Treatment-emergent central sleep apnoea after surgery for obstructive sleep apnoea

Nasopharyngeal tube effects on alleviating sleep hypoxemia during the first night following velopharyngeal surgery in patients with obstructive sleep apnea syndrome

STUDY OBJECTIVES

To investigate the feasibility and effectiveness of nasopharyngeal tube (NPT) insertion in alleviating sleep hypoxemia during the first night after velopharyngeal surgery in patients with obstructive sleep apnea syndrome (OSAS).

METHODS

In this prospective nonblinded, randomized, controlled study, 46 patients with obstructive sleep apnea syndrome (OSAS) who underwent velopharyngeal surgery were enrolled and randomly allocated to the control group (with no NPT insertion) and the NPT insertion group. Both groups underwent overnight pulse oximetry tests during the first postoperative night.

RESULTS

One patient in the NPT insertion group was excluded because of involuntary self-removal of NPT during sleep. A total of 45 patients with OSAS were included for analysis, with 23 in the control group and 22 in the NPT insertion group. No significant differences in preoperative baseline information were found between the two groups. Compared with the patients in the control group, those patients in the NPT insertion group showed a significantly higher value of the lowest oxygen saturation of oximetry during the first postoperative night (85.0 ± 4.0% vs 79.3 ± 8.0%) (P = .005). The percentage of patients with lowest oxygen saturation of oximetry < 80% in the NPT insertion group was only 9.1% (2 of 22), which was significantly lower than 39.1% (9 of 23) in the control group (P = .035). No patient reported unbearable discomfort related to NPT insertion. The most common mild discomfort was occasional pharyngeal foreign body sensation (6 of 22, 27.3%).

CONCLUSIONS

NPT insertion could lessen the severity of sleep hypoxemia during the first night after velopharyngeal surgery in patients with OSAS and showed excellent compliance. This method could be a potential alternative option for decreasing the risks of complications related to severe sleep hypoxemia during the early postoperative days.

CITATION

Zhang J, Guan S, Zhang C, Du X, Li T, Xiao S. Nasopharyngeal tube effects on alleviating sleep hypoxemia during the first night following velopharyngeal surgery in patients with obstructive sleep apnea syndrome. J Clin Sleep Med. 2023;19(2):303-308.

Practice recommendations for the role of physiotherapy in the management of sleep disorders: the 2022 Brazilian Sleep Association Guidelines

This clinical guideline supported by the Brazilian Sleep Association comprises a brief history of the development of Brazilian sleep physiotherapy, outlines the role of the physiotherapist as part of a sleep health team, and describes the clinical guidelines in respect of the management of some sleep disorders by the physiotherapist (including sleep breathing disorders, i.e., obstructive sleep apnea, central sleep apnea, upper airway resistance syndrome, hypoventilation syndromes and overlap syndrome, and pediatric sleep breathing disorders; sleep bruxism; circadian rhythms disturbances; insomnia; and Willis-Ekbom disease/periodic limb movement disorder. This clinical practice guideline reflects the state of the art at the time of publication and will be reviewed and updated as new information becomes available.

Central and mixed sleep apnea related to patients treated with maxillomandibular advancement for obstructive sleep apnea: A retrospective cohort study

The aim of this study was to evaluate the clinical efficacy of maxillomandibular advancement (MMA) for obstructive sleep apnea (OSA) patients with a percentage of central and mixed apnea index in the total apnea-hypopnea index (CMAI%) ≧25%. Patients treated with MMA for OSA were retrospectively evaluated for baseline and postoperative patient data and polysomnographic results. The pre- and postoperative obstructive, central and mixed apnea parameters were compared. Of the included 78 patients, 21 patients (27%) presented with CMAI% ≧25% (median CMAI%, 49.1%; 35.9-63.8) prior to MMA. In 67% of these cases, MMA resulted in CMAI% <25 (median CMAI%, 6.1%; 2.1-8.9) and significantly improved the apnea-hypopnea index (AHI) (p < 0.001), the lowest oxyhemoglobin saturation (p < 0.001), central and mixed apnea index (p < 0.001), percentage of central and mixed apneas of total AHI (p = 0.004), central apnea index (p < 0.001), and mixed apnea index (p < 0.001). CMAI% ≧25% emerged in 25% of patients after MMA (median CMAI%, 49.1%; 35.9-63.8). Within the undeniable limitations of the study, it seems that the presence of CMAI% ≧25% should not be regarded as a contraindication for MMA in OSA patients.

Persistent Treatment-Emergent Central Sleep Apnea (TECSA) Following Hypoglossal Nerve Stimulation

PURPOSE

Since 2001, hypoglossal nerve stimulators (HNS) have been used worldwide to treat patients with obstructive sleep apnea (OSA). Recently, a few studies reported treatment-emergent central sleep apnea (TECSA) with spontaneous resolution following HNS. However, the evidence of persistent development of TECSA during long-term care visits was lacking. As a result, this study first report two patients with persistent TECSA and describe their development phenotype during more than two years of follow-up visits to help explore the influencing factors and underlying mechanisms.

PATIENTS AND METHODS

This retrospective study included twenty-seven patients who underwent HNS implantation from 2016 to 2021. Their demographic data, pre- and postoperative sleep study characteristics, and device use settings were collected. The possible factors associated with post-operative elevated CSA (central apnea index ≥5) were evaluated. Moreover, the development phenotype of the TECSA was observed and followed up with a titration trial study.

RESULTS

Among overall 27 patients with OSA, 3 patients with an increased preoperative Epworth Sleepiness Score (ESS) got an elevated CSA (CAI ≥ 5). Two of these 3 patients developed a persistent TECSA with a significant negative correlation between obstructive apnea index (OAI) and central and mixed sleep apnea index (CMAI) (R = -0.745, P = 0.021). These development phenotypes might be associated with different stimulation amplitudes of the HNS device. Furthermore, the following titration trial study also suggested that different amplitudes would influence the development of TECSA following HNS.

CONCLUSION

OSA patients with severe daytime sleepiness are more likely to have elevated CSA following HNS. An inappropriate stimulation amplitude might influence the development course of TECSA in such patients.

Treatment-emergent central sleep apnea associated with non-positive airway pressure therapies in obstructive sleep apnea patients: A systematic review

This systematic review summarizes the prevalence of treatment-emergent central sleep apnea (TECSA) occurring with therapies other than positive airway pressure (PAP) for the management of obstructive sleep apnea (OSA). We describe its natural course as well as the proposed underlying pathophysiological mechanisms and the clinical management of affected patients. A systematic search of PubMed, Embase, Web of science, and the Cochrane Library was performed until June 2020. Eighteen studies (n = 284 patients) were included. TECSA was observed in 31 patients with the use of four different medical devices (mandibular advancement device, hypoglossal nerve stimulation, tongue stabilizing device and nasal expiratory PAP) and after three different types of surgical treatments (tracheostomy, maxillofacial surgery and oro-nasal surgery). Due to the paucity of data available, it was not possible to establish a clear prevalence rate of TECSA for each alternative treatment. After the initiation of non-PAP treatments, a systematic reassessment of the treatment efficacy with follow-up sleep studies will be helpful to identify TECSA. A spontaneous resolution over time was described as well as a persistence of TECSA. In this case, treatment should focus on patients' specific underlying pathophysiology. Overall, the limited current literature suggests that this phenomenon is rare (<4%).