Clinical outcomes of expansion sphincter pharyngoplasty-a 17-year systematic review

OBJECTIVES

To systematically review long-term (> 5 years) outcomes of ESP surgery for OSA treatment over 17 years.

METHODS

Systemic review of MEDLINE, Google Scholar, Cochrane Library and Evidence Based Medicine Reviews to identify publications relevant to OSA and Expansion Pharyngoplasty and its variants. All relevant studies published between January 2007 and June 2023 were included.

RESULTS

Twelve studies were included in this systematic review with a combined total of 1373 patients who had the ESP procedure were included. The clinical outcomes included encouraging long-term success rate, reductions in Epworth sleepiness scale, good mean disease alleviation, anatomical structural area and volume improvements, blood pressure reductions, biochemical improvements in acute phase reactants after ESP surgery, reductions in intra-ocular pressures, and post-operative reduction of sympathetic overdrive.

CONCLUSIONS

Seventeen years on, the expansion sphincter pharyngoplasty has demonstrated not only increase in anatomical area and volume but significant desired improvements in polysomnographic, clinical and biochemical parameters post-surgery.

International Consensus Statement on Obstructive Sleep Apnea

BACKGROUND

Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).

METHODS

Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.

RESULTS

The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.

CONCLUSION

This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

Expansion sphincter pharyngoplasty in OSA: a 15 year review

OBJECTIVE

A 15 year review of the outcomes and success rates of the Expansion Sphincter Pharyngoplasty (ESP) in the treatment of patients with obstructive sleep apnea (OSA).

METHODS

A systemic review with two independent searches of MEDLINE, Google Scholar, Cochrane Library and Evidence-Based Medicine Reviews to identify publications relevant to OSA and Expansion Pharyngoplasty. All relevant studies published before 31 December 2021 were included.

RESULTS

Sixteen studies were included in this strict systematic review with a total of 747 patients who had the ESP procedure were included. The mean age was 41.3 years, mean BMI 28.2, the mean pre-op AHI was 32.3 and post-op AHI was 10.0 (p < 0.05), the mean pre-op ESS was 11.4, had reduced to post-op 5.3 (p < 0.05), and the mean pre-op snore VAS decreased from 8.7 to 2.9 (p < 0.05), with a mean follow-up time of 9.5 months. The overall pooled success rate for all the 747 patients was 80.0%. There were no significant reported complications noted in these studies.

CONCLUSION

After 15 years of presence, the expansion sphincter pharyngoplasty has shown to be reliably effective in the management of patients with OSA.

Does nasal surgery improve multilevel surgical outcome in obstructive sleep apnea: A multicenter study on 735 patients

OBJECTIVE

Does nasal surgery affect multilevel surgical success outcome.

METHODS

Prospective eight country nonrandomized trial of 735 obstructive sleep apnea (OSA) patients, who had multilevel palate and/or tongue surgery, divided into two groups, with or without nose surgery.

RESULTS

There were 575 patients in nose group, 160 patients in no nose group. The mean age for nose group 44.6 ± 11.4, no nose group 44.2 ± 11.8. Mean preoperative BMI for nose group 27.5 ± 3.6, no nose group 27.5 ± 4.1, mean postoperative BMI nose group 26.3 ± 3.7, no nose group 27.1 ± 3.8 (P = .006). Mean preoperative AHI nose group 32.7 ± 19.4, no nose group 34.3 ± 25.0 (P = .377); and mean postoperative AHI nose group 13.5 ± 10.2, no nose group 17.1 ± 16.0 (P = .001). Mean preoperative ESS nose group was 11.3 ± 4.7, no nose group was 10.4 ± 5.4 (P = .051); and mean postoperative ESS nose group was 5.3 ± 3.2, no nose group was 6.7 ± 2.8 (P = .001). The nose group had higher percentage change (adjusted for age, gender, BMI) in AHI (33.7%, 95% CI 14% to 53.5%) compared to the no nose group (P = .001); the nose group also had more percentage change in ESS (37%, 95% CI 23.6% to 50.3%) compared to the no nose group (P < .001). Change in BMI did not affect AHI nor ESS change (Cohen effect 0.03 and 0.14, respectively). AHI change in both groups were also statistically significant in the mild OSA (P = .008) and the severe OSA (P = .01). Success rate of surgery for the nose group 68.2%, while the no nose group 55.0% (P = .002).

CONCLUSION

Combining nose surgery in multilevel surgery improves surgical success.

LEVEL OF EVIDENCE

IIC.

SLEEP-GOAL: A multicenter success criteria outcome study on 302 obstructive sleep apnoea (OSA) patients

OBJECTIVE

To demonstrate SLEEP-GOAL as a more holistic and comprehensive success criterion for Obstructive Sleep Apnoea (OSA) treatment.

METHODS

A prospective 7-country clinical trial of 302 OSA patients, who met the selection criteria, and underwent nose, palate and/or tongue surgery. Pre- and post-operative data were recorded and analysed based on both the Sher criteria (apnoea hypopnea index, AHI reduction 50% and <20) and the SLEEP-GOAL.

RESULTS

There were 229 males and 73 females, mean age of 42.4±17.3 years, mean BMI 27.9±4.2. The mean VAS score improved from 7.7±1.4 to 2.5±1.7 (p<0.05), mean Epworth score (ESS) improved from 12.2±4.6 to 4.9±2.8 (p<0.05), mean body mass index (BMI) decreased from 27.9±4.2 to 26.1±3.7 (p>0.05), gross weight decreased from 81.9±14.3kg to 76.6±13.3kg. The mean AHI decreased 33.4±18.9 to 14.6±11.0 (p<0.05), mean lowest oxygen saturation (LSAT) improved 79.4±9.2% to 86.9±5.9% (p<0.05), and mean duration of oxygen <90% decreased from 32.6±8.9 minutes to 7.3±2.1 minutes (p<0.05). The overall success rate (302 patients) based on the Sher criteria was 66.2%. Crosstabulation of respective major/minor criteria fulfilment, based on fulfilment of two major and two minor or better, the success rate (based on SLEEP-GOAL) was 69.8%. Based solely on the Sher criteria, 63 patients who had significant blood pressure reduction, 29 patients who had BMI reduction and 66 patients who had clinically significant decrease in duration of oxygen <90% would have been misclassified as "failures".

CONCLUSION

AHI as a single parameter is unreliable. Assessing true success outcomes of OSA treatment, requires comprehensive and holistic parameters, reflecting true end-organ injury/function; the SLEEP-GOAL meets these requirements.

Long-term Complications of Palate Surgery: A Multicenter Study of 217 Patients

OBJECTIVES/HYPOTHESIS

To investigate long-term complications of newer reconstructive palate surgery techniques.

STUDY DESIGN

Retrospective case-series analysis.

METHODS

Retrospective six-country clinical study of OSA patients who had nose and palate surgery.

RESULTS

There were 217 patients, mean age = 43.9 ± 12.5 years, mean body mass index = 25.9 ± 4.7, mean preoperative apnea-hypopnea index [AHI] = 30.5 ± 19.1, follow-up 41.3 months. A total of 217 palatal procedures were performed, including 50 expansion sphincter pharyngoplasties (ESP), 34 functional expansion pharyngoplasties (FEP), 40 barbed reposition pharyngoplasties (BRP), 64 modified uvulopalatopharyngoplasties (mUPPP), 11 uvulopalatal flap procedures (UPF), nine suspension pharyngoplasties (SP), eight relocation pharyngoplasties (RP), and one z-pharyngoplasty (ZPP). Complications included were constant and/or felt twice per week; dry throat (7.8%), throat lump feeling (11.5%), throat phlegm (10.1%), throat scar feeling (3.7%), and difficulty swallowing (0.5%). Of the 17 patients who had a dry throat complaint, two were constant (one SP, one RP), 15 were occasional (10 mUPPP, three SP, two BRP). Of the 25 patients with the throat lump feeling, four were constant (three RP, one ZPP), 21 were occasional (10 mUPPP, five SP, five UPF, one BRP). Of the 22 patients with the throat phlegm feeling, four were constant (two SP, two RP), 18 were occasional (10 mUPPP, four BRP, two FEP, two SP). Of the eight patients with throat scar feeling, eight were occasional (four SP, two mUPPP, one FEP, one RP), none were constant. One patient had difficulty swallowing (RP procedure). There was no velopharyngeal incompetence, taste disturbance, nor voice change. Highest symptom complaints were mUPPP, SP, and RP, whereas the lowest symptom complaint was ESP.

CONCLUSIONS

Newer palatal techniques have shown to have less long-term complications compared to the older ablative techniques.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:2281-2284, 2020.

Does drug-induced sleep endoscopy affect surgical outcome? A multicenter study of 326 obstructive sleep apnea patients

OBJECTIVES/HYPOTHESIS

Our objective was to determine whether drug-induced sleep apnea (DISE) affects the successfulness of the surgical outcome.

STUDY DESIGN

Prospective, seven-country, nonrandomized trial.

METHODS

There were 326 consecutive obstructive sleep apnea (OSA) patients who had nose, palate, and/or tongue surgery included in the study. DISE was performed in only one group.

RESULTS

There were 170 patients in the DISE group and 156 patients in no-DISE group. The mean preoperative body mass index (BMI) for the DISE group was 27.6 ± 4.6, whereas in the no-DISE group it was 28.1 ± 3.9 (P = .23). The mean preoperative systolic blood pressure (SBP) for the DISE group was 130.4 ± 16.7, whereas in the no-DISE group it was 142.9 ± 15.5 (P < .001). The mean preoperative diastolic blood pressure (DBP) for the DISE group was 81.4 ± 9.7, whereas in the no-DISE group it was 89.1 ± 9.7 (P < .001). The mean preoperative apnea-hypopnea index (AHI) for the DISE group was 32.6 ± 18.8, whereas in the no-DISE group it was 33.7 ± 19.6 (P = .61). The mean postoperative AHI for the DISE group was 15.9 ± 12.6, whereas in the no-DISE group it was 13.2 ± 8.8 (P = .023). The age-, gender-, BMI-adjusted percentage change in AHI for the DISE group was -48.4 ± 31.9, whereas in the no-DISE group it was -59.8 ± 18.6 (P < .001). The age-, gender-, and BMI-adjusted success rate for the DISE group was 66.5%, whereas in the no-DISE group it was 80.8% (P = .004). The age-, gender-, and BMI-adjusted change in SBP for the DISE group was -6.1 ± 8.6, whereas in the no-DISE group it was -13.3 ± 11.1 (P < .001). The age-, gender-, and BMI-adjusted change in DBP in the DISE group was -5.2 ± 12.1, whereas in the no-DISE group it was -12.4 ± 11.7 (P < .001). The mean age- and gender-adjusted change in BMI for the DISE group was -4.6 ± 12.9, whereas in the no-DISE group it was -6.3 ± 18.5 (P = .34). The Cohen effect of BMI on the overall AHI, lowest oxygen saturation, and blood pressure changes was 0.08.

CONCLUSIONS

DISE may not significantly affect surgical success in OSA.

LEVEL OF EVIDENCE

2c Laryngoscope, 130:551-555, 2020.

Predictors of difficulty in intubation in patients with obstructive sleep apnoea

OBJECTIVE

To evaluate predictors of difficult intubation in patients with obstructive sleep apnoea (OSA).

METHODOLOGY

Prospective series of 405 OSA patients (350 males/55 females) who had upper airway surgery. Procedures included functional endoscopic sinus surgery, septoplasty, turbinate reduction, palate/tonsil surgery, and/or tongue base surgery. Intubation difficulty (ID) was assessed using Mallampati grade, Laryngoscopic grade (Cormack and Lehane), and clinical parameters including BMI, neck circumference, thyromental distance, jaw adequacy, neck movements and glidescope grading.

RESULTS

Mean age was 41.6 years old; mean BMI 26.6; mean neck circumference 44.5cm; mean Apnea Hypopnea Index (AHI) was 25.0; and mean LSAT 82%. The various laryngeal grades (based on Cormack and Lehane), grade 1 - 53 patients (12.9%), grade 2A - 127 patients (31.0%), grade 2B - 125 patients (30.5%), grade 3 - 93 patients (22.7%) and grade 4 - seven patients (1.7%); hence, 24.4% had difficulties in intubation. Parameters that adversely affected intubation were, age of the patient, opening of mouth, retrognathia, overbite, overjet, limited neck extension, thyromental distance, Mallampati grade, and macroglossia (p<0.001). Body mass index (BMI) (p=0.087), neck circumference (p=0.645), neck aches (p=0.728), jaw aches (p=0.417), tonsil size (p=0.048), and AHI (p=0.047) had poor correlation with intubation. BMI-adjusted for Asians and Caucasians, showed that Asians were more likely to have difficulties in intubation (adjusted OR = 4.6 (95%Confidence Interval: 1.05 to 20.06) (p=0.043), compared to the Caucasian group.

CONCLUSION

This study illustrates that difficult intubation can be predicted pre-surgery in order to avert any anaesthetic morbidity.

Prospective multi-center study on expansion sphincter pharyngoplasty

BACKGROUND AND OBJECTIVE

The aim of this study was to demonstrate the long-term effectiveness of Expansion Sphincter Pharyngoplasty (ESP) as a standalone surgical treatment of obstructive sleep apnea-hypopnea syndrome (OSAHS) patients through a prospective multi-center study.

MATERIAL AND METHODS

A prospective non-comparative multicenter study of patients suffering from OSHAS selected after drug-induced sleep endoscopy, with ESP as standing alone procedure was performed. Inclusion criteria were lateral collapse on oropharynx and preoperative AHI between 5 and 70. Minimum follow-up was >12 months. Outcome measures were Epworth sleepiness scale (ESS), AHI, success rate and CPAP need after surgery.

RESULTS

A total of 75 ESP were performed. Mean patient age was 46.7 ± 10.5 years. Mean pre-operative and post-operative AHI was 22.1 ± 12.2 and 8.6 ± 6.7, respectively (p < .001). Mean pre-operative and post-operative ESS score was 11.5 ± 4.7 and 4.6 ± 6.6, respectively (p < .001). AHI <5 was obtained in 25 patients (33.3%), and CPAP was not further needed after surgery in a total of 62 patients (82.6%).

CONCLUSIONS AND SIGNIFICANCE

In this prospective multi-center study, patients undergoing ESP standing alone for the treatment of OSAHS have a reasonable expectation for success with minimal morbidity.

Lingual tonsil lymphatic tissue regrowth in patients undergoing transoral robotic surgery

OBJECTIVES/HYPOTHESIS

To evaluate a possible regrowth of lingual tonsil lymphatic tissue in patients submitted to lingual tonsil resection with transoral robotic surgery (TORS).

STUDY DESIGN

Retrospective Study.

METHODS

Medical records of patients surgically treated by means of TORS to remove excessive lymphatic tissue of the lingual tonsil were retrospectively reviewed. Postoperative endoscopic data after long-term follow-up were analyzed to investigate possible lymphatic tissue regrowth. Preoperative and postoperative lingual tonsil lymphatic tissue were classified according to the standardized Friedman's grading scale ranging from 0 to 4.

RESULTS

Sixty-eight patients (41 male and 27 female; mean age = 51.3 years) were considered suitable for the study analysis. Clinical regrowth was observed in six (8.8%) patients: four (5.9%) and two (2.9%) patients with grade 2 and 3 lymphatic hypertrophy, respectively. No correlation between the grade of regrowth, the time interval from surgery, and the volume of lymphatic tissue removed was found.

CONCLUSIONS

The lymphatic tissue regrowth after TORS resection appears to be very low.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:2652-2657, 2019.

Anterior palatoplasty in the treatment of obstructive sleep apnoea - a systemic review

This study seeks to determine the objective and subjective success rates of anterior palatoplasty and its variants for the treatment of obstructive sleep apnoea (OSA). A systematic review with two independent searches of Medline, PubMed, Cochrane Library and Evidence Based Medicine Reviews was performed to identify publications relevant to OSA and anterior palatoplasty. All relevant studies published before 30 June 2015 were included. Six studies were included in the systematic review. The numbers of patients in each paper ranged from 13 to 77 (total = 240), and mean age ranged from 21 to 51 years. Substantial and consistent improvement in polysomnography (PSG) outcomes were observed in patients after the anterior palatoplasty, with or without multilevel surgery. The results showed that the anterior palatoplasty technique provides significantly improvement in the post-operative Apnoea-Hypopnea Index. The mean pre-operative AHI (in the 6 papers) improved from 16.3 to 7.1, the snore visual analogue scale improved from 7.5 to 3.1 and the Epworth score reduced from 11.3 to 7.3 post-operatively. The overall pro-rated pooled success rate for all the patients was 72.5%, with a mean follow-up of 17.3 months. Anterior palatoplasty is an effective option in the management of patients with mild to moderate OSA.

Upper airway surgery for obstructive sleep apnea reduces blood pressure

OBJECTIVES/HYPOTHESIS

To evaluate if upper airway surgery reduces blood pressure in patients with obstructive sleep apnea (OSA).

STUDY DESIGN

Prospective series.

METHODS

A prospective series of 112 consecutive OSA patients with hypertension (HTN). All patients were > 18 years old, respiratory disturbance index >5, all levels of apnea-hypopnea index (AHI), with a history of HTN treated with medication for at least 6 months. Surgical procedures included septoplasty, turbinate reduction, palate surgery, and tongue base reduction.

RESULTS

There were 92 men and 20 women, with a mean age of 48.6 years, mean body mass index (BMI) was 27.5 (range, 19.7-34.7). Mean follow-up was 16.1 months. The mean preoperative AHI was 32.6 (range, 1.2-104), with the mean lowest oxygen saturation (LSAT) of 79.9% (range, 52%-93%). The mean adjusted preoperative and postoperative systolic blood pressure (SBP) was reduced from 146 ± 15.3 mm Hg to 122 ± 12.5 mm Hg (P < .001), and diastolic blood pressure (DBP) was reduced from 91 ± 10.2 mm Hg to 76 ± 7.8 mm Hg (P < .001). There was a decrease in overall BMI from 27.5 ± 3.6 to 25.5 ± 3.0 (P < .001); however, based on multivariate analysis, the reduction in SBP and DBP was not affected by this BMI reduction. Fifty-eight patients (51.8%) did not require their antihypertensive after surgery. There was poor correlation noted between HTN with AHI, LSAT, and oxygen duration <90%.

CONCLUSIONS

Upper airway surgery does reduce SBP and DBP in patients with OSA.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:523-527, 2018.

Food allergy and allergic rhinitis in 435 asian patients - A descriptive review

OBJECTIVE

To describe the prevalence of food allergy in Asian patients with allergic rhinitis.

STUDY DESIGN

A non-randomized prospectively collected patients over a three year period, with complaints of nose congestion, rhinorrhea and/or nasal discharge.

RESULTS

There were 435 patients enrolled, 213 children and 222 adults. The children group had a high prevalence of allergen specific IgE to Dermatophagoides pteryonysinus (70%), Dermatophagoides farina (69%), and Blomia tropicalis (55%); followed by dogs (32%), cats (19%) and cockroaches (19%). In the children food allergy category, the top three allergens were egg white (54%), milk (31%) and soya bean (13%). The adult group had results of Dermatophagoides pteryonysinus (71%), Dermatophagoides farina (72%), and Blomia tropicalis (59%); the adult food allergy category, the top 3 allergens were egg white (13%), milk (6%) and soya bean (5%). There was a statistically significant difference in the child and adult group for Dust, D. pteryonysinus, D. farina, B.tropicalis, egg white, wheat, gluten and soya bean. In the age specific child groups, there was an increased in egg food allergy levels, with a peak at the age of five-nine years old and decreasing thereafter (p=0.04). In the children group, the mean Total Nasal Symptom Score (TNSS) was 10.3 (range of 7 to 13); the adult group was similar, with a mean TNSS of 9.8 (range 5 to 12).

CONCLUSION

The prevalence of food allergy in paediatric patients with allergic rhinitis is fairly high and should be considered when treating these children.

[Regulatory analysis of hypoxia on innate immunity of human corneal epithelium]

Objective: To investigate the role of hypoxia on the regulation of innate immunity of human corneal epithelium. Methods: Telomerase-immortalized human epithelial cells (THCEs) were incubated under normoxia (21% O₂) or hypoxic (1% O₂) conditions respectively. After 6, 12, 24, 48 h culture, the mRNA and protein levels of toll like receptor 4 (TLR4) were measured by real-time polymerase chain reaction (RT-PCR) and Western blot analysis. After 24 h culture, THCEs of each group were challenged respectively with TLR4 ligand lipopolysaccharide (LPS) (1 μg/ml) for 6 h. RT-PCR was used to assess the mRNA level of myeloid differentiation factor 88 (MyD88), interleukin(IL)6, IL-8 and tumor necrosis factor α (TNF-α). Western blot was used to examine the protein level of inhibitor of nuclear factor kappa-B α (IκBα) and phosphorylated IκBα (p-IκBα). Enzyme-linked immunosorbent assay (ELISA) was used to detect the secretion of the inflammatory cytokines IL-6, IL-8 and TNF-α. Results: The results of RT-PCR and Western blot analysis showed that the expression of TLR4 downregulated 90% and 55% respectively after hypoxic exposure for 48 h. Hypoxia also inhibited LPS-induced secretion of IL-6, IL-8, TNF-α, expression of MyD88 and activation of NF-κB. The mRNA level of MyD88 was diminished 63%, and the protein expression of p-IκBα was also lowered. Meanwhile, the secretions of IL-6, IL-8 and TNF-α under hypoxia were reduced (31%, 55% and 50% respectively). Conclusion: Hypoxia attenuated immune and inflammatory response of the cornea epithelium by suppressing TLR4 signaling, and could enhance cell susceptibility to microorganism infection.

[Study on the susceptibility of human corneal epithelial cells to Acanthamoeba in a hypoxia condition]

Objective: To investigate the regulation mechanism of Acanthamoeba-induced immune responses of human corneal epithelial cells in a hypoxia condition. Methods: Telomerase-immortalized human epithelial cells (THCEs) challenged with Acanthamoeba (1×10⁶/ml) were incubated under normoxic (21% O₂) (control group) or hypoxic (1% O₂) (experiment group) conditions respectively. The mRNA of toll-like receptor (TLR4), myeloid differentiation factor 88 (MyD88), nuclear factor kappa-B (NF-κB), tumor necrosis factor-α (TNF-α), interleukin-8 (IL-8), interferon-β (IFN-β), and the protein level of TLR4, inhibitor of nuclear factor kappa-Bα (IκBα), phosphorylated extracellular-signal related kinase 1/2 (p-ERK1/2) and phosphorylated IκBα (p-IκBα) were detected. Enzyme-linked immunosorbent assay (ELISA) was used to detect the secretion of the inflammatory cytokines (TNF-α, IL-8 and IFN-β). Results: The mRNA levels of Acanthamoeba-induced TLR4, MyD88, NF-κB, TNF-α, IFN-β and IL-8 in THCEs under hypoxia was down-regulated by 47%, 41%, 45%, 53%, 36% and 50% respectively, compared to control group. And the protein levels of p-IκBα and p-ERK1/2 were significantly down-regulated by 56% and 55%, respectively, while the protein expression of IκBα was increased. The secretions of TNF-α, IL-8 and IFN-β under hypoxia were reduced by 46%, 28% and 35%, respectively. Conclusion: Hypoxia might attenuated the inflammatory response of the human corneal epithelial cells against Acanthamoeba infection by suppressing TLR4 signaling.

Combined Expansion Pharyngoplasty and Anterior Palatoplasty for the Treatment of OSA

To evaluate the success rates of combined Expansion Sphincter Pharyngoplasty and the Anterior Palatoplasty in the treatment of OSA. A two center prospective series of 73 patients with OSA. All patients were >18 years old, retro-palatal obstruction, concentric velo-pharyngeal collapse, BMI < 33, Friedman clinical stage II, with all grades of AHI. The procedure involved the anterior palatoplasty, tonsillectomy and expansion sphincter pharyngoplasty with or without nasal surgery. There were 68 men and 5 women, the mean age was 46.8 years old (range of 25-67 years), mean BMI was 25.5 (range of 20.3-31.2). All patients had pre-operative and post-operative PSG. The AHI improved in all patients, mean AHI improved from 26.3 ± 17.7 to 12.6 ± 5.8 (p < 0.001). There were 20 mild OSA, 33 moderate OSA and 20 severe OSA patients. Twenty-three patients had pre-operative DISE, and 61 patients had nose/palate surgery, while only 12 had palate surgery alone. The overall success rate (50 % reduction and AHI < 20) was 86.3 %. The mean snore scores (VAS) improved from 8.8 ± 1.2 to 2.0 ± 1.3 (p < 0.001). The mean Epworth score improved from 11.5 ± 2.2 to 2.9 ± 2.1 (p < 0.001). Lowest oxygen saturation also improved in all patients. Subjectively, all the patients felt less tiredness. Pre-operative DISE assessment did not seem to confer any advantage over the patients who had no pre-operative DISE (p = 0.027), and patients who had nose/palate surgery seemed to have better success rates compared to those who only had palate surgery (p = 0.081). This combined technique has been shown to be effective in selected group of OSA patients. Level of evidence IV.

Trends in CPAP adherence over twenty years of data collection: a flattened curve

Background

Obstructive sleep apnea (OSA) is a common disorder, and continuous airway positive pressure (CPAP) is considered to be the gold standard of therapy. CPAP however is known to have problems with adherence, with many patients eventually abandoning the device. The purpose of this paper is to assess secular trends in CPAP adherence over the long term to see if there have been meaningful improvements in adherence in light of the multiple interventions proposed to do so.

Methods

A comprehensive systematic literature review was conducted using the Medline-Ovid, Embase, and Pubmed databases, searching for data regarding CPAP adherence over a twenty year timeframe (1994–2015). Data was assessed for quality and then extracted. The main outcome measure was reported CPAP non-adherence. Secondary outcomes included changes in CPAP non-adherence when comparing short versus long-term, and changes in terms of behavioral counseling.

Results

Eighty-two papers met study inclusion/exclusion criteria. The overall CPAP non-adherence rate based on a 7-h/night sleep time that was reported in studies conducted over the twenty year time frame was 34.1 %. There was no significant improvement over the time frame. Behavioral intervention improved adherence rates by ~1 h per night on average.

Conclusions

The rate of CPAP adherence remains persistently low over twenty years worth of reported data. No clinically significant improvement in CPAP adherence was seen even in recent years despite efforts toward behavioral intervention and patient coaching. This low rate of adherence is problematic, and calls into question the concept of CPAP as gold-standard of therapy for OSA.

Pediatric Tracheotomies in an Asian Population: The Singapore Experience

Objective:

Over the past 2 decades, tracheotomy in children and infants has evolved from a primarily emergent procedure for upper airway obstruction into a semielective procedure for airway access in assisted ventilation. We present a 12-year retrospective review of tracheotomies performed in the pediatric population in Singapore.

Study Design and Setting:

We reviewed all tracheotomies performed in children below the age of 16 years in 2 tertiary pediatric medical centers in Singapore from January 1991 to December 2003. Indications for surgery are reviewed, and outcomes in terms of morbidity rate, mortality rate, postoperative rehabilitation, and duration of decannulation process were analyzed.

Results:

Tracheotomies were performed in 48 children during the study period. The mean age of patients was 3.24 years, with ages ranging from 16 days to 14 years. Sixty-three percent of tracheotomies were done within the 1st year of life. The chief indication was airway access for assisted ventilation. The overall complication rate was 31%. There were 13 attempts at decannulation, with 9 successes. No tracheotomy-related deaths occurred.

Conclusion:

Tracheotomy is a relatively safe procedure in children and infants. Lower decannulation rates and the evolving role of tracheotomy for early access in assisted ventilation permits earlier discharge with tracheotomy in situ.

Reconsidering first-line treatment for obstructive sleep apnea: a systematic review of the literature

BACKGROUND

Continuous positive airway pressure (CPAP) is typically recommended as first line therapy for obstructive sleep apnea, but the adherence rate of CPAP is problematic. This study's objective was to systematically review the literature relating to CPAP as first line therapy for OSA and compare it to surgical literature on the same topic.

METHODS

A systematic review was conducted according to PRISMA guidelines, examining Medline-Ovid, Embase, and Pubmed databases. The primary search objective was to identify all papers reporting the results of (1) randomized clinical trials (RCT) of CPAP for the treatment of adults with OSA; and (2) both randomized and non-randomized clinical trials and case series on the surgical treatment of OSA in adults. A PhD-level biostatistician first screened papers, and then those that met study criteria were retrieved and analyzed using standardized forms for each author. The primary outcomes were adherence rates of CPAP.

RESULTS

A total of 82 controlled clinical trials for CPAP and 69 controlled and non-controlled surgery trials were identified for analysis. Variation in CPAP use within reported RCT trials were identified, and the majority of patients in the studies would eventually be considered non-adherent to CPAP.

CONCLUSIONS

When considering the numerous patient-related factors that come into play when CPAP is prescribed, the concept of CPAP as gold-standard therapy for OSA should be reconsidered. In many cases surgery can provide a better overall outcome. This study's results suggest that certain patients with OSA may be managed more effectively with surgery than CPAP, without confounding issues of treatment adherence.

Expansion sphincter pharyngoplasty for the treatment of OSA: a systemic review and meta-analysis

This study seeks to determine the success rates of the expansion sphincter pharyngoplasty and its variants on the treatment of obstructive sleep apnea (OSA). Systematic review and meta-analysis. Two independent searches of MEDLINE, Google Scholar, Cochrane Library and Evidence Based Medicine Reviews to identify publications relevant to OSA and expansion pharyngoplasty. All relevant studies published before 31 March 2015 were included. Five studies were included in the systematic review and meta-analysis. The numbers of patients in each paper ranged from 10 to 85 (total = 155), and mean age ranged from 8 to 56 years. Substantial and consistent improvement in PSG outcomes were observed post-expansion pharyngoplasty patients, with or without multilevel surgery groups. The results showed that the expansion pharyngoplasty technique has significantly lower AHI than control group [Standardised mean difference -7.32, 95 %CI (-11.11, -3.52), p = 0.0002]; however, substantial heterogeneity between these studies were observed. The mean pre-operative AHI (in the five papers) improved from 40.0 ± 12.6 to 8.3 ± 5.2 post-operatively. The overall pro-rated pooled success rate for all the patients was 86.3 %. The expansion pharyngoplasty is effective in the management of patients with OSA.

A case of ear canal black pigment foreign body mimicking a melanoma

Melanoma of the ear canal is extremely rare; due to its hidden area, most would present late in their history. We present the first case reported, of a black pigment foreign body mimicking a melanoma in the external auditory canal. A 14 year old Chinese male presented with right sided otalgia and itch. Otoscopic examination revealed an irregular black naevus in the right auditory canal. An intraoperative excision showed a black pigment foreign body giant cell reaction. Clinicians should be aware of the possibility of a foreign body granuloma of the ear canal that might mimic a melanoma.

Pang-Rotenberg sign--snoring surgery prognosticator: A prospective clinical trial of 153 patients

OBJECTIVES/HYPOTHESIS

To illustrate the reliability of the Pang-Rotenberg (PR) sign as a prognosticator of snoring surgery. Our hypothesis was that patients who are PR-positive have better snoring reduction scores and outcomes than PR-negative patients after nose and palate surgery.

STUDY DESIGN

A multicenter prospective series of 153 patients with snoring.

METHODS

All patients graded the snoring intensity on a visual analog scale (VAS). All 137 patients enrolled had both the nose surgery and palate surgery. The control group consisted of 16 patients who underwent nasal surgery alone.

RESULTS

There were 122 men and 15 women, the mean age was 44.6 years old, and mean body mass index was 26.1. There were 15 simple snorers and 122 obstructive sleep apnea patients. Patients who were PR-positive showed significantly better postoperative snoring VAS reduction (from 9.04 to 1.02) compared to those patients who were PR-negative (from 8.91 to 3.14) (P < .001). The mean follow-up time was 7.4 months. The control group had poor snoring VAS reduction from 9.21 to 6.72. After adjusting for covariates that influence the snoring VAS change due to surgery, we found that PR-negative patients achieved an average of 5.78 improvement in snoring VAS, whereas PR-positive patients achieved an average of 8.02 improvement in snoring VAS (P < .001).

CONCLUSIONS

The PR sign is a reliable prognosticator of snoring reduction, after combined nose and palate surgery, for patients with troublesome snoring.

Current Concepts and Pitfalls in the Management of Obstructive Sleep Apnea

Program Description:

There are many different ways and surgical techniques available to treat OSA, causing a lot of confusion and disparity in managing these OSA patients. There is a need to standardize diagnosis, treatment, and prognosis. Concepts will be discussed and pitfalls will be highlighted. This miniseminar will address these latest current concepts in airway evaluation, clinical diagnosis, polysomnographic diagnosis, and various surgical management (from nose, palate, and tongue surgery). The miniseminar will also highlight the pitfalls that should be avoided in the management of OSA.

Educational Objectives:

1) Recognize the basic concepts of airway evaluation and diagnosis and surgical management of OSA. 2) Confidently diagnose, evaluate, and treat patients with OSA.

Palate Surgery in Obstructive Sleep Apnea: How to Choose among the Options

Program Description:

Palate surgery is the primary surgical approach for treatment of OSA. Although uvulopalatopharyngoplasty (UPPP) was described 30 years ago, the past 10-15 years have witnessed the development of alternative palatoplasty techniques. This miniseminar draws from leading surgeons who have developed these procedures and/or performed clinical trials related to them. Findings from published studies will enable attendees to learn more about selection from among the procedures for their patients.

Educational Objectives:

1) Interpret evidence regarding the range of palatoplasty techniques: UPPP, palate stiffening, modified expansion sphincter pharyngoplasty, relocation pharyngoplasty, lateral pharyngoplasty, Z-palatoplasty, and palatal advancement. 2) Differentiate between the various palatoplasty techniques for different types of patients.

Safety of multilevel surgery in obstructive sleep apnea: a review of 487 cases

OBJECTIVE

To review the safety of multilevel surgery in patients with obstructive sleep apnea (OSA).

DESIGN

Retrospective review.

PATIENTS

A total of 487 consecutive patients with OSA and 1698 surgical procedures from January 2007 to May 2010.

INTERVENTIONS

Multilevel OSA surgery comprising nasal surgery (endoscopic sinus surgery, septoplasty, and inferior turbinate reduction), palate surgery (traditional uvulopalatopharyngoplasty, expansion sphincter pharyngoplasty and anterior palatoplasty), and tongue surgery (hyoid suspension, radiofrequency tongue base, and tongue suspension suture).

MAIN OUTCOME MEASURES

Surgical complications.

RESULTS

The overall complication rate was 7.1%, with 1 patient having an upper airway obstruction. Complications were as follows: (1) 6 patients had postoperative oxygen desaturation within 3 hours after extubation (these patients had severe OSA [apnea-hypopnea index > 60 and lowest oxygen saturation level <80%]), (2) 15 patients had persistent hypertension (these patients had a history of hypertension), (3) 15 patients had secondary hemorrhage (7-12 days postoperatively), (4) there were 2 cases of negative pressure pulmonary edema, (5) 9 patients had tongue edema (following tongue surgery), and (6) 1 patient had upper airway obstruction requiring reintubation. Patients who had undergone tongue surgery were admitted routinely to the high-dependency unit (step-down care from the intensive care unit) overnight.

CONCLUSIONS

Routine postoperative admission to the intensive care unit for all patients with OSA is unnecessary. These patients should be closely monitored in the postanesthesia care unit area after surgery, and based on the outcome of this period, they can be observed overnight in either the high-dependency unit or the general ward.

Current Concepts in Tongue Surgery for OSA

Program Description: To describe the various tongue base surgical techniques that are available for patients with OSA. Why we do them, who we do them for, and when? Tongue base obstruction has been known to be one of the levels of obstruction in OSA. Surgical treatment of the palate alone has been shown to be ineffective in patients with high Mallampati grades, Friedman Stage II & III, and tongue base collapse seen on dynamic nasopharyngoscopy. Severity of OSA is currently known to correlate with degree of tongue base and lateral pharyngeal wall collapse. Patients with severe OSA are more likely to have tongue base obstruction. Airway evaluation is vital in the management and assessment of patients with OSA. The indications for tongue base surgery is pivotal in the decision making process. All the indications based on the clinical examination would be explored and discussed. Various tongue base surgical techniques are discussed, ranging from radiofrequency of the tongue base, genioglossus advancement, hyoid suspension, laser midline glossectomy, tongue suspension, coblator channeling techniques, and robotic tongue base surgery. The surgical steps are illustrated, success rates are presented, and complications are discussed.

Educational Objectives: 1) Apply the appropriate airway evaluation. 2) Choose the correct procedure. 3) Understand the technique behind each procedure.

Anterior palatoplasty for the treatment of OSA: three-year results

OBJECTIVE

Review long-term results of the modified cautery-assisted palatoplasty (mod CAPSO)/anterior palatoplasty for the treatment of mild-moderate obstructive sleep apnea (OSA).

STUDY DESIGN

Prospective series of 77 patients. All patients were >18 years old, type I Fujita, body mass index (BMI)<33, Friedman clinical stage II, with apnea-hypopnea index (AHI) from 1.0 to 30.0. The mean follow-up time was 33.5 months. The procedure involved an anterior soft palatal advancement technique with or without removal of the tonsils. The procedure was done under general or local anesthesia.

RESULTS

There were 69 men and eight women; the mean age was 39.3 years old; and mean BMI was 24.9 (range 20.7-26.8). There were 38 snorers and 39 OSA patients. The AHI improved in patients with OSA, 25.3+/-12.6 to 11.0+/-9.9 (P<0.05). The overall success rate for this OSA group was 71.8 percent (at mean 33.5 months). The mean snore scores (visual analog score) improved from 8.4 to 2.5 (for all 77 patients). Lowest oxygen saturation also improved in all OSA patients. Subjectively, all patients felt less tired.

CONCLUSION

This technique has been shown to be effective in the management of patients with snoring and mild-moderate OSA.

Clinical parameters in obstructive sleep apnea: are there any correlations?

OBJECTIVE

To assess the correlation between clinical symptoms and examination findings with severity of obstructive sleep apnea (OSA).

DESIGN

Prospective observational study.

SETTING

Otorhinolaryngology sleep clinic in a tertiary referral centre.

PARTICIPANTS

Consecutive patients referred to the sleep clinic with a suspected diagnosis of OSA.

MAIN OUTCOMES MEASURES

Body mass index (BMI), Epworth Sleepiness Scale (ESS) score, tonsil size, modified Mallampati index (MMP), Müller manoeuvre, reflux finding score (RFS), apnea-hypopnea index (AHI), lowest oxygen saturation, and percentage of rapid eye movement sleep.

RESULTS

Eighty patients (14 female, 66 male), with a mean age of 42.9 years (range 22-66), were included in the study. The mean BMI was 27.6 (range 20-39). A correlation was found between ESS score and anteroposterior pharyngeal wall collapse at the level of the soft palate during Müller manoeuvre (r=.3, p=.02). BMI was significantly associated with a history of hypertension (r=.3, p=.01), MMP (r=.3, p=.001), and lateral wall collapse at the level of the soft palate during Müller manoeuvre (r=.4, p=.0001). OSA severity correlated significantly with male gender (p=.02), history of hypertension (r=.5, p<.0001), BMI (r=.2, p=.03), MMP (r=.3, p=.003), and upper airway collapse during Müller manoeuvre.

CONCLUSIONS

Clinical findings in patients with OSA do correlate with the severity of OSA and polysomnographic findings. The degree of upper airway collapse during Müller manoeuvre does correlate with AHI severity. Accuracy in predicting the presence and severity of OSA allows for greater cost-effectiveness in screening patients prior to polysomnography.

Haemangioma of the uvula causing loud habitual snoring--a rare entity

Mucosal haemangiomas are unusual and typically involve frequently traumatised areas such as the lip, buccal mucosa and lateral borders of the tongue. Uvular haemangioma is rare and to our knowledge, has never been reported to cause obstructive sleep apnoea (OSA). We report an unusual case of uvular haemangioma causing loud habitual snoring and symptoms suggestive of OSA. This case report illustrates a rare cause of OSA and demonstrates the efficacy of surgery for obvious obstructive lesions of the pharynx.

A comparison of polysomnography and the WatchPAT in the diagnosis of obstructive sleep apnea

OBJECTIVE

Our goal was to validate the WatchPAT in the diagnosis of obstructive sleep apnea.

STUDY DESIGN

We conducted a prospective, blinded, nonrandomized clinical trial.

METHODS

Patients with suspected obstructive sleep apnea scheduled for an overnight level I polysomnogram were offered enrollment in a study to compare the WatchPAT (Itamar Ltd, Israel) device with polysomnography. Patients wore the WatchPAT device simultaneously while undergoing polysomnography during evaluation in the sleep lab.

RESULTS

Thirty-seven patients participated in the study. They had a mean age of 50.1 years (range, 31-73 years) and mean body mass index of 34.6 kg/m(2) (range, 21.2-46.8 kg/m(2)). There was high correlation between the polysomnogram and WatchPAT apnea-hypopnea index (r = 0.9288; 95% confidence interval = 0.8579-0.9650, P < 0.0001). The lowest oxygen saturation also showed high correlation (r = 0.989; 95% confidence interval = 0.9773-0.9947, P < 0.0001). The overall polysomnogram and WatchPAT sleep times revealed a correlation of r = 0.5815 (P = 0.005).

CONCLUSION

The WatchPAT showed a high correlation with the polysomnogram in apnea-hypopnea index, lowest oxygen saturation, and sleep time.

SIGNIFICANCE

It's use as a reliable tool in the diagnosis of Obstructive Sleep Apnea.

Expansion sphincter pharyngoplasty: a new technique for the treatment of obstructive sleep apnea

OBJECTIVE

In this study, we assessed the efficacy of a new method (expansion sphincter pharyngoplasty [ESP]) to treat obstructive sleep apnea.

STUDY DESIGN

We conducted a prospective, randomized controlled trial.

METHODS

Forty-five adults with small tonsils, body mass index less than 30 kg/m2, of Friedman stage II or III, of type I Fujita, and with lateral pharyngeal wall collapse were selected for the study.

RESULTS

The mean body mass index was 28.7 kg/m2. The apnea-hypopnea index improved from 44.2 +/- 10.2 to 12.0 +/- 6.6 (P < 0.005) following ESP and from 38.1 +/- 6.46 to 19.6 +/- 7.9 in the uvulopalatopharyngoplasty group (P < 0.005). Lowest oxygen saturation improved from 78.4 +/- 8.52% to 85.2 +/- 5.1% in the ESP group (P = 0.003) and from 75.1 +/- 5.9% to 86.6 +/- 2.2% in the uvulopalatopharyngoplasty group (P < 0.005). Selecting a threshold of a 50% reduction in apnea-hypopnea index and apnea-hypopnea index less than 20, success was 82.6% in ESP compared with 68.1% in uvulopalatopharyngoplasty (P < 0.05).

CONCLUSION/SIGNIFICANCE

The ESP may offer benefits in a selected group of OSA patients.

Modified cautery-assisted palatal stiffening operation: new method for treating snoring and mild obstructive sleep apnea

OBJECTIVE

To assess a new method (modified cautery-assisted palatal stiffening operation [CAPSO]) to treat snoring and mild obstructive sleep apnea (OSA).

DESIGN

A prospective, nonrandomized trial.

METHODS

Thirteen patients with simple snoring and mild OSA underwent the modified CAPSO under local anaesthesia. All patients had preoperative polysomnography and at 3 months postoperatively.

RESULTS

All patients were Friedman stage II and III, with tonsil size 0, 1, or 2. All patients had improvement in their snoring. Eighty-four percent of the patients had improvement in the Epworth Sleepiness Scale, from 12.2 to 8.9. Objective success on the polysomnogram was noted in six out of the eight patients (75%) with mild OSA. The AHI improved from 12.3% to 5.2% (P < 0.05), and the LSAT improved from 88.3% to 92.5% (P < 0.05).

CONCLUSION

The modified CAPSO is a simple, low-cost, and effective office-based method to treat snoring and mild obstructive sleep apnea.

Severity of obstructive sleep apnea: correlation with clinical examination and patient perception

OBJECTIVE

To correlate clinical history, patient self-perception of obstructive sleep apnea, and physical examination with the severity of OSA.

METHODS

One hundred and two consecutive patients were prospectively enrolled over a 6-month period. All patients underwent a comprehensive history and clinical examination, nasopharyngoscopy, and an overnight-attended polysomnogram.

RESULTS

There were 65 males and 37 females with a mean age of 50.2 +/- 11.3 years (range, 24 to 76 years). The mean apnea-hypopnea index (AHI) was 37.9 +/- 27.7 (range, 0.7 to 111.2). There was a strong correlation between patient self-perception of OSA severity and AHI (r = 0.499, P < 0.0001), and the correlation with AI was 0.577 (P < 0.0001). OSA severity strongly correlated with Friedman Tongue Position grade, (r = 0.389, P < 0.0001), Friedman clinical staging, (r = 0.331, P = 0.0007). Of significance, only 6.9% of patients with mild OSA had a >50% collapse of the base of tongue region, as compared to 65.9% of patients with severe OSA.

CONCLUSION

There is good correlation between clinical examination parameters and the severity of OSA. An algorithm for surgical treatment of OSA should acknowledge both the site of obstruction and the severity of disease.

A comparison of polysomnography and the SleepStrip in the diagnosis of OSA

OBJECTIVE

To investigate the role of a portable screening device (SleepStrip) in the diagnosis of obstructive sleep apnea (OSA).

METHODS AND MATERIALS

Prospective, nonrandomized double-blinded single cohort study at an academic health center. Patients with suspected OSA scheduled for an attended overnight Level I polysomnogram (PSG) and who consented to participate in the study wore the SleepStrip device at home the night after the PSG. The apnea-hypopnea index (AHI) determined by PSG was compared with the results of the SleepStrip recording.

RESULTS

Thirty-seven patients with a mean age of 52.1 +/- 12.2 years and mean body mass index of 35.7 +/- 5.2 participated in the study. The overall agreement between the AHI and the SleepStrip results using Cohen's Kappa value was 0.139 (P = 0.19). The sensitivity and specificity of the SleepStrip for diagnosing severe OSA when the AHI was >40 were 33.3% and 95% (P = 0.05). When the AHI was >25, the SleepStrip sensitivity and specificity were 43.8% and 81.3% (P = 0.26). The sensitivity and specificity of the SleepStrip for diagnosing OSA in patients with an AHI >15 were 54.6% and 70%, respectively (P = 0.26).

CONCLUSION

The SleepStrip has a low correlation with the AHI as measured by PSG. Further studies are needed before this device can be recommended as a screening tool for the diagnosis of OSA.

EBM RATING

B-2b.

Identifying patients who need close monitoring during and after upper airway surgery for obstructive sleep apnoea

Potentially serious complications have been documented in patients undergoing upper airway surgery for obstructive sleep apnoea (OSA). Consensus is lacking regarding peri- and post-operative monitoring and identification of those patients likely to suffer post-operative complications. This retrospective review of 118 patients treated and 152 surgical procedures undertaken, from January 1998 to December 2003, addresses this issue. The overall peri- and post-operative complication rate was 13.8 per cent, with one patient experiencing upper airway compromise, five patients experiencing post-operative oxygen desaturation within 150 minutes of extubation, six patients experiencing persistent hypertension and four patients suffering secondary haemorrhage. All patients were treated accordingly and recovered well, with no mortality. From these results, it is concluded that patients with severe OSA (apnoea-hypopnoea index > 60 and lowest oxygen saturation < 80 per cent) are at higher risk of post-operative oxygen desaturation. Post-operative hypertension is more likely in patients with a prior history of hypertension. Routine post-operative admission to an intensive care unit for all OSA patients is unnecessary (including patients with severe OSA). However, all patients with OSA should be closely monitored in the post-anaesthesia care area for at least three hours after surgery; based on the outcome of this period and the clinical judgment of the clinician, the patient can then be observed overnight in either the high dependency unit or on a general ward. Patients with mild OSA may be admitted to the 23-hour ambulatory unit post-operatively. Use of continuous positive airway pressure in the immediate post-operative period can reduce the incidence of post-operative respiratory compromise and complications and is strongly recommended.