Physiological and clinical effects of trunk inclination adjustment in patients with respiratory failure: a scoping review and narrative synthesis.

BACKGROUND: Adjusting trunk inclination from a semi-recumbent position to a supine-flat position or vice versa in patients with respiratory failure significantly affects numerous aspects of respiratory physiology including respiratory mechanics, oxygenation, end-expiratory lung volume, and ventilatory efficiency. Despite these observed effects, the current clinical evidence regarding this positioning manoeuvre is limited. This study undertakes a scoping review of patients with respiratory failure undergoing mechanical ventilation to assess the effect of trunk inclination on physiological lung parameters. METHODS: The PubMed, Cochrane, and Scopus databases were systematically searched from 2003 to 2023. INTERVENTIONS: Changes in trunk inclination. MEASUREMENTS: Four domains were evaluated in this study: 1) respiratory mechanics, 2) ventilation distribution, 3) oxygenation, and 4) ventilatory efficiency. RESULTS: After searching the three databases and removing duplicates, 220 studies were screened. Of these, 37 were assessed in detail, and 13 were included in the final analysis, comprising 274 patients. All selected studies were experimental, and assessed respiratory mechanics, ventilation distribution, oxygenation, and ventilatory efficiency, primarily within 60 min post postural change. CONCLUSION: In patients with acute respiratory failure, transitioning from a supine to a semi-recumbent position leads to decreased respiratory system compliance and increased airway driving pressure. Additionally, C-ARDS patients experienced an improvement in ventilatory efficiency, which resulted in lower PaCO2 levels. Improvements in oxygenation were observed in a few patients and only in those who exhibited an increase in EELV upon moving to a semi-recumbent position. Therefore, the trunk inclination angle must be accurately reported in patients with respiratory failure under mechanical ventilation.

Analysis of Vancomycin Dosage and Plasma Levels in Critically Ill Adult Patients Requiring Extracorporeal Membrane Oxygenation (ECMO).

Introduction: Critically ill patients undergoing extracorporeal membrane oxygenation (ECMO) exhibit unique pharmacokinetics. This study aimed to assess the achievement of vancomycin therapeutic targets in these patients. Methods: This retrospective cohort study included patients on ECMO treated with vancomycin between January 2010 and December 2018. Ninety patients were analyzed based on ECMO connection modality, baseline creatinine levels, estimated glomerular filtration rate (eGFR), renal replacement therapy (RRT) requirements, and vancomycin loading dose administration. Results: Twenty-three percent of the patients achieved the therapeutic range defined by baseline levels. No significant differences in meeting the therapeutic goal were found in multivariate analysis considering ECMO cannulation modality, initial creatinine level, initial eGFR, RRT requirement, or loading dose use. All trough levels between 15 and 20 mcg/mL achieved an estimated area under the curve/minimum inhibitory concentration (AUC/MIC) between 400 and 600, almost all trough levels over 10 mcg/mL predicted an AUC/MIC >400. Discussion: Achieving therapeutic plasma levels in these patients remains challenging, potentially due to factors such as individual pharmacokinetics and pathophysiology. A trough plasma level between 12 and 20 estimated the therapeutic AUC/MIC for all models, proposing a possible lower target, maintaining exposure, and potentially avoiding adverse effects. Despite being one of the largest cohorts of vancomycin use in ECMO patients studied, its retrospective nature and single-center focus limits its broad applicability.

Coma Prevalence in Critical Care Units in Chile: Results of a Cross-Sectional Survey on World Coma Day.

BACKGROUND: The purpose of this study was to assess the prevalence of coma among patients in critical care units in Chile. We also aimed to provide insight into the demographic characteristics, etiologies, and complications associated with coma. METHODS: A single day cross-sectional study was conducted through a national survey of public and private hospitals with critical and intensive cardiac care units across Chile. Data were collected using an online questionnaire that contained questions regarding critically ill patients' information, demographic characteristics, etiology and duration of coma, medical complications, and support requirements. RESULTS: A total of 84% of all health facilities answered, accounting for a total of 2,708 patients. The overall coma prevalence was 2.9%. The median age of the comatose patients was 61 years (interquartile range 50-72) and 66.2% were male. The median coma duration was five days (interquartile range 2-9). Cerebral hemorrhage was the most common etiology, followed by severe hypoxic-ischemic encephalopathy, acute ischemic stroke, and traumatic brain injury. A total of 48.1% of coma patients experienced acute and ongoing treatment complications, with pneumonia being the most common complication, and 97.4% required support during comatose management. CONCLUSIONS: This study provides an overview of the prevalence of coma in Chilean critical and cardiac care units. Coma is a common condition. Comatose patients frequently experience medical complications during their hospitalization.

Severe osmotic demyelination syndrome with cortical involvement in the context of severe hyponatremia and central diabetes insipidus: an uncommon presentation of an unusual combination.

BACKGROUND: Osmotic demyelination syndrome (ODS) with cerebral cortical involvement is a rare complication of severe hyponatremia correction. Careful management of hyponatremia is crucial, particularly in patients with risk factors, such as alcohol use disorder and diabetes insipidus. CASE: A patient in his 40s with a history of alcohol use disorder and central diabetes insipidus developed ODS after a 24 mEq/L osmolar increase during the treatment of hyponatremia. The patient's condition progressed into locked-in syndrome and then improved to spastic tetraparesis after cortical basal ganglia ODS improved. DISCUSSION: The differential diagnosis of cortical demyelination includes laminar cortical necrosis, being the interpretation of Apparent Diffusion Coefficient (ADC) MRI sequence is a useful tool.This case underscores the need to investigate and improve diagnosis and treatment strategies in patients with ODS. It also emphasises the significance of careful hyponatremia correction and frequent monitoring, particularly in patients with known risk factors for ODS.

Effects of changes in trunk inclination on ventilatory efficiency in ARDS patients: quasi-experimental study.

BACKGROUND: Trunk inclination from semirecumbent head-upright to supine-flat positioning reduces driving pressure and increases respiratory system compliance in patients with acute respiratory distress syndrome (ARDS). These effects are associated with an improved ventilatory ratio and reduction in the partial pressure of carbon dioxide (PaCO2). However, these physiological effects have not been completely studied, and their mechanisms have not yet been elucidated. Therefore, this study aimed to evaluate the effects of a change in trunk inclination from semirecumbent (45°) to supine-flat (10°) on physiological dead space and ventilation distribution in different lung regions. RESULTS: Twenty-two ARDS patients on pressure-controlled ventilation underwent three 60-min steps in which trunk inclination was changed from 45° (baseline) to 10° (intervention) and back to 45° (control) in the last step. Tunk inclination from a semirecumbent (45°) to a supine-flat (10°) position resulted in a higher tidal volume [371 (± 76) vs. 433 (± 84) mL (P < 0.001)] and respiratory system compliance [34 (± 10) to 41 (± 12) mL/cmH2O (P < 0.001)]. The CO2 exhaled per minute improved from 191 mL/min (± 34) to 227 mL/min (± 38) (P < 0.001). Accordingly, Bohr's dead space ratio decreased from 0.49 (± 0.07) to 0.41 (± 0.06) (p < 0.001), and PaCO2 decreased from 43 (± 5) to 36 (± 4) mmHg (p < 0.001). In addition, the impedance ratio, which divides the ventilation activity of the ventral region by the dorsal region ventilation activity in tidal images, dropped from 1.27 (0.83-1.78) to 0.86 (0.51-1.33) (p < 0.001). These results, calculated from functional EIT images, indicated further ventilation activity in the dorsal lung regions. These effects rapidly reversed once the patient was repositioned at 45°. CONCLUSIONS: A change in trunk inclination from a semirecumbent (45 degrees) to a supine-flat position (10 degrees) improved Bohr's dead space ratio and reduced PaCO2 in patients with ARDS. This effect is associated with an increase in tidal volume and respiratory system compliance, along with further favourable impedance ventilation distribution toward the dorsal lung regions. This study highlights the importance of considering trunk inclination as a modifiable determinant of physiological parameters. The angle of trunk inclination is essential information that must be reported in ARDS patients.

Sistema hospitalario en situación de crisis: implementación de sistema de comando de incidentes para enfrentar pandemia SARS-CoV-2 en Clínica Las Condes, Chile / Implementation of incident command system to deal with SARS-CoV-2 pandemic in Clínica Las Condes, Chile

La pandemia en Chile generó un desafío de modernización y gestión de los Cuidados Intensivos, haciendo necesario que las unidades de pacientes críticos realizaran un aumento de su capacidad hospitalaria, lo que requiere preparar una infraestructura, un equipamiento mínimo, protocolos y un equipo humano preparado y alineado, para garantizar la seguridad y calidad de atención a los pacientes. Una forma de lograrlo es la incorporación de la estrategia militar de Sistema de Comando de Incidentes, utilizado para enfrentar distintos tipos de desastres, con una estructura modular de comando y sus seccionales de trabajo, con diferentes equipos y líderes para hacer frentes a los variados desafíos. El objetivo de este artículo es describir la instauración del sistema de comando de incidentes en un hospital privado, detallando su conformación y los resultados logrados.

The pandemic in Chile has been a real challenge in terms of modernization and management of intensive care. Critical care units have been forced to increase their hospital capacity in terms of infrastructure, equipment, protocols and human team, while guaranteeing safety and high-quality patient care.One approach to achieve this objective is to develop the army strategy called incident command system that has been used to face different types of disaster. A modular command structure is developed based on the creation of teams each lead by an expert in different areas in order to cope with a variety of upcoming challenges.The objective of this article is to describe the setting up of a successful incident command system in a private hospital, detailing its formation and results obtained.

Leptospirosis-associated catastrophic respiratory failure supported by extracorporeal membrane oxygenation.

A previously healthy, 39-year-old obese farmer, arrived hypotensive and tachycardic, with fever, myalgia, headache, abdominal pain, diarrhea, and progressive dyspnea. Ten days before symptoms onset, he was in direct contact with mice and working in a contaminated drain. Patient laboratory showed acute kidney injury and thrombocytopenia. Chest X-ray exhibited bilateral diffuse interstitial infiltrates. First-line empirical antibiotics were started and influenza discarded. Patient evolved with severe respiratory failure, associated with hemoptysis, and rapidly severe hemodynamic compromise. Despite neuromuscular blockade and prone positioning, respiratory failure increased. Accordingly, veno-venous ECMO was initiated, with bilateral femoral extraction and jugular return. After ECMO connection, there was no significant improvement in oxygenation, and low pre-membrane saturations and low arterial PaO2 of the membrane showed that we were out of the limits of the rated flow. Thus, a second membrane oxygenator was installed in parallel. Afterward, oxygenation improved, with subsequent perfusion enhancement. Regarding etiology, due to high suspicion index, Leptospira serology was performed, coming back positive and meropenem was maintained. The patient ultimately recovered and experience excellent outcome. The clinical relevance of the case is the scared evidence of leptospirosis-associated severe respiratory failure treated with ECMO. This experience emphasizes the importance of an optimal support, which requires enough membrane surface and flow for an obese, highly hyperdynamic patient, during this reversible disease. A high index of suspicion is needed for an adequate diagnosis of leptospirosis to implement the correct treatment, particularly in the association of respiratory failure, pulmonary hemorrhage, and an epidemiological-related context.