Pulmonary Function Testing in Patients with Tracheostomies: Feasibility and Technical Considerations

Purpose

Pulmonary function testing (PFT) in patients with tracheostomies has been perceived as difficult to perform and clinically unreliable. We studied the feasibility, quality, repeatability and clinical significance of PFT.

Methods

Patients with tracheostomies that underwent PFT from January 1, 2010 to February 29, 2012 were identified. Clinical history and PFT data were reviewed retrospectively.

Results

Fifty patients (88% men) were identified. Forty-seven (94%) patients were able to perform PFT. Acceptable repeatability was obtained for FVC in 39 (83%) and for FEV1 in 41 (87%). Patients with tracheostomies showed difficulty in meeting ATS end-of-test criteria; only 9 (19%) met plateau criteria and 25 (53%) had exhalation times of greater than 6 s. Obstructive pattern was observed in 30 (64%) and restrictive pattern in 9 (19%). DLCO measurements were attempted in 43 patients and satisfactorily obtained in 34 (79%).

Conclusions

PFT can be performed with reliability in patients with tracheostomies, and they are useful for detecting and classifying types of lung dysfunction.

     

Severe refractory hypoxemia following a gunshot injury

We describe the case of a 57-year-old man with severe refractory hypoxemia, despite receiving ventilation therapy with 100% oxygen, following a gunshot wound to his left chest. A limited CT scan of the chest with contrast raised the suspicion of an arteriovenous (AV) fistula. Contrast-enhanced transthoracic echocardiography confirmed the presence of a pulmonary AV fistula. Traumatic pulmonary AV fistula is a rare, but serious and life-threatening condition that should be suspected in patients with thoracic injuries with persistent unexplained hypoxemia. Contrast echocardiography is a relatively simple, inexpensive, and readily available bedside test that can be used to confirm this diagnosis.     

Putative roles of a proline–glutamic acid-rich protein (PE3) in intracellular survival and as a candidate for subunit vaccine against Mycobacterium tuberculosis

The proline–glutamic acid (PE) protein family of Mycobacterium tuberculosis (Mtb) plays diverse roles in the pathogenesis and modulation of host immune responses. The uniqueness of conserved regions of PE proteins may be useful to test and validate their corresponding functions. Hence, the present study has been undertaken to demonstrate the role of PE3 (Rv0159c) for persistence, host immune response and immunoprophylaxis. We have expressed Mtb-specific PE3 gene in M. smegmatis (MS) and used the strain to infect J774A.1 macrophage cells and BALB/c mice. It was observed that during the infection, the MS expressing PE3 showed higher bacterial load when compared to infection with wild-type MS. In hypoxic condition, the expression level of PE3 gene was induced in Mtb, which further showed its relevance in the cell survival during hypoxia-induced persistence. The expression level of PE3 in Mtb was markedly induced during chronic stage of murine infection, which reiterated its importance in mycobacterial persistence in the host. The immunization of mice with recombinant PE3 protein stimulated the secretion of TNF, IL-6 and IL-2 cytokines and generated strong protective immunity against challenge with live mycobacteria, which was evidenced by decreased viable bacilli in the lungs, histopathological changes and increased survival of PE3 immunized mice. Conclusively, the results indicated that PE3 plays significant roles in mycobacterial persistence during infection, modulate host immune response and hence could be a prospective candidate for the development of subunit vaccine against tuberculosis.     

Association Between Alcohol Use and HIV-Related Sexual Risk Behaviors Among Men Who Have Sex with Men (MSM): Findings from a Multi-Site Bio-Behavioral Survey in India

This paper examines the association between alcohol use and HIV-related sexual risk behaviors among men who have sex with men (MSM). A cross-sectional bio-behavioral survey was conducted among 3,880 MSM, recruited using time-location cluster sampling from cruising sites in three Indian states. Nearly three-fifths of the participants reported alcohol use. Among frequent users (40 % of the sample), defined as those who consumed alcohol daily or at least once a week, 66 % were aged 25 years and above, 53 % self-identified as kothi (feminine/receptive), and 63 % consistently used condoms with male paying partners. Multivariate logistic regression demonstrated that frequent users were more likely to be aged 25 years and above, less likely to self-identify as kothi, and less likely to consistently use condoms with male paying (AOR = 0.7; 95 % CI 0.5–0.9) and male regular (AOR = 0.7; 95 % CI 0.6–0.9) partners. HIV prevention interventions for MSM need to provide tailored information on alcohol use-related sexual risk, especially for MSM in sex work and MSM with male regular partners.     

Rhabdomyolysis in Bariatric Surgery: a Systematic Review

Background

Rhabdomyolysis (RML) is a rare complication of bariatric surgery. A systematic review was performed to identify risk factors and patient outcomes in morbidly obese patients undergoing bariatric surgery who develop RML.

Methods

A comprehensive search was performed between January 1990 and March 2012 using relevant MeSH terms. Studies were chosen based on predefined inclusion criteria. RML was defined as a creatine kinase of more than 1,000 IU/L. The parameters assessed included patient characteristics of the RML population, type of bariatric surgery performed, operating time, complications, presentation and diagnosis of RML.

Results

Twenty-two studies were analysed which included 11 case reports, two case series, six prospective and three retrospective comparative studies. Overall 145 patients with RML were reported following bariatric surgery. Acute renal failure was found in 20 patients (14 %) and was significantly more likely to occur in patients with postoperative muscle pain (p?<?0.05). The mortality rate after renal failure was 25 % (n?=?5). In the comparative studies, 87 RML patients were compared with 325 non-RML patients. The RML patients were more likely to be male, had a greater mean body mass index (BMI) (52 vs 48 kg/m², p?<?0.01) and underwent a longer operation (255 vs 207 min, p?<?0.01) compared to non-RML patients.

Conclusions

Risk factors of developing RML following bariatric surgery include male gender, elevated BMI and prolonged operating time. Patients with a biochemical diagnosis of RML and postoperative myalgia after bariatric surgery are at increased risk of developing acute renal failure and mortality. These patients must be identified and treated promptly.