Christopher S. King

Idiopathic pulmonary fibrosis: effects and optimal management of comorbidities

Despite the development of pharmacological therapies that are effective in slowing the progression of idiopathic pulmonary fibrosis (IPF), it remains a debilitating and lethal condition. In addition to the adverse effects caused by pulmonary fibrosis, most patients with IPF have associated comorbid conditions, which might negatively affect functional status, quality of life, and survival. Comorbid conditions can be pulmonary or extrapulmonary. Pulmonary comorbidities include pulmonary hypertension, emphysema, and lung cancer, while non-pulmonary conditions include venous thromboembolism, coronary artery disease, congestive heart failure, sleep-disordered breathing, gastro-oesophageal reflux disease, and anxiety or depression. Although some of these comorbid conditions share risk factors with IPF, the likelihood for their presence or development in patients with IPF is still greater than expected. This might indicate that IPF fosters an environment for the development or perpetuation of comorbid conditions, or alternatively that they share causative factors. Optimal management of IPF therefore requires a comprehensive approach, which includes the identification and treatment of comorbid conditions to optimise patient outcomes.

Pulmonary artery size as a predictor of pulmonary hypertension and outcomes in patients with chronic obstructive pulmonary disease

RATIONALE The relationship between pulmonary artery size with underlying pulmonary hypertension and mortality remains to be determined in COPD. We sought to evaluate the relationships in a cohort of patients with advanced COPD. METHODS A retrospective study of advanced COPD patients evaluated between 1998 and 2012 was conducted at a tertiary care center. Patients with chest computed tomography images and right heart catheterizations formed the study cohort. The diameters of the pulmonary artery and ascending aorta were measured by independent observers and compared to pulmonary artery pressures. Intermediate-term mortality was evaluated for the 24-month period subsequent to the respective studies. Cox proportional hazards model was used to determine independent effects of variables on survival. RESULTS There were 65 subjects identified, of whom 38 (58%) had pulmonary hypertension. Patients with and without pulmonary hypertension had mean pulmonary artery diameters of 34.4 mm and 29.1 mm, respectively (p = 0.0003). The mean PA:A ratio for those with and without pulmonary hypertension was 1.05 and 0.87, respectively (p = 0.0003). The PA:A ratio was an independent predictor of mortality with a reduced survival in those with a PA:A >1 (p = 0.008). CONCLUSIONS The PA:A ratio is associated with underlying pulmonary hypertension in patients with COPD and is an independent predictor of mortality. This readily available measurement may be a valuable non-invasive screening tool for underlying pulmonary hypertension in COPD patients and appears to impart important independent prognostic information.

Pulmonary artery size as a predictor of outcomes in idiopathic pulmonary fibrosis.

IPF patients have heightened propensity for pulmonary hypertension, which portends a worse outcome. Presence of pulmonary hypertension may be reflected in an enlarged pulmonary artery. We investigated pulmonary artery size measured on high-resolution computed tomography (HRCT) as an outcome predictor in IPF. We retrospectively reviewed all IPF patients evaluated at a tertiary-care centre between 2008 and 2013. Pulmonary artery and ascending aorta diameters were measured from chest HRCT with pulmonary artery:ascending aorta diameter (PA:A) ratio calculations. Outcome analysis defined by either death or lung transplant based on pulmonary artery size and PA:A ratio over 60 months was performed. Independent effects of different variables on overall outcomes were evaluated using the Cox proportional hazards model. 98 IPF patients with available HRCT scans had a mean pulmonary artery diameter and PA:A ratio of 32.8 mm and 0.94, respectively. Patients with a PA:A ratio >1 had higher risk of death or transplant compared with a PA:A ratio ≤1 (p<0.001). A PA:A ratio >1 was also an independent predictor of outcomes in unadjusted and adjusted outcomes analyses (hazard ratio 3.99, p<0.001 and hazard ratio 3.35, p=0.002, respectively). A PA:A ratio >1 is associated with worse outcomes in patients with IPF. HRCT PA:A ratio measurement may assist in risk stratification and prognostication of IPF patients. Pulmonary artery measurements on imaging can be utilised for risk stratification and prognostication in IPF http://ow.ly/WNO2h

Management of Right Heart Failure in the Critically Ill

Right ventricular failure complicates several commonly encountered conditions in the intensive care unit. Right ventricular dilation and paradoxic movement of the interventricular septum on echocardiography establishes the diagnosis. Right heart catheterization is useful in establishing the specific cause and aids clinicians in management. Principles of treatment focus on reversal of the underlying cause, optimization of right ventricular preload and contractility, and reduction of right ventricular afterload. Mechanical support with right ventricular assist device or veno-arterial extracorporeal membrane oxygenation can be used in select patients who fail to improve with optimal medical therapy.

Cardiac Support: Emphasis on Venoarterial ECMO

Major advances have been made in mechanical circulatory support in recent years. Venoarterial (VA) extracorporeal membrane oxygenation (ECMO) provides both pulmonary and circulatory support for critically ill patients with hemodynamic compromise, serving as a bridge to recovery or definitive therapy in the form of transplant or a durable ventricular assist device. In the past, VA ECMO support was used in cases of cardiogenic shock or failure to wean from cardiopulmonary bypass; however, the technology is now being applied to an ever-expanding list of conditions, including massive pulmonary embolism, cardiac arrest, drug overdose, and hypothermia.

Early postoperative management after lung transplantation: Results of an international survey

Little data exist regarding optimal therapeutic strategies postoperatively after lung transplant (LTx). Current practice patterns rely on expert opinion and institutional experience resulting in nonuniform postoperative care. To better define current practice patterns, an international survey of LTx clinicians was conducted.

Exercise pulmonary haemodynamic response predicts outcomes in fibrotic lung disease

Pulmonary hypertension is diagnosed by an elevated mean pulmonary arterial pressure (mPAP) during resting right heart catheterisation (RHC) [1]. Although “exercise-induced pulmonary hypertension” is no longer a distinct clinical entity, recently, there has been renewed interest in the prognostic value of pulmonary haemodynamic responses to exercise, particularly in patients with fibrotic lung disease [1–4]. As the optimal use of exercise RHC in this cohort remains unknown, our main objective in this study was to study the relationship between exercise haemodynamics and outcomes in fibrotic lung disease patients [3–7]. Haemodynamic changes with exercise, including ΔmPAP/ΔCO, predict clinical worsening in fibrotic lung disease patients http://ow.ly/uKno30lb5fF

Prevalence and Impact of WHO Group 3 Pulmonary Hypertension in Advanced Idiopathic Nonspecific Interstitial Pneumonia

Pulmonary hypertension (PH) is associated with impaired quality of life, worsened functional status and increased mortality in idiopathic pulmonary fibrosis (IPF) [1]. The prevalence and clinical impact in other idiopathic interstitial pneumonias (IIPs) has not previously been reported. Given the prognostic significance of PH in IPF, we sought to determine the prevalence and severity of World Health Organization (WHO) group 3 PH in a cohort of patients with biopsy-proven idiopathic nonspecific interstitial pneumonia (NSIP). We recognised that the prevalence of PH in this population of patients with advanced NSIP would be an overestimation of the NSIP population at large, but felt that mandating surgical lung biopsy and right heart catheterisation (RHC) were the only way to ensure accurate diagnosis of NSIP and PH, respectively. Group 3 pulmonary hypertension commonly complicates idiopathic NSIP and is associated with adverse outcomes http://ow.ly/jsa930jMaSD

Critical Care of the Adult Patient With Cystic Fibrosis

&NA; Cystic fibrosis (CF) is a multiorgan, genetic disease resulting from dysfunction of the CF transmembrane conductance regulator. The primary clinical manifestations are bronchiectasis, chronic pulmonary infections with recurrent exacerbations, and pancreatic insufficiency. Advances in CF care have led to improved survival, with more than one‐half of those affected being adults. As a result, adult pulmonary and critical care physicians increasingly will be involved in the care of these patients. Patients with CF are at risk for numerous conditions that require ICU admission, including respiratory failure, massive hemoptysis, pneumothorax, hepatic failure, and bowel obstruction. Multiple aspects of the care of patients with CF benefit from specialized knowledge, including pancreatic enzyme replacement and nutritional support; airway clearance modalities; treatment of multiply resistant, polymicrobial infections, and unique drug metabolism. In extreme cases, patients may benefit from advanced therapies, including extracorporeal support and organ transplant. Optimal care of patients with CF requires a multidisciplinary care team that includes respiratory therapists, dieticians, social workers, psychologists, pharmacists, and physicians who have expertise in the treatment of this complex, multisystem disorder.

Treatment of Pulmonary Hypertension in Interstitial Lung Disease

The interstitial lung diseases (ILD) are a heterogeneous group of disorders characterized by diffuse pulmonary parenchymal infiltrates. The prognosis of ILD varies among the specific etiologies, but frequently results in substantial morbidity and mortality. For example, idiopathic pulmonary fibrosis (IPF), the commonest form of the idiopathic interstitial pneumonias, has a median survival of only 2.5–5 years [1, 2]. The pharmacologic therapy of ILD varies with the underlying cause, but generally focuses on attenuating inflammation and resultant fibrosis through the use of corticosteroids, alternative immunosuppressant agents, and antifibrotics for IPF. Although frequently prescribed, the data supporting the utility of pharmacologic therapy in ILD is limited. Recent landmark trials of pirfenidone and nintedanib in IPF, while representing a major advance in the treatment of IPF, illustrate this point [3, 4]. The mean change in forced vital capacity (FVC) over 52 weeks was −235 mL for pirfenidone versus −428 mL for placebo while the adjusted annual rate of change with nintedanib was −114.7 mL versus −239.9 mL for placebo [3, 4]. It appears that even with the availability of these agents, the relentless downhill course of IPF will continue, as will the search for further therapeutic targets.