Asunto(s)
Agonistas Adrenérgicos beta/administración & dosificación , Dopamina/análogos & derivados , Mucosa Intestinal/metabolismo , Consumo de Oxígeno/efectos de los fármacos , Animales , Velocidad del Flujo Sanguíneo , Enfermedad Crítica/terapia , Dopamina/administración & dosificación , Humanos , Intestinos/irrigación sanguínea , Circulación Esplácnica/fisiologíaRESUMEN
Many of our patients in ICUs suffer from shock, be it due to sepsis, trauma, arrest, or other causes. These patients continue to have a very high mortality rate in spite of very labor intensive and expensive treatment. The ability to identify patients who are likely to succumb to their illness is of utmost importance. Of the multitude of scoring systems published, the APACHE seems to accurately stratify shock patients according to severity of illness. However, these systems tend to be more useful for stratifying risk groups of patients than assessing the risk of death. Hemodynamic data can specifically assess the severity of the shock state in an individual patient. Those who maintain a relatively low cardiac index (< 4.5 L/m/M2) and oxygen delivery (< 15 mL/m/kg or 600 mL/m/M2) have persistent tissue hypoperfusion. Arterial lactate concentrations reflect the severity of this perfusion defect and correlate with outcome. Therefore, by restoring tissue perfusion, we can clearly improve mortality. CPP, although not generally obtainable during cardiac arrest, is the major physiologic determinant of outcome from CPR. ETCO2 monitoring during cardiac arrest in humans correlates with resuscitability, however, provides a rapid noninvasive monitor of cardiac output, and therefore has secured its role as an invaluable tool for assessing the effectiveness of CPR. An ETCO2 over 10 mm Hg is associated with effective CPR. A rapid rise in ETCO2 during CPR heralds recovery of spontaneous circulation. In conclusion, the use of prognostic indicators as predictors of outcome is supported as an important adjunct to the management of critically ill patients. These indicators serve as useful monitors to evaluate treatment and guide clinical management. Understanding the underlying pathophysiologic mechanisms responsible for the wide variety of illnesses associated with circulatory failure is crucial in our concerted effort to reduce mortality in these patients. As knowledge is gained, we hopefully will be able to develop more accurate and specific predictors of outcome to prudently select patients most likely to benefit.
Asunto(s)
Reanimación Cardiopulmonar/mortalidad , Cuidados Críticos , Paro Cardíaco/clasificación , Paro Cardíaco/mortalidad , Hemodinámica , Índice de Severidad de la Enfermedad , Choque/clasificación , Choque/mortalidad , Resultado del Tratamiento , Cuidados Críticos/organización & administración , Enfermedad Crítica , Predicción , Paro Cardíaco/sangre , Paro Cardíaco/fisiopatología , Paro Cardíaco/terapia , Mortalidad Hospitalaria , Humanos , Monitoreo Fisiológico , Pronóstico , Choque/sangre , Choque/etiología , Choque/fisiopatología , Choque/terapiaRESUMEN
Septic shock is characterized by hypoperfusion and tissue energy defects. We prospectively evaluated the therapeutic benefit of augmenting cardiac output and therefore oxygen delivery (DO2) on mortality in patients with septic shock. Twenty-five patients were randomized to a normal treatment (NT) group and 26 patients were randomized to an optimal treatment (OT) group. All patients had a clinically evident site of infection, sepsis as defined by a systemic response to the infection, and shock indicated by systemic hypoperfusion. Patients were treated during the initial 72 h by an algorithm differing only in the end point of resuscitation. The cardiac index (CI) was increased to 3.0 L/min/m2 in the NT group and to 6 L/min/m2 in the OT group. There were no significant differences in cardiorespiratory parameters in the NT and OT groups on entrance into the study. During treatment, CI averaged 3.6 +/- 0.2 L/min/m2 and DO2 averaged 8.6 +/- 0.8 ml/min/kg in the NT group and CI averaged 5.1 +/- 0.2 L/min/m2 and DO2 averaged 12.2 +/- 0.7 ml/min/kg in the OT group (p less than 0.01). A significant correlation between DO2 and survival was observed. Seventy-two percent of the OT patients died vs 50 percent of the NT patients (p = 0.14). Surviving NT patients stayed 13.7 +/- 3 days in the ICU vs 7.4 +/- 0.6 days (p less than 0.05) for the OT patients. Since some of the NT patients were spontaneously hyperdynamic and some of the OT patients did not achieve their desired end point, patients were arbitrarily subsetted using a midpoint CI of 4.5 L/min/m2. The NT less than 4.5 group had a CI of 3.1 +/- 0.2 L/min/m2 and DO2 of 10.9 +/- 1.0 ml/min/kg while the OT group greater than 4.5 L/min/m2 had a CI of 5.7 +/- 0.2 L/min/m2 and a DO2 of 13.8 +/- 0.7 ml/min/kg (p less than 0.01). Mortality in the NT less than 4.5 group was 74 percent as compared with 40 percent in the OT greater than 4.5 group (p less than 0.05).
Asunto(s)
Albúminas/uso terapéutico , Gasto Cardíaco , Dopamina/uso terapéutico , Oxígeno/sangre , Choque Séptico/terapia , Algoritmos , Humanos , Persona de Mediana Edad , Respiración con Presión Positiva , Estudios Prospectivos , Choque Séptico/sangre , Choque Séptico/mortalidad , Tasa de SupervivenciaRESUMEN
This review article examines the pathophysiology of septic shock, with special attention to the concept of supply-dependent consumption and the implications this concept has for therapy. Patients with septic shock require higher levels of oxygen delivery (DO2) to maintain aerobic metabolism. When DO2 is inadequate, peripheral tissues switch to anaerobic metabolism and oxygen consumption decreases. The lactic acidosis that occurs is a reasonable clinical marker of supply dependency and inadequate tissue perfusion. Maximizing DO2 is an important part of the hemodynamic resuscitation of patients with septic shock. To achieve this goal, intravascular volume must be restored and the myocardial depression associated with sepsis must be treated to optimize cardiac output. The normalization of arterial lactate concentration is a reasonable goal of resuscitative efforts.
Asunto(s)
Infecciones Bacterianas/metabolismo , Consumo de Oxígeno , Choque Séptico/metabolismo , Infecciones Bacterianas/fisiopatología , Infecciones Bacterianas/terapia , Hemodinámica , Humanos , Choque Séptico/fisiopatología , Choque Séptico/terapiaRESUMEN
A feasibility study was undertaken prospectively to identify early clinical and laboratory factors predictive of acute hospital mortality in patients with the acquired immunodeficiency syndrome and concurrent Pneumocystis carinii pneumonia. Twenty-six patients hospitalized with bronchoscopy-proved P carinii pneumonia were studied. Nineteen patients survived their episode of P carinii pneumonia, while 7 subjects did not. The only clinical factor associated with mortality was a history of a shorter duration of pulmonary symptoms. Univariate analysis showed decreased total CD8 cell count, total lymphocyte count, serum hemoglobin, serum albumin, total thyroxine, and total triiodothyronine values consistent with a poor outcome. Multivariate logistic regression analysis showed that the single best prognostic indicator of acute mortality appeared to be a total serum triiodothyronine value less than 0.70 nmol/L obtained early in the hospital course, and that the combination of serum triiodothyronine and hemoglobin values provided a better indication for survival. These preliminary observations would appear to justify the further exploration of serial serum triiodothyronine measurements as a potentially valuable prognostic indicator for the treatment of patients with acquired immunodeficiency syndrome infected with P carinii and possibly other intercurrent infectious illnesses.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Neumonía por Pneumocystis/sangre , Triyodotironina/sangre , Adulto , Estudios de Factibilidad , Femenino , Hemoglobinas/análisis , Humanos , L-Lactato Deshidrogenasa/sangre , Linfopenia/sangre , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Neumonía por Pneumocystis/diagnóstico por imagen , Neumonía por Pneumocystis/mortalidad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Radiografía , Albúmina Sérica/metabolismo , Hormonas Tiroideas/sangreRESUMEN
In this retrospective study, we attempted to identify early in the course of septic shock hemodynamic variables that differ between survivors and nonsurvivors. We examined the records of 78 patients with septic shock from our medical ICU (40 survivors and 38 nonsurvivors). Significant differences were found in cardiac index (CI) (4.07 +/- 0.25 vs. 2.98 +/- 0.25 L/min.m2) and oxygen delivery (DO2) (15.6 +/- 0.7 vs. 12.7 +/- 0.8 ml/min.kg) at 48 h between surviving and nonsurviving patients. Furthermore, an analysis of the relationship between DO2 and VO2 suggests a critical level of DO2 to be 15 ml/min.kg. Although no difference could be detected in initial arterial lactate concentrations, levels at 48 h were significantly different between survivors and nonsurvivors (2.6 +/- 0.2 vs. 4.1 +/- 0.5 mEq/L, respectively).
Asunto(s)
Hemodinámica , Choque Séptico/mortalidad , Adulto , Femenino , Humanos , Lactatos/sangre , Masculino , Persona de Mediana Edad , Consumo de Oxígeno , Estudios Retrospectivos , Choque Séptico/metabolismo , Choque Séptico/fisiopatologíaRESUMEN
Previous reports have shown hemodynamic data inaccurately predicted by physical examination and x-ray findings. Although invasive hemodynamic monitoring has been shown to significantly alter the management of critically ill patients, the impact on mortality has been difficult to assess. In a prospective study of 35 patients, we found inaccurate predictions of left and right heart filling pressures by clinical assessment. However, cardiac output was accurately estimated. Management was altered 34% of the time because of invasive hemodynamic assessment; however, mortality was not affected by a change in therapy.
Asunto(s)
Cateterismo Cardíaco , Hemodinámica , Unidades de Cuidados Intensivos , Monitoreo Fisiológico , Adulto , Humanos , Mortalidad , Estudios Prospectivos , Arteria PulmonarRESUMEN
Since its introduction in 1969, the balloon-tipped pulmonary artery catheter has become widely accepted. Pulmonary capillary wedge pressures have been used diagnostically to determine left ventricular preload and volume status. We report on a patient with noncardiogenic pulmonary edema, secondary to a heroin overdose, who was hypovolemic and had an elevated pulmonary capillary wedge pressure. We discuss possible explanations and present evidence that the pulmonary capillary wedge pressure does not always accurately reflect volume status.
Asunto(s)
Presión Esfenoidal Pulmonar , Choque/fisiopatología , Adulto , Volumen Sanguíneo , Diagnóstico Diferencial , Hemodinámica , Dependencia de Heroína/complicaciones , Humanos , Masculino , Edema Pulmonar/etiología , Edema Pulmonar/fisiopatología , Choque/diagnóstico , Choque/etiologíaRESUMEN
The wounds of 60 burned patients were treated topically with cerium nitrate, which was applied either as a cream or in aqueous solution. Cerium nitrate has a potent antiseptic effect in human burn wounds, especially against gram negative bacteria and fungi. Pseudomonas aeruginosa was recovered from the wounds infrequently and never predominated. Fungi were practically never found. No patient treated with cerium developed a necrotizing wound infection. Analysis of the detailed bacteriological data indicated that, in contrast to previous results with use of the nitrate or sulfadiazine salts of silver, when gram negative species predominated, the flora tended to be predominantly gram positive when cerium was used. Therefore, some patients were treated simultaneously with cerium nitrate and silver sulfadiazine; this resulted in an even more efficient suppression of the wound flora than was observed previously with either cerium alone or silver salts alone; results with the simultaneous topical therapy in patients with injuries that previously were uniformly lethal were excellent. No toxicity attributable to the use of cerium was observed, although one instance of methemoglobinemia due to nitrate was documented. The adsorption of topically applied cerium essentially is nil. The use of cerium nitrate was associated with a nearly 50 percent reduction in the anticipated death rate. Cerium nitrate is a promising new topical antiseptic agent for the treatment of burns, particularly when it is used in combination with silver sulfadiazine.