RESUMO
OBJECTIVE: To study the ability of the urea/creatinine index to identify severe protein catabolism from the isolated urine of critically ventilated patients. METHODS: This was a prospective, observational study. It included 52 patients without kidney failure. Variables: total urinary nitrogen estimated from the urea in 24-hour urine on the second (T1) and fourth days (T2) and urea/creatinine index in isolated urine before 24-hour urine collection. RESULTS: Severe protein hypercatabolism (estimated total urinary nitrogen > 15g) was present in 14 patients (26.9%) at T1 and in 29 (55.7%) at T2. Eighty-four percent of patients had low nutritional risk by the Nutrition Risk in the Critically Ill score. At T1, the Pearson correlation between the estimated total urinary nitrogen and the urea/creatinine index was 0.272 (p = 0.051), and at T2 it was 0.276 (p = 0.048). The urea/creatinine index at T2 had a tendency to better discriminate severe protein hypercatabolism than Acute Physiology and Chronic Health Evaluation II and Nutrition Risk in the Critically Ill (AUC 0.741 versus 0.669 and 0.656, 95%CI: 0.602 - 0.880; 0.519 - 0.818 and 0.506 - 0.806, respectively). The optimal cutoff value of the urea/creatinine index for the diagnosis of severe protein hypercatabolism was 16.15, with a sensitivity of 79.31% (95%CI: 59.74 - 91.29), specificity of 60.87% (95%CI: 38.78 - 79.53), positive predictive value 71.88% (95%CI: 53.02 - 85.60), negative predictive value 70.0% (95%CI: 45.67 - 87.18), LR (+) 2.03 (95%CI: 1.18 - 3.49), and LR (-) 0.34 (95%CI: 0.16 - 0.74). CONCLUSION: The urea/creatinine index measured on the fourth day has a certain ability to estimate severe protein hypercatabolism (as defined by estimated total urinary nitrogen) but does not replace total urinary nitrogen in critically ventilated patients without kidney failure. Due to its reasonable sensitivity, it could be used as a screen to identify which patients to take a 24-hour urine sample from.
OBJETIVO: Estudiar la capacidad discriminativa de hipercatabolismo proteico grave del índice urea/creatinina en orina aislada en pacientes críticos ventilados. METODOS: Estudio prospectivo, observacional. Incluyó 52 pacientes sin insuficiencia renal. Variables: nitrógeno urinario total estimado a partir de la urea en orina de 24 horas al segundo (T1) y cuarto día (T2) e índice urea/creatinina en orina aislada previo a la recolección de orina de 24 horas. RESULTADOS: Presentaron hipercatabolismo proteico grave (nitrógeno urinario total estimado > 15g) 14 pacientes (26,9%) en T1 y 29 (55,7%) en T2. El 84% de los pacientes presentaron bajo riesgo nutricional por la escala Nutrition Risk in the Critically Ill. En el segundo día, la correlación de Pearson del nitrógeno urinario total estimado con el índice urea/creatinina fue: 0,272 (p = 0,051) y en el cuarto día: 0,276 (p = 0,048). El índice urea/creatinina al cuarto día, tuvo una tendencia a mayor discriminación del hipercatabolismo proteico grave que el Acute Physiology and Chronic Health Evaluation II y Nutrition Risk in the Critically Ill (AUC 0,741 versus 0,669 y 0,656, IC95%: 0,602 - 0,880; 0,519 - 0,818 y 0,506 - 0,806 respectivamente). El valor de corte optimo del índice urea/creatinina para diagnóstico de hipercatabolismo proteico grave fue de 16,15 con una sensibilidad de 79,31% (IC95%: 59,74 - 91,29), especificidad de 60,87% (IC95%: 38,78 - 79,53), valor predictivo positivo 71,88% (IC95%: 53,02 - 85,60), valor predictivo negativo 70,0% (IC95%: 45,67 - 87,18), LR (+) 2,03 (IC95%: 1,18 - 3,49) y LR (-) 0,34 (IC95%: 0,16 - 0,74). CONCLUSIÓN: El índice urea/creatinina realizado al cuarto día tiene un discreto valor para estimar el hipercatabolismo proteico grave por nitrógeno urinario total y no reemplaza al mismo en pacientes críticos ventilados sin falla renal. Por su razonable sensibilidad podría ser utilizado como cribado para identificar a quien tomar la muestra de orina de 24 horas.
Assuntos
Estado Terminal , Respiração Artificial , Creatinina , Humanos , Estudos Prospectivos , UreiaRESUMO
BACKGROUND AND OBJECTIVE: Procalcitonin (PCT) can help the early diagnosis of bacterial infections and estimate the response obtained. The objective is to study the value of PCT for the diagnosis of ventilator-associated pneumonia (VAP). PATIENTS AND METHOD: Prospective and observational study, carried out for 18 months, in a polyvalent Intensive Care Unit (ICU). Those included were over 18 years of age, with suspected pneumonia after 48h of mechanical ventilation (MV). Collected were demographic characteristics; admission pathology; reason for beginning MV; gravity scores (APACHE II, SAPS II and SOFA); C-reactive protein (CRP) and PCT. At the time of suspicion of VAP: early or late, radiological severity, presence of septic shock, SOFA, CRP, PCT and microbiology. RESULTS: Ninety-one patients with suspected VAP were included. The mean age was 42 (17.76) and that of hospitalisation in the ICU was 18.59 (11.69) days. VAP was confirmed in 74 patients, of which 19 (25.7%) presented septic shock. The mortality was 28.4%. There were no significant differences of the PCT in the patients who presented VAP versus those who did not present VAP (P=.449). When patients without VAP, with VAP and VAP with shock, were compared, the PCT median was 0.38 (CI95%: 0.22-1.90), 0.56 (CI95%: 0.19-1.77) and 1.93 (CI95%: 0.38-10.07), respectively (P=.169). CONCLUSIONS: In our study, PCT did not prove useful for the diagnosis of VAP.
Assuntos
Pneumonia Associada à Ventilação Mecânica/sangue , Pneumonia Associada à Ventilação Mecânica/diagnóstico , Pró-Calcitonina/sangue , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos ProspectivosAssuntos
Proteína C-Reativa , Desnutrição , Estado Terminal/mortalidade , Humanos , Avaliação NutricionalRESUMO
RESUMEN Objetivo: Estudiar la capacidad discriminativa de hipercatabolismo proteico grave del índice urea/creatinina en orina aislada en pacientes críticos ventilados. Metodos: Estudio prospectivo, observacional. Incluyó 52 pacientes sin insuficiencia renal. Variables: nitrógeno urinario total estimado a partir de la urea en orina de 24 horas al segundo (T1) y cuarto día (T2) e índice urea/creatinina en orina aislada previo a la recolección de orina de 24 horas. Resultados: Presentaron hipercatabolismo proteico grave (nitrógeno urinario total estimado > 15g) 14 pacientes (26,9%) en T1 y 29 (55,7%) en T2. El 84% de los pacientes presentaron bajo riesgo nutricional por la escala Nutrition Risk in the Critically Ill. En el segundo día, la correlación de Pearson del nitrógeno urinario total estimado con el índice urea/creatinina fue: 0,272 (p = 0,051) y en el cuarto día: 0,276 (p = 0,048). El índice urea/creatinina al cuarto día, tuvo una tendencia a mayor discriminación del hipercatabolismo proteico grave que el Acute Physiology and Chronic Health Evaluation II y Nutrition Risk in the Critically Ill (AUC 0,741 versus 0,669 y 0,656, IC95%: 0,602 - 0,880; 0,519 - 0,818 y 0,506 - 0,806 respectivamente). El valor de corte optimo del índice urea/creatinina para diagnóstico de hipercatabolismo proteico grave fue de 16,15 con una sensibilidad de 79,31% (IC95%: 59,74 - 91,29), especificidad de 60,87% (IC95%: 38,78 - 79,53), valor predictivo positivo 71,88% (IC95%: 53,02 - 85,60), valor predictivo negativo 70,0% (IC95%: 45,67 - 87,18), LR (+) 2,03 (IC95%: 1,18 - 3,49) y LR (-) 0,34 (IC95%: 0,16 - 0,74). Conclusión: El índice urea/creatinina realizado al cuarto día tiene un discreto valor para estimar el hipercatabolismo proteico grave por nitrógeno urinario total y no reemplaza al mismo en pacientes críticos ventilados sin falla renal. Por su razonable sensibilidad podría ser utilizado como cribado para identificar a quien tomar la muestra de orina de 24 horas.
ABSTRACT Objective: To study the ability of the urea/creatinine index to identify severe protein catabolism from the isolated urine of critically ventilated patients. Methods: This was a prospective, observational study. It included 52 patients without kidney failure. Variables: total urinary nitrogen estimated from the urea in 24-hour urine on the second (T1) and fourth days (T2) and urea/creatinine index in isolated urine before 24-hour urine collection. Results: Severe protein hypercatabolism (estimated total urinary nitrogen > 15g) was present in 14 patients (26.9%) at T1 and in 29 (55.7%) at T2. Eighty-four percent of patients had low nutritional risk by the Nutrition Risk in the Critically Ill score. At T1, the Pearson correlation between the estimated total urinary nitrogen and the urea/creatinine index was 0.272 (p = 0.051), and at T2 it was 0.276 (p = 0.048). The urea/creatinine index at T2 had a tendency to better discriminate severe protein hypercatabolism than Acute Physiology and Chronic Health Evaluation II and Nutrition Risk in the Critically Ill (AUC 0.741 versus 0.669 and 0.656, 95%CI: 0.602 - 0.880; 0.519 - 0.818 and 0.506 - 0.806, respectively). The optimal cutoff value of the urea/creatinine index for the diagnosis of severe protein hypercatabolism was 16.15, with a sensitivity of 79.31% (95%CI: 59.74 - 91.29), specificity of 60.87% (95%CI: 38.78 - 79.53), positive predictive value 71.88% (95%CI: 53.02 - 85.60), negative predictive value 70.0% (95%CI: 45.67 - 87.18), LR (+) 2.03 (95%CI: 1.18 - 3.49), and LR (-) 0.34 (95%CI: 0.16 - 0.74). Conclusion: The urea/creatinine index measured on the fourth day has a certain ability to estimate severe protein hypercatabolism (as defined by estimated total urinary nitrogen) but does not replace total urinary nitrogen in critically ventilated patients without kidney failure. Due to its reasonable sensitivity, it could be used as a screen to identify which patients to take a 24-hour urine sample from.