Correlação entre variáveis clínicas e a variação da espessura dos músculos diafragma e quadríceps em pacientes criticamente doentes

Abstract

Introduction: Critically ill patients have an imminent risk of death caused by a serious injury situation. Trauma is a common cause of admission at intensive care units (ICU). Critically ill trauma patients develop a complex pathophysiological response defined conceptually as Systemic Inflammatory Response Syndrome (SIRS). The main pathophysiological changes in SIRS are metabolic, hormonal, inflammatory, immunological and circulatory changes. The pathophysiological changes in SIRS modify the body composition, with emphases on acute and marked depletion of muscle mass. The assessment of risk and nutritional status are essential for preventing the development / worsening of malnutrition in critically ill patients with emphasis on the assessment of body composition. Objectives: Evaluate the associations between the variation in the thickness of the diaphragm muscle using ultrasound with the nutritional risk, and with the mortality rate, in critically ill trauma patients submitted to mechanical ventilation (MV). Material and Methods: Prospective, observational study, developed in an ICU, tertiary-level public university hospital. Patients: Male, in critical condition after exposure to trauma, age ≥18 years and <60 years, on MV for at least 5 days. Interventions: C-reactive protein (CRP); scores Acute Physiology and Chronic Health Evaluation II (APACHE II); Simplified Acute Physiology Score 3 (SAPS 3); Sequential Organ Failure Assessment (SOFA); and modified Nutrition Risk in the Critically Ill (mNUTRIC); Charlson's Comorbidity Index; hospital and ICU length stay; MV period; extubation failure; ventilatory parameters; and clinical evolution (hospital discharge / death) were the parameters evaluated. The diaphragm thickening fraction (DTF) was identified by the difference between the thickness of the diaphragm at the end of inspiration and exhalation, divided by the thickness at the end of exhalation, multiplied by 100. The evaluation of the sectional area of the rectus femoris muscle by ultrasound was performed directly by measuring a cross-section at the midpoint of the muscle. Results: The evaluated patients (n = 44) had a mean age of 37.1 ± 11.4 years, failure to wean from MV of 15.9% (n = 7) and mortality rate of 18.2% (n = 8). Non-surviving patients had higher values for CRP (p = 0.007), SAPS 3 (p = 0.001), SOFA (p = 0.031), and MV period (p <0.001). In the analysis of the variation in DTF between measures 2 (5-7 days of hospitalization) and 1 (0-2 days of hospitalization) it was shown that DTF increased and decreased for non-survivors and survivors, respectively (p = 0.038). The variation in DTF showed a strong positive correlation (r = 0.810) and a negligible negative correlation (r = -0.163) with the variation in CRP for non-survivors and survivors, respectively. DTF (p = 0.042), MV period (p = 0.013), and mNUTRIC score (p = 0.042) were predictors of hospital mortality. In the analysis of the measurements of the variation of the sectional area of the rectus femoris muscle, no statistical difference was identified. Conclusion: The increase in DTF and nutritional risk have a predictive value for mortality. The variation in DTF during the first week of hospitalization is a useful parameter for assessing the prognosis of critically ill patients on MV.