Abstract 238: A Pilot Observational Study of Coagulation Function Following Resuscitation From Cardiac Arrest With Rapid Induction of Therapeutic Hypothermia
Introduction: The acute coagulation response to resuscitation from cardiac arrest and how it may be modulated by therapeutic hypothermia (TH) has been identified by the International Liaison Committee on Resuscitation as an important topic for study. We use a prospective pilot study to examine the coagulation response of resuscitated cardiac arrest patients undergoing rapid TH.
Methods: TH was initiated prehospital in cardiac arrest victims by iced saline infusion during CPR and then maintained at 33 deg C for up to 48 hours using a cooling catheter. Coagulation was measured during TH (0, 12 and 36 hours after arrival) and daily during the latter period of normothermia (NT) (Hospital days 3–7). Plasma coagulation tests were performed at 37 deg C and Thrombelastography (TEG) was performed at both hypothermic body temperature and at 37 deg C in order to elicit TH-dependent effects on clot formation. Coagulation parameters were compared between TH and NT periods using paired t-tests and associations were made by correlation analysis.
Results: N=3 patients were analyzed after exclusion of those receiving anticoagulation. Core body temperature was significantly lower during TH (mean body temp= 34.1(TH) vs. 37.6(NT) deg C, p=0.012). Platelet count was not different (p=0.99) and prothrombin /activated partial thromboplastin times were prolonged during TH but not significantly so when compared to the period of NT (p>0.18). Fibrinogen was elevated during TH and tended to increase further during NT (mean fibrinogen= 396.9 mg/dl (TH) vs. 768.9 mg/dl (NT), p=0.06). TEG clot onset times were not prolonged and clot strength (MA) indicated a hypercoagulable state during TH that increased further during NT (mean MA=69.6 mm (TH) vs. 76.2 mm (NT), p=0.04). Increasing TEG assay temperature to 37 deg C in blood sampled during TH had no effect on clot strength (mean MA=69.4 mm (Body Temp) vs. 69.5 mm (37 deg C), p=0.97). Fibrinogen was strongly and positively correlated with MA regardless of TH (TH:R=0.81, p<0.0001, NT: R=0.62, p=0.03).
Conclusions: In this pilot study, post-resuscitation TH had little influence on whole-blood clotting parameters that tended to demonstrate enhanced clot strength associated with rapidly rising plasma fibrinogen.
- © 2010 by American Heart Association, Inc.