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Objectives: To study the effectiveness of noninvasive positive pressure ventilation (NIPPV) in the treatment of acute respiratory failure (ARF) in severe acute respiratory syndrome (SARS), and the associated infection risk. Methods: All patients with the diagnosis of probable SARS admitted to a regional hospital in Hong Kong from March 9 to April 28, 2003, and who had SARS-related respiratory distress complications were recruited for NIPPV usage. The health status of all health-care workers working in the NIPPV wards was closely monitored, and consent was obtained to check serum for coronavirus serology. Patient outcomes and the risk of SARS transmission to health-care workers were assessed. Results: NIPPV was applied to 20 patients (11 male patients) with ARF secondary to SARS. Mean age was 51.4 years, and mean acute physiology and chronic health evaluation II score was 5.35. Coronavirus serology was positive in 95% (19 of 20 patients). NIPPV was started 9.6 days (mean) from symptom onset, and mean duration of NIPPV usage was 84.3 h. Endotracheal intubation was avoided in 14 patients (70%), in whom the length of ICU stay was shorter (3.1 days vs 21.3 days, p < 0.001) and the chest radiography score within 24 h of NIPPV was lower (15.1 vs 22.5, p = 0.005) compared to intubated patients. Intubation avoidance was predicted by a marked reduction in respiratory rate (9.2 breaths/min) and supplemental oxygen requirement (3.1 L/min) within 24 h of NIPPV. Complications were few and reversible. There were no infections among the 105 health-care workers caring for the patients receiving NIPPV. Conclusions: NIPPV was effective in the treatment of ARF in the patients with SARS studied, and its use was safe for health-care workers.

Background Club cell protein-16 (CC16) expression has been associated with smoking-related lung function decline. The study hypothesis was that CC16 expression in both serum and bronchial epithelium is associated with lung function decline in smokers, and exposure to cigarette smoke will lead to reduction in CC16 expression in bronchial epithelial cells. Methods In a cohort of community-based male Chinese subjects recruited for lung function test in 2000, we reassessed their lung function ten years later and measured serum levels of CC16. CC16 expression was further assayed in bronchial epithelium from endobronchial biopsies taken from an independent cohort of subjects undergoing autofluorescence bronchoscopy, and tested for correlation between CC16 immunostaining intensity and lung function. In an in-vitro model, bronchial epithelial cells were exposed to cigarette smoke extract (CSE), and the expression levels of CC16 were measured in bronchial epithelial cells before and after exposure to CSE. Results There was a significant association between FEV1 decline and serum CC16 levels in smokers. Expression of CC16 in bronchial epithelium showed significant correlation with FEV1/FVC. Bronchial epithelial cells showed significant decrease in CC16 expression after exposure to CSE, followed by a subsequent rise in CC16 expression upon removal of CSE. Conclusions Results of these clinical and laboratory investigations suggested that low serum CC16 was associated with smoking-related decline in lung function, demonstrated the first time in a Chinese cohort. The data also lend support to the putative role of CC16 in protection against smoking-related bronchial epithelial damage. (Abstract word count: 243) US clinical trial registry NCT01185652, first posted 20 August, 2010.

Purpose To estimate the prevalence of undiagnosed airflow obstruction (AFO) in Hong Kong smokers with no previous diagnosis of respiratory disease, and to assess its variability when applying different prediction equations and diagnostic criteria. Methods A multicenter, population-based, cross-sectional prevalence study was performed in smokers aged 20 to 80 years. Three different criteria (fixed 70% [Global Initiative for Chronic Obstructive Lung Disease and British Thoracic Society], fixed 75%, and European Respiratory Society [ERS]) were applied to define a lower limit of normal (LLN) of the FEV 1 /FVC ratio to compare with the Hong Kong Chinese reference equation (criterion 1), which had used a distribution-free method to obtain the lower fifth percentile of FEV 1 /FVC ratio as the LLN. Results In 525 male patients, using criterion 1 (local internal prediction equation) and defining AFO as FEV 1 /FVC less than LLN, the overall prevalence of AFO was 13.7%: 8.3% in age ≥ 20 to 40 years, 14.0% in age ≥ 40 to 60 years, and 17.8% in age ≥ 60 to 80 years. When the local internal prediction equation was used as the comparison reference, the fixed-ratio methods tended to miss AFO in younger age groups and overdiagnose AFO in old age, while the ERS criteria, which uses an almost lower fifth percentile-equivalent method, showed less of such a trend but still only showed moderate agreement with criterion 1. Conclusions Undiagnosed AFO was prevalent in Hong Kong smokers. Estimated prevalence rates were highly affected by the criteria used to define AFO. The predicted lower fifth percentile values calculated from a local reference equation as the LLN of FEV 1 /FVC ratio should be used for the diagnosis of AFO.

Study objectives The accuracy of reference values of lung function is important for assessment of severity and functional impairment of respiratory diseases. The aim of the study was to establish updated prediction formulae of spirometric parameters for Hong Kong Chinese and to compare the reference values with those derived from other studies in white and Chinese subjects. Design Cross-sectional multicenter study. Setting Lung function laboratories of eight regional hospitals in Hong Kong. Participants Subjects were recruited by random-digit dialing. One thousand one hundred seventy-six subjects who fulfilled recruitment criteria underwent spirometry. Measurements Spirometry was performed according to American Thoracic Society recommendations, and the technique was standardized among the eight participating lung function laboratories. Results Evaluable data of 1,089 (494 men and 595 women) healthy nonsmokers aged 18 to 80 years were analyzed. Age and height were found to be the major determinants of FEV 1 and FVC, with a linear decline of height-adjusted values with age in both sexes. Spirometric values of this population have increased compared to Chinese populations of similar sex, age, and height two decades ago. Reference values derived from white populations were higher than our values by 5 to 19%, and the degree of overestimation varied with age, sex, and lung function parameter. We also demonstrated that the blanket application of correction factors for Asian populations may not be appropriate. In this study cohort, the distribution-free estimation of age-related centiles was more appropriate for the determination of lower limits of normal. Conclusions Our findings underscore the need to use reference values based on updated data derived from local populations or those matched for ethnicity and other sociodemographic characteristics.

Objective: There is so far no consensus on the optimal treatment strategy for the coronavirus-associated severe acute respiratory syndrome (SARS). We aimed to analyse the outcomes of a standard treatment strategy comprising antibiotics, a combination of ribavirin, a 3-week step-down course of corticosteroids, and the possibility of pulsed methylprednisolone rescue in the event of deterioration. Methodology: This was a prospective cohort study performed at a major public-funded hospital in Hong Kong. Eighty-eight World Health Organisation/Centers for Disease Control and Prevention probable cases of SARS (97% laboratory-confirmed) were treated with a standard protocol previously reported. Seventy-one patients treated de novo were analysed in detail with regard to time to clinical stabilization after combination treatment, requirement of additional therapy (pulsed methylprednisolone; assisted ventilation); and final outcomes (recovery, mortality). Results: The mean age was 42. Twenty-one patients (24%) had comorbidities. Three of 71 treated de novo recovered with antibiotics alone. The remaining 68 received combination treatment at a mean of 5.8 days after symptom onset, of whom 30 subsequently required pulsed methylprednisolone rescue (independent predictors: older age and higher LDH) and 18 required assisted ventilation (independent predictors: older age, higher oxygen requirement and creatinine level). Their median time to clinical stabilization was 8.0 days after combination treatment (independent predictor for longer time to stabilization: median age of 41 or above). Common complications were hyperglycaemia (58%), pneumo-mediastinum/thoraces (13%), psychiatric manifestations (7%) and ventilator-associated pneumonia (2%). One patient (1%) died of SARS-related respiratory failure. All-cause mortality was 3.4%, occurring in patients aged > 65 years only. None of the discharged survivors required continuation of oxygen therapy. Conclusions: This standard treatment protocol resulted in overall satisfactory outcomes. Randomized controlled trial is suggested to confirm its efficacy.

Microalbuminuria in diabetes mellitus is a risk factor for cardiovascular disease. We hypothesized that microalbuminuria in type 2 diabetic patients is related to impaired cardiopulmonary function during exercise, and that the severity of impairment is correlated with the degree of microalbuminuria.Twenty of each of the following categories of subjects performed symptom-limited cardiopulmonary exercise testing on a cycle ergometer: (1) type 2 diabetic patients with normoalbuminuria (daily urinary albumin excretion [UAE]30 mg/d); (2) type 2 diabetic patients with microalbuminuria (daily UAE, 30 to 300 mg/d); and (3) normal control subjects.Oxygen consumption (VO(2)) of patients with microalbuminuria was lower than that of control subjects at anaerobic threshold (AT) [p0.001], and was lower than both control subjects (p0.001) and patients with normoalbuminuria (p = 0.015) at peak exercise. There was a progressive worsening in gas exchange efficiency at the lungs, as measured by minute ventilation (VE)/carbon dioxide production (VCO(2)) at AT or DeltaVE/DeltaVCO(2) slope, (p = 0.006 and p = 0.019, respectively) going from control subjects to patients with normoalbuminuria and then to patients with microalbuminuria. Left ventricular ejection fractions and BP were similar in patients with normoalbuminuria and microalbuminuria. More patients with microalbuminuria (n = 9) than with normoalbuminuria (n = 2) demonstrated diastolic dysfunction (p = 0.013). These 11 patients had lower peak VO(2) values (p = 0.001) and higher daily UAE (p = 0.028). An inverse linear relationship was found between peak VO(2) and log(10) daily UAE (r = - 0.57, r(2) = 0.29, p0.001).Abnormalities reflecting reduced oxygen transport and impaired gas exchange efficiency were found during exercise, and were especially profound in patients with microalbuminuria. These changes could be secondary to pulmonary microangiopathy and myocardial interstitial changes. Increases in capillary permeability to proteins may take place in the myocardium as they do in the kidneys, and contribute to impaired myocardial distensibility and hence diastolic dysfunction.

Severe acute respiratory syndrome (SARS) is frequently complicated with acute respiratory failure. In this article, we aim to focus on the management of the subgroup of SARS patients who are critically ill. Most SARS patients would require high flow oxygen supplementation, 20-30% required intensive care unit (ICU) or high dependency care, and 13-26% developed acute respiratory distress syndrome (ARDS). In some of these patients, the clinical course can progress relentlessly to septic shock and/or multiple organ dysfunction syndrome (MODS). The management of critically ill SARS patients requires timely institution of pharmacotherapy where applicable and supportive treatment (oxygen therapy, noninvasive and invasive ventilation). Superimposed bacterial and other opportunistic infections are common, especially in those treated with mechanical ventilation. Subcutaneous emphysema, pneumothoraces and pneumomediastinum may arise spontaneously or as a result of positive ventilatory assistance. Older age is a consistently a poor prognostic factor. Appropriate use of personal protection equipment and adherence to infection control measures is mandatory for effective infection control. Much of the knowledge about the clinical aspects of SARS is based on retrospective observational data and randomized-controlled trials are required for confirmation. Physicians and scientists all over the world should collaborate to study this condition which may potentially threaten human existence.

Ventilator-associated pneumonia is the commonest, yet mostly preventable, infection in mechanically ventilated patients. Successful control of ventilator-associated pneumonia can save hospitalisation cost, and is possible by using a multidisciplinary clinical and administrative approach. The ventilator-associated pneumonia rate should be expressed as the number of ventilator-associated pneumonia days per 1000 ventilator days to take into account the device-utilisation duration for meaningful comparison. Various strategies address the issue, including general infection control measures, body positioning, intubation and mechanical ventilation, oral and gastro-intestinal tract, endotracheal tube, airway pressure, cuff pressure, selective digestive and/or oropharyngeal decontamination, and probiotic or early antibiotic treatment, as well as overall administration at a policy level. The rationale and controversy of these approaches are discussed in this article. The authors suggest that all units treating mechanically ventilated patients should have a ventilator-associated pneumonia prevention protocol in place, and ventilator-associated pneumonia should be seriously considered as a key performance indicator in local intensive care units.

A retrospective study was carried out in a Hong Kong regional hospital with 24-h emergency service, to study the factors associated with shorter time to re-admission after acute exacerbation of chronic obstructive pulmonary disease (COPD). From 1 January 1997 to 31 December 1997, the first admission (index admission) of each patient through the emergency room with COPD/chronic bronchitis/emphysema was included. A total of 551 patients fulfilled the inclusion criteria. The total acute and rehabilitative length of stay (mean ±SD) was 9·41±11·67 days. Within 1 year after discharge, 327 patients (59·35%) were re-admitted at least once. Median time to first re-admission after discharge was 240 days. By Cox regression analysis, the following factors were independently associated with shorter time to re-admission: hospital admission within 1 year before index admission, total length of stay in index admission >5 days, nursing home residency, dependency in self-care activities, right heart strain pattern on electrocardiogram, on high dose inhaled corticosteroid and actual bicarbonate level >25 mmoll −1 . These factors may be relevant in the future planning of healthcare utilization for COPD patients.

OBJECTIVES. To compare three endotracheal tubes for leakage across the cuff (microaspiration) under a comprehensive set of simulated clinical situations. These were the Mallinckrodt TaperGuard (Covidien, US) with a tapered polyvinyl chloride cuff; the KimVent Microcuff (Kimberly-Clark Health Care, US) with a cylindrical polyurethane cuff; and a conventional Portex (Smiths Medical International Ltd, UK) with a globular polyvinyl chloride cuff. DESIGN. A benchtop experimental study. SETTING AND MATERIALS. A silicone cylinder serving as the model trachea was intubated with each of the three endotracheal tubes, one at a time. A total of 20 mL of water were added above the cuff and leakage measured every minute for 20 minutes under five simulated mechanical ventilation scenarios, including different positive end-expiratory pressure levels, and disconnection with and without spontaneous breathing efforts. Each scenario was studied under three cuff pressures of 10, 20 and 30 cm H2O, and then repeated with the application of a continuous suction force of 200 cm H2O, and leakage measured every minute for 3 minutes. RESULTS. The outcome of interest was the cumulative amount of leakage. The Microcuff endotracheal tubes with an ultrathin polyurethane cuff consistently provided the best protection against microaspiration under all simulated clinical situations, followed by TaperGuard with a tapered cuff, and lastly Portex with a globular polyvinyl chloride cuff. Clinical scenarios associated with the greatest leakage were mechanical ventilation with zero positive end-expiratory pressure, circuit disconnection with spontaneous breathing efforts, application of suction, and a low cuff pressure. CONCLUSIONS. Microcuff endotracheal tubes outperformed TaperGuard and Portex endotracheal tubes in preventing microaspiration, which is one of the major mechanisms for ventilator-associated pneumonia.

To identify factors associated with the triage decision for patients classified as Society of Critical Care Medicine (SCCM) Triage Priority 3, and their outcomes.Single-centre, prospective, observational cohort study.General intensive care unit in a tertiary regional hospital, over the 9 months January to September 2007.SCCM Triage Priority 3 patients.All patients were followed up for at least 6 months. Among the 1346 triaged patients, 250 were classified as SCCM Triage Priority 3. Fewer than a third of these (76, 30.4%) were admitted to the ICU. Medical patients were more likely to be rejected than surgical or neurosurgical patients. Those with a poorer physicianpredicted chance of long-term survival were more likely to be rejected than those with a better predicted prognosis. The MPMII0-predicted mortality was higher for those denied ICU admission. Non-postoperative status (odds ratio [OR], 26.3) and physician-predicted risk50% of death within 1 month (OR, 11.8) were independently correlated with denial of ICU admission in a multiple logistic regression analysis. Cox regression analysis showed that independent risk factors for mortality were denial of ICU admission (hazard ratio [HR], 2.80), higher MPMII0-predicted mortality (HR, 1.12 for every 10% increment) and the presence of renal disease as an admission diagnosis (HR, 2.28).For SCCM Triage Priority 3 patients, postoperative status and better physician-predicted prognosis correlated with ICU admission. Patients had lower medium-term survival if they were denied ICU admission, or had higher MPMII0-predicted mortality, or renal disease as the admission diagnosis.

In order to obtain up-to-date information on the pattern of severe acute poisoning and the characteristics and outcomes of these patients, 265 consecutive patients admitted to an intensive care unit in Hong Kong for acute poisoning from January 2000 to May 2008 were studied retrospectively. Benzodiazepine (25.3%), alcohol (23%), tricyclic antidepressant (17.4%), and carbon monoxide (15.1%) were the four commonest poisons encountered. Impaired consciousness was common and intubation was required in 67.9% of admissions, with a median duration of mechanical ventilation of less than 1 day. The overall mortality was 3.0%. Among the 257 survivors, the median lengths of stay in the intensive care unit and acute hospital (excluding days spent in psychiatric ward and convalescent hospital) were less than 1 day and 3 days, respectively. Factors associated with a longer length of stay included age of 65 or older, presence of comorbidity, Acute Physiology and Chronic Health Evaluation II score of 25 or greater, and development of shock, rhabdomyolysis, and aspiration pneumonia, while alcohol intoxication was associated with a shorter stay. This is the largest study of its kind in the Chinese population and provided information on the pattern of severe acute poisoning requiring intensive care admission and the outcomes of the patients concerned.

Background and objective: This study was conducted to define normal reference values and lower limits of normal (LLN) for single-breath carbon monoxide diffusing capacity (DLco) and DLco per unit of alveolar volume (Kco) for Chinese adults in Hong Kong. Methods: Healthy non-smoking men and women aged 18–80 years were recruited by random digit dialling. DLco and Kco were measured according to American Thoracic Society standards. Reference equations were obtained by multiple linear regression; LLN were derived by distribution-free method for estimation of age-related centiles. Results: Tests from 568 subjects (259 men, 309 women) were analysed. DLco declined with age in both genders, and increased with height and the interaction term of height and age in men and women, respectively. Considering Hb values did not improve the reference equations. Kco declined with age and increased with weight in both genders, while height and its interaction term with age were additional determinants in women. The reference DLco was lower than some Caucasian values, and was only explained partially by a smaller body size and alveolar volume in Chinese. The distribution-free method yielded better overall approximation to the fifth percentile compared with the traditional method of determining LLN. Conclusions: The equations for reference values and LLN of diffusing capacity derived in this study are of clinical relevance to Chinese subjects.

Publisher Summary This chapter reviews the response to severe acute respiratory syndrome (SARS), which can serve as a prototype for combating acts of bioterrorism, in the setting of a Hong Kong acute-care hospital. After overcoming the onslaught of SARS, the Hong Kong community has become aware that emerging infections can occur at any time. This is reinforced by the recent avian influenza outbreaks, which act as a reminder of this looming threat. Hospitals have to evaluate their levels of preparedness against bioterrorism, which can simulate infectious disease outbreaks. The priority areas for improvement include community involvement, staff education, improved information technology, disease surveillance, and additional equipment and staff. Multidimensional and flexible-response plans require strong leadership and clear directions to be effective, and such plans must also consider human frailties during great stress, when every resource is stretched to its utmost limit. The chapter concludes by discussing the various infection-control measures implemented in Hong Kong.

The severe acute respiratory syndrome (SARS) caused by the SARSassociated coronavirus (SARS-CoV) has caused a worldwide outbreak in 2003. This chapter will start with a description of the pathogenesis of this disease, followed by a review of the various pharmacological treatments and supportive ventilatory strategies adopted during the outbreak. The principles used to design various combinations of therapeutic agents and treatment modalities will also be described based on the present knowledge.

Summary A series of 31 patients with probable SARS, diagnosed from WHO criteria, were treated according to a treatment protocol consisting of antibacterials and a combination of ribavirin and methylprednisolone. Through experience with the first 11 patients, we were able to finalise standard dose regimens, including pulsed methylprednisolone. One patient recovered on antibacterial treatment alone, 17 showed rapid and sustained responses, and 13 achieved improvement with step-up or pulsed methylprednisolone. Four patients required short periods of non-invasive ventilation. No patient required intubation or mechanical ventilation. There was no mortality or treatment morbidity in this series.