Usefulness of stroke volume variation to assess blood volume during blood removal for autologous blood transfusion in pediatric patients.

BACKGROUND: Dynamic variables based on the heart-lung interaction induced by positive pressure ventilation have not been shown to be useful in assessing cardiac preload in pediatric patients. OBJECTIVE: To evaluate whether stroke volume variation (SVV) obtained from the FloTrac/Vigileo(TM) monitoring system can reflect a change in blood volume during the blood removal and fluid replacement protocol in acute normovolemic hemodilution (ANH). METHODS: Sixteen pediatric patients scheduled for elective cranioplasty were recruited. In the ANH protocol, 10 ml · kg(-1) blood removal and fluid replacement were performed. SVV, heart rate, mean blood pressure, and femoral venous pressure were recorded. Differences at four time points (T0: baseline, T1: 5 ml · kg(-1) blood loss, T2: 10 ml · kg(-1) blood loss, and T3: after fluid replacement) during ANH were compared. The blood volume (EBV) was estimated as 70 ml · kg(-1) at T0 and decreased to 60 ml · kg(-1) at T2. RESULTS: Of the 16 patients, four were excluded and 12 were analyzed. Significant differences in all of the parameters were observed between each time point. The SVV significantly increased after the blood removal and decreased after the fluid replacement (P < 0.01, Bonferroni adjustment). In addition, the increases in SVV during the blood removal, T0-T1 and T0-T2, were 70% ± 40% and 159% ± 91%, respectively. SVV showed a significant correlation with EBV during the blood removal in ANH (rs = -0.68, 95% confidence interval -0.73 to -0.63, P < 0.001). CONCLUSION: Stroke volume variation obtained from the FloTrac/Vigileo(TM) monitoring system revealed a strong correlation with EBV during ANH without surgical stimulation. The usefulness of this device as an indicator of cardiac preload under hypovolemic or normovolemic conditions in children during surgery remains to be determined.

[Anesthetic management of patients with placenta previa accreta for cesarean section: a 7-year single-center experience].

BACKGROUND: Anesthetic management for cesarean section of patients with placenta previa accreta is challenging. The aim of this retrospective study was to review past placenta previa accreta cases in our hospital to propose a better strategy for anesthetic management for this difficult condition. METHODS: Cases of placenta previa accreta were identified in our anesthesia database. The diagnosis, surgical procedure, amount of blood loss and anesthetic management were reviewed. RESULTS: Eight cases of placenta previa accreta were identified. Four of the eight cases underwent stepwise treatment, and in one of the four cases, intra-aortic balloon occlusion (IABO) was performed. The amount of blood loss in the four cases ranged from 840 to 1,150 ml. The remaining four cases underwent cesarean hysterectomy. The amount of blood loss in the four cases ranged from 2,400 to 5,200 ml. Neuraxial anesthesia alone was planned in four cases, but in two of which anesthesia was converted to general anesthesia due to massive bleeding. CONCLUSIONS: The present retrospective study showed that stepwise treatment and using IABO could be an effective aid for management of plasenta previa accreta. It is necessary to compare the effectiveness of IABO with that of common iliac artery occlusion in reducing the amount of blood loss.

The three-step method for ultrasound-guided pediatric internal jugular venous catheterization: a clinical trial.

Ultrasound guidance may be a valuable adjunct for pediatric internal jugular vein catheterization. We previously reported a long-axis in plane technique, called the "three-step method", resulting in high success and a low complication rate by novice operators in adult patients. This is the first report of ultrasound-guided internal jugular vein catheterization (US-IJV) using the three-step method in pediatric patients. Fourteen junior residents underwent simulation training, and then participated in a clinical trial. They performed US-IJV in 14 pediatric patients with congenital heart disease before undergoing cardiac surgery under supervision of an experienced clinician. The overall success rate was 93 %, and all catheterizations were performed within two venipunctures. There were no complications associated with the procedure. The three-step method may facilitate pediatric US-IJV even by a novice operator during their first experience.