Jason Stamm

Peripherally inserted central venous catheter-associated thrombosis : Retrospective analysis of clinical risk factors in adult patients

Background: Peripherally inserted central catheters (PICC) are common venous access devices. Clinical conditions and therapies that increase the risk of PICC-associated thrombosis have not been studied. Methods: We performed a retrospective case-control analysis of all adult patients who underwent placement of a PICC at our hospital over a three-year period (n = 1296). Clinical variables examined were indication for PICC placement, active cancer treatment, history of DVT, diabetes mellitus, and use of prophylactic anticoagulation. Results: The overall incidence of PICC-associated DVT was 2% (n = 27). Active cancer therapy was significantly associated with PICC-associated DVT (OR 3.5, 95% CI 1.3-9.8). The use of prophylactic anticoagulation did not reduce this risk. Conclusions: Patients who suffered a PICC-associated DVT were more likely to be undergoing treatment for cancer. This risk was not lowered by the use of prophylactic anticoagulation. These results suggest a need for prospective studies on effective anticoagulation for patients at high risk for PICC-associated DVT.

Overview of current therapeutic approaches for pulmonary hypertension.

There have been tremendous strides in the management of pulmonary hypertension over the past 20 years with the introduction of targeted medical therapies and overall improvements in surgical treatment options and general supportive care. Furthermore, recent data shows that the survival of those with pulmonary arterial hypertension is improving. While there has been tremendous progress, much work remains to be done in improving the care of those with secondary forms of pulmonary hypertension, who constitute the majority of patients with this disorder, and in the optimal treatment approach in those with pulmonary arterial hypertension. This article will review general and targeted medical treatment, along with surgical interventions, of those with pulmonary hypertension.

Medical Malpractice: Reform for Today's Patients and Clinicians

The current system of medical malpractice does a poor job of serving the best interests of physicians or patients. Economic and societal forces are shifting the nature of health care from the individual physician to a system of health care professionals, characterized by accountable care organizations. In particular, more physicians are employed, quality and outcomes are routinely measured, and reimbursement is moving to value-based purchasing. Medical malpractice likewise needs to transition to a new model that is consistent with the modern era of patient-centered care. Collective accountability, the concept that patient care is the responsibility of all the members of the health care organization, requires malpractice reform that reflects a systems-based practice of medicine. Enterprise liability, coupled with medical error communication and resolution programs, provides the legal framework necessary for the patient-centered practice of medicine in todays environment.

Risk stratification in acute pulmonary embolism: frequency and impact on treatment decisions and outcomes.

Objectives Guidelines have recommended that risk stratification be performed in patients diagnosed with an acute pulmonary embolism (PE). No study has described the use of risk stratification in routine clinical practice. The purpose of this study was to measure the frequency and impact of risk stratification on treatment decisions and outcomes in patients admitted with acute PE. Methods A retrospective cohort study was conducted of all of the patients admitted with acute PE at two Geisinger community-based teaching hospitals between 2006 and 2011. Baseline demographics, vital signs, and relevant clinical variables were recorded. The Pulmonary Embolism Severity Index was calculated for each patient. Risk stratification was defined as the measurement of either a biomarker or an echocardiogram within 24 hours of admission. The outcomes measured were short-term adverse events (in-hospital mortality or need for intensive care) and 30-day mortality. Results The mean age for the study cohort (n = 889) was 61 ± 17 years and 52% were men. Overall, 59% of study subjects were risk stratified. The frequency of risk stratification did not change over time. Risk stratification was associated with assignment to a higher acuity of care and increased use of thrombolysis and inferior vena cava filter placement. When controlling for severity of illness, risk stratification was a significant predictor of worsened short-term adverse outcome (odds ratio 3.43, 95% confidence interval 1.75–6.74, P < 0.001) but was not associated with improved 30-day mortality (odds ratio 1.14, 95% confidence interval 0.66–1.95, P = 0.64). Conclusions Risk stratification is frequently performed in patients admitted with acute PE and has had a stable prevalence during a 5-year period. The use of risk stratification in acute PE is associated with assignment to higher levels of care and with more advanced treatments. Despite more intense treatment, risk stratification does not improve either short-term outcomes or 30-day mortality.

Elevated N-Terminal Pro-Brain Natriuretic Peptide Is Associated with Mortality in Tobacco Smokers Independent of Airflow Obstruction

Background Tobacco use is associated with an increased prevalence of cardiovascular disease. N-terminal pro-brain natiuretic peptide (NT-proBNP), a widely available biomarker that is associated with cardiovascular outcomes in other conditions, has not been investigated as a predictor of mortality in tobacco smokers. We hypothesized that NT-proBNP would be an independent prognostic marker in a cohort of well-characterized tobacco smokers without known cardiovascular disease. Methods Clinical data from 796 subjects enrolled in two prospective tobacco exposed cohorts was assessed to determine factors associated with elevated NT-proBNP and the relationship of these factors and NT-proBNP with mortality. Results Subjects were followed for a median of 562 (IQR 252 – 826) days. Characteristics associated with a NT-proBNP above the median (≥49 pg/mL) were increased age, female gender, and decreased body mass index. By time-to-event analysis, an NT-proBNP above the median (≥49 pg/mL) was a significant predictor of mortality (log rank p = 0.02). By proportional hazard analysis controlling for age, gender, cohort, and severity of airflow obstruction, an elevated NT-proBNP level (≥49 pg/mL) remained an independent predictor of mortality (HR = 2.19, 95% CI 1.07–4.46, p = 0.031). Conclusions Elevated NT-proBNP is an independent predictor of mortality in tobacco smokers without known cardiovascular disease, conferring a 2.2 fold increased risk of death. Future studies should assess the ability of this biomarker to guide further diagnostic testing and to direct specific cardiovascular risk reduction inventions that may positively impact quality of life and survival.

Too Much of a Good Thing: Appropriate CTPA Use in the Diagnosis of PE

There is abundant evidence that the use of computed tomography pulmonary angiography (CTPA) is increasing in emergency departments and more patients are being diagnosed with pulmonary embolism (PE).1,2 The increasing availability and resolution of CTPA technology since the late 1990s has led some to suggest that PE is now being overdiagnosed, which is supported by decreasing PE case–fatality rates and the detection of small, subsegmental clots that do not result in any meaningful right-ventricular dysfunction.3,4 Indeed, recent guidelines allow that not all small PEs require anticoagulation therapy.5 Beyond overdiagnosis, there are potential patient-level harms associated with the liberal use of CTPA imaging, including the consequences of radiation and intravenous contrast exposure.4,6 At the societal level, excess CTPA use contributes to the growing costs of healthcare.2,7 Despite the above concerns, CTPA remains the diagnostic test of choice for PE. There are multiple approaches that are suggested to appropriately use CTPA in the workup of suspected PE, the most common of which is endorsed by best practice publications and combines a clinical score (eg, Well’s score) with D-dimer testing, reserving CTPA for those patients with high clinical risk and/or positive D-dimer.8,9 Despite the professional recommendation, studies have shown that the use of PE diagnostic algorithms in clinical practice is suboptimal, resulting in much practice variation and contributing to the overuse of CTPA.10,11 In this issue, as a means of clarifying what measures improve adherence with recommended best practices, Deblois and colleagues12 perform a systematic review of the published interventions that have attempted to reduce CTPA imaging in the diagnosis of PE. Deblois and colleagues are to be commended for summarizing what is unfortunately a very heterogeneous literature, the limitations of which precluded a formal meta-analysis. The authors report that most of the 17 reviewed studies incorporated either electronic clinical decision support (CDS; usually imbedded into a computerized physician order entry) tools or educational interventions in a retrospective, before-and-after design; only 3 studies were experimental and included a control group. Most of the studies included effi cacy, with a few evaluating safety. There was little available evidence regarding cost-effectiveness or barriers to implementation. The most studied approach, CDS, was associated with a decrease in the use of CTPA of between 8.3% and 25.4% along with an increase in PE diagnostic yield of between 3.3% and 4.4%. Likewise, the appropriate use of CTPA (consistent with best practice recommendations) increased with CDS intervention f rom 18% to 19%. The addition of individual performance feedback seemed to enhance the impact of CDS, although this fi nding was limited to one investigation. Conversely, educational interventions to improve physician adherence to best practice approaches were less effective than CDS, with only 1 study describing a signifi cant decrease in CTPA use or increase in diagnostic yield. Although safety data were limited, in aggregate, the reported studies did not suggest any increase in mortality with interventions to reduce CTPA use. As discussed by the authors, CDS was the most studied and most effective intervention to improve appropriate CTPA use, albeit modest in its impact. The lack of contextual details about what factors made CDS effective or not effective makes it diffi cult to make general recommendations. One cited study did include physician reasons for not embracing CDS, which are not surprising in nature and refl ect concerns about impaired effi ciency and preference for native clinical judgement over that of electronic tools. Moving forward, CDS, perhaps coupled with performance feedback, seems to offer the best hope of reducing inappropriate CTPA use. The growing use of electronic medical records, which is accelerated in the United States by the meaningful use provisions of the Health Information Technology for Economic and Clinical Health Act of 2009, implies that CDS tools are going to be implemented across the spectrum of diagnoses, including that of PE.13 The goals of CDS interventions, namely improved patient safety, quality, and cost-effectiveness, are more likely to be achieved if those studying and designing these electronic tools understand the day-to-day practice of clinical medicine. As summarized by Bates and colleagues14 in the “Ten Commandments for Effective Clinical Decision Support,” CDS interventions will be successful in changing physician behavior and promoting the right test or treatment only if they seamlessly fi t into the clinical workfl ow, have no impact on (or improve upon) physician effi ciency, and minimize the need for additional information from the user. As suggested by Deblois et al.,12 future studies of CDS interventions that aim to align CTPA use with recommended best practices should incorporate more rigorous methodological quality, include safety and cost-effectiveness outcomes, and, perhaps most *Address for correspondence and reprint requests: Jason A. Stamm, MD, Geisinger Medicine Center, Pulmonary and Critical Care Medicine, 100 North Academy Drive, Box 20-37, Danville, PA 17821; Telephone: 570-271-6389; Fax: 570-271-6021; E-mail: jastamm@geisinger.edu

Echocardiography-Defined Pulmonary Hypertension in Multiple Myeloma: Risk Factors and Impact on Outcomes.

Objectives Survival of patients with multiple myeloma (MM) has improved as a result of therapeutic advances. There is evidence that some patients with MM develop pulmonary hypertension (PH). The objective of this study was to identify risk factors of echocardiographic PH and its impact on outcomes of patients with MM. Methods We conducted a retrospective study of patients with MM (N = 359) diagnosed between 2000 and 2011 within the Geisinger Medical Center. Chart review was conducted on the subgroup of patients who underwent a transthoracic echocardiogram within 2 years of being diagnosed as having MM. Results A total of 34% of patients (N = 123/359) underwent transthoracic echocardiogram and 32% (N = 39/123) had echocardiography-defined PH. PH was significantly associated with older age (70.5 vs 65.3 years; P = 0.019), greater left atrial diameter (4.0 vs 3.7 cm; P = 0.025), and a trend toward decreased renal function. PH was not associated with myeloma-specific features. Fewer patients with PH underwent hematopoietic stem cell transplantation compared with those without PH (10% vs 30%; P = 0.018). There was no significant difference in survival between the PH and non-PH groups (P = 0.2775). Conclusions Echocardiography-defined PH was found in a sizeable minority of our MM cohort. Although the specific etiology of PH can be determined only through a prospective clinical evaluation, including right heart catheterization, our results suggest that PH in patients with MM is secondary to left heart disease and perhaps impaired renal function. Patients with PH were significantly less likely to undergo hematopoietic stem cell transplantation. Future studies should assess the etiology of PH, its impact on treatment decisions, and prognosis of patients with MM.

Risk Stratification for Acute Pulmonary Embolism

Pulmonary embolism (PE) is a commonly encountered condition in the medical and surgical intensive care unit. Whereas overall mortality in those with PE is 5% to 15% in the first few months after diagnosis due to a combination of underlying medical conditions, recurrent venous thromboembolism and right heart failure, outcomes after acute PE vary substantially across subgroups. Patients who present with shock uffer from an approximate 25% to 50% short-term mortality rate, whereas those with reserved blood pressure at presentation experience only a 2% to 5% risk of eath. Despite this understanding of the spectrum of prognoses in those with acute PE, there remains much uncertainty in how best to align the risk of adverse outcome in acute PE with the appropriate intensity of therapeutic intervention. Apart from those who present in shock and immediately declare their prognosis, which patients with acute PE are at low risk of adverse outcomes and do not require a higher level of care? Which patients are at an elevated risk of clinical deterioration and should be treated in the intensive care unit and perhaps considered for thrombolytic therapy? An understanding of the pathophysiology of acute PE is essential to risk stratification. Outcome in acute PE is dependent on the presence of preexisting comorbidities and the extent of hemodynamic compromise. Specifically, in the context of any underlying cardiopulmonary disease, the ability of the right ventricle (RV) to compensate for an increase in pulmonary vascular resistance is the major determinant of survival. The resistance to flow from the RV in acute PE is multifactorial and includes not only mechanical obstruction of the proximal pulmonary arteries by acute and/or recurrent thrombus but also the actions of humoral factors that are released from the clot, resulting in pulmonary vasoconstriction. In addition, the hypoxemia that results from impaired ventilation/perfusion matching further increases pulmonary vascular resistance. Acutely, the RV can only compensate for a mean pulmonary artery pressure of approximately 40 mmHg, whereas much higher pulmonary pressures are tolerated if pulmonary hypertension (PH) occurs more gradually. With