Extracorporeal membrane oxygenation (ECMO) has been widely used in the treatment of various acute and critical heart and respiratory failure diseases. However, platelet (PLT) counts decrease significantly during the treatment, which increases the risk of bleeding and thus affecting the prognosis of patients. Therefore, the explore of changes in PLT counts during ECMO support can help prevent bleeding related risks caused by thrombocytopenia, thus improving the prognosis of patients.

To retrospectively analyse the changes of PLT counts during ECMO support under different support modes.

40 adult patients received veno-venous ECMO (V-V ECMO) or veno-arterial ECMO (V-A ECMO) support from January 2019 to October 2021 at the heart center of the People's Hospital of Gaozhou were included as study subjects and divided into the death group (n=22) and survival group (n=18) according to the occurrence of death after ECMO. PLT and platelet infusion were collected at baseline, before ECMO, and during the intervention.

The average age of patients was (49.0±17.8) years, and the average duration of ECMO support was (6.0±3.2) days. There was statistically significant difference in the proportion of ECMO intervention reasons between the operation group and the non-operation group (P<0.05). The incidence of thrombocytopenia before ECMO support was 18% (7/40), among which three patients were treated with V-V ECMO, all of whom suffering from severe pneumonia, and four patients were treated with V-A ECMO. After 1 day of ECMO support, the incidence of thrombocytopenia was 56.0% (18/32), among which four patients were treated with V-V ECMO, fourteen patients were treated with V-A ECMO. Nine patients in the non-operation group and 13 patients in the operation group received platelet transfusion. The effective rate of initial platelet transfusion was 59.1% (13/22). The proportion of thrombocytopenia before ECMO support in the operation group was higher than that in the non-operation group, with statistically significant difference (P<0.05). The lowest PLT count was observed on day 4 of ECMO in the non-operation group and day 5 of ECMO support in the operation group. The age of patients in the death group was higher than that in the non-death group, and the ECMO support time, weaning rate and PLT count on the day 7 of ECMO support were lower than those in the non-death group, with statistically significant difference (P<0.05) .

PLT count reached the lowest value on the day 3-4 of ECMO support and correlated with the prognosis of patients. The initial infusion of allogeneic platelets can increase PLT count in patients, suggesting that the corresponding intervention preparations should be made according to the changes of PLT in clinical practice, so as to reduce bleeding and other complications caused by thrombocytopenia and improve the prognosis of patients receiving ECMO support.

体外膜肺氧合（ECMO）已被广泛应用于治疗各类急危重症的心脏及呼吸功能衰竭疾病，但治疗过程中血小板计数（PLT）会显著下降，导致患者出血风险增加，从而影响患者预后。因此，研究ECMO治疗期间PLT的变化规律，有助于预防血小板下降所导致的出血相关风险，从而改善患者预后。

回顾性分析不同支持模式下成人ECMO支持期间PLT的变化规律。

纳入高州市人民医院心脏中心2019年1月—2021年10月进行静脉-静脉ECMO（V-V ECMO）或静脉-动脉ECMO（V-A ECMO）支持治疗的40例成年患者为研究对象。根据患者是否行心脏手术分为手术组（n=23）与非手术组（n=17），根据患者ECMO干预后是否死亡分为死亡组（n=22）和存活组（n=18）。收集患者基线资料，同时收集患者基线、ECMO前、干预期间PLT及血小板输注情况。

患者平均年龄（49.0±17.8）岁，平均ECMO支持时间（6.0±3.2）d。手术组与非手术组患者ECMO干预原因比例比较，差异有统计学意义（P<0.05）。ECMO干预前患者血小板减少发生率为18%（7/40），其中3例采用V-V ECMO，均患有重症肺炎，4例采用V-A ECMO；ECMO支持1 d后血小板减少发生率为56.0%（18/32），其中4例采用V-V ECMO，14例采用V-A ECMO；非手术组有9例患者输注血小板治疗，手术组患者有13例输注血小板治疗，患者首次血小板输注有效率为59.1%（13/22）。手术组ECMO前血小板减少比例高于非手术组（P<0.05）。非手术组ECMO支持第4天PLT最低，手术组ECMO支持第5天PLT最低。死亡组患者年龄高于存活组，ECMO支持时间、脱机率、ECMO支持第7天PLT低于存活组（P<0.05）。

ECMO支持下的PLT于第3~4天达到最低值，患者预后与PLT存在相关性。患者首次输注异体血小板可以提升PLT，提示临床上可以根据PLT变化规律做好相应的干预准备，减少PLT过低引发出血等并发症，改善接受ECMO患者的预后。