Effect of upper-airway stimulation for obstructive sleep apnoea on airway dimensions

Upper-airway stimulation (UAS) using a unilateral implantable neurostimulator for the hypoglossal nerve is an effective therapy for obstructive sleep apnoea patients with continuous positive airway pressure intolerance. This study evaluated stimulation effects on retropalatal and retrolingual dimensions during drug-induced sedation compared with wakefulness to assess mechanistic relationships in response to UAS. Patients with an implanted stimulator underwent nasal video endoscopy while awake and/or during drug-induced sedation in the supine position. The cross-sectional area, anterior-posterior and lateral dimensions of the retropalatal and retrolingual regions were measured during baseline and stimulation. 15 patients underwent endoscopy while awake and 12 underwent drug-induced sedation endoscopy. Increased levels of stimulation were associated with increased area of both the retropalatal and retrolingual regions. During wakefulness, a therapeutic level of stimulation increased the retropalatal area by 56.4% (p=0.002) and retrolingual area by 184.1% (p=0.006). During stimulation, the retropalatal area enlarged in the anterior-posterior dimension while retrolingual area enlarged in both anterior-posterior and lateral dimensions. During drug-induced sedation endoscopy, the same stimulation increased the retropalatal area by 180.0% (p=0.002) and retrolingual area by 130.1% (p=0.008). Therapy responders had larger retropalatal enlargement with stimulation than nonresponders. UAS increases both the retropalatal and retrolingual areas. This multilevel enlargement may explain reductions of the apnoea-hypopnoea index in selected patients receiving this therapy.

Upper Airway Stimulation in OSA Patients Resolves Multilevel Airway Collapse in a Dose-Response Manner

Objectives:

Upper airway stimulation (UAS) is a potential therapy for continuous positive airway pressure (CPAP)–refractory obstructive sleep apnea by hypoglossal stimulation using an implantable, programmable neurostimulator. We tested the hypothesis whether changes in stimulation amplitude would modulate palatal and tongue-base airway size during wakefulness and sedation.

Methods:

Fifteen patients underwent digital video laryngoscopy while awake and/or drug-induced sleep (DISE) at least 3 months after UAS system implantation for CPAP-refractory obstructive sleep apnea (Inspire Medical Systems, Minneapolis, MN). Neurostimulation was applied at four increasing amplitudes: first sensation, tongue movement, titrated therapeutic, and sub-discomfort. Palatal and tongue-base cross-sectional area were measured and compared between periods with and without stimulation.

Results:

Twelve patients (all male, age: 51.2±9.0 years; AHI: 28.8±7.8/h) underwent DISE; fifteen patients (all male, age: 50.4±10.2 years; AHI: 29.3±7.5/h) underwent awake laryngoscopy and eleven patients and both. During both awake and DISE, higher stimulation amplitudes had a graded response in enlarging multi-level airway dimensions, with a larger percent increase of airway size during DISE. While awake, palatal area increased between 5.0±24.0% at the lowest stimulation to 73.0±79.3% at the titrated amplitude ( P = 0.01), and tongue-base increased between 64.2±70.3% to 128.6±103.8% ( P = 0.05). During DISE, palatal area increased from 9.3±30.4% to 215.4±305.2% ( P = 0.09) and tongue-base from 12.0±45.4% to 177.3±166.4% ( P = 0.01).

Conclusions:

Upper airway stimulation increases airway size during awake surgery and improves airway collapse during sedation. Increasing stimulation amplitudes enlarges both retro-palatal and retroglossal airway size. Increased multi-level airway size is a potential therapy mechanism of upper airway stimulation when treating CPAP-refractory OSA.

Long-term self-reported treatment effects and experience of radiofrequency-induced thermotherapy of the inferior turbinates performed under local anesthesia: a retrospective analysis

Nasal obstruction due to inferior turbinate hypertrophy is a common complaint. Radiofrequency-induced thermotherapy of the inferior turbinates (RFITT) under local anesthesia is now a widely used treatment, however reports of assessment of the long-term self-reported benefits and patient satisfaction of the treatment are scarce. This study focuses on the self-reported long-term effects of treatment and experience of RFITT. A questionnaire was sent to 441 patients who underwent RFITT in our clinic to treat symptoms of impaired nasal passage due to enlarged inferior turbinates. All patients had enlarged inferior turbinates on nasal examination. Patients were included if RFITT was done under local anaesthesia, was performed more than a year before the questionnaire was forwarded and on the indication-significant nasal obstruction because of enlarged inferior turbinates. Improvement of nasal breathing (by means of a Visual Analog Scale, VAS), changes in use of nasal spray (VAS), usage of pain medication, patient friendliness of the treatment, complaints reported after treatment, permanent effect of treatment during day and night time and willingness to recommend treatment to others were analyzed. No significant post-operative complications were observed. There was a significant reduction in use of nasal spray and the majority of patients interviewed reported long-term positive effects of RFITT during the daytime. This study shows that RFITT performed under local anesthesia is a valuable, minimally invasive, patient-friendly and well-tolerated treatment in patients with impaired nasal passage due to inferior turbinate hypertrophy.

Surgery for obstructive sleep apnea: sleep endoscopy determinants of outcome

OBJECTIVES/HYPOTHESIS

Although drug-induced sleep endoscopy is often employed to determine the site of obstruction in patients with obstructive sleep apnea (OSA) who will undergo upper airway surgery, it remains unknown whether its findings are associated with surgical outcome. This study tested the hypothesis that drug-induced sleep endoscopy variables can predict the outcome of upper airway surgery in OSA patients.

STUDY DESIGN

Case series retrospective analysis.

METHODS

Forty-nine OSA patients (41 male; mean apnea-hypopnea index [AHI] 30.9 ± 18.5 events/hour) underwent propofol-induced sleep endoscopy followed by upper airway surgery (palatal surgery, and/or radiofrequency ablation of the tongue base, and/or hyoid suspension) and subsequently a follow-up polysomnography to assess surgical outcome.

RESULTS

Twenty-three patients (47%) were responders, and twenty-nine were nonresponders (53%). Nonresponders had a higher occurrence of complete or partial circumferential collapse at velum and complete antero-posterior collapse at tongue base or epiglottis in comparison with responders. Multivariate logistic regression analysis revealed that among baseline clinical and polysomnographic characteristics (e.g., AHI, body mass index) and sleep endoscopy findings, the presence of complete circumferential collapse at velum, and of complete antero-posterior collapse at tongue base were the only independent predictors of upper airway surgery failure.

CONCLUSIONS

Drug-induced sleep endoscopy can be used to predict higher likelihood of response to upper airway surgery in OSA.

Outcome of surgical treatment for fistula in ano in Crohn's disease

BACKGROUND

Recurrence rates and long-term functional outcome after surgical treatment of anal fistula in Crohn's disease were assessed.

METHODS

A consecutive series of patients was treated for Crohn's fistula in ano; those without proctitis or active sepsis underwent surgery. Sex, seton usage, infliximab, previous fistula surgery, history of segmental resection and smoking were examined as risk factors for recurrence. Continence was assessed by Vaizey scale and a colorectal Functional outcome questionnaire. Results were compared with institutional data for cryptoglandular fistulas.

RESULTS

Sixty-one patients were included, with a median follow-up of 79 (range 13-140) months. Twenty-four patients were treated with a seton, 28 by fistulotomy and nine by mucosal advancement. For low fistulas, fistulotomy was used more frequently than the seton, whereas seton drainage was used for most higher fistulas. Recurrence occurred in five of 28 and five of nine patients after fistulotomy and advancement respectively. Soiling was reported by half of the patients treated by seton versus two-thirds and three-quarters of those treated by fistulotomy and advancement respectively. Functional outcomes were worse for all patient groups than for cryptoglandular fistulas. No risk factor was significant.

CONCLUSION

Surgical outcome for high or complex Crohn's fistula in ano remains disappointing, and recurrence is unpredictable.

Staple line failure using the Proximate 100 mm linear cutter

PURPOSE

An incomplete linear staple line that was discovered during the stapling of an ileal pouch alerted us to evaluate potential usage concerns with linear cutters. This study was designed to assess the integrity of the staple line of three different sizes of linear staplers.

METHODS

In an animal model three different lengths of linear cutters (Proximate, Ethicon Endo-Surgery) were used to cross-staple and transect the large bowel of one pig to check for the integrity of the proximal end of the staple line.

RESULTS

Cross-stapling and transecting across the pig's large bowel demonstrated that if the tissue is advanced up to the highest number on the scale of the 100 mm stapling device, insufficient overlap between the proximal end of the staple line and the proximal end of the cut line occur.

CONCLUSIONS

Although a more than 100 mm staple line is delivered, the 100 mm cutter may not produce a double-staggered row of staples at the most proximal end of the staple line if the tissue is advanced past the 9.5 cm mark. Ethicon Endo-Surgery has agreed to add indicator markers to the scale label on the instrument to provide the user with additional guidance for tissue placement.