title: Comparison of green pit viper and Agkistrodon halys antivenom in inhibition of coagulopathy due to Trimeresurus albolabris venom: an in-vitro study using human plasma.
abstract: BACKGROUND
  There are two antivenoms that may be administered in Hong Kong following a bite by Trimeresurus albolabris: the green pit viper antivenom from the Thai Red Cross Society in Thailand and the Agkistrodon halys antivenom from the Shanghai Institute of Biological Products in China. Both are recommended by the Central Coordinating Committee of Accident and Emergency Services of the Hospital Authority for treating patients with a bite by Trimeresurus albolabris. The choice of which antivenom to use is based on physician preference. This study aimed to compare the relative efficacy of the two antivenoms.
  
  
  METHODS
  This in-vitro experimental study was carried out by a wildlife conservation organisation and a regional hospital in Hong Kong. Human plasma from 40 adult health care worker volunteers was collected. The Trimeresurus albolabris venom was added to human plasma and the mixture was assayed after incubation with each antivenom (green pit viper and Agkistrodon halys) using saline as a control. Fibrinogen level and clotting time in both antivenom groups were studied.
  
  
  RESULTS
  The mean fibrinogen level was elevated from 0 g/L to 2.86 g/L and 1.11 g/L after the addition of green pit viper antivenom and Agkistrodon halys antivenom, respectively. When mean clotting time was measured, the value was 6.70 minutes in the control, prolonged to more than 360 minutes by green pit viper antivenom and to 19.06 minutes by Agkistrodon halys antivenom.
  
  
  CONCLUSIONS
  Green pit viper antivenom was superior to Agkistrodon halys antivenom in neutralisation of the thrombin-like and hypofibrinogenaemic activities of Trimeresurus albolabris venom.
authors.affiliation: Department of Accident and Emergency, Tuen Mun Hospital, Tuen Mun, Hong Kong.
authors.forename: S K
authors.initials: SK
authors.lastname: Lam
authors.affiliation: Department of Pathology and Department of Medicine and Geriatrics, Tuen Mun Hospital, Tuen Mun, Hong Kong.
authors.forename: S F
authors.initials: SF
authors.lastname: Yip
authors.affiliation: Fauna Conservation Department, Kadoorie Farm and Botanic Garden, Tai Po, Hong Kong.
authors.forename: P
authors.initials: P
authors.lastname: Crow
authors.affiliation: Department of Accident and Emergency, Tuen Mun Hospital, Tuen Mun, Hong Kong.
authors.forename: H T
authors.initials: HT
authors.lastname: Fung
authors.affiliation: Department of Pathology, Tuen Mun Hospital, Tuen Mun, Hong Kong.
authors.forename: J Mh
authors.initials: JM
authors.lastname: Cheng
authors.affiliation: Fauna Conservation Department, Kadoorie Farm and Botanic Garden, Tai Po, Hong Kong.
authors.forename: K S
authors.initials: KS
authors.lastname: Tan
authors.affiliation: Department of Accident and Emergency, North Lantau Hospital, Lantau, Hong Kong.
authors.forename: O F
authors.initials: OF
authors.lastname: Wong
authors.affiliation: Department of Pathology, Tuen Mun Hospital, Tuen Mun, Hong Kong.
authors.forename: D Yt
authors.initials: DY
authors.lastname: Yeung
authors.affiliation: Fauna Conservation Department, Kadoorie Farm and Botanic Garden, Tai Po, Hong Kong.
authors.forename: Y K
authors.initials: YK
authors.lastname: Wong
authors.affiliation: Department of Accident and Emergency, Tuen Mun Hospital, Tuen Mun, Hong Kong.
authors.forename: K M
authors.initials: KM
authors.lastname: Poon
authors.affiliation: Fauna Conservation Department, Kadoorie Farm and Botanic Garden, Tai Po, Hong Kong.
authors.forename: G
authors.initials: G
authors.lastname: Ades
mesh_terms: D000328:Adult; D000997:Antivenins / Q000494:pharmacology*; D001777:Blood Coagulation / Q000187:drug effects*; D001780:Blood Coagulation Tests; D002681:China; D003435:Crotalid Venoms / Q000037:antagonists & inhibitors* / Q000506:poisoning; D064368:Healthy Volunteers; D006723:Hong Kong; D006801:Humans; D012909:Snake Bites / Q000628:therapy; D013785:Thailand; D013997:Time Factors
chemical_list: C031442:Agkistrodon venoms; D000997:Antivenins; D003435:Crotalid Venoms
keywords: Antivenins; Humans; Plasma; Snake bites; Trimeresurus