E. McCarthy Deering, S. Y. Hu, Royal College of Surgeons, Dublin, Ireland A. Abdulkarim, Department of Trauma & Orthopaedic Surgery, Cambridge University Hospital, Addenbrooke's Hospital, Cambridge, UK, email:
Clin Orthop Relat Res. 2019 Mar;477(3):547-558. doi: 10.1097/CORR.0000000000000572.
Although tourniquets are commonly used during TKA, that practice has long been surrounded by controversy. Quantifying the case for or against tourniquet use in TKA, in terms of patient-reported outcomes such as postoperative pain, is a priority.
QUESTIONS/PURPOSES: The purpose of this study was to meta-analyze the available randomized trials on tourniquet use during TKA to determine whether use of a tourniquet during TKA (either for the entire procedure or some portion of it) is associated with (1) increased postoperative pain; (2) decreased ROM; and (3) longer lengths of hospital stay (LOS) compared with TKAs performed without a tourniquet.
We completed a systematic review and meta-analysis using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines to assess the impact of tourniquet use on patients after TKA. We searched the following databases from inception to February 1, 2015, for randomized controlled trials meeting prespecified inclusion criteria: PubMed, Embase, and Cochrane Central Register of Controlled Trials. Postoperative pain was the primary outcome. Secondary outcomes were postoperative ROM and LOS. The initial search yielded 218 studies, of which 14 met the inclusion criteria. For our primary analysis on pain and ROM, a total of eight studies (221 patients in the tourniquet group, 219 patients in the no-tourniquet group) were meta-analyzed. We also performed a subgroup meta-analysis on two studies that used the tourniquet only for a portion of the procedure (from osteotomy until the leg was wrapped with bandages) and defined this as half-course tourniquet use (n = 62 in this analysis). The Jadad scale was used to ascertain methodological quality, which ranged from 3 to 5 with a maximum possible score of 5. Statistical heterogeneity was tested with I and chi-square tests. A fixed-effects (inverse variance) model was used when the effects were homogenous, which was only the case for postoperative pain; the other endpoints had moderate or high levels of heterogeneity. Publication bias was assessed using a funnel plot, and postoperative pain showed no evidence of publication bias, but the endpoint of LOS may have suffered from publication bias or poor methodological quality. We defined the minimum clinically important difference (MCID) in pain as 20 mm on the 100-mm visual analog scale (VAS).
We found no clinically important difference in mean pain scores between patients treated with a tourniquet and those treated without one (5.23 ± 1.94 cm versus 3.78 ± 1.61 cm; standardized [STD] mean difference 0.88 cm; 95% confidence interval [CI], 0.54-1.23; p < 0.001). None of the studies met the MCID of 20 mm in VAS pain scores. There was also no clinically important difference in ROM based on degrees of flexion between the two groups (49 ± 21 versus 56 ± 22; STD mean difference 0.8; 95% CI, 0.4-1.1; p < 0.001). Similarly, we found no difference in mean LOS between groups (5.8 ± 4.4 versus 5.9 ± 4.6; STD mean difference -0.2; 95% CI, -0.4 to 0.1; p = 0.25). A subgroup meta-analysis also showed no clinically important difference in pain between the full-course and half-course tourniquet groups (5.17 ± 0.98 cm versus 4.09 ± 1.08 cm; STD mean difference 1.31 cm; 95% CI, -0.16 to 2.78; p = 0.08).
We found no clinically important differences in pain or ROM between patients treated with and without tourniquets during TKA and no differences between the groups in terms of LOS. In the absence of short-term benefits of avoiding tourniquets, long-term harms must be considered; it is possible that use of a tourniquet improves a surgeon's visualization of the operative field and the quality of the cement technique, either of which may improve the long-term survivorship or patient function, but those endpoints could not be assessed here. We recommend that the randomized trials discussed in this meta-analysis follow patients from the original series to determine if there might be any long-term differences in pain or ROM after tourniquet use.
Level I, therapeutic study.
在 TKA 中，止血带通常被广泛应用，但长期以来，其使用一直存在争议。量化止血带在 TKA 中的应用对患者报告的结果（如术后疼痛）的影响是当务之急。
本研究通过对 TKA 中使用止血带的随机试验进行荟萃分析，来确定 TKA 过程中使用止血带（无论是整个过程还是部分过程）是否与（1）术后疼痛增加；（2）ROM 减少；（3）住院时间（LOS）延长有关，与不使用止血带的 TKA 相比。
我们按照 PRISMA 报告指南进行了系统评价和荟萃分析，以评估 TKA 后使用止血带对患者的影响。我们从创建到 2015 年 2 月 1 日，在以下数据库中搜索符合预定义纳入标准的随机对照试验：PubMed、Embase 和 Cochrane 中央对照试验注册库。术后疼痛是主要结局。次要结局是术后 ROM 和 LOS。初始搜索产生了 218 项研究，其中 14 项符合纳入标准。对于我们关于疼痛和 ROM 的主要分析，共对 8 项研究（止血带组 221 例患者，无止血带组 219 例患者）进行了荟萃分析。我们还对仅在部分手术过程中使用止血带（从截骨到腿部用绷带包扎）的两项研究进行了亚组荟萃分析，并将此定义为半程止血带使用（本分析中 n = 62）。使用 Jadad 量表评估方法学质量，得分范围为 3 至 5 分，最高可能得分为 5 分。使用 I 平方和卡方检验测试效应的异质性。当效应同质时，使用固定效应（逆方差）模型，仅在术后疼痛的情况下如此；其他终点存在中度或高度异质性。使用漏斗图评估发表偏倚，术后疼痛未显示发表偏倚的证据，但 LOS 终点可能存在发表偏倚或方法学质量差的问题。我们将疼痛的最小临床重要差异（MCID）定义为视觉模拟量表（VAS）上的 20mm。
我们发现使用止血带和不使用止血带的患者之间的平均疼痛评分没有临床重要差异（5.23 ± 1.94cm 与 3.78 ± 1.61cm；标准化均数差 0.88cm；95%置信区间[CI]，0.54-1.23；p < 0.001）。没有一项研究在 VAS 疼痛评分上达到 20mm 的 MCID。两组之间的屈伸 ROM 也没有临床重要差异（49 ± 21°与 56 ± 22°；标准化均数差 0.8°；95% CI，0.4-1.1°；p < 0.001）。同样，我们发现两组之间的平均 LOS 没有差异（5.8 ± 4.4 与 5.9 ± 4.6；标准化均数差 -0.2；95% CI，-0.4 至 0.1；p = 0.25）。亚组荟萃分析也显示，全程和半程止血带组之间的疼痛没有临床重要差异（5.17 ± 0.98cm 与 4.09 ± 1.08cm；标准化均数差 1.31cm；95% CI，-0.16 至 2.78；p = 0.08）。
我们发现，在 TKA 中使用和不使用止血带的患者在疼痛或 ROM 方面没有临床重要差异，在 LOS 方面也没有差异。在没有避免使用止血带的短期益处的情况下，必须考虑长期危害；使用止血带可能会改善外科医生对手术视野的可视化和骨水泥技术的质量，这两者都可能改善长期生存率或患者功能，但这些终点在这里无法评估。我们建议，本荟萃分析中讨论的随机试验应随访原始系列患者，以确定使用止血带后是否存在疼痛或 ROM 的任何长期差异。
I 级，治疗性研究。
