Eur Arch Otorhinolaryngol (2015) 272:407–412 DOI 10.1007/s00405-014-3344-4
LARYNGOLOGY
Reoperation on patients with obstructive sleep apnea–hypopnea syndrome after failed uvulopalatopharyngoplasty Shuhua Li • Dahai Wu • Hongjin Shi
Received: 18 June 2014 / Accepted: 16 October 2014 / Published online: 21 October 2014 Ó Springer-Verlag Berlin Heidelberg 2014
Abstract The goals of this study were to explore the reasons after failed uvulopalatopharyngoplasty (UPPP) in some patients with obstructive sleep apnea–hypopnea syndrome (OSAHS), and to observe the efficacy of the second surgery. Twenty-three OSAHS patients with failed UPPP were included in the study. Routine physical exams, electronic endoscopy, computed tomography scan and polysomnography after nasopharyngeal tube insertion were performed to assess the site of upper airway obstruction, and corresponding appropriate surgical treatment was carried out based on the diagnosis. Comprehensive evaluation of the 23 patients revealed that the sites of obstruction after failed UPPP were as follows: 7 cases predominantly in the oropharyngeal area, 2 cases in the nasal, nasopharyngeal and oropharyngeal area, 5 cases predominantly in the glossopharyngeal area and 9 cases in the oropharyngeal and glossopharyngeal areas. Correspondingly, 7 cases underwent improved UPPP alone, 2 cases underwent adenoidectomy or nasal expansion and improved UPPP, 5 cases underwent glossopharyngeal surgery alone and 9 cases underwent improved UPPP and glossopharyngeal surgery. Follow-up for more than 12 months showed that there were four cured cases, 12 cases with marked improvement, and 7 cases with treatment failure. The success rate was 69.6 %. After undergoing UPPP, OSAHS patients may still have oropharyngeal airway obstruction.
S. Li (&) D. Wu H. Shi Department of Otolaryngology-head and Neck Surgery, General Hospital of Shenyang Military Area Command, No.83, Wenhua Road, Shenhe District, Shenyang 110840, China e-mail: [email protected]
By performing a detailed preoperative assessment on the patient’s airway condition and clarifying the site of obstruction, performing the second surgical treatment can still achieve a relatively satisfactory treatment outcome. Keywords Obstructive sleep apnea–hypopnea syndrome Uvulopalatopharyngoplasty Failure Nasopharyngeal tube Reoperation
Introduction Obstructive sleep apnea hypopnea syndrome (OSAHS) refers to apnea and hypoventilation caused by upper airway collapse during sleep, accompanied by snoring, disrupted sleep structure, frequent occurrence of oxygen desaturation, daytime sleepiness and other symptoms [1]. The key to the occurrence of OSAHS is upper airway collapse or obstruction during sleep. In addition to continuous positive airway pressure (CPAP) therapy, surgery is also an effective method for treating OSAHS. As a basic surgery for the treatment of OSAHS, uvulopalatopharyngoplasty (UPPP) has been widely applied [2]. However, despite many improvements are made since the beginning of the application of UPPP for treating OSAHS, UPPP alone may still fail in some cases [3–5]. Subsequent treatment for patients after failed UPPP is necessary. If CPAP treatment cannot be tolerated or accepted by the patient, another surgical treatment has to be performed. In recent years, our group conducted assessment on the upper airway condition and site of obstruction for OSAHS patients in whom UPPP had failed, and re-performed surgical treatment based on the assessment results. The goals of this study were to explore the reasons after failed UPPP in some patients with OSAHS, and to observe the efficacy of the second surgery.
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408
Materials and methods
Eur Arch Otorhinolaryngol (2015) 272:407–412
Assessment on the site of upper airway obstruction and surgical treatment
Patient selection This study was approved by the ethics committee of the Medical Research Institute. All the patients were recruited from among the patients treated at the Department of Otorhinolaryngology Head and Neck Surgery from January 2010 to December 2012. Patient selection criteria were as follows: (1) having performed UPPP for treatment of OSAHS; (2) following up for more than 12 months after UPPP; (3) meeting a standard to reoperation based on a cut-off point of 20 times/h for apnea–hypopnea index (AHI); (4) no micrognathia and other abnormalities in craniofacial structure; (5) being unable or unwilling to accept CPAP treatment; (6) having a strong need for surgical treatment; and (7) having signed informed consent. Polysomnography (PSG) monitoring and upper respiratory tract examination The polywin PSG system (Respironics Inc., US) was used for sleep monitoring in all patients. PSG examinations were in accordance with American Sleep Association standards [6]. AHI and lowest oxygen saturation (LaSO2) during sleep were used as the main diagnostic indicators. Patients who were considered to require reoperation based on a cutoff point of 20 times/h for AHI were included, and LaSO2 was as a reference index. To assess the site of upper airway obstruction, all patients experienced a routine physical examination and other auxiliary examinations, including Friedman tongue position classification (FTP), upper respiratory tract computed tomography (CT) imaging, conventional electronic endoscopic examination, endoscopic observation of Muller action and PSG examination after nasopharyngeal tube insertion (NPT-PSG). FTP, CT scan and endoscopic examination were conducted with conventional methods [4, 7, 8]. NPT-PSG procedures were described shortly as follows [9–11]. The silicone nasopharyngeal tube (NPT) was selected based on nasal cavity anatomy. A tube with a 7-mm internal diameter (ID) was used in 10 patients, and 8-mm ID tubes were used in 13 patients. After one percent of ephedrine and dicaine were applied to shrink and anesthetize nasal cavity tissues, liquid paraffin was used to lubricate the surface of the NPT, which was gently inserted into the wider anterior nostril until the distal end of the tube was just beyond the free edge of the soft palate. The tube was secured to the anterior nostril with a drawstring to prevent it from moving during sleep. PSG was repeated after successful insertion of the NPT. The examination procedure and diagnostic indices were the same as in the first PSG.
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For assessment, the upper respiratory tract was divided into the following three parts: the nasal cavity-nasopharynx, oropharynx and glossopharynx. Evaluation of the nasal cavity-nasopharynx was primarily based on nasal endoscopy and CT scan results. Those with an obvious deviated nasal septum, turbinate hypertrophy, new growth in the nasal cavity or adenoid hypertrophy were considered to have nasal cavity-nasopharyngeal obstruction and appropriate surgical treatments were performed [12]. Evaluations of the oropharyngeal and glossopharyngeal areas were mainly based on NPT-PSG results. If NPT-PSG examination showed a 50 % reduction or greater in level of AHI compared to PSG result before NPT insertion and the AHI after NPT insertion was less than 15 times/h, it was assumed that there was no obvious obstruction in the glossopharyngeal area, and the obstruction was primarily located in the oropharyngeal area. In this case, improved UPPP [9, 10] was performed. Improved UPPP mainly involved further expansion of the pharyngeal cavity via removal of the part of the soft palate, uvula re-shaping and other means. If NPT-PSG revealed that AHI was greater than or equal to 15 times/h, the case was considered as obvious glossopharyngeal obstruction [9–11]. In particular, if the AHI determined by NPT-PSG was reduced less than 50 % compared to the first PSG, the obstruction was considered to be predominantly in the glossopharyngeal area and glossopharyngeal surgery was performed. If the AHI was reduced more than 50 %, it was assumed that obstructions were present in both oropharyngeal and glossopharyngeal areas, and improved UPPP along with glossopharyngeal surgery was performed. For patients with confirmed glossopharyngeal obstruction, Friedman tongue position, endoscopy and CT scan results were combined to determine the cause of the glossopharyngeal obstruction, and the appropriate surgical procedure was carried out accordingly. Patients with lingual tonsillar hypertrophy underwent lingual tonsillectomy and those with tongue hypertrophy underwent midline partial glossectomy [13]. Patients without obvious tongue hypertrophy or lingual tonsillar hyperplasia underwent tongue-base suspension (Repose surgery) [14]. Follow-up, efficacy evaluation and statistical analysis All patients underwent follow-up for more than 12 months, with an average follow-up time of 18 months. After 12 months, PSG was repeated. Body mass index (BMI) was measured and the Epworth Sleepiness Scale (ESS) score was determined. Using criteria for evaluating OSAHS surgical treatment efficacy, an AHI below 5 times/h
Eur Arch Otorhinolaryngol (2015) 272:407–412
was considered cured thus successful; an AHI that decreased more than 50 % and B20 times/h was considered markedly effective, thus successful; and patients who did not meet the standard for markedly effective were considered to have failed treatment. Statistical analysis was performed using software SPSS13.0. The ESS score and PSG monitoring indicators postoperatively were compared to those measured after follow-up for more than 12 months. P \ 0.05 was considered to be statistically significant.
Results General clinical information of the patients Twenty-three patients were included in the study (21 males and 2 females). All patients experienced nocturnal snoring, breath-holding spells, apnea, daytime sleepiness, fatigue, morning headaches, poor memory and other clinical manifestations, and were followed up for 12–48 months after UPPP was performed. Therein, 7 patients were performed UPPP in our hospital and 16 in other hospitals. None of the cases showed significant postoperative symptom improvements after a short remission. OSAHS was diagnosed by PSG again, and AHI was greater than or equal to 20 times/ h. Hence, previous UPPP was considered to be unsuccessful. The average age was 37.71 years (range 23–54). The mean BMI was 27.98 kg/m2 (range 22.3–31.2). The mean ESS score was 13.61 (range 0–24). Among the 7 patients who had undergone the previous surgery in our hospital, five were diagnosed with multi-plane obstruction before the operation. However, these patients chose not to receive the corresponding multi-plane surgery, and only UPPP surgery was performed. For the 16 patients who had received the previous surgery in other hospitals, the location of airway obstruction during the first surgery was unknown. Assessment on the site of upper airway obstruction Upper respiratory tract examinations revealed that among the 23 patients, there were one case of severe deviated nasal septum accompanied with turbinate hypertrophy and one case of adenoid hypertrophy, suggesting obstruction of the nasal cavity or nasopharynx. Furthermore, there were 18 cases of oropharyngeal obstruction and 14 cases of glossopharyngeal obstruction. Specifically, the distribution of the sites of obstruction was as follows: 7 cases of obstruction in the oropharyngeal area alone, 5 cases of obstruction in the glossopharyngeal area alone, 2 cases of obstruction in the nasal, nasopharyngeal and oropharyngeal area simultaneously and 9 cases of obstruction in the oropharyngeal and glossopharyngeal areas simultaneously.
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Clinical routine physical examinations, endoscopy and CT scan results showed that the causes of the 14 cases of glossopharyngeal obstruction were as follows: 6 cases of tongue hypertrophy, 3 cases of lingual tonsil hypertrophy and 5 cases of glossocoma. The reasons of failed UPPP Comprehensive analysis was conducted based on the data of the sites of upper airway obstruction before and after failed UPPP. The causes of the first failed UPPP for patients included in this study were mainly as follows: (1) seven patients with multi-plane obstruction did not receive effective multi-plane treatment (5 patients with oropharyngeal and glossopharyngeal obstruction and 2 patients with nasal or nasopharyngeal and oropharyngeal obstruction); (2) UPPP alone did not solve the problem of oropharyngeal obstruction very well in 18 patients (9 patients with oropharyngeal obstruction alone and 9 patients with oropharyngeal and glossopharyngeal obstruction simultaneously); (3) the site of obstruction changed after the first surgery, 2 patients showed oropharyngeal obstruction before first UPPP and showed glossopharyngeal obstruction after first UPPP. Operation, treatment outcome and complications The corresponding surgical methods of treating the OSAHS patients based on the site of obstruction were as follows: 7 cases of improved UPPP alone, 5 cases of glossopharyngeal surgery alone (2 cases of midline partial glossectomy, 1 case of lingual tonsillectomy and 2 cases of Repose surgery), 1 case of improved UPPP plus nasal expansion, 1 case of improved UPPP plus adenoidectomy, and 9 cases of improved UPPP plus glossopharyngeal surgery (4 cases of midline partial glossectomy, 2 cases of tonsillectomy and 3 cases of Repose surgery). All patients were followed up for 12–48 months, with an average follow-up time of 18 months. After following up for 12 months, PSG was re-performed, and BMI and ESS were determined. The numbers of cured, markedly improved and failed cases were counted, and the success rate of the surgery was calculated. Comparisons of BMI, ESS score and PSG result between preoperation and postoperation for all patients are shown in Table 1. Compared to the preoperation, BMI did not change significantly after the surgery, and AHI and ESS scores declined significantly (P \ 0.05) while LaSO2 increased significantly (P \ 0.05) after the surgery. There were 4 cured cases, 12 markedly improved cases, and 7 failed cases, with a success rate of 69.6 %. All 23 patients recovered and were discharged. No postoperative suffocations or deaths occurred. We also did
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410 Table 1 Changes in monitoring indicators of 23 OSHAS patients before and after the surgery
Eur Arch Otorhinolaryngol (2015) 272:407–412
BMI
AHI
LaSO2
Before surgery
28.38 ± 3.65
14.13 ± 4.67
48.50 ± 23.96
0.62 ± 0.18
After surgery
28.09 ± 3.30
5.78 ± 3.98
19.23 ± 18.13
0.77 ± 0.12
T value
0.293
6.524
4.673
3.284
P value
0.771
\0.001
\0.001
0.002
not experience any primary or secondary postoperative bleeding, infection of the surgical area, tongue hematoma or other complications. Six patients (2 cases of improved UPPP alone, 1 case of improved UPPP plus Repose, 3 cases of UPPP plus midline partial glossectomy) experienced postoperative transient nasopharyngeal reflux, and the symptom disappeared after 2–4 weeks. In the UPPP plus Repose group, two patients complained of postoperative problems about tongue movement, foreign body sensation when swallowing, vague speech and other symptoms, which all disappeared within 3 months.
Discussion The key to the occurrence of OSAHS is upper airway collapse or obstruction during sleep. Collapse or obstruction of the nasal, nasopharyngeal, oropharyngeal and glossopharyngeal areas can all be the cause. It has been demonstrated that the oropharyngeal area is the most common site of obstruction in OSAHS [7, 8]. As the basic surgery for treating OSAHS, UPPP has been widely applied. However, early reports have shown that the overall success rate of UPPP was only around 50 % [3]. Recently, with the progress of studies on OSAHS, especially the understanding of multi-plane obstruction in the upper respiratory tract and relationship between Friedman tongue position and UPPP efficacy [4], the efficacy of UPPP has been improved substantially and using UPPP to treat OSAHS has been relatively clearly determined [5, 9]. Nonetheless, the efficacy of UPPP in the treatment for OSAHS is still not completely satisfactory, and there are still some patients who face the treatment failure. The causes of the first failed UPPP for patients included in this study were mainly as follows: 1. Patients with multi-plane obstruction did not receive effective multi-plane treatment. Among the 7 patients who had undergone the first UPPP in our hospital, 5 patients diagnosed with multi-plane obstruction (oropharyngeal and glossopharyngeal obstruction simultaneously) before the first UPPP refused to undergo glossopharyngeal surgery due to fear of risks, unwillingness to have neck incision, tracheotomy or high cost, and only consented for UPPP, subsequently resulting in treatment failure. In addition, for
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ESS
the patients who received the first UPPP in other hospitals, although the preoperative airway assessment was not clear, in two cases there was obvious nasal obstruction or adenoid hypertrophy, demonstrating that the existing multi-plane obstruction had not been effectively treated. Farmer et al. [15] reported that when OSAHS patients with failed UPPP surgery received glossopharyngeal surgical treatment, satisfactory outcomes were achieved. For patients in whom preoperative assessment confirmed the presence of nasal, nasopharyngeal or glossopharyngeal obstruction, the corresponding surgical treatment could also lead to satisfactory results. These data demonstrate that multi-plane obstruction that is not properly treated is one of the reasons for UPPP failure in the treatment for OSAHS. 2. UPPP itself did not solve the problem of oropharyngeal obstruction very well. Among the 23 patients included in this study, after NPT insertion, 18 patients showed decreases in AHI by over 50 %. Of these, 9 patients had AHI less than 15 times/h, suggesting obstruction mainly in the oropharyngeal area and above, and 9 patients had AHI C 15 times/h, suggesting the existence of the oropharyngeal and glossopharyngeal multi-plane obstruction. These results demonstrated that the first UPPP did not satisfactorily solve the problem of oropharyngeal obstruction. The reason might be because the first UPPP was not adequate. Notable indications included overly long retained soft palate and/or uvula, contracture of the scar at the cut edge of the sort palate toward the posterior pharyngeal wall, and obvious oropharyngeal stenosis revealed by endoscopy or CT scan. The second improved UPPP further expanded the oropharyngeal airway by resecting the excessive soft palate and/or uvula, and the follow-up results demonstrated the effectiveness of the improved UPPP in treating oropharyngeal stenosis. 3. The stenotic plane changed after the first surgery. Among all patients, two received detailed assessment before the first UPPP in our hospital. After oropharyngeal obstruction was determined, improved UPPP was performed. Early on after the first UPPP, the symptoms were relieved by and large. However, 6 months later snoring and breath-holding spells recurred and gradually worsened. Therefore, the patients were re-admitted to our hospital, one at 14 months and the other at 17 months after the first UPPP. Preoperative assessment then revealed that the
Eur Arch Otorhinolaryngol (2015) 272:407–412
obstruction was mainly located in the glossopharyngeal area, and after glossopharyngeal surgery the symptoms were relieved. The reason behind this phenomenon might be that after the first UPPP, glossocoma occurred due to loss of tonsils and part of pharyngeal muscles on both sides of the pharynx, and the retroglossal space became the new stenotic plane. 4. Pharyngeal wall collapse and increased pharyngeal wall compliance are difficult to treat surgically. In our clinical practice, we saw four patients with failed UPPP (not included in this study), in whom oropharyngeal obstruction was confirmed by NPT-PSG. However, endoscopy and CT scan showed adequate space, normal morphology and sufficient cross-sectional area for ventilation in the oropharyngeal airway. Considering that performing another UPPP was difficult to further expand the oropharyngeal airway and that the treatment was very likely to fail, these 4 patients did not undergo reoperation. For these 4 patients, when Mu¨ller’s maneuver was observed with endoscope, it was found that the oropharyngeal side-walls collapsed toward the midline, leading to oropharyngeal airway closure. The reason for treatment failure using UPPP in these patients might be increased pharyngeal wall collapse. The study reported by Soares et al. [16], that some of the patients with failed UPPP had got lower pharyngeal wall and supraglottic tissue collapse, was consistent with our speculation. To ensure the success of the reoperation, it is necessary to re-evaluate the upper respiratory tract of patients with failed UPPP to determine the site and cause of airway obstruction and to perform the corresponding targeted surgery for good outcome. Due to the presence of bone or cartilage in the nasal and nasopharyngeal area, endoscopy and CT scan for morphological evaluation of this area are sufficient for preliminary confirmation or exclusion of nasal and nasopharyngeal obstruction [12]. In contrast, the oropharyngeal and glossopharyngeal area does not contain bone or cartilage, and endoscopy, CT and other morphological evaluation methods alone cannot accurately determine the site of obstruction [17]. For patients with failed UPPP, it is particularly important to accurately locate the site of obstruction using examination during overnight natural sleep. In addition to an upper respiratory tract continuous pressure monitoring system or AG200 diagnosis system [18, 19], it has been suggested that NPT-PSG is a simple and effective means of diagnosing oropharyngeal and glossopharyngeal obstruction [9–11]. In the present study, the presence of oropharyngeal or glossopharyngeal obstruction was determined via NPT-PSG. If AHI revealed by NPT-PSG was reduced by over 50 % and was less than 15 times/h, it was considered to be predominantly oropharyngeal obstruction. If AHI revealed by NPT-PSG was reduced by less than 50 % and was greater than 15 times/h,
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it was considered to be predominantly glossopharyngeal obstruction, and if AHI was reduced by over 50 % and was greater than 15 times/h, it was considered to be oropharyngeal and glossopharyngeal obstruction simultaneously. Clinical routine examination, endoscopy and CT scan results were mainly used for analyzing the cause of the corresponding upper respiratory tract obstruction. Airway assessment in this study revealed that although all 23 patients included in this study had received UPPP treatment, the oropharyngeal area was still the most common site of airway obstruction (18/23), followed by glossopharyngeal obstruction (14/23). In addition, oropharyngeal obstruction alone (7/23) and glossopharyngeal obstruction alone (5/23) were relatively few. Multiplane obstruction was relatively common, including oropharyngeal plus glossopharyngeal obstruction (9/23) and nasal, nasopharyngeal plus oropharyngeal obstruction (2/ 23). These results suggested that because the main reason for the failure of UPPP surgery might be that multi-plane obstruction was not effectively treated, the possibility of retained oropharyngeal obstruction could not be ruled out. To achieve satisfactory outcome before the second surgical treatment, it was necessary to perform complete re-evaluation of the upper respiratory tract of patients with failed UPPP to determine the site of obstruction and to carry out the corresponding surgery. After the site of airway obstruction has been determined, corresponding surgical treatment should be designed targeting the cause of the obstruction in the area. In our study, there were 2 cases of nasal and nasopharyngeal obstruction, and nasal expansion or adenoidectomy was performed. The 18 patients with oropharyngeal obstruction underwent improved UPPP treatment. For the 14 patients with glossopharyngeal obstruction, the surgeries were relatively complex and diverse. Based on our knowledge and experience, glossopharyngeal surgical operation mainly included three types: (1) for glossopharyngeal airway stenosis caused by obvious tongue hypertrophy, midline partial glossectomy should be performed [13]; (2) for glossopharyngeal airway stenosis caused by lingual tonsil hypertrophy, lingual tonsillectomy should be performed; (3) for patients in whom there was no obvious morphological anomaly of the glossopharyngeal airway and the obstruction might be caused by glossocoma, Repose tongue-base suspension should be performed [14]. The follow-up results of our study showed that the AHI of the patients was significantly decreased and LaSO2 was significantly increased after the second UPPP, and the success rate was 69.6 %. This suggested that re-evaluation of the upper respiratory tract of patients with failed UPPP and performance of the required surgical treatment might still have good results. In summary, the reasons for failed UPPP for treatment of OSAHS are relatively complex and diverse, and among
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the failed cases there are still a relatively large number of patients with oropharyngeal obstruction. Detailed preoperative assessment of the patient’s airway condition to decide the site of the airway obstruction, followed by corresponding surgical treatment, can still result in satisfactory treatment outcomes. Conflict of interest
None.
References 1. Isono S, Remmers JE (1994) Anatomy and physiology of upper airway obstruction. In: Kryger HH (ed) Principles and practice of sleep medicine, 2nd edn. Saunders, Philadelphia, pp 642–656 2. Braga A, Carboni LH, do Lago T, Kepper DS, Eckeli A, Valera FC (2013) Is uvulopalatopharyngoplasty still an option for the treatment of obstructive sleep apnea? Eur Arch Otorhinolaryngol 27(2):549–554 3. Fujita S (1984) UPPP for sleep apnea and snoring. Ear Nose Throat J 63:224–235 4. Friedman M, Ibrahim H, Joseph NJ (2004) Staging of obstructive sleep apnea/hypopnea syndrome: a guide to appropriate treatment. Laryngoscope 114(3):454–459 5. Han D, Ye J, Lin Z, Wang J, Wang J, Zhang Y (2005) Revised uvulopalatopharyngoplasty with uvula preservation and its clinical study. ORL J Otorhinolaryngol Relat Spec 67(4):213–219 6. Iber C, Ancoli-Israel S, Chesson AL, Quan SF (2007) The AASM manual for the scoring of sleep and associated events: rules, terminology and technical specifications. American Academy of Sleep Medicine, Westchester 7. Li S, Dong X, Shi H, Dong W, Qu S, Chen D, Wang G, Bao J (2002) Localization of upper airway stricture in patients with obstructive sleep apnea syndrome by CT scan. Chin J Otorhinolaryngol. 37(2):133–136 8. Soares D, Folbe AJ, Yoo G, Badr MS, Rowley JA, Lin HS (2012) Drug-induced sleep endoscopy vs. awake Muller’s maneuver in
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the diagnosis of severe upper airway obstruction. Otolaryngol Head Neck Surg 148:151–156 Li S, Wu D, Bao J, Shi H (2014) The nasopharyngeal tube: a simple and effective tool to indicate the need for uvulopalatopharyngoplasty. Laryngoscope 124(4):1023–1028 Li SH, Wu DH, Bao JM, Shi HJ (2013) Outcomes of upper airway reconstructive surgery for obstructive sleep apnea syndrome based on polysomnography after nasopharyngeal tube insertion. Chin Med J 126(24):4674–4678 Li S, Wu D, Bao J, Qin J (2014) Nasopharyngeal tube: a simple and effective tool to screen patients indicated for glossopharyngeal surgery. J Clin Sleep Med 10(4):385–389 Han D, Zhang L (2011) Nasal cavity ventilation expansion techniques. Acta Otolaryngol 131(12):1244–1248 Li S, Shi H (2013) Lingual artery CTA-guided midline partial glossectomy for treatment of obstructive sleep apnea hypopnea syndrome. Acta Otolaryngol 133(7):749–754 Li S, Wu D, Shi H (2013) Treatment of obstructive sleep apnea hypopnea syndrome caused by glossoptosis with tongue-base suspension. Eur Arch Otorhinolaryngol 270(11):2915–2920 Farmer WC, Giudici SC (2000) Site of airway collapse in obstructive sleep apnea after uvulopalatopharyngoplasty. Ann Otol Rhinol Laryngol 109(6):581–584 Soares D, Sinawe H, Folbe AJ, Yoo G, Badr S, Rowley JA, Lin HS (2012) Lateral oropharyngeal wall and supraglottic airway collapse associated with failure in sleep apnea surgery. Laryngoscope 122(2):473–479 Li S, Hei R, Wu D, Shi H (2014) Localization of glossopharyngeal obstruction using nasopharyngeal tube versus Friedman tongue position classification in obstructive sleep apnea hypopnea syndrome. Eur Arch Otorhinolaryngol 271(8):2241–2245 Singh A, Al-Reefy H, Hewitt R, Kotecha B (2008) Evaluation of ApneaGraph in the diagnosis of sleep-related breathing disorders. Eur Arch Otorhinolaryngol 265(12):1489–1494 Demin H, Jingying Y, Jun W, Qingwen Y, Yuhua L, Jiangyong W (2002) Determining the site of airway obstruction in obstructive sleep apnea with airway pressure measurements during sleep. Laryngoscope 112(11):2081–2085
LARYNGOLOGY
Reoperation on patients with obstructive sleep apnea–hypopnea syndrome after failed uvulopalatopharyngoplasty Shuhua Li • Dahai Wu • Hongjin Shi
Received: 18 June 2014 / Accepted: 16 October 2014 / Published online: 21 October 2014 Ó Springer-Verlag Berlin Heidelberg 2014
Abstract The goals of this study were to explore the reasons after failed uvulopalatopharyngoplasty (UPPP) in some patients with obstructive sleep apnea–hypopnea syndrome (OSAHS), and to observe the efficacy of the second surgery. Twenty-three OSAHS patients with failed UPPP were included in the study. Routine physical exams, electronic endoscopy, computed tomography scan and polysomnography after nasopharyngeal tube insertion were performed to assess the site of upper airway obstruction, and corresponding appropriate surgical treatment was carried out based on the diagnosis. Comprehensive evaluation of the 23 patients revealed that the sites of obstruction after failed UPPP were as follows: 7 cases predominantly in the oropharyngeal area, 2 cases in the nasal, nasopharyngeal and oropharyngeal area, 5 cases predominantly in the glossopharyngeal area and 9 cases in the oropharyngeal and glossopharyngeal areas. Correspondingly, 7 cases underwent improved UPPP alone, 2 cases underwent adenoidectomy or nasal expansion and improved UPPP, 5 cases underwent glossopharyngeal surgery alone and 9 cases underwent improved UPPP and glossopharyngeal surgery. Follow-up for more than 12 months showed that there were four cured cases, 12 cases with marked improvement, and 7 cases with treatment failure. The success rate was 69.6 %. After undergoing UPPP, OSAHS patients may still have oropharyngeal airway obstruction.
S. Li (&) D. Wu H. Shi Department of Otolaryngology-head and Neck Surgery, General Hospital of Shenyang Military Area Command, No.83, Wenhua Road, Shenhe District, Shenyang 110840, China e-mail: [email protected]
By performing a detailed preoperative assessment on the patient’s airway condition and clarifying the site of obstruction, performing the second surgical treatment can still achieve a relatively satisfactory treatment outcome. Keywords Obstructive sleep apnea–hypopnea syndrome Uvulopalatopharyngoplasty Failure Nasopharyngeal tube Reoperation
Introduction Obstructive sleep apnea hypopnea syndrome (OSAHS) refers to apnea and hypoventilation caused by upper airway collapse during sleep, accompanied by snoring, disrupted sleep structure, frequent occurrence of oxygen desaturation, daytime sleepiness and other symptoms [1]. The key to the occurrence of OSAHS is upper airway collapse or obstruction during sleep. In addition to continuous positive airway pressure (CPAP) therapy, surgery is also an effective method for treating OSAHS. As a basic surgery for the treatment of OSAHS, uvulopalatopharyngoplasty (UPPP) has been widely applied [2]. However, despite many improvements are made since the beginning of the application of UPPP for treating OSAHS, UPPP alone may still fail in some cases [3–5]. Subsequent treatment for patients after failed UPPP is necessary. If CPAP treatment cannot be tolerated or accepted by the patient, another surgical treatment has to be performed. In recent years, our group conducted assessment on the upper airway condition and site of obstruction for OSAHS patients in whom UPPP had failed, and re-performed surgical treatment based on the assessment results. The goals of this study were to explore the reasons after failed UPPP in some patients with OSAHS, and to observe the efficacy of the second surgery.
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408
Materials and methods
Eur Arch Otorhinolaryngol (2015) 272:407–412
Assessment on the site of upper airway obstruction and surgical treatment
Patient selection This study was approved by the ethics committee of the Medical Research Institute. All the patients were recruited from among the patients treated at the Department of Otorhinolaryngology Head and Neck Surgery from January 2010 to December 2012. Patient selection criteria were as follows: (1) having performed UPPP for treatment of OSAHS; (2) following up for more than 12 months after UPPP; (3) meeting a standard to reoperation based on a cut-off point of 20 times/h for apnea–hypopnea index (AHI); (4) no micrognathia and other abnormalities in craniofacial structure; (5) being unable or unwilling to accept CPAP treatment; (6) having a strong need for surgical treatment; and (7) having signed informed consent. Polysomnography (PSG) monitoring and upper respiratory tract examination The polywin PSG system (Respironics Inc., US) was used for sleep monitoring in all patients. PSG examinations were in accordance with American Sleep Association standards [6]. AHI and lowest oxygen saturation (LaSO2) during sleep were used as the main diagnostic indicators. Patients who were considered to require reoperation based on a cutoff point of 20 times/h for AHI were included, and LaSO2 was as a reference index. To assess the site of upper airway obstruction, all patients experienced a routine physical examination and other auxiliary examinations, including Friedman tongue position classification (FTP), upper respiratory tract computed tomography (CT) imaging, conventional electronic endoscopic examination, endoscopic observation of Muller action and PSG examination after nasopharyngeal tube insertion (NPT-PSG). FTP, CT scan and endoscopic examination were conducted with conventional methods [4, 7, 8]. NPT-PSG procedures were described shortly as follows [9–11]. The silicone nasopharyngeal tube (NPT) was selected based on nasal cavity anatomy. A tube with a 7-mm internal diameter (ID) was used in 10 patients, and 8-mm ID tubes were used in 13 patients. After one percent of ephedrine and dicaine were applied to shrink and anesthetize nasal cavity tissues, liquid paraffin was used to lubricate the surface of the NPT, which was gently inserted into the wider anterior nostril until the distal end of the tube was just beyond the free edge of the soft palate. The tube was secured to the anterior nostril with a drawstring to prevent it from moving during sleep. PSG was repeated after successful insertion of the NPT. The examination procedure and diagnostic indices were the same as in the first PSG.
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For assessment, the upper respiratory tract was divided into the following three parts: the nasal cavity-nasopharynx, oropharynx and glossopharynx. Evaluation of the nasal cavity-nasopharynx was primarily based on nasal endoscopy and CT scan results. Those with an obvious deviated nasal septum, turbinate hypertrophy, new growth in the nasal cavity or adenoid hypertrophy were considered to have nasal cavity-nasopharyngeal obstruction and appropriate surgical treatments were performed [12]. Evaluations of the oropharyngeal and glossopharyngeal areas were mainly based on NPT-PSG results. If NPT-PSG examination showed a 50 % reduction or greater in level of AHI compared to PSG result before NPT insertion and the AHI after NPT insertion was less than 15 times/h, it was assumed that there was no obvious obstruction in the glossopharyngeal area, and the obstruction was primarily located in the oropharyngeal area. In this case, improved UPPP [9, 10] was performed. Improved UPPP mainly involved further expansion of the pharyngeal cavity via removal of the part of the soft palate, uvula re-shaping and other means. If NPT-PSG revealed that AHI was greater than or equal to 15 times/h, the case was considered as obvious glossopharyngeal obstruction [9–11]. In particular, if the AHI determined by NPT-PSG was reduced less than 50 % compared to the first PSG, the obstruction was considered to be predominantly in the glossopharyngeal area and glossopharyngeal surgery was performed. If the AHI was reduced more than 50 %, it was assumed that obstructions were present in both oropharyngeal and glossopharyngeal areas, and improved UPPP along with glossopharyngeal surgery was performed. For patients with confirmed glossopharyngeal obstruction, Friedman tongue position, endoscopy and CT scan results were combined to determine the cause of the glossopharyngeal obstruction, and the appropriate surgical procedure was carried out accordingly. Patients with lingual tonsillar hypertrophy underwent lingual tonsillectomy and those with tongue hypertrophy underwent midline partial glossectomy [13]. Patients without obvious tongue hypertrophy or lingual tonsillar hyperplasia underwent tongue-base suspension (Repose surgery) [14]. Follow-up, efficacy evaluation and statistical analysis All patients underwent follow-up for more than 12 months, with an average follow-up time of 18 months. After 12 months, PSG was repeated. Body mass index (BMI) was measured and the Epworth Sleepiness Scale (ESS) score was determined. Using criteria for evaluating OSAHS surgical treatment efficacy, an AHI below 5 times/h
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was considered cured thus successful; an AHI that decreased more than 50 % and B20 times/h was considered markedly effective, thus successful; and patients who did not meet the standard for markedly effective were considered to have failed treatment. Statistical analysis was performed using software SPSS13.0. The ESS score and PSG monitoring indicators postoperatively were compared to those measured after follow-up for more than 12 months. P \ 0.05 was considered to be statistically significant.
Results General clinical information of the patients Twenty-three patients were included in the study (21 males and 2 females). All patients experienced nocturnal snoring, breath-holding spells, apnea, daytime sleepiness, fatigue, morning headaches, poor memory and other clinical manifestations, and were followed up for 12–48 months after UPPP was performed. Therein, 7 patients were performed UPPP in our hospital and 16 in other hospitals. None of the cases showed significant postoperative symptom improvements after a short remission. OSAHS was diagnosed by PSG again, and AHI was greater than or equal to 20 times/ h. Hence, previous UPPP was considered to be unsuccessful. The average age was 37.71 years (range 23–54). The mean BMI was 27.98 kg/m2 (range 22.3–31.2). The mean ESS score was 13.61 (range 0–24). Among the 7 patients who had undergone the previous surgery in our hospital, five were diagnosed with multi-plane obstruction before the operation. However, these patients chose not to receive the corresponding multi-plane surgery, and only UPPP surgery was performed. For the 16 patients who had received the previous surgery in other hospitals, the location of airway obstruction during the first surgery was unknown. Assessment on the site of upper airway obstruction Upper respiratory tract examinations revealed that among the 23 patients, there were one case of severe deviated nasal septum accompanied with turbinate hypertrophy and one case of adenoid hypertrophy, suggesting obstruction of the nasal cavity or nasopharynx. Furthermore, there were 18 cases of oropharyngeal obstruction and 14 cases of glossopharyngeal obstruction. Specifically, the distribution of the sites of obstruction was as follows: 7 cases of obstruction in the oropharyngeal area alone, 5 cases of obstruction in the glossopharyngeal area alone, 2 cases of obstruction in the nasal, nasopharyngeal and oropharyngeal area simultaneously and 9 cases of obstruction in the oropharyngeal and glossopharyngeal areas simultaneously.
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Clinical routine physical examinations, endoscopy and CT scan results showed that the causes of the 14 cases of glossopharyngeal obstruction were as follows: 6 cases of tongue hypertrophy, 3 cases of lingual tonsil hypertrophy and 5 cases of glossocoma. The reasons of failed UPPP Comprehensive analysis was conducted based on the data of the sites of upper airway obstruction before and after failed UPPP. The causes of the first failed UPPP for patients included in this study were mainly as follows: (1) seven patients with multi-plane obstruction did not receive effective multi-plane treatment (5 patients with oropharyngeal and glossopharyngeal obstruction and 2 patients with nasal or nasopharyngeal and oropharyngeal obstruction); (2) UPPP alone did not solve the problem of oropharyngeal obstruction very well in 18 patients (9 patients with oropharyngeal obstruction alone and 9 patients with oropharyngeal and glossopharyngeal obstruction simultaneously); (3) the site of obstruction changed after the first surgery, 2 patients showed oropharyngeal obstruction before first UPPP and showed glossopharyngeal obstruction after first UPPP. Operation, treatment outcome and complications The corresponding surgical methods of treating the OSAHS patients based on the site of obstruction were as follows: 7 cases of improved UPPP alone, 5 cases of glossopharyngeal surgery alone (2 cases of midline partial glossectomy, 1 case of lingual tonsillectomy and 2 cases of Repose surgery), 1 case of improved UPPP plus nasal expansion, 1 case of improved UPPP plus adenoidectomy, and 9 cases of improved UPPP plus glossopharyngeal surgery (4 cases of midline partial glossectomy, 2 cases of tonsillectomy and 3 cases of Repose surgery). All patients were followed up for 12–48 months, with an average follow-up time of 18 months. After following up for 12 months, PSG was re-performed, and BMI and ESS were determined. The numbers of cured, markedly improved and failed cases were counted, and the success rate of the surgery was calculated. Comparisons of BMI, ESS score and PSG result between preoperation and postoperation for all patients are shown in Table 1. Compared to the preoperation, BMI did not change significantly after the surgery, and AHI and ESS scores declined significantly (P \ 0.05) while LaSO2 increased significantly (P \ 0.05) after the surgery. There were 4 cured cases, 12 markedly improved cases, and 7 failed cases, with a success rate of 69.6 %. All 23 patients recovered and were discharged. No postoperative suffocations or deaths occurred. We also did
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410 Table 1 Changes in monitoring indicators of 23 OSHAS patients before and after the surgery
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BMI
AHI
LaSO2
Before surgery
28.38 ± 3.65
14.13 ± 4.67
48.50 ± 23.96
0.62 ± 0.18
After surgery
28.09 ± 3.30
5.78 ± 3.98
19.23 ± 18.13
0.77 ± 0.12
T value
0.293
6.524
4.673
3.284
P value
0.771
\0.001
\0.001
0.002
not experience any primary or secondary postoperative bleeding, infection of the surgical area, tongue hematoma or other complications. Six patients (2 cases of improved UPPP alone, 1 case of improved UPPP plus Repose, 3 cases of UPPP plus midline partial glossectomy) experienced postoperative transient nasopharyngeal reflux, and the symptom disappeared after 2–4 weeks. In the UPPP plus Repose group, two patients complained of postoperative problems about tongue movement, foreign body sensation when swallowing, vague speech and other symptoms, which all disappeared within 3 months.
Discussion The key to the occurrence of OSAHS is upper airway collapse or obstruction during sleep. Collapse or obstruction of the nasal, nasopharyngeal, oropharyngeal and glossopharyngeal areas can all be the cause. It has been demonstrated that the oropharyngeal area is the most common site of obstruction in OSAHS [7, 8]. As the basic surgery for treating OSAHS, UPPP has been widely applied. However, early reports have shown that the overall success rate of UPPP was only around 50 % [3]. Recently, with the progress of studies on OSAHS, especially the understanding of multi-plane obstruction in the upper respiratory tract and relationship between Friedman tongue position and UPPP efficacy [4], the efficacy of UPPP has been improved substantially and using UPPP to treat OSAHS has been relatively clearly determined [5, 9]. Nonetheless, the efficacy of UPPP in the treatment for OSAHS is still not completely satisfactory, and there are still some patients who face the treatment failure. The causes of the first failed UPPP for patients included in this study were mainly as follows: 1. Patients with multi-plane obstruction did not receive effective multi-plane treatment. Among the 7 patients who had undergone the first UPPP in our hospital, 5 patients diagnosed with multi-plane obstruction (oropharyngeal and glossopharyngeal obstruction simultaneously) before the first UPPP refused to undergo glossopharyngeal surgery due to fear of risks, unwillingness to have neck incision, tracheotomy or high cost, and only consented for UPPP, subsequently resulting in treatment failure. In addition, for
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ESS
the patients who received the first UPPP in other hospitals, although the preoperative airway assessment was not clear, in two cases there was obvious nasal obstruction or adenoid hypertrophy, demonstrating that the existing multi-plane obstruction had not been effectively treated. Farmer et al. [15] reported that when OSAHS patients with failed UPPP surgery received glossopharyngeal surgical treatment, satisfactory outcomes were achieved. For patients in whom preoperative assessment confirmed the presence of nasal, nasopharyngeal or glossopharyngeal obstruction, the corresponding surgical treatment could also lead to satisfactory results. These data demonstrate that multi-plane obstruction that is not properly treated is one of the reasons for UPPP failure in the treatment for OSAHS. 2. UPPP itself did not solve the problem of oropharyngeal obstruction very well. Among the 23 patients included in this study, after NPT insertion, 18 patients showed decreases in AHI by over 50 %. Of these, 9 patients had AHI less than 15 times/h, suggesting obstruction mainly in the oropharyngeal area and above, and 9 patients had AHI C 15 times/h, suggesting the existence of the oropharyngeal and glossopharyngeal multi-plane obstruction. These results demonstrated that the first UPPP did not satisfactorily solve the problem of oropharyngeal obstruction. The reason might be because the first UPPP was not adequate. Notable indications included overly long retained soft palate and/or uvula, contracture of the scar at the cut edge of the sort palate toward the posterior pharyngeal wall, and obvious oropharyngeal stenosis revealed by endoscopy or CT scan. The second improved UPPP further expanded the oropharyngeal airway by resecting the excessive soft palate and/or uvula, and the follow-up results demonstrated the effectiveness of the improved UPPP in treating oropharyngeal stenosis. 3. The stenotic plane changed after the first surgery. Among all patients, two received detailed assessment before the first UPPP in our hospital. After oropharyngeal obstruction was determined, improved UPPP was performed. Early on after the first UPPP, the symptoms were relieved by and large. However, 6 months later snoring and breath-holding spells recurred and gradually worsened. Therefore, the patients were re-admitted to our hospital, one at 14 months and the other at 17 months after the first UPPP. Preoperative assessment then revealed that the
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obstruction was mainly located in the glossopharyngeal area, and after glossopharyngeal surgery the symptoms were relieved. The reason behind this phenomenon might be that after the first UPPP, glossocoma occurred due to loss of tonsils and part of pharyngeal muscles on both sides of the pharynx, and the retroglossal space became the new stenotic plane. 4. Pharyngeal wall collapse and increased pharyngeal wall compliance are difficult to treat surgically. In our clinical practice, we saw four patients with failed UPPP (not included in this study), in whom oropharyngeal obstruction was confirmed by NPT-PSG. However, endoscopy and CT scan showed adequate space, normal morphology and sufficient cross-sectional area for ventilation in the oropharyngeal airway. Considering that performing another UPPP was difficult to further expand the oropharyngeal airway and that the treatment was very likely to fail, these 4 patients did not undergo reoperation. For these 4 patients, when Mu¨ller’s maneuver was observed with endoscope, it was found that the oropharyngeal side-walls collapsed toward the midline, leading to oropharyngeal airway closure. The reason for treatment failure using UPPP in these patients might be increased pharyngeal wall collapse. The study reported by Soares et al. [16], that some of the patients with failed UPPP had got lower pharyngeal wall and supraglottic tissue collapse, was consistent with our speculation. To ensure the success of the reoperation, it is necessary to re-evaluate the upper respiratory tract of patients with failed UPPP to determine the site and cause of airway obstruction and to perform the corresponding targeted surgery for good outcome. Due to the presence of bone or cartilage in the nasal and nasopharyngeal area, endoscopy and CT scan for morphological evaluation of this area are sufficient for preliminary confirmation or exclusion of nasal and nasopharyngeal obstruction [12]. In contrast, the oropharyngeal and glossopharyngeal area does not contain bone or cartilage, and endoscopy, CT and other morphological evaluation methods alone cannot accurately determine the site of obstruction [17]. For patients with failed UPPP, it is particularly important to accurately locate the site of obstruction using examination during overnight natural sleep. In addition to an upper respiratory tract continuous pressure monitoring system or AG200 diagnosis system [18, 19], it has been suggested that NPT-PSG is a simple and effective means of diagnosing oropharyngeal and glossopharyngeal obstruction [9–11]. In the present study, the presence of oropharyngeal or glossopharyngeal obstruction was determined via NPT-PSG. If AHI revealed by NPT-PSG was reduced by over 50 % and was less than 15 times/h, it was considered to be predominantly oropharyngeal obstruction. If AHI revealed by NPT-PSG was reduced by less than 50 % and was greater than 15 times/h,
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it was considered to be predominantly glossopharyngeal obstruction, and if AHI was reduced by over 50 % and was greater than 15 times/h, it was considered to be oropharyngeal and glossopharyngeal obstruction simultaneously. Clinical routine examination, endoscopy and CT scan results were mainly used for analyzing the cause of the corresponding upper respiratory tract obstruction. Airway assessment in this study revealed that although all 23 patients included in this study had received UPPP treatment, the oropharyngeal area was still the most common site of airway obstruction (18/23), followed by glossopharyngeal obstruction (14/23). In addition, oropharyngeal obstruction alone (7/23) and glossopharyngeal obstruction alone (5/23) were relatively few. Multiplane obstruction was relatively common, including oropharyngeal plus glossopharyngeal obstruction (9/23) and nasal, nasopharyngeal plus oropharyngeal obstruction (2/ 23). These results suggested that because the main reason for the failure of UPPP surgery might be that multi-plane obstruction was not effectively treated, the possibility of retained oropharyngeal obstruction could not be ruled out. To achieve satisfactory outcome before the second surgical treatment, it was necessary to perform complete re-evaluation of the upper respiratory tract of patients with failed UPPP to determine the site of obstruction and to carry out the corresponding surgery. After the site of airway obstruction has been determined, corresponding surgical treatment should be designed targeting the cause of the obstruction in the area. In our study, there were 2 cases of nasal and nasopharyngeal obstruction, and nasal expansion or adenoidectomy was performed. The 18 patients with oropharyngeal obstruction underwent improved UPPP treatment. For the 14 patients with glossopharyngeal obstruction, the surgeries were relatively complex and diverse. Based on our knowledge and experience, glossopharyngeal surgical operation mainly included three types: (1) for glossopharyngeal airway stenosis caused by obvious tongue hypertrophy, midline partial glossectomy should be performed [13]; (2) for glossopharyngeal airway stenosis caused by lingual tonsil hypertrophy, lingual tonsillectomy should be performed; (3) for patients in whom there was no obvious morphological anomaly of the glossopharyngeal airway and the obstruction might be caused by glossocoma, Repose tongue-base suspension should be performed [14]. The follow-up results of our study showed that the AHI of the patients was significantly decreased and LaSO2 was significantly increased after the second UPPP, and the success rate was 69.6 %. This suggested that re-evaluation of the upper respiratory tract of patients with failed UPPP and performance of the required surgical treatment might still have good results. In summary, the reasons for failed UPPP for treatment of OSAHS are relatively complex and diverse, and among
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the failed cases there are still a relatively large number of patients with oropharyngeal obstruction. Detailed preoperative assessment of the patient’s airway condition to decide the site of the airway obstruction, followed by corresponding surgical treatment, can still result in satisfactory treatment outcomes. Conflict of interest
None.
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