Point-of-care ultrasound na avaliação da congestão pulmonar no pós-operatório de cirurgia cardíaca: um estudo de acurácia diagnóstica na prática da enfermagem

Abstract

ntroduction: Pulmonary congestion is a frequent condition in the postoperative period of cardiac surgery and may be present even in the absence of overt clinical signs. Although the Clinical Congestion Score (CCS) is widely used in routine care, its ability to detect early congestion is limited, particularly in hemodynamically complex patients. In this context, point-of-care ultrasound (POCUS) has emerged as a valuable tool for identifying subclinical pulmonary congestion through the Lung Ultrasound Score (LUS) and inferior vena cava (IVC) assessment, potentially enhancing the accuracy of nursing clinical evaluation. Objective: To evaluate the diagnostic accuracy and clinical applicability of POCUS in detecting pulmonary congestion in the postoperative period of cardiac surgery, compared with traditional clinical assessment. Methods: This prospective cohort study was conducted in accordance with the STROBE (Strengthening the Reporting of Observational studies in Epidemiology) guidelines and included patients in the postoperative period of cardiac surgery. Sociodemographic and clinical data were collected, and congestion was assessed using the CCS and pulmonary and IVC POCUS. Clinical, hemodynamic, and in-hospital outcomes were compared between patients with and without pulmonary congestion. Results: Ultrasound assessment identified pulmonary congestion in 84.9% of patients, whereas the CCS classified 31.4% as congested. Among patients with POCUS-detected congestion, 65.8% presented mild congestion and 34.2% moderate congestion; no cases of severe congestion were identified, and all patients classified as non-congested by POCUS showed normal LUS findings. Clinical congestion assessed by the CCS was associated with greater systemic severity, with the SOFA score remaining the only independently associated factor in multivariable analysis (p < 0.05). Regarding congestion detected by POCUS, lower urine output was the only associated variable, with no significant associations with mechanical ventilation, intensive care unit length of stay, total hospital length of stay, or mortality. The area under the curve (AUC) was 0.527 (95% CI: 0.332–0.721), indicating low discriminatory capacity of the clinical score to identify pulmonary congestion when compared to the ultrasound method. Conclusion: POCUS demonstrated superior diagnostic capacity for detecting pulmonary congestion compared with traditional clinical assessment, enabling the identification of subclinical congestion in the postoperative period of cardiac surgery. These findings support the role of POCUS as a complementary tool to clinical evaluation, enhancing diagnostic accuracy and strengthening nursing practice in critical care settings.