Evolution of distal limb perfusion management in adult peripheral venoarterial extracorporeal membrane oxygenation with femoral artery cannulation.

Limb ischaemia is a clinically relevant complication of venoarterial extracorporeal membrane oxygenation (VA ECMO) with femoral artery cannulation. No selective distal perfusion or other advanced techniques were used in the past to maintain adequate distal limb perfusion. A more recent trend is the shift from the reactive or emergency management to the pro-active or prophylactic placement of a distal perfusion cannula to avoid or reduce limb ischaemia-related complications. Multiple alternative cannulation techniques to the distal perfusion cannula have been developed to maintain distal limb perfusion, including end-to-side grafting, external or endovascular femoro-femoral bypass, retrograde limb perfusion (e.g., via the posterior tibial, dorsalis pedis or anterior tibial artery), and, more recently, use of a bidirectional cannula. Venous congestion has also been recognized as a potential contributing factor to limb ischaemia development and specific techniques have been described with facilitated venous drainage or bilateral cannulation being the most recent, to reduce or avoid venous stasis as a contributor to impaired limb perfusion. Advances in monitoring techniques, such as near-infrared spectroscopy and duplex ultrasound analysis, have been applied to improve decision-making regarding both the monitoring and management of limb ischaemia. This narrative review describes the evolution of techniques used for distal limb perfusion during peripheral VA ECMO.

Association between Age and Mortality in Pediatric and Adult Acute Respiratory Distress Syndrome.

Rationale: The epidemiology, management, and outcomes of acute respiratory distress syndrome (ARDS) differ between children and adults, with lower mortality rates in children despite comparable severity of hypoxemia. However, the relationship between age and mortality is unclear.Objective: We aimed to define the association between age and mortality in ARDS, hypothesizing that it would be nonlinear.Methods: We performed a retrospective cohort study using data from two pediatric ARDS observational cohorts (n = 1,236), multiple adult ARDS trials (n = 5,547), and an adult observational ARDS cohort (n = 1,079). We aligned all datasets to meet Berlin criteria. We performed unadjusted and adjusted logistic regression using fractional polynomials to assess the potentially nonlinear relationship between age and 90-day mortality, adjusting for sex, PaO2/FiO2, immunosuppressed status, year of study, and observational versus randomized controlled trial, treating each individual study as a fixed effect.Measurements and Main Results: There were 7,862 subjects with median ages of 4 years in the pediatric cohorts, 52 years in the adult trials, and 61 years in the adult observational cohort. Most subjects (43%) had moderate ARDS by Berlin criteria. Ninety-day mortality was 19% in the pediatric cohorts, 33% in the adult trials, and 67% in the adult observational cohort. We found a nonlinear relationship between age and mortality, with mortality risk increasing at an accelerating rate between 11 and 65 years of age, after which mortality risk increased more slowly.Conclusions: There was a nonlinear relationship between age and mortality in pediatric and adult ARDS.

Spontaneous middle lobe torsion: An institutional case series.

Objective: Lobar torsion is a rare occurrence in which a portion of the lung is twisted on its bronchovascular pedicle. The vast majority are observed in the acute postoperative period often following right upper lobectomy. Spontaneous middle lobe torsion independent of pulmonary resection is exceptionally rarer; fewer than 15 cases have been recorded. We present an institutional case series of 2 patients postorthotopic liver transplantation who developed spontaneous middle lobe torsion due to large pleural effusions. Methods: We provide the medical course as well as intraoperative techniques for our 2 patients along with a review of the literature. Results: Both patients in this case series underwent orthotopic liver transplant complicated postoperatively by a large pulmonary effusion. Patient one developed an abdominal hematoma requiring evacuation and repair, after which he developed progressive shortness of breath. Bronchoscopy revealed a right middle lobe obstruction; upon thoracotomy, 180-degree torsion with widespread necrosis was evident and the middle lobe was removed. He is doing well to date. Patient 2 experienced postoperative pleural effusion and mucus plugging; computed tomography revealed abrupt middle lobe arterial occlusion prompting urgent operative intervention. Again, the middle lobe was grossly ischemic and dissection revealed a 360-degree torsion around the pedicle. It was resected. He is doing well to date. Conclusions: As the result of its rarity, radiographic and clinical diagnosis of spontaneous pulmonary lobar torsion is challenging; a high index of suspicion for spontaneous middle lobe torsion must be maintained to avoid delays in diagnosis. Prompt surgical intervention is essential to improve patient outcomes.

Effects of COVID-19 on Pregnant Women and Newborns: A Review.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus originated in Wuhan, China, and spread all over the world, causing the worst pandemic of the century. The disease has a broad continuum of clinical presentations, from mild to life-threatening. The virus is highly contagious and transmittable to humans. Emerging evidence of its effects on pregnant women and newborns is inconsistent and ever-evolving. Therefore, the objective of this review is to compile the scientific literature on the effects of SARS-CoV-2 coronavirus on pregnancy, pregnant women, and newborns. Data were obtained by several authors using PubMed, MEDLINE, Google Scholar, and Web of Science. "COVID-19", "pregnancy", "vertical transmission", and "newborn" were the search words used to find relevant articles. Most studies suggested pregnant women and newborns are not at additional risk for unfavorable outcomes. Besides, very few studies found newborns who tested positive for SARS-CoV-2 upon delivery from a COVID-positive mother. However, several studies showed no evidence of intrauterine or transplacental transmission of COVID-19 infection. Studies had mixed findings with a few showing the presence of the virus in breastmilk. In conclusion, there is no concrete evidence of additional adverse effects of SARS-CoV-2 on pregnant women and newborns.

Obesity: A Chronic Low-Grade Inflammation and Its Markers.

As the prevalence of obesity continues to rise, the world is facing a major public health concern. Obesity is a complex disease associated with an increase in several inflammatory markers, leading to chronic low-grade inflammation. Of multifactorial etiology, it is often used as a measurement of morbidity and mortality. There remains much unknown regarding the association between obesity and inflammation. This review seeks to compile scientific literature on obesity and its associated inflammatory markers in chronic disease and further discusses the role of adipose tissue, macrophages, B-cells, T-cells, fatty acids, amino acids, adipokines, and hormones in obesity. Data were obtained using PubMed and Google Scholar. Obesity, inflammation, immune cells, hormones, fatty acids, and others were search words used to acquire relevant articles. Studies suggest brown adipose tissue is negatively associated with body mass index (BMI) and body fat percentage. Researchers also found the adipose tissue of lean individuals predominantly secretes anti-inflammatory markers, while in obese individuals more pro-inflammatory markers are secreted. Many studies found that adipose tissue in obese individuals showed a shift in immune cells from anti-inflammatory M2 macrophages to pro-inflammatory M1 macrophages, which was also correlated with insulin resistance. Obese individuals generally present with higher levels of hormones such as leptin, visfatin, and resistin. With obesity on the rise globally, it is predicted that severe obesity will become most common amongst low-income adults, black individuals, and women by 2030, making the need for intervention urgent. Further investigation into the association between obesity and inflammation is required to understand the mechanism behind this disease.

Utilization of Veno-Arterial Extracorporeal Life Support for Acute Respiratory Distress Syndrome After Liver Transplant.

In this report, we present a case of successful long-term salvage of a patient with transfusion-related acute lung injury associated with acute respiratory distress syndrome immediately after a liver transplant. The patient was a 29-year-old man with end-stage liver disease due to sclerosing cholangitis who underwent liver transplant. After organ reperfusion, there was evidence of liver congestion, acidosis, coagulopathy, and acute kidney injury. He received 61 units of blood products. Continuous renal replacement therapy was initiated intraoperatively. On arrival to the intensive care unit, the patient was on high-dose pressors, and the patient developed respiratory failure and was immediately placed on veno-arterial extracorporeal membrane oxygenation via open femoral exposure. The patient presented with severe coagulopathy and early allograft dysfunction; therefore, no systemic heparin was administered and no thrombotic events occurred. He required extracorporeal membrane oxygenation support until posttransplant day 4, when resolution of the respiratory and cardiac dysfunction was noted. At 2 years after liver transplant, the patient has normal liver function, normal cognitive function, and stage V chronic kidney disease. We conclude that extracorporeal membrane oxygenation is a valuable therapeutic approach in patients with cardiorespiratory failure after liver transplant.

Practical Considerations for and Outcomes of Interfacility ECMO Transfer of Patients With COVID-19 During a Pandemic: Mayo Clinic Experience.

Interfacility transport of a critically ill patient with acute respiratory distress syndrome (ARDS) may be necessary for a higher level of care or initiation of extracorporeal membrane oxygenation (ECMO). During the COVID-19 pandemic, ECMO has been used for patients with severe ARDS with successful results. Transporting a patient after ECMO cannulation by the receiving facility brings forth logistic challenges, including availability of adequate personal protective equipment for the transport team and hospital capacity management issues. We report our designated ECMO transport team's experience of 5 patients with COVID-19-associated severe ARDS after cannulation at the referring facility. Focusing on transport-associated logistics, creation of checklists, and collaboration with emergency medical services partners is necessary for safe and good outcomes for patients while maintaining team safety.

Peripherally inserted central catheter placement in a multidisciplinary intensive care unit: A preliminary study demonstrating safety and procedural time in critically ill subjects.

OBJECTIVE: Peripherally inserted central catheters are a popular means of obtaining central venous access in critically ill patients. However, there is limited data regarding the rapidity of the peripherally inserted central catheter procedure in the presence of acute illness or obesity, both of which may impede central venous catheter placement. We aimed to determine the feasibility, safety, and duration of peripherally inserted central catheter placement in critically ill patients, including obese patients and patients in shock. METHODS: This retrospective cohort study was performed using data on 55 peripherally inserted central catheters placed in a 30-bed multidisciplinary intensive care unit in Mayo Clinic Hospital, Phoenix, Arizona. Information on the time required to complete each step of the peripherally inserted central catheter procedure, associated complications, and patient characteristics was obtained from a prospectively assembled internal quality assurance database created through random convenience sampling. RESULTS: The Median Procedure Time, beginning with the first needle puncture and ending when the procedure is complete, was 14 (interquartile range: 9-20) min. Neither critical illness nor obesity resulted in a statistically significant increase in the time required to complete the peripherally inserted central catheter procedure. Three (5.5%) minor complications were observed. CONCLUSION: Critical illness and obesity do not delay the acquisition of vascular access when placing a peripherally inserted central catheter. Concerns of delayed vascular access in critically ill patients should not deter a physician from selecting a peripherally inserted central catheter to provide vascular access when it would otherwise be appropriate.

Using critical care physicians to deliver anesthesia and boost surgical caseload in austere environments: the Critical Care General Anesthesia Syllabus (CC GAS).

BACKGROUND: Despite an often severe lack of surgeons and surgical equipment, the rate-limiting step in surgical care for the nearly five billion people living in resource-limited areas is frequently the absence of safe anesthesia. During disaster relief and surgical missions, critical care physicians (CCPs), who are already competent in complex airway and ventilator management, can help address the need for skilled anesthetists in these settings. METHODS: We provided a descriptive analysis that CCPs were trained to provide safe general anesthesia, monitored anesthesia care (MAC), and spinal anesthesia using a specifically designed and simple syllabus. RESULTS: Six CCPs provided anesthesia under the supervision of a board-certified anesthesiologist for 58 (32%) cases of a total of 183 surgical cases performed by a surgical mission team at St. Luc Hospital in Port-au-Prince, Haiti in 2013, 2017, and 2018. There were no reported complications. CONCLUSIONS: Given CCPs' competencies in complex airway and ventilator management, a CCP, with minimal training from a simple syllabus, may be able to act as an anesthesiologist-extender and safely administer anesthesia in the austere environment, increasing the number of surgical cases that can be performed. Further studies are necessary to confirm our observation.

Physician-Assisted Suicide and Euthanasia in the ICU: A Dialogue on Core Ethical Issues.

OBJECTIVE: Many patients are admitted to the ICU at or near the end of their lives. Consequently, the increasingly common debate regarding physician-assisted suicide and euthanasia holds implications for the practice of critical care medicine. The objective of this article is to explore core ethical issues related to physician-assisted suicide and euthanasia from the perspective of healthcare professionals and ethicists on both sides of the debate. SYNTHESIS: We identified four issues highlighting the key areas of ethical tension central to evaluating physician-assisted suicide and euthanasia in medical practice: 1) the benefit or harm of death itself, 2) the relationship between physician-assisted suicide and euthanasia and withholding or withdrawing life support, 3) the morality of a physician deliberately causing death, and 4) the management of conscientious objection related to physician-assisted suicide and euthanasia in the critical care setting. We present areas of common ground and important unresolved differences. CONCLUSIONS: We reached differing positions on the first three core ethical questions and achieved unanimity on how critical care clinicians should manage conscientious objections related to physician-assisted suicide and euthanasia. The alternative positions presented in this article may serve to promote open and informed dialogue within the critical care community.

Science of Health Care Delivery: An Innovation in Undergraduate Medical Education to Meet Society's Needs.

The purpose of this special article is to describe a new, 4-year Science of Health Care Delivery curriculum at Mayo Clinic School of Medicine, including curricular content and structure, methods for instruction, partnership with Arizona State University, and implementation challenges. This curriculum is intended to ensure that graduating medical students enter residency prepared to train and eventually practice within person-centered, community- and population-oriented, science-driven, collaborative care teams delivering high-value care. A Science of Health Care Delivery curriculum in undergraduate medical education is necessary to successfully prepare physicians so as to ensure the best clinical outcomes and patient experience of care, at the lowest cost.

The utility of live video capture to enhance debriefing following transcatheter aortic valve replacement.

BACKGROUND: The surgical and procedural specialties are continually evolving their methods to include more complex and technically difficult cases. These cases can be longer and incorporate multiple teams in a different model of operating room synergy. Patients are frequently older, with comorbidities adding to the complexity of these cases. Recording of this environment has become more feasible recently with advancement in video and audio capture systems often used in the simulation realm. AIMS: We began using live capture to record a new procedure shortly after starting these cases in our institution. This has provided continued assessment and evaluation of live procedures. The goal of this was to improve human factors and situational challenges by review and debriefing. SETTING AND DESIGN: B-Line Medical's LiveCapture video system was used to record successive transcatheter aortic valve replacement (TAVR) procedures in our cardiac catheterization/laboratory. An illustrative case is used to discuss analysis and debriefing of the case using this system. RESULTS AND CONCLUSIONS: An illustrative case is presented that resulted in long-term changes to our approach of these cases. The video capture documented rare events during one of our TAVR procedures. Analysis and debriefing led to definitive changes in our practice. While there are hurdles to the use of this technology in every institution, the role for the ongoing use of video capture, analysis, and debriefing may play an important role in the future of patient safety and human factors analysis in the operating environment.

Mechanical circulatory assist devices: a primer for critical care and emergency physicians.

Mechanical circulatory assist devices are now commonly used in the treatment of severe heart failure as bridges to cardiac transplant, as destination therapy for patients who are not transplant candidates, and as bridges to recovery and "decision-making". These devices, which can be used to support the left or right ventricles or both, restore circulation to the tissues, thereby improving organ function. Left ventricular assist devices (LVADs) are the most common support devices. To care for patients with these devices, health care providers in emergency departments (EDs) and intensive care units (ICUs) need to understand the physiology of the devices, the vocabulary of mechanical support, the types of complications patients may have, diagnostic techniques, and decision-making regarding treatment. Patients with LVADs who come to the ED or are admitted to the ICU usually have nonspecific clinical symptoms, most commonly shortness of breath, hypotension, anemia, chest pain, syncope, hemoptysis, gastrointestinal bleeding, jaundice, fever, oliguria and hematuria, altered mental status, headache, seizure, and back pain. Other patients are seen for cardiac arrest, psychiatric issues, sequelae of noncardiac surgery, and trauma. Although most patients have LVADs, some may have biventricular support devices or total artificial hearts. Involving a team of cardiac surgeons, perfusion experts, and heart-failure physicians, as well as ED and ICU physicians and nurses, is critical for managing treatment for these patients and for successful outcomes. This review is designed for critical care providers who may be the first to see these patients in the ED or ICU.

Adult venovenous extracorporeal membrane oxygenation for severe respiratory failure: Current status and future perspectives.

Extracorporeal membrane oxygenation (ECMO) for severe acute respiratory failure was proposed more than 40 years ago. Despite the publication of the ARDSNet study and adoption of lung protective ventilation, the mortality for acute respiratory failure due to acute respiratory distress syndrome has continued to remain high. This technology has evolved over the past couple of decades and has been noted to be safe and successful, especially during the worldwide H1N1 influenza pandemic with good survival rates. The primary indications for ECMO in acute respiratory failure include severe refractory hypoxemic and hypercarbic respiratory failure in spite of maximum lung protective ventilatory support. Various triage criteria have been described and published. Contraindications exist when application of ECMO may be futile or technically impossible. Knowledge and appreciation of the circuit, cannulae, and the physiology of gas exchange with ECMO are necessary to ensure lung rest, efficiency of oxygenation, and ventilation as well as troubleshooting problems. Anticoagulation is a major concern with ECMO, and the evidence is evolving with respect to diagnostic testing and use of anticoagulants. Clinical management of the patient includes comprehensive critical care addressing sedation and neurologic issues, ensuring lung recruitment, diuresis, early enteral nutrition, treatment and surveillance of infections, and multisystem organ support. Newer technology that delinks oxygenation and ventilation by extracorporeal carbon dioxide removal may lead to ultra-lung protective ventilation, avoidance of endotracheal intubation in some situations, and ambulatory therapies as a bridge to lung transplantation. Risks, complications, and long-term outcomes and resources need to be considered and weighed in before widespread application. Ethical challenges are a reality and a multidisciplinary approach that should be adopted for every case in consideration.

Building surgical capacity in developing countries: lessons from Haiti and Honduras.

The unmet burden of surgical disease in developing countries is large and growing. We successfully initiated two surgical field hospitals in austere environments. Similar problems were encountered in the areas of facility development, operations, and social considerations. A literature review was performed to contextualize our experience and compare it with that of others.

Regional perfusion during venoarterial extracorporeal membrane oxygenation: a case report and educational modules on the concept of dual circulations.

UNLABELLED: A challenging aspect of managing patients on venoarterial extracorporeal membrane oxygenation (V-A ECMO) is a thorough understanding of the relationship between oxygenated blood from the ECMO circuit and blood being pumped from the patient's native heart. We present an adult V-A ECMO case report, which illustrates a unique encounter with the concept of "dual circulations." Despite blood gases from the ECMO arterial line showing respiratory acidosis, this patient with cardiogenic shock demonstrated regional respiratory alkalosis when blood was sampled from the right radial arterial line. In response, a sample was obtained from the left radial arterial line, which mimicked the ECMO arterial blood but was dramatically different from the blood sampled from the right radial arterial line. A retrospective analysis of patient data revealed that the mismatch of blood gas values in this patient corresponded to an increased pulse pressure. Having three arterial blood sampling sites and data on the patient's pulse pressure provided a dynamic view of blood mixing and guided proper management, which contributed to a successful patient outcome that otherwise may not have occurred. As a result of this unique encounter, we created and distributed graphics representing the concept of "dual circulations" to facilitate the education of ECMO specialists at our institution. KEYWORDS: ECMO, education, cardiopulmonary bypass, cannulation.

Hyperammonemic Coma in an Adult due to Ornithine Transcarbamylase Deficiency.

Objective. To report an unusual cause of coma in an adult. Design. Case report. Setting. University teaching hospital. Patient. A previously healthy 53-year-old man initially presented with altered mental status and progressed to coma. He was found to be substantially hyperammonemic and did not improve with lactulose therapy and continuous venovenous hemodialysis. Results. Biochemical testing revealed previously undiagnosed ornithine transcarbamylase deficiency, and the patient responded to arginine, sodium phenylacetate, and sodium benzoate. Conclusion. Even in adult patients with no known history, inborn errors of metabolism must be considered in the differential diagnosis of unexplained coma. Defects of the urea cycle can present with an unprovoked hyperammonemic coma.

Urologic surgical simulation: an endoscopic bladder model.

INTRODUCTION: With the explosion of endoscopic techniques in urology as well as the increasing work restrictions with resident duty hours, training programs are faced with the challenges of how to adequately train residents while still being proficient and safe in the operating room. Surgical simulation with models is an excellent tool to help bridge the gap between practice and experience and allow residents to learn basic skills in a low stress environment that can be later transferred to the operating room. METHODS: We present a high-fidelity endoscopic boar bladder model for first-year urology resident training in preparation for real-time experience in the operating room. RESULTS: The boar bladder model held up for the residents to complete six separate tasks. In each of the six assigned tasks, both residents had a percent improvement ranging from 13% to 97% when comparing an average of the first attempts with the final attempt. CONCLUSIONS: The novel simulation model we describe demonstrates is a high-fidelity tissue surrogate that can be used for simulation training for improvement in core urologic skills by novice residents. This model may be a useful tool in documenting proficiency-based competence of cystoscopic skills.