The Cancer Risk among Physicians in Taiwan, a Population-Based Propensity Score Matched Cohort Study.

BACKGROUND: The field of physician health is gaining increasing attention; however, most research and interventions have concentrated on factors such as job stress, mental health, and substance abuse. The risks of major cancers in physicians remain unclear. We used a propensity score-matched analysis to investigate the risk of cancer in physicians relative to the general population who had no healthcare-related professional background. METHODS: Data were obtained from the National Health Insurance system in Taiwan. The physician cohort contained 29,713 physicians, and each physician was propensity score-matched with a person from the general population. RESULTS: The physicians demonstrated a 0.90-fold lower risk of all-cancers (95% confidence interval [CI] = 0.83 - 0.96) when compared with the general population. Female physicians had a higher risk of cancer than male physicians (adjusted hazard ratio [HR] = 1.59; 95% CI = 1.28 - 1.96). Physicians had higher risks of prostate (HR = 1.26; 95% CI = 1.00 - 1.59) and thyroid cancers (HR = 3.16; 95% CI = 1.69 - 5.90) when compared with the general population. CONCLUSION: Physicians have lower rates of overall cancer risk than the general population. Female physicians have higher cancer risks than male physicians. Male physicians have higher risks of thyroid and prostate cancer relative to the general population.

Correction: Superior upconversion fluorescence dopants for highly efficient deep-blue electroluminescent devices.

[This corrects the article DOI: 10.1039/C6SC00100A.].

Superior upconversion fluorescence dopants for highly efficient deep-blue electroluminescent devices.

In this study, we revealed a new approach for the development of new triplet-triplet annihilation (TTA) materials with highly efficient deep-blue fluorescence via the incorporation of a styrylpyrene core and an electron-donating group. The resulting deep-blue emitters (PCzSP, DFASP, and DPASP) exhibit intramolecular charge transfer emissions with remarkably high emission quantum yields. The electroluminescent devices based on these three fluorophores as dopants using CBP as a host exhibit very high device efficiencies; in particular, the DPASP-doped device reveals an extremely high EQE of 12%, reaching the limit of a TTA-based device. The EL characteristics of DPASP-doped CBP-based devices at various doping concentrations (0-5%) suggest that the dopant DPASP is responsible for the TTA-type delayed fluorescence in the device; no delayed fluorescence was observed for the device using CBP as the host emitter. Moreover, when using DMPPP with ambipolar characteristics as the host, the deep-blue DPASP-doped device also gives outstanding performance with an EQE of nearly 11% with an extremely small efficiency roll-off, which was ascribed to the excellent charge balance in the emitting layer of the EL device. The TTA process of the SP-based dopants accounts significantly for the superior efficiencies of the EL devices.

A high-resolution computed tomography-based scoring system to differentiate the most infectious active pulmonary tuberculosis from community-acquired pneumonia in elderly and non-elderly patients.

OBJECTIVE: The objective of this study was to use high-resolution computed tomography (HRCT) imaging to predict the presence of smear-positive active pulmonary tuberculosis (PTB) in elderly (at least 65 years of age) and non-elderly patients (18-65 years of age). METHODS: Patients with active pulmonary infections seen from November 2010 through December 2011 received HRCT chest imaging, sputum smears for acid-fast bacilli and sputum cultures for Mycobacterium tuberculosis. Smear-positive PTB was defined as at least one positive sputum smear and a positive culture for M. tuberculosis. Multivariate logistic regression analyses were performed to determine the HRCT predictors of smear-positive active PTB, and a prediction score was developed on the basis of receiver operating characteristic curve analysis. RESULTS: Of 1,255 patients included, 139 were diagnosed with smear-positive active PTB. According to ROC curve analysis, the sensitivity, specificity, positive predictive value, negative predictive value, false positive rates and false negative rates were 98.6 %, 95.8 %, 78.5 %, 99.8 %, 4.2 % and 1.4 %, respectively, for diagnosing smear-positive active PTB in elderly patients, and 100.0 %, 96.9 %, 76.5 %, 100.0 %, 3.1 % and 0.0 %, respectively, for non-elderly patients. CONCLUSIONS: HRCT can assist in the early diagnosis of the most infectious active PTB, thereby preventing transmission and minimizing unnecessary immediate respiratory isolation. KEY POINTS: • HRCT can assist in the early diagnosis of the infectious active PTB • HRCT imaging is useful to predict the presence of smear-positive active PTB • Predictions from the HRCT imaging are valid even before sputum smear or culture results.

A high resolution computer tomography scoring system to predict culture-positive pulmonary tuberculosis in the emergency department.

This study evaluated the use of high-resolution computed tomography (HRCT) to predict the presence of culture-positive pulmonary tuberculosis (PTB) in adult patients with pulmonary lesions in the emergency department (ED). The study included a derivation phase and validation phase with a total of 8,245 patients with pulmonary disease. There were 132 patients with culture-positive PTB in the derivation phase and 147 patients with culture-positive PTB in the validation phase. Imaging evaluation of pulmonary lesions included morphology and segmental distribution. The post-test probability ratios between both phases in three prevalence areas were analyzed. In the derivation phase, a multivariate analysis model identified cavitation, consolidation, and clusters/nodules in right or left upper lobe (except anterior segment) and consolidation of the superior segment of the right or left lower lobe as independent positive factors for culture-positive PTB, while consolidation of the right or left lower lobe (except superior segment) were independent negative factors. An ideal cutoff point based on the receiver operating characteristic (ROC) curve analysis was obtained at a score of 1. The sensitivity, specificity, positivity predictive value, and negative predictive value from derivation phase were 98.5% (130/132), 99.7% (3997/4008), 92.2% (130/141), and 99.9% (3997/3999). Based on the predicted positive likelihood ratio value of 328.33 in derivation phase, the post-test probability was observed to be 91.5% in the derivation phase, 92.5% in the validation phase, 94.5% in a high TB prevalence area, 91.0% in a moderate prevalence area, and 76.8% in moderate-to-low prevalence area. Our model using HRCT, which is feasible to perform in the ED, can promptly diagnose culture-positive PTB in moderate and moderate-to-low prevalence areas.

Prevalence of asymptomatic peripheral arterial disease and related risk factors in younger and elderly patients in Taiwan.

We determined the prevalence of asymptomatic peripheral arterial disease (PAD) and cardiovascular risk factors in Taiwan. Ambulatory participants (n = 1915) without symptoms of PAD were enrolled (mean age of 61.2 years). The ankle-brachial index (ABI) was used to detect the PAD (ABI < 0.90). The overall prevalence of asymptomatic PAD was 5.4% (2.8% in the younger participants [<65 years of age, n = 1021] and 8.4% in the elderly participants [≥65 years of age, n = 894]). Younger participants with asymptomatic PAD had a significantly higher rate of hypertension (55.2% vs 30%) and obesity (31% vs 13.3%) than those without asymptomatic PAD (P < .05). Elderly participants with asymptomatic PAD had a significantly higher rate of diabetes mellitus (36% vs 21.2%) and hypertension (69.3% vs 55.4%) than those without asymptomatic PAD (P < .05). Asymptomatic PAD is prevalent among elderly Taiwanese individuals. Overall, age was the strongest risk factor for the development of asymptomatic PAD.

Prevalence and risk factors of asymptomatic peripheral arterial disease in patients with COPD in Taiwan.

AIM: Chronic obstructive pulmonary disease (COPD) is an independent risk factor for cardiovascular morbidity and mortality. The aim of this study was to determine the prevalence of asymptomatic peripheral arterial disease (PAD) and the associated risk factors for patients with COPD. METHODS: This prospective cross-sectional study enrolled 427 COPD patients (mean age: 70.0 years) without PAD symptoms consecutively. Demographic data, lung function and cardiovascular risk factors were recorded. The ankle-brachial index (ABI) was used to detect PAD (ABI<0.90). RESULTS: The overall prevalence of asymptomatic PAD in the COPD patients was 8% (2.5% in the younger participants (<65 years of age, n = 118) and 10% in the elderly participants (≥65 years of age, n = 309). The COPD patients with asymptomatic PAD had a significantly higher rate of hyperlipidemia (47.1% vs. 10.4%) and hypertension (79.4% vs. 45.8%) than those without asymptomatic PAD (p<0.05). There was no significant difference in lung function (forced vital capacity and forced expiratory volume in one second) between the two groups. In multivariate logistic regression, hyperlipidemia was the strongest independent factor for PAD (odds ratio (OR): 6.89, p<0.005), followed by old age (OR: 4.80), hypertension (OR: 3.39) and smoking burden (pack-years, OR: 1.02). CONCLUSIONS: The prevalence of asymptomatic PAD among COPD patients in Taiwan is lower than in Western countries. Hyperlipidemia, old age, hypertension, and smoking burden were the associated cardiovascular risk factors. However, there was no association between lung function and PAD in the COPD patients.

Improved survival for an integrated system of reduced intensive respiratory care for patients requiring prolonged mechanical ventilation.

BACKGROUND: The introduction of reduced respiratory care may lead to worse long-term outcomes for patients undergoing prolonged mechanical ventilation (PMV) for more than 21 days. The objective of this study was to determine the survival for an integrated system of reduced intensive respiratory care (ISRIRC) by the Taiwan Bureau of National Health Insurance, in patients requiring PMV. METHODS: A 10-year retrospective study was performed in a 1,000-bed teaching hospital in Taiwan. A total of 633 consecutive PMV patients transferred from the hospital between 1998 and 2007 were enrolled. Medical records were reviewed to collect the clinical data, which were linked to the National Death Certification Database to ascertain subject survival. Kaplan-Meier estimates were performed, and a Cox proportional hazards model was constructed. We further conducted a corroboration study and retrieved a systematically randomized nationwide sample of PMV subjects with combined septicemia and shock, and compared the survival functions of those who were treated before and after the integrated system, including 228 and 2,677 subjects, respectively. RESULTS: The survival rates at 3 months, 6 months, and 1 year were 60.0%, 44.0%, and 30.0%, respectively. The 1-year survival rates of the subjects before and after ISRIRC were 21.0% and 37.2%, respectively (P = .04). The factors associated with better survival were younger age, absence of cirrhosis, and establishment of the ISRIRC. A comparison of the 4-year survival in the larger random sample of PMV subjects with combined septicemia and shock before and after ISRIRC also showed a significant improvement. CONCLUSIONS: With the improvement of PMV technology in the early 2000s, the establishment of ISRIRC seems to be associated with an improved survival rate for subjects under PMV.

Cost per QALY (quality-adjusted life year) and lifetime cost of prolonged mechanical ventilation in Taiwan.

INTRODUCTION: Patients who require prolonged mechanical ventilation (PMV) are increasing and producing financial burdens worldwide. This study determines the cost per QALY (quality-adjusted life year), out-of-pocket expenses, and lifetime costs for PMV patients stratified by underlying diseases and cognition levels. METHODS: A nationwide sample of 50,481 patients with continual mechanical ventilation for more than 21 days was collected during 1997-2007. After stratifying the patients according to specific diagnoses, a latent class analysis (LCA) was performed to categorise PMV patients with multiple co-morbidities into several homogeneous groups. The survival functions were estimated for individual groups using the Kaplan-Meier method and extrapolated to 300 months through a semi-parametric method. The survival functions were adjusted using an EQ-5D utility value derived from a convenience sample of 142 PMV patients to estimate quality-adjusted life expectancies (QALE). Another convenience sample of 165 patients was used to estimate the out-of-pocket expenses. The lifetime expenditures paid by the single-payer National Health Insurance (NHI) system and patients' families were estimated by multiplying average monthly expenditures by the survival probabilities and summing the values over lifetime. RESULTS: PMV therapy costs more than 100,000 U.S. dollars (USD) per QALY for all patients with poor cognition. For patients with partial cognition, PMV therapy costs less than 56,000 USD per QALY for those with liver cirrhosis, intracranial or spinal cord injuries, and 57,000-69,000 USD for patients with multiple co-morbidities under age of 65. The average lifetime cost of PMV was usually below 56,000 USD. The out-of-pocket expenses were often more than one-third of the total cost of treatment. CONCLUSIONS: PMV treatment for patients with poor cognition would cost more than 5 times Taiwan's GDP (gross domestic products), or less cost-effective. The out-of-pocket expenses for PMV provision should also be considered in policy decision.

Idiopathic pulmonary fibrosis in Taiwan - a population-based study.

BACKGROUND: This study took advantage of a large population-based database of the Taiwan National Health Insurance (NHI) to investigate the epidemiology of idiopathic pulmonary fibrosis (IPF) in Taiwan. METHODS: This is a retrospective cohort study based on secondary analysis of prospectively collected data in the NHI system and governmental data on death registry in Taiwan during 1997-2007. By using the broad and narrow definitions for IPF, we estimated incidence and prevalence rates of IPF, and its associated clinical outcomes. RESULTS: The estimates of annual IPF incidence rates became more stable after 2000, ranging between 0.9 and 1.6 cases per 100,000 persons. The prevalence rates became more than twofold from 2000 to 2007 (from 2.8 to 6.4 cases per 100,000 persons for the broad definition, and from 2.0 to 4.9 cases per 100,000 persons for the narrow definition). Men of age older than 75 years had markedly higher incidence and prevalence rates than other groups. Around 40% of all incidences and about 30% of prevalent cases occurred in this population group. The median survival time after IPF diagnosis was 0.9 year (interquartile range (IQR), 0.2-2.5 years) and 0.7 year (IQR, 0.1-2.3 years) for the broad and narrow definitions, respectively. Progression of IPF was the leading cause of death, followed by cancer. CONCLUSIONS: In Taiwan, elderly men were the major group suffering from IPF. Survival time was short after IPF diagnosis, and the poor survival was largely attributable to quick IPF progression after diagnosis.

Outcomes of prolonged mechanic ventilation: a discrimination model based on longitudinal health insurance and death certificate data.

BACKGROUND: This study investigated prognosis among patients under prolonged mechanical ventilation (PMV) through exploring the following issues: (1) post-PMV survival rates, (2) factors associated with survival after PMV, and (3) the number of days alive free of hospital stays requiring mechanical ventilation (MV) care after PMV. METHODS: This is a retrospective cohort study based on secondary analysis of prospectively collected data in the national health insurance system and governmental data on death registry in Taiwan. It used data for a nationally representative sample of 25,482 patients becoming under PMV (> = 21 days) during 1998-2003. We calculated survival rates for the 4 years after PMV, and adopted logistic regression to construct prediction models for 3-month, 6-month, 1-year, and 2-year survival, with data of 1998-2002 for model estimation and the 2003 data for examination of model performance. We estimated the number of days alive free of hospital stays requiring MV care in the immediate 4-year period after PMV, and contrasted patients who had low survival probability with all PMV patients. RESULTS: Among these patients, the 3-month survival rate was 51.4%, and the 1-year survival rate was 31.9%. Common health conditions with significant associations with poor survival included neoplasm, acute and unspecific renal failure, chronic renal failure, non-alcoholic liver disease, shock and septicaemia (odd ratio < 0.7, p < 0.05). During a 4-year follow-up period for patients of year 2003, the mean number of days free of hospital stays requiring MV was 66.0 in those with a predicted 6-month survival rate < 10%, and 111.3 in those with a predicted 2-year survival rate < 10%. In contrast, the mean number of days was 256.9 in the whole sample of patients in 2003. CONCLUSIONS: Neoplasm, acute and unspecific renal failure, shock, chronic renal failure, septicemia, and non-alcoholic liver disease are significantly associated with lower survival among PMV patients. Patients with anticipated death in a near future tend to spend most of the rest of their life staying in hospital using MV services. This calls for further research into assessing PMV care need among patients at different prognosis stages of diseases listed above.

Life expectancies and incidence rates of patients under prolonged mechanical ventilation: a population-based study during 1998 to 2007 in Taiwan.

INTRODUCTION: The present study examined the median survival, life expectancies, and cumulative incidence rate (CIR) of patients undergoing prolonged mechanical ventilation (PMV) stratified by different underlying diseases. METHODS: According to the National Health Insurance Research Database of Taiwan, there were 8,906,406 individuals who obtained respiratory care during the period from 1997 to 2007. A random sample of this population was performed, and subjects who had continuously undergone mechanical ventilation for longer than 21 days were enrolled in the current study. Annual incidence rates and the CIR were calculated. After stratifying the patients according to their specific diagnoses, latent class analysis was performed to categorise PMV patients with multiple co-morbidities into several groups. The life expectancies of different groups were estimated using a semiparametric method with a hazard function based on the vital statistics of Taiwan. RESULTS: The analysis of 50,481 PMV patients revealed that incidence rates increased as patients grew older and that the CIR (17 to 85 years old) increased from 0.103 in 1998 to 0.183 in 2004 before stabilising thereafter. The life expectancies of PMV patients suffering from degenerative neurological diseases, stroke, or injuries tended to be longer than those with chronic renal failure or cancer. Patients with chronic obstructive pulmonary disease survived longer than did those co-morbid with other underlying diseases, especially septicaemia/shock. CONCLUSIONS: PMV provides a direct means to treat respiratory tract diseases and to sustain respiration in individuals suffering from degenerative neurological diseases, and individuals with either of these types of conditions respond better to PMV than do those with other co-morbidities. Future research is required to determine the cost-effectiveness of this treatment paradigm.

Bowel-cleansing methods affecting PET-CT image interpretation.

BACKGROUND: The purpose of this study is to evaluate bowel-cleansing methods for colonic preparation, based on the findings of PET-computed tomographic (CT) scans. METHODS: A total of 175 patients were enrolled in this study. Patients with medical histories of colorectal cancer, abdominal operation, or abdominal malignancies were excluded from this study. The patients were divided into three groups according to the three kinds of bowel-cleansing methods used: (i) no laxatives or dietary restriction (control group), (ii) dietary restriction (low-residue diet), and (iii) a combination of contact laxatives (Dulcolax) and dietary restriction (low-residue diet). Colonic standardized uptake value data were recorded. The hot spots that influenced the interpretation of images or the localization of true lesions were classified as positive (+), whereas data that did not influence clinical diagnosis were classified as negative (-). RESULTS: In the first group, 22.2% of the patients with positive colonic hot spots were detected in whole-body PET-CT scans. In the second group, a 34.9% positive rate of colonic hot spots was visible. In the third group, a 73.5% positive rate was detected. The positive rate in the third group is significantly higher than the percentages detected in the first and the second groups (P<0.01). CONCLUSION: The findings indicated that a low-residue diet is not beneficial to colonic preparation. Moreover, contact laxatives cause diagnostic confusion when PET-CT images are interpreted. Therefore, although PET-CT scans are capable of adding precision to functional imaging, and to focal localization, the researchers concluded that avoiding contact laxatives is necessary to decrease intestinal artifacts.

Estimation of quality-adjusted life expectancy in patients under prolonged mechanical ventilation.

OBJECTIVES: The purpose of this study was to estimate the quality-adjusted life expectancy (QALE) and the expected lifetime utility loss of patients with prolonged mechanical ventilation (PMV). METHODS: PMV was defined as more than 21 days of mechanical ventilation. A total of 633 patients fulfilled this definition and were followed for 9 years (1998-2007) to obtain their survival status. Quality of life of 142 patients was measured with the EuroQol five-dimensional (EQ-5D) questionnaire during the period 2008 to 2009. The survival probabilities for each time point were adjusted with a utility measurement of quality of life and then extrapolated to 300 months to obtain the QALE. We compared the age-, gender-matched reference populations to calculate the expected lifetime utility loss. RESULTS: The average age of subjects was 76 years old. The life expectancy and loss of life expectancy were 1.95 years and 8.48 years, respectively. The QALE of 55 patients with partial cognitive ability and the ability to respond was 0.58 quality-adjusted life years (QALY), whereas the QALEs of 87 patients with poor consciousness were 0.28 and 0.29 QALY for the EQ-5D measured by family caregivers and nurses, respectively. The loss of QALE for PMV patients was 9.87 to 10.17 QALY, corresponding to a health gap of 94% to 97%. CONCLUSIONS: Theses results of poor prognosis would provide stakeholders evidence for communication to facilitate clinical decisions. The estimation may be used in future studies to facilitate the cost-effectiveness and reduction of the health gap.

Measurement of quality of life using EQ-5D in patients on prolonged mechanical ventilation: comparison of patients, family caregivers, and nurses.

PURPOSE: This study reports how QOL (quality of life) assessments differ between patients on prolonged mechanical ventilation (PMV) and their proxies (family caregivers and nurses). METHODS: We enrolled consecutive subjects on PMV for more than 21 days from five institutions. We conducted QOL assessments using the Taiwanese version of the EQ-5D in face-to-face interviews. Direct caregivers (family members and nurses) also completed the EQ-5D from the patient's point of view. RESULTS: For 55 of the 142 enrolled patients who were able to assess their QOL, we recruited 44 patient-family caregiver pairs, 53 patient-nurse pairs, and 42 family caregiver-nurse pairs. There were 81 family caregiver-nurse pairs out of 87 patients with poor cognition. The agreement between patient-family caregiver pairs was generally higher than that of patient-nurse pairs. As the proportions of exact agreement between family caregivers and nurses for patients with poor cognition were 98-99% for observable dimensions of mobility, self-care, and usual activities, they lead to a minimal difference in the final values. CONCLUSIONS: QOL assessments from family caregivers agreed more closely with patients than did those from nurses using EQ-5D evaluations for patients with clear cognition, but either proxy was acceptable for rating PMV patients with poor cognition.

Chest wall abscess due to Prevotella bivia.

Prevotella bivia is associated with pelvic inflammatory disease. A 77-year-old man developed a rapidly growing chest wall abscess due to P. bivia within days. He underwent surgical resection of the infected area; his postoperative course was uneventful. This is the first case of chest wall abscess due to P. bivia infection. Its correct diagnosis cannot be underestimated because fulminant infections can occur in aged or immunocompromised patients if treated incorrectly. Prompt, appropriate surgical management, and antibiotic therapy affect treatment outcome.

Predictors of successful noninvasive ventilation treatment for patients suffering acute respiratory failure.

BACKGROUND: To identify predictors of successful noninvasive ventilation (NIV) treatment for patients with acute respiratory failure. METHODS: This was a prospective intervention study of the intensive care unit of a teaching hospital in Chia-Yi, Taiwan. Patients were enrolled if they had acute respiratory failure and had been admitted to the intensive care unit of our hospital between October 1, 2004 and September 30, 2005 inclusively. RESULTS: All 86 patients who satisfied the study's inclusion criteria agreed to participate in the study, and each patient was followed-up until the discontinuation of NIV treatment or their death. We measured the Acute Physiology and Chronic Health Evaluation (APACHE) II score prior to their treatment and also conducted serial measurements of respiratory rate (RR), tidal volume, rapid shallow breathing index, maximal inspiratory pressure (PImax), and maximal expiratory pressure (PEmax) prior to, and 30 minutes and 60 minutes subsequent to NIV treatment (denoted by, respectively, the subscripted numbers 0, 30 and 60). NIV treatment was determined as being successful for 55 patients (the success group, for which individuals endotracheal intubation was avoided) and as being a failure for 31 patients (the failure group). APACHE II scores prior to treatment, PImax30 (PImax 30 minutes subsequent to NIV), RR30 (RR 30 minutes subsequent to NIV), and RR60 (RR 60 minutes subsequent to NIV) were all significantly lower for the success group than for the failure group. The success group also had significantly better values for RR during the first 30 minutes of NIV treatment and for PEmax during the first 60 minutes of NIV treatment compared to individuals from the failure group. CONCLUSION: APACHE II scores recorded prior to NIV treatment, PImax30, RR30, RR60, as well as improvements to RR during the first 30 minutes of NIV treatment and to PEmax during the first 60 minutes of NIV treatment were predictors of successful NIV treatment for patients suffering from acute respiratory failure. Such parameters may be helpful in selecting patients to receive NIV treatment and also for deciding when early termination of the treatment is appropriate.

Video-assisted thoracoscopic surgery (VATS) for bilateral primary spontaneous pneumothorax.

OBJECTIVE: To review our experience of the treatment of bilateral primary spontaneous pneumothorax (PSP) by video-assisted thoracoscopic surgery (VATS). MATERIALS AND METHODS: Retrospective chart review was followed by an on-clinic or telephone interview. Patients were cared for by one thoracic surgeon in four medical centers or community hospitals in Northern and Central Taiwan. Thirteen patients with bilateral PSP underwent bilateral VATS simultaneously or sequentially from July 1994 to December 2005. RESULTS: Twelve males and one female, with age ranging from 15 to 36 years (mean 23.1 years), were treated with VATS for bilateral PSP, under the indications of bilateral pneumothoracis simultaneously (n=4) or sequentially (n=9). The interval between the first and second contra-lateral VATS procedure for non-simultaneous PSP patients ranged from 7 d to 6 years. Eleven of 13 patients (84.6%) had prominent pulmonary bullae/blebs, and underwent bullae resection with mechanical or chemical pleurodesis. The mean operative time was (45.6+/-18.3) min (range 25 approximately 96 min) and (120.6+/-28.7) min (range 84 approximately 166 min) respectively for the non-simultaneous (second VATS for the recurrence of contralateral side after first VATS) and simultaneous (bilateral VATS in one operation) procedures. There was no postoperative mortality. However, prolonged air leakage (>7 d) occurred in one patient (7.7%) who recovered after conservative treatment. The mean duration of chest tube drainage was 3.1 d and the median follow up period was 3.4 years. CONCLUSIONS: VATS is a safe and effective procedure in the treatment of bilateral PSP. Bilateral VATS is only recommended for patients with simultaneously bilateral PSP, because the incidence of recurrence, even with visible bullae, was not so high in my group and in some previous literature. Bilateral VATS in a supine position should only be used in selective cases, because of possible pleural adhesion or hidden bullae on the posterior side.