Shortening ventilatory support with a protocol based on daily extubation screening and noninvasive ventilation in selected patients

BACKGROUND: Prolonged invasive mechanical ventilation and reintubation are associated with adverse outcomes and increased mortality. Daily screening to identify patients able to breathe without support is recommended to reduce the length of mechanical ventilation. Noninvasive positive-pressure ventilation has been proposed as a technique to shorten the time that patients remain on invasive ventilation. METHODS: We conducted a before-and-after study to evaluate the efficacy of an intervention that combined daily screening with the use of noninvasive ventilation immediately after extubation in selected patients. The population consisted of patients who had been intubated for at least 2 days. RESULTS: The baseline characteristics were similar between the groups. The intervention group had a lower length of invasive ventilation (6 [4;9] vs. 7 [4;11.5] days, p = 0.04) and total (invasive plus noninvasive) ventilator support (7 [4;11] vs. 9 [6;8], p = 0.01). Similar reintubation rates within 72 hours were observed for both groups. In addition, a lower ICU mortality was found in the intervention group (10.8% vs. 24.3%, p = 0.03), with a higher cumulative survival probability at 60 days (p = 0.05). Multivariate analysis showed that the intervention was an independent factor associated with survival (RR: 2.77; CI 1.14-6.65; p = 0.03), whereas the opposite was found for reintubation at 72 hours (RR: 0.27; CI 0.11-0.65; p = 0.01). CONCLUSION: The intervention reduced the length of invasive ventilation and total ventilatory support without increasing the risk of reintubation and was identified as an independent factor associated with survival

Factors associated with variation in intracranial pressure in a model of intra-abdominal hypertension with acute lung injury

OBJETIVO: Avaliar o efeito de alterações hemodinâmicas, respiratórias e metabólicas sobre a pressão intracraniana em um modelo de lesão pulmonar aguda e síndrome compartimental abdominal. MÉTODOS: Oito porcos Agroceres foram submetidos, após a instrumentação, a cinco cenários clínicos: 1) estado basal com baixa pressão intra-abdominal e pulmão sadio; 2) pneumoperitôneo, com pressão intra-abdominal de 20 mm Hg; 3) lesão pulmonar aguda induzida por lavagem pulmonar e desativação de surfactante; 4) pneumoperitôneo com pressão intra-abdominal de 20 mm Hg na vigência de lesão pulmonar aguda e com PEEP baixo; e 5) PEEP ajustado a 27 cm H2O na vigência de pneumoperitôneo e lesão pulmonar aguda. Variáveis respiratórias e hemodinâmicas foram coletadas. Análise multivariada foi realizada buscando as variáveis associadas com elevação da pressão intracraniana nos cinco cenários estudados. RESULTADOS: Após a análise multivariada, nas situações não associadas com lesão pulmonar aguda apenas a pressão de platô das vias aéreas se correlacionou positivamente com a pressão intracraniana. Nos modelos associados com lesão pulmonar aguda, a pressão de platô de vias aéreas, a pressão arterial de CO2, o CO2 no final da expiração e a pressão venosa central se correlacionaram positivamente com incrementos da pressão intracraniana. CONCLUSÃO: Em um modelo de disfunção orgânica múltipla com situações clínicas associadas com aumento da pressão torácica e abdominal, o incremento da pressão intracraniana desencadeado pela elevação da pressão abdominal parece ser decorrente da piora da complacência do sistema respiratório e da redução do gradiente para drenagem venosa cerebral ocasionado pela elevação da pressão venosa central.OBJECTIVE: To evaluate the effects of hemodynamic, respiratory and metabolic changes on intracranial pressure in a model of acute lung injury and abdominal compartment syndrome. METHODS: Eight Agroceres pigs were submitted to five different clinical scenarios after instrumentation: 1) a baseline condition with low intra-abdominal pressure and healthy lungs; 2) pneumoperitoneum with 20 mmHg intra-abdominal pressure; 3) acute lung injury induced by pulmonary lavage with surfactant deactivation; 4) pneumoperitoneum with 20 mmHg intra-abdominal pressure with lung pulmonary injury and low positive end-expiratory pressure; and 5) 27 cmH2O positive end-expiratory pressure with pneumoperitoneum and acute lung injury. Respiratory and hemodynamic variables were collected. A multivariate analysis was conducted to search for variables associated with increased intracranial pressure in the five scenarios. RESULTS: Only plateau airway pressure showed a positive correlation with intracranial pressure in the multivariate analysis. In the models with acute lung injury, plateau airway pressure, CO2 arterial pressure, end tidal CO2 and central venous pressure were positively correlated with increased intracranial pressure. CONCLUSION: In a model of multiple organ dysfunction with associated clinical conditions causing increased intra-thoracic and abdominal pressure, increased intracranial pressure triggered by elevated intra-abdominal pressure is apparently caused by worsened respiratory system compliance and a reduced brain venous drainage gradient due to increased central venous pressure

Late recognition and illness severity are determinants of early death in severe septic patients

OBJECTIVE: To identify the independent variables associated with death within 4 days after the first sepsis-induced organ dysfunction. METHODS: In this prospective observational study, severe sepsis and septic shock patients were classified into 3 groups: Group 1, survivors; Group 2, late non-survivors; and Group 3, early non-survivors. Early death was defined as death occurring within 4 days after the first sepsis-induced organ dysfunction. Demographic, clinical and laboratory data were collected and submitted to univariate and multinomial analyses. RESULTS: The study included 414 patients: 218 (52.7%) in Group 1, 165 (39.8%) in Group 2, and 31 (7.5%) in Group 3. A multinomial logistic regression analysis showed that age, Acute Physiology and Chronic Health Evaluation II score, Sepsis-related Organ Failure Assessment score after the first 24 hours, nosocomial infection, hepatic dysfunction, and the time elapsed between the onset of organ dysfunction and the sepsis diagnosis were associated with early mortality. In contrast, Black race and a source of infection other than the urinary tract were associated with late death. Among the non-survivors, early death was associated with Acute Physiology and Chronic Health Evaluation II score, chronic renal failure, hepatic dysfunction Sepsis-related Organ Failure Assessment score after 24 hours, and the duration of organ dysfunction. CONCLUSION: Factors related to patients' intrinsic characteristics and disease severity as well as the promptness of sepsis recognition are associated with early death among severe septic patients.Fundacao de Amparo a Pesquisa do Estado de Sao PauloFederal University of São Paulo Department of Anesthesiology Pain and Critical CareLatin American Sepsis InstituteFederal University of São Paulo Department of Infectious DiseasesSírio Libanês Hospital Intensive Care UnitHospital Israelita Albert Einstein Intensive Care UnitUNIFESP, Department of Anesthesiology Pain and Critical CareUNIFESP, Department of Infectious DiseasesSciEL

Late recognition and illness severity are determinants of early death in severe septic patients

OBJECTIVE: To identify the independent variables associated with death within 4 days after the first sepsis-induced organ dysfunction. METHODS: In this prospective observational study, severe sepsis and septic shock patients were classified into 3 groups: Group 1, survivors; Group 2, late non-survivors; and Group 3, early non-survivors. Early death was defined as death occurring within 4 days after the first sepsis-induced organ dysfunction. Demographic, clinical and laboratory data were collected and submitted to univariate and multinomial analyses. RESULTS: The study included 414 patients: 218 (52.7%) in Group 1, 165 (39.8%) in Group 2, and 31 (7.5%) in Group 3. A multinomial logistic regression analysis showed that age, Acute Physiology and Chronic Health Evaluation II score, Sepsis-related Organ Failure Assessment score after the first 24 hours, nosocomial infection, hepatic dysfunction, and the time elapsed between the onset of organ dysfunction and the sepsis diagnosis were associated with early mortality. In contrast, Black race and a source of infection other than the urinary tract were associated with late death. Among the non-survivors, early death was associated with Acute Physiology and Chronic Health Evaluation II score, chronic renal failure, hepatic dysfunction Sepsis-related Organ Failure Assessment score after 24 hours, and the duration of organ dysfunction. CONCLUSION: Factors related to patients' intrinsic characteristics and disease severity as well as the promptness of sepsis recognition are associated with early death among severe septic patients

Severe hypoxemia during veno-venous extracorporeal membrane oxygenation: exploring the limits of extracorporeal respiratory support

OBJECTIVE: Veno-venous extracorporeal oxygenation for respiratory support has emerged as a rescue alternative for patients with hypoxemia. However, in some patients with more severe lung injury, extracorporeal support fails to restore arterial oxygenation. Based on four clinical vignettes, the aims of this article were to describe the pathophysiology of this concerning problem and to discuss possibilities for hypoxemia resolution. METHODS: Considering the main reasons and rationale for hypoxemia during veno-venous extracorporeal membrane oxygenation, some possible bedside solutions must be considered: 1) optimization of extracorporeal membrane oxygenation blood flow; 2) identification of recirculation and cannula repositioning if necessary; 3) optimization of residual lung function and consideration of blood transfusion; 4) diagnosis of oxygenator dysfunction and consideration of its replacement; and finally 5) optimization of the ratio of extracorporeal membrane oxygenation blood flow to cardiac output, based on the reduction of cardiac output. CONCLUSION: Therefore, based on the pathophysiology of hypoxemia during veno-venous extracorporeal oxygenation support, we propose a stepwise approach to help guide specific interventions