Patients presenting for colonoscopy: A great opportunity to screen for sleep apnea

Predictive value of NoSAS questionnaire combined with the modified Mallampati grade for hypoxemia during routine sedation for gastrointestinal endoscopy

BACKGROUND

The incidence of hypoxemia during painless gastrointestinal endoscopy remains a matter of concem. To date, there is no recognized simple method to predict hypoxemia in digestive endoscopic anesthesia. The NoSAS (neck circumference, obesity, snoring, age, sex) questionnaire, an objective and simple assessment scale used to assess obstructive sleep apnea (OSA), combined with the modified Mallampati grade (MMP), may have certain screening value. This combination may allow anesthesiologists to anticipate, manage, and consequently decrease the occurrence of hypoxemia.

METHODS

This study was a prospective observational trial. The primary endpoint was the incidence of hypoxaemia defined as pulse oxygen saturation (SpO2) < 95% for 10 s. A total of 2207 patients admitted to our hospital for painless gastrointestinal endoscopy were studied. All patients were measured for age, height, weight, body mass index, neck circumference, snoring, MMP, and other parameters. Patients were divided into hypoxemic and non-hypoxemic groups based on the SpO2. The ROC curve was plotted to evaluate the screening value of the NoSAS questionnaire separately and combined with MMP for hypoxemia. The total NoSAS score was evaluated at cut-off points of 8 and 9.

RESULTS

With a NoSAS score ≥ 8 as the critical value for analysis, the sensitivity for hypoxemia was 58.3%, the specificity was 88.4%, and the area under the ROC was 0.734 (P < 0.001, 95% CI: 0.708-0.759). With a NoSAS score ≥ 9 as a critical value, the sensitivity for hypoxemia was 36.50%, the specificity rose to 96.16%, and the area under the ROC was 0.663 (P < 0.001, 95% CI: 0.639-0.688). With the NoSAS Score combined with MMP for analysis, the sensitivity was 78.4%, the specificity was 84%, and the area under the ROC was 0.859 (P < 0.001, 95%CI:0.834-0.883).

CONCLUSIONS

As a new screening tool, the NoSAS questionnaire is simple, convenient, and useful for screening hypoxemia. This questionnaire, when paired withMMP, is likely to be helpful for the screening of hypoxemia.

[Clinical characteristics and risk factors of lower extremity arterial disease in patients with diabetic foot ulcer]

OBJECTIVE

To investigate the clinical characteristics of lower extremity arterial disease (LEAD) and its risk factors in patients with diabetic foot ulcer (DFU).

METHODS

We retrospectively collected the clinical and follow-up data of 650 patients with DFU treated in the Department of Endocrinology and Metabolism of Nanfang Hospital between January, 2017 and December, 2019. We compared the data between patients who had LEAD and those without LEAD and used a multivariate logistic regression model to analyze the risk factors of LEAD in DFU patients.

RESULTS

Among the 650 DFU patients, 470 (72.4%) had LEAD. The patients were followed up for a mean of 3.5 months, and the mean healing time of DFU was 2.55 months; healing of DFU occurred in 453 patients and 183 patients received amputation. The patients with LEAD and those without LEAD differed significantly in age, hospitalization costs, diastolic blood pressure (DBP), glycated hemoglobin, blood lipid levels, disease course, ankle brachial index, healing time, smoking history, clinical outcomes, Wagner grade and imaging results (P < 0.05). Multivariate logistic regression analysis identified age (OR=1.070, 95% CI: 1.049-1.091), smoking history (OR= 2.013, 95% CI: 1.268-3.195), and a decreased DBP (OR=0.980, 95% CI: 0.963-0.997) as independent risk factors for LEAD in DFU patients. A prolonged healing time was a prominent clinical feature of DFU complicated by LEAD.

CONCLUSION

DFU patients have a high incidence of LEAD, which leads to high rates of disability and mortality and is associated with an advanced age, high smoking rate and longer healing time. A decreased DBP is also a risk factor for LEAD in DFU patients.

Oxygen desaturation during flexible bronchoscopy with propofol sedation is associated with sleep apnea: the PROSA-Study

BACKGROUND

Obstructive sleep apnea (OSA) is characterized by repetitive episodes of complete or partial obstruction of the upper airways during sleep. Conscious sedation for flexible bronchoscopy (FB) places patients in a sleep-like condition. We hypothesize that oxygen desaturation during flexible bronchoscopy may help to detect undiagnosed sleep apnea.

METHODS

Single-centre, investigator-initiated and driven study including consecutive patients undergoing FB for clinical indication. Patients completed the Epworth Sleepiness Scale (ESS), Lausanne NoSAS score, STOP-BANG questionnaire and the Berlin questionnaire and underwent polygraphy within 7 days of FB. FB was performed under conscious sedation with propofol. Oxygen desaturation during bronchoscopy was measured with continuous monitoring of peripheral oxygen saturation with ixTrend (ixellence GmbH, Germany).

RESULTS

145 patients were included in the study, 62% were male, and the average age was 65.8 ± 1.1 years. The vast majority of patients (n = 131, 90%) proved to fulfill OSA criteria based on polygraphy results: 52/131 patients (40%) had mild sleep apnea, 49/131 patients (37%) moderate sleep apnea and 30/131 patients (23%) severe sleep apnea. Patients with no oxygen desaturation had a significantly lower apnea-hypopnea index than patients with oxygen desaturation during bronchoscopy (AHI 11.94/h vs 21.02/h, p = 0.011). This association remained significant when adjusting for the duration of bronchoscopy and propofol dose (p = 0.023; 95% CI 1.382; 18.243) but did not hold when also adjusting for age and BMI.

CONCLUSION

The severity of sleep apnea was associated to oxygen desaturation during flexible bronchoscopy under conscious sedation. Patients with oxygen desaturation during bronchoscopy might be considered for sleep apnea screening.

TRIAL REGISTRATION

The Study was approved by the Ethics Committee northwest/central Switzerland, EKNZ (EK 16/13) and was carried out according to the Declaration of Helsinki and Good Clinical Practice guidelines. Due to its observational character, the study did not require registration at a clinical trial registry.

Clinical features of snoring patients during sedative endoscopy

BACKGROUND/AIMS

Snoring is the sound of turbulence and vibration of the upper respiratory tissues and has been identified as a risk factor of obstructive sleep apnea (OSA) and cardiovascular disease. The aim of this study was to identify associated clinical factors in snoring patients undergoing sedative endoscopy.

METHODS

A total of 49 patients who snored during standard sedative endoscopy and 127 controls were prospectively enrolled from June 2015 to June 2016. The Korean version of the Berlin Questionnaire was used to identify risk factors of OSA. Clinical information, including comorbidities, was collected from electronic medical records.

RESULTS

The snoring group showed a higher risk of OSA (42.9% vs. 26.8%, p = 0.039), and a higher prevalence of coronary artery disease (10.2% vs. 0.8%, p = 0.007) and advanced gastric cancer (12.2% vs. 2.4%, p = 0.015) compared with the control group. Multivariate analysis showed that coronary artery disease (odds ratio [OR], 13.93; 95% confidence interval [CI], 1.24 to 155.90; p = 0.033) and advanced gastric cancer (OR, 5.21; 95% CI, 1.01 to 26.98; p = 0.049) were significantly associated with snoring. However, a history of gastrectomy showed only a marginally significant association with snoring (OR, 2.16; 95% CI, 0.91 to 5.11; p = 0.079).

CONCLUSION

Patients who snore during sedative endoscopy may need to be evaluated for possible coronary artery disease.