Surgical bleeding after pre-operative unfractionated heparin and low molecular weight heparin for coronary bypass surgery

Abstract

Background and ObjectivesSince the impairment of platelet function may cause excess peri-operative bleeding, pre-operative discontinuation of aspirin and heparin bridging are common for cardiac surgery. We evaluated the impact of pre-operative administration of enoxaparin and unfractionated heparin (UFH) on coagulation parameters and peri-operative bleeding in patients undergoing elective coronary artery bypass grafting (CABG) surgery after discontinuation of aspirin. Design and MethodsForty-three patients with three-vessel coronary artery disease undergoing elective CABG surgery discontinued aspirin and were randomized to receive either UFH 180 UI/Kg × 2/day s.c. or enoxaparin 100 UI/Kg × 2/day s.c. until 12 h before surgery (median pre-operative treatment 8 days, range 6-12 days). Surgery was performed as usual with UFH. Neither UFH nor any low molecular weight heparin was given in the immediate post-operative period. The effects of UFH and enoxaparin were monitored by the activated partial thromboplastin time (aPTT) and the Enox-test (sensitive to factor Xa inhibition) using a Rapidpoint®Coagulation Analyzer. aPTT and factor Xa activity were also measured by standard methods. Peri-operative bleeding and the nadirs of hemoglobin concentration, hematocrit and platelet count were monitored post-operatively. ResultsPatients in the two groups were similar for number of bypasses, on-pump time, total surgery time, and time from the last heparin administration. Coagulation parameters increased significantly and similarly at 30 min and 6 h with both treatments, but returned within the normal range at 12 h. Hemoglobin, hematocrit and platelet counts significantly decreased to the same extent after CABG and re-normalized at the same time. Transfusional requirements of blood and plasma units were similar in the two groups. Interpretation and ConclusionsFrom the kinetics of coagulation parameters and the evaluation of bleeding, enoxaparin is a safe alternative to UFH as a bridging therapy to CABG after discontinuation of aspirin.

Effects of Preoperative Enoxaparin on Bleeding after Coronary Artery Bypass Surgery

“…Some of these studies showed no significant risk of bleeding in those patients compared to subjects receiving UFH [9][10]. In fact, Renda et al found that transfusional requirements of blood and plasma was similar in patients receiving either UFH or LMWH (stopped 12 hours prior to surgery) but their study had sample size limitation [9]. Medalion et al found also that administration of enoxaparin more than 8 hours before surgery did not increase bleeding or products' transfusion rate [10].…”

Unterbrechung antithrombotischer Behandlung (Bridging) bei kardialen Erkrankungen

“…B. Enoxaparin 1 mg/ kg 2-mal täglich, Dalteparin 100 IE/kg 2-mal täglich u. a. [1] Über den für eine Gerinnungsnormalisierung notwendigen zeitlichen Abstand zwischen der letzten Gabe niedermolekularen Heparins und dem Eingriff liegen unterschiedliche Daten vor [18,20,21]: 24 h Abstand mit Reduktion der letzten Dosis auf die Hälfte sind zu bevorzugen [1].…”

“…Sie hat sich aufgrund der kalkulierbaren Antikoagulation bereits zu Therapiebeginn wie auch wegen der größeren Mobilität der Patienten bei s.c.-Gabe als zu bevorzugende Alternative zu unfraktioniertem Heparin erwiesen [1,8,20,22,23,27]. Dieses Vorgehen ist nach der aktuellen US-amerikanischen Leitlinie [1] inzwischen auch für das Bridging bei Patienten mit mechanischem Herzklappenersatz anwendbar, allerdings favorisierte die letzte europäische Leitlinie noch unfraktioniertes Heparin [15].…”

Risk of bleeding in surgical patients treated with topical bovine thrombin sealants: a review of the literature

“…We identified 16 studies that met our inclusion criteria, which are presented in Additional file 1 , Table 1 [ 21 - 36 ]. Seven of these studies were cardiovascular surgery studies [ 25 , 27 , 28 , 31 , 32 , 35 , 36 ], three were pancreatic surgery [ 21 , 24 , 29 ], and the others included major abdominal surgery [ 23 ], major orthopedic surgery [ 33 ], non-cardiac general surgery [ 34 ], laparoscopic cholecystectomy [ 26 ], prostatic resection [ 22 ], and laparoscopic and thoracoscopic surgery [ 30 ]. Seven of the studies included more than 1,000 patients[ 23 , 24 , 26 , 28 , 30 , 31 , 33 ].…”