RESUMEN
We developed methodology for prospective randomized effectiveness studies using a demonstration project at a multispecialty practice, health maintenance organization, and hospital in academic medical center. An operational unit called the effectiveness registry was developed to design and support comparisons of potential practice improvements with standard care. The studies differ from observational effectiveness studies in that they provide long-term follow-up of randomized comparison groups. Physician involvement in data collection is limited. No tests or observations are made other than those required for clinical care. Follow-up and data collection are modeled after tumor registry procedures. Patients who refuse randomization enter the study in whichever treatment arm they choose. The protocol for each study is approved by the institutional review board (IRB) before recruitment begins, and all patients, randomized and nonrandomized, sign an informed consent document. Between its beginning on October 7, 1993 and April 7, 1997, the IRB approved 14 trials. Four were terminated after entering at most a few patients. Recruitment is complete in four trials and continues in six. Randomization was accepted by 74% (596/804) of the patients. Over 800 patients in 10 studies are being followed at least annually. Major peer-reviewed journals have accepted reports of initial findings for two studies. Prospective randomized effectiveness studies are feasible in the multipractice setting and have potential to provide useful and reliable assessment of treatment outcomes. Collaborative arrangements between several institutions are needed to provide larger sample sizes.
Asunto(s)
Evaluación de Resultado en la Atención de Salud , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Centros Médicos Académicos , Recolección de Datos , Estudios de Factibilidad , Estudios de Seguimiento , Práctica de Grupo , Sistemas Prepagos de Salud , Humanos , Consentimiento Informado , Estudios Longitudinales , Estudios Multicéntricos como Asunto , Atención al Paciente , Participación del Paciente , Selección de Paciente , Revisión de la Investigación por Pares , Comité de Profesionales , Estudios Prospectivos , Edición , Sistema de Registros , Reproducibilidad de los Resultados , Proyectos de Investigación , Tamaño de la Muestra , Resultado del TratamientoRESUMEN
UNLABELLED: Amrinone and milrinone are phosphodiesterase inhibitors with positive inotropic effects useful for the treatment of ventricular dysfunction after cardiac surgery. Forty-four patients undergoing elective cardiac surgery at four centers received either amrinone (n = 22) or milrinone (n = 22) in a randomized, blind fashion. Immediately after separation from cardiopulmonary bypass (CPB), two bolus doses of either amrinone 0.75 mg/kg or milrinone 25 microg/kg were administered over 30 s, separated by 5 min. Hemodynamic measurements were recorded before each dose and at the end of the 10-min study. Both amrinone and milrinone increased the cardiac index (48% vs 52%, P = not significant [NS] for amrinone and milrinone, respectively). There was a small increase in mean arterial pressure (MAP) after amrinone administration (from 68 +/- 3 to 72 +/- 3 mm Hg at 10 min, P < 0.05) with no significant change in MAP after milrinone administration. Central venous pressure was significantly higher in the amrinone group at baseline and 5 min (12 vs 10 mm Hg and 11 vs 10 mm Hg, respectively; P < 0.05). Systemic and pulmonary vascular resistances decreased significantly and to a similar extent after either amrinone or milrinone administration. Phenylephrine was required in 11 of 22 patients receiving amrinone and in 11 of 22 patients receiving milrinone to maintain arterial blood pressure. The proportion of patients requiring an intravascular volume infusion (15 of 22 vs 17 of 22, P = NS) and the total fluid volume infused were similar (402 +/- 57 vs 350 +/- 49 mL, P = NS for amrinone and milrinone, respectively). Amrinone and milrinone seem to have similar hemodynamic effects after CPB, with the exception of blood pressure, although the need for vasopressor support of blood pressure did not differ. Selection between these two drugs may include nonhemodynamic considerations such as cost. IMPLICATIONS: Amrinone and milrinone are drugs that improve cardiac contraction. Their effects have never been directly compared in patients. We found that amrinone and milrinone produced similar hemodynamic effects in adult patients undergoing cardiac surgery. Choice between the two drugs can be based on nonhemodynamic considerations such as cost.
Asunto(s)
Amrinona/uso terapéutico , Procedimientos Quirúrgicos Cardíacos , Cardiotónicos/uso terapéutico , Inhibidores de Fosfodiesterasa/uso terapéutico , Piridonas/uso terapéutico , Adulto , Anciano , Amrinona/administración & dosificación , Presión Sanguínea/efectos de los fármacos , Gasto Cardíaco/efectos de los fármacos , Puente Cardiopulmonar , Cardiotónicos/administración & dosificación , Presión Venosa Central/efectos de los fármacos , Costos de los Medicamentos , Procedimientos Quirúrgicos Electivos , Femenino , Fluidoterapia , Hemodinámica/efectos de los fármacos , Humanos , Inyecciones Intravenosas , Pulmón/irrigación sanguínea , Masculino , Persona de Mediana Edad , Milrinona , Contracción Miocárdica/efectos de los fármacos , Fenilefrina/uso terapéutico , Inhibidores de Fosfodiesterasa/administración & dosificación , Sustitutos del Plasma/uso terapéutico , Piridonas/administración & dosificación , Método Simple Ciego , Resistencia Vascular/efectos de los fármacos , Vasoconstrictores/uso terapéutico , Disfunción Ventricular/prevención & controlRESUMEN
OBJECTIVE: To determine whether postoperative forced-air warming of cardiac bypass patients in the intensive care unit (ICU) results in faster rate of warming and improved outcomes compared with more conventional ICU warming methods. DESIGN: Prospective randomized effectiveness study. SETTING: Three hundred fifty-bed university-affiliated hospital. PARTICIPANTS: Sixty consenting randomized patients from a consecutive series of 84 patients undergoing routine adult cardiac surgery. INTERVENTIONS: One group of patients received usual patient care, which includes warm blankets and overhead heat lamps. Patients in the other group were placed under forced-air warming devices on arrival in the ICU. Sixty consenting patients (30 in each group) were randomly assigned to one or the other method of warming. The remaining 24 patients refused randomization and self-selected a treatment group. MEASUREMENTS AND MAIN RESULTS: Results are presented for the randomized groups. Core temperature, measured by pulmonary artery catheter thermistor, increased in both groups at the rate of 0.25 degree C per hour. No statistically or clinically significant differences were found between the group for whom the warming device was used and the standard care group in the incidence of postoperative cardiac arrhythmia, duration of time in the ICU, or any other clinical variable. CONCLUSIONS: There is no evidence from this study to warrant use of forced-air warming devices for the care of postoperative cardiac surgical patients in the ICU.