Humorally mediated thrombocytosis in major lower extremity trauma

Reoperation of Lower Extremity Microsurgical Reconstruction When Facing Postsplenectomy Thrombocytosis

Patients who sustain high-energy polytrauma are a unique population in that their mechanism of injury may induce multiorgan damage requiring immediate interventions such as splenectomy and bony fixation for mangled extremities. This results in the intersection of certain conditions, such as postsplenectomy thrombocytosis with the need for soft tissue reconstruction, often with free tissue transfer, for limb salvage after severe trauma to the lower extremity. However, there are no treatment guidelines in the management of postsplenectomy thrombocytosis in the setting of a lower extremity free flap reconstruction. We present a patient who had initial free tissue transfer to the lower extremity complicated by delayed microvascular thrombosis at postoperative day 4, during which time his platelet count exceeded more than 1,000,000/mm³. However, a successful second lower extremity free tissue transfer was achieved after platelet-reductive treatment with platelet apheresis during the perioperative period. Our patient went on to heal from his second free flap without further complications. Thus, thrombocytosis in the setting of free tissue transfer requires perioperative intervention to correct this hematologic condition. An innovative utilization of platelet apheresis may ensure the success of free tissue transfer by addressing the thrombocytosis in microsurgical patients after splenectomy.

Preoperative Platelet Count Predicts Lower Extremity Free Flap Thrombosis: A Multi-Institutional Experience

BACKGROUND

Thrombocytosis in patients undergoing lower extremity free tissue transfer may be associated with increased risk of microvascular complications. This study assessed whether preoperative platelet counts predict lower extremity free flap thrombosis.

METHODS

All patients undergoing lower extremity free tissue transfer at Duke University from 1997 to 2013 and at the University of Pennsylvania from 2002 to 2013 were retrospectively identified. Logistic regression was used to assess whether preoperative platelet counts independently predict flap thrombosis, controlling for baseline and operative factors.

RESULTS

A total of 565 patients underwent lower extremity free tissue transfer, with an overall flap thrombosis rate of 16 percent (n = 91). Elevated preoperative platelet counts were independently associated with both intraoperative thrombosis (500 ± 120 versus 316 ± 144 × 10/liter; p < 0.001) and postoperative thrombosis (410 ± 183 versus 320 ± 143 × 10/liter; p = 0.040) in 215 patients who sustained acute lower extremity trauma within 30 days before reconstruction. In acute trauma patients, preoperative platelet counts predicted a four-fold increased risk of intraoperative thrombosis (cutoff value, 403 × 10/liter; OR, 4.08; p < 0.001) and a two-fold increased risk of postoperative thrombosis (cutoff value, 361 × 10/liter; OR, 2.16; p = 0.005). In patients who did not sustain acute trauma, preoperative platelet counts predicted a four-fold increased risk of intraoperative thrombosis (cutoff value, 352 × 10/liter; OR, 3.82; p = 0.002).

CONCLUSIONS

Acute trauma patients with elevated preoperative platelet counts are at increased risk for lower extremity free flap complications. Prospective evaluation is warranted for guiding risk stratification and targeted treatment strategies.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Extreme Thrombocytosis after Penetrating Femoral Venous Injury

Lower extremity trauma is an uncommon cause of reactive thrombocytosis. A 17-year-old male patient with an extreme increase in platelet count caused by penetrating femoral venous injury is presented. During his stay in hospital, two thrombotic attacks were observed. Such events should be considered as high risk for thrombosis and anticoagulant therapy administered.