Medical image of the week: a positive methacholine challenge

A methacholine challenge test is one of the methods to assess bronchial hyperresponsiveness (BHR). BHR is one of the features that can contribute to the diagnosis of asthma. The test is reported as a PC-20 value; the inhaled provocative concentration causing a 20% drop or more in the pretest FEV1. This patient had a PC-20 of <0.1 mg/mL which is interpreted as a moderate to severe bronchial hyperresponsiveness by ATS guidelines (1). A normal bronchial response is a PC-20 > 16 mg/ml, 4-16 mg/mL is considered borderline and 1-4 mg/mL is mild BHR according to the ATS guidelines

Medical image of the week: pneumomediastinum

No abstract available. Article truncated at 150 words. A 65 year old man presented with mild increase in shortness of breath. He had a past medical history of diabetes mellitus, hypertension, and severe malnutrition with percutaneous endoscopic gastrostomy (PEG) placement after a colectomy and end ileostomy for sigmoid volvulus. CXR (Figure 1) suggested a pneumomediastinum with subsequent chest CT (Figure 2) confirming moderate sized pneumomediastinum. He had a chronic cough from chronic obstructive pulmonary disease (COPD) as well as aspiration and chest CT also demonstrated emphysema with small blebs. He denied any significant chest pain. He was followed conservatively with imaging and discharged in stable condition. Pneumomediastinum can be caused by trauma, esophageal rupture after vomiting (Boerhaave’s syndrome) and can be a spontaneous event if no obvious precipitating cause is identified (1). Valsalva maneuvers such as cough, sneeze, vomiting and childbirth, can all cause pneumomediastinum. Risk factors include asthma, COPD, interstitial lung disease and inhalational recreational drug use.

Diagnostic workup, etiologies and management of acute right ventricle failure: A state-of-the-art paper

INTRODUCTION: This is a state-of-the-art article of the diagnostic process, etiologies and management of acute right ventricular (RV) failure in critically ill patients. It is based on a large review of previously published articles in the field, as well as the expertise of the authors. RESULTS: The authors propose the ten key points and directions for future research in the field. RV failure (RVF) is frequent in the ICU, magnified by the frequent need for positive pressure ventilation. While no universal definition of RVF is accepted, we propose that RVF may be defined as a state in which the right ventricle is unable to meet the demands for blood flow without excessive use of the Frank-Starling mechanism (i.e. increase in stroke volume associated with increased preload). Both echocardiography and hemodynamic monitoring play a central role in the evaluation of RVF in the ICU. Management of RVF includes treatment of the causes, respiratory optimization and hemodynamic support. The administration of fluids is potentially deleterious and unlikely to lead to improvement in cardiac output in the majority of cases. Vasopressors are needed in the setting of shock to restore the systemic pressure and avoid RV ischemia; inotropic drug or inodilator therapies may also be needed. In the most severe cases, recent mechanical circulatory support devices are proposed to unload the RV and improve organ perfusion CONCLUSION: RV function evaluation is key in the critically-ill patients for hemodynamic management, as fluid optimization, vasopressor strategy and respiratory support. RV failure may be diagnosed by the association of different devices and parameters, while echocardiography is crucial