Arterial Pressure Variation in Elective Noncardiac Surgery: Identifying Reference Distributions and Modifying Factors

Abstract

Background Assessment of need for intravascular volume resuscitation remains challenging for anesthesiologists. Dynamic waveform indices, including systolic and pulse pressure variation, are demonstrated as reliable measures of fluid responsiveness for mechanically ventilated patients. Despite widespread use, real-world reference distributions for systolic and pulse pressure variation values have not been established for euvolemic intraoperative patients. The authors sought to establish systolic and pulse pressure variation reference distributions and assess the impact of modifying factors. Methods The authors evaluated adult patients undergoing general anesthetics for elective noncardiac surgery. Median systolic and pulse pressure variations during a 50-min postinduction period were noted for each case. Modifying factors including body mass index, age, ventilator settings, positioning, and hemodynamic management were studied via univariate and multivariable analyses. For systolic pressure variation values, effects of data entry method (manually entered vs. automated recorded) were similarly studied. Results Among 1,791 cases, per-case median systolic and pulse pressure variation values formed nonparametric distributions. For each distribution, median values, interquartile ranges, and reference intervals (2.5th to 97.5th percentile) were, respectively, noted: these included manually entered systolic pressure variation (6.0, 5.0 to 7.0, and 3.0 to 11.0 mmHg), automated systolic pressure variation (4.7, 3.9 to 6.0, and 2.2 to 10.4 mmHg), and automated pulse pressure variation (7.0, 5.0 to 9.0, and 2.0 to 16.0%). Nonsupine positioning and preoperative β blocker were independently associated with altered systolic and pulse pressure variations, whereas ventilator tidal volume more than 8 ml/kg ideal body weight and peak inspiratory pressure more than 16 cm H2O demonstrated independent associations for systolic pressure variation only. Conclusions This study establishes real-world systolic and pulse pressure variation reference distributions absent in the current literature. Through a consideration of reference distributions and modifying factors, the authors’ study provides further evidence for assessing intraoperative volume status and fluid management therapies.

Comparison of Dynamic Measures in Intraoperative Goal-Directed Fluid Therapy of Patients with Morbid Obesity Undergoing Laparoscopic Sleeve Gastrectomy

“…Although the dynamic parameters differed in our study, a similar protocol was used in the patients. Our study used a threshold of 13% for PVI-directed fluid therapy, 10 mmHg for SPV-directed fluid therapy, and 13% for PPV-directed fluid therapy under the thresholds used in the literature [ 11 , 27 ].…”

Intraoperative Hemodynamic Fluid Therapy for Immediate- to Highrisk Non-cardiac Surgery: A Narrative Review

“…25 The evaluation of patients in the Trendelenburg position in robot-assisted laparoscopic surgery has shown the tidal volume challenge test to be reliable, and the reliability of this test was even confirmed in neurosurgical patients in the prone position; however, evaluations involving patients in the extreme Trendelenburg position are quite limited. 31,32 Continuous CO monitoring based on calibrated and a non-calibrated pulse-wave analysis has been developed to facilitate the co-evaluation of fluid responsiveness with tests such as the passive leg rising test (PLRT), endexpiratory occlusion test (EEOT), and mini-fluid challenge test. PLRT has an autotransfusion of approximately 300 mL of blood and is accurate in conditions involving an increased CO of more of than 10.0% (sensitivity, 86.0%; specificity, 92.0%).…”

Fluid management concepts for severe neurological illness

“…Arterial pulse pressure variation (PPV) is a promising predictor of fluid responsiveness, though its interpretation has so far been validated in patients who are mechanically ventilated with positive pressure, in sinus rhythm, at tidal volumes of at least 8 ml/kg, and closed chests [2]. Recent work quantifying the natural distribution of PPV provides a valuable starting point for evaluating PPV as an index of volume status and predictor of fluid response [3]. The value of PPV-guided therapy is strongly suggested in an observational study of acute SAH patients by Drevet et al (2017), wherein a restrictive fluid management protocol guided by PPV and CVP resulted in fewer hypoxemic episodes versus weight-based liberal fluid management.…”