Abstract：
BACKGROUND: Intraoperative blood transfer between twins during laser surgery for twin-twin transfusion syndrome can vary by surgical technique and has been proposed to explain differences in donor twin survival.
OBJECTIVE: This trial compared donor twin survival with 2 laser techniques: the sequential technique, in which the arteriovenous communications from the volume-depleted donor to the volume-overloaded recipient are laser-occluded before those from recipient to donor, and the selective technique, in which the occlusion of the vascular communications is performed in no particular order.
METHODS: A single-center, open-label, randomized controlled trial was conducted in which twin-twin transfusion syndrome patients were randomized to sequential vs selective laser surgery. Nested within the trial, a second trial randomized patients with superficial anastomoses (arterioarterial and venovenous) to ablation of these connections first (before ablating the arteriovenous anastomoses) vs last. The primary outcome measure was donor twin survival at birth.
RESULTS: A total of 642 patients were randomized. Overall donor twin survival was similar between the 2 groups (274 of 320 [85.6%] vs 271 of 322 [84.2%]; odds ratio, 1.12 [95% confidence interval, 0.73-1.73]; P=.605). Superficial anastomoses occurred in 177 of 642 cases (27.6%). Donor survival was lower in the superficial anastomosis group vs those with only arteriovenous communications (125 of 177 [70.6%] vs 420 of 465 [90.3%]; adjusted odds ratio, 0.33 [95% confidence interval, 0.20-0.54]; P<.001). In cases with superficial anastomoses, donor survival was independent of the timing of ablation or surgical technique. The postoperative mean middle cerebral artery peak systolic velocity was lower in the sequential vs selective group (1.00±0.30 vs 1.06±0.30 multiples of the median; P=.003). Post hoc analyses showed 2 factors that were associated with poor overall donor twin survival: the presence or absence of donor twin preoperative critical abnormal Doppler parameters and the presence or absence of arterioarterial anastomoses. Depending on these factors, 4 categories of patients resulted: (1) Category 1 (347 of 642 [54%]), no donor twin critical abnormal Doppler + no arterioarterial anastomoses: donor twin survival was 91.2% in the sequential and 93.8% in the selective groups; (2) Category 2 (143 of 642 [22%]), critical abnormal Doppler present + no arterioarterial anastomoses: donor survival was 89.9% vs 75.7%; (3) Category 3 (73 of 642 [11%]), no critical abnormal Doppler + arterioarterial anastomoses present: donor survival was 94.7% vs 74.3%; and (4) Category 4 (79 of 642 [12%]), critical abnormal Doppler present + arterioarterial anastomoses present: donor survival was 47.6% vs 64.9%.
CONCLUSIONS: Donor twin survival did not differ between the sequential vs selective laser techniques and did not differ if superficial anastomoses were ablated first vs last. The donor twin\'s postoperative middle cerebral artery peak systolic velocity was improved with the sequential vs the selective approach. Post hoc analyses suggest that donor twin survival may be associated with the choice of laser technique according to high-risk factors. Further study is needed to determine whether using these categories to guide the choice of surgical technique will improve outcomes.
OBJECTIVE: This trial compared donor twin survival with 2 laser techniques: the sequential technique, in which the arteriovenous communications from the volume-depleted donor to the volume-overloaded recipient are laser-occluded before those from recipient to donor, and the selective technique, in which the occlusion of the vascular communications is performed in no particular order.
METHODS: A single-center, open-label, randomized controlled trial was conducted in which twin-twin transfusion syndrome patients were randomized to sequential vs selective laser surgery. Nested within the trial, a second trial randomized patients with superficial anastomoses (arterioarterial and venovenous) to ablation of these connections first (before ablating the arteriovenous anastomoses) vs last. The primary outcome measure was donor twin survival at birth.
RESULTS: A total of 642 patients were randomized. Overall donor twin survival was similar between the 2 groups (274 of 320 [85.6%] vs 271 of 322 [84.2%]; odds ratio, 1.12 [95% confidence interval, 0.73-1.73]; P=.605). Superficial anastomoses occurred in 177 of 642 cases (27.6%). Donor survival was lower in the superficial anastomosis group vs those with only arteriovenous communications (125 of 177 [70.6%] vs 420 of 465 [90.3%]; adjusted odds ratio, 0.33 [95% confidence interval, 0.20-0.54]; P<.001). In cases with superficial anastomoses, donor survival was independent of the timing of ablation or surgical technique. The postoperative mean middle cerebral artery peak systolic velocity was lower in the sequential vs selective group (1.00±0.30 vs 1.06±0.30 multiples of the median; P=.003). Post hoc analyses showed 2 factors that were associated with poor overall donor twin survival: the presence or absence of donor twin preoperative critical abnormal Doppler parameters and the presence or absence of arterioarterial anastomoses. Depending on these factors, 4 categories of patients resulted: (1) Category 1 (347 of 642 [54%]), no donor twin critical abnormal Doppler + no arterioarterial anastomoses: donor twin survival was 91.2% in the sequential and 93.8% in the selective groups; (2) Category 2 (143 of 642 [22%]), critical abnormal Doppler present + no arterioarterial anastomoses: donor survival was 89.9% vs 75.7%; (3) Category 3 (73 of 642 [11%]), no critical abnormal Doppler + arterioarterial anastomoses present: donor survival was 94.7% vs 74.3%; and (4) Category 4 (79 of 642 [12%]), critical abnormal Doppler present + arterioarterial anastomoses present: donor survival was 47.6% vs 64.9%.
CONCLUSIONS: Donor twin survival did not differ between the sequential vs selective laser techniques and did not differ if superficial anastomoses were ablated first vs last. The donor twin\'s postoperative middle cerebral artery peak systolic velocity was improved with the sequential vs the selective approach. Post hoc analyses suggest that donor twin survival may be associated with the choice of laser technique according to high-risk factors. Further study is needed to determine whether using these categories to guide the choice of surgical technique will improve outcomes.
摘要：
背景：双胎输血综合征（TTTS）激光手术期间双胎之间的术中输血可能因手术技术而异，并已被提议解释供体双胎存活率的差异。
目的：本试验比较了两种激光技术：序贯技术，其中从容量耗尽的供体到容量超负荷的受体的动静脉通信在从受体到供体之前被激光阻断；和选择性技术，其中血管通信的闭塞不按特定顺序进行。
方法：单中心，开放标签，我们进行了随机对照试验,其中TTTS患者被随机分为序贯和选择性激光手术.嵌套在审判中，第二项试验将浅表吻合(动脉和静脉)患者随机分为先消融这些连接(在消融动静脉吻合之前)和后消融.主要结果指标是出生时供体双胞胎的存活率。
结果：总共642例患者被随机分组。两组供体双胞胎的总体存活率相似（85.6％[274/320]对84.2％[271/322]，或1.12[0.73-1.73]，P=.605）。在27.6%(177/642)的病例中发生了浅吻合术。与仅有动静脉通信的患者相比，浅表吻合组的供体存活率较低（70.6%[125/177]对90.3%[420/465]，OR0.33[0.20-0.54],P<.001)。在浅层吻合的情况下，供者存活率与消融时机或手术技术无关.序贯组与选择性组术后平均大脑中动脉（MCA）收缩期峰值速度（PSV）较低（1.00±0.30对1.06±0.30MoM，P=.003）。事后分析显示，有2个因素与供体双胞胎总体生存率较差相关：供体双胞胎术前关键异常多普勒（CAD）参数的存在/不存在以及动脉动脉吻合（AA）的存在/不存在。根据这些因素,导致4类患者：（1）第1类（54%，347/642），无供体双胞胎CAD无AA：顺序组中供体双胞胎存活率为91.2％，选择性组中为93.8％；（2）类别2（22％，143/642），CAD存在+无AA：供体存活率为89.9%，而非75.7%；（3）类别3（11%，73/642），无CAD+AA存在：供体生存率为94.7%，而非74.3%；(4)第4类(12%，79/642），CAD存在+AA存在:供体存活率为47.6%对64.9%。
结论：序贯激光技术与选择性激光技术的供体双胞胎存活率没有差异，如果首先消融浅层吻合与最后消融，则没有差异。序贯方法与选择性方法相比，供体双胞胎的术后MCAPSV得到了改善。事后分析表明，根据高风险因素，供体双胞胎的存活可能与激光技术的选择有关。需要进一步的研究来了解使用这些类别来指导手术技术的选择是否会改善结果。
背景：没有外部资金的NCT02122328。
目的：本试验比较了两种激光技术：序贯技术，其中从容量耗尽的供体到容量超负荷的受体的动静脉通信在从受体到供体之前被激光阻断；和选择性技术，其中血管通信的闭塞不按特定顺序进行。
方法：单中心，开放标签，我们进行了随机对照试验,其中TTTS患者被随机分为序贯和选择性激光手术.嵌套在审判中，第二项试验将浅表吻合(动脉和静脉)患者随机分为先消融这些连接(在消融动静脉吻合之前)和后消融.主要结果指标是出生时供体双胞胎的存活率。
结果：总共642例患者被随机分组。两组供体双胞胎的总体存活率相似（85.6％[274/320]对84.2％[271/322]，或1.12[0.73-1.73]，P=.605）。在27.6%(177/642)的病例中发生了浅吻合术。与仅有动静脉通信的患者相比，浅表吻合组的供体存活率较低（70.6%[125/177]对90.3%[420/465]，OR0.33[0.20-0.54],P<.001)。在浅层吻合的情况下，供者存活率与消融时机或手术技术无关.序贯组与选择性组术后平均大脑中动脉（MCA）收缩期峰值速度（PSV）较低（1.00±0.30对1.06±0.30MoM，P=.003）。事后分析显示，有2个因素与供体双胞胎总体生存率较差相关：供体双胞胎术前关键异常多普勒（CAD）参数的存在/不存在以及动脉动脉吻合（AA）的存在/不存在。根据这些因素,导致4类患者：（1）第1类（54%，347/642），无供体双胞胎CAD无AA：顺序组中供体双胞胎存活率为91.2％，选择性组中为93.8％；（2）类别2（22％，143/642），CAD存在+无AA：供体存活率为89.9%，而非75.7%；（3）类别3（11%，73/642），无CAD+AA存在：供体生存率为94.7%，而非74.3%；(4)第4类(12%，79/642），CAD存在+AA存在:供体存活率为47.6%对64.9%。
结论：序贯激光技术与选择性激光技术的供体双胞胎存活率没有差异，如果首先消融浅层吻合与最后消融，则没有差异。序贯方法与选择性方法相比，供体双胞胎的术后MCAPSV得到了改善。事后分析表明，根据高风险因素，供体双胞胎的存活可能与激光技术的选择有关。需要进一步的研究来了解使用这些类别来指导手术技术的选择是否会改善结果。
背景：没有外部资金的NCT02122328。
