Department of Anaesthesiology, Government Medical College, Patiala, Punjab, India.
Department of Cardiac Anaesthesia, Sri Jayadeva Institute of Cardiovascular Sciences and Research, Bangalore, Karnataka, India.
Ann Card Anaesth. 2020 Oct-Dec;23(4):429-432. doi: 10.4103/aca.ACA_137_19.
Intra and postoperative perfusion monitoring should be used in critical limb ischemia patients undergoing vascular surgery to improve outcomes and reduce costs. While a pulse oximeter can be applied on the affected limb to monitor the arterial saturation of the limb, thus reflecting flow in that limb, we need to focus on other important parameters like muscle oxygen consumption and regional blood flow for a good outcome. Near-infrared spectroscopy (NIRS) can be used in such patients to monitor regional and tissue oxygenation.
In this prospective observational study, 30 adult patients undergoing infra-inguinal bypass were recruited. All these patients were given combined spinal-epidural anesthesia. In addition to routine monitoring, a pulse oximeter and NIRS electrodes were applied on the affected limb. rsO2, limb spO2, and Doppler signals were noted before the induction of anesthesia (baseline) and postoperatively at 0, 6, and 12 h. Improvement in rsO2 and limb spO2 values after surgery was noted and fall in these values was evaluated. Pearson correlation between rsO2 and limb spO2 was assessed. The data was analyzed using repeated-measures ANOVA.
Pearson correlation between rsO2 and limb spO2 was r > 0.8. Two patients had a fall in rsO2 in postoperative period, which co-related with a fall in limb spO2 and decreased/absent Doppler signals.
NIRS represents a noninvasive and reliable means to monitor limb perfusion in patients undergoing vascular surgery for rest pain.
在接受血管手术的严重肢体缺血患者中，应使用术中及术后灌注监测来改善结果并降低成本。脉搏血氧仪可应用于受影响的肢体以监测肢体的动脉饱和度，从而反映该肢体的血流，但我们还需要关注其他重要参数，如肌肉耗氧量和局部血流量，以获得良好的结果。近红外光谱（NIRS）可用于监测此类患者的局部和组织氧合。
在这项前瞻性观察研究中，招募了 30 名接受下肢旁路手术的成年患者。所有这些患者均接受了脊髓-硬膜外联合麻醉。除了常规监测外，还在受影响的肢体上应用脉搏血氧仪和 NIRS 电极。记录麻醉诱导前（基线）和术后 0、6 和 12 小时的 rsO2、肢体 SpO2 和多普勒信号。记录术后 rsO2 和肢体 SpO2 值的改善情况，并评估这些值的下降情况。评估 rsO2 和肢体 SpO2 之间的 Pearson 相关性。使用重复测量方差分析对数据进行分析。
rsO2 和肢体 SpO2 之间的 Pearson 相关性为 r > 0.8。术后有 2 例患者 rsO2 下降，与肢体 SpO2 下降和多普勒信号减少/消失相关。
NIRS 是监测血管外科手术治疗静息痛患者肢体灌注的一种非侵入性和可靠的方法。
