Lung Ultrasound in Emergency and Critically Ill Patients: Number of Supervised Exams to Reach Basic Competence.

BACKGROUND: Lung ultrasound is increasingly used in critically ill patients as an alternative to bedside chest radiography, but the best training method remains uncertain. This study describes a training curriculum allowing trainees to acquire basic competence. METHODS: This multicenter, prospective, and educational study was conducted in 10 Intensive Care Units in Brazil, China, France and Uruguay. One hundred residents, respiratory therapists, and critical care physicians without expertise in transthoracic ultrasound (trainees) were trained by 18 experts. The main study objective was to determine the number of supervised exams required to get the basic competence, defined as the trainees' ability to adequately classify lung regions with normal aeration, interstitial-alveolar syndrome, and lung consolidation. An initial 2-h video lecture provided the rationale for image formation and described the ultrasound patterns commonly observed in critically ill and emergency patients. Each trainee performed 25 bedside ultrasound examinations supervised by an expert. The progression in competence was assessed every five supervised examinations. In a new patient, 12 pulmonary regions were independently classified by the trainee and the expert. RESULTS: Progression in competence was derived from the analysis of 7,330 lung regions in 2,562 critically ill and emergency patients. After 25 supervised examinations, 80% of lung regions were adequately classified by trainees. The ultrasound examination mean duration was 8 to 10 min in experts and decreased from 19 to 12 min in trainees (after 5 vs. 25 supervised examinations). The median training duration was 52 (42, 82) days. CONCLUSIONS: A training curriculum including 25 transthoracic ultrasound examinations supervised by an expert provides the basic skills for diagnosing normal lung aeration, interstitial-alveolar syndrome, and consolidation in emergency and critically ill patients.

Prediction of Early TBI Mortality Using a Machine Learning Approach in a LMIC Population.

Background: In a time when the incidence of severe traumatic brain injury (TBI) is increasing in low- to middle-income countries (LMICs), it is important to understand the behavior of predictive variables in an LMIC's population. There are few previous attempts to generate prediction models for TBI outcomes from local data in LMICs. Our study aim is to design and compare a series of predictive models for mortality on a new cohort in TBI patients in Brazil using Machine Learning. Methods: A prospective registry was set in São Paulo, Brazil, enrolling all patients with a diagnosis of TBI that require admission to the intensive care unit. We evaluated the following predictors: gender, age, pupil reactivity at admission, Glasgow Coma Scale (GCS), presence of hypoxia and hypotension, computed tomography findings, trauma severity score, and laboratory results. Results: Overall mortality at 14 days was 22.8%. Models had a high prediction performance, with the best prediction for overall mortality achieved through Naive Bayes (area under the curve = 0.906). The most significant predictors were the GCS at admission and prehospital GCS, age, and pupil reaction. When predicting the length of stay at the intensive care unit, the Conditional Inference Tree model had the best performance (root mean square error = 1.011), with the most important variable across all models being the GCS at scene. Conclusions: Models for early mortality and hospital length of stay using Machine Learning can achieve high performance when based on registry data even in LMICs. These models have the potential to inform treatment decisions and counsel family members. Level of evidence: This observational study provides a level IV evidence on prognosis after TBI.

Mensuração da pressão intracraniana e desfechos em curto prazo de pacientes com lesão encefálica traumática: uma análise de propensão pareada / Measurement of intracranial pressure and short-term outcomes of patients with traumatic brain injury: a propensity-matched analysis

RESUMO Objetivo: Avaliar o impacto do monitoramento da pressão intracraniana nos desfechos em curto prazo de pacientes com lesão encefálica traumática. Métodos: Estudo retrospectivo e observacional que incluiu 299 pacientes consecutivos admitidos por lesão cerebral traumática entre janeiro de 2011 e julho de 2012 em um centro de trauma Nível 1 localizado em São Paulo (SP). Os pacientes foram categorizados em dois grupos, segundo a mensuração da pressão intracraniana (grupos com mensuração da pressão intracraniana e sem mensuração da pressão intracraniana). Aplicamos uma análise de propensão pareada para ajustar quanto a possíveis fatores de confusão (variáveis contidas no algoritmo prognóstico CRASH Score). Resultados: A mortalidade global aos 14 dias (16%) foi equivalente à observada em países desenvolvidos no estudo CRASH, e melhor que o previsto com base na calculadora de escore CRASH (20,6%), com uma proporção padronizada de mortalidade de 0,77. No total, 28 pacientes receberam monitoramento da pressão intracraniana (grupo com mensuração da pressão intracraniana), dos quais 26 foram pareados em proporção 1:1 com pacientes do grupo sem mensuração da pressão intracraniana. Não houve melhora no grupo com mensuração da pressão intracraniana em comparação àquele sem mensuração da pressão intracraniana quanto à mortalidade hospitalar, à mortalidade aos 14 dias, ou à mortalidade combinada hospitalar e em hospital de retaguarda. A sobrevivência até 14 dias foi também similar entre os grupos. Conclusão: Os pacientes que receberam monitoramento da pressão intracraniana tendem a ser portadores de lesões encefálicas mais graves. Porém, após ajustar quanto a múltiplos fatores de confusão com a utilização de um escore de propensão, não se observou qualquer benefício em termos de sobrevivência entre os pacientes com monitoramento da pressão intracraniana em relação aos tradados segundo um protocolo clínico sistematizado.

ABSTRACT Objective: To assess the impact of intracranial pressure monitoring on the short-term outcomes of traumatic brain injury patients. Methods: Retrospective observational study including 299 consecutive patients admitted due to traumatic brain injury from January 2011 through July 2012 at a Level 1 trauma center in São Paulo, Brazil. Patients were categorized in two groups according to the measurement of intracranial pressure (measured intracranial pressure and non-measured intracranial pressure groups). We applied a propensity-matched analysis to adjust for possible confounders (variables contained in the Crash Score prognostic algorithm). Results: Global mortality at 14 days (16%) was equal to that observed in high-income countries in the CRASH Study and was better than expected based on the CRASH calculator score (20.6%), with a standardized mortality ratio of 0.77. A total of 28 patients received intracranial pressure monitoring (measured intracranial pressure group), of whom 26 were paired in a 1:1 fashion with patients from the non-measured intracranial pressure group. There was no improvement in the measured intracranial pressure group compared to the non-measured intracranial pressure group regarding hospital mortality, 14-day mortality, or combined hospital and chronic care facility mortality. Survival up to 14 days was also similar between groups. Conclusion: Patients receiving intracranial pressure monitoring tend to have more severe traumatic brain injuries. However, after adjusting for multiple confounders using propensity scoring, no benefits in terms of survival were observed among intracranial pressure-monitored patients and those managed with a systematic clinical protocol.

Measurement of intracranial pressure and short-term outcomes of patients with traumatic brain injury: a propensity-matched analysis.

OBJECTIVE: To assess the impact of intracranial pressure monitoring on the short-term outcomes of traumatic brain injury patients. METHODS: Retrospective observational study including 299 consecutive patients admitted due to traumatic brain injury from January 2011 through July 2012 at a Level 1 trauma center in São Paulo, Brazil. Patients were categorized in two groups according to the measurement of intracranial pressure (measured intracranial pressure and non-measured intracranial pressure groups). We applied a propensity-matched analysis to adjust for possible confounders (variables contained in the Crash Score prognostic algorithm). RESULTS: Global mortality at 14 days (16%) was equal to that observed in high-income countries in the CRASH Study and was better than expected based on the CRASH calculator score (20.6%), with a standardized mortality ratio of 0.77. A total of 28 patients received intracranial pressure monitoring (measured intracranial pressure group), of whom 26 were paired in a 1:1 fashion with patients from the non-measured intracranial pressure group. There was no improvement in the measured intracranial pressure group compared to the non-measured intracranial pressure group regarding hospital mortality, 14-day mortality, or combined hospital and chronic care facility mortality. Survival up to 14 days was also similar between groups. CONCLUSION: Patients receiving intracranial pressure monitoring tend to have more severe traumatic brain injuries. However, after adjusting for multiple confounders using propensity scoring, no benefits in terms of survival were observed among intracranial pressure-monitored patients and those managed with a systematic clinical protocol.

Brazilian recommendations of mechanical ventilation 2013. Part 2.

Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumologia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document.

Recomendações brasileiras de ventilação mecânica 2013. Parte 2 / Brazilian recommendations of mechanical ventilation 2013. Part 2

O suporte ventilatório artificial invasivo e não invasivo ao paciente grave tem evoluído e inúmeras evidências têm surgido, podendo ter impacto na melhora da sobrevida e da qualidade do atendimento oferecido nas unidades de terapia intensiva no Brasil. Isto posto, a Associação de Medicina Intensiva Brasileira (AMIB) e a Sociedade Brasileira de Pneumologia e Tisiologia (SBPT) - representadas por seu Comitê de Ventilação Mecânica e sua Comissão de Terapia Intensiva, respectivamente, decidiram revisar a literatura e preparar recomendações sobre ventilação mecânica, objetivando oferecer aos associados um documento orientador das melhores práticas da ventilação mecânica na beira do leito, com base nas evidências existentes, sobre os 29 subtemas selecionados como mais relevantes no assunto. O projeto envolveu etapas que visaram distribuir os subtemas relevantes ao assunto entre experts indicados por ambas as sociedades, que tivessem publicações recentes no assunto e/ou atividades relevantes em ensino e pesquisa no Brasil, na área de ventilação mecânica. Esses profissionais, divididos por subtemas em duplas, responsabilizaram-se por fazer uma extensa revisão da literatura mundial. Reuniram-se todos no Fórum de Ventilação Mecânica, na sede da AMIB, na cidade de São Paulo (SP), em 3 e 4 de agosto de 2013, para finalização conjunta do texto de cada subtema e apresentação, apreciação, discussão e aprovação em plenária pelos 58 participantes, permitindo a elaboração de um documento final.

Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumologia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document.

Efeitos da posição sentada na força de músculos respiratórios durante o desmame de pacientes sob ventilação mecânica prolongada no pós-operatório de cirurgia cardiovascular / Effects of sitting position on the strength of respiratory muscles during weaning of patients under prolonged mechanical ventilation in the postoperative period of cardiovascular surgery

O objetivo do estudo foi investigar os efeitos da posição sentada, nos parâmetros ventilatórios e hemodinâmicos, em pacientes com suporte ventilatório mecânico prolongado, estáveis hemodinamicamente. Participaram do estudo 40 pacientes que foram randomizados em grupo controle (n=17) e grupo intervenção (n=23). Foram mensurados parâmetros hemodinâmicos, gasometria arterial, força muscular respiratória e ventilometria, realizados em dois momentos: primeira e segunda avaliação, com intervalo de 30 minutos entre as medidas. No grupo controle, as duas avaliações foram realizadas no leito, com a cabeceira elevada a 30°. No grupo intervenção, a primeira avaliação foi realizada no leito (30°) e a segunda, 30 minutos após transferência para a poltrona, na posição sentada (90°). A idade média da amostra foi de 64,7±11,2 anos. O resultado do estudo demonstrou que não houve diferenças em relação às variáveis, hemodinâmicas, gasométricas, capacidade vital forçada, volume minuto e volume de ar corrente. Entretanto, ocorreu aumento significativo da pressão inspiratória máxima (PImáx) no grupo intervenção (p<0.01). Concluímos que pacientes em pós-operatório de cirurgia cardiovascular em ventilação mecânica podem se beneficiar da posição sentada durante o desmame do suporte ventilatório, observado pela melhora da força muscular inspiratória (PImáx). Além disso, não foram observadas alterações hemodinâmicas com a troca de postura, sendo considerado um procedimento seguro.

The purpose was to study the effects of sitting position, in ventilatory and hemodynamic parameters, in patients under prolonged mechanical ventilation, in the postoperative of cardiovascular surgery. Participated 40 postoperative cardiovascular patients, intubated and mechanically ventilated, were randomized into control group (n=17) and intervention group (n=23). Hemodynamic parameters, arterial blood gases, respiratory muscle strength and ventilometry, were measured in two moments: first and second evaluation, with 30-minute interval between measurements. In the control group, both evaluations were performed at head of the bed elevated at 30°. In the sitting group, the first evaluation was developed at 30° and the second, (30 minutes after transfer to the armchair) in the sitting position (90°). The mean age of patients was 64.7±11.2 years. There were no differences regarding the hemodynamic parameters, blood gas analysis, forced vital capacity, minute ventilation and tidal volume. However, a significant increase in maximal inspiratory pressure (MIP) in the intervention group was observed (p<0.01). We conclude that stable patients in the postoperative period of cardiovascular surgery, mechanically ventilated, maybe benefits of the sitting position observed of increased inspiratory muscle strength. Furthermore, no significant hemodynamic changes, and it was well tolerated when the patients were transferred to the sitting position, so it was considered a safe procedure.

Avaliação dos níveis de citocinas e da função pulmonar de pacientes submetidos à cirurgia cardíaca com circulação extracorpórea / Evaluation of cytokine levels and pulmonary function in patients undergoing coronary artery bypass graft / Evaluación de los niveles de citocinas y de la función pulmonar de pacientes sometidos a la cirugía cardíaca con circulación extracorpórea

JUSTIFICATIVA E OBJETIVOS: A Síndrome da Resposta Inflamatória Sistêmica é uma ocorrência habitual em cirurgias cardíacas com circulação extracorpórea (CEC). O objetivo deste estudo foi avaliar os níveis sistêmicos e pulmonares de citocinas e a correlação com a função pulmonar em pacientes submetidos à revascularização miocárdica (RM) com CEC. MÉTODOS: O estudo foi aprovado pela Comissão de Ética institucional, com a avaliação de 13 pacientes submetidos à RM com CEC. Após a indução anestésica, ao término da CEC, realizaram-se dosagens plasmáticas e no lavado broncoalveolar de IL-1β, IL-6, IL-8, IL-10 e TNF-α. Foram avaliados o tempo de CEC e de cirurgia, a relação PaO2/FiO2, o gradiente alvéolo-arterial de oxigênio (GA-aO2), o shunt e a complacência pulmonares. Os resultados foram submetidos à análise de variância para medidas repetidas (*p < 0,05) e coeficiente de correlação de Spearman. RESULTADOS: Observaram-se aumento dos níveis de citocinas no plasma e no lavado broncoalveolar após a CEC e relação direta entre o aumento da IL-1β e a diminuição da complacência pulmonar (p = 0,0439), assim como relação inversa entre o aumento da IL-10 e a redução da complacência (p = 0,0325). O aumento da IL-6 teve relação direta com o tempo de CEC (p = 0,012), enquanto o aumento da IL-8 teve relação direta com o tempo de cirurgia (p < 0,0001). Os níveis de IL-1β, IL-8 e TNF-α foram maiores no LBA em relação ao plasma. CONCLUSÕES: Ocorre aumento dos níveis de citocinas no plasma e lavado broncoalveolar após a CEC e há correlação entre o aumento dos níveis de citocinas e o tempo de CEC e de cirurgia e as alterações na complacência pulmonar.

BACKGROUND AND OBJECTIVES: Systemic inflammatory response syndrome is commonly observed in coronary artery bypass grafts (CABG) with cardiopulmonary bypass (CB). The objective of this study was to evaluate the systemic and pulmonary levels of cytokines and their correlation with lung function in patients undergoing myocardial revascularization (MR) with CB. METHODS: This study was approved by the Institutional Ethics Committee, and 13 patients undergoing MR with CB were evaluated. After anesthetic induction and at the end of CB, plasma and bronchoalveolar lavage levels of IL-1β, IL-6, IL-8, IL-10, and TNF-α were determined. The dur ation of CB and surgery, PaO2/FiO2 ratio, alveolar-arterial oxygen gradient (A-a gradient), shunt, and lung compliance were evaluated. Results were submitted to analysis of variance for repeated measurements (*p < 0.05) and Spearman's correlation coefficient. RESULTS: We observed increased levels of cytokines in plasma and bronchoalveolar lavage after CB and a direct relationship between the increase in IL-1β and decrease in lung compliance (p = 0.0439), as well as the inverse relationship between the increase in IL-10 and a decrease in compliance (p = 0.0325). The increase in IL-6 was directly related to the duration of CB (p = 0.012), while the increase in IL-8 was directly related to the duration of surgery (p < 0.0001). Levels of interleukin-1β, IL-8, and TNF-α in bronchoalveolar lavage were higher than in plasma. CONCLUSIONS: There is an increase in cytokine levels in plasma and bronchoalveolar lavage after CB, as well as a correlation between increased cytokine levels and CB duration and surgery and changes in lung compliance.

JUSTIFICATIVA Y OBJETIVOS: El Síndrome de la Respuesta Inflamatoria Sistémica es algo habitual en las cirugías cardíacas con circulación extracorpórea (CEC). El objetivo de este estudio fue evaluar los niveles sistémicos y pulmonares de citocinas y la correlación con la función pulmonar en los pacientes sometidos a la revascularización miocárdica (RM) con CEC. MÉTODOS: El estudio fue aprobado por la Comisión de Ética Institucional, con la evaluación de 13 pacientes sometidos a la RM con CEC. Después de la inducción anestésica al término de la CEC, se realizaron dosificaciones plasmáticas y también en el lavado broncoalveolar de IL-1β, IL-6, IL-8, IL-10 y TNF-α. Se evaluaron el tiempo de CEC y de cirugía, la relación PaO2/FiO2, el gradiente alvéolo-arterial de oxígeno (GA-aO2), el shunt y la complacencia pulmonares. Los resultados fueron sometidos al análisis de variancia para medidas repetidas (*p < 0,05) y al coeficiente de correlación de Spearman. RESULTADOS: Se observó un aumento en los niveles de citocinas en el plasma y en el lavado broncoalveolar después de la CEC y una relación directa entre el aumento de la IL-1β y la disminución de la complacencia pulmonar (p = 0,0439), como también una relación inversa entre el aumento de la IL-10 y la reducción de la complacencia (p = 0,0325). El aumento de la IL-6 tuvo una relación directa con el tiempo de CEC (p = 0,012), mientras que el aumento de la IL-8 tuvo una relación directa con el tiempo de cirugía (p < 0,0001). Los niveles de IL-1β, IL-8 y TNF-α fueron mayores en el LBA con relación al plasma. CONCLUSIONES: Ocurre un aumento de los niveles de citocinas en el plasma y en el lavado broncoalveolar después de la CEC, con una correlación entre el aumento de los niveles de citocinas y el tiempo de CEC y de cirugía, y las alteraciones en la complacencia pulmonar.

[Evaluation of cytokine levels and pulmonary function in patients undergoing coronary artery bypass graft]. / Evaluación de los niveles de citocinas y de la funciónpulmonar de pacientes sometidos a la cirugía cardíaca concirculación extracorpórea.

BACKGROUND AND OBJECTIVES: Systemic inflammatory response syndrome is commonly observed in coronary artery bypass grafts (CABG) with cardiopulmonary bypass (CB). The objective of this study was to evaluate the systemic and pulmonary levels of cytokines and their correlation with lung function in patients undergoing myocardial revascularization (MR) with CB. METHODS: This study was approved by the Institutional Ethics Committee, and 13 patients undergoing MR with CB were evaluated. After anesthetic induction and at the end of CB, plasma and bronchoalveolar lavage levels of IL-1ß, IL-6, IL-8, IL-10, and TNF-α were determined. The duration of CB and surgery, PaO(2)/FiO(2) ratio, alveolar-arterial oxygen gradient (A-a gradient), shunt, and lung compliance were evaluated. Results were submitted to analysis of variance for repeated measurements (*p < 0.05) and Spearman's correlation coefficient. RESULTS: We observed increased levels of cytokines in plasma and bronchoalveolar lavage after CB and a direct relationship between the increase in IL-1ß and decrease in lung compliance (p = 0.0439), as well as the inverse relationship between the increase in IL-10 and a decrease in compliance (p = 0.0325). The increase in IL-6 was directly related to the duration of CB (p = 0.012), while the increase in IL-8 was directly related to the duration of surgery (p < 0.0001). Levels of interleukin-1ß, IL-8, and TNF-α in bronchoalveolar lavage were higher than in plasma. CONCLUSIONS: There is an increase in cytokine levels in plasma and bronchoalveolar lavage after CB, as well as a correlation between increased cytokine levels and CB duration and surgery and changes in lung compliance.

Hyperkalemia accompanies hemorrhagic shock and correlates with mortality.

OBJECTIVE: This study was designed to evaluate the effects of terlipressin versus fluid resuscitation with normal saline, hypertonic saline or hypertonic-hyperoncotic hydroxyethyl starch, on hemodynamics, metabolics, blood loss and short-term survival in hemorrhagic shock. METHOD: Twenty-nine pigs were subjected to severe liver injury and treated 30 min later with either: (1) 2 mg terlipressin in a bolus, (2) placebo-treated controls, (3) 4 mL/kg 7.5% hypertonic NaCl, (4) 4 mL/kg 7.2% hypertonic-hyperoncotic hydroxyethyl starch 200/0.5, or (5) normal saline at three times lost blood volume. RESULTS: The overall mortality rate was 69%. Blood loss was significantly higher in the hypertonic-hyperoncotic hydroxyethyl starch and normal saline groups than in the terlipressin, hypertonic NaCl and placebo-treated controls groups (p<0.005). Hyperkalemia (K>5 mmol/L) before any treatment occurred in 66% of the patients (80% among non-survivors vs. 22% among survivors, p=0.019). Post-resuscitation hyperkalemia occurred in 86.66% of non-survivors vs. 0% of survivors (p<0.001). Hyperkalemia was the first sign of an unsuccessful outcome for the usual resuscitative procedure and was not related to arterial acidemia. Successfully resuscitated animals showed a significant decrease in serum potassium levels relative to the baseline value. CONCLUSION: Hyperkalemia accompanies hemorrhagic shock and, in addition to providing an early sign of the acute ischemic insult severity, may be responsible for cardiac arrest related to hemorrhagic shock.

Hyperkalemia accompanies hemorrhagic shock and correlates with mortality

OBJECTIVE: This study was designed to evaluate the effects of terlipressin versus fluid resuscitation with normal saline, hypertonic saline or hypertonic-hyperoncotic hydroxyethyl starch, on hemodynamics, metabolics, blood loss and short-term survival in hemorrhagic shock. METHOD: Twenty-nine pigs were subjected to severe liver injury and treated 30 min later with either: (1) 2 mg terlipressin in a bolus, (2) placebo-treated controls, (3) 4 mL/kg 7.5% hypertonic NaCl, (4) 4 mL/kg 7.2% hypertonic-hyperoncotic hydroxyethyl starch 200/0.5, or (5) normal saline at three times lost blood volume. RESULTS: The overall mortality rate was 69%. Blood loss was significantly higher in the hypertonic-hyperoncotic hydroxyethyl starch and normal saline groups than in the terlipressin, hypertonic NaCl and placebo-treated controls groups (p<0.005). Hyperkalemia (K>5 mmol/L) before any treatment occurred in 66% of the patients (80% among non-survivors vs. 22% among survivors, p=0.019). Post-resuscitation hyperkalemia occurred in 86.66% of non-survivors vs. 0% of survivors (p<0.001). Hyperkalemia was the first sign of an unsuccessful outcome for the usual resuscitative procedure and was not related to arterial acidemia. Successfully resuscitated animals showed a significant decrease in serum potassium levels relative to the baseline value. CONCLUSION: Hyperkalemia accompanies hemorrhagic shock and, in addition to providing an early sign of the acute ischemic insult severity, may be responsible for cardiac arrest related to hemorrhagic shock.