Validity of a simple sleep monitor for diagnosing OSA in bariatric surgery patients.

BACKGROUND: One third of bariatric surgery patients have an apnea-hypopnea index (AHI)>15/hr, representing moderate and severe forms of obstructive sleep apnea (OSA). Treating these forms of OSA is recommended to reduce the risk of perioperative complications. The AHI derived from poly(somno)graphy [P(S)G] is the gold standard for OSA diagnosis. However, performing P(S)G in all patients scheduled for bariatric surgery is time consuming and expensive. An accurate and simple screening tool able to rule out moderate to severe OSA would reduce the number of patients needing mandatory P(S)Gs. OBJECTIVES: To assess the validity of a simple sleep monitor (Checkme Health Monitor) as a screening tool for OSA in bariatric surgery patients. SETTING: Obesity Center Amsterdam, OLVG-West, Amsterdam, the Netherlands METHODS: Patients scheduled for bariatric surgery were prospectively enrolled in this study. All patients underwent preoperative P(S)G and simultaneously used the Checkme to assess the oxygen desaturation index. The diagnostic performance of the Checkme for AHI ≥15/hr was assessed using receiver operating characteristic curve analysis. RESULTS: A total of 50 patients were analyzed. Sensitivity and negative predictive value were 100% and 100%, respectively, specificity and positive predictive value were 69% and 64%, respectively, for the optimal cutoff value of Checkme-3% oxygen desaturation index ≥9/hr for P(S)G-AHI ≥15. The area under the curve value expressed by the receiver operating characteristic curve was .95. CONCLUSION: The Checkme is valid for exclusion of moderate and severe OSA in bariatric surgery patients. The Checkme enables bariatric clinics not to perform P(S)G in all patients scheduled for bariatric surgery.

Evaluation of position dependency in non-apneic snorers.

The aims of this study are to determine the prevalence of position dependency in non-apneic snorers, as defined by the American Academy of Sleep Medicine (AASM) guidelines, and to investigate the influence of various factors such as BMI, neck circumference, age, gender, and sleep efficiency on sleeping position. A cohort of consecutive patients was screened for complaints of excessive snoring or symptoms suspicious for sleep disordered breathing. Overnight polysomnographic data were collected and non-apneic snorers who met all the inclusion criteria were selected for statistical analysis. To assess position-dependent snoring, the snore index (total snores/h) was used. Supine-dependent patients were defined as having a supine snore index higher than their total non-supine snore index. 76 patients were eligible for statistical analysis. Prevalence of position dependency in non-apneic snorers was 65.8% (p < 0.008). A stepwise regression showed that only BMI had a significant effect (p < 0.003) on the supine snore index. This is the first study that uses the AASM guidelines to accurately define non-apneic snorers (AHI < 5) and provides scientific evidence that the majority of non-apneic snorers are supine dependent. Furthermore, these results show that non-apneic snorers with a higher BMI snore more frequently in supine position. The use of sleep position therapy therefore, has the potential to play a significant role in improving snoring and its associated physical and psychosocial health outcomes in this population.

Assessment of the effect of bariatric surgery on obstructive sleep apnea at two postoperative intervals.

BACKGROUND: Studies have reported significant improvement of obstructive sleep apnea (OSA) in obese patients after bariatric surgery (BS). Weight loss following BS is rapid in the first few months, but it can take at least 1 year to reach the final result. The aim of this study is to measure the effect of BS on various clinical, respiratory, and sleep parameters of OSA at two postoperative intervals. METHODS: Prospectively, all patients being evaluated for BS underwent a polysomnography (PSG). Patients diagnosed with OSA preoperatively were invited to undergo a PSG at least 6 months postoperatively and if OSA persisted, again at least 12 months postoperatively. RESULTS: One hundred ten patients underwent a first postoperative PSG 7.7 months after surgery. The mean apnea-hypopnea index (AHI) significantly decreased from 39.5 to 15.6/h. In 58.2 %, the AHI was reduced to below 10 and in 25.5 % to below 5. Fifty patients underwent a first PSG 7.1 months and a second PSG 16.9 months after surgery. The mean AHI decreased from 49.1 to 22.7 to 17.4/h following BS. CONCLUSIONS: BS initiates dramatic improvement and even remission of clinical and sleep parameters during the first 7 months, which continues at a slower rate over the next 10 months. We recommend a follow-up PSG after surgery to check for residual disease and if necessary retritration of continuous positive airway pressure, which may lead to higher treatment compliance.

Obstructive sleep apnea is underrecognized and underdiagnosed in patients undergoing bariatric surgery.

The aim of this study was to evaluate prevalence of obstructive sleep apnea among patients undergoing bariatric surgery and the predictive value of various clinical parameters: body mass index (BMI), neck circumference (NC) and the Epworth Sleepiness Scale (ESS). We performed a prospective, multidisciplinary, single-center observational study including all patients on the waiting list for bariatric surgery between June 2009 and June 2010, irrespective of history or clinical findings. Patients visited our ENT outpatient clinic for patient history, ENT and general examination and underwent a full night polysomnography, unless performed previously. As much as 69.9% of the patients fulfilled the criteria for OSA (mean BMI 44.2 ± SD 6.4 kg/m(2)); 40.4% of the patients met the criteria for severe OSA. The regression models found BMI to be the best clinical predictor, while the ROC curve found the NC to be the most accurate predictor of the presence of OSA. The discrepancy of the results and the poor statistical power suggest that all three clinical parameters are inadequate predictors of OSA. In conclusion, in this large patient series, 69.9% of patients undergoing BS meet the criteria for OSA. More than 40% of these patients have severe OSA. A mere 13.3% of the patients were diagnosed with OSA before being placed on the waiting list for BS. On statistical analysis, increased neck circumference, BMI and the ESS were found to be insufficient predictors of the presence of OSA. Polysomnography is an essential component of the preoperative workup of patients undergoing BS. When OSA is found, specific perioperative measures are indicated.

Influence of antiplatelet therapy on cerebral micro-emboli after carotid endarterectomy using postoperative transcranial Doppler monitoring.

AIM: To study the effect of different antiplatelet regimens (APT) on the rate of postoperative TCD registered micro-embolic signals (MES) following carotid endarterectomy (CEA). DESIGN: Prospective, randomised, double-blinded, pilot study. METHODS: The study group of 102 CEA patients (76 men, mean age 66.8 years) was randomised to routine Asasantin (Dipyridamole 200mg/Aspirin 25mg) twice daily (group I; n=39), Asasantin plus 75 mg Clopidogrel once daily (group II; n=33), or Asasantin plus Rheomacrodex (Dextran 40) 100g/L iv; 500 ml (group III; n=30). TCD monitoring of the ipsilateral middle cerebral artery for the occurrence of MES was performed intra-operatively and during the second postoperative hour following CEA. Primary endpoints were the rate of postoperative emboli and the occurrence of cerebrovascular complications. Secondary endpoint was any adverse bleeding. RESULTS: There were no deaths or major strokes. We observed 2 intraoperative TIA's (group II and III) and 1 postoperative minor stroke (group I). In comparison with placebo, Clopidogrel or Rheomacrodex in addition to Asasantin produced no significant reduction in the number of postoperative MES. There was no significant difference between the number of postoperative MES and different antiplatelet regimens. The incidence of bleeding complications was not significantly different between the 3 APT groups. CONCLUSION: In the present study, we could not show a significant influence of different antiplatelet regimens on TCD detected postoperative embolization following CEA.

[Serious haemorrhage after conventional (adeno)tonsillectomy: rare and most often on the day of the procedure]. / Ernstige nabloeding na klassieke (adeno)tonsillectomie: zeldzaam en meestal op de dag van de ingreep.

OBJECTIVE: To analyse the incidence and timing of postoperative haemorrhage that requires re-operation following tonsillectomy or adenotonsillectomy, and to formulate a recommendation regarding the optimal duration of postoperative clinical observation. DESIGN: Retrospective. METHOD: Data were collected on the incidence of haemorrhage that required exploratory surgery in all patients who underwent adenotomy (n=3508) or tonsillectomy or adenotonsillectomy (n=4909) in the period 1996-2002 at the Sint Lucas Andreas Hospital in Amsterdam, the Netherlands. The Sluder technique was used on an outpatient basis in 2439 of the 4909 patients who underwent tonsillectomy or adenotonsillectomy; these patients were aged <10 years. The remaining 2470 patients were aged > or =10 years and underwent conventional dissection followed by 24 hours of clinical observation before being discharged. RESULTS: Postoperative haemorrhage was recorded in 0 of the 3508 patients who underwent adenotomy, 12 (0.5%) of the 2439 patients aged <10 years who underwent tonsillectomy using the Sluder technique and 43 (1.7%) of the 2470 patient aged > or =10 years who underwent conventional dissection. Of the 43 cases of haemorrhage after conventional dissection, 31 (75%) occurred within 24 hours, including 2 cases that occurred between 12 and 24 hours (2/2470; 0.08%; 95% CI: 0.001-0.29). CONCLUSION: Reducing the postoperative observation period from 24 hours to 12 hours would have unfavourable consequences in 1 (95% CI: 0-3) per 1ooo patients operated. In regard to the risk of postoperative haemorrhage, outpatient tonsillectomy and adenotonsillectomy appear to be justified for patients aged 10 years or over, provided that surgery is performed in the morning and the patient is observed in a ward that is open until the evening.