Correspondence  |   October 2013
In Reply
Author Affiliations & Notes
  • (Accepted for publication July 1, 2013.)
    (Accepted for publication July 1, 2013.)×
Article Information
Correspondence   |   October 2013
In Reply
Anesthesiology 10 2013, Vol.119, 994-995. doi:10.1097/ALN.0b013e3182a462b1
Anesthesiology 10 2013, Vol.119, 994-995. doi:10.1097/ALN.0b013e3182a462b1
In Reply:
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.
Young Ahn, M.D., Klaus Görlinger, M.D., Matthias Eikermann, M.D., Ph.D.* *Massachusetts General Hospital, Boston, Massachusetts.
Ahn, Y, Görlinger, K, Alam, HB, Eikermann, M Pain-associated respiratory failure in chest trauma.. Anesthesiology. (2013). 118 701–8 [Article] [PubMed]
Sibbing, D, Braun, S, Morath, T, Mehilli, J, Vogt, W, Schömig, A, Kastrati, A, von Beckerath, N Platelet reactivity after clopidogrel treatment assessed with point-of-care analysis and early drug-eluting stent thrombosis.. J Am Coll Cardiol. (2009). 53 849–56 [Article] [PubMed]
Price, MJ, Teirstein, PS Dynamics of platelet functional recovery following a clopidogrel loading dose in healthy volunteers.. Am J Cardiol. (2008). 102 790–5 [Article] [PubMed]
Perakis, PG, Yunus, T, Long, G, Cheema, ZF, Hammond, R, Shanley, CJ Platelet function after cessation of chronic clopidogrel therapy.. Am Surg. (2012). 78 51–6 [PubMed]
Bergmann, L, Kienbaum, P, Görlinger, K, Peters, J Uneventful removal of an epidural catheter guided by impedance aggregometry in a patient with recent coronary stenting and treated with clopidogrel and acetylsalicylic acid.. Reg Anesth Pain Med. (2007). 32 354–7 [Article] [PubMed]
Benzon, HT, McCarthy, RJ, Benzon, HA, Kendall, MC, Robak, S, Lindholm, PF, Kallas, PG, Katz, JA Determination of residual antiplatelet activity of clopidogrel before neuraxial injections.. Br J Anaesth. (2011). 107 966–71 [Article] [PubMed]
Limper, U, Lynch, J [Removal of epidural catheter under dual antiplatelet therapy following acute coronary syndrome: Scenario without special consideration to the current guidelines on epidural regional anesthesia].. Anaesthesist. (2012). 61 686–90 [Article] [PubMed]
Velik-Salchner, C, Maier, S, Innerhofer, P, Streif, W, Klingler, A, Kolbitsch, C, Fries, D Point-of-care whole blood impedance aggregometry versus classical light transmission aggregometry for detecting aspirin and clopidogrel: The results of a pilot study.. Anesth Analg. (2008). 107 1798–806 [Article] [PubMed]
Sibbing, D, Braun, S, Jawansky, S, Vogt, W, Mehilli, J, Schömig, A, Kastrati, A, von Beckerath, N Assessment of ADP-induced platelet aggregation with light transmission aggregometry and multiple electrode platelet aggregometry before and after clopidogrel treatment.. Thromb Haemost. (2008). 99 121–6 [PubMed]
Sibbing, D, Schulz, S, Braun, S, Morath, T, Stegherr, J, Mehilli, J, Schömig, A, von Beckerath, N, Kastrati, A Antiplatelet effects of clopidogrel and bleeding in patients undergoing coronary stent placement.. J Thromb Haemost. (2010). 8 250–6 [Article] [PubMed]
Görlinger, K, Dirkmann, D, Hanke, AA, Kamler, M, Kottenberg, E, Thielmann, M, Jakob, H, Peters, J First-line therapy with coagulation factor concentrates combined with point-of-care coagulation testing is associated with decreased allogeneic blood transfusion in cardiovascular surgery: A retrospective, single-center cohort study.. Anesthesiology. (2011). 115 1179–91 [PubMed]
Weber, CF, Görlinger, K, Meininger, D, Herrmann, E, Bingold, T, Moritz, A, Cohn, LH, Zacharowski, K Point-of-care testing: A prospective, randomized clinical trial of efficacy in coagulopathic cardiac surgery patients.. Anesthesiology. (2012). 117 531–47 [Article] [PubMed]
Davenport, R, Manson, J, De’Ath, H, Platton, S, Coates, A, Allard, S, Hart, D, Pearse, R, Pasi, KJ, MacCallum, P, Stanworth, S, Brohi, K Functional definition and characterization of acute traumatic coagulopathy.. Crit Care Med. (2011). 39 2652–8 [PubMed]
Ang, L, Palakodeti, V, Khalid, A, Tsimikas, S, Idrees, Z, Tran, P, Clopton, P, Zafar, N, Bromberg-Marin, G, Keramati, S, Mahmud, E Elevated plasma fibrinogen and diabetes mellitus are associated with lower inhibition of platelet reactivity with clopidogrel.. J Am Coll Cardiol. (2008). 52 1052–9 [Article] [PubMed]
Mahmud, E, Cavendish, JJ, Tsimikas, S, Ang, L, Nguyen, C, Bromberg-Marin, G, Schnyder, G, Keramati, S, Palakodeti, V, Penny, WF, DeMaria, AN Elevated plasma fibrinogen level predicts suboptimal response to therapy with both single- and double-bolus eptifibatide during percutaneous coronary intervention.. J Am Coll Cardiol. (2007). 49 2163–71 [Article] [PubMed]