Frances Chung

Dr. Frances Chung

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Research Focus & Metrics

Academic Career Length

46Years (1981-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 May 2008 in Anesthesiology
Verified
Journal Article
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FCFrances Chung
Frances Chung
BYBalaji Yegneswaran
Balaji Yegneswaran
PLPu Liao
Pu Liao
SCSharon A. Chung
Sharon A. Chung
SVSanthira Vairavanathan
Santhira Vairavanathan
CSColin M. Shapiro
Colin M. Shapiro
Background: Obstructive sleep apnea (OSA) is a major risk factor for perioperative adverse events. However, no screening tool for OSA has been validated in surgical patients. This study was conducted to develop and validate a concise and easy-to-use questionnaire for OSA screening in surgical patients. Methods: After hospital ethics approval, preoperative patients aged 18 yr or older and without previously diagnosed OSA were recruited. After a factor analysis, reliability check, and pilot study; four yes/no questions were used to develop this screening tool. The four questions were respectively related to snoring, tiredness during daytime, observed apnea, and high blood pressure (STOP). For validation, the score from the STOP questionnaire was evaluated versus the apnea-hypopnea index from monitored polysomnography. Results: The STOP questionnaire was given to 2,467 patients, 27.5% classified as being at high risk of OSA. Two hundred eleven patients underwent polysomnography, 34 for the pilot test and 177 for validation. In the validation group, the apnea-hypopnea index was 20 +/- 6. The sensitivities of the STOP questionnaire with apnea-hypopnea index greater than 5, greater than 15, and greater than 30 as cutoffs were 65.6, 74.3, and 79.5%, respectively. When incorporating body mass index, age, neck circumference, and gender into the STOP questionnaire, sensitivities were increased to 83.6, 92.9, and 100% with the same apnea-hypopnea index cutoffs. Conclusions: The STOP questionnaire is a concise and easy-to-use screening tool for OSA. It has been developed and validated in surgical patients at preoperative clinics. Combined with body mass index, age, neck size, and gender, it had a high sensitivity, especially for patients with moderate to severe OSA.

1 January 2014 in Anesthesia & Analgesia
Verified
Journal Article
Closed access
TGTong J. Gan
Tong J. Gan
PDPierre Diemunsch
Pierre Diemunsch
AHAshraf S. Habib
Ashraf S. Habib
AKAnthony Kovac
Anthony Kovac
PKPeter Kranke
Peter Kranke
MTMartin R. Tramèr
Martin R. Tramèr
The present guidelines are the most recent data on postoperative nausea and vomiting (PONV) and an update on the 2 previous sets of guidelines published in 2003 and 2007. These guidelines were compiled by a multidisciplinary international panel of individuals with interest and expertise in PONV under the auspices of the Society for Ambulatory Anesthesia. The panel members critically and systematically evaluated the current medical literature on PONV to provide an evidence-based reference tool for the management of adults and children who are undergoing surgery and are at increased risk for PONV. These guidelines identify patients at risk for PONV in adults and children; recommend approaches for reducing baseline risks for PONV; identify the most effective antiemetic single therapy and combination therapy regimens for PONV prophylaxis, including nonpharmacologic approaches; recommend strategies for treatment of PONV when it occurs; provide an algorithm for the management of individuals at increased risk for PONV as well as steps to ensure PONV prevention and treatment are implemented in the clinical setting.

1 March 2016 in Chest
Verified
Journal Article
Open access
FCFrances Chung
Frances Chung
HAHairil Rizal Abdullah
Hairil Rizal Abdullah
PLPu Liao
Pu Liao
Today, there exists a high prevalence of obstructive sleep apnea (OSA) in the general population, a great proportion of which remains undiagnosed. The STOP-Bang questionnaire has been specifically developed to meet the need for a reliable, concise and easy-to-use screening tool. It consists of eight dichotomous (yes/no) items related to the clinical features of sleep apnea (Snoring, Tiredness, Observed apnea, high blood Pressure, BMI, age, neck circumference and male gender). The total score ranges from 0 to 8. Patients can be classified for their OSA risk based on their respective scores. The sensitivity of STOP-Bang score ≥3 to detect moderate-to-severe OSA (AHI > 15) and severe OSA (AHI > 30) is 93% and 100% respectively. The corresponding negative predictive values are 90% and 100%. As the STOP-Bang score increases from 0-2 to 7-8, the probability of moderate-to-severe OSA increases from 18% to 60%, and the probability of severe OSA rises from 4% to 38%. Patients with a STOP-Bang score of 0 to 2 can be classified as “low risk” for moderate-to-severe OSA, while those with a score of 5 to 8 can be classified as “high risk” for moderate-to-severe OSA. In patients whose STOP-Bang scores land in the mid-range (3 or 4), further criteria are required for classification. For example, a STOP score of ≥ 2 + BMI > 35 kg/m2 would classify that patient as having a high risk for moderate-to-severe OSA. In this way, patients can be stratified for their OSA risk according to their STOP-Bang scores.

1 May 2012 in British Journal of Anaesthesia
Verified
Journal Article
Open access
FCFrances Chung
Frances Chung
RSR. Subramanyam
R. Subramanyam
PLP. Liao
P. Liao
ESE. Sasaki
E. Sasaki
CSC. Shapiro
C. Shapiro
YSY. Sun
Y. Sun
The STOP-Bang questionnaire is used to screen patients for obstructive sleep apnoea (OSA). We evaluated the association between STOP-Bang scores and the probability of OSA. After Institutional Review Board approval, patients who visited the preoperative clinics for a scheduled inpatient surgery were approached for informed consent. Patients answered STOP questionnaire and underwent either laboratory or portable polysomnography (PSG). PSG recordings were scored manually. The BMI, age, neck circumference, and gender (Bang) were documented. Over 4 yr, 6369 patients were approached and 1312 (20.6%) consented. Of them, 930 completed PSG, and 746 patients with complete data on PSG and STOP-Bang questionnaire were included for data analysis. The median age of 746 patients was 60 yr, 49% males, BMI 30 kg m(-2), and neck circumference 39 cm. OSA was present in 68.4% with 29.9% mild, 20.5% moderate, and 18.0% severe OSA. For a STOP-Bang score of 5, the odds ratio (OR) for moderate/severe and severe OSA was 4.8 and 10.4, respectively. For STOP-Bang 6, the OR for moderate/severe and severe OSA was 6.3 and 11.6, respectively. For STOP-Bang 7 and 8, the OR for moderate/severe and severe OSA was 6.9 and 14.9, respectively. The predicted probabilities for moderate/severe OSA increased from 0.36 to 0.60 as the STOP-Bang score increased from 3 to 7 and 8. In the surgical population, a STOP-Bang score of 5-8 identified patients with high probability of moderate/severe OSA. The STOP-Bang score can help the healthcare team to stratify patients for unrecognized OSA, practice perioperative precautions, or triage patients for diagnosis and treatment.

1 July 2003 in Anesthesia & Analgesia
Verified
Journal Article
Closed access
TGTong J Gan
Tong J Gan
TMTricia Meyer
Tricia Meyer
CAChristian C Apfel
Christian C Apfel
FCFrances Chung
Frances Chung
PDPeter J Davis
Peter J Davis
DCDepartment of Anesthesiology, Duke University Medical Center
Department of Anesthesiology, Duke University Medical Center
We present evidence-based guidelines developed by an international panel of experts for the management of postoperative nausea and vomiting.

14 December 2015 in PLOS ONE
Verified
Journal Article
Open access
PDF file
MNMahesh Nagappa
Mahesh Nagappa
PLPu Liao
Pu Liao
JWJean Wong
Jean Wong
DADennis Auckley
Dennis Auckley
SRSatya Krishna Ramachandran
Satya Krishna Ramachandran
FCFrances Chung
Frances Chung
Diagnosing obstructive sleep apnea (OSA) is clinically relevant because untreated OSA has been associated with increased morbidity and mortality. The STOP-Bang questionnaire is a validated screening tool for OSA. We conducted a systematic review and meta-analysis to determine the effectiveness of STOP-Bang for screening patients suspected of having OSA and to predict its accuracy in determining the severity of OSA in the different populations. A search of the literature databases was performed. Inclusion criteria were: 1) Studies that used STOP-Bang questionnaire as a screening tool for OSA in adult subjects (>18 years); 2) The accuracy of the STOP-Bang questionnaire was validated by polysomnography—the gold standard for diagnosing OSA; 3) OSA was clearly defined as apnea/hypopnea index (AHI) or respiratory disturbance index (RDI) ≥ 5; 4) Publications in the English language. The quality of the studies were explicitly described and coded according to the Cochrane Methods group on the screening and diagnostic tests. Seventeen studies including 9,206 patients met criteria for the systematic review. In the sleep clinic population, the sensitivity was 90%, 94% and 96% to detect any OSA (AHI ≥ 5), moderate-to-severe OSA (AHI ≥15), and severe OSA (AHI ≥30) respectively. The corresponding NPV was 46%, 75% and 90%. A similar trend was found in the surgical population. In the sleep clinic population, the probability of severe OSA with a STOP-Bang score of 3 was 25%. With a stepwise increase of the STOP-Bang score to 4, 5, 6 and 7/8, the probability rose proportionally to 35%, 45%, 55% and 75%, respectively. In the surgical population, the probability of severe OSA with a STOP-Bang score of 3 was 15%. With a stepwise increase of the STOP-Bang score to 4, 5, 6 and 7/8, the probability increased to 25%, 35%, 45% and 65%, respectively. This meta-analysis confirms the high performance of the STOP-Bang questionnaire in the sleep clinic and surgical population for screening of OSA. The higher the STOP-Bang score, the greater is the probability of moderate-to-severe OSA.