Early and late complications among 15 victims exposed to indoor fire and smoke inhalation.

AIM: To evaluate early and late complications among victims exposed to indoor fire and smoke inhalation. METHOD: An observational, descriptive and prospective longitudinal study of 15 victims of smoke inhalation admitted to the intensive care unit. RESULTS: Although without significant burns, 13 of the victims were unconscious, with airway injury, abnormal temperature and hypokalaemia, and underwent mechanical ventilation. Initial carbon monoxide concentration averaged 20.4+/-8.3%, dropping to 3.9+/-3.3% 4h later. On the 1st day, two victims recovered and were transferred, and another two died. Creatine kinase levels (2594+/-2455 U/l) correlated with duration of intensive care. Of the remaining 11 patients, 10 had early pneumonia. Steroid treatment was initiated for four patients receiving prolonged mechanical ventilation, because of persistent fever and dry cough without evidence of infection. CONCLUSIONS: Mortality and systemic involvement were related to burn of the upper airway and contact with combustion products. Initial creatine kinase levels emerged as a prognostic marker of injury severity. Bronchoscopy was useful in grading airway injury and obtaining bronchoalveolar culture. Corticosteroids were effective, after the acute phase, in treating non-infectious pulmonary complications.

Ingreso de pacientes irrecuperables en Terapia Intensiva, no aplicación y suspención de métodos de soporte vital: análisis de una encuesta de opinión / Admission of unrecoverable patients in Intensive Care, non application and suspension of methods of vital supports: analysis of an opinion survey

Las áreas críticas de atención médica, como las unidades de terapia intensiva (UTI), constituyen el escenario clínico donde se aplican métodos invasivos de soporte vital y maniobras de reanimación cardiopulmonar en pacientes cuya recuperabilidad potencial no se evalúa inicialmente. En éste trabajo se analiza una encuesta de opinión efectuada a 93 médicos no especialistas en terapia intensiva sobre el ingreso de pacientes irrecuperables a UTI, la necesidad de limitar el tratamiento a pacientes terminales y ciertos determinantes de la conducta médica en éstas circunstancias. Los resultados indicaron que la presencia frecuente de pacientes irrecuperables en UTI se debe fundamentalmente a exigencias familiares y la carencia de áreas asistenciales adecuadas para la contención del enfermo terminal, circunstancias que pueden favorecer el encarnizamiento terapeútico y la prolongación indefinida de la vida vegetativa. El acuerdo de los médicos en el establecimiento de límites en la atención médica de pacientes irrecuperables parece tener como factores determinantes la desprotección legal de nuestro país para el ejercicio de éstas prácticas y la falta de consenso social sobre éstos temas. El universo médico encuestado no visualiza como equivalentes moralmente la decisión de no actuar respecto de la de dejar de actuar

Ingreso de pacientes irrecuperables en Terapia Intensiva, no aplicación y suspención de métodos de soporte vital: análisis de una encuesta de opinión / Admission of unrecoverable patients in Intensive Care, non application and suspension of methods of vital supports: analysis of an opinion survey

Las áreas críticas de atención médica, como las unidades de terapia intensiva (UTI), constituyen el escenario clínico donde se aplican métodos invasivos de soporte vital y maniobras de reanimación cardiopulmonar en pacientes cuya recuperabilidad potencial no se evalúa inicialmente. En éste trabajo se analiza una encuesta de opinión efectuada a 93 médicos no especialistas en terapia intensiva sobre el ingreso de pacientes irrecuperables a UTI, la necesidad de limitar el tratamiento a pacientes terminales y ciertos determinantes de la conducta médica en éstas circunstancias. Los resultados indicaron que la presencia frecuente de pacientes irrecuperables en UTI se debe fundamentalmente a exigencias familiares y la carencia de áreas asistenciales adecuadas para la contención del enfermo terminal, circunstancias que pueden favorecer el encarnizamiento terapeútico y la prolongación indefinida de la vida vegetativa. El acuerdo de los médicos en el establecimiento de límites en la atención médica de pacientes irrecuperables parece tener como factores determinantes la desprotección legal de nuestro país para el ejercicio de éstas prácticas y la falta de consenso social sobre éstos temas. El universo médico encuestado no visualiza como equivalentes moralmente la decisión de no actuar respecto de la de dejar de actuar (AU)

Argentine Jewish community institution bomb explosion.

BACKGROUND: Descriptive study of physical injuries and implemented organization from a nearby, unwarned university hospital after the July 18, 1994, bombing of the seven-story Argentine Israeli Mutual Association (AMIA) building in Buenos Aires. Data were obtained from hospital medical records. RESULTS: A total of 86 victims arrived at the emergency department, 2 victims were dead on arrival, 41 victims were admitted, and 43 victims with minor injuries were assisted and allowed to go home. The explosion caused a total of 86 deaths and left more than 200 people injured. Mortality rate among hospitalized survivors was 8.3% and among critically injured victims was 28.6%. CONCLUSION: The total collapse of a multiple-story building immediately kills most of its occupants. In the present study, the few surviving victims were located at the lower floors. The majority of hospitalized victims were outside the building at the moment of the blast. Rapid overcrowding of the emergency department with minor and moderate injuries that do not require hospitalization should be anticipated by disaster management plans. Centralization of severely injured patients in critical areas seems appropriate, because this method keeps major cases from spreading through different wards.

[Physiological basis of the clinical course and treatment of shock]. / Bases fisiológicas de la clínica y del tratamiento del shock.

Shock occurs when the circulatory system fails to maintain adequate cellular perfusion, with widespread reduction in delivery of oxygen and other nutrients to tissues. Irreversible cellular injury and multisystem organ failure develop if the condition is not promptly remedied. In cardiogenic, hypovolemic and vascular obstructive shock, systemic vascular resistance is elevated and pulmonary artery oxygenation is decreased. Distributive shock is caused primarily by vasomotor dysfunction resulting in excessive venous pooling, loss of arteriolar tone, and redistribution of blood flow. Cardiac output and intravascular volume may be low, normal or increased in the presence of hypotension in distributive shock. The characteristic pattern of cardiac performance of septic shock is reduced left and right ventricular ejection fractions, increased end-diastolic and end-systolic volumes of both ventricles and normal stroke volumes.

Isoproterenol-dependent decrease in oxygen uptake and respiratory enzyme activities in rat myocardial tissue and mitochondria.

OBJECTIVE: Myocardial damage induced by isoproterenol is believed to be secondary to increased oxygen demands on the heart. Our objective was to test an additional primary action of isoproterenol on tissue and mitochondrial oxidative metabolism and to compare these effects with the effects of other adrenergic agents in the presence of adrenergic inhibitors. DESIGN: Prospective, dose-response study. SETTING: Research laboratory at a university hospital. SUBJECTS: Fifty Sprague-Dawley female rats (200 to 350 g), slightly anesthetized with ether and divided into several groups. INTERVENTIONS: In 26 rats, the heart was removed, cut into fine slices (0.5-mm thickness), and placed in an ice-cold buffer. In 22 animals, the hearts were perfused in the Langendorff manner and chopped and processed for mitochondrial studies. MEASUREMENTS AND MAIN RESULTS: We determined the following: a) the direct "in vitro" effects of isoproterenol and related catecholamines on normal oxygen uptake using myocardial slices; b) rat heart oxygen consumption and mitochondrial oxygen uptake from isolated organs, perfused with isoproterenol; c) measurements of enzyme activities in submitochondrial particles from the same perfused hearts; and d) the direct effects of isoproterenol on normal mitochondria isolated from normal nonperfused hearts. The oxygen uptake was determined polarographically with a Clark-type electrode and enzymatic activities were assayed by spectrophotometric reduction of cytochrome c at 550 nm with different mitochondrial substrates. Isoproterenol (0.01 to 100 nM) decreased the oxygen uptake by the heart slices in a dose-dependent manner. In comparison, epinephrine or norepinephrine per se did not change the parameter. However, with the addition of alpha-adrenergic receptor inhibitors, oxygen uptake decreased to values similar to those values obtained with isoproterenol. Also, mitochondria isolated from hearts perfused with isoproterenol had decreased state 3 respiratory rates (by 50%) and decreased respiratory control ratios (by 30%), without changes in adenosine 5'-diphosphate/oxygen ratios. The respiratory chain enzyme activities were also lowered. CONCLUSIONS: The data suggest that while isoproterenol increases "in vivo" oxygen uptake by the working rat heart, isoproterenol can simultaneously decrease maximal adenosine 5'-diphosphate-induced mitochondrial oxygen uptake and in vitro myocardial tissue oxygen uptake, probably by modifying the mitochondrial respiratory enzymes. This action could be counteracted by alpha-adrenergic agonist effects.

Decreased production of nitric oxide by human neutrophils during septic multiple organ dysfunction syndrome. Comparison with endotoxin and cytokine effects on normal cells.

The objective of this study was to determine nitric oxide (NO) and superoxide anion release (O-2) by neutrophils (PMNs) in the septic multiple organ dysfunction syndrome (MODS) and to compare them with the response of normal cells to lipopolysaccharide (LPS) and cytokines. NO production was measured by the release of nitrites in the medium, its maximal production rate by a modified oxyhemoglobin assay and O-2 by standard methods. Normal cells were incubated with LPS, gamma interferon (IFN-gamma), or tumor necrosis factor (TNF-alpha) alone or in combination. Results showed that PMN release of both NO and O-2 was reduced in septic samples; in contrast, an association of LPS, IFN-gamma, and TNF-alpha promoted maximal NO release by normal cells (40-50%). We conclude that while interaction of normal PMNs with cytokines increases NO and O-2 release, progression of sepsis to a multiple organ dysfunction impairs these responses in both functions.

Active core rewarming in neurologic, hypothermic patients: effects on oxygen-related variables.

OBJECTIVES: To determine in hypothermic patients if a) the decrease in oxygen consumption (VO2) is exclusively dependent on the decrease in metabolic rate, or b) as a consequence of the greater hemoglobin affinity for oxygen, hypothermic tissues have impaired oxygen extraction. DESIGN: Clinical, prospective study; sequential measurements of oxygen-related variables during active core rewarming. SETTING: Intensive care unit of a university hospital. PATIENTS: Twelve patients (44 +/- 16 yrs of age) admitted to the intensive care unit with a core temperature of < 34 degrees C due to severe neurologic damage. INTERVENTIONS: Rewarming (with heated enemas, gastric infusions, and heated blankets) to increase body temperature at a rate of approximately 1 degree C/hr. Measurements of oxygen-related variables were performed at a baseline of 31.0 +/- 1.1 degrees C, and repeated at each 1 degree C increase to reach a core temperature of approximately 35 degrees C. MEASUREMENTS AND MAIN RESULTS: Oxygen-related variables of rewarmed patients were allocated into two groups, above or below the observed mean core temperature of 33.1 degrees C recorded for all measurements (n = 45). Comparison of the low core temperature group (31.1 +/- 1.4 degrees C; n = 20) with the high core temperature group (34.7 +/- 0.9 degrees C; n = 25) showed that the group with the lower core temperatures had a significant increase in VO2 index (67 +/- 22 vs. 103 +/- 38 mL/min/m2 [p < .001]), oxygen delivery index (183 +/- 73 vs. 290 +/- 123 mL/min/m2 [p < .001]), and the PO2 value at which hemoglobin was half-saturated with oxygen ([P50] 23 +/- 5.7 vs. 27.7 +/- 5.7 torr [3.0 +/- 0.7 vs. 3.6 +/- 0.7 kPa] [p < .02]). An increase in metabolic acidosis could be observed in the lower temperature group: arterial pH 7.47 +/- 0.15 vs. 7.34 +/- 0.13 (p < .01); base deficit -3.7 +/- 6.7 vs. -8.2 +/- 4.9 mEq/L (p < .02). The oxygen extraction ratio remained unchanged: 0.39 +/- 0.10 vs. 0.38 +/- 0.10 (NS). CONCLUSIONS: These data show that VO2 was reduced to half of normal values during hypothermia. Active core rewarming produced an average 4.5% increase in VO2 per 1 degree C that was characterized by the wide variation observed in this metabolic response between different patients and for individual cases. Despite the rightward shift of P50 observed during rewarming (mainly due to the Bohr effect), no change was reflected on the oxygen extraction ratio.

Early physiologic changes in canine fecal peritonitis.

Oxygen delivery (DO2) and related variables were studied in eight dogs during severe untreated peritonitis induced by cecal ligation and perforation. The development of peritonitis was accompanied by abdominal fluid sequestration and significant increases in hemoglobin (Hgb), arterial oxygen content (CaO2), and P50. Changes in mixed venous PO2 (P-vO2), mixed venous saturation (S-vO2), DO2, oxygen uptake (VO2), cardiac index (CI), and arteriovenous O2 difference (C[a--v]O2) were not significant. When blood volume was returned to normal levels with dextran, CI rose and C(a--v)O2 decreased; P-vO2 increased and Hgb returned to baseline levels. In this animal model, sepsis and fluid sequestration produced an increase in blood O2 capacity and CaO2, which sustained DO2 and VO2. No changes were observed in P-vO2 or S-vO2. The hyperdynamic state of severe sepsis became evident only after reversing hemoconcentration by colloid infusion. The increase in P-vO2 and S-vO2 after volume loading is possibly related to primary septic mechanisms and/or to changes in DO2.

Captopril versus hydralazine in primary pulmonary hypertension.

Captopril was tested as the treatment for a patient with primary pulmonary hypertension (PPH) and its effects were compared with those of hydralazine. Captopril induced a rise in pulmonary pressures and in intrapulmonary shunt; hydralazine lowered pulmonary resistances and increased paO2 and blood O2 transport. Prospective studies in PPH treated with captopril are recommended and evaluation of all drugs not only by hemodynamic but also respiratory and O2 transport measurements.