From R Adams Cowley Shock Trauma Center (A.W., R.V.O., E.H., M.F.S., A.N.P., T.T.M., W.A.E., R.C.A., C.L., J.W.N.), Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland; and Department of Orthopaedics (C.D.), University of Wisconsin School of Medicine, Madison, Wiconsin.
J Trauma Acute Care Surg. 2014 Feb;76(2):479-83. doi: 10.1097/TA.0b013e3182aaa63e.
Intracompartmental pressure measurements are frequently used in the diagnosis of compartment syndrome, particularly in patients with equivocal or limited physical examination findings. Little clinical work has been done to validate the clinical use of intracompartmental pressures or identify associated false-positive rates. We hypothesized that diagnosis of compartment syndrome based on one-time pressure measurements alone is associated with a high false-positive rate.
Forty-eight consecutive patients with tibial shaft fractures who were not suspected of having compartment syndrome based on physical examinations were prospectively enrolled. Pressure measurements were obtained in all four compartments at a single point in time immediately after induction of anesthesia using a pressure-monitoring device. Preoperative and intraoperative blood pressure measurements were recorded. The same standardized examination was performed by the attending surgeon preoperatively, postoperatively, and during clinical follow-up for 6 months to assess clinical evidence of acute or late compartment syndrome.
No clinical evidence of compartment syndrome was observed postoperatively or during follow-up until 6 months after injury. Using the accepted criteria of delta P of 30 mm Hg from preoperative diastolic blood pressure, 35% of cases (n = 16; 95% confidence interval, 21.5-48.5%) met criteria for compartment syndrome. Raising the threshold to delta P of 20 mm Hg reduced the false-positive rate to 24% (n = 11; 95% confidence interval, 11.1-34.9%). Twenty-two percent (n = 10; 95% confidence interval, 9.5-32.5%) exceeded absolute pressure of 45 mm Hg.
A 35% false-positive rate was found for the diagnosis of compartment syndrome in patients with tibial shaft fractures who were not thought to have compartment syndrome by using currently accepted criteria for diagnosis based solely on one-time compartment pressure measurements. Our data suggest that reliance on one-time intracompartmental pressure measurements can overestimate the rate of compartment syndrome and raise concern regarding unnecessary fasciotomies.
Diagnostic study, level II.
在诊断筋膜室综合征时，常进行筋膜室内压力测量，尤其是在体格检查结果不确定或有限的患者中。目前很少有临床工作来验证筋膜室内压力的临床应用或确定相关的假阳性率。我们假设，仅根据单次压力测量来诊断筋膜室综合征，其假阳性率较高。
连续纳入 48 例胫骨骨干骨折且根据体格检查不怀疑患有筋膜室综合征的患者。在麻醉诱导后，使用压力监测设备立即在一个时间点对所有 4 个筋膜室进行压力测量。记录术前和术中的血压测量值。由主治医生在术前、术后和临床随访 6 个月时进行相同的标准化检查，以评估急性或迟发性筋膜室综合征的临床证据。
术后或随访至受伤后 6 个月均未观察到筋膜室综合征的临床证据。使用术前舒张压 30mmHg 的 ΔP 作为公认的标准，35%的病例（n=16；95%置信区间，21.5%-48.5%）符合筋膜室综合征的标准。将阈值提高到 20mmHg 的 ΔP 可将假阳性率降低至 24%（n=11；95%置信区间，11.1%-34.9%）。22%（n=10；95%置信区间，9.5%-32.5%）的病例绝对压力超过 45mmHg。
在不考虑目前基于单次筋膜室压力测量的诊断标准的情况下，我们认为胫骨骨干骨折患者的筋膜室综合征诊断存在 35%的假阳性率。我们的数据表明，单次筋膜室内压力测量的依赖可能高估筋膜室综合征的发生率，并引起对不必要的筋膜切开术的担忧。
诊断研究，Ⅱ级。
