Biomedical subjects

Thomas S T Li

Publications and source records attributed to Thomas S T Li.

4 recordsLinked to original sources

PubMed2005

Sputum bacteriology in patients with acute exacerbations of COPD in Hong Kong.

STUDY OBJECTIVE: To study the demographics and sputum microbiology of patients admitted to a teaching hospital with acute exacerbations of chronic obstructive pulmonary disease (AECOPD). DESIGN: A retrospective study. SETTING: A tertiary university hospital in Hong Kong. PATIENTS: All episodes of AECOPD, patient demographics, length of stay, sputum culture and radiological results admitted in the first half of the year 2000 were retrieved from hospital records. RESULTS: There were 329 patients with 418 episodes of AECOPD without concomitant pneumonia. The age of the patients was 74.4+/-8.3 years. The acute hospital length of stay for an episode of AECOPD was 7.3+/-6.5 days. Haemophilus influenzae was the commonest organism found in sputum (23.1%), followed by Pseudomonas aeruginosa (6.3%) and Streptococcus pneumoniae (4.0%). Mycobacterium tuberculosis was found in 1.1% of the admissions. Presence of organisms in sputum had no association with the hospital length of stay and intensive care unit admissions. In patients whose FEV1 was >50% of predicted values, there was a higher chance of positive sputum growth of H. influenzae than those with FEV1 <50% (16/44 vs. 31/162 episodes, respectively, P=0.02). CONCLUSIONS: H. influenzae was the commonest bacterium isolated in sputum in patients with AECOPD. In areas endemic of tuberculosis, it is advisable to use fluoroquinolones for AECOPD with caution.

Acute Disease↗

PubMed2002

Severe obstructive sleep apnea is associated with left ventricular diastolic dysfunction.

INTRODUCTION: Hypertension is common in patients with obstructive sleep apnea (OSA). However, the effect of OSA on ventricular function, especially diastolic function, is not clear. Therefore, we have assessed the prevalence of diastolic dysfunction in patients with OSA and the relationship between diastolic parameters and severity of OSA. METHODS: Sixty-eight consecutive patients with OSA confirmed by polysomnography underwent echocardiography. Diastolic function of the left ventricle was determined by transmitral valve pulse-wave Doppler echocardiography. Various baseline characteristics, severity of OSA, and echocardiographic parameters were compared between patients with and without diastolic dysfunction. RESULTS: There were 61 male and 7 female patients with a mean age of 48.1 +/- 11.1 years, body mass index of 28.5 +/- 4.3 kg/m(2), and apnea/hypopnea index (AHI) of 44.3 +/- 23.2/h (mean +/- SD). An abnormal relaxation pattern (ARP) in diastole was noted in 25 patients (36.8%). Older age (52.7 +/- 8.9 years vs 45.1 +/- 11.3 years, p = 0.005), hypertension (56% vs 20%, p = 0.002), and a lower minimum pulse oximetric saturation (SpO(2)) during sleep (70.5 +/- 17.9% vs 78.8 +/- 12.9%, respectively; p = 0.049) were more common in patients with ARP. By multivariate analysis, minimum SpO(2) < 70% was an independent predictor of ARP (odds ratio, 4.34; 95% confidence interval, 1.23 to 15.25; p = 0.02) irrespective of age and hypertension. Patients with AHI > or = 40/h had significantly longer isovolumic relaxation times than those with AHI < 40/h (106 +/- 19 ms vs 93 +/- 17 ms, respectively; p = 0.005). CONCLUSION: Diastolic dysfunction with ARP was common in patients with OSA. More severe sleep apnea was associated with a higher degree of left ventricular diastolic dysfunction in this study.

Diastole↗

PubMed2002

Prevalence of sleep-disordered breathing and continuous positive airway pressure compliance: results in chinese patients with first-ever ischemic stroke.

OBJECTIVE: To assess the prevalence of sleep-disordered breathing (SDB), continuous positive airway pressure (CPAP) acceptance, and CPAP compliance in patients who have experienced ischemic stroke. DESIGN: A case-controlled study. SETTING: A university hospital. MEASUREMENTS AND RESULTS: We recruited 23 women and 28 men, who were admitted to the hospital within 4 days of stroke onset, with a mean (+/- SD) age of 64.2 +/- 13.0 years and a body mass index (BMI) of 24.3 +/- 4.4 kg/m(2) for this study. Twenty-seven patients (53%) and 9 patients (17.6%), respectively, reported a history of snoring and severe daytime sleepiness prior to experiencing a stroke, while the mean Epworth sleepiness scale score was 6.8 +/- 3.6. Polysomnography revealed 34 patients (67%) with an apnea-hypopnea index (AHI) of > or = 10 events per hour, 31 patients (61%) with an AHI of > or = 15 events per hour, and 25 patients (49%) with an AHI of > or = 20 events per hour. Significant obstructive SDB, defined as an AHI of > or = 20/h, was more prevalent in ischemic stroke patients than in control subjects (49% vs 24%, respectively; p = 0.04) and was associated with a higher BMI (p = 0.046). Among the 34 patients with an AHI of > or = 10/h, CPAP titration was tolerated by 16 patients, but only 4 patients who had typical sleep apnea features proceeded to home CPAP treatment with objective compliance over a period of 3 months of 2.5 +/- 0.6 h per night. A subgroup of 20 patients not receiving CPAP showed partial spontaneous improvement of SDB at 1 month (baseline AHI, 32.3 +/- 17.6 events per hour; AHI at 1 month, 23.0 +/- 18.8 events per hour; p = 0.01) with a trend toward improvement for the obstructive but no significant change for the central events, whereas no improvement in AHI was noted for the four patients receiving CPAP. CONCLUSION: There is a high prevalence of obstructive SDB in patients who have experienced acute ischemic stroke, which, in many cases, is different from classic obstructive sleep apnea syndrome, and this is reflected by the lack of significant sleepiness, poor CPAP acceptance, and partial spontaneous improvement at 1 month.

Aged↗

PubMed2002

Prevalence of sleep disturbances in Chinese patients with end stage renal failure on maintenance hemodialysis.

BACKGROUND: Sleep disorders, such as daytime sleepiness, insomnia, restless legs syndrome (RLS) and obstructive sleep apnea syndrome (OSAS) have been reported as prevalent among patients with end stage renal failure(ESRF). MATERIAL/METHODS: As there is little published data from Southeast Asia, a sleep questionnaire was administered to all patients (N=43, 27 males) on chronic hemodialysis (HD) at the Prince of Wales Hospital, Hong Kong, to assess their sleep complaints. RESULTS: The mean age was 49.5 +/- 11.3 years (mean I SD) with mean body mass index (BMI) of 22.6 +/- 3.6 kg/m2. Frequent awakenings and sleep onset insomnia were the most frequent complaints (79% each), while daytime sleepiness occurred in 74% of patients. Sleep maintenance insomnia and pruritus occurred in 64% and 60% of patients respectively. Symptoms of RLS were reported by 70% of patients. The prevalence of OSAS was estimated by the frequency of observed choking (4.7% of cases), witnessed apnea (14%), snoring and witnessed apnea (9.3%), disruptive snoring (14%), disruptive snoring and witnessed apnea (2.3%), extremely loud snoring (4.7%). CONCLUSIONS: Our questionnaire survey revealed a high prevalence of sleep complaints such as frequent awakenings, daytime sleepiness, insomnia and RLS in patients with ESRF on maintenance HD, but a relatively low prevalence of OSAS, which may be related to the low BMI of our ESRF patients.

Adult↗