Outcomes of Noninvasive Ventilation in Obese Patients With Acute Asthma Exacerbations.

BACKGROUND: The role of noninvasive positive pressure ventilation (NIPPV) in acute asthma exacerbation is controversial. However, the outcome of NIPPV in obese patients with asthma during such exacerbation has not been well studied despite well-established relationship between obesity and asthma. STUDY QUESTION: Does body mass index (BMI) play a role in the outcome of NIPPV during an acute exacerbation and does it predict of the success or failure of NIPPV? STUDY DESIGN: The study was a retrospective analysis by design. The purpose of the study was to assess factors predicting the success or failure of NIPPV. The entire cohort was divided into 2 groups: patients who failed NIPPV and patients who did not. Univariate and multivariate regression analysis was used to predict the variables. Stepwise selection method was used to select variables for final regression model. RESULTS: A total 96 patients were included in the study. Of those, 18 patients (18.9%) failed NIPPV and required endotracheal intubation (group 1). Rest (78.1%) did not fail NIPPV (group 2). Mean age of the study population was 48.8 years and 53% of patients were female. In the univariate analysis, the group that did not fail NIPPV (group 2) had significantly higher number of obese patients (47.9% versus 22.2%; P 0.013). Multivariate analysis showed significant association between BMI categories (BMI of 30 or more) and failure of NIPPV (odds ratio 0.26, 95% confidence interval, 0.08-0.85; P-value 0.017). Forced introduction of smoking status as a risk factor did not change the significance of association. CONCLUSION: Despite the limitations of the study design and the sample size, our analysis showed that patients with high BMI (obese) fared well with NIPPV during acute asthma exacerbation. Because there are controversies on use of NIPPV during asthma exacerbation, larger-scale prospective studies are needed to better understand the role of NIPPV in obese patients with asthma during acute exacerbation.

Profile of Acute Asthma Exacerbation in Drug Users.

The characteristics of patients who use heroin, cocaine, or both and present with acute asthma exacerbations have not been well studied. In this retrospective study, we aimed to study the demographic characteristics of this patient population, the characteristics of their asthma attack, and the risk factors for the need for invasive mechanical ventilation in this patient population. We reviewed the charts of patients discharged from an inner-city hospital with a diagnosis of acute asthma exacerbation. Individuals who used either heroin or cocaine or both within 24 hours of presenting to the emergency department were identified as a cohort of drug users. The rest were classified as non-drug users. Both groups were compared, and a univariate analysis was performed. To assess the predictive value of drug use for the need for intubation in the presence of confounding factors, logistic regression analysis was performed to identify whether using cocaine or heroin or both was an individual predictor for the need for invasive ventilation. Data from 218 patients were analyzed. Drug users (n = 85) were younger (mean age in years 43.9 vs. 50.5, P < 0.01), predominantly male (63.5% vs. 33.8%, P < 0.01), and more likely to be cigarette smokers (90.6% vs. 57.6%, P < 0.01). A medical history of intubation and admissions to the intensive care unit (ICU) was more common among drug users (56.5% vs. 29.3%, P < 0.01 and 54.1% vs. 38.3%, P < 0.03, respectively). Drug use was associated with increased need for invasive mechanical ventilation (35% vs. 23.3%, P = 0.05). Non-drug users were more likely to be using inhaled corticosteroids (48.9% vs. 32.9%, P = 0.03) and had longitudinal care established with a primary care provider (50.6% vs. 68.9%, P < 0.01). After adjusting for a history of mechanical ventilation, history of ICU admission, use of systemic corticosteroids, smoking, and acute physiological assessment and chronic health evaluation 2 score, drug use remained predictive for the need for mechanical ventilation (P = 0.026). Acute asthma exacerbations triggered by cocaine and heroin should be treated aggressively because they represent a cohort with poor follow-up and undertreated asthma as outpatients and are associated with increased need for invasive mechanical ventilation and ICU admission during acute exacerbation.

Near Fatal Asthma in an Inner City Population.

Near-fatal asthma (NFA) is highly prevalent in inner city population. Patients who present with NFA require timely intervention, which necessitates knowledge of appropriate associated risk factors. The purpose of the study was to look and identify the salient features of an asthma exacerbation that are more likely to be associated with NFA in inner city population. We conducted a retrospective analysis of patients who were discharged from the hospital with a diagnosis of acute asthma exacerbation. Two hundred eighteen patients were included in the study. Patients who required intubation during the course of their hospitalization were defined as NFA and the rest were defined as non-near-fatal asthma (NNFA). Multiple patient parameters were compared between the 2 groups; 60 patients met the definition of NFA. There was no difference between NFA and NNFA groups with respect to sex, race, and history of smoking and asthma treatment modalities before presentation. NFA was seen more commonly in heroin (40% vs. 25.9%; P < 0.05) and cocaine users (28.3% vs. 16.5%; P < 0.05). A history of exacerbation requiring intensive care unit (ICU) care was more common among the NFA patients (55% vs. 40.5%; P = 0.05). A history of intubation for an exacerbation was more commonly seen in patients presenting with NFA (51.7% vs. 35.4%; P < 0.05). The NNFA group was more likely to have a primary care physician and to be discharged home (65.6% vs. 51.7%, P < 0.05; and 71.7 vs. 79.1%, P < 0.05). In a multi-logistic regression model, including age, sex, race, heroin and cocaine use, history of intubation and ICU admission, medications, use of noninvasive ventilation, primary care physician, and pH <7.35, PCO2 >45 mm Hg, and FiO2 >40% on initial blood gas, NFA was predicted only by PaCO2 >45 [odds ratio (OR = 6.7; P < 0.001)] and FiO2 >40% (OR = 3.5; P = 0.002). Use of noninvasive ventilation was a negative predictor of NFA (OR = 0.2; P < 0.001). Asthmatic patients who carry a history of intubation with mechanical ventilation for an asthma exacerbation, admissions to the ICU, or those who indulge in recreational drugs like cocaine or heroin should be closely monitored for clinical deterioration.

R-134a (1,1,1,2-Tetrafluoroethane) Inhalation Induced Reactive Airways Dysfunction Syndrome.

R-134a (1,1,1,2-tetrafluoroethane) is widely used as a refrigerant and as an aerosol propellant. Inhalation of R-134a can lead to asphyxia, transient confusion, and cardiac arrhythmias. We report a case of reactive airways dysfunction syndrome secondary to R-134a inhalation. A 60-year-old nonsmoking man without a history of lung disease was exposed to an air conditioner refrigerant spill while performing repairs beneath a school bus. Afterward, he experienced worsening shortness of breath with minimal exertion, a productive cough, and wheezing. He was also hypoxic. He was admitted to the hospital for further evaluation. Spirometry showed airflow obstruction with an FEV1 1.97 L (45% predicted). His respiratory status improved with bronchodilators and oral steroids. A repeat spirometry 2 weeks later showed improvement with an FEV1 2.5 L (60% predicted). Six months after the incident, his symptoms had improved, but he was still having shortness of breath on exertion and occasional cough.

Use of noninvasive ventilation in adult patients with acute asthma exacerbation.

Noninvasive ventilation (NIV) has been found to be beneficial for respiratory failure in many disease states; however, limited data are available supporting its use in acute asthma exacerbation. A retrospective chart analysis of adult patients admitted for acute asthma exacerbation and treated with NIV between January 2007 and December 2009 at a tertiary care community hospital was done. Ninety-eight patient encounters were identified. Mean age of the patients was 48.3 years, and 46% were male. Nineteen patients failed NIV and required invasive ventilation. There was no significant difference in the mean age, sex, race, and initial blood gas between patients with successful versus failed NIV. Usage of drugs, smoking, and history of past hospital or intensive care unit admission or intubation did not significantly influence the rate of failure of NIV. Patients who needed higher initial FiO2 were more likely to get intubated during their hospital stay (46.2 vs. 20.4%, P = 0.019). Patients who failed NIV were found to have longer duration of hospital stay (6.8 vs. 3.9 days, P= 0.016) and longer intensive care unit stay (4 vs. 0.9 days, P = 0.002). Use of inhalers and other medications was not found to significantly influence the rate of failure of NIV. NIV can be used initially in patients with acute asthma exacerbation, as it is associated with shorter duration of hospital stay and can prevent the morbidity of mechanical intubation. Patients with initial requirement of higher FiO2 were more likely to fail NIV and should be carefully monitored.

Multifocal Pulmonary Granular Cell Tumor Presenting with Postobstructive Pneumonia.

Granular cell tumor (GCT) is a neoplasm of Schwann cell origin. Its presence in the aerodigestive tract is uncommon and becomes a diagnostic challenge on initial presentation. Our case is of a 59-year-old woman who presented to the emergency department with a history of productive cough and dyspnea associated with fever and chest pain. An initial chest X-ray (CXR) showed a right middle lobe consolidation with follow-up Computed Tomography (CT) scan showing a mass in the right bronchus. Bronchoscopy revealed a polypoid, sessile granular mass in the right bronchus intermedius with multiple white lesions in trachea, left main bronchus, and right upper bronchi. Histology revealed a benign GCT. Bronchoalveolar lavage from the right middle lobe grew Streptococcus pneumoniae. Patient was treated with intravenous levofloxacin during hospital stay and discharged on a 7-day course of oral antibiotics to be followed as outpatient but was lost to follow-up. GCT can present as a polypoid tumor causing recurrent postobstructive pneumonia. Surgical resection is the most successful treatment option. The tumor is more common in third and fourth decade of life and our patient is the oldest patient, according to our knowledge, to have a GCT.

STOP-BANG questionnaire as a screening tool for diagnosis of obstructive sleep apnea by unattended portable monitoring sleep study.

The Snoring, Tiredness, Observed apnea, high blood Pressure (STOP)-Body mass index (BMI), Age, Neck circumference, and Gender (BANG) questionnaire is a well validated screening tool for diagnosis of Obstructive sleep apnea (OSA) by an in- lab sleep study. However, performance of STOP-BANG as a screening tool for diagnosis of OSA in patients undergoing portable monitoring (PM) sleep study has not been well validated. We conducted a retrospective chart review of patients older than 18 years who had unattended portable monitoring sleep study done at a VA medical center between June 2012 and October 2014. STOP-BANG questionnaire and Epworth sleepiness scale (ESS) were routinely done prior to study. Sensitivity, specificity, and positive predictive value (PPV) various STOP-BANG score thresholds were calculated for diagnosis of OSA defined by Apnea Hypopnea Index (AHI) ≥5. Out of 502 unattended portable monitoring sleep studies, there were 465 males and 37 females. STOP-BANG thresholds of ≥2 and 3 have high sensitivity of 99.8 and 98.9 %, respectively, but very low specificity. Higher score thresholds of ≥7 and 8 have high specificity of 95 and 98.3 %, and PPV of 98.1 and 98.5 %, respectively, but very low sensitivity. A threshold of ≥7 in patients with BMI ≥30 was 100 % specific. The false negative rate for unattended portable monitoring sleep study compared to in-lab study was 80 %. STOP-BANG score thresholds of ≥7 and 8 are highly specific and have high PPV and therefore can potentially reduce need of diagnostic sleep studies in selected patients. Score thresholds of ≤2 or 3 are highly sensitive for AHI ≥5 by unattended portable monitoring sleep study but have high false negative rates. Therefore, in-lab sleep study should be performed to rule out OSA.

A Case of Lung Cancer Originating from Cavitary Mycobacterium xenopi Infection.

Coexistence of Mycobacterium xenopi with lung cancer has been reported. However, lung cancer originating within a pre-existing cavity caused by M. xenopi has not. A 55-y-old woman with a history of smoking presented with complaints of chronic dry cough, night sweats, and weight loss for several months. Computed tomography (CT) scanning revealed a 3.5-cm irregular thick-walled cavity in the right lung apex. Cultures obtained from a CT-guided biopsy grew M. xenopi. The patient received standard treatment, and her clinical symptoms improved, and the radiographic lesion stabilized. However, 2 y later, a repeat chest x-ray showed the original right upper lobe cavity with an interval development of a mass adjoining the cavity. A CT-guided needle biopsy of the new mass demonstrated squamous cell carcinoma. Whenever there is a change in the radiological appearance of a cavity, a repeat biopsy should be performed to exclude lung cancer.