Drs. Slater and Lerner have reemphasized a critical point in our published case scenario1 : Standard coagulation tests are inadequate in assessing adequacy of platelet function for epidural catheterization. Therefore, we recommended in our algorithm presented in figure 4 of our original report1 to use whole blood multiple electrode impedance aggregometry (Multiplate®; Roche Diagnostics, Mannheim, Germany) or whole blood turbidimetric aggregometry (VerifyNow®; Accumetrics, San Diego, CA) to support decision making in patients with antiplatelet therapy.1 Multiple electrode impedance aggregometry and VerifyNow® have been used to assess the efficacy of antiplatelet drugs and the dynamics of platelet function recovery after clopidogrel treatment—also under the scenario “risk–benefit analysis of neuraxial blockade.”2–7 Multiple electrode impedance aggregometry is as sensitive as light transmission aggregometry (Born aggregometry—the definitive standard of platelet function analysis) to detect platelet dysfunction,8,9 predict stent thrombosis and bleeding rates after coronary interventions,2,10 and can be used as a guide to support treatment of hemorrhagic patients undergoing cardiac surgery.11,12
Please note that the value of thromboelastography or thromboelastometry in our case scenario relates to detection of trauma-induced coagulopathy with reduced clot firmness13 and hypercoagulability due to an acute phase reaction with high plasma fibrinogen concentrations, which we know occurs frequently after the acute phase of trauma-induced coagulopathy.14,15
Dr. Flores suggests the use of multilevel continuous intercostal nerve block catheter in a patient with flail chest. Although the risk of epidural hematoma may be lower with intercostal nerve blocks compared with epidural analgesia, other risks such as pneumothorax/hematothorax and inadequate efficacy may limit its use under the condition described in our case scenario.
We need to develop specific outcome-oriented clinical pathways in critical care medicine that do not exclusively take into account the data taken from elective surgical procedures in the operating room. In patients with flail chest presenting with traditional contraindications for neuraxial analgesia, careful risk–benefit analysis may indicate that epidural analgesia improves important outcome measures. We believe that thromboelastography or thromboelastometry and aggregometry (if available) are helpful instruments for decision support in such a case scenario.