Long-term tolerance of a fractured self-expanding metal stent in a patient with adenoid cystic carcinoma.

Self-expanding metals stent are used for recanalization of malignant CAO. Fracture of such a stent has been described. This prompts its removal. However removal of a metal stent is difficult and can be hazardous. Due to this US FDA advisory was released against their insertion in benign diseases where long life expectancy can expose the patients to the complications of prolonged indwelling time of these stents. We describe a case of adenoid cystic carcinoma who required SEMS placement for tracheal obstruction. However, stent fracture developed soon after its insertion causing patient to cough out stent pieces multiple times. In view of the challenge associated with removal of metal stent fixed to the tracheal walls at its proximal and distal ends, the stent was left in-situ. Patient has tolerated the fractured stent for 1-year and remains on follow-up without any complication or adverse event. This illustrates the long-term tolerance and safety of a fractured stent and helps to allay anxiety associated with this complication.

Outcome differences between recanalized malignant central airway obstruction from endoluminal disease versus extrinsic compression.

We compared the outcome of Nd:YAG laser therapy with stent placement for malignant central airway obstruction (CAO) at our center over a 10-year period. This is a retrospective review of patients undergoing Nd:YAG laser therapy or self-expanding metal stent (SEMS) placement for malignant CAO between November 2007 and October 2017. Seventy-two patients were recanalized for malignant CAO. The median (range) age was 63 (23-86) years, with 49 (68%) males. Patients underwent either laser therapy alone (N = 36), stent placement alone (N = 30), or both (N = 6). The wavelength of Nd:YAG laser used was 1064 nm, and median (range) laser energy used was 25 (15-35) W, in 377 (115-1107) pulses. Fifty-one (71%) patients died with median survival of 7.2 months. In subgroup analysis, 21 (58.3%) vs. 25 (83.3%), p = 0.03 patients died in the "laser resection" vs. "stent placement" group with longer median survival of 12.4 months in the former vs. 4.5 months, p = 0.0004 in the later. Esophageal cancer and left main bronchus involvement were significantly more common (10 (33.3%) vs. 0, p = 0.0001, and 16 (53.3%) vs. 8 (22.2%), p = 0.01), in the stent placement vs. laser resection group, respectively. Trachea or main bronchi involvement and respiratory failure on presentation requiring mechanical ventilation correlated with poorer survival. The immediate restoration of luminal patency, complication rate, and 30-day mortality was similar among the two groups. The median (range) energy used for laser therapy was 25 (15-35) W. Median of 377 pulses was used for the duration of 287.5 s. The results were compared using a Wilcoxon two-sample test, and Fischer exact test with p values considered indicative of a significant difference if less than 0.05. In patients requiring recanalization of malignant CAO, the extrinsic compression from esophageal cancer, trachea or main bronchi involvement, respiratory failure on presentation requiring mechanical ventilation, and stent placement correlated with poorer survival. Interventional pulmonology training program should emphasize on dedicated training in laser therapy as it is associated with improved survival.

Profiling non-tuberculous mycobacteria in an Asian setting: characteristics and clinical outcomes of hospitalized patients in Singapore.

BACKGROUND: Non-tuberculous mycobacteria (NTM) infection is an increasing problem worldwide. The epidemiology of NTM in most Asian countries is unknown. This study investigated the epidemiology, and clinical profile of inpatients in whom NTM was isolated from various anatomical sites in a Singaporean population attending a major tertiary referral centre. METHODS: Demographic profile, clinical data, and characteristics of patients hospitalized with NTM isolates at a major tertiary hospital over two-year period were prospectively assessed (2011-2012). Data collected included patient demographics, ethnicity, smoking status, co-morbidities, NTM species, intensive care unit (ICU) treatment, and mortality. RESULTS: A total of 485 patients (62.1% male) with 560 hospital admissions were analysed. The median patient age was 70 years. Thirteen different NTM species were isolated from this cohort. Mycobacterium abscessus (M. abscessus) (38.4%) was most frequently isolated followed by Mycobacterium fortuitum (M. fortuitum) (16.6%), Mycobacterium avium complex (MAC) (16.3%), Mycobacterium kansasii (M. kansasii) (15.4%), and Mycobacterium gordonae (M. gordonae) (6.8%). Most (91%) NTM was isolated from the respiratory tract. The three most common non-pulmonary sites were; blood (2.7%), skin wounds and abscesses (2.1%), and gastric aspirates (1.1%). A third (34.4%) of the study population had prior pulmonary tuberculosis (PTB). There was a significant association between isolated NTM species, and patient age (p = 0.0002). Eleven (2.2%) patients received intensive care unit (ICU) treatment during the study period and all cause mortality within 1 year of the study was 16.9% (n = 82). Of these, 72 (87.8%) patients died of pulmonary causes. CONCLUSIONS: The profile of NTM species in Singapore is unique. M. abscessus is the commonest NTM isolated, with a higher prevalence in males, and in the elderly. High NTM prevalence is associated with high rates of prior PTB in our cohort.

Outcome of advanced lung cancer with central airway obstruction versus without central airway obstruction.

Patients with central airway obstruction (CAO) from advanced lung cancer present with significant morbidity and are assumed to have lower survival. Hence, they are offered only palliative support. We asked if patients who have advanced lung cancer with CAO (recanalised and treated) will behave similarly to those with advanced lung cancer without CAO. This study was a retrospective review of the medical records of the patients managed for advanced lung cancer during 2010 and 2015 at our institution. 85 patients were studied. Median survival and 1-, 2- and 5-year survival were 5.8 months, 30.3%, 11.7% and 2.3% versus 9.3 months, 35.7%, 9.6% and 4.7%, respectively, in the CAO and no CAO groups (p=0.30). More patients presented with respiratory failure (15 (35%) versus none; p=0.0001) and required assisted mechanical ventilation (10 (23.3%) versus none; p=0.001) in the CAO group compared with the no CAO group. Fewer patients received chemotherapy in the CAO group (11 (25.5%)) compared with the no CAO group (23 (54.7%); p=0.008). There was no difference in survival among patients with advanced lung cancer whether they presented with CAO or without CAO. Survival was similar to those without CAO in patients with recanalised CAO despite greater morbidity and lesser use of chemotherapy, strongly advocating bronchoscopic recanalisation of CAO. These findings dispel the nihilism associated with such cases.

Ministry of Health Clinical Practice Guidelines: Chronic Obstructive Pulmonary Disease.

The Ministry of Health (MOH) has updated the Clinical Practice Guidelines on Chronic Obstructive Pulmonary Disease (COPD) to provide doctors and patients in Singapore with evidence-based treatment for COPD. This article reproduces the introduction and executive summary (with recommendations from the guidelines) from the MOH Clinical Practice Guidelines on COPD, for the information of SMJ readers. Chapters and page numbers mentioned in the reproduced extract refer to the full text of the guidelines, which are available from the Ministry of Health website: https://www.moh.gov.sg/content/moh_web/healthprofessionalsportal/doctors/guidelines/cpg_medical.html. The recommendations should be used with reference to the full text of the guidelines. Following this article are multiple choice questions based on the full text of the guidelines.

Reversible platypnoea-orthodeoxia syndrome in post-tuberculosis bronchial stenosis.

Bronchial stenosis is known to complicate endobronchial tuberculosis despite medical therapy. It is often associated with dyspnoea. In severe cases, bronchial stenosis results in airflow obstruction, impaired secretion clearance, and can lead to respiratory failure. We present an unusual observation of platypnoea-orthodeoxia syndrome in a young woman with acute atelectasis due to post-tuberculosis bronchial stricture. Imaging revealed complete middle and right lower lobe atelectasis with a partially aerated right upper lobe. In the sitting posture, there was positional worsening of dyspnoea associated with an increase in the alveolar-arterial oxygen gradient and shunt fraction. The likely mechanism was due to gravitational difference in ventilation-perfusion matching. The platypnoea-orthodeoxia syndrome was reversible following balloon dilatation of the bronchial stenosis and expansion of the collapsed lung.

Our Clinical Experience of Self-Expanding Metal Stent for Malignant Central Airway Obstruction.

BACKGROUND: We studied the safety, effectiveness, and limitations of airway stenting using self-expanding metal stent (SEMS) in patients with malignant central airway obstruction (CAO). METHODS: A retrospective review of records of patients undergoing SEMS placement for malignant CAO during year 2013 - 2014 was done. RESULTS: Sixteen patients (11 males and five females) underwent SEMS placement for malignant CAO. Median (range) age was 66 (54 - 78) years. No perioperative or immediate postoperative complications were seen except acute myocardial infarction (AMI) in one patient. Three patients were transferred to intensive care unit (ICU) for closer monitoring after the procedure and were discharged the next day. All four patients with lung atelectasis on presentation experienced complete re-expansion of the lung post-stenting. The dyspnea was substantially relieved in 14 (87.5%) patients. Two of the three patients who had been intubated were weaned off from the ventilator following stent insertion. Stent patency was maintained until death in all patients except one. Median survival from the date of diagnosis and the date of stent placement in lung cancer, esophageal cancer, and thyroid cancer were 140 (21 - 564) and 85 (15 - 361), 288 (80 - 419) and 61 (60 - 171), and 129 (71 - 187) and 67 (16 - 118) days, respectively. This survival was similar to reported expected survival associated with the underlying malignancy. During follow-up, granulation tissue (n = 1), mucostasis (n = 1), and tumor ingrowth (n = 2) were the most frequently encountered complications. CONCLUSION: SEMSs are safe and effective in reversing respiratory failure caused by malignant CAO, averting premature death, allowing application of cancer targeted therapy, and restoring impending shortened survival to expected life expectancy associated with the underlying malignancy.

Significance of coexistent granulomatous inflammation and lung cancer.

AIMS: Coexistence of lung cancer and granulomatous inflammation in the same patient confuses clinicians. We aimed to document the prevalence, clinicopathological features, treatment outcomes and prognosis in patients with coexisting granulomatous inflammation undergoing curative lung resection for lung cancer, in a tuberculosis (TB)-endemic country. METHODS: An observational cohort study of patients with lung cancer undergoing curative resection between 2012 and 2015 in a tertiary centre in Singapore. RESULTS: One hundred and twenty-seven patients underwent lung resection for cancer, out of which 19 (14.9%) had coexistent granulomatous inflammation in the resected specimen. Median age was 68 years and 58.2% were males. Overall median (range) survival was 451 (22-2452) days. Eighteen (14%) patients died at median duration of 271 days after surgery. The postsurgery median survival for those alive was 494 (29-2452) days in the whole group. Subgroup analysis did not reveal any differences in age, gender, location of cancer, radiological features, type of cancer, chemotherapy, history of TB or survival in patients with or without coexistent granulomatous inflammation. CONCLUSIONS: Incidental detection of granulomatous inflammation in patients undergoing lung resection for cancer, even in a TB-endemic country, may not require any intervention. Such findings may be due to either mycobacterial infection in the past or 'sarcoid reaction' to cancer. Although all patients should have their resected specimen sent for acid-fast bacilli culture and followed up until the culture results are reported, the initiation of the management of such patients as per existing lung cancer management guidelines does not affect their outcome adversely.

Diagnostic performance of convex probe EBUS-TBNA in patients with mediastinal and coexistent endobronchial or peripheral lesions.

To compare the performance of convex probe endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA) with conventional endobronchial biopsy (EBB) or transbronchial lung biopsy (TBLB) in patients with mediastinal, and coexisting endobronchial or peripheral lesions.Retrospective review of records of patients undergoing diagnostic EBUS-TBNA and conventional bronchoscopy in 2014.A total of 74 patients had mediastinal, and coexisting endobronchial or peripheral lesions. The detection rate of EBUS-TBNA for mediastinal lesion >1 cm in short axis, EBB for visible exophytic type of endobronchial lesion, and TBLB for peripheral lesion with bronchus sign were 71%, 75%, and 86%, respectively. In contrast, the detection rate of EBUS-TBNA for mediastinal lesion ≤1 cm in short axis, EBB for mucosal hyperemia type of endobronchial lesion, and TBLB for peripheral lesion without bronchus sign were 25%, 63%, and 38%, and improved to 63%, 88%, and 62% respectively by adding EBB or TBLB to EBUS-TBNA, and EBUS-TBNA to EBB or TBLB. Postprocedure bleeding was significantly more common in patients undergoing EBB and TBLB 8 (40%) versus convex probe EBUS-TBNA 2 patients (2.7%, P = 0.0004).EBUS-TBNA is a safer single diagnostic technique compared with EBB or TBLB in patients with mediastinal lesion of >1 cm in size, and coexisting exophytic type of endobronchial lesion, or peripheral lesion with bronchus sign. However, it requires combining with EBB or TBLB and vice versa to optimize yield when mediastinal lesion is ≤1 cm in size, and coexisting endobronchial and peripheral lesions lack exophytic nature, and bronchus sign, respectively.

Pleural LDH as a prognostic marker in adenocarcinoma lung with malignant pleural effusion.

To study the performance of serum and pleural lactate dehydrogenase (LDH) level in predicting survival in patients with adenocarcinoma lung presenting with malignant pleural effusions (MPE) at initial diagnosis.Retrospective cohort study of the patient hospitalized for adenocarcinoma lung with MPE in year 2012.Univariate analyses showed lower pleural fluid LDH 667 (313-967) versus 971 (214-3800), P = 0.04, female gender 9 (100%) versus 27 (41.5%), P = 0.009, never smoking status 9 (100%) versus 36 (55.3%), P = 0.009, and epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) therapy 8 (89%) versus 26 (40%), P = 0.009 to correlate with survival of more than 1.7 year versus less than 1.7 year. In multivariate analysis, low pleural fluid LDH and female gender maintained significance. The pleural LDH level of ≤1500 and >1500 U/L discriminated significantly (P = 0.009) between survival.High pleural LDH (>1500 IU/L) predicts shorter survival (less than a year) in patients with adenocarcinoma lung presenting with MPE at the time of initial diagnosis. This marker may be clinically applied for selecting therapeutic modality directed at prevention of reaccumulation of MPE. Patients with low pleural LDH may be considered suitable for measures that provide more sustained effect on prevention of reaccumulation such as chemical pleurodesis or tunneled pleural catheter.

Evaluation of pulmonary nodules in Asian population.

BACKGROUND: American College of Chest Physicians (ACCP) provides guidelines to manage pulmonary nodules. Pulmonary nodules however can be malignant or benign. Similar incidence of tuberculosis (TB) and lung cancer in Asian countries raises concern over the relevance of suggested guidelines in Asian population. There is little data on the pattern of clinical practice in the management of pulmonary nodules in Asian country (Singapore). Our study describes the current pattern of clinical practice in this area highlighting the variation in practice and discussing the potential reasons. METHODS: Retrospective review of the medical records of patients diagnosed with lung cancer in 2010. RESULTS: Sixty nodules were identified in 32 patients. Nodules were detected incidentally on routine imaging in 7 (21.9%) patients. TB contact tracing and pre-employment screening were common ways by which nodules were detected incidentally. Over one third (37.5%) were non-smokers. Majority of nodules were located in the upper lobes of right and left lung followed by right lower lobe (RLL). Only few patients 8 (25%) had positron emission tomography (PET) scan for staging purposes. There were no difference in survival between patients who presented with single, 747 (range, 25-1,840) days vs. multiple nodules 928 (range, 30-2,572) days, P=0.26. In a retrospective analysis of malignancy risk with the probability calculator, 62.5% patients were at low-moderate risk whilst 32.5% were at high risk. CONCLUSIONS: The clinical practice of managing pulmonary nodules in Asian population differs from ACCP guidelines. None of the patient had pre-test probability calculated, and few had PET scan. This is because upper lobe predominance of lung cancer is identical to TB, non-smoking history does not have any weight in discounting malignancy risk where many of the Asian lung cancer patients are non-smokers, and the local endemicity of TB and its confounding effect on radiological findings of CT scan and PET scan.

Role of Bronchoscopy in Prompt Discharge From the Intensive Care Unit.

BACKGROUND: Intensive care unit (ICU) stays are 2.5 times more costly than other hospital stays, and 93.3% of ICU use is for respiratory disease with ventilator support. The aim of this study was to assess the role of bronchoscopy on discontinuation of mechanical ventilation, and prompt discharge from ICU in our institution. METHODS: Retrospective review of medical records of patients referred for bronchoscopic intervention for acute respiratory failure from malignant or benign central airway diseases requiring ICU admission. RESULTS: Twelve critically ill patients were studied. Median (range) age was 63 years (range, 35 to 85 y). Nine (75%) had endotracheal tube, and 3 (25%) had tracheostomy tube. Nine (75%) of 12 patients admitted to ICU could be transferred to general ward after median (range) interval of 2 days (range, 1 to 7 d) after the day of intervention. Median (range) prebronchoscopy and postbronchoscopy PaO2/FiO2 ratio was 102.8 (range, 99.2 to 328) and 180 (range, 129 to 380), respectively, with significant improvement postintervention (P=0.002). Radiologically, all 8 patients with lung atelectasis on presentation experienced complete reexpansion of the lung on the day after bronchoscopic intervention. CONCLUSION: The majority of patients in our cohort (75%) of benign and malignant etiology could be promptly (within 2 d postbronchoscopy) transferred out from ICU to general ward after successful discontinuation of mechanical ventilation and extubation after bronchoscopic intervention. We advocate early recognition and bronchoscopic intervention in suitable patients.

Timeliness of Diagnosing Lung Cancer: Number of Procedures and Time Needed to Establish Diagnosis: Being Right the First Time.

To study number of procedures and time to diagnose lung cancer and factors affecting the timeliness of clinching this diagnosis. Retrospective cohort study of lung cancer patients who consecutively underwent diagnostic bronchoscopy in 1 year (October 2013 to September 2014). Out of 101 patients diagnosed with lung cancer from bronchoscopy, average time interval between first abnormal computed tomogram (CT) scan-to-1st procedure, 1st procedure-to-diagnosis, and 1st abnormal CT scan-to-diagnosis was 16 ± 26, 11 ± 19, and 27 ± 33 days, respectively. These intervals were significantly longer in those requiring repeat procedures. Multivariate analysis revealed inconclusive 1st procedure to be the predictor of prolonged (>30 days) CT scan to diagnosis time (P = 0.04). Twenty-nine patients (28.7%) required repeat procedures (n = 63). Reasons behind repeating the procedures were inadequate procedure (n = 14), inaccessibility of lesion (n = 9), inappropriate procedure (n = 5), mutation analysis (n = 2), and others (n = 2). Fifty had visible endo-bronchial lesion, 20 had positive bronchus sign, and 83 had enlarged mediastinal/hilar lymph-nodes or central masses adjacent to the airways. Fewer procedures, and shorter procedure to diagnosis time, were observed in those undergoing convex probe endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA) (P = 0.04). Most patients exhibit enlarged mediastinal lymph node or mass adjacent to the central airway accessible by convex probe EBUS-TBNA. Hence, combining it with conventional bronchoscopic techniques such as bronchoalveolar lavage, brush, and forceps biopsy increases detection rate, and reduces number of procedures and time to establish diagnosis. This may translate into cost and resource savings, timeliness of diagnosis, greater patient satisfaction, and conceivably better outcomes.

Acute respiratory distress syndrome in critically ill patients with severe acute respiratory syndrome.

CONTEXT: Severe acute respiratory syndrome (SARS) is an emerging infectious disease with a 25% incidence of progression to acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) and mortality exceeding 10%. OBJECTIVE: To describe the clinical spectrum and outcomes of ALI/ARDS in patients with SARS-related critical illness. DESIGN, SETTING, AND PATIENTS: Retrospective case series of adult patients with probable SARS admitted to the intensive care unit (ICU) of a hospital in Singapore between March 6 and June 6, 2003. MAIN OUTCOME MEASURES: The primary outcome measure was 28-day mortality after symptom onset. RESULTS: Of 199 patients hospitalized with SARS, 46 (23%) were admitted to the ICU, including 45 who fulfilled criteria for ALI/ARDS. Mortality at 28 days for the entire cohort was 20 (10.1%) of 199 and for ICU patients was 17 (37%) of 46. Intensive care unit mortality at 13 weeks was 24 (52.2%) of 46. Nineteen of 24 ICU deaths occurred late (> or =7 days after ICU admission) and were attributed to complications related to severe ARDS, multiorgan failure, thromboembolic complications, or septicemic shock. ARDS was characterized by ease of derecruitment of alveoli and paucity of airway secretion, bronchospasm, or dynamic hyperinflation. Lower Acute Physiology and Chronic Health Evaluation II scores and higher baseline ratios of PaO2 to fraction of inspired oxygen were associated with earlier recovery. CONCLUSIONS: Critically ill patients with SARS and ALI/ARDS had characteristic clinical findings, high rates of complications; and high mortality. These findings may provide useful information for optimizing supportive care for SARS-related critical illness.