Ultrasonographic measurement of the optic nerve sheath diameter to detect intracranial hypertension: an observational study.

OBJECTIVES: To evaluate the ultrasonographic measurement of optic nerve sheath diameter (ONSD) as a predictor of intracranial hypertension as compared to the invasive measurement of intracranial pressure (ICP). DESIGN: Cross-sectional observational study. SETTING: Intensive Care Unit (ICU) of two tertiary university hospitals in Montevideo, Uruguay. PATIENTS: We included 56 adult patients, over 18 years of age, who required sedation, mechanical ventilation, and invasive ICP monitoring as a result of a severe acute neurologic injury (traumatic or non-traumatic) and had a Glascow Coma Score (GCS) equal to or less than 8 on admission to the ICU. INTERVENTIONS: Ultrasonographic measurement of ONSD to detect intracranial hypertension. MEASUREMENTS AND MAIN RESULTS: In our study, a logistic regression model was performed in which it was observed that the variable ONSD is statistically significant with a p value of 0.00803 (< 0.05). This model estimates and predicts the probability that a patient will have an ICP greater than 20 mmHg. From the analysis of the cut-off points, it is observed that a value of 5.7 mm of ONSD maximizes the sensitivity (92.9%) of the method (a greater number of individuals with ICP > 20 mmHg are correctly identified). CONCLUSIONS: In sedated neurocritical patients, with structural Acute Brain Injury, the ONSD measurement correlates with the invasive measurement of ICP. It was observed that with ONSD values less than 5.7 mm, the probability of being in the presence of ICP above 20 mmHg is very low, while for ONSD values greater than 5.7 mm, said probability clearly increases.

Recomendaciones de la Sociedad Uruguaya de Medicina Intensiva sobre los aspectos bioéticos en la pandemia Covid-19 / Recommendations by the Uruguayan Society of Intensive Care on the Covid-19 pandemic / Recomendações da Sociedade Uruguaia de Medicina Intensiva sobre aspectos bioéticos na pandemia Covid-19

Resumen: Introducción: la pandemia provocada por el SARS-CoV-2 genera un importante desafío para el sistema sanitario y especialmente para la Medicina Intensiva. Es necesario prepararse en múltiples aspectos. Además, considerar plausible una demanda extraordinaria de camas críticas que puede llevar a un desbalance entre las necesidades clínicas y la disponibilidad efectiva de los recursos sanitarios. Objetivos: realizar un análisis bioético para brindar una orientación en la atención a los pacientes críticos. Objetivos específicos: 1) Analizar los principios bioéticos fundamentales en este contexto. 2) Apoyar a los clínicos en la toma de decisiones difíciles. 3) Hacer explícitos los criterios de asignación de recursos. 4) Definir líneas de acción ante un posible escenario de "desastre sanitario". Método: la SUMI ha generado un ámbito de trabajo colectivo cuyo método de trabajo fue la deliberación. En la documentación se utiliza la revisión bibliográfica y los protocolos ya existentes. Resultados: el trabajo plantea un análisis teórico documentado sobre los principios bioéticos involucrados en el contexto de pandemia, sobre los escenarios de demanda asistencial y sobre la fundamentación para un cambio en los criterios éticos ante un escenario de saturación del sistema. Conclusión: se plantean recomendaciones prácticas para: 1) Toma de decisiones de ingreso y egreso en demanda controlada. 2) Criterios de acción ante el aumento de la demanda estableciendo definiciones de los diferentes escenarios. 3) Recomendaciones para aplicar en un escenario de saturación del sistema.

Summary: Introduction: the pandemic caused by SARS-CoV2 constitutes a significant challenge for the health system, and especially for Critical Care Units, so we need to prepare in many aspects. Likewise, we need to consider there could be an extraordinary demand for beds in critical care units, what would lead to an imbalance between clinical needs and the effective availability of health resources. Objectives: the study aims to perform a bioethical analysis that could provide guidelines for the assistance of patients in critical care. Specific objectives: 1) to analyse the main bioethical principles in this context, 2) to support clinicians in the making of difficult decisions, 3) to make the resource allocation criteria specific, 4) to define action lines upon a potential "health's disastrous" scenario Method: the Uruguayan Society of Intensive Care has generated a space for collective work based on discussion processes. Documents include a bibliographic review and the existing protocols. Results: the study presents a theoretical analysis that is backed up by the bioethical principles involved in the pandemic context on the scenarios of demand for assistance and, by the arguments calling for a change in the ethical criteria upon the saturation of the health system. Conclusion: practical recommendations are made: 1) for the making of decisions about admission and discharge in a controlled demand. 2) to define action criteria upon an increase in demand, clearly defining the different scenarios, 3) to apply upon the saturation of the health system.

Resumo: Introdução: a pandemia causada pelo SARS-CoV2 gera um importante desafio para o sistema de saúde e principalmente para a Medicina Intensiva. É preciso se preparar em vários aspectos. Além disso, considera plausível uma demanda extraordinária por leitos críticos, que pode levar a um desequilíbrio entre as necessidades clínicas e a disponibilidade efetiva de recursos de saúde. Objetivos: realizar uma análise bioética para orientar o cuidado ao paciente crítico. Objetivos específicos: 1) Analisar os princípios bioéticos fundamentais neste contexto, 2) Apoiar os médicos na tomada de decisões difíceis, 3) Tornar explícitos os critérios de alocação de recursos, 4) Definir linhas de ação perante um possível cenário de " desastre de saúde ". Métodos: a SUMI gerou um ambiente de trabalho coletivo cujo método de trabalho era deliberativo. A documentação usa a revisão da literatura e os protocolos existentes. Resultados: o trabalho propõe uma análise teórica documentada sobre os princípios bioéticos envolvidos no contexto da Pandemia, sobre os cenários da demanda de saúde e sobre os fundamentos para uma mudança de critérios éticos em um cenário de saturação do sistema. Conclusão: são propostas recomendações práticas para: 1) tomada de decisão para admissão e alta sob demanda controlada. 2) critérios de atuação frente ao aumento da demanda, estabelecendo definições dos diferentes cenários. 3) recomendações a serem aplicadas em um cenário de saturação do sistema.

Comparison of ultrasonographic versus infrared pupillary assessment.

OBJECTIVES: To evaluate the correlation between ultrasonographic and infrared pupillary assessments in critically ill patients, including neurocritically ill patients. DESIGN: Prospective, observational study. SETTING: Tertiary teaching hospital intensive care unit (ICU) in Montevideo, Uruguay. PATIENTS: Twenty-six adults patients with age 18 or older admitted to the intensive care unit with and without neurologic pathology. A total of 212 pupillary measures were made between ultrasonographic pupillary assessment (UPA) and infrared pupillary assessment (IPA). INTERVENTIONS: This was a study that utilized non-invasive (minimal risk) ultrasonographic and infrared pupillary assessment in patients admitted to the ICU. Time between UPA and IPA in a single patient was consistently less than 3 min. MEASUREMENTS AND MAIN RESULTS: There was a strong positive association between UPA and IPA (right eye [OD]: r = de 0.926, p-value < 0.001; left eye [OS], r = 0.965, p-value < 0.001), also observed in the group of neurocritically ill patients (OD: r = 0.935, p-value < 0.001; OS: r = de 0.965, p-value < 0.001). Taking IPA as reference measure, the percent error for all subjects was 2.77% and 2.15% for OD and OS, respectively, and for neurocritically ill patients it was 3.21% and 2.44% for OD and OS, respectively. CONCLUSIONS: Ultrasonographic pupillary assessment is strongly correlated with infrared pupillary assessment in critically ill patients, including neurocritically ill patients. Ultrasonographic pupillary assessment is a quick, feasible, non-invasive method that allows accurate pupillary assessment, particularly neurologic function, in patients in whom a more precise measurement of the pupil is required or eye opening is not possible (e.g., periorbital edema due to traumatic brain injury).

Impact of an ultrasound-driven diagnostic protocol at early intensive-care stay: a randomized-controlled trial.

BACKGROUND: Point-of-care ultrasound (POCUS) is a tool in increasing use, but there is still a lack of basics for its routine use and evidence of its impact in intensive care. OBJECTIVE: To measure the impact of POCUS on resource utilization, diagnostic accuracy, and clinical management in medical-surgical intensive care units (ICUs). METHODS: Prospective, controlled study, in two polyvalent ICUs. The patients were randomly assigned to POCUS or control group. INTERVENTIONS: POCUS patients received systematic ultrasound examination of optic nerve, lung/pleura, heart, abdomen, and venous system, performed at the bedside by trained intensivists. Control patients were treated by critical care specialists who do not perform ultrasound in their clinical practice. RESULTS: We included 80 patients, 40 per group. There were no significant differences in age, sex, APACHE II score, or admission diagnosis. POCUS group used fewer resources per patient in the first 5 days of hospitalization: chest radiography (2.6 ± 2.0 vs 4.1 ± 3.5, P = 0.01), additional ultrasound evaluations performed by a radiology specialist (0.6 ± 0.7 vs 1.1 ± 0.7, P = 0.002), and computed tomography studies (0.5 ± 0.6 vs 0.9 ± 0.7, P = 0.007). Time to perform any requested ultrasound evaluation after ICU admission was 2.1 ± 1.6 h versus 7.7 ± 6.7 h (P = 0.001). Systematic ultrasound evaluation led to better characterization of ICU admission diagnosis in 14 (35%) patients and change in clinical management in 24 (60%). POCUS group had lower fluid balance at 48 and 96 h after admission (P = 0.01) and spent less time mechanically ventilated (5.1 ± 5.7 days vs 8.8 ± 9.4, P = 0.03). CONCLUSIONS: Systematic application of POCUS may decrease utilization of conventional diagnostic imaging resources and time of mechanical ventilation, and facilitate meticulous intravenous fluid administration in critically ill patients during the first week of stay in the ICU. Trial registration ClinicalTrials.gov Identifier: NCT03608202.

Miocarditis fulminante / Fulminant myocarditis

La miocarditis es una enfermedad inflamatoria del músculo cardíaco, es una causa importante en todo el mundo de miocardiopatía dilatada. La infección viral es también una importante causa de miocarditis, y el espectro de los virus que causan la miocarditis ha cambiado en las últimas dos décadas. Su manifestación clínica principal, aunque no exclusiva, es un cuadro de insuficiencia cardíaca aguda. Presentamos el caso de una paciente cursando un cuadro de filiación cardiovascular, caracterizado por dolor torácico, falla cardíaca y arritmias malignas, en que se realizó diagnóstico de miocarditis con evolución fulminante. Se realizó monitoreo hemodinámico avanzado y medidas de soporte circulatorio mecánico con malos resultados clínicos...

Myocarditis is an inflammatory disease of the heart muscle, and globally, it is an important cause of dilated cardiomyopathy. Viral infection is also an important cause of myocarditis, and the range of virus causing myocarditis has changed in the last two decades. Acute heart failure is its main clinical manifestation, although it is not exclusive.The study presents a patient under a cardiovascular condition characterized by thoracic pain, heart failure and malignant arrhythmias. Myocarditis was diagnosed and evolution was fulminant. Advanced hemodynamic monitoring was performed and mechanical circulatory support measures were taken, clinical results being bad...

A miocardite é uma enfermidade inflamatória do músculo cardíaca sendo, em todo o mundo, uma causa importante de cardiomiopatia dilatada. A infecção viral também é uma causa importante de miocardite, e o espectro dos vírus que a causa mudou nas últimas duas décadas. Sua manifestação clínica principal, embora não exclusiva, é um quadro de insuficiência cardíaca aguda.Apresentamos o caso de uma paciente com um quadro cardiovascular, caracterizado por dor torácica, falha cardíaca e arritmias malignas, com diagnóstico de miocardite de evolução fulminante. Fez-se monitoramento hemodinâmico avançado e foram realizadas medidas de suporte circulatório mecânico com resultados clínicos ruins...

Hematoma retrofaríngeo: a propósito de un caso / A case of retropharyngeal hematoma

El hematoma retrofaríngeo de causa traumática es una entidad clínica muy poco frecuente. Por la proximidad con la vía aérea superior y por tratarse de una lesión ocupante de espacio a nivel de los planos profundos del cuello, la misma puede producir la rápida instalación de una insuficiencia respiratoria aguda de tipo obstructivo. Presentamos el caso de un paciente de sexo masculino, de 72 años, que sufre un siniestro de tránsito, moto contra moto, como conductor sin casco. Es asistido en la vía pública por unidad de emergencia móvil prehospitalaria (UEMPH), que constata: traumatismo encéfalo-craneano (TEC) sin pérdida de conocimiento. Se otorga el alta a domicilio desde el lugar del accidente. Reconsulta en domicilio por cuadro de dificultad respiratoria de rápida instalación y edema de cuello. Valorado nuevamente por UEMPH en domicilio, se constata: polipnea, estridor, disfonía. Se realiza traslado en ambulancia a emergencia del Hospital de Clínicas donde se realiza intubación orotraqueal (IOT), asistencia respiratoria mecánica (ARM) y con diagnóstico tomográfico de hematoma retrofaríngeo ingresa a la unidad de cuidados intensivos (UCI). En la evolución se realizó traqueostomía quirúrgica (TQTq) y tratamiento conservador con buena evolución. El hematoma retrofaríngeo traumático es una entidad poco frecuente de gravedad potencial o real que debe conocerse para no demorar su diagnóstico. Una vez que la vía aérea se encuentra asegurada, se presentan dos opciones: drenaje del hematoma u observación clínica. La opción quirúrgica no ha mostrado ventajas respecto al tratamiento conservador.

Retropharyngeal edema caused by trauma is a rather unusual clinical entity. Given its close proximity to the upper airway and being a lesion that occupies space in the deep planes of the neck it may result in a fast installation of acute respiratory distress.The study presents the case of a male patient of 72 years old who suffered a car accident, where two motorbikes took part, and he was not wearing a helmet. He was seen in the site by the mobile emergency services who found: traumatic brain injury (TBI) with no unconsciousness. He was released to go home. The patient consulted again from his domicile for difficulties in breathing of rapid installation and neck swelling. He was assessed by emergency services in his domicile which found: polypnea, stridor and dysphonia. He was sent to the Emergency Unit at the Clinicas University Hospital in an ambulance where orotracheal intubation was performed, he received mechanical ventilation. The scan diagnosis was retropharyngeal edema and he was admitted in the ICU. Upon evolution a surgical tracheostomy was performed and a conservative treatment resulted in a favorable evolution. Traumatic retropharyngeal edema is rather an unusual condition with a potential or real severity that needs to be known to avoid delaying diagnosis. Once the airway is ensured two options are possible: draining the area or clinical observation. The surgical option has evidenced no advantages when compared to a conservative treatment.

O hematoma retrofaríngeo de origem traumática é uma entidade clínica muito pouco frequente. Por sua proximidade com a via aérea superior e por ser uma lesão que ocupa espaço na área dos planos profundos do pescoço, pode produzir rapidamente uma insuficiência respiratória aguda de tipo obstrutivo.Apresentamos o caso de um paciente de sexo masculino, de 72 anos, que teve um acidente de trânsito, motocicleta contra motocicleta, no qual era condutor e estava sem capacete. Foi atendido na via pública por uma unidade de emergência móvel pré-hospitalar (UEMPH), que constatou: traumatismo cranioencefálico (TCE) sem perda de consciência. No lugar do acidente recebeu alta. Consultou novamente no domicilio por quadro de dificuldade respiratória de instalação rápida e edema de pescoço. Avaliado novamente por uma UEMPH no domicilio, foi constatada: polipneia, estridor, disfonia. Foi transferido em uma ambulância ao pronto-socorro do Hospital das Clínicas aonde foi submetido a intubação orotraqueal (IOT), assistência respiratória mecânica (ARM); com diagnóstico tomográfico de hematoma retrofaríngeo foi internado na unidade de cuidados intensivos (UCI). Foram realizados uma traqueostomia cirúrgica (TQTc) e tratamento conservador com boa evolução. O hematoma retrofaríngeo traumático é uma entidade pouco frequente, com gravidade potencial ou real e que deve ser conhecido para evitar demora no seu diagnóstico. Quando a via aérea estiver assegurada, existem duas opções: drenagem do hematoma ou observaçao clínica. A alternativa cirúrgica não tem apresentado vantagens com relação ao tratamento conservador.

Polyclonal endemicity of Acinetobacter baumannii in ventilated patients in an intensive care unit in Uruguay.

OBJECTIVES: To identify the mechanisms responsible for respiratory infections by Acinetobacter baumannii in intubated patients and risk factors for digestive colonization and infection by A. baumannii. METHODS: We conducted a prospective study in an intensive care unit (ICU) between May 2005 and November 2006, including 175 consecutive patients at the beginning of invasive ventilation (day 1). We performed pharyngeal and rectal swabs on days 1, 4, 7, 10, 13, and 16. Respiratory samples were taken on days 1 and 7, or on suspicion of ventilator-associated pneumonia (VAP). RESULTS: We detected 62 patients with A. baumannii digestive colonization and 20 cases of A. baumannii lower respiratory infection (14 VAP and six purulent tracheobronchitis (PTB)). Digestive colonization by A. baumannii was an independent risk factor for lower respiratory tract infections with that microorganism (p<0.0001; relative risk 8.71, 95% confidence interval 2.73-27.77). Respiratory and rectal A. baumannii isolates from the same patients were compared by enterobacterial repetitive intergenic consensus (ERIC)-PCR; in 9/11 cases (eight VAP and one PTB) results suggested events of exogenous pneumonia with previous colonization, whereas the remaining two cases (two PTB) were suggestive of exogenous infection without previous colonization. CONCLUSIONS: In our unit the pathogenesis of VAP by A. baumannii is mixed, most cases corresponding to exogenous pneumonia with previous colonization.

Prospective study of risk factors for ventilator-associated pneumonia caused by Acinetobacter species.

UNLABELLED: The incidence of ventilator-associated pneumonia (VAP) by Acinetobacter spp (VAPA) is increasing and has high morbidity and mortality. It is imperative to identify risk factors to be able to use prevention policies. OBJECTIVE: The aim of this study was to identify specific risk factors for VAPA. DESIGN: Prospective cohort study. INTERVENTIONS: None. SETTING: Two medical-surgical intensive care units. MEASUREMENTS: During a period of 36 months, all patients with more than 48 hours on mechanical ventilation and suspected of having a VAP were enrolled. Only VAP with microbiological confirmation was analyzed. RESULTS: Two hundred eighteen consecutive patients with clinical suspicion of VAP were enrolled. One hundred twenty-five VAPs were confirmed by culture--46 by Acinetobacter spp and 79 by other pathogens. The 36 potential risk factors for Acinetobacter spp were analyzed by univariate analysis. Logistic regression identified previous use of ceftriaxone (relative risk, 5.1; 95% confidence interval, 1.47-17.82) and previous use of ciprofloxacin (relative risk, 9.1; 95% confidence interval, 2.29-36.63) as significant independent predictors for the development of VAPA. CONCLUSIONS: Previous use of ceftriaxone and ciprofloxacin are independent risk factors for the development of VAPA.

Heart rate variability as early marker of multiple organ dysfunction syndrome in septic patients.

PURPOSE: To determine whether measuring heart rate variability (HRV) in a group of septic patients without multiple organ dysfunction syndrome (MODS) made it possible to predict which of them would later develop this syndrome. MATERIAL AND METHODS: We studied 46 septic patients without MODS at the time of admission to an intensive care unit (ICU). During the first 24 hours of admission, a 10-minute electrocardiogram (ECG) was performed and 8 HRV indexes were calculated off-line. Eleven patients later developed MODS (MODS group) during their ICU stay, and 28 did not (non-MODS group). Seven patients were excluded. RESULTS: Although Acute Physiological and Chronic Health Evaluation (APACHE II) scores were similar for both groups, most HRV indices on admission were reduced significantly in the MODS group. Compared with a subset from the non-MODS group (control group, n = 11) paired by age, the MODS group had significantly lower low-frequency spectral components (LF, P =.0128) and mean squared successive differences of R-R intervals (rMSSD) (P =.0473) values. Multivariable logistic regression identified LF as the best predictor of MODS and received operating characteristic (ROC) curves established its cut-off point at 18 ms(2). Mortality rates were 63.6% for the MODS group and 0% for the non-MODS group (P <.0001). CONCLUSIONS: Reduction of HRV on ICU admission may be useful in identifying septic patients at risk for development of MODS.

Factores de riesgo para desarrollar neumonía asociada a la ventilación por Acinetobacter spp / Risk factors for developing ventilation-associated pneumonia due to Acinetobacter spp

La incidencia de neumonía asociada a la ventilación (NAV) por Acinetobacter spp. a nivel nacional e internacional es creciente y determina una elevada mortalidad atribuible. Los factores de riesgo para adquirir una neumonía por este patógeno varían en los diferentes centros. El objetivo del trabajo fue identificar los factores de riesgo específicos para adquirir NAV por Acinetobacter spp. El estudio clínico prospectivo se realizó durante un período de 24 meses (entre mayo del año 2000 a mayo del año 2002) en las unidades de cuidados intensivos (UCI) del Hospital Pasteur y Hospital Policial. Se incluyeron todos los pacientes ventilados por un período mayor o igual a 48 horas que tuvieran sospecha de estar desarrollando una NAV. Se analizaron solo las neumonías bacteriológicamente confirmadas. Resultados: se enrolaron 137 pacientes por tener sospecha clínica de NAV, de los que 77 episodios de NAV fueron bacteriológicamente confirmados: 27 por Acinetobacter spp. y 50 por otros patógenos. Los datos fueron analizados en un modelo de regresión logística donde la variable dependiente fue Acinetobacter spp. El uso previo de ceftriaxona (CRO) (p=0,0001, OR=11,2) y el uso previo de fluorquinolonas (p=0,003, OR=7,0) predicen significativamente y en forma independiente el desarrollo de NAV por Acinetobacter spp. Conclusiones: se identificaron como factores de riesgo para desarrollar NAV por Acinetobacter spp. el uso previo de CRO y fluorquinolonas. Se sugiere la restricción de ceftriaxona - fluorquinolonas y rotación con otras moléculas de espectro similar.

Summary The incidence of pneumonia associated with Acinetobacter spp.-ventilation (PAV) has risen both at national and international levels and determines high mortality rates. Risk factors for developing this hospital-acquired pneumonia vary in every centre. We aimed at identifying specific risk factors for developing PAV. This 24-month prospective study (May 2000-May 2002) took place in the intensive care units (IUC) of the Hospital Pasteur and the Hospital Policial. All ventilated patients for a period of 48 hours or more, suspected to carry PAV were enrolled. Only pneumonias bacterial-proved were analyzed. Results. In a sample of 137 patients, suspected carriers of PAV, 77 PAV events were bacterial-proved: 27 for Acinetobacter spp. and 50 for other pathogens. Logistic regression was used to analyze data, the independent variable was Acinetobacter spp. Previous use of ceftriaxone (CRE) (p = 0,0001, OR = 11,2) and flurquinolone (p=0,003, OR=7,0) significant and independently predicted PAV. Conclusions. CRE and fluorquinolone were indentified as risk factors for developing PAV. Restriction on CRE and fluorquinolone and use of other molecules of similar spectrum in rotation.

Résumé L'incidence de pneumonie associée à la ventilation (NAV) par Acinetobacter spp. au domanine national et interna-tional est croissante et détermine un ehaite mortalité attribuable. Les facteurs de risque pour acquérir une pneu-monie par ce pathogène varient aux différents centres. Le but de ce travail a été d'identifier les facteurs de risque spécifiques pour acquérir NAV par Acinetobacter spp. L'étude clinique prospective a été faite pendant une période de 24 mois (entre mai 2000 et mai 2002) aux unités de soins intensifs (UCI) de l'Hôpital Pasteur et de l'Hôpital Policier. On a inclu tous les patients ventilés pour une période de 48 heures ou plus qui soient soupçonnés de développer une NAV. On n'a analysé que les pneumonies bactériologiquement confirmées. Résultats: 137 patients à soupçon clinique de NAV, dont 77 épisodes de NAV ont été confirmées bactériolo-giquement: 27 par Acinetobacter spp. et 50 par d'autres pathogènes. Les données ont été analysées dans un modèle de régression logistique où la variable dépendante a été Acinetobacter spp. L'emploi préalable de cephriaxone (CRO) (p=0,0001, OR=11,2) et l'emploi préalable de fluorquinolones (p=0,0003, OR=7,0) prédisent remar-quablement et de manière indépendante le développement de NAV par Acinetobacter spp. Conclusions: On a identifié comme facteurs de risque pour développer NAV par Acinetobacter spp. l'emploi préalable de CRO et de fluorquinolones. On suggère la restriction de cephriaxone-fluorquinolones et rotation avec d'autres molécules à spectre semblable.

Estudio de la fase de relajación del ventrículo derecho / Study of the relaxation phase of the right ventricle

El propósito de este trabajo fue investigar la existencia o no de una fase de relajación isovolumétrica en el ventrículo derecho en animales de experimentación con presión normal en la arteria pulmonar. Fueron registradas simultáneamente las presiones del ventrículo izquierdo, aorta (microtransductores), flujo pulmonar, diámetros ventriculares (sonomicrómetro), en 10 ovejas anesteciadas con pentobarbital intravenoso se obtuvo fuera de línea la primera deriva de las presiones ventriculares, los volúmenes ventriculares y los bucles presión-volumen de ambos ventrículos. El volumen sistólico mínimo ventricular derecho coincidió con el flujo pulmonar O, y ambos con un valor de presión diastólica de 0.5 mmHg en dicho ventrículo. Alcanzado el volumen sistólico mínimo, se inicia un rápido ascenso de la curva de volumen ventricular derecho. El bucle presión-volumen del ventrículo derecho, a diferencia del bucle del ventrículo izquierdo, adoptó una forma no rectangular. La fase eyectiva del ventrículo derecho se extendió hasta el inicio del llenado siguiente. Se concluye que, en el ventrículo derecho, no existe fase de relajación insovulométrica