Comparison of unfractioned and low molecular weight heparin for prophylaxis of coagulopathies in 52 horses with colic: a randomised double-blind clinical trial.

REASONS FOR PERFORMING STUDY

Unfractioned heparin (UFH) is widely used for prophylaxis of coagulation disorders, especially in colic-affected horses. However, it is accompanied by certain side effects.

OBJECTIVES

To compare the efficacy and side effects of unfractioned and low molecular weight heparin (LMWH) in horses with colic.

METHODS

The study was carried out as a randomised, double-blind, controlled clinical trial. Fifty-two horses with colic were treated subcutaneously with either UFH (heparin calcium, 150 iu/kg bwt initially, followed by 125 iu/kg bwt q. 12 h for 3 days and then 100 iu/kg bwt q. 12 h) or LMWH (dalteparin, 50 iu/kg bwt q. 24 h). All horses underwent daily physical examination including assessment of jugular veins, local reaction to heparin injections, haematological evaluation and coagulation profiles over up to 9 days.

RESULTS

The type of heparin used did not affect the general behaviour and condition. There were significantly more jugular vein changes in horses treated with UFH. Packed cell volume decreased significantly within the first few days of UFH treatment, but did not change significantly in horses treated with LMWH. Activated partial thromboplastin time (aPTT) and thrombin time (TT) were prolonged in horses treated with UFH but not in those treated with LMWH.

CONCLUSIONS

It was concluded that, in comparison to UFH, LMWH has markedly fewer side effects in horses.

POTENTIAL RELEVANCE

Therefore, LMWH is recommended for prophylaxis of coagulation disorders in colic patients.