Aterial thromboses after platelet transfusion in context of emergency AAA

Background

  • Recent patient, underwent emergency open AAA for rupture.
  • 3 x MTPs used, with platelets as part of the 2nd MTP, as per local guideline.
  • Survived initial surgery, went to ICU.
  • Returned to OT later that day for bilateral lower limb arterial thrombectomies.
  • Surgeon suggested that the use of platelets as part of the MTP in this setting may have contributed to the thromboses.

Discussion

  • Should we be using different MTPs for major emergency vascular surgery?
    • A small prospective single-blinded randomised study published in Transfusion Medicine found no increase in adverse events or survival impact from platelet transfusion in ruptured AAA patients before transfer to a tertiary centre for surgery. DOI: 10.1111/tme.12540
    • In elective AAA surgery, heparin is used prior to aortic cross-clamp to minimise the risk of arterial thrombosis. While seemingly counter-intuitive in the bleeding patient, should this be considered in emergency surgery also?
    • Blood transfusion is rapid and voluminous in emergency AAA surgery. Formal bloods results will be outdated by the time they are available and using TEG unless extremely familiar with it +/- with a dedicated technician can be distracting and time consuming.
    • Once the initial urgency has passed, restrictive transfusion strategies guided by results becomes more appropriate.

Overall it was felt that at this stage, sticking to current locally endorsed MTP guidelines is appropriate, however communication with the surgeon around appropriate blood product use is recommended.