Comparison of regenerated and non-regenerated oxidized cellulose hemostatic agents

Abstract

Background: Oxidized cellulose is a well known and widely used surgical hemostat. It is available in many forms, but manufactured using either a nonregenerated or regenerated process.

Objective: This study compares the fiber structure, pH in solution, bactericidal effectiveness, and hemostatic effectiveness of an oxidized nonregenerated cellulose (ONRC; Traumastem^®) and an oxidized regenerated cellulose (ORC; Surgicel^® Original).

Methods: In vitro, fiber structures were compared using scanning electron microscopy, pH of phosphate buffer solution (PBS) and human plasma were measured after each cellulose was submerged, and bactericidal effect was measured by plating each cellulose with four bacteria. In vivo, time to hemostasis and hemostatic success were compared using a general surgery nonheparinized porcine liver abrasion model and a peripheral vascular surgery heparinized leporine femoral vessel bleeding model.

Results: Ultrastructure of ONRC fiber is frayed, while ORC is smooth. ORC pH is statistically more acidic than ONRC in PBS, but equal in plasma. No difference in bactericidal effectiveness was observed. In vivo, ONRC provided superior time to hemostasis relative to ORC (211.2 vs 384.6 s, N = 60/group) in the general surgery model; and superior hemostatic success relative to ORC at 30 (60 vs. 15 %; OR: 13.5; 95 % CI: 3.72-49.1, N = 40/group), 60 (85 vs. 37.5 %; OR: 12.3; 95 % CI: 3.66-41.6), and 90 s (97.5 vs 70.0 %; OR: 21.1, 95 % CI: 2.28-195.9) in the peripheral vascular model.

Conclusion: ONRC provides superior hemostasis and equivalent bactericidal effectiveness relative to ORC, which is likely due to its fiber structure than acidity.

Keywords: Cellulose; Celstat; Fibrin pad; Hemostasis; Liver abrasion; Liver square; Oxidized cellulose; Surgicel; Traumastem.

Fig. 1

Gross and ultrastructural appearance of Traumastem®, a nonregenerated oxidized cellulose (a, c), and Surgicel® Original, a regenerated oxidized cellulose (b, d)

Fig. 2

Bactericidal effect of Traumastem®, non-regenerated oxidized cellulose, and Surgicel® Original, regenerated oxidized cellulose, against a Staphylococcus aureus (ATCC 6538), b Pseudomonas aeruginosa (ATCC 9027), c Streptococcus pyogenes (ATCC 19615), and d Enterococcus faecium (ATCC 6057) relative to a sterile gauze negative control. Time point 0 represents baseline colony forming units (CFUs) prior to treatment

Fig. 3

Box plot of the time to hemostasis in a nonheparinized porcine hepatic square model (N = 60 lesions per group). Traumastem®, a nonregenerated oxidized cellulose, provides superior hemostasis relative to Surgicel® Original, a regenerated oxidized cellulose (* statistical significance based on geometrical mean ratio of 1.857 [95 % CI: 1.669–2.065]). Range, 25th, 50th, and 75th percentiles are depicted

Fig. 4

Representative hepatic square lesions on the lateral aspect of the left lateral lobe treated with Traumastem®, a nonregenerated cellulose (left), and Surgicel® Original, a regenerated cellulose (right); where excess blood loss is observed from the regenerated cellulose treated lesion, while hemostasis is provided by nonregenerated cellulose

Fig. 5

Representative hepatic square lesions treated with Traumastem®, a nonregenerated cellulose (left images), and Surgicel®, a regenerated oxidized cellulose (right images) stained brown with a monoclonal antibody against fibrin (upper images) and the CD62 antigen on platelets (lower images). Images are 10x, insets are 40x. Surgicel® treated lesions have greater fibrin and platelets due to excessive bleeding, while Traumastem® treated lesions have less fibrin and platelets due to faster time to hemostasis. T  Traumastem®, S Surgicel®, L  Liver, F Fibrin, P  Platelets

Fig. 6

Hemostatic success 30, 60, and 90 s after treatment for Traumastem®, a nonregenerated cellulose, and Surgicel® Original, a regenerated cellulose, in a heparinized leporine femoral bleeding model (N = 40 lesions per group). Traumastem® is superior to Surgicel® at all time points based on an odds ratio of success (* 13.5 [95 % CI: 3.72–49.1]; ** 12.3 [3.66–41.6]; *** 21.1 [2.28–195.9])