Arista AH — Microporous Polysaccharide Hemospheres
Arista AH is a plant-starch-derived hemostatic powder composed of microporous polysaccharide hemospheres (MPH). The agent works by rapidly absorbing water and small molecules from blood, concentrating platelets, red cells, and clotting factors onto the matrix surface to accelerate natural clot formation. Unlike Surgicel, Arista is fully resorbed within 24–48 hours by enzymatic degradation — leaving no persistent foreign body.[1]
Mechanism
- Hydrophilic polysaccharide spheres absorb ~1–2× their weight in water from blood within seconds
- Water absorption concentrates platelets, red cells, and clotting factors against the matrix surface
- The concentrated environment accelerates fibrin formation
- Matrix enzymatically degrades within 24–48 hours — rapid resorption
- No persistent foreign body at postoperative imaging or reoperation
- Non-thrombogenic after resorption
Like Surgicel, Arista is a passive matrix — efficacy depends on native clotting function.
Distinctive Features vs. Other Matrices
| Feature | Arista AH | Surgicel | Gelfoam |
|---|---|---|---|
| Source | Plant starch (polysaccharide) | Plant cellulose | Porcine gelatin |
| Time to resorption | 24–48 hours | 7–14 days | 4–6 weeks |
| Foreign body granuloma risk | Very low | Moderate | Moderate |
| Form | Powder | Fabric / fibril / powder | Sponge / flowable |
| Acidic microenvironment | No (neutral) | Yes (low pH) | No (neutral) |
The rapid resorption is Arista's distinguishing advantage — no long-term foreign body, no granuloma on follow-up imaging, no stone nidus in urinary-tract-adjacent placement.
GU Applications
- Diffuse renal-bed oozing after partial nephrectomy
- Pelvic sidewall after lymphadenectomy
- Flap donor-bed oozing (gracilis, ALT, VRAM)
- Buccal mucosa donor site — brief tamponade without persistent foreign body in the oral cavity
- Scrotal / perineal bleeding after Fournier's debridement
- Urinary tract-adjacent placement — Arista's rapid resorption makes it preferred over Surgicel when the hemostatic matrix may contact or be adjacent to urinary collecting system or bladder mucosa
Application Technique
- Dry the field — Arista works by absorbing fluid, so a pooled field is less effective
- Sprinkle powder over the oozing surface — the bellows-delivery device (supplied with product) distributes evenly
- Apply gentle pressure with a dry sponge for 1–3 minutes
- Do not wipe — let the coagulum consolidate
- Excess can be removed with gentle suction if over-applied; no specific wash step required
Advantages
- No persistent foreign body at 48 hours — important in urinary-tract surgery, infected fields, and any case where future imaging is planned
- Plant-derived — no animal or human blood-product source; suitable for patients with religious restrictions on animal products
- Non-immunogenic
- Fast preparation — powder ready to use, no reconstitution
- Cost effective for routine oozing (cheaper than FloSeal, similar to Surgicel)
Limitations
- Passive only — ineffective against rapid arterial bleeding
- Reduced efficacy in severe coagulopathy / heparinization
- Powder can blow around in the surgical field — aim carefully, especially in laparoscopic cases where the pneumoperitoneum can disperse the powder
- Not as effective as FloSeal for venous / broad surface bleeding in anticoagulated patients
See Also
References
1. Tschan CA, Nieman F, Oertel J. Hemostatic agents in spine surgery. J Neurol Surg A Cent Eur Neurosurg. 2014;75(6):500–3. doi:10.1055/s-0034-1371511