Impact of body position on hemodynamic measurements during exercise: A tale of two bikes.

The addition of exercise testing during right heart catheterization (RHC) is often required to accurately diagnose causes of exercise intolerance like early pulmonary vascular disease, occult left heart disease, and preload insufficiency. We tested the influence of body position (supine vs. seated) on hemodynamic classification both at rest and during exercise. We enrolled patients with exercise intolerance due to dyspnea who were referred for exercise RHC at the Cleveland Clinic. Patients were randomized (1:1) to exercise in seated or supine position to a goal of 60 W followed by maximal exercise in the alternate position. We analyzed 17 patients aged 60.3 ± 10.9 years, including 13 females. At rest in the sitting position, patients had significantly lower right atrial pressure (RAP), mean pulmonary artery pressure (mPAP), pulmonary artery wedge pressure (PAWP) and cardiac index (CI). In every stage of exercise (20, 40, and 60 W), the RAP, mPAP, and PAWP were lower in the sitting position. Exercise in the sitting position allowed the identification of preload insufficiency in nine patients. Exercise in either position increased the identification of postcapillary pulmonary hypertension (PH). Body position significantly influences hemodynamics at rest and with exercise; however, mPAP/CO and PAWP/CO were not positionally affected. Hemodynamic measurements in the seated position allowed the detection of preload insufficiency, a condition that was predominantly identified as no PH during supine exercise.

An Incidental Finding of Pulmonary Cement Embolism Four Weeks After Vertebroplasty in a 50-Year-Old Man with Multiple Myeloma.

BACKGROUND Vertebroplasty is a minimally invasive radiological procedure that involves injection of cement to stabilize the fractured vertebra. It has also been increasingly used to relieve pain in patients with bone-incorporated malignancies. The most frequently encountered complication of this procedure is inadvertent cement leakage, which has the potential to embolize. This report presents an incidental finding of cement embolism during fluoroscopy for a peripherally inserted central catheter (PICC) line 4 weeks after vertebroplasty in a 50-year-old man with multiple myeloma. CASE REPORT Our report details the case of a 50-year-old man who presented for progressive sciatic nerve pain and was found on imaging to have an L3 fracture, spinal stenosis, lumbar spinal spondylosis, and diffusely decreased bone density, eventually diagnosed with multiple myeloma. For symptomatic relief and vertebrae stabilization, he underwent a CT-guided fluoroscopic vertebroplasty procedure. Four weeks later, during fluoroscopy for a PICC, he was incidentally found to have radiopaque opacities within the pulmonary arteries. He was diagnosed with a pulmonary embolism due to transvertebral cement leakage from his vertebroplasty. Given the central nature of his embolism, he was treated with anticoagulation and closely monitored. Throughout the treatment period, he remained asymptomatic with normal vital signs and NT-brain natriuretic peptide. CONCLUSIONS This report highlights the association between vertebroplasty and pulmonary cement embolism (PCE), the potential for late detection upon chest imaging even weeks after vertebroplasty, and suggests that some patients with PCE may need therapeutic anticoagulation.

Systemic Inflammatory Response Syndrome After Extracorporeal Membrane Oxygenation Decannulation in COVID-19 Patients.

INTRODUCTION: Systemic inflammatory response syndrome (SIRS) is frequently observed following decannulation from extracorporeal membrane oxygenation (ECMO). Differentiating cytokine release due to infection from endothelial injury from cannula removal and/or discontinuation from the ECMO circuit has been shown to impact treatment and outcomes. This response, however, may be complicated in COVID-19 patients due to prevalent glucocorticoid and immune modulator use. It remains unclear whether COVID-19 infection and/or associated immune modulator use impact the incidence of SIRS following decannulation. OBJECTIVES: The aim of this study is to investigate the incidence of the SIRS phenomenon and associated outcomes in patients with COVID-19 after ECMO decannulation. METHODS: An IRB-approved retrospective chart review of all patients who survived ECMO between June 31, 2010 and July 7, 2021 was done to identify patients who experienced SIRS within 48 hours of decannulation from ECMO support. Patients with COVID-19 were confirmed by a positive reverse transcription polymerase chain reaction (RT-PCR) assay for SARS-CoV2. SIRS was confirmed when two out of three of the following criteria were met: fever, leukocytosis, and/or initiation/escalation of vasopressors. Patients who developed post-ECMO SIRS were then distinguished based on the presence of infection. Infection was defined by the presence of either a new or positive culture following decannulation. We compared the incidence of SIRS and infection within 48 hours of decannulation in patients with and without COVID-19. RESULTS: We identified 227 eligible patients who survived ECMO. Twenty-eight patients (12%) had COVID-19. Of these patients, ten patients with COVID-19 (36%) experienced post-ECMO SIRS, including those with true SIRS (n=3) and associated infections (n=7). Five of the ten patients with COVID-19 who experienced post-ECMO SIRS were exposed to immune modulators within two weeks of decannulation. Ninety-five (42%) patients without COVID-19 developed post-ECMO SIRS. Thirty-day survival in COVID patients who experienced post-ECMO SIRS compared to COVID patients who did not experience post-ECMO SIRS was 73% vs. 94%. (p=0.11). CONCLUSION: Post-ECMO SIRS is common. The incidence of SIRS following decannulation was similar when historically compared to non-COVID patients who survived ECMO in a previously reported cohort from our institution. Immune-modulation exposure within two weeks of decannulation did not affect the incidence of SIRS in patients with COVID-19.

A Framework for Developing a Multidisciplinary Approach to Prone Positioning in Acute Respiratory Distress Syndrome.

Prone position ventilation (PPV) is one of the few interventions with a proven mortality benefit in the management of acute respiratory distress syndrome (ARDS), yet it is underutilized as demonstrated by multiple large observational studies. Significant barriers to its consistent application have been identified and studied. But the complex interplay of a multidisciplinary team makes its consistent application challenging. We present a framework of multidisciplinary collaboration that identifies the appropriate patients for this intervention and discuss our institutional experience applying a multidisciplinary team to implement prone position (PP) leading up to and through the current COVID-19 pandemic. We also highlight the role of such multidisciplinary teams in the effective implementation of prone positioning in ARDS throughout a large health care system. We emphasize the importance of proper selection of patients and provide guidance on how a protocolized approach can be utilized for proper patient selection.

Outcomes of extracorporeal membrane oxygenation in immunosuppressed vs. Immunocompetent patients.

INTRODUCTION: Immunosuppressed hosts represent a growing group of patients who suffer acute respiratory failure and may be considered for therapies such as extracorporeal membrane oxygenation (ECMO). OBJECTIVES: We conducted this retrospective study to determine whether acutely or chronically immunosuppressed patients placed on ECMO for cardiac and/or respiratory failure in our institution have different outcomes than immunocompetent patients placed on ECMO in our institution. METHODS: Adult patients placed on ECMO between June 31, 2010 and July 7, 2021 were identified within an IRB-approved database. Data was retrospectively extracted from the database and patients' medical records. Patients who survived ECMO decannulation were sub-grouped by the presence of acute or chronic immunosuppression, defined by the use of high-dose steroids or immunosuppressive agents for greater than four weeks prior to ECMO initiation. We analyzed and compared baseline characteristics and clinical outcomes using chi-squared tests for categorical variables and a one-way analysis of variance (ANOVA) for continuous variables. RESULTS: 385 patients were included in this study, with 39 identified as chronically immunosuppressed, 49 as acutely immunosuppressed, and 297 as immunocompetent. There was no statistical difference in ECMO survival (respectively 54%, 59%, 65% p = 0.359) or 30-day survival (33%, 51%, 48% p = 0.149) for chronically immunosuppressed, acutely immunosuppressed, and immunocompetent, respectively. There were significant differences in rates of pre-ECMO COVID infection (p<0.001), coronary artery disease (p<0.001), smoking (p = 0.003), and acute kidney injury (p = 0.032). Acutely immunosuppressed patients had the highest rates of new infections during ECMO (p = 0.006). CONCLUSION: When compared to immunocompetent patients, both acutely and chronically immunosuppressed patients had no significant difference in ECMO survival or 30-day survival. Acutely immunosuppressed patients had less comorbidities than chronically immunosuppressed patients, but they were more commonly infected during ECMO. ECMO may still be a valuable tool in appropriately selected patients with refractory respiratory or cardiac failure.

68-year old man with progressive weakness and ventilator dependent respiratory failure: a case report of sporadic late onset nemaline myopathy.

BACKGROUND: Neuromuscular pathologies must be considered when caring for patients with persistent or progressive respiratory failure. Pertinent disease states may involve skeletal muscles of respiration or associated neurologic structures including motor neurons, peripheral neurons and the neuromuscular junction. Diagnosis may require pulmonary function testing, neurophysiologic studies, imaging, and/or muscle biopsy. CASE PRESENTATION: A 68-year-old male was transferred to our intensive care unit (ICU) for management of ventilator dependent respiratory failure. Upon further historical review, he described gradually worsening gait instability and muscle weakness, which was previously attributed to vascular Parkinsonism in the setting of known cerebrovascular disease. Upon arrival to our hospital, he was found to have elevated muscle specific enzymes, prompting evaluation for neuromuscular causes of respiratory failure. He was also found to have elevated HMG-CoA Reductase (HMGCR) antibodies. Ultimately, a right quadriceps muscle biopsy was performed and electron microscopy identified nemaline bodies within skeletal myofibers. Given the clinical course and other histopathologic findings, he was diagnosed with Sporadic late-onset nemaline myopathy (SLONM). CONCLUSION: The diagnosis of neuromuscular disease in patients with ventilator dependent respiratory failure is challenging. A detailed history of a patient's clinical course prior to hospitalization is key and may raise suspicion for underlying neuromuscular pathology. Further evaluation in non-critically ill patients may include pulmonary function, electromyography and confirmatory muscle biopsy. Sporadic late onset nemaline myopathy remains a rare disease entity which rarely presents with respiratory failure and lacks effective treatment.