Diagnostic accuracy of a calibrated abdominal compression to predict fluid responsiveness in children.

BACKGROUND: Fluid administration to increase stroke volume index (SVi) is a cornerstone of haemodynamic resuscitation. We assessed the accuracy of SVi variation during a calibrated abdominal compression manoeuvre (ΔSVi-CAC) to predict fluid responsiveness in children. METHODS: Patients younger than 8 yr with acute circulatory failure, regardless of their ventilation status, were selected. SVi, calculated as the average of five velocity-time integrals multiplied by the left ventricular outflow tract surface area, was recorded at four different steps: baseline, after an abdominal compression with a calibrated pressure of 25 mm Hg, after return to baseline, and then after a volume expansion (VE) of 10 ml kg-1 lactated Ringer solution over 10 min. Patients were classified as responders if SVi variation after volume expansion (ΔSVi-VE) increased by at least 15%. RESULTS: The 39 children included had a median [inter-quartile range (IQR)] age of 9 [5-31] months. Twenty patients were fluid responders and 19 were non-responders. ΔSVi-CAC correlated with ΔSVi-VE (r=0.829; P<0.001). The area under the receiver operating characteristic curve (ROCAUC) was 0.94 [95% confidence interval (CI), 0.85-0.99]. The best threshold for ΔSVi-CAC was 11% with a specificity of 95% [95% CI, 84-100] and a sensitivity of 75% [95% CI, 55-95]. ROCAUC of respiratory variation of IVC diameter (ΔIVC) was 0.53 [95% CI, 0.32-0.72]. CONCLUSION: ΔSVi-CAC during abdominal compression was a reliable method to predict fluid responsiveness in children with acute circulatory failure regardless of their ventilation status. CLINICAL TRIALS REGISTRATION: CPP Lyon sud est II: n° ANSM 2015-A00388-41 Clinicaltrial.gov: NCT02505646.

Renal haemodynamic response to amino acids infusion in an experimental porcine model of septic shock.

BACKGROUND: Acute kidney injury (AKI) is common in sepsis. Treatments allowing maintenance of renal blood flow (RBF) could help to prevent AKI associated with renal hypoperfusion. Amino acids (AA) have been associated with an increase of RBF and glomerular filtration rate (GFR) in several species. The aim of this study was to evaluate the effects of an AA infusion on RBF and GFR in a porcine model of septic shock. METHODS: A total of 17 piglets were randomly assigned into three groups: Sham (Sham, n = 5), sepsis without AA (S-NAA, n = 6), sepsis treated with AA (S-AA, n = 6). Piglets preparation included the placement of ultrasonic transit time flow probes around left renal artery for continuous RBF measurement; ureteral catheters for GFR and urine output evaluation; pulmonary artery catheter for cardiac output (CO) and pulmonary arterial pressure measurements. Mean arterial pressure (MAP) and renal vascular resistance (RVR) were also determined. Septic shock was induced with a live Pseudomonas aeruginosa infusion. Crystalloids, colloids and epinephrine infusion were used to maintain and restore MAP > 60 mmHg and CO > 80% from baseline. RESULTS: Renal haemodynamic did not change significantly in the Sham group, whereas RBF increased slightly in the S-NAA group. Conversely, a significant increase in RVR and a decrease in RBF and GFR were observed in the S-AA group. AA infusion was associated with a higher requirement of epinephrine [340.0 (141.2; 542.5) mg vs. 32.5 (3.8; 65.0) mg in the S-NAA group P = 0.044]. CONCLUSION: An infusion of amino acids impaired renal haemodynamics in this experimental model of septic shock.