Evaluation of upper airway obstruction in infants with Pierre Robin sequence and the role of polysomnography--Review of current evidence

Predicting Failure of Conservative Airway Management in Infants with Robin Sequence: The EARN Factors

OBJECTIVE

Evaluate infants with Robin Sequence (RS) who were successfully treated with conservative airway measures alone vs. those who failed and eventually underwent surgical airway intervention after a protracted course of conservative management.

DESIGN

Retrospective review of prospectively gathered database.

SETTING

Large tertiary care institution.

PATIENTS

Infants diagnosed with RS (n = 122) who underwent primary airway management at a single institution from 1994-2020.

MAIN OUTCOME MEASURE

Patient demographics, nutritional and respiratory status, laboratory values, and polysomnographic results were compared between patients who were discharged after successful conservative airway management (Group 1, n = 61) and patients that underwent surgical airway intervention after failing a prolonged course of conservative management (Group 2, n = 61). Receiver operating characteristic (ROC) curve analysis was done to assess continuous variables that may predict failure of conservative airway management.

RESULTS

122 infants with RS were investigated. While several variables were significantly different between groups, the following polysomnographic EARN factors, with cut points, were identified as most predictive of failed conservative airway management: ETCO2 (max) > 49 mmHg, AHI > 16.9 events/hour, OAHI REM >25.9 events/hour, OAHI Non-REM > 23.6 events/hour.

CONCLUSIONS

We identified factors in infants with RS that were associated with severe UAO that failed to improve despite weeks of conservative airway management. Our results may expedite earlier definitive treatment of these critical patients and reduce risks for known complications of prolonged UAO.

Defining Age-related OSA Features in Robin Sequence Using Polysomnographic-based Analyses of Respiratory Arousal Responses and Gas-exchange Parameters

INTRODUCTION

Robin sequence (RS) is a leading cause of obstructive sleep apnea (OSA) in newborns. Most studies have focused on understanding anatomic factors leading to OSA and changes in apnea-hypopnea index (AHI) on polysomnography (PSG) beyond the neonatal period. This study aims to define age-related OSA features between patients with RS, without RS and healthy controls using PSG-based analyses of respiratory arousal responses and gas-exchange parameters.

DESIGN

Retrospective comparison of PSG features in a total of 48 children encompassing three groups: (a) infants with RS (n = 24, <1-year old), (b) non-RS older children (1-2 years old) with severe OSA (obstructive AHI (OAHI) of ≥10 events; n = 12), and (c) control infants and children (0-2 years old) without sleep apnea (OAHI ≤1.5/h, n = 12). We examined OSA sleep-stage specific and position-specific indexes, and the relationship between OSA severity and respiratory arousal indexes (OAHI/respiratory arousal indexes).

RESULTS

OSA sleep-stage specific indexes (rapid eye movement [REM] vs non-REM[NREM]) as well as position-specific indexes (supine vs nonsupine) were similar in individuals with and without RS. Relative to the non-RS groups, infants with RS have more sustained hypoxemia (time with SpO₂ < 90%) and reduced arousal responses to OSA demonstrated by higher OAHI/respiratory arousal indexes. OAHI/respiratory arousal indexes significantly correlated with the severity of hypoxemia in infants with RS.

CONCLUSION

Infants with RS and OSA show reduced arousal responses to apneic events, which correlates with higher hypoxemia severity. OAHI/respiratory arousal indexes in RS may identify high-risk individuals with upper airway obstruction and reduced arousal protective responses.

Multimodal Treatment of Robin Sequence Utilizing Mandibular Distraction Osteogenesis and Continuous Positive Airway Pressure

Mandibular distraction osteogenesis (MDO) and continuous positive airway pressure (CPAP) may each have a role in effectively treating tongue-based airway obstruction (TBAO) in Robin sequence (RS). This study describes longitudinal outcomes after treatment of TBAO with CPAP and/or MDO.

Retrospective cohort study.

Tertiary Pediatric Hospital.

A total of 129 patients with RS treated with CPAP and/or MDO from 2009 to 2019 were reviewed. Subjects receiving baseline and at least one follow-up polysomnogram were included. 55 who underwent MDO ± CPAP and 9 who received CPAP-only treatment were included.

Patient characteristics, feeding, and polysomnographic data were compared and generalized linear mixed modeling performed.

Baseline obstructive apnea-hypopnea index (OAHI) was greater in the MDO-treated group (median x˜ = 33.7 [interquartile range: 26.5-54.5] than the CPAP-treated group (x˜ = 20.3[13.3-36.7], P ≤ .033). There was significant reduction in OAHI following treatment with CPAP and MDO modalities, P ≤ .001. SpO₂ nadir after MDO was lower in syndromic (x˜ = 85.0[81.0-87.9] compared to nonsyndromic patients (x˜ = 88.4[86.8-90.5], P ≤ .005.) CPAP was utilized following MDO in 2/24 (8.3%) of nonsyndromic and 16/31 (51.6%) of syndromic subjects (P ≤ .001,) for a median duration of 414 days. Three patients (5%) underwent tracheostomy, all had MDO. Nasogastric tube feeding at hospital discharge was more common following MDO (44, 80%) than CPAP-only (4, 44.4%, P ≤ .036), but did not differ at 6-month follow-up (P ≥ .376).

CPAP appears to effectively reduce obstructive apnea in patients with RS and moderate TBAO and be a useful adjunct in syndromic patients following MDO with improved but persistent obstruction.

Polysomnography-guided mandibular distraction osteogenesis in Pierre Robin sequence patients

STUDY OBJECTIVES

Craniofacial malformations with micrognathia cause high grades of obstructive sleep apnea (OSA) measured by polysomnography (PSG). Mandibular Distraction Osteogenesis (MDO) is a novel procedure for upper airway obstruction (UAO) relief. Our primary objective was to describe the utilization of PSGs to improve obstruction in patients undergoing mandibular distraction.

METHODS

This is a retrospective study. Patients with micrognathia and severe UAO, presenting with severe OSA diagnosed by PSG, were included from a single tertiary care center between 2015-2019. PSGs were done: (1) prior to surgery, (2) once cosmetic goal was achieved (Post-Op 1) (3) if residual moderate-to-severe OSA was seen, every 2 nights until mild or no OSA was achieved (Post-Op 2).

RESULTS

Thirteen patients were included. The median age at surgery was 1.1months (10 days-3 months). All thirteen patients had baseline severe OSA, with a median obstructive apnea-hypopnea index (OAHI) of 33 events/h and a median O₂ nadir of 73%. Post-Op 1 PSG was done at a median of 6 days after surgery. Median first post-operative OAHI in all 13 patients was 6.8 events/h, with a median O₂ nadir of 87%. A median additional distraction of 3 mm was needed beyond the traditionally recommended advancement. Long term follow-up studies at or after 1year were done in 5 patients, all showing persistent non-severe OSA.

CONCLUSIONS

This is the first case-series utilizing PSGs as a guide for MDO in patients with micrognathia showing the need for jaw over-correction to achieve resolution of OSA.

Prenatal Diagnosis of Robin Sequence: Sensitivity, Specificity, and Clinical Relevance of an Index for Micrognathia

OBJECTIVE

Micrognathia in connection with glossoptosis (called Robin sequence) may lead to life-threatening respiratory problems immediately after birth. An objective detection during prenatal routine ultrasound sonography is possible using an index that relates fetal lower jaw length to femur length or gestational age. The aim of this study was to test the method's sensitivity and specificity and to discuss its predictive power concerning neonatal respiratory insufficiency.

DESIGN

Patients with subjectively identified suspicious signs in the sagittal profile view were included in the study: Two-dimensional serial ultrasound scans of their fetal mandible were used to measure the lower jaw lengths and compare them to predicted values according to an index, derived from 313 healthy fetuses. Follow-up data provided additional information on the clinical appearance of the newborns.

RESULTS

The index showed a high sensitivity: 15 of the 16 cases with a micrognathia were correctly diagnosed (sensitivity of 93.75%). Follow-up data showed that newborns with similar index values differed in terms of their upper airway obstruction and treatment need.

CONCLUSION

Fetal mandibular micrognathia can be objectively evaluated with the help of the index. The method allows an early detection of micrognathia, which helps to take the necessary steps for proper treatment of potential life-threatening respiratory impairment. Observations ranging outside the prediction interval could prompt the ultrasonographer to check for other associated malformations.

Longitudinal Sleep Outcomes in Neonates With Pierre Robin Sequence Treated Conservatively

STUDY OBJECTIVES

Although Pierre Robin sequence (PRS) is a major cause of neonatal obstructive sleep apnea (OSA), longitudinal studies reporting evolution with age are lacking. This study aimed to describe changes in sleep-related respiratory parameters and sleep architecture in neonates with PRS treated conservatively (defined for this paper as treatment without tracheostomy or mandibular distraction).

METHODS

A retrospective, 14-year, single-institution study of neonates with PRS who underwent diagnostic polysomnography (PSG) and at least one follow-up PSG. Those treated with surgery were excluded. Data were analyzed using a mixed-effects model with subject-specific random effect.

RESULTS

In a cohort of 21 infants, baseline PSG (mean age 0.9 ± 0.7 months) showed a total apnea-hypopnea index (AHI) of 24.3 ± 3.6 events/h, obstructive apnea-hypopnea index (OAHI) of 13.4 ± 1.6 events/h, central apnea index of 10.2 ± 3.2 events/h, and an arousal index of 28.3 ± 1.3 events/h (variables reported as least square means ± standard error of the mean). There was a significant reduction in AHI, OAHI, arousal index, and percentage of REM sleep with advancing age. Although 71% of infants achieved full oral feeds by one month of age, some infants remained underweight during infancy.

CONCLUSIONS

These neonates with PRS and OSA, treated conservatively, had an improvement in OAHI with advancing age with the median age of OSA resolution at 15 months. Factors potentially responsible include craniofacial growth and maturational changes of respiratory control. Further studies are necessary to determine the long-term effects of conservative management on growth and neurodevelopmental outcomes in these infants.

Polysomnography Reference Values in Healthy Newborns

STUDY OBJECTIVES

Polysomnography (PSG) is increasingly used in the assessment of infants. Newborn PSG reference values based on recent standardization are not available. This study provides reference values for PSG variables in healthy newborn infants.

METHODS

Cross-sectional study of normal term newborn infants using standardized PSG collection and American Academy of Sleep Medicine interpretation criteria.

RESULTS

Thirty infants born between 37 and 42 weeks gestation underwent PSG testing before 30 days of age (mean 19.6 days). The infants had a mean sleep efficiency of 71% with average proportions of transitional, NREM and REM sleep estimated at 16.1%, 43.3% and 40.6% respectively. Mean arousal index was 14.7 events/h with respiratory arousal index of 1.2 events/h. Mean apnea-hypopnea index (AHI) was 14.9 events/h. Central, obstructive, and mixed apnea indices were 5.4, 2.3, and 1.2 events/h respectively. Mean oxygen saturation in sleep was 97.9% with a nadir of 84.4%. Mean end tidal CO₂ was 35.4 mmHg with an average of 6.2% of sleep time spent above end-tidal CO₂ 45 mmHg and 0.6% above 50 mmHg.

CONCLUSIONS

The sleep efficiency was significantly lower and the AHI was significantly higher compared to healthy children older than 1 year. The AHI was also higher than reported in healthy infants older than 1 month. These findings suggest current severity classifications of sleep apnea may not apply to newborn infants.

Current Trends in Surgical Airway Management of Neonates with Robin Sequence

Background

Robin sequence is defined by the clinical triad of micrognathia, glossoptosis, and upper airway obstruction, and is frequently associated with cleft palate and failure to thrive. Though the efficacy of certain surgical interventions to relieve airway obstruction has been well established, algorithms dictating decision making and perioperative protocols are poorly defined.

Methods

A 22-question survey was sent via e-mail to members of the American Cleft Palate-Craniofacial Association and International Society of Craniofacial Surgeons. Questions were related to surgeon experience in treating neonates with Robin sequence, and specific perioperative protocols.

Results

One hundred fifty-one responses were collected. Most respondents were surgeons practicing in North America(82.8%), in a university hospital setting (81.5%) and had completed a fellowship in pediatric plastic surgery or craniofacial surgery (76.2%). Preoperative protocols varied widely by years in training and location of practice. Although 78.8% of respondents always performed direct laryngoscopy, only 49.7% of respondents routinely obtained preoperative polysomnography. Mandibular distraction osteogenesis was the most common primary surgical airway intervention reported by 74.2%, with only 12.6% primarily utilizing tongue-lip adhesion. Slightly less than half of respondents ever performed tongue-lip adhesion. Operative selection was influenced by surgeon experience, with 80% of those in practice 0-5 years primarily utilizing mandibular distraction, compared with 56% of respondents in practice >15 years.

Conclusions

This study documents wide variations in preoperative, operative, and postoperative protocols for the surgical airway management of neonates with severe Robin sequence. These results underscore the need to acquire more objective data, to compare different protocols and outcome measures.

Upper airway obstruction in neonates: Does sleep exacerbate symptoms?

Objective

Describe the factors that exacerbate upper airway obstructions (UAOs) in neonates.

Study Design

Retrospective chart review.

Setting

Pediatric tertiary care hospital.

Subjects and Methods

All neonates hospitalized between 1/1/2010 and 12/31/2014 diagnosed with either: 1) laryngomalacia, 2) Pierre Robin sequence, or 3) vocal cord paralysis were included in this study. Patient charts were reviewed to determine factors that exacerbated symptoms of airway obstruction. The independent variable was patient diagnosis, and the outcome measure was exacerbating factors.

Results

In patients with laryngomalacia (n = 31), 41.9% worsened with agitation, 38.7% worsened with feeding, 16.1% worsened with positioning, 0.0% worsened during sleep, and 25.8% had no aggravating factors. In Pierre-Robin patients (n = 31), 48.4% worsened with agitation, 16.1% worsened with feeding, 61.3% worsened with positional changes, 0.0% worsened during sleep, and 12.9% had no aggravating factors. In vocal cord paralysis patients (n = 25), 72.0% worsened with agitation, 8.0% worsened with feeding, 20.0% worsened with positional changes, 4.0% worsened during sleep, and 24.0% had no aggravating factors.

Conclusion

Airway obstruction was not reliably exacerbated during sleep for any of the diagnoses studied in this review. Our findings show that agitation exacerbates airway obstruction in most patients with vocal cord paralysis, and positioning exacerbates airway obstruction in the majority of patients with PRS. Aggravating factors in laryngomalacia are variable. These findings question the utility of polysomnography as a diagnostic tool for hospitalized neonates with these conditions.

Level of Evidence

4.

Robin sequence: what the multidisciplinary approach can do

Robin sequence (RS) is a commonly encountered triad of micrognathia, glossoptosis, and airway obstruction, with or without a cleft palate. The management of airway obstruction is of paramount importance, and multiple reviews and retrospective series outline the diagnosis and treatment of RS. This article focuses on the multidisciplinary nature of RS and the specialists’ contributions and thought processes regarding the management of the RS child from birth to skeletal maturity. This review demonstrates that the care of these children extends far beyond the acute airway obstruction and that thorough monitoring and appropriate intervention are required to help them achieve optimal outcomes.

Polysomnographic findings in infants with Pierre Robin sequence

INTRODUCTION:

Pierre Robin sequence (PRS) is characterized by the triad of micrognathia, glossoptosis, and upper airway obstruction. It is commonly associated with the secondary cleft palate. Infants with PRS commonly have sleep-disordered breathing (SDB); including obstructive sleep apnea (OSA) as well as central sleep breathing abnormalities that are present from infancy.

AIM OF THE STUDY:

Evaluate the prevalence and severity of SDB in infants with PRS using polysomnography (PSG).

SETTINGS AND DESIGN:

We retrospectively reviewed the sleep laboratory database at The Hospital for Sick Children, Toronto, during the period of May 2007 to March 2016.

STATISTICAL ANALYSIS:

Comparisons of PSG data were made between the OSA and non-OSA group using the Student's t-test for age and body mass index, Wilcoxon signed ranks test for the continuous PSG data and Chi-squared test for the categorical variables.

METHODS:

Patients with PRS were identified and their initial PSG was selected for this study. The main indication for referral was ongoing concerns regarding OSA symptoms.

RESULTS:

A total of 46 patients (28 females) were included with a mean age (±standard deviation) of 0.8 (±0.3) year. Twenty-two out of 46 (47%) had evidence of OSA of which 10 had mild, 3 had moderate, and 9 had severe OSA. The PRS infants with OSA were younger than the non-OSA group. Significant correlations were found between desaturation and arousal indices with obstructive apnea–hypopnea index.

CONCLUSION:

This retrospective chart review confirms a high prevalence of OSA in this population. Prospective longitudinal studies are needed to evaluate the outcomes of OSA in PRS population.