Paiva Filho Odilar de, Braz José Reinaldo Cerqueira, Silva Fredson de Paula E, Pedro Tiago Otávio, Nascimento Júnior Paulo do
Universidade Estadual Paulista, Brazil.
Rev Bras Anestesiol. 2003 Jun;53(3):361-76. doi: 10.1590/s0034-70942003000300007.
Studies have introduced a new method for preload evaluation based on systolic pressure variation analysis (SPV) during mechanical ventilation. This research aimed at evaluating whether SPV and its delta down derived (ddown) are earlier hypovolemia indicators and guides for volume replacement with hypertonic and hyperoncotic solutions.
Twelve dogs were submitted to graded hemorrhage of 5% of their volume until reaching 20% of volume (14 ml.kg-1). Before (control) and after every hemorrhage, hemodynamic, ventilatory and blood parameters were evaluated. Then, dogs were submitted to volume replacement with 7.5% NaCl in 3.75% dextran 70 (SHD) (4 ml.kg-1), and the parameters were again evaluated 5 and 30 minutes after volume replacement.
Mean blood pressure decreased during hemorrhage and increased after SHD infusion, however without returning to baseline values. Right atrium (RAP) and pulmonary artery pressure (PAP) decreased before and increased after volume replacement reaching values similar to baseline. Pulmonary capillary wedge pressure (PCWP) decreased after the first hemorrhage and remained below baseline values even after volume replacement. Cardiac index has not changed, but increased after SHD infusion reaching values above baseline. Stroke volume index (SVI) decreased before, and increased after volume replacement reaching values above baseline. Systemic vascular and pulmonary resistance did not change during hemorrhage, but decreased after volume replacement, with SVRI remaining below baseline values and SVPRI in levels similar to baseline. Left ventricular stroke work index (LVSWI) and right ventricular stroke work index (RVSWI) decreased before and increased after SHD infusion, with RVSWI remaining above baseline values and LVSWI in levels similar to baseline. SPV and ddown progressively increased during hemorrhage and decreased after volume replacement, however remaining above baseline values. Major SPV and ddown correlations were found with SVI, PWCP, RAP, PAP and LVSWI.
In dogs under our experimental conditions, SPV and its derived ddown are early hypovolemia indicators and sensitive guides for volume replacement with hypertonic and hyperoncotic solutions.
多项研究引入了一种基于机械通气期间收缩压变异分析（SPV）的前负荷评估新方法。本研究旨在评估SPV及其衍生的向下差值（ddown）是否为早期低血容量指标以及高渗和高渗胶体溶液容量替代的指导指标。
12只犬接受相当于其血容量5%的分级出血，直至达到血容量的20%（14 ml·kg⁻¹）。在每次出血前（对照）和出血后，评估血流动力学、通气和血液参数。然后，给犬输注7.5%氯化钠与3.75%右旋糖酐70混合液（SHD）进行容量替代（4 ml·kg⁻¹），并在容量替代后5分钟和30分钟再次评估参数。
出血期间平均血压下降，SHD输注后升高，但未恢复至基线值。右心房压（RAP）和肺动脉压（PAP）在容量替代前下降，替代后升高至接近基线值。首次出血后肺毛细血管楔压（PCWP）下降，即使在容量替代后仍低于基线值。心脏指数未改变，但SHD输注后升高至高于基线值。每搏量指数（SVI）在容量替代前下降，替代后升高至高于基线值。全身血管阻力和肺血管阻力在出血期间未改变，但在容量替代后下降，全身血管阻力指数（SVRI）仍低于基线值，肺血管阻力指数（SVPRI）处于接近基线水平。左心室每搏功指数（LVSWI）和右心室每搏功指数（RVSWI）在SHD输注前下降，输注后升高，RVSWI仍高于基线值，LVSWI处于接近基线水平。SPV和ddown在出血期间逐渐升高，容量替代后下降，但仍高于基线值。发现SPV和ddown与SVI、PWCP、RAP、PAP和LVSWI存在主要相关性。
在我们的实验条件下，犬的SPV及其衍生的ddown是早期低血容量指标以及高渗和高渗胶体溶液容量替代的敏感指导指标。
