Unreliable Tracking Ability of the Third-Generation FloTrac/Vigileo™ System for Changes in Stroke Volume after Fluid Administration in Patients with High Systemic Vascular Resistance during Laparoscopic Surgery

<div><p>Background</p><p>The FloTrac/Vigileo^™ system does not thoroughly reflect variable arterial tones, due to a lack of external calibration. The ability of this system to measure stroke volume and track its changes after fluid administration has not been fully evaluated in patients with the high systemic vascular resistance that can develop during laparoscopic surgery.</p><p>Methods</p><p>In 42 patients undergoing laparoscopic prostatectomy, the stroke volume derived by the third-generation FloTrac/Vigileo^™ system (SV-Vigileo), the stroke volume measured using transesophageal echocardiography (SV-TEE) as a reference method, and total systemic vascular resistance were evaluated before and after 500 ml fluid administration during pneumoperitoneum combined with the Trendelenburg position.</p><p>Results</p><p>Total systemic vascular resistance was 2159.4 ± 523.5 dyn·s/cm⁵ before fluid administration. The SV-Vigileo was significantly higher than the SV-TEE both before (68.8 ± 15.9 vs. 57.0 ± 11.0 ml, <i>P</i> < 0.001) and after (73.0 ± 14.8 vs. 64.9 ± 12.2 ml, <i>P</i> = 0.003) fluid administration. During pneumoperitoneum combined with the Trendelenburg position, Bland-Altman analysis for repeated measures showed a 53.8% of percentage error between the SV-Vigileo and the SV-TEE. Four-quadrant plot (69.2% of a concordance rate) and polar plot analysis (20.6° of a mean polar angle, 16.4° of the SD of a polar angle, and ±51.5° of a radial sector containing 95% of the data points) did not indicate a good trending ability of the FloTrac/Vigileo^™ system.</p><p>Conclusions</p><p>The third-generation FloTrac/Vigileo^™ system may not be useful in patients undergoing laparoscopic surgery, based on unreliable performance in measuring the stroke volume and in tracking changes in the stroke volume after fluid administration during pneumoperitoneum combined with the Trendelenburg position.</p></div

Comparison of acute kidney injury between open and laparoscopic liver resection: Propensity score analysis

<div><p>The inflammatory response has been shown to be a major contributor to acute kidney injury. Considering that laparoscopic surgery is beneficial in reducing the inflammatory response, we compared the incidence of postoperative acute kidney injury between laparoscopic liver resection and open liver resection. Among 1173 patients who underwent liver resection surgery, 222 of 926 patients who underwent open liver resection were matched with 222 of 247 patients who underwent laparoscopic liver resection, by using propensity score analysis. The incidence of postoperative acute kidney injury assessed according to the creatinine criteria of the Kidney Disease: Improving Global Outcomes definition was compared between those 1:1 matched groups. A total 77 (6.6%) cases of postoperative acute kidney injury occurred. Before matching, the incidence of acute kidney injury after laparoscopic liver resection was significantly lower than that after open liver resection [1.6% (4/247) vs. 7.9% (73/926), <i>P</i> < 0.001]. After 1:1 matching, the incidence of postoperative acute kidney injury was still significantly lower after laparoscopic liver resection than after open liver resection [1.8% (4/222) vs. 6.3% (14/222), <i>P</i> = 0.008; odds ratio 0.273, 95% confidence interval 0.088–0.842, <i>P</i> = 0.024]. The postoperative inflammatory marker was also lower in laparoscopic liver resection than in open liver resection in matched set data (white blood cell count 12.7 ± 4.0 × 10³/μL vs. 14.9 ± 3.9 × 10³/μL, <i>P</i> < 0.001). Our findings suggest that the laparoscopic technique, by decreasing the inflammatory response, may reduce the occurrence of postoperative acute kidney injury during liver resection surgery.</p></div

Comparison of perioperative inflammatory markers.

<p>Comparison of maximum neutrophil-to-lymphocyte ratio and white blood cell count within postoperative day 7 between laparoscopic and open liver resection (a, c) before and (b, d) after matching. In matched set data, white blood cell count was significantly lower in the LLR group during the first postoperative week. LLR, laparoscopic liver resection; OLR, open liver resection; WBC, white blood cell; POD, postoperative day.</p

Study flow diagram.

<p>Study flow diagram.</p

Comparison of postoperative acute kidney injury.

<p>The overall incidence of postoperative acute kidney injury was significantly lower after laparoscopic liver resection than after open liver resection. This result was consistent between (a) before and (b) after matching. LLR, laparoscopic liver resection; OLR, open liver resection.</p

Demographics and preoperative characteristics.

<p>Data are presented as mean ± SD or number (percentage).</p><p>Demographics and preoperative characteristics.</p

Patient demographics and perioperative variables before and after matching.

<p>Patient demographics and perioperative variables before and after matching.</p

Bland-Altman plot for the difference between the SV-TEE and the SV-Vigileo during pneumoperitoneum combined with the steep Trendelenburg position.

<p>SV-TEE, stroke volume measured using transesophageal echocardiography; SV-Vigileo, stroke volume derived by the third-generation FloTrac/Vigileo^™ system.</p

Survival curve according to the occurrence of postoperative AKI.

<p>Survival plot with Cox regression model demonstrated a significantly higher survival rate among patients with postoperative AKI (a) before (b) after matching. AKI, acute kidney injury.</p

Hemodynamic data at different time points.

<p>Data are presented as mean ± SD. T₀, after anesthetic induction in supine position; T₁, 3 minutes after the steep Trendelenburg position (35°) was added to pneumoperitoneum during which time insufflation pressure was set to 15 mmHg; T₂, 3 minutes after 500 ml of colloid infusion in T₁; SV-Vigileo, stroke volume derived by the FloTrac/Vigileo^™ system; SV-TEE, stroke volume measured using transesophageal echocardiography; MABP, mean arterial blood pressure; HR, heart rate; TSVR, total systemic vascular resistance; AC, arterial compliance.</p><p>*P < 0.05 vs T₀;</p><p>^† P < 0.05 vs T₁.</p><p>Hemodynamic data at different time points.</p