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.

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 (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.

Anemia is a known comorbidity found in chronic obstructive pulmonary disease (COPD) patients. Hypoxemia is common and basically due to ventilation/perfusion (V/Q) mismatch in COPD. Anemia, by decreasing arterial oxygen content, may be a contributing factor for decreased delivery of oxygen to tissues. The objective of this study is to determine if anemia is a factor in qualifying COPD patients for home oxygen therapy. The study was designed as a retrospective, cross-sectional, observational chart review. Patients who were referred for home oxygen therapy evaluation were selected from the computerized patient record system. Demographic data, oxygen saturation at rest and during exercise, pulmonary function test results, hemoglobin level, medications, reason for anemia, comorbid diseases, and smoking status were recorded. The χ tests, independent sample t tests, and logistic regression were used for statistical analysis. Only 356 of total 478 patient referrals had a diagnosis of COPD over a 2-year period. Although 39 of them were excluded, 317 patients were included in the study. The overall rate of anemia was 38% in all COPD patients. Anemia was found significantly more frequent in COPD patients on home oxygen therapy (46%) than those not on home oxygen therapy (18.5%) (P < 0.0001). Mean saturation of peripheral oxygen values were significantly lower in anemic COPD patients both at rest and during exercise (P < 0.0001). Also, in COPD patients, age, Global Initiative for Chronic Obstructive Lung Disease class, smoking status, hemoglobin level, hematocrit, percent of forced expiratory volume in first second, forced expiratory volume in first second/forced vital capacity, residual volume/total lung volume, percent of carbon monoxide diffusion capacity were significantly different between home oxygen therapy and those not on home oxygen therapy (P < 0.05). Multivariate logistic regression showed that anemia remained a strong predictor for long-term oxygen therapy use in COPD patients after adjusting for other significant parameters. Anemic COPD patients are more hypoxic especially during exercise than those who are not anemic. We conclude that anemia is a contributing factor in qualifying COPD patients for home oxygen therapy.