Risk Factors for Perioperative Respiratory Failure following Mandibular Distraction Osteogenesis for Micrognathia: A Retrospective Cohort Study

Computerized Surgical Planning for Mandibular Distraction Osteogenesis

Mandibular distraction osteogenesis is a technically challenging procedure due to complex mandibular anatomy, especially in the treatment of Pierre-Robin Sequence due to variable bone thickness in the infant mandible and the presence of tooth buds. Computerized surgical planning (CSP) simplifies the procedure by preoperatively visualizing critical structures, producing cutting guides, and planning distractor placement. This paper describes the process of using CSP to plan mandibular distraction osteogenesis, including discussion of recent advances in the use of custom distractors.

Mandibular Distraction in Patients With Pierre Robin Sequence: A Multisurgeon Experience

OBJECTIVE

Mandibular distraction osteogenesis (MDO) is rapidly becoming a standard of care for management of patients with severe Pierre Robin sequence. The tongue is brought forward to alleviate airway obstruction. This study will look at an institutional, multisurgeon experience with MDO over 10 years.

DESIGN

A retrospective chart review was conducted.

SETTING

All patients who underwent MDO at the authors' institution from 2012 to 2022 were included. Three craniofacial surgeons performed all interventions.

PATIENTS

Demographics, preoperative and postoperative respiratory and feeding status, and distraction data were collected for 27 patients meeting inclusion criteria.

MAIN OUTCOME MEASURES

Primary outcomes were avoidance of a gastrostomy tube, avoidance of a tracheostomy, discharge from hospital on room air, and complications. A significance value of 0.05 was utilized.

RESULTS

The average age at MDO was 135 days, mean activation phase was 13.6 days, mean distraction length was 14.9 mm, and mean consolidation phase was 64.2 days. A longer activation phase was associated with discharge with a gastrostomy tube and a shorter activation phase was associated with discharge on full oral feeds. The ability to discharge on room air was associated with a shorter latency phase, shorter activation phase, and decreased distance of distraction.

CONCLUSIONS

The goal of MDO is to achieve full oral feeds with no respiratory support. Several different latency periods were used in this study, and a short latency period was demonstrated to be safe.

Weight Gain of Infants with Robin Sequence Treated Nonsurgically Using the Stanford Orthodontic Airway Plate (SOAP): 1-Year Follow-Up

OBJECTIVE

To identify weight gain trends of infants with Robin sequence (RS) treated by the Stanford Orthodontic Airway Plate treatment (SOAP).

DESIGN

Retrospective longitudinal cohort study.

SETTING

Single tertiary referral hospital.

PATIENTS

Eleven infants with RS treated with SOAP.

INTERVENTIONS

Nonsurgical SOAP.

MAIN OUTCOME MEASURES

Body weight, Weight-for-age (WFA) Z-scores, and WFA percentiles at birth (T0), SOAP delivery (T1), SOAP graduation (T2), and 12-months old (T3).

RESULTS

Between T0 and T1, the weight increased but the WFA percentile decreased from 36.5% to 15.1%, and the Z-score worsened from -0.43 to -1.44. From T1 to T2, the percentile improved to 22.55% and the Z-score to -0.94. From T2 to T3, the percentile and the Z-scores further improved to 36.59% and -0.48, respectively.

CONCLUSIONS

SOAP provided infants experiencing severe respiratory distress and oral feeding difficulty with an opportunity to gain weight commensurate with the WHO healthy norms without surgical intervention.

Comprehensive Long-Term Outcomes Following Mandibular Distraction Osteogenesis

OBJECTIVE

To describe long-term outcomes and complications following mandibular distraction osteogenesis (MDO) in a diverse patient cohort.

DESIGN

Cross-sectional study.

SETTING

Single tertiary-care pediatric center.

PATIENTS

Forty-eight patients previously undergoing MDO with minimum 4-year follow-up.

MAIN OUTCOME MEASURES

Respiratory outcomes, feeding patterns, dental development, motor/sensory nerve function, temporo-mandibular joint function, and postsurgical scarring.

RESULTS

Forty-six patients with a median age of 7 years were evaluated. Of 20 nonsyndromic patients, none required additional airway procedures, none required continuous positive airway pressure (CPAP) during sleep, and 19 (95%) fed exclusively by mouth. Among 26 syndromic patients, 7 (27%) required CPAP and 8 (31%) were tube fed. Permanent first molar differences were seen in the majority of subjects; patterns of damage interfering with function were more common in syndromic (13/28, 46%) compared to nonsyndromic (5/24, 21%; P = .014) subjects. MDO prior to age two was associated with more frequent and worse dental damage (P = .001). Inferior alveolar nerve and marginal mandibular nerve function were fully intact in 37 (80%) and 39 (85%) of patients, respectively. Three patients (6%), all with associated genetic syndromes, demonstrated severe nerve impairment. By the Vancouver scar scale, ≥ 80% of surgical scars were rated in the most favorable category for each quality assessed. Temporomandibular joint dysfunction was rare.

CONCLUSIONS

MDO shows highly favorable long-term respiratory, feeding, nerve, and scar outcomes in nonsyndromic patients, although permanent molar changes not precluding tooth viability are commonly seen. Patients with associated syndromes demonstrate respiratory and feeding benefits, but higher rates of dental and nerve abnormalities.

Mandibular morphology and distraction osteogenesis vectors in patients with Robin sequence

The aims of this cohort study were to compare the mandibular morphology between patients with Robin sequence (RS) and controls, and to examine the effects of mandibular distraction osteogenesis (MDO) using different vectors. Measurements of the mandibles of 80 patients with RS and 46 controls aged< 90 days were made using computed tomography. The data were compared among isolated RS patients (n = 58), syndromic RS patients (n = 22), and controls. Patients with RS exhibited significantly shorter ramus and body lengths and larger symphyseal angles than controls (all P < 0.001). Patients with isolated RS had shorter body lengths (P < 0.001), while syndromic patients had shorter ramus and body lengths (both P < 0.001) than controls. Seventy RS patients underwent MDO. Pre-MDO (n = 37) and post-MDO (n = 29) mandibular measurements were compared between patients undergoing MDO with a vertical vector and those undergoing MDO with a horizontal vector. Polysomnography data from part of the cohort highlighted the effectiveness of both vectors. MDO with a horizontal vector conferred 11% and 36% increases in ramus and body length, respectively, while these increases were 34% and 27.5%, respectively, with a vertical vector. MDO with a vertical vector was effective in lengthening ramus and body components and should be considered in the presence of ramus hypoplasia.

Cleft Palate Repair in Robin Sequence following Mandibular Distraction Osteogenesis Compared to Tongue-Lip Adhesion

OBJECTIVE

To evaluate the timing and safety of cleft palate (CP) repair in patients with Robin sequence (RS) treated with mandibular distraction osteogenesis (MDO) or tongue-lip adhesion (TLA) for airway obstruction.

DESIGN

Retrospective cohort study.

SETTING

Tertiary Pediatric Hospital during 2004-2020.

PATIENTS

148 patients with RS underwent MDO, 66 met inclusion by having MDO and followed by palatoplasty. 26 patients with RS underwent TLA, 14 met inclusion by having TLA and followed by palatoplasty.

MAIN OUTCOME MEASURES

Patient characteristics, hospital/operative details, postoperative complications, and polysomnographic (PSG) data were compared.

RESULTS

Groups were well-matched except more patients with syndromes underwent MDO (N = 27, 41%, P ≤ .002). In the MDO and TLA cohorts, mean CP repair age was 12.8 ± 1.9 months and 14.6 ± 1.6 months, respectively (P ≤ .002). Despite the earlier CP repair in the MDO group, there were no differences in peri-operative complication rates after palatoplasty in either group. All sleep respiratory parameters improved after MDO/TLA prior to palatoplasty P ≤ .050. All PSG parameters remained significantly improved after palatoplasty compared to preoperative values, P ≤ .043. Obstructive apnea hypopnea index and Oxygen saturation nadir further improved after palatoplasty within the MDO group, P ≤ .050, while no changes in the TLA group, P ≥ .500.

CONCLUSIONS

MDO was associated with earlier age at palatoplasty than TLA with a similar perioperative risk profile. In those patients with pre- and post-palatoplasty PSG data, palatoplasty was not associated with a deterioration in PSG parameters, and in fact in the MDO group, PSG data improved.

Mandibular Distraction in Neonatal Pierre Robin Sequence: Is Immediate Extubation Both Feasible and Safe?

BACKGROUND

The timing of extubation following placement of mandibular distractors in the setting of Pierre Robin sequence is variable across institutional algorithms. Postoperative maintenance of intubation allows for an improvement in airway dimension and tongue positioning before extubation, theoretically decreasing the impact of postoperative airway edema. Maintenance of intubation, however, is not without risk. The authors analyze their institutional experience with neonatal mandibular distraction followed by immediate extubation to assess feasibility and safety profiles.

METHODS

A 4-year retrospective review of patients diagnosed with Pierre Robin sequence who underwent mandibular distraction within the first 3 months of life was performed. Patients intubated preoperatively were excluded.

RESULTS

Fifty-two patients met inclusion criteria. Thirty-eight patients (73 percent) were extubated immediately, whereas 14 patients (27 percent) remained intubated. No differences between these groups were found when comorbidities, cleft pathology, preoperative respiratory support, or grade of view on direct laryngoscopy were analyzed. Case duration greater than 120 minutes, operation start time after 3 pm, and the subjective designation of a difficult airway by the anesthesiologist were associated with maintaining intubation (p < 0.05). Eight patients (21 percent) in the extubated group required an increase in respiratory support in the postoperative interval. Four of these patients (11 percent) required reintubation. Increased postoperative respiratory support was more likely in patients with certain comorbidities and higher preoperative respiratory support requirements (p < 0.05).

CONCLUSIONS

The authors' data suggest that immediate extubation following neonatal mandibular distraction is feasible in patients who are not intubated preoperatively. Careful consideration should be given to patients who require significant respiratory support preoperatively and in those with certain comorbidities.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

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.

Mandibular Distraction Osteogenesis for Tongue-Based Airway Obstruction Without Micrognathia

PURPOSE

Mandibular distraction osteogenesis (MDO) effectively treats tongue-based airway obstruction (TBAO) in micrognathic patients with Robin Sequence. Mandibular distraction osteogenesis may also address TBAO in certain nonmicrognathic patients who have severe obstructive apnea, although there is no current literature to guide MDO use in these atypical patients. This study describes outcomes of MDO in a series of patients with TBAO without micrognathia.

METHODS

Patients who underwent MDO for TBAO from 2013-20 were reviewed, and patients with micrognathia were excluded. Study subjects received baseline/follow up polysomnography. Polysomnography variables, including Obstructive Apnea Hypopnea Index, oxyhemoglobin saturation nadir (SpO2 nadir), percent sleep time end tidal CO2 greater than 50 mm Hg (%ETCO2 > 50), and respiratory-related arousals were compared before and after MDO. Demographics, syndromic/cleft palate status, airway anomalies, respiratory support, and feeding outcomes were collected.

RESULTS

One hundred and twenty-four patients underwent MDO during this study period; 5 were nonmicrognathic and included in analysis. Sixty percent (n = 3) of the cohort was syndromic: 1 patient each had Trisomy 9, Beckwith Wiedemann syndrome, and duplicated pituitary gland plus syndrome. Forty percent (n = 2) of patients had a cleft palate, 60% (n = 3) had laryngomalacia, and 40% had tracheomalacia. Median (range) age at MDO was 53 days (47-167 days), and median length of distraction was 16 mm (14-20 mm). After MDO, median Obstructive Apnea Hypopnea Index decreased from x̃ = 60.7/h (11.6-109.4) to x̃ = 5.3/h (3.5-19.3) (P = 0.034). SpO2 nadir increased (69% [58-74] to 85% [80-88], P = 0.011), and median %ETCO2 > 50 mm Hg decreased (5.8% [5.2-30.1] to 0.0% [0.0-1.3], P ≤ 0.043). Continuous positive airway pressure was used by all patients immediately after MDO, and at 6 months postoperatively, 1 patient remained on continuous positive airway pressure and 1 patient required supplemental oxygen. At last follow up, no patients had significant residual airway obstruction or required a tracheostomy.

CONCLUSIONS

Mandibular distraction osteogenesis can effectively treat severe TBAO in some patients without micrognathia that would otherwise be candidates for tracheostomy. When used in select patients, MDO significantly improves obstructive sleep apnea and reduces need for ventilatory support, although feeding support is still needed in most patients at 6 months. Further study in a larger cohort will help identify appropriate candidates for MDO and characterize outcomes of unique patient populations.

A Standardized Extubation Schedule Reduces Respiratory Events After Extubation Following Mandibular Distraction in Infants

PURPOSE

The rational time for intubation during early mandibular distraction osteogenesis (MDO) in infants is unknown. To investigate the differences in clinical outcomes following MDO before and after a standardized extubation protocol implementation in infants.

METHODS

A retrospective cohort study was performed for infant patients under 1 year old undergoing MDO. The study population was composed of all patients presenting for evaluation and management who underwent MDO between November 2016 and February 2021. We divided them into 2 groups: the pre-protocol group and the protocol group. The inpatient charts of infants were assessed. The primary outcome was respiratory events after extubation. The secondary outcomes were duration of mechanical ventilation (MV), postoperative length of stay (LOS), and success rate of the first extubation. Other variables included age, sex, weight, height, and information related to diagnosis, distraction, anesthesia, and operation. The logistic regression model and linear regression model were used to calculate unadjusted and adjusted relative risk (RR) and mean difference (MD) for associations between 2 groups and the primary and secondary outcomes.

RESULTS

There were 142 infants in the pre-protocol group and 135 infants in the protocol group. The patients in the protocol group were heavier in weight than those in the pre-protocol group (P<.05). The Cormack-Lehane grade and the duration of operation and anesthesia were higher and longer in the pre-protocol group than in the protocol group (P<.05). Respiratory events after extubation were significantly more common in the pre-protocol group than in the protocol group [21.1 vs. 9.6%, adjusted relative risk 0.46 (95% CI 0.22-0.89), P <.01].

CONCLUSIONS

Among infants undergoing MDO, the standardization of extubation practices can reduce respiratory events after extubation compared with traditional management.

Risk Factors of Prolonged Mechanical Ventilation in Infants With Pierre Robin Sequence After Mandibular Distraction Osteogenesis: A Retrospective Cohort Study

Background: After mandibular distraction osteogenesis (MDO), most infants with Pierre Robin sequence (PRS) require mechanical ventilation to assist their breathing. However, the optimal duration of intubation during early mandibular distraction osteogenesis activation is poorly understood. This retrospective study was carried out to identify perioperative risk factors of prolonged mechanical ventilation in infants undergoing MDO. Methods: A total of 95 infants with PRS underwent MDO at Guangzhou Women and Children's Medical Center between 2016 and 2018, and the clinical records of 74 infants who met the selection criteria were analyzed. Of the 74 infants, 26 (35.1%) underwent prolonged mechanical ventilation, 48 (64.9%) did not. t-test, Wilcoxon Sum Rank test or chi-squared test were performed to compare variables that might associate with prolonged mechanical ventilation between the two groups, and then, significant variables identified were included in the multivariate logistic regression model to identify independent variables. Results: Univariate logistic regression analysis revealed that age, preoperative gonial angle, and postoperative pulmonary infection were associated with prolonged mechanical ventilation (all P < 0.05). Multivariate logistic regression analysis confirmed that the preoperative gonial angle and postoperative pulmonary infection were independent risk factors of prolonged mechanical ventilation (both P < 0.05). Conclusions: Infants with PRS and smaller preoperative gonial angle or postoperative pulmonary infection may be more likely to undergo prolonged mechanical ventilation after MDO. For others, extubation may be attempted within 6 days after MDO.

Short-term condylar and glenoid fossa changes in infants with Pierre Robin sequence undergoing mandibular distraction osteogenesis

The purpose was to evaluate short-term changes in condylar and glenoid fossa morphology in infants with Pierre Robin sequence (PRS) undergoing early (age <4 months) mandibular distraction osteogenesis (MDO) for the management of severe airway obstruction. Computed tomography data from infants with PRS who had MDO were compared to those of age-matched control infants without facial skeletal dysmorphology. Surface/volume, linear, and angular measurements of the condyle and glenoid fossa were obtained and compared between infants with PRS and controls. Eleven infants with PRS met the inclusion criteria. There were five female and six male subjects with a mean age at the time of MDO of 41±32 days. Prior to MDO, PRS mandibles had a smaller condylar articulating surface area and volume than age-matched control mandibles, with a more laterally positioned condylar axis (P≤0.05). Following MDO, there were significant increases in condylar articulating surface area and volume, approaching those of normal controls, with further lateral translation of the condylar axis (P≤0.05). Condyle and glenoid fossa morphology is largely normalized following early MDO in infants with PRS. The condylar axis translates laterally as a result of MDO; this change is not observed with mandibular growth in infants without PRS.

New treatments for obstructive sleep apnea in children

Obstructive sleep apnea (OSA) has a prevalence of up to 5% in children and 50% in obese children. OSA is associated with various comorbidities in the general population and in the perioperative period. In this review, we will provide background of OSA and insights into the available treatment options both surgically and medically. Unlike adults, most pediatric OSA is treated with adenotonsillectomy. Continuous positive airway pressure therapy is the commonly used medical treatment. Management of pediatric OSA is multidisciplinary. We will discuss the surgical options and medical options of managing pediatric OSA.