Pendelluft in hypoxemic patients resuming spontaneous breathing: proportional modes versus pressure support ventilation.

BACKGROUND: Internal redistribution of gas, referred to as pendelluft, is a new potential mechanism of effort-dependent lung injury. Neurally-adjusted ventilatory assist (NAVA) and proportional assist ventilation (PAV +) follow the patient's respiratory effort and improve synchrony compared with pressure support ventilation (PSV). Whether these modes could prevent the development of pendelluft compared with PSV is unknown. We aimed to compare pendelluft magnitude during PAV + and NAVA versus PSV in patients with resolving acute respiratory distress syndrome (ARDS). METHODS: Patients received either NAVA, PAV + , or PSV in a crossover trial for 20-min using comparable assistance levels after controlled ventilation (> 72 h). We assessed pendelluft (the percentage of lost volume from the non-dependent lung region displaced to the dependent region during inspiration), drive (as the delta esophageal swing of the first 100 ms [ΔPes 100 ms]) and inspiratory effort (as the esophageal pressure-time product per minute [PTPmin]). We performed repeated measures analysis with post-hoc tests and mixed-effects models. RESULTS: Twenty patients mechanically ventilated for 9 [5-14] days were monitored. Despite matching for a similar tidal volume, respiratory drive and inspiratory effort were slightly higher with NAVA and PAV + compared with PSV (ΔPes 100 ms of -2.8 [-3.8--1.9] cm H2O, -3.6 [-3.9--2.4] cm H2O and -2.1 [-2.5--1.1] cm H2O, respectively, p < 0.001 for both comparisons; PTPmin of 155 [118-209] cm H2O s/min, 197 [145-269] cm H2O s/min, and 134 [93-169] cm H2O s/min, respectively, p < 0.001 for both comparisons). Pendelluft magnitude was higher in NAVA (12 ± 7%) and PAV + (13 ± 7%) compared with PSV (8 ± 6%), p < 0.001. Pendelluft magnitude was strongly associated with respiratory drive (ß = -2.771, p-value < 0.001) and inspiratory effort (ß = 0.026, p < 0.001), independent of the ventilatory mode. A higher magnitude of pendelluft in proportional modes compared with PSV existed after adjusting for PTPmin (ß = 2.606, p = 0.010 for NAVA, and ß = 3.360, p = 0.004 for PAV +), and only for PAV + when adjusted for respiratory drive (ß = 2.643, p = 0.009 for PAV +). CONCLUSIONS: Pendelluft magnitude is associated with respiratory drive and inspiratory effort. Proportional modes do not prevent its occurrence in resolving ARDS compared with PSV.

Mortality in patients with severe COVID-19 who underwent tracheostomy due to prolonged mechanical ventilation / Mortalidad en pacientes con COVID-19 grave sometidos a traqueostomía por ventilación mecánica prolongada

BACKGROUND: The usefulness of tracheostomy has been questioned in patients with COVID-19 and prolonged invasive mechanical ventilation (IMV). AIM: To compare the 90-day mortality rate of patients who underwent a tracheostomy due prolonged IMV with those that did not receive this procedure. MATERIAL AND METHODS: We studied a historical cohort of 92 patients with COVID-19 and prolonged IMV (> 10 days). The primary outcome was the 90-day mortality rate. Secondary outcomes included days on IMV, hospital/intensive care unit (ICU) length of stay, frequency of nosocomial infections, and thrombotic complications demonstrated by images. A logistic regression was performed to adjust the effect of tracheostomy by SOFA score and days on IMV. RESULTS: Forty six patients aged 54 to 66 years (72% males) underwent tracheostomy. They had a median of two comorbidities, and received the procedure after a median of 20.5 days on IMV (interquartile range: 17-26). 90-day mortality was lower in patients who were tracheostomized than in the control group (6.5% vs. 32.6%, p-value < 0.01). However, after controlling for confounding factors, no differences were found in mortality between both groups (relative risk = 0.303, p-value = 0.233). Healthcare-associated infections and hospital/ICU length of stay were higher in patients with tracheostomy than in controls. Thrombotic complications occurred in 42.4% of the patients, without differences between both groups. No cases of COVID-19 were registered in the healthcare personnel who performed tracheostomies. CONCLUSIONS: In patients with COVID-19 undergoing prolonged IMV, performing a tracheostomy is not associated with excess mortality, and it is a safe procedure for healthcare personnel.

ANTECEDENTES: La utilidad de la traqueostomía en pacientes COVID-19 sometidos a ventilación mecánica invasiva (VMI) prolongada ha sido cuestionada. OBJETIVO: Comparar la mortalidad a 90 días en estos pacientes, con y sin traqueostomía. MATERIAL Y MÉTODOS: Estudiamos una cohorte histórica de 92 pacientes COVID-19 con VMI prolongada (>10 días). El desenlace prima-rio fue mortalidad a 90 días. Se consideraron desenlaces secundarios los días en VMI, estadía hospitalaria/UCI, frecuencia de infecciones nosocomiales, y eventos trombóticos. Mediante regresión logística se ajustó el efecto de la traqueostomía en la mortalidad, por SOFA y días de VMI. RESULTADOS: Cuarenta y seis pacientes de 54 a 66 años (72% hombres) fueron traqueostomizados. Ellos tenían una mediana de dos comorbilidades, y recibieron el procedimiento luego de una mediana de 20,5 días en VMI (rango intercuartílico: 17-26). En el análisis crudo, la mortalidad a 90 días fue menor en los pacientes con traqueostomía que en el grupo control (6,5% vs. 32,6%; p < 0,001). No obstante, luego de controlar por factores de confusión, no se encontraron diferencias en mortalidad (riesgo relativo 0,303; p = 0,233). Las infecciones asociadas a la atención de salud y la estadía en hospital/UCI fueron mayores en los pacientes traqueostomizados que en los controles. Los eventos trombóticos ocurrieron en el 42,4% de los pacientes, sin diferencias entre grupos. No hubo casos de COVID-19 en el personal de salud que realizó las traqueostomías. CONCLUSIONES: En pacientes con COVID-19 sometidos a VMI prolongada, la realización de una traqueostomía no se asocia a un exceso de mortalidad, y es un procedimiento seguro para el personal sanitario.

Mortality in patients with severe COVID-19 who underwent tracheostomy due to prolonged mechanical ventilation.

BACKGROUND: The usefulness of tracheostomy has been questioned in patients with COVID-19 and prolonged invasive mechanical ventilation (IMV). AIM: To compare the 90-day mortality rate of patients who underwent a tracheostomy due prolonged IMV with those that did not receive this procedure. MATERIAL AND METHODS: We studied a historical cohort of 92 patients with COVID-19 and prolonged IMV (> 10 days). The primary outcome was the 90-day mortality rate. Secondary outcomes included days on IMV, hospital/intensive care unit (ICU) length of stay, frequency of nosocomial infections, and thrombotic complications demonstrated by images. A logistic regression was performed to adjust the effect of tracheostomy by SOFA score and days on IMV. RESULTS: Forty six patients aged 54 to 66 years (72% males) underwent tracheostomy. They had a median of two comorbidities, and received the procedure after a median of 20.5 days on IMV (interquartile range: 17-26). 90-day mortality was lower in patients who were tracheostomized than in the control group (6.5% vs. 32.6%, p-value < 0.01). However, after controlling for confounding factors, no differences were found in mortality between both groups (relative risk = 0.303, p-value = 0.233). Healthcare-associated infections and hospital/ICU length of stay were higher in patients with tracheostomy than in controls. Thrombotic complications occurred in 42.4% of the patients, without differences between both groups. No cases of COVID-19 were registered in the healthcare personnel who performed tracheostomies. CONCLUSIONS: In patients with COVID-19 undergoing prolonged IMV, performing a tracheostomy is not associated with excess mortality, and it is a safe procedure for healthcare personnel.

Inflammatory biomarkers and pendelluft magnitude in ards patients transitioning from controlled to partial support ventilation.

The transition from controlled to partial support ventilation is a challenge in acute respiratory distress syndrome (ARDS) patients due to the risks of patient-self-inflicted lung injury. The magnitude of tidal volume (VT) and intrapulmonary dyssynchrony (pendelluft) are suggested mechanisms of lung injury. We conducted a prospective, observational, physiological study in a tertiary academic intensive care unit. ARDS patients transitioning from controlled to partial support ventilation were included. On these, we evaluated the association between changes in inflammatory biomarkers and esophageal pressure swing (ΔPes), transpulmonary driving pressure (ΔPL), VT, and pendelluft. Pendelluft was defined as the percentage of the tidal volume that moves from the non-dependent to the dependent lung region during inspiration, and its frequency at different thresholds (- 15, - 20 and - 25%) was also registered. Blood concentrations of inflammatory biomarkers (IL-6, IL-8, TNF-α, ANGPT2, RAGE, IL-18, Caspase-1) were measured before (T0) and after 4-h (T4) of partial support ventilation. Pendelluft, ΔPes, ΔPL and VT were recorded. Nine out of twenty-four patients (37.5%) showed a pendelluft mean ≥ 10%. The mean values of ΔPes, ΔPL, and VT were - 8.4 [- 6.7; - 10.2] cmH2O, 15.2 [12.3-16.5] cmH2O and 8.1 [7.3-8.9] m/kg PBW, respectively. Significant associations were observed between the frequency of high-magnitude pendelluft and IL-8, IL-18, and Caspase-1 changes (T0/T4 ratio). These results suggest that the frequency of high magnitude pendelluft may be a potential determinant of inflammatory response related to inspiratory efforts in ARDS patients transitioning to partial support ventilation. Future studies are needed to confirm these results.

Estimation of changes in cyclic lung strain by electrical impedance tomography: Proof-of-concept study.

RATIONALE: Cyclic strain may be a determinant of ventilator-induced lung injury. The standard for strain assessment is the computed tomography (CT), which does not allow continuous monitoring and exposes to radiation. Electrical impedance tomography (EIT) is able to monitor changes in regional lung ventilation. In addition, there is a correlation between mechanical deformation of materials and detectable changes in its electrical impedance, making EIT a potential surrogate for cyclic lung strain measured by CT (StrainCT ). OBJECTIVES: To compare the global StrainCT with the change in electrical impedance (ΔZ). METHODS: Acute respiratory distress syndrome patients under mechanical ventilation (VT 6 mL/kg ideal body weight with positive end-expiratory pressure 5 [PEEP 5] and best PEEP according to EIT) underwent whole-lung CT at end-inspiration and end-expiration. Biomechanical analysis was used to construct 3D maps and determine StrainCT at different levels of PEEP. CT and EIT acquisitions were performed simultaneously. Multilevel analysis was employed to determine the causal association between StrainCT and ΔZ. Linear regression models were used to predict the change in lung StrainCT between different PEEP levels based on the change in ΔZ. MAIN RESULTS: StrainCT was positively and independently associated with ΔZ at global level (P < .01). Furthermore, the change in StrainCT (between PEEP 5 and Best PEEP) was accurately predicted by the change in ΔZ (R2 0.855, P < .001 at global level) with a high agreement between predicted and measured StrainCT . CONCLUSIONS: The change in electrical impedance may provide a noninvasive assessment of global cyclic strain, without radiation at bedside.

Experiencia de reconversión de un servicio clínico anestésico-quirúrgico en unidad de pacientes críticos COVID-19 en un hospital universitario / Experience of transforming a clinical surgical-anesthetic unit into a COVID-19 critical patient one in a teaching hospital

INTRODUCTION: The experience of restructuring a clinical surgical-anesthetic unit into a critical patient unit in charge of surgical- anesthetic personnel is presented during the period from May to July 2020 in the context of a SARS-CoV-2 pandemic. OBJECTIVES: Describe the unit's restructuring process, considering technical aspects, changes in staff functions, clinical outcomes of the patients, quality indicators obtained and the psychological impact on the healthcare team. MATHERIAL AND METHODS: The strategies implemented by the responsible experts were described (ie: engineering). Clinical data were obtained from an insti- tutional database and electronical medical records. The management of human resources was described using administrative records of the services of anesthesiology, OR and critical patient unit. The psychological impact on the unit staff was evaluated by applying the Maslach questionnaire. The quality of the clinical management of the unit was obtained from the compilation of standardized quality indicators for the critical patient units of the institution. RESULTS: 25 patients were admitted in the unit. The mean age was 62 ± 12 years. About the complications, 52% had pulmonary embolism, 36% had acute kidney injury, and 1 patient died. The prevalence of Burnout Syndrome was 73.6%. The occurrence of adverse events was minimal. DISCUSSION: The transformation of an anesthetic-surgical unit into a COVID critical patient one, demands a complex net of coordinated strategies to allow facing the attention demand with positive clinical results, at the expense of the health care team mental health.

INTRODUCCIÓN: Se presenta la experiencia de reconversión de una unidad de cuidados posanestésicos a una unidad de cuidados intensivos a cargo de personal anestésico-quirúrgico entre mayo y julio de 2020, en contexto de pandemia por SARS-CoV-2. OBJETIVOS: Describir el proceso de reconversión considerando aspectos técnicos, pertinentes al recurso humano, resultados clínicos, indicadores de calidad e impacto psicológico en el equipo de salud. MATERIALES Y MÉTODOS: Se describen las estrategias implementadas por los expertos responsables. Se obtienen datos clínicos desde base de datos institucional y ficha clínica electrónica. Se describe la gestión del recurso humano utilizando registros administrativos de los servicios involucrados. El impacto psicológico en el personal fue evaluado aplicando el cuestionario de Maslach. La calidad de la gestión clínica se obtiene a partir de indicadores de calidad estandarizados para las unidades de pacientes críticos de nuestro establecimiento. RESULTADOS: Se atendieron 25 pacientes en la unidad. La edad promedio fue 62 ± 12 años. El 52% presentó tromboembolismo pulmonar, 36% injuria renal aguda como complicación. Un paciente falleció. La prevalencia de síndrome de Burnout fue de 73,6%. La ocurrencia de eventos adversos fue baja. CONCLUSIONESConclusiones: La reconversión de una unidad anestésico-quirúrgica a una unidad crítica COVID-19, demanda un complejo entramado de estrategias coordinadas que permiten responder a la demanda de atención con resultados clínicos positivos, a expensas del costo de la salud mental del equipo de salud involucrado.

Fiber optic bronchoscopy-assisted percutaneous tracheostomy: a decade of experience at a university hospital.

OBJECTIVE: To evaluate the efficacy and safety of percutaneous tracheostomy by means of single-step dilation with fiber optic bronchoscopy assistance in critical care patients under mechanical ventilation. METHODS: Between the years 2004 and 2014, 512 patients with indication of tracheostomy according to clinical criteria, were prospectively and consecutively included in our study. One-third of them were high-risk patients. Demographic variables, APACHE II score, and days on mechanical ventilation prior to percutaneous tracheostomy were recorded. The efficacy of the procedure was evaluated according to an execution success rate and based on the necessity of switching to an open surgical technique. Safety was evaluated according to post-operative and operative complication rates. RESULTS: The mean age of the group was 64 ± 18 years (203 women and 309 males). The mean APACHE II score was 21 ± 3. Patients remained an average of 11 ± 3 days on mechanical ventilation before percutaneous tracheostomy was performed. All procedures were successfully completed without the need to switch to an open surgical technique. Eighteen patients (3.5%) presented procedure complications. Five patients experienced transient desaturation, 4 presented low blood pressure related to sedation, and 9 presented minor bleeding, but none required a transfusion. No serious complications or deaths associated with the procedure were recorded. Eleven patients (2.1%) presented post-operative complications. Seven presented minor and transitory bleeding of the percutaneous tracheostomy stoma, 2 suffered displacement of the tracheostomy cannula, and 2 developed a superficial infection of the stoma. CONCLUSION: Percutaneous tracheostomy using the single-step dilation technique with fiber optic bronchoscopy assistance seems to be effective and safe in critically ill patients under mechanical ventilation when performed by experienced intensive care specialists using a standardized procedure.

Traqueostomía percutánea con asistencia fibrobroncoscópica: una década de experiencia en un hospital universitario / Fiber optic bronchoscopy-assisted percutaneous tracheostomy: a decade of experience at a university hospital

RESUMEN Objetivo: Evaluar eficacia y seguridad de la traqueostomía percutánea, mediante dilatación única con asistencia fibrobroncoscópica, en pacientes críticos sometidos a ventilación mecánica. Métodos: Entre los años 2004 y 2014, se incluyeron prospectivamente 512 enfermos consecutivos con indicación de traqueostomía según los criterios clínicos de nuestro centro. Un tercio de los pacientes fueron de alto riesgo. Se registraron variables demográficas, puntaje APACHE II, y días de ventilación mecánica previo a traqueostomía percutánea. La eficacia del procedimiento fue evaluada mediante tasa de éxito en su ejecución y necesidad de conversión a técnica abierta. La seguridad fue evaluada por tasa de complicaciones operatorias y postoperatorias. Resultados: La edad media del grupo fue 64 ± 18 años (203 mujeres y 309 varones). El puntaje APACHE II fue 21 ± 3. Los pacientes permanecieron en promedio 11 ± 3 días en ventilación mecánica antes de la realización de la traqueostomía percutánea. Todos los procedimientos se completaron exitosamente, sin necesidad de convertir a técnica abierta. Dieciocho pacientes (3,5%) presentaron complicaciones operatorias. Cinco pacientes experimentaron desaturación transitoria, cuatro presentaron hipotensión relacionada a la sedación, y nueve presentaron sangrado menor, pero ninguno requirió transfusión. No se registraron complicaciones graves, ni muertes asociadas al procedimiento. Once pacientes (2,1%) presentaron complicaciones postoperatorias. Siete presentaron sangrado menor y transitorio del estoma de la traqueostomía percutánea, 2 sufrieron desplazamiento de la cánula de traqueostomía y 2 desarrollaron infección superficial del estoma. Conclusión: La traqueostomía percutánea mediante la técnica de dilatación única con asistencia fibrobroncoscópica, parece ser efectiva y segura en enfermos críticos sometidos a ventilación mecánica, cuando es realizada por intensivistas experimentados mediante un abordaje ...

ABSTRACT Objective: To evaluate the efficacy and safety of percutaneous tracheostomy by means of single-step dilation with fiber optic bronchoscopy assistance in critical care patients under mechanical ventilation. Methods: Between the years 2004 and 2014, 512 patients with indication of tracheostomy according to clinical criteria, were prospectively and consecutively included in our study. One-third of them were high-risk patients. Demographic variables, APACHE II score, and days on mechanical ventilation prior to percutaneous tracheostomy were recorded. The efficacy of the procedure was evaluated according to an execution success rate and based on the necessity of switching to an open surgical technique. Safety was evaluated according to post-operative and operative complication rates. Results: The mean age of the group was 64 ± 18 years (203 women and 309 males). The mean APACHE II score was 21 ± 3. Patients remained an average of 11 ± 3 days on mechanical ventilation before percutaneous tracheostomy was performed. All procedures were successfully completed without the need to switch to an open surgical technique. Eighteen patients (3.5%) presented procedure complications. Five patients experienced transient desaturation, 4 presented low blood pressure related to sedation, and 9 presented minor bleeding, but none required a transfusion. No serious complications or deaths associated with the procedure were recorded. Eleven patients (2.1%) presented post-operative complications. Seven presented minor and transitory bleeding of the percutaneous tracheostomy stoma, 2 suffered displacement of the tracheostomy cannula, and 2 developed a superficial infection of the stoma. Conclusion: Percutaneous tracheostomy using the single-step dilation technique with fiber optic bronchoscopy assistance seems to be effective and safe in critically ill patients under mechanical ventilation when performed by experienced intensive care specialists using ...

Falla hepática fulminante por virus hepatitis B en paciente coinfectado por VIH: un desafío terapéutico. Caso clínico / Fulminant hepatic failure by hepatitis B virus in a patient with human immunodeficiency virus infection: Report of one case

The human immunodeficiency virus (HIV) and hepatitis B virus (HBV) co-infection is a common problem in the world, with an estimated prevalence of up to 8 percent. We report a 27-year-old man admitted to the intensive care unit with an acute liver failure by HBV. During hospital stay, a co-infection with HIV virus was detected. Treatment with early antiviral therapy was started with emtricitabine, tenofovir and raltegravir, to cover both HBV and HIV. Despite therapy, the patient died two weeks after admission.

[Fulminant hepatic failure by hepatitis B virus in a patient with human immunodeficiency virus infection: report of one case]. / Falla hepática fulminante por virus hepatitis B en paciente coinfectado por VIH: un desafío terapéutico. Caso clínico.

The human immunodeficiency virus (HIV) and hepatitis B virus (HBV) co-infection is a common problem in the world, with an estimated prevalence of up to 8%. We report a 27-year-old man admitted to the intensive care unit with an acute liver failure by HBV. During hospital stay, a co-infection with HIV virus was detected. Treatment with early antiviral therapy was started with emtricitabine, tenofovir and raltegravir, to cover both HBV and HIV. Despite therapy, the patient died two weeks after admission.