1. High-dose tinzaparin in pregnancy and the need for urgent delivery
S.K. Backe, G.R. Lyons 
British Journal of Anaesthesia 
Volume 89, Issue 2, Pages (August 2002)
DOI: /bja/aef189
Copyright © 2002 British Journal of Anaesthesia Terms and Conditions

2. Fig 1
A TEG® trace represents the formation of a blood clot over time with the start of clot initiation shown by the division of the trace from a straight line. The amplitude of the split is proportional to the clot strength. The TEG® trace of patient in case report 1 at 8 h post-tinzaparin administration is a straight line (in bold) which indicates a failure of clot initiation.
British Journal of Anaesthesia  , DOI: ( /bja/aef189)
Copyright © 2002 British Journal of Anaesthesia Terms and Conditions

3. Fig 2
The TEG® trace seen in bold is the trace of patient in case report 1 at 22 h post-tinzaparin of dose 175 IU kg−1 given subcutaneously. The division of the straight line shows the initiation of clot and the final clot strength is shown by the amplitude of the split. The effect of LMWH is shown on the TEG® trace in bold as a delay in clot initiation. The corresponding anti-Xa concetration is in the range our laboratory considers adequate for thromboprophylaxis. Both TEG® trace and anti-Xa concentration demonstrate the prolonged effect of a therapeutic dose of tinzaparin.
British Journal of Anaesthesia  , DOI: ( /bja/aef189)
Copyright © 2002 British Journal of Anaesthesia Terms and Conditions

4. Fig 3
(a) The TEG trace of patient in case report 2 shows a late split and a poor amplitude when compared with the curve normally seen in pregnancy demonstrating hypocoagulability at 4 h after a therapeutic dose of tinzaparin. When protamine sulphate was added to the same sample in vitro (b) clot formation was quicker and stronger.
British Journal of Anaesthesia  , DOI: ( /bja/aef189)
Copyright © 2002 British Journal of Anaesthesia Terms and Conditions

5. Fig 4
The TEG® trace normally seen in pregnancy. The variables measured are: (1) r time (reaction time) which is the time of initial fibrin formation (measured as the time from start to a 1 mm deflection in the TEG® trace); (2) k time which reflects the period of rapid fibrin build-up and crosslinking (measured from the end of the r time to a 20 mm width deflection in the trace); (3) alpha angle which represents the speed of clot formation, fibrin crosslinking, and platelet-fibrin interaction and MA, which reflects a measure of the final clot strength and depends on fibrinogen concentration, platelet numbers and function.
British Journal of Anaesthesia  , DOI: ( /bja/aef189)
Copyright © 2002 British Journal of Anaesthesia Terms and Conditions