title: Comparative safety and efficacy of topical hemostatic agents in a rat neurosurgical model.
abstract: OBJECTIVE
  Adequate hemostasis is extremely important in neurosurgery, commonly requiring the use of topical hemostatic agents. Apart from variable efficacy, the residual presence of these agents may cause foreign body reaction, infection, and delayed bone growth. This study compares the safety and efficacy of commonly used agents with a newly approved agent, Arista (microporous polysaccharide hemospheres; Medafor, Inc., Minneapolis, MN).
  
  
  METHODS
  A brain tissue defect was created in 228 Wistar outbred rats, and either no agent (negative control), Arista, Surgicel (oxidized cellulose; Ethicon, Inc., Somerville, NJ), Avitene (microfibrillar collagen; Alcon, Inc., Humacao, PR), FloSeal (gelatin matrix thrombin sealant; Baxter Healthcare Corp., Deerfield, IL), or kaolin (positive control) was implanted. Time to hemostasis was documented. The animals were sacrificed at different intervals up to 28 days, and presence of residual material and foreign body reaction was determined.
  
  
  RESULTS
  Arista, Avitene, FloSeal, and Surgicel performed better (defined as complete hemostasis within 1 minute) than control (no treatment). Residual material was not present at any time with Arista, markedly contrasting with the presence of residual material in 100% of lesions in the Avitene, FloSeal, and Surgicel groups on Day 14. Avitene and FloSeal also demonstrated a propensity for causing granuloma formation, whereas Arista and Surgicel showed no such evidence.
  
  
  CONCLUSIONS
  Each of these hemostatic agents was effective in controlling bleeding in the majority of standardized neurosurgical lesions. Arista degrades more rapidly than Surgicel, Avitene, and FloSeal and does not result in any foreign body reaction.
authors.affiliation: Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA. ereth.mark@mayo.edu
authors.forename: Mark H
authors.initials: MH
authors.lastname: Ereth
authors.forename: Matthew
authors.initials: M
authors.lastname: Schaff
authors.forename: Eric F
authors.initials: EF
authors.lastname: Ericson
authors.forename: Nicholas M
authors.initials: NM
authors.lastname: Wetjen
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Nuttall
authors.forename: William C
authors.initials: WC
authors.lastname: Oliver
mesh_terms: D000287:Administration, Topical; D000818:Animals; D001930:Brain Injuries / Q000097:blood / Q000601:surgery*; D002483:Cellulose, Oxidized / Q000008:administration & dosage / Q000009:adverse effects; D003094:Collagen / Q000008:administration & dosage / Q000009:adverse effects; D004195:Disease Models, Animal; D005549:Foreign-Body Reaction / Q000139:chemically induced; D005781:Gelatin Sponge, Absorbable / Q000008:administration & dosage / Q000009:adverse effects; D006487:Hemostasis / Q000187:drug effects*; D006490:Hemostatics / Q000008:administration & dosage* / Q000009:adverse effects; D019635:Neurosurgical Procedures / Q000009:adverse effects; D051381:Rats; D013213:Starch / Q000008:administration & dosage* / Q000009:adverse effects; D015996:Survival Rate; D013997:Time Factors
chemical_list: C527600:Arista; D002483:Cellulose, Oxidized; C411004:FloSeal Matrix; D006490:Hemostatics; C013695:Surgicel; D013213:Starch; D003094:Collagen