Yewon Chung1,2,3,4, Frances L Garden2,3,4, Adelle S Jee5,6, Subash Srikantha1, Saurabh Gupta1,3, Peter R Buchanan1,2,3, Peter W Collett1,2,3, Guy B Marks1,2,3,4, Hima Vedam1,2,3,4. 1. Department of Respiratory and Sleep Medicine, Liverpool Hospital, Sydney, New South Wales, Australia. 2. Respiratory, Sleep and Environmental Health Research Group, University of New South Wales, Sydney, New South Wales, Australia. 3. South Western Sydney Clinical School, University of New South Wales, Sydney, New South Wales, Australia. 4. Ingham Institute of Applied Medical Research, Sydney, New South Wales, Australia. 5. Department of Respiratory Medicine, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia. 6. Central Clinical School, University of Sydney, Sydney, New South Wales, Australia.
Abstract
BACKGROUND: Evidence-based screening tools are required for detection of daytime hypercapnia in high-risk patient populations. AIMS: To determine the validity of supine awake oximetry as a test for daytime hypercapnia and severe sleep disordered breathing (SDB) in super-obese patients. METHODS: This was a cross-sectional diagnostic test evaluation of super-obese adults (body mass index >50 kg/m2 ) presenting to Liverpool Hospital, Australia, between 2009 and 2015 for diagnostic polysomnography (PSG) and arterial blood gas measurement. Supine awake oxygen saturation (SpO2 ) was determined using oximetry measurements from the first three awake epochs of raw PSG data. Sensitivity and specificity of SpO2 for detecting patients with daytime hypercapnia (PaCO2 >45 mmHg) and severe SDB (respiratory disturbance index (RDI) >30 events/h) were assessed at various cut-off points and displayed using a receiver operating characteristic (ROC) curve. Area under the ROC curve and positive and negative predictive values (PPV and NPV) in the present patient population were derived. RESULTS: Of 52 patients, 23 (44%) had daytime hypercapnia. SpO2 measured awake in the supine position was associated with the presence of daytime hypercapnia but not with the presence of severe SDB. Overall, awake supine SpO2 <91.2% had 34.8% sensitivity, 96.6% specificity and 88.8% PPV, and SpO2 <96.7% had 87.0% sensitivity, 20.7% specificity and 66.7% NPV for the presence of daytime hypercapnia. CONCLUSION: Awake supine oximetry is an easily performed test that may have novel use in identifying patients at high risk of respiratory failure. Future studies are required to evaluate prospectively its role in screening patients at risk of daytime hypercapnia.
BACKGROUND: Evidence-based screening tools are required for detection of daytime hypercapnia in high-risk patient populations. AIMS: To determine the validity of supine awake oximetry as a test for daytime hypercapnia and severe sleep disordered breathing (SDB) in super-obesepatients. METHODS: This was a cross-sectional diagnostic test evaluation of super-obese adults (body mass index >50 kg/m2 ) presenting to Liverpool Hospital, Australia, between 2009 and 2015 for diagnostic polysomnography (PSG) and arterial blood gas measurement. Supine awake oxygen saturation (SpO2 ) was determined using oximetry measurements from the first three awake epochs of raw PSG data. Sensitivity and specificity of SpO2 for detecting patients with daytime hypercapnia (PaCO2 >45 mmHg) and severe SDB (respiratory disturbance index (RDI) >30 events/h) were assessed at various cut-off points and displayed using a receiver operating characteristic (ROC) curve. Area under the ROC curve and positive and negative predictive values (PPV and NPV) in the present patient population were derived. RESULTS: Of 52 patients, 23 (44%) had daytime hypercapnia. SpO2 measured awake in the supine position was associated with the presence of daytime hypercapnia but not with the presence of severe SDB. Overall, awake supine SpO2 <91.2% had 34.8% sensitivity, 96.6% specificity and 88.8% PPV, and SpO2 <96.7% had 87.0% sensitivity, 20.7% specificity and 66.7% NPV for the presence of daytime hypercapnia. CONCLUSION: Awake supine oximetry is an easily performed test that may have novel use in identifying patients at high risk of respiratory failure. Future studies are required to evaluate prospectively its role in screening patients at risk of daytime hypercapnia.
Authors: Michael V Braganza; Patrick J Hanly; Kristin L Fraser; Willis H Tsai; Sachin R Pendharkar Journal: J Clin Sleep Med Date: 2020-09-15 Impact factor: 4.062
Authors: Babak Mokhlesi; Juan Fernando Masa; Jan L Brozek; Indira Gurubhagavatula; Patrick B Murphy; Amanda J Piper; Aiman Tulaimat; Majid Afshar; Jay S Balachandran; Raed A Dweik; Ronald R Grunstein; Nicholas Hart; Roop Kaw; Geraldo Lorenzi-Filho; Sushmita Pamidi; Bhakti K Patel; Susheel P Patil; Jean Louis Pépin; Israa Soghier; Maximiliano Tamae Kakazu; Mihaela Teodorescu Journal: Am J Respir Crit Care Med Date: 2019-08-01 Impact factor: 21.405