Section of Vascular Surgery, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden; Centre for Research and Development, Uppsala University/County Council of Gävleborg, Gävle, Sweden.
Section of Vascular Surgery, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden; Centre for Research and Development, Uppsala University/County Council of Gävleborg, Gävle, Sweden.
J Vasc Surg. 2021 Jul;74(1):97-104. doi: 10.1016/j.jvs.2020.11.035. Epub 2020 Dec 8.
Colonic ischemia (CI) is a life-threatening complication after aortic surgery. Postoperative surveillance of colonic perfusion might be warranted. The aim of the present study was to evaluate the safety and feasibility of postoperative extraluminal pH measurement (pHe) using colonic tonometry after open abdominal aortic aneurysm (AAA) repair.
Before closing the abdomen after open AAA repair, a tonometric catheter was placed transabdominally in contact with the sigmoid colon serosa, similar to a drainage catheter. Extraluminal partial pressure of carbon dioxide was measured postoperatively and combined with arterial blood gas analysis to calculate the pHe. The measurements were repeated every 4 hours with simultaneous intra-abdominal pressure measurements. The threshold for colonic malperfusion was set at pHe <7.2.
A total of 27 patients were monitored, 12 had undergone surgery for ruptured AAAs and 15 for intact AAAs. Of the 27 patients, 4 developed clinically significant CI requiring surgery. All four cases were preceded by a prolonged (>5 hours) pHe <7.2 indicating malperfusion. A fifth patient, who, during monitoring, had had the lowest pHe of 7.21, developed mild CI with the onset after completion of monitoring, which was successfully managed conservatively. Seven patients who had had brief durations (<5 hours) of pHe <7.2 did not develop clinical signs of CI or any related adverse events.
Measurements of pHe using colonic tonometry indicated malperfusion in all four patients who had developed clinically significant CI. A shorter duration of low pHe was well tolerated without any signs of CI. Measurement of pHe was safe and reliable for the surveillance of colonic perfusion after open aortic surgery, indicating a promising technique. However, larger studies are needed.
结肠缺血（CI）是主动脉手术后危及生命的并发症。可能需要对结肠灌注进行术后监测。本研究旨在评估经腹开放腹主动脉瘤（AAA）修复术后使用结肠测压法进行术后肠外 pH 值测量（pHe）的安全性和可行性。
在经腹开放 AAA 修复后关闭腹部之前，将测压导管经腹部放置在乙状结肠浆膜上，类似于引流导管。术后测量肠外二氧化碳分压，并结合动脉血气分析计算 pHe。每隔 4 小时测量一次，同时测量腹腔内压力。将结肠灌注不良的阈值设定为 pHe<7.2。
共监测 27 例患者，12 例患者因破裂性 AAA 接受手术，15 例患者因完整性 AAA 接受手术。27 例患者中，4 例发生需要手术治疗的临床显著 CI。所有 4 例均先出现持续时间较长（>5 小时）的 pHe<7.2 表明灌注不良。第五例患者在监测期间的 pHe 最低为 7.21，发生轻度 CI，在监测完成后开始，经保守治疗成功。7 例患者的 pHe<7.2 持续时间较短（<5 小时），未发生 CI 临床症状或任何相关不良事件。
使用结肠测压法测量 pHe 表明，所有 4 例发生临床显著 CI 的患者均存在灌注不良。较短时间的低 pHe 耐受良好，无 CI 迹象。pHe 测量对于开放主动脉手术后结肠灌注的监测是安全可靠的，表明这是一种有前途的技术。然而，还需要更大规模的研究。
