arytenoidectomy, aryepiglottoplasty, and advancement of mucosal flaps. Outcome measures included apnea-hypopnea index (AHI), weight-by-age percentile, and decannulation rate. Results: Twelve patients were included with an average age of 13.1 months (range 2–28 months). In patients without tracheostomy, 88% had complete resolution of respiratory symptoms, while the remainder had significant improvement. In patients without gastrostomy tubes, there was an average increase in weight-age percentile of 6.1, 7.8, and 15.3 points at 1, 3, and 6 months postoperatively, respectively. Three patients had complete polysomnography data with a mean preoperative AHI of 19.3 and postoperative AHI of 4.0. Three of four patients with tracheostomy have been decannulated at a mean follow-up of 1.5 years. There were no early or late postoperative complications and no revision supraglottoplasty. Conclusion: Unilateral supraglottoplasty with bipolar radiofrequency ablation can improve respiratory symptoms and decrease OSA severity in severe congenital laryngomalacia. This technique is safe and can lead to substantial improvement in AHI in patients with OSA.
1. Introduction Laryngomalacia is the most common congenital laryngeal anomaly and a common cause of stridor in infants [1]. The characteristic finding is varying degrees of airway obstruction caused by collapse of redundant supraglottic tissue. Patients generally present with inspiratory stridor shortly after birth which worsens in the first several months of life. In the majority of patients, laryngomalacia is self-limited and resolves with empiric medical treatment for gastroesophageal reflux disease (GERD). In up to 20% of patients with laryngomalacia, surgical management is needed due to a severe presentation or worsening of symptoms despite conservative treatment [2]. These patients may have cyanotic episodes, severe OSA, dysphagia, and failure to thrive. Supraglottoplasty (SGP) is currently the most common surgical treatment for severe laryngomalacia [3]. Using a CO2 laser or cold instruments, bilateral arytenoids are trimmed and the aryepiglottic
folds are divided to increase the supraglottic airway. Although rare, supraglottic stenosis and aspiration can occur following bilateral SGP [3]. Supraglotic stenosis has been reported in up to 4% of patients and can lead to multiple revision airway surgeries or tracheostomy-dependence [4]. Subsequently, unilateral supraglottoplasty has been increasingly investigated to minimize the risk of supraglottic stenosis. Bipolar radiofrequency ablation (RFA) devices have become increasingly popular for laryngeal applications, such as in respiratory papillomatosis. These devices reduce airway fire risk and heat induced thermal injury compared to the CO2 laser. They also allow simultaneous endoscope use in the off-hand and can enhance visualization. Two characteristics of our technique for unilateral SGP have not been previously described in detail: 1) the use of a bipolar radiofrequency ablation device and 2) the advancement and suturing of mucosal flaps to increase the laryngeal airway and reduce the demucosalized surface area. Data on respiratory and swallowing outcomes in unilateral SGP have been limited to a few case series [2,5,6]. This study aims to
☆ ∗
Presented at the 2016 AAO-HNS Annual Meeting, San Diego, CA USA on September 18, 2016. Corresponding author. E-mail addresses: [email protected] (H.H. Ching), [email protected] (A.G. Spinner), [email protected] (N.H. Reeve), [email protected] (T.J. O-Lee).
https://doi.org/10.1016/j.ijporl.2017.11.003 Received 12 September 2017; Received in revised form 2 November 2017; Accepted 3 November 2017 Available online 06 November 2017 0165-5876/ © 2017 Elsevier B.V. All rights reserved.
International Journal of Pediatric Otorhinolaryngology 104 (2018) 150–154
H.H. Ching et al.
describe our experience with the use of a bipolar RFA device for supraglottoplasty and to evaluate the complications and efficacy of this technique.
area. The airway is examined for patency under spontaneous ventilation. The patient is generally extubated prior to returning to the postanesthesia care unit.
2. Materials and methods
2.3. Definitions
2.1. Patient identification and management
Weight by age percentile was calculated using the 2006 WHO Growth Standard Charts for patients aged 0–24 months of age and the 2000 CDC Growth Charts for 2–20 years of age. When applicable, weight by age percentile for preterm patients was corrected and calculated using the 2013 Fenton Growth Charts. Prolonged intubation was defined as a period greater than 2 weeks. Severe laryngomalacia on flexible laryngoscopy was defined as a narrowed laryngeal airway with the following features: 1) inward collapse of mucosa of the arytenoids and aryepiglottic folds, 2) collapse of the epiglottis inwards during inspiration, and 3) short aryepiglottic folds. Moderate laryngomalacia was defined as a narrowed laryngeal airway with at least 1 of the signs of laryngomalacia on laryngoscopy. The pediatric OSA grading system proposed by Katz et al. [8] was used as follows: 1) severe OSA: OAHI ≥ 10 or an SpO2 nadir ≤ 75%, 2) moderate OSA: OAHI between 5 and 9 or SpO2 nadir between 76% and 85%, 3) mild OSA: OAHI between 1 and 5. Potential complications included any intervention requiring return to the operating room in the perioperative period, worsening aspiration, severe respiratory events requiring re-intubation or noninvasive ventilation, postoperative hemorrhage, and supraglottic stenosis.
This is a retrospective case series of pediatric patients with congenital laryngomalacia who underwent unilateral supraglottoplasty from 2014 to 2016. Prior to 2014, supraglottoplasty was performed with CO2 laser in a bilateral fashion at our institution. Pediatric patients who underwent unilateral supraglottoplasty were identified using case logs. Indications for supraglottoplasty in this cohort included: 1) evidence of laryngomalacia with airway compromise on flexible or direct laryngoscopy and 2) symptoms of moderate to severe laryngomalacia such as recurrent stridor, OSA, dysphagia with failure to thrive, and recurrent episodes of apnea or cyanosis. Exclusion criteria included a history of open or endoscopic laryngeal surgery prior to supraglottoplasty. This study was approved by the University of Nevada School of Medicine Institutional Review Board. Preoperative workup included a full history and physical examination with flexible laryngoscopy. Patients with endoscopic findings of laryngomalacia were treated with a trial of acid-suppression therapy and monitored for worsening of symptoms. After publication of the 2016 Laryngomalacia Consensus Recommendations by the International Pediatric ORL Group (IPOG), patients were managed according to acid suppression “step-up” guidelines [7]. Whenever possible, preoperative and postoperative polysomnography (PSG) was obtained. Postoperatively, patients without tracheostomy were routinely admitted to the pediatric intensive care unit and were often discharged the next day. Patients with tracheostomy and without severe comorbidities were discharged the same day. Oral diet was started immediately after surgery and pain was generally controlled with a combination of ibuprofen and acetaminophen. All patients were routinely given antibiotics, acid suppression, and one week of systemic steroids. Patients were maintained on or weaned from acid suppression therapy according to the IPOG post-surgical treatment algorithm [7]. Flexible laryngoscopy was repeated at regular intervals to assess for residual laryngomalacia.
2.4. Data and statistical analysis Data collected from chart review included demographic information, preoperative symptoms, comorbidities, and patient weight at each clinic visit. Operative data included operative findings, procedural details, and operative time. Inpatient data included medication use, oxygen requirements, length of ICU and hospital stay. Postoperative data included hospital readmissions for respiratory reasons, tracheostomy weaning, and additional airway procedures. Primary outcome measures included resolution of symptoms, tracheostomy decannulation, change in OAHI, change in swallowing and weight percentile, revision supraglottoplasty, and additional airway procedures. Statistical analysis was carried out using SPSS Statistics 20 (IBM Corp, Armonk, NY).
2.2. Surgical technique 3. Results All surgical procedures were performed by the senior author (T.J.O.). General anesthesia was induced with gas anesthetic via mask. Direct laryngoscopy was performed using an appropriate-sized Parsons laryngoscope and the patient was suspended on the Mayo stand. With the patient spontaneously ventilating, a complete evaluation of the airway was performed to rule out synchronous airway lesions. Because of the diminished fire risk with bipolar radiofrequency, performing supraglottoplasty with an endotracheal tube in place is a viable alternative to traditional general anesthesia under spontaneous ventilation. The bipolar radiofrequency ablation device used in this study was the COBLATION Microlaryngeal Wand (Smith & Nephew, London, UK). A zero-degree Hopkins rod with high magnification is used in the off-hand for visualization. Unilateral supraglottoplasty was generally carried out on the right side if the arytenoid cartilages and mucosa were symmetric. See Fig. 1. The aryepiglottic fold is routinely divided first. The mucosa overlying the arytenoid cartilage is ablated until the arytenoid cartilages are exposed. A small amount of arytenoid cartilage is ablated while preserving medial and lateral mucosal flaps around the arytenoid (see Fig. 1B). The mucosal flaps are then approximated using one or two 4-0 Vicryl sutures which are tied with an endoscopic knot pusher (see Fig. 1C). The Vicryl sutures serve two purposes: 1) lateralization of the medial mucosal flap to maximize the laryngeal airway and 2) facilitation of postoperative healing by reducing the demucosalized surface
A total of 15 patients underwent unilateral supraglottoplasty in the study period, with three patients excluded due to prior or additional endoscopic or open laryngoplasty. A total of 12 patients were included in the final analysis, with a mean age of 13.1 months. The majority of patients (67%) were full term, with only two patients extremely preterm (< 28 weeks). The most common comorbidity was neurologic (42%) which included agenesis of the corpus callosum, traumatic brain injury, cerebral palsy, and lissencephaly. Cardiac (25%) and pulmonary (25%) comorbidities included pulmonary hypertension, recurrent pneumonia, arrhythmia, and patent foramen ovale. Subjective dysphagia and swallowing difficulties were a common presenting symptom, found in 75% of patients, with 42% of patients having a gastrostomy tube preoperatively. Synchronous airway lesions were found in two patients, including one patient with tracheomalacia and one with subglottic stenosis (Cotton-Meyer Grade 3). See Table 1. Supraglottoplasty was right-sided in all patients and included division of the right A-E fold and partial arytenoidectomy with approximation of mucosal flaps. The total procedure duration was a mean of 40.1 min. All three patients with an existing tracheostomy were discharged the same day. Of the nine patients without a prior tracheostomy, eight were observed overnight in the pediatric ICU and discharged the next day. The ninth patient had an extended stay of four 151
International Journal of Pediatric Otorhinolaryngology 104 (2018) 150–154
H.H. Ching et al.
Fig. 1. Severe laryngomalacia in an 8 week old female. A: Pre-operative larynx. B: Mildly improved laryngeal airway after division of the right aryepiglottic fold and partial arytenoidectomy. C: Significantly improved laryngeal airway after approximating the mucosal edges with a single vicryl suture.
Table 1 Preoperative clinical characteristics.
Table 2 Operative and postoperative characteristics.
Characteristic
Never Trach Dependent
Trach Dependent
Decannulated
Overall
Characteristic
Pre-op Tracheostomy
No Tracheostomy
Overall
Total Patients Mean Age (m)
8 11.6
1 20.5
3 14.5
Number of Patients Operative Procedure Right-sided supraglottoplasty A-E fold Partial arytenoidectomy Operative time (min)
3
9
12
3 (100%)
9 (100%)
12 (100%)
3 (100%) 3 (100%) 43.5
9 (100%) 9 (100%) 39.3
Admitted postoperatively Supplemental Oxygen Requirement ICU Length of Stay (days)
0 0
9 (100%) 3 (33%)
12 (100%) 12 (100%) 40.1 (range 20–108) 9 (75%) 3 (25%)
0
1.4 (range 1–4)
Total Hospital Stay (days)
0
1.7 (range 1–4)
Hours until PO intakea Additional airway intervention prior to discharge
2.0 –
5.6 0
Female 3 Gestational Age Full Term 5 32 - < 37 weeks 2 28 - < 32 weeks 0 < 28 weeks 1 Comorbidities Neurologic 3 Cardiac 2 Pulmonary 1 Syndromic 0 H/o prolonged 1 Intubation Synchronous 2 Airway Lesion Laryngomalacia Severity Moderate 2 Severe 6 Dysphagia 5 G-tube 2 dependence Weight-age percentile 2 to < 5 1 <2 2
0
1
12 13.1 (range 2–28.3) 4 (33%)
1 0 0 0
2 0 0 1
8 (67%) 2 (17%) 0 2 (17%)
1 0 1 0 1
1 1 1 0 0
5 3 3 0 2
0
0
2 (17%)
0 1 1 1
0 3 3 2
2 (17%) 10 (83%) 9 (75%) 5 (42%)
0 0
1 0
2 (17%) 2 (17%)
(42%) (25%) (25%) (17%)
1.0 (range 0–4) 1.2 (range 0–4) 5.2 0
Values are means unless otherwise specified. a Patients without G-tube. Table 3 Respiratory outcomes.
Values indicate number of patients unless otherwise specified.
days due to limited PO intake. The patients began PO intake an average of 5.6 h after surgery. Only three patients required supplemental oxygen during the postoperative hospital stay. There were no complications in the immediate postoperative period. No patients required reintubation, non-invasive ventilation, or racemic epinephrine. See Table 2. Of the patients without a gastrostomy tube, two patients met criteria for failure-to-thrive (FTT) preoperatively. These patients had an increase in weight-by-age percentile (WAP) of 1 and 16.3 points at 3 month follow-up. Overall, the eight patients without gastrostomy tubes had an average increase in WAP of 6.1, 7.8, and 15.3 points at 1, 3, and 6 months postoperatively, respectively. There were 8 patients in the cohort who never had a tracheostomy, and seven of those had complete resolution of stridor and choking symptoms by 3 months postoperatively. The other patient had subjective improvement with a reported decreased frequency and severity of stridor. Three patients had both preoperative and postoperative PSG, and one patient had only postoperative PSG. The mean preoperative and postoperative OAHI was 19.3 and 4.0, respectively. There was a mean decrease in OAHI of 14.9 points. Of the patients with postoperative PSG, one patient had completely resolved OSA with
Characteristic
Patients
Patients Never Requiring Tracheostomy Symptomatic Improvement No Improvement Significant Improvement Complete Resolution Patients with postoperative PSG Mean Change in AHI Mean Postoperative AHI
8 0 1 7 4 - 14.9 4.0
Patients with preop tracheostomy Postoperative tracheostomy Decannulated
3 1 3
Values are numbers of patients unless otherwise specified.
OAHI < 1 and two patients had mild OSA with OAHI < 5. The fourth patient had a postoperative OAHI of 11, which was improved from the preoperative OAHI of 26. See Table 3. Three patients had a tracheostomy preoperatively, and one patient underwent tracheotomy 6 weeks after supraglottoplasty due to prolonged ventilator dependence secondary to pneumonia. The patient who underwent postoperative tracheotomy had drastic improvement in stridor and slow feeding in the postoperative weeks leading up to his hospitalization for pneumonia. He was eventually decannulated 4 months later. Of the three patients with tracheostomy prior to supraglottoplasty, two were successfully decannulated at 3 and 24 months 152
International Journal of Pediatric Otorhinolaryngology 104 (2018) 150–154
H.H. Ching et al.
Published series of unilateral supraglottoplasty have reported that 15–40% of patients will require a second stage or contralateral supraglottoplasty [2,5,6]. On postoperative laryngoscopy, no patients in this series had signs of significant residual laryngomalacia requiring revision supraglottoplasty. One possibility is that the lateralization of mucosal flaps of the arytenoid which may improve the supraglottic airway. Additionally, authors of other studies may have different indications for a staged contralateral supraglottoplasty. Bilateral supraglottoplasty may be associated with an up to 10% risk of significant complications such as postoperative edema with obstruction, worsening dysphagia, and supraglottic stenosis [3,4,14,15]. Supraglottic stenosis has been reported to occur in up to 4% of cases of bilateral supraglottoplasty [4], and although it is a rare complication, it can lead to multiple revision procedures or long-term tracheostomy dependence. Unilateral supraglottoplasty theoretically minimizes the risk of supraglottic stenosis by avoiding the proximity of two demucosalized arytenoid surfaces in contact during healing, which may prevent scar and adhesion formation. Our technique of suturing the mucosa may further reduce the demucosalized surface area and risk of scar formation. Indeed, to the best of our knowledge, there is not a reported case of supraglottic stenosis after the unilateral procedure in the current literature, including this series [2,5,6]. Walner et al. proposed a staged strategy of unilateral supraglottoplasty followed by contralateral supraglottoplasty several months later if symptoms persisted, which also theoretically avoids supraglottic stenosis with the potential benefit of the bilateral procedure [2]. This is the first case series describing outcomes of supraglottoplasty using a bipolar radiofrequency ablation device. In a survey of 101 otolaryngologists regarding supraglottoplasty practice patterns, cold steel was the most popular surgical technique, being used by 73% of respondents, followed by laser with 14% [16]. One major advantage of the low temperature RFA devices is the lack of airway fire risk, and therefore the entire procedure can be performed with a standard endotracheal tube in place. It also has the advantage over the CO2 laser of providing tactile feedback during ablation, to accurately determine depth towards the arytenoid cartilages. Bipolar RFA devices are excellent at achieving hemostasis while simultaneously ablating tissue, which is one advantage over the cold steel technique. Limitations of this study include those associated with retrospective case series. Certain subsets of data were extremely limited, such as PSG data because it was not routinely obtained for every patient in the series preoperatively. Swallowing outcomes were not measured objectively and therefore had to be indirectly inferred from weight percentile values. This is also a relatively small series, which limits comparison of outcomes to other studies of supraglottoplasty.
postoperatively. The patient requiring 24 months for decannulation also had Grade 3 subglottic stenosis requiring three dilations prior to supraglottoplasty, and at the time of decannulation, his subglottic stenosis was found to have improved to Grade 2. One patient remains tracheostomy dependent at 2 year follow-up and is progressing towards decannulation. Of note, this patient has severe neurologic deficits due to past traumatic brain injury. No patients have required revision supraglottoplasty or additional major airway procedures after unilateral supraglottoplasty, other than tracheotomy. 4. Discussion In this case series, pediatric patients with severe congenital laryngomalacia were treated with unilateral supraglottoplasty using a technique with two novel characteristics. These characteristics are: 1) the use of a bipolar RFA device and 2) vicryl sutures to increase the laryngeal airway by lateralizing the arytenoid mucosa and reducing the demucosalized surface area. Patients had moderate to complete improvement in respiratory symptoms, and there were no significant complications. In 1990, Katin and Tucker were the first to describe the potential efficacy of unilateral SGP [9]. Kelly and Gray [5] were the first to analyze outcomes for a series of patients who underwent unilateral CO2 laser supraglottoplasty for severe laryngomalacia. There were no major complications and a success rate of 94% with 3 of 18 patients requiring a subsequent contralateral SGP. Reddy et al. reported a series of unilateral SGP in 47 patients with a success rate of 96% and a contralateral procedure required in 15% of patients [6]. Complications included new postoperative aspiration in 8.5% of patients but no supraglottic stenosis. Walner et al. reviewed 15 patients who underwent staged unilateral SGP and found 100% had resolution respiratory symptoms by the second stage, with 40% of patients requiring the second stage or contralateral SGP. Of note, patients with neurologic comorbidities were excluded in that study. In the current study, 11 of 12 patients achieved decannulation or moderate to complete resolution of respiratory symptoms, while the remaining patient is progressing towards decannulation. Of the patients without tracheostomy, 88% achieved complete resolution of symptoms while the remainder had significant improvement. Marcus et al. in 1990 were among the earliest to report improvement in PSG parameters following SGP in four of six patients [10]. Zafereo reported a significant improvement in PSG parameters for 10 patients with congenital laryngomalacia who underwent bilateral SGP and found a mean improvement in OAHI from 12.2 to 4.2 [11]. More recently, there are a growing number of studies of SGP for OSA due to sleep-dependent laryngomalacia which can present in older pediatric patients. A meta-analysis of SGP for OSA in laryngomalacia by Lee et al. found a mean AHI improvement from 14.0 to 3.3 for sleep-dependent laryngomalacia and 20.4 to 4.0 for congenital laryngomalacia [12]. Patients in this study with complete PSG data showed a mean improvement in OAHI of 14.9 points, with all three patients having resolved or mild OSA postoperatively. Although the limited number of patients in this study with complete PSG data prevents a comparison to published OSA data in bilateral SGP, unilateral SGP may be able to treat OSA associated with severe congenital laryngomalacia. The incidence of tracheostomy-dependence for patients undergoing bilateral supraglottoplasty has been reported to be 3–14% when including patients with severe comorbidities [3,13]. Studies of unilateral supraglottoplasty have had 0–13% of patients requiring tracheotomy [2,5,6]. In the current literature, there does not appear to be a major difference in the incidence of tracheostomy-dependence between unilateral and bilateral supraglottoplasty, but further studies are needed. Risk factors for tracheotomy in these patients include synchronous airway lesions and severe neurologic comorbidity [2,13]. In this series, one patient had to undergo tracheotomy 6 weeks postoperatively for prolonged intubation due to pneumonia.
4.1. Conclusion Unilateral supraglottoplasty with bipolar radiofrequency ablation can improve respiratory symptoms and OSA severity in severe congenital laryngomalacia. This technique is safe and can lead to substantial improvement in AHI in patients with OSA. Conflicts of interest None. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Acknowledgements None. 153
International Journal of Pediatric Otorhinolaryngology 104 (2018) 150–154
H.H. Ching et al.
References [9]
[1] M.C. Thorne, S.L. Garetz, Laryngomalacia: review and summary of current clinical practice in 2015, Paediatr. Respir. Rev. 17 (2016) 3–8. [2] D.L. Walner, D.B. Neumann, K.K. Hamming, R.P. Miller, Supraglottoplasty in infants: a staged approach, Ann. Otol. Rhinol. Laryngol. 124 (2015) 803–807. [3] G.T. Richter, D.M. Thompson, The surgical management of laryngomalacia, Otolaryngol. Clin. North Am. 41 (2008) 837–864. [4] F. Denoyelle, M. Mondain, N. Gresillon, G. Roger, F. Chaudre, E.N. Garabedian, Failures and complications of supraglottoplasty in children, Arch. Otolaryngol. Head. Neck Surg. 129 (2003) 1077–1080 discussion 1080. [5] S.M. Kelly, S.D. Gray, Unilateral endoscopic supraglottoplasty for severe laryngomalacia, Arch. Otolaryngol. Head. Neck Surg. 121 (1995) 1351–1354. [6] D.K. Reddy, B.H. Matt, Unilateral vs. bilateral supraglottoplasty for severe laryngomalacia in children, Arch. Otolaryngol. Head. Neck Surg. 127 (2001) 694–699. [7] J. Carter, R. Rahbar, M. Brigger, K. Chan, A. Cheng, S.J. Daniel, A. De Alarcon, N. Garabedian, C. Hart, C. Hartnick, I. Jacobs, B. Liming, R. Nicollas, S. Pransky, G. Richter, J. Russell, M.J. Rutter, A. Schilder, R.J.H. Smith, J. Strychowsky, R. Ward, K. Watters, M. Wyatt, G. Zalzal, K. Zur, D. Thompson, International Pediatric ORL Group (IPOG) laryngomalacia consensus recommendations, Int. J. Pediatr. Otorhinolaryngol. 86 (2016) 256–261. [8] E.S. Katz, M.G. Greene, K.A. Carson, P. Galster, G.M. Loughlin, J. Carroll,
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C.L. Marcus, Night-to-night variability of polysomnography in children with suspected obstructive sleep apnea, J. Pediatr. 140 (2002) 589–594. L.I. Katin, J.A. Tucker, Laser supraarytenoidectomy for laryngomalacia with apnea, Trans. Pa. Acad. Ophthalmol. Otolaryngol. 42 (1990) 985–988. C.L. Marcus, D.M. Crockett, S.L. Ward, Evaluation of epiglottoplasty as treatment for severe laryngomalacia, J. Pediatr. 117 (1990) 706–710. M.E. Zafereo, R.J. Taylor, K.D. Pereira, Supraglottoplasty for laryngomalacia with obstructive sleep apnea, Laryngoscope 118 (2008) 1873–1877. C.F. Lee, C.H. Lee, K.T. Kang, W.C. Hsu, In reference to supraglottoplasty for laryngomalacia with obstructive sleep apnea: a systematic review and meta-analysis, Laryngoscope (2016) 1–10. J.W. Schroeder, N.D. Bhandarkar, L.D. Holinger, Synchronous airway lesions and outcomes in infants with severe laryngomalacia requiring supraglottoplasty, Arch. Otolaryngol. Head. Neck Surg. 135 (2009) 647–651. G.T. Richter, C.T. Wootten, M.J. Rutter, D.M. Thompson, Impact of supraglottoplasty on aspiration in severe laryngomalacia, Ann. Otol. Rhinol. Laryngol. 118 (2009) 259–266. K.E. Day, C.M. Discolo, J.D. Meier, B.J. Wolf, L.A. Halstead, D.R. White, Risk factors for supraglottoplasty failure, Otolaryngol. – Head. Neck Surg. 146 (2012) 298–301. V.H. Ramprasad, M.A. Ryan, A.E. Farjat, R.J. Eapen, E.M. Raynor, Practice patterns in supraglottoplasty and perioperative care, Int. J. Pediatr. Otorhinolaryngol. 86 (2016) 118–123.
Contents lists available at ScienceDirect
International Journal of Pediatric Otorhinolaryngology journal homepage: www.elsevier.com/locate/ijporl
A novel technique for unilateral supraglottoplasty☆
T
∗
Harry H. Ching , Alycia G. Spinner, Nathaniel H. Reeve, T.J. O-Lee Department of Otolaryngology - Head and Neck Surgery, University of Nevada Las Vegas School of Medicine, 1701 W. Charleston Blvd., Suite #490, Las Vegas, NV 89102, USA
A R T I C L E I N F O
A B S T R A C T
Keywords: Supraglottoplasty Congenital laryngomalacia Pediatric airway
Objectives: Traditional supraglottoplasty for pediatric laryngomalacia is most commonly conducted with either CO2 laser or cold steel instruments. While the procedure enjoys high success rates, serious complications such as excessive bleeding, supraglottic stenosis and aspiration can occur. Unilateral coblation supraglottoplasty may reduce this risk, but data on respiratory and swallowing outcomes are lacking. This study reports our experiences with unilateral coblation supraglottoplasty. Methods: Pediatric patients with severe congenital laryngomalacia who underwent unilateral supraglottoplasty at a single institution from 2013 to 2016 were retrospectively reviewed. Bipolar radiofrequency ablation (Coblation) was utilized with partial arytenoidectomy, aryepiglottoplasty, and advancement of mucosal flaps. Outcome measures included apnea-hypopnea index (AHI), weight-by-age percentile, and decannulation rate. Results: Twelve patients were included with an average age of 13.1 months (range 2–28 months). In patients without tracheostomy, 88% had complete resolution of respiratory symptoms, while the remainder had significant improvement. In patients without gastrostomy tubes, there was an average increase in weight-age percentile of 6.1, 7.8, and 15.3 points at 1, 3, and 6 months postoperatively, respectively. Three patients had complete polysomnography data with a mean preoperative AHI of 19.3 and postoperative AHI of 4.0. Three of four patients with tracheostomy have been decannulated at a mean follow-up of 1.5 years. There were no early or late postoperative complications and no revision supraglottoplasty. Conclusion: Unilateral supraglottoplasty with bipolar radiofrequency ablation can improve respiratory symptoms and decrease OSA severity in severe congenital laryngomalacia. This technique is safe and can lead to substantial improvement in AHI in patients with OSA.
1. Introduction Laryngomalacia is the most common congenital laryngeal anomaly and a common cause of stridor in infants [1]. The characteristic finding is varying degrees of airway obstruction caused by collapse of redundant supraglottic tissue. Patients generally present with inspiratory stridor shortly after birth which worsens in the first several months of life. In the majority of patients, laryngomalacia is self-limited and resolves with empiric medical treatment for gastroesophageal reflux disease (GERD). In up to 20% of patients with laryngomalacia, surgical management is needed due to a severe presentation or worsening of symptoms despite conservative treatment [2]. These patients may have cyanotic episodes, severe OSA, dysphagia, and failure to thrive. Supraglottoplasty (SGP) is currently the most common surgical treatment for severe laryngomalacia [3]. Using a CO2 laser or cold instruments, bilateral arytenoids are trimmed and the aryepiglottic
folds are divided to increase the supraglottic airway. Although rare, supraglottic stenosis and aspiration can occur following bilateral SGP [3]. Supraglotic stenosis has been reported in up to 4% of patients and can lead to multiple revision airway surgeries or tracheostomy-dependence [4]. Subsequently, unilateral supraglottoplasty has been increasingly investigated to minimize the risk of supraglottic stenosis. Bipolar radiofrequency ablation (RFA) devices have become increasingly popular for laryngeal applications, such as in respiratory papillomatosis. These devices reduce airway fire risk and heat induced thermal injury compared to the CO2 laser. They also allow simultaneous endoscope use in the off-hand and can enhance visualization. Two characteristics of our technique for unilateral SGP have not been previously described in detail: 1) the use of a bipolar radiofrequency ablation device and 2) the advancement and suturing of mucosal flaps to increase the laryngeal airway and reduce the demucosalized surface area. Data on respiratory and swallowing outcomes in unilateral SGP have been limited to a few case series [2,5,6]. This study aims to
☆ ∗
Presented at the 2016 AAO-HNS Annual Meeting, San Diego, CA USA on September 18, 2016. Corresponding author. E-mail addresses: [email protected] (H.H. Ching), [email protected] (A.G. Spinner), [email protected] (N.H. Reeve), [email protected] (T.J. O-Lee).
https://doi.org/10.1016/j.ijporl.2017.11.003 Received 12 September 2017; Received in revised form 2 November 2017; Accepted 3 November 2017 Available online 06 November 2017 0165-5876/ © 2017 Elsevier B.V. All rights reserved.
International Journal of Pediatric Otorhinolaryngology 104 (2018) 150–154
H.H. Ching et al.
describe our experience with the use of a bipolar RFA device for supraglottoplasty and to evaluate the complications and efficacy of this technique.
area. The airway is examined for patency under spontaneous ventilation. The patient is generally extubated prior to returning to the postanesthesia care unit.
2. Materials and methods
2.3. Definitions
2.1. Patient identification and management
Weight by age percentile was calculated using the 2006 WHO Growth Standard Charts for patients aged 0–24 months of age and the 2000 CDC Growth Charts for 2–20 years of age. When applicable, weight by age percentile for preterm patients was corrected and calculated using the 2013 Fenton Growth Charts. Prolonged intubation was defined as a period greater than 2 weeks. Severe laryngomalacia on flexible laryngoscopy was defined as a narrowed laryngeal airway with the following features: 1) inward collapse of mucosa of the arytenoids and aryepiglottic folds, 2) collapse of the epiglottis inwards during inspiration, and 3) short aryepiglottic folds. Moderate laryngomalacia was defined as a narrowed laryngeal airway with at least 1 of the signs of laryngomalacia on laryngoscopy. The pediatric OSA grading system proposed by Katz et al. [8] was used as follows: 1) severe OSA: OAHI ≥ 10 or an SpO2 nadir ≤ 75%, 2) moderate OSA: OAHI between 5 and 9 or SpO2 nadir between 76% and 85%, 3) mild OSA: OAHI between 1 and 5. Potential complications included any intervention requiring return to the operating room in the perioperative period, worsening aspiration, severe respiratory events requiring re-intubation or noninvasive ventilation, postoperative hemorrhage, and supraglottic stenosis.
This is a retrospective case series of pediatric patients with congenital laryngomalacia who underwent unilateral supraglottoplasty from 2014 to 2016. Prior to 2014, supraglottoplasty was performed with CO2 laser in a bilateral fashion at our institution. Pediatric patients who underwent unilateral supraglottoplasty were identified using case logs. Indications for supraglottoplasty in this cohort included: 1) evidence of laryngomalacia with airway compromise on flexible or direct laryngoscopy and 2) symptoms of moderate to severe laryngomalacia such as recurrent stridor, OSA, dysphagia with failure to thrive, and recurrent episodes of apnea or cyanosis. Exclusion criteria included a history of open or endoscopic laryngeal surgery prior to supraglottoplasty. This study was approved by the University of Nevada School of Medicine Institutional Review Board. Preoperative workup included a full history and physical examination with flexible laryngoscopy. Patients with endoscopic findings of laryngomalacia were treated with a trial of acid-suppression therapy and monitored for worsening of symptoms. After publication of the 2016 Laryngomalacia Consensus Recommendations by the International Pediatric ORL Group (IPOG), patients were managed according to acid suppression “step-up” guidelines [7]. Whenever possible, preoperative and postoperative polysomnography (PSG) was obtained. Postoperatively, patients without tracheostomy were routinely admitted to the pediatric intensive care unit and were often discharged the next day. Patients with tracheostomy and without severe comorbidities were discharged the same day. Oral diet was started immediately after surgery and pain was generally controlled with a combination of ibuprofen and acetaminophen. All patients were routinely given antibiotics, acid suppression, and one week of systemic steroids. Patients were maintained on or weaned from acid suppression therapy according to the IPOG post-surgical treatment algorithm [7]. Flexible laryngoscopy was repeated at regular intervals to assess for residual laryngomalacia.
2.4. Data and statistical analysis Data collected from chart review included demographic information, preoperative symptoms, comorbidities, and patient weight at each clinic visit. Operative data included operative findings, procedural details, and operative time. Inpatient data included medication use, oxygen requirements, length of ICU and hospital stay. Postoperative data included hospital readmissions for respiratory reasons, tracheostomy weaning, and additional airway procedures. Primary outcome measures included resolution of symptoms, tracheostomy decannulation, change in OAHI, change in swallowing and weight percentile, revision supraglottoplasty, and additional airway procedures. Statistical analysis was carried out using SPSS Statistics 20 (IBM Corp, Armonk, NY).
2.2. Surgical technique 3. Results All surgical procedures were performed by the senior author (T.J.O.). General anesthesia was induced with gas anesthetic via mask. Direct laryngoscopy was performed using an appropriate-sized Parsons laryngoscope and the patient was suspended on the Mayo stand. With the patient spontaneously ventilating, a complete evaluation of the airway was performed to rule out synchronous airway lesions. Because of the diminished fire risk with bipolar radiofrequency, performing supraglottoplasty with an endotracheal tube in place is a viable alternative to traditional general anesthesia under spontaneous ventilation. The bipolar radiofrequency ablation device used in this study was the COBLATION Microlaryngeal Wand (Smith & Nephew, London, UK). A zero-degree Hopkins rod with high magnification is used in the off-hand for visualization. Unilateral supraglottoplasty was generally carried out on the right side if the arytenoid cartilages and mucosa were symmetric. See Fig. 1. The aryepiglottic fold is routinely divided first. The mucosa overlying the arytenoid cartilage is ablated until the arytenoid cartilages are exposed. A small amount of arytenoid cartilage is ablated while preserving medial and lateral mucosal flaps around the arytenoid (see Fig. 1B). The mucosal flaps are then approximated using one or two 4-0 Vicryl sutures which are tied with an endoscopic knot pusher (see Fig. 1C). The Vicryl sutures serve two purposes: 1) lateralization of the medial mucosal flap to maximize the laryngeal airway and 2) facilitation of postoperative healing by reducing the demucosalized surface
A total of 15 patients underwent unilateral supraglottoplasty in the study period, with three patients excluded due to prior or additional endoscopic or open laryngoplasty. A total of 12 patients were included in the final analysis, with a mean age of 13.1 months. The majority of patients (67%) were full term, with only two patients extremely preterm (< 28 weeks). The most common comorbidity was neurologic (42%) which included agenesis of the corpus callosum, traumatic brain injury, cerebral palsy, and lissencephaly. Cardiac (25%) and pulmonary (25%) comorbidities included pulmonary hypertension, recurrent pneumonia, arrhythmia, and patent foramen ovale. Subjective dysphagia and swallowing difficulties were a common presenting symptom, found in 75% of patients, with 42% of patients having a gastrostomy tube preoperatively. Synchronous airway lesions were found in two patients, including one patient with tracheomalacia and one with subglottic stenosis (Cotton-Meyer Grade 3). See Table 1. Supraglottoplasty was right-sided in all patients and included division of the right A-E fold and partial arytenoidectomy with approximation of mucosal flaps. The total procedure duration was a mean of 40.1 min. All three patients with an existing tracheostomy were discharged the same day. Of the nine patients without a prior tracheostomy, eight were observed overnight in the pediatric ICU and discharged the next day. The ninth patient had an extended stay of four 151
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Fig. 1. Severe laryngomalacia in an 8 week old female. A: Pre-operative larynx. B: Mildly improved laryngeal airway after division of the right aryepiglottic fold and partial arytenoidectomy. C: Significantly improved laryngeal airway after approximating the mucosal edges with a single vicryl suture.
Table 1 Preoperative clinical characteristics.
Table 2 Operative and postoperative characteristics.
Characteristic
Never Trach Dependent
Trach Dependent
Decannulated
Overall
Characteristic
Pre-op Tracheostomy
No Tracheostomy
Overall
Total Patients Mean Age (m)
8 11.6
1 20.5
3 14.5
Number of Patients Operative Procedure Right-sided supraglottoplasty A-E fold Partial arytenoidectomy Operative time (min)
3
9
12
3 (100%)
9 (100%)
12 (100%)
3 (100%) 3 (100%) 43.5
9 (100%) 9 (100%) 39.3
Admitted postoperatively Supplemental Oxygen Requirement ICU Length of Stay (days)
0 0
9 (100%) 3 (33%)
12 (100%) 12 (100%) 40.1 (range 20–108) 9 (75%) 3 (25%)
0
1.4 (range 1–4)
Total Hospital Stay (days)
0
1.7 (range 1–4)
Hours until PO intakea Additional airway intervention prior to discharge
2.0 –
5.6 0
Female 3 Gestational Age Full Term 5 32 - < 37 weeks 2 28 - < 32 weeks 0 < 28 weeks 1 Comorbidities Neurologic 3 Cardiac 2 Pulmonary 1 Syndromic 0 H/o prolonged 1 Intubation Synchronous 2 Airway Lesion Laryngomalacia Severity Moderate 2 Severe 6 Dysphagia 5 G-tube 2 dependence Weight-age percentile 2 to < 5 1 <2 2
0
1
12 13.1 (range 2–28.3) 4 (33%)
1 0 0 0
2 0 0 1
8 (67%) 2 (17%) 0 2 (17%)
1 0 1 0 1
1 1 1 0 0
5 3 3 0 2
0
0
2 (17%)
0 1 1 1
0 3 3 2
2 (17%) 10 (83%) 9 (75%) 5 (42%)
0 0
1 0
2 (17%) 2 (17%)
(42%) (25%) (25%) (17%)
1.0 (range 0–4) 1.2 (range 0–4) 5.2 0
Values are means unless otherwise specified. a Patients without G-tube. Table 3 Respiratory outcomes.
Values indicate number of patients unless otherwise specified.
days due to limited PO intake. The patients began PO intake an average of 5.6 h after surgery. Only three patients required supplemental oxygen during the postoperative hospital stay. There were no complications in the immediate postoperative period. No patients required reintubation, non-invasive ventilation, or racemic epinephrine. See Table 2. Of the patients without a gastrostomy tube, two patients met criteria for failure-to-thrive (FTT) preoperatively. These patients had an increase in weight-by-age percentile (WAP) of 1 and 16.3 points at 3 month follow-up. Overall, the eight patients without gastrostomy tubes had an average increase in WAP of 6.1, 7.8, and 15.3 points at 1, 3, and 6 months postoperatively, respectively. There were 8 patients in the cohort who never had a tracheostomy, and seven of those had complete resolution of stridor and choking symptoms by 3 months postoperatively. The other patient had subjective improvement with a reported decreased frequency and severity of stridor. Three patients had both preoperative and postoperative PSG, and one patient had only postoperative PSG. The mean preoperative and postoperative OAHI was 19.3 and 4.0, respectively. There was a mean decrease in OAHI of 14.9 points. Of the patients with postoperative PSG, one patient had completely resolved OSA with
Characteristic
Patients
Patients Never Requiring Tracheostomy Symptomatic Improvement No Improvement Significant Improvement Complete Resolution Patients with postoperative PSG Mean Change in AHI Mean Postoperative AHI
8 0 1 7 4 - 14.9 4.0
Patients with preop tracheostomy Postoperative tracheostomy Decannulated
3 1 3
Values are numbers of patients unless otherwise specified.
OAHI < 1 and two patients had mild OSA with OAHI < 5. The fourth patient had a postoperative OAHI of 11, which was improved from the preoperative OAHI of 26. See Table 3. Three patients had a tracheostomy preoperatively, and one patient underwent tracheotomy 6 weeks after supraglottoplasty due to prolonged ventilator dependence secondary to pneumonia. The patient who underwent postoperative tracheotomy had drastic improvement in stridor and slow feeding in the postoperative weeks leading up to his hospitalization for pneumonia. He was eventually decannulated 4 months later. Of the three patients with tracheostomy prior to supraglottoplasty, two were successfully decannulated at 3 and 24 months 152
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Published series of unilateral supraglottoplasty have reported that 15–40% of patients will require a second stage or contralateral supraglottoplasty [2,5,6]. On postoperative laryngoscopy, no patients in this series had signs of significant residual laryngomalacia requiring revision supraglottoplasty. One possibility is that the lateralization of mucosal flaps of the arytenoid which may improve the supraglottic airway. Additionally, authors of other studies may have different indications for a staged contralateral supraglottoplasty. Bilateral supraglottoplasty may be associated with an up to 10% risk of significant complications such as postoperative edema with obstruction, worsening dysphagia, and supraglottic stenosis [3,4,14,15]. Supraglottic stenosis has been reported to occur in up to 4% of cases of bilateral supraglottoplasty [4], and although it is a rare complication, it can lead to multiple revision procedures or long-term tracheostomy dependence. Unilateral supraglottoplasty theoretically minimizes the risk of supraglottic stenosis by avoiding the proximity of two demucosalized arytenoid surfaces in contact during healing, which may prevent scar and adhesion formation. Our technique of suturing the mucosa may further reduce the demucosalized surface area and risk of scar formation. Indeed, to the best of our knowledge, there is not a reported case of supraglottic stenosis after the unilateral procedure in the current literature, including this series [2,5,6]. Walner et al. proposed a staged strategy of unilateral supraglottoplasty followed by contralateral supraglottoplasty several months later if symptoms persisted, which also theoretically avoids supraglottic stenosis with the potential benefit of the bilateral procedure [2]. This is the first case series describing outcomes of supraglottoplasty using a bipolar radiofrequency ablation device. In a survey of 101 otolaryngologists regarding supraglottoplasty practice patterns, cold steel was the most popular surgical technique, being used by 73% of respondents, followed by laser with 14% [16]. One major advantage of the low temperature RFA devices is the lack of airway fire risk, and therefore the entire procedure can be performed with a standard endotracheal tube in place. It also has the advantage over the CO2 laser of providing tactile feedback during ablation, to accurately determine depth towards the arytenoid cartilages. Bipolar RFA devices are excellent at achieving hemostasis while simultaneously ablating tissue, which is one advantage over the cold steel technique. Limitations of this study include those associated with retrospective case series. Certain subsets of data were extremely limited, such as PSG data because it was not routinely obtained for every patient in the series preoperatively. Swallowing outcomes were not measured objectively and therefore had to be indirectly inferred from weight percentile values. This is also a relatively small series, which limits comparison of outcomes to other studies of supraglottoplasty.
postoperatively. The patient requiring 24 months for decannulation also had Grade 3 subglottic stenosis requiring three dilations prior to supraglottoplasty, and at the time of decannulation, his subglottic stenosis was found to have improved to Grade 2. One patient remains tracheostomy dependent at 2 year follow-up and is progressing towards decannulation. Of note, this patient has severe neurologic deficits due to past traumatic brain injury. No patients have required revision supraglottoplasty or additional major airway procedures after unilateral supraglottoplasty, other than tracheotomy. 4. Discussion In this case series, pediatric patients with severe congenital laryngomalacia were treated with unilateral supraglottoplasty using a technique with two novel characteristics. These characteristics are: 1) the use of a bipolar RFA device and 2) vicryl sutures to increase the laryngeal airway by lateralizing the arytenoid mucosa and reducing the demucosalized surface area. Patients had moderate to complete improvement in respiratory symptoms, and there were no significant complications. In 1990, Katin and Tucker were the first to describe the potential efficacy of unilateral SGP [9]. Kelly and Gray [5] were the first to analyze outcomes for a series of patients who underwent unilateral CO2 laser supraglottoplasty for severe laryngomalacia. There were no major complications and a success rate of 94% with 3 of 18 patients requiring a subsequent contralateral SGP. Reddy et al. reported a series of unilateral SGP in 47 patients with a success rate of 96% and a contralateral procedure required in 15% of patients [6]. Complications included new postoperative aspiration in 8.5% of patients but no supraglottic stenosis. Walner et al. reviewed 15 patients who underwent staged unilateral SGP and found 100% had resolution respiratory symptoms by the second stage, with 40% of patients requiring the second stage or contralateral SGP. Of note, patients with neurologic comorbidities were excluded in that study. In the current study, 11 of 12 patients achieved decannulation or moderate to complete resolution of respiratory symptoms, while the remaining patient is progressing towards decannulation. Of the patients without tracheostomy, 88% achieved complete resolution of symptoms while the remainder had significant improvement. Marcus et al. in 1990 were among the earliest to report improvement in PSG parameters following SGP in four of six patients [10]. Zafereo reported a significant improvement in PSG parameters for 10 patients with congenital laryngomalacia who underwent bilateral SGP and found a mean improvement in OAHI from 12.2 to 4.2 [11]. More recently, there are a growing number of studies of SGP for OSA due to sleep-dependent laryngomalacia which can present in older pediatric patients. A meta-analysis of SGP for OSA in laryngomalacia by Lee et al. found a mean AHI improvement from 14.0 to 3.3 for sleep-dependent laryngomalacia and 20.4 to 4.0 for congenital laryngomalacia [12]. Patients in this study with complete PSG data showed a mean improvement in OAHI of 14.9 points, with all three patients having resolved or mild OSA postoperatively. Although the limited number of patients in this study with complete PSG data prevents a comparison to published OSA data in bilateral SGP, unilateral SGP may be able to treat OSA associated with severe congenital laryngomalacia. The incidence of tracheostomy-dependence for patients undergoing bilateral supraglottoplasty has been reported to be 3–14% when including patients with severe comorbidities [3,13]. Studies of unilateral supraglottoplasty have had 0–13% of patients requiring tracheotomy [2,5,6]. In the current literature, there does not appear to be a major difference in the incidence of tracheostomy-dependence between unilateral and bilateral supraglottoplasty, but further studies are needed. Risk factors for tracheotomy in these patients include synchronous airway lesions and severe neurologic comorbidity [2,13]. In this series, one patient had to undergo tracheotomy 6 weeks postoperatively for prolonged intubation due to pneumonia.
4.1. Conclusion Unilateral supraglottoplasty with bipolar radiofrequency ablation can improve respiratory symptoms and OSA severity in severe congenital laryngomalacia. This technique is safe and can lead to substantial improvement in AHI in patients with OSA. Conflicts of interest None. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Acknowledgements None. 153
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