Meng-Jer Hsieh

Prediction of fluid responsiveness in acute respiratory distress syndrome patients ventilated with low tidal volume and high positive end-expiratory pressure*

Objective:Dynamic preload indicators with pulse pressure variation and stroke volume variation are superior to static indicators for predicting fluid responsiveness in mechanically ventilated patients. However, they are influenced by tidal volume and the level of positive end-expiratory pressure. The present study was designed to evaluate the clinical applicability of pulse pressure variation and stroke volume variation in predicting fluid responsiveness on acute respiratory distress syndrome patients ventilated with protective strategy (low tidal volume and high positive end-expiratory pressure). Design:Prospective, observational study. Setting:A 20-bed medical intensive care unit of a tertiary medical center. Patients:Twenty-two sedated and paralyzed early acute respiratory distress syndrome patients. Interventions:After being enrolled, central venous pressure, pulmonary capillary wedge pressure, and cardiac output index were obtained from a pulmonary artery catheter (OptiQ SvO2/CCO catheter), and intrathoracic blood volume, global end-diastolic volume, stroke volume variation, and pulse pressure variation were recorded from a PiCCOplus monitor. The whole set of hemodynamic measurements was performed before and after volume expansion with 500 mL hydroxyethyl starch (10% pentastarch 200/0.5). Measurements and Main Results:Cardiac output index, central venous pressure, pulmonary capillary wedge pressure, global end-diastolic volume, and intrathoracic blood volume significantly increased, and pulse pressure variation and stroke volume variation significantly decreased after volume expansion. Baseline pulse pressure variation significantly correlated with volume expansion-induced absolute changes (r = .62), or percent changes in cardiac output index (r = .75) after volume expansion. The area under the receiver operating characteristic curve was the highest for pulse pressure variation (area under the receiver operating characteristic curve = 0.768) than other indicators. The threshold value for baseline pulse pressure variation greater than 11.8% predicted a significant positive response to volume expansion with a sensitivity of 68% and a specificity of 100%. Conclusions:Baseline pulse pressure variation accurately predicted the fluid responsiveness in early acute respiratory distress syndrome patients. Roughly, a baseline pulse pressure variation greater than the threshold value of 12% is associated with a significant increase in cardiac output index after the end of volume expansion.

Salvage surgery after failed chemoradiotherapy in squamous cell carcinoma of the esophagus.

AIMS To investigate the survival benefit and preoperative risk factors for hospital mortality of salvage surgery in esophageal cancer patients who had locoregional residual/recurrent tumor after definitive chemoradiotherapy. METHODS We retrospectively reviewed the esophageal cancer patients who presented at our hospital from 1997 to 2004. Forty-seven patients who had squamous cell cancer and developed locoregional recurrent/persistent disease after primary definitive chemoradiotherapy were elected. Twenty-seven of them received salvage esophagectomy (group 1) and the other 20 underwent non-operative treatment only (group 2). In order to assess the surgery-related mobility and mortality in group 1, 191 patients who received neoadjuvant chemoradiotherapy followed by operation during the same time period were also enrolled (group 3). RESULTS The 5-year overall survival of group 1 patients was 25.4%. In contrast, all of the patients in the group 2 died within 16.7 months. The difference was statistically significant (p=0.0029). In comparison with group 3, group 1 patients had significantly more surgery-related complications and hospital mortality. In univariate analysis for preoperative risk factors, a low albumin or hemoglobulin level was associated with high hospital mortality in group 1 (p=0.004 and 0.003, respectively). After multivariate analysis, only the low albumin level remained borderline significance. As for disease specific survival after salvage surgery, R0 resection was the only independent prognosticator (p=0.049). CONCLUSION Salvage surgery provides survival benefit in esophageal cancer patients with locoregional persistent or recurrent disease after primary definitive chemoradiotherapy. Preoperative albumin and hemoglobulin levels are associated with hospital mortality and may aid in selecting suitable patient for salvage surgery.

Open lung biopsy in early-stage acute respiratory distress syndrome.

IntroductionAcute respiratory distress syndrome (ARDS) has heterogeneous etiologies, rapid progressive change and a high mortality rate. To improve the outcome of ARDS, accurate diagnosis is essential to the application of effective early treatment. The present study investigated the clinical effects and safety of open lung biopsy (OLB) in patients with early-stage ARDS of suspected non-infectious origin.MethodsWe undertook a retrospective study of 41 patients with early-stage ARDS (defined as one week or less after intubation) who underwent OLB in two medical intensive care units of a tertiary care hospital from 1999 to 2005. Data analyzed included baseline characteristics, complication rate, pathological diagnoses, treatment alterations, and hospital survival.ResultsThe age of patients was 55 ± 17 years (mean ± SD). The average ratio of arterial partial pressure of oxygen (PaO2) to fraction of inspired oxygen (FiO2) was 116 ± 43 mmHg (mean ± SD) at biopsy. Seventeen patients (41%) were immunocompromised. Postoperative complications occurred in 20% of patients (8/41). All biopsies provided a pathological diagnosis with a diagnostic yield of 100%. Specific pathological diagnoses were made for 44% of patients (18/41). Biopsy findings led to an alteration of treatment modality in 73% of patients (30/41). The treatment alteration rate was higher in patients with nonspecific diagnoses than in patients with specific diagnoses (p = 0.0024). Overall mortality was 50% (21/41) and was not influenced by age, gender, pre-OLB oxygenation, complication rate, pathological results, and alteration of treatment. There was no surgery-related mortality. The survival rate for immunocompromised patients was better than that for immunocompetent patients (71% versus 33%; p = 0.0187) in this study.ConclusionOur retrospective study suggests that OLB was a useful and acceptably safe diagnostic procedure in some selected patients with early-stage ARDS.

Predictors of successful weaning from prolonged mechanical ventilation in Taiwan.

BACKGROUND For adult patients on prolonged mechanical ventilation (PMV, >/=21 days), successful weaning has been attributed to various factors. The purpose of this study was to describe patient outcomes, weaning rates and factors in successful weaning at a hospital-based respiratory care center (RCC) in Taiwan. METHODS AND RESULTS This was a retrospective observational study performed in a 24-bed RCC over six years. A total of 1307 patients on PMV were included in the study. The overall survival rate was 62%. Fifty-six percent of patients were successfully weaned. Unsuccessfully weaned patients had higher MICU transfer rates, higher Acute Physiology and Chronic Health Evaluation II scores, longer duration of RCC stay, higher rates of being bed-ridden prior to admission, increased hemodialysis rates, higher modified Glasgow Coma Scale scores, higher rapid shallow breathing index, lower inspiratory pressure at residual volume (PImax) and lower blood urea nitrogen (BUN) and creatinine levels. Factors found to be associated with unsuccessful weaning were length of RCC stay (OR=1.04, P<0.001), modified GCS score (OR=0.93, P<0.046), PImax (OR=0.97, P<0.001), serum albumin concentration (OR=0.62, P<0.023) and BUN level (OR=1.01, P<0.002). CONCLUSION High rates of ventilator independence can be achieved in an RCC setting as an alternative to ICU care. Factors associated with unsuccessful weaning included longer duration of RCC stay, elevated BUN levels and lower modified GCS scores, serum albumin and PImax levels.

Effects of high-intensity exercise training in a pulmonary rehabilitation programme for patients with chronic obstructive pulmonary disease.

Background and objectives:  The benefits of pulmonary rehabilitation for patients with COPD depend on the intensity of training. Traditional pulmonary rehabilitation programmes (PRPs) do not consistently achieve high‐intensity training and have variable training effects. This study examined the effects of high‐intensity exercise training on cardiac and pulmonary function in COPD patients.

The 23-valent pneumococcal polysaccharide vaccine is effective in elderly adults over 75 years old—Taiwan's PPV vaccination program

BACKGROUND Pneumococcal infection is a serious cause of mortality and morbidity in the elderly. A nationwide pneumococcal polysaccharide vaccine (PPV) program for elderly adults aged 75 years and older was conducted in Taiwan in 2008. The efficacy of the PPV in this very elderly population was evaluated. METHODS The data were analyzed using the Taiwan National Health Insurance Research Database (NHIRD), the cause-of-death registration database and the invasive pneumococcal disease (IPD) notification database of Taiwans Ministry of Health and Welfare. The efficacy of PPV administration in this very elderly population was evaluated using multivariate logistic regression after propensity score matching (PSM). The rates of IPD, death from IPD, pneumonia hospitalization, death from pneumonia, and all-cause mortality were compared for those who did and did not receive the PPV. RESULTS Among the 1078,955 eligible people, 318,257 (29.5%) received the PPV, and 760,698 (70.5%) were not vaccinated. Using PSM to adjust for confounding factors, including age, gender, influenza vaccination status, associated chronic diseases and health care utilization, those who received the PPV had significantly lower odds ratios (ORs) for IPD (OR=0.24, 95% CI=0.123-0.461, p<0.001), death from IPD (OR=0.09, 95% CI=0.011-0.704, p<0.022, p<0.001), pneumonia hospitalization (OR=0.40, 95% CI=0.395-0.415, p<0.001), death from pneumonia (OR=0.07, 95% CI=0.059-0.082, p<0.001), and all-cause mortality (OR=0.07, 95% CI=0.069-0.072, p<0.001) compared with those who were not vaccinated. CONCLUSIONS PPV vaccination in the previous year was associated with a 60% reduction in pneumonia hospitalization, a 76% reduction in IPD, and a greater than 90% reduction in death from pneumonia, IPD and all causes among people over 75 years old in Taiwan. Data from subsequent years in Taiwan and similar populations elsewhere are needed to evaluate the contribution of underlying variations in the mortality rate and the confounding effects of prior disease severity to these findings.

Effects of hydroxyethyl starch resuscitation on extravascular lung water and pulmonary permeability in sepsis-related acute respiratory distress syndrome.

Objective:Hydroxyethyl starch (HES) has greater volume expansion effect and longer intravascular persistence than crystalloids. HES also decreases microvascular permeability and capillary leakage by biophysically plugging endothelial leaks, exerting an anti-inflammatory effect, and decreasing activation of endothelial cells. The aim of our study was to determine whether medium molecular weight HES (pentastarch) resuscitation in the early stage of acute respiratory distress syndrome (ARDS) simultaneously increases cardiac output without worsening pulmonary edema and whether it attenuates pulmonary vascular permeability. Design:Prospective observational study. Setting:Twenty-bed medical intensive care unit of a tertiary medical center. Patients:Twenty patients with early-stage ARDS. Intervention:Volume expansion with a 500-mL infusion of 10% pentastarch (HES 200/0.5) at a rate of 10 mL/kg/hr. Measurements and Main Results:Baseline hemodynamics including systemic and pulmonary artery blood pressures, central venous pressure, pulmonary artery occlusion pressure, and cardiac output were obtained from an online HP Component Monitoring System and a pulmonary artery catheter. Intrathoracic blood volume (ITBV), global end-diastolic volume, extravascular lung water (EVLW), and pulmonary vascular permeability (EVLW/ITBV) were measured with a PiCCOplus monitor. Hemodynamic measurements were repeated immediately and 2, 4, and 6 hours after volume expansion. Pentastarch loading significantly increased central venous pressure, pulmonary artery occlusion pressure, pulmonary arterial pressures, and cardiac output. Pulmonary mechanics, venous admixtures, and EVLW values remained unchanged throughout the study. EVLW/ITBV significantly decreased immediately after the pentastarch infusion. Conclusions:In patients with early ARDS, pentastarch resuscitation significantly improved their hemodynamics and cardiac output without worsening pulmonary edema and pulmonary mechanics. It even attenuated pulmonary vascular permeability.

Outcome of Hematopoietic Stem Cell Recipients Who Were Mechanically Ventilated and Admitted to Intensive Care Units

BACKGROUND/PURPOSE To evaluate the ICU mortality rate of mechanically ventilated hematopoietic stem cell transplantation (HSCT) recipients and to identify the factors that were associated with ICU mortality. The impact of surgical lung biopsy (SLB) in patients with unexplained pulmonary infiltrates was also evaluated. METHODS Forty-one mechanically ventilated HSCT recipients admitted to the ICU during the study period were enrolled. The medical records were reviewed and data at ICU admission were analyzed. Data were compared between ICU survivors and nonsurvivors. The pathologic findings of SLB and the resulting impact on treatment were analyzed. RESULTS Eight patients (19.5%) survived the ICU stay, and seven (17%) lived to hospital discharge. The most common etiologies of ICU mortality included bacterial pneumonia, cytomegalovirus pneumonia, diffuse alveolar hemorrhage, sepsis, and aspergillosis. The factors associated with higher mortality were older age when performing HSCT, older age at ICU admission, higher acute physiology and chronic health evaluation (APACHE) II score, shock, higher respiratory rate, and higher heart rate at the time of ICU admission. Ten patients underwent SLB which resulted in treatment changes in five of them. Three patients had complications of SLB and one patient died of complications. CONCLUSION The ICU mortality rate of mechanically ventilated HSCT recipients was high. Factors associated with ICU mortality were older age, high APACHE II score, presence of shock, and higher respiratory or heart rate at the time of ICU admission. SLB might provide specific diagnosis in HSCT recipients with unexplained pulmonary infiltrates and aid modification of treatment.

Delayed Suspicion, Treatment and Isolation of Tuberculosis Patients in Pulmonology/ Infectious Diseases and Non-Pulmonology/ Infectious Diseases Wards

Background/Purpose Delayed diagnosis and isolation increases the risk of nosocomial transmission of tuberculosis (TB). To assess the risk of delayed management of TB, we analyzed the risk factors of prolonged delay in isolation of smear-positive TB patients in pulmonology/infectious diseases and other wards in a tertiary teaching hospital. Methods We enrolled smear-positive TB patients aged > 16 years with delayed respiratory isolation following hospitalization. Medical records were reviewed retrospectively. Time intervals between admission, order of sputum acid-fast staining, initiation of anti-tuberculous treatment and isolation were compared between pulmonology/infectious diseases wards (PIWs) and other wards. Risk factors were analyzed in patients with prolonged isolation delay of > 7 days in individual groups. Results Isolation was delayed in 191 (73.7%) of 259 hospitalized smear-positive TB patients. Median suspicion, treatment and isolation delays were 0, 3 and 4 days in PIWs and 1, 5 and 7 days in other wards. For patients admitted to non-PIWs, atypical chest radiographs, symptoms without dyspnea or not being admitted from the emergency department (ED) were risk factors for prolonged isolation delay exceeding 7 days. The only risk factor for delayed isolation in patients admitted to PIWs was age ≥ 70 years. Conclusion Delays in suspicion, treatment and isolation of TB patients were longer in non-PIWs. Clinicians should be alert to those admitted to non-PIWs with atypical chest radiographs, atypical symptoms, or not admitted from the ED.

Procalcitonin and C-reactive protein cannot differentiate bacterial or viral infection in COPD exacerbation requiring emergency department visits

Background Viral and bacterial infections are the most common causes of chronic obstructive pulmonary disease (COPD) exacerbations. Whether serum inflammatory markers can differentiate bacterial from virus infection in patients with COPD exacerbation requiring emergency department (ED) visits remains controversial. Methods Viral culture and polymerase chain reaction (PCR) were used to identify the viruses in the oropharynx of patients with COPD exacerbations. The bacteria were identified by the semiquantitative culture of the expectorated sputum. The peripheral blood white blood cell (WBC) counts, serum C-reactive protein (CRP), procalcitonin (PCT), and clinical symptoms were compared among patients with different types of infections. Results Viruses were isolated from 16 (22.2%) of the 72 patients enrolled. The most commonly identified viruses were parainfluenza type 3, influenza A, and rhinovirus. A total of 30 (41.7%) patients had positive bacterial cultures, with the most commonly found bacteria being Haemophilus influenzae and Haemophilus parainfluenzae. Five patients (6.9%) had both positive sputum cultures and virus identification. The WBC, CRP, and PCT levels of the bacteria-positive and bacteria-negative groups were not statistically different. Multivariate analysis showed that patients with increased sputum volumes during the COPD exacerbations had higher risks of recurrent exacerbations in the 1-year period following the first exacerbation. Conclusion WBC, CRP, or PCT could not differentiate between bacterial and viral infections in patients with COPD exacerbation requiring ED visits. Those with increased sputum during a COPD exacerbation had higher risks for recurrent exacerbations.