A case report of detecting subclinical coagulopathy in a patient with boomslang (Dipholidus typus) bite

Abstract

The boomslang (Dipholidus typus) has a predominantly haemotoxic venom. Because of the consumptive nature of the coagulopathy, signs and symptoms are usually delayed by up to 72 h after the bite. Traditional laboratory coagulation assays have a long turnaround time, by which time the patient’s bleeding and clotting profile has changed. A 25-year-old male patient was bitten by a boomslang. Despite two normal laboratory coagulation assay results, a point-of-care rotational thromboelastometry showed low fibrinogen levels, leading to the administration of monovalent antivenom. This report highlights the value of point-of-care thromboelastometry in the care of patients with subclinical boomslang envenomation.

Ruthenium Antivenom Inhibits the Defibrinogenating Activity of Crotalus adamanteus Venom in Rabbits

“…While the utility of thrombelastographic methods in assessing the effects of hemotoxic venom was presented in the Introduction [ 5 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ], the present study serves as an example wherein thrombelastography provides a depth of information not afforded by standard hematological methods. Rather than just documented decreases in fibrinogen concentration with either clotting-based or antigen-based methods following envenomation, the use of thrombelastography without and with platelet inhibition allowed the quantification of the impact of the loss of fibrinogen on all aspects of coagulation ( Figure 3 , Figure 4 , Figure 5 and Figure 6 ).…”

“…A methodology capable of documenting the effects of loss of fibrinogen in whole blood or plasma is thrombelastography, which has been utilized in clinical [ 5 ] and laboratory investigations [ 13 ] involving C. adamanteus venom. While one of the first utilizations of thrombelastography/thromboelastometry to assess coagulopathy after envenomation was reported thirty-four years ago [ 14 ], the vast majority of clinical and laboratory reports in human and veterinary settings have been published in the last decade, with a few examples cited for the interested reader [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. Facile modifications of thrombelastographic methodologies that allow the assessment of changes in fibrinogen include using either antibodies to block platelet receptor glycoprotein IIb/IIIa to prevent attachment that forms fibrin polymers in whole blood [ 35 ], inhibiting the degranulation and formation of the glycoprotein IIb/IIIa by inhibiting microtubular activity with cytochalasin D [ 34 , 35 , 36 ], or by separating plasma in sodium citrate-anticoagulated whole blood [ 33 ].…”

The use of rotational thromboelastometry to guide management followingBitis nasicornisenvenoming

“…ROTEM can undoubtedly detect more subtle signs of deranged coagulation than standard laboratory assessments of coagulation and may enable a more rapid and frequent assessment of coagulation disturbance (if available). However, the clinical significance of such findings is not yet clear, and the risk of antivenom administration should not be forgotten; Tambwe et al used an abnormal ROTEM to guide repeat antivenom administration for one patient despite normal standard coagulation tests which resulted in a significant reaction 26. Severe reactions may occur with many antivenoms, depending on the manufacturer 19…”

Approach to the diagnosis and management of snakebite envenomation in South Africa in humans.

“…It may also assist in evaluating the effectiveness of antivenom, and guide adding further doses. [18] It will guide the use of plasma products, cryoprecipitate and platelet concentrations. Heparin and antifibrinolytic agents (such as tranexamic acid) should not be given.…”