The physiology of extracorporeal membrane oxygenation: The Fick principle

Extracorporeal membrane oxygenation (ECMO) can be delivered in veno-arterial (VA) and veno-venous (VV) configurations based on the cannulation strategy. VA and VV ECMO are delivered primarily for haemodynamic and respiratory support in patients with severe heart and lung failure, respectively. The Fick principle describes the relationship between blood flow and oxygen consumption – key parameters in the physiological management of extracorporeal support. This review will discuss the application of the Fick principle in: (i) recirculation in VV ECMO; (ii) the quantification of oxygen delivery (DO2) in VV ECMO and (iii) the quantification of transpulmonary blood flow and systemic arterial oxygen saturation in VA ECMO.

Ambulatory Extracorporeal Membrane Oxygenation: Times Are Changing

During the past century, medical technology has evolved to enhance quality and quantity of life. Medications, surgeries, and implantable devices have been developed and enhanced to reduce complications and improve patient outcomes. The use of extracorporeal membrane oxygenation is one of the most substantial advances in life-saving modalities. Extracorporeal membrane oxygenation has been widely used for patients with heart or lung failure across the lifespan. Expansion and simplifications of extracorporeal membrane oxygenation circuit designs have informed changes in patient treatment (from bed confinement to ambulatory) and shifted many clinical staffing structures (from cardiovascular perfusionist to nurse-managed care). Highly skilled registered nurses and advanced practice registered nurses are increasingly involved in managing extracorporeal membrane oxygenation in the critical care setting. The purpose of this article is to highlight the technological evolution of extracorporeal membrane oxygenation and the corresponding patient care that bedside registered nurses and advanced practice registered nurses provide.

Acute respiratory distress syndrome in COVID-19: possible mechanisms and therapeutic management

COVID-19 pandemic is a serious concern in the new era. Acute respiratory distress syndrome (ARDS), and lung failure are the main lung diseases in COVID-19 patients. Even though COVID-19 vaccinations are available now, there is still an urgent need to find potential treatments to ease the effects of COVID-19 on already sick patients. Multiple experimental drugs have been approved by the FDA with unknown efficacy and possible adverse effects. Probably the increasing number of studies worldwide examining the potential COVID-19 related therapies will help to identification of effective ARDS treatment. In this review article, we first provide a summary on immunopathology of ARDS next we will give an overview of management of patients with COVID-19 requiring intensive care unit (ICU), while focusing on the current treatment strategies being evaluated in the clinical trials in COVID-19-induced ARDS patients.

A randomized clinical trial of home telemonitoring in patients with advanced heart and lung diseases.

Brief Summary The addition of home monitoring to an integrated care model in patients with advanced chronic heart/lung diseases decreases mortality, hospital and emergency admissions, improves functional status, HRQoL, and is cost-effective. Background Telemonitoring is a promising implement for medicine, but its efficacy is unknown in patients with advanced heart and lung failure (AHLF). Objective To determine the efficacy of a telemonitoring system added to coordinated clinical care in patients with AHLF. Design Randomized phase 3 multicenter clinical trial with parallel groups in adult patients. Participants Five spanish centers including patients with AHLF at discharge or in out-patient clinics. Intervention Patients were randomly assigned to receive a remote bio-parameters telemonitoring system (TELECARE) or best usual care (UCARE). TELECARE patients were provided with devices that collected symptoms and bio-parameters, and transferred them synchronously to a call-center, with a real-time health-care response. Main Measures Primary end point was the need of admissions/emergency room visits at 45, 90, 180 days. Secondary end points included health care requirements, mortality, functional assessment, health related quality of life (HRQoL), perceived satisfaction, and cost-efficacy. Results 510 patients were included (54.5% women, median age 76.5 years; 63.1% suffered heart failure, 13.9% lung failure, and 22.9% both conditions). Clinical and functional features were comparable in both arms. TELECARE globally needed less admissions with respect UCARE after 45 days of inclusion (35.4% vs. 46.9%, p < 0.05). This tendency was maintained in the subgroups of patients with multimorbidity (34.2% vs. 46.9%, p < 0.05), intermediate risk of mortality (36.5% vs. 51.1%, p < 0.05), and those included after hospital discharge (34.9% vs. 50.5%, p < 0.01). HRQoL significantly improved (TELECARE/UCARE EuroQol baseline of 56.2 ± 18.2/55.1 ± 19.7, p = 0.054, and 64 ± 19.9/56.3 ± 21.6; p < 0.01 at the end), and perceived satisfaction was also higher (6.77 ± 0.52 vs. 6.62 ± 0.81, p < 0.001; highest possible score = 7). A trend to mortality decrease was also observed (12.9% vs. 19.3%, p = 0.13). TELECARE was cost-efficacious (TELECARE/UCARE QALY 3.94 Euros/0.81Euros). Conclusions The addition of a telemonitoring system to an integrated care model in patients with AHLF decreases hospital and emergency admissions, improves functional status as well as HRQoL, and is cost-efficacious.

Towards an ecological definition of sepsis: a viewpoint

In critically ill patients with sepsis, there is a grave lack of effective treatment options to address the illness-defining inappropriate host response. Currently, treatment is limited to source control and supportive care, albeit with imminent approval of immune modulating drugs for COVID-19-associated lung failure the potential of host-directed strategies appears on the horizon. We suggest expanding the concept of sepsis by incorporating infectious stress within the general stress response of the cell to define sepsis as an illness state characterized by allostatic overload and failing adaptive responses along with biotic (pathogen) and abiotic (e.g., malnutrition) environmental stress factors. This would allow conceptualizing the failing organismic responses to pathogens in sepsis with an ancient response pattern depending on the energy state of cells and organs towards other environmental stressors in general. Hence, the present review aims to decipher the heuristic value of a biological definition of sepsis as a failing stress response. These considerations may motivate a better understanding of the processes underlying “host defense failure” on the organismic, organ, cell and molecular levels.

Influence of surgical stabilization of clavicle fractures in multiply-injured patients with thoracic trauma

Thoracic trauma has decisive influence on the outcome of multiply-injured patients and is often associated with clavicle fractures. The affected patients are prone to lung dysfunction and multiple organ failure. A multi-center, retrospective analysis of patient records documented in the TraumaRegister DGU was performed to assess the influence of surgical stabilization of clavicle fractures in patients with thoracic trauma. A total of 3,209 patients were included in the analysis. In 1362 patients (42%) the clavicle fracture was treated operatively after 7.1 ± 5.3 days. Surgically treated patients had a significant reduction in lung failure (p = 0.013, OR = 0.74), multiple organ failure (p = 0.001, OR = 0.64), intubation time (p = 0.004; −1.81 days) and length of hospital stay (p = 0.014; −1.51 days) compared to non-operative treatment. Moreover, surgical fixation of the clavicle within five days following hospital admission significantly reduced the rates of lung failure (p = 0.01, OR = 0.62), multiple organ failure (p = 0.01, OR = 0.59) and length of hospital stay (p = 0.01; −2.1 days). Based on our results, multiply-injured patients with thoracic trauma and concomitant clavicle fracture may benefit significantly from surgical stabilization of a clavicle fracture, especially when surgery is performed within the first five days after hospital admission.

The determinants of survival among adults with cystic fibrosis—a cohort study

Background Cystic fibrosis (CF) is one of the most common autosomal recessive diseases. Factors contributing to disease exacerbations and survival rate of CF patients are type of mutation in the CFTR gene, poor nutritional status, lung failure, and infection development by Pseudomonas aeruginosa. The study aimed to evaluate the relationship between the severity of mutation, nutritional status, lung function, and Pseudomonas aeruginosa prevalence and survival rate in adult patients with cystic fibrosis. Methods A study of 124 (68 ♀ and 56 ♂) adults with CF aged 18–51 years were evaluated for (a) type of mutation in the CFTR gene, (b) nutritional status (BMI), (c) lung function (FEV1%), and (d) Pseudomonas aeruginosa prevalence. For statistical calculations, Kaplan-Meier analysis of survival, chi-squared test for multiple samples, and logistic regression were used. Results The type of mutation (χ2 = 12.73, df = 3, p = 0.005), FEV1% (χ2 = 15.20, df = 2, p = 0.0005), Pseudomonas aeruginosa prevalence (χ2 = 11.48, df = 3, p = 0.009), and BMI (χ2 = 31.08, df = 4, p < 0.000) significantly differentiated the probability of survival of patients with CF. The shortest life expectancy was observed in patients with a severe type of mutation on both alleles, FEV1% < 40, subjects in whom Pseudomonas culture was extensively drug-resistant or pandrug-resistant, and patients whose BMI was lower than 18.5 kg/m2. The period from 30 to 40 years of age was the most critical in CF adults’ lifespan. The risk of adults with CF death doubled with Pseudomonas aeruginosa prevalence (OR = 2.06, 95% CI 1.29; 2.28) and eightfold when the bacteria acquired antibiotic resistance (OR = 8.11, 95% CI 1.67; 38.15). Conclusions All factors included in the study were significantly related to the survival rate of patients with cystic fibrosis.