Clinical value of lung ultrasound in the late goal-directed fluid removal in critically ill patients underwent fluid resuscitation

Abstract

To investigate the clinical value of lung ultrasound in the late goal -directed fluid removal in critically ill patients underwent fluid resuscitation. A prospective study was conducted. Forty patients underwent fluid resuscitation were enrolled in the Department of Surgical Intensive Care Unit of The First Affiliated Hospital of Sun Yat-sen University from Jan 2015 to June 2015. Lung and heart ultrasound were conducted for lung B-lines and left ventricular ejection fraction (EF). Serum amino-terminal pro-brain natriuretic peptide (NT-proBNP), central venous pressure (CVP) and serum creatinine were also measured and fluid balance was recorded in all patients enrolled. Among the 40 patients enrolled, 35 patients survived and 5 died. In patients survived, B-lines reached its peak at 12(30)h after admitted to ICU. It started to decrease instantly after the peak and reached zero at (39±34) h. A higher peak was followed with more fluids to be removed later and longer ICU stay (P<0.01). Moreover, when compared with the survivors, B-lines in death reached a higher peak[7(8) vs 3(4), P<0.01]and without the tendency to drop down. EF was lower in death than in survivor (44.5%±3.5% vs 69.2%±11.0%, P<0.05). A lower EF was found to be followed with a higher peak of B-lines. The peak time of NT-proBNP and clinical dehydration treatment were later than the peak time of B-lines in survivors. Fluid overloading occurs in late stage after resuscitation in critically ill patients. Lung ultrasound B-lines, which is more sensitive than the NT-proBNP and CVP, could help to monitor the patient's fluid status and guide the late goal-directed fluid removal.