Topical Hemostatic Biomaterials

Mechanism

Pharmacological Class and Group

Medical devices and hemostatic biomaterials with local physical-chemical action of absorbable or non-absorbable type for intranasal or otic use.

Mechanism of Action

They act by triggering the local physiological coagulation cascade by stimulating platelet aggregation or physical absorption of fluids:

• Oxidized Regenerated Cellulose (Surgicel): Upon direct contact with blood in the nasal cavity or surgical bed, it absorbs free plasma and swells immediately, transforming into a brownish-black gelatinous mass with a local acidic pH:
  • The local acid mass acts as a physical scaffold that promotes rapid platelet adhesion and degranulation.
  • The acidic pH of free cellulose exerts a mild local antimicrobial effect, preventing superinfections.
• Absorbable Gelatin Sponge (Gelfoam/Spongostan): Physical porous matrix that absorbs up to 40 times its weight in blood fluids:
  • Upon swelling, the pores of the gelatin physically retain the platelets inside, inducing their degranulation and the release of platelet activating factors through direct capillary stasis, favoring the formation of a dense network of insoluble fibrin.
• High Density Polyvinyl Alcohol (Merocel): Expandable non-absorbable plug with high physical resistance:
  • When it comes into contact with physiological solution or blood, its hydrophilic pores absorb liquid, expanding progressively until it fills the entire nasal cavity.
  • Exerts uniform and direct mechanical hydrostatic pressure against the walls of the nasal fossa and turbinates, physically collapsing the bleeding arterioles of the septum and turbinate.

Synergistic Mechanism of Physical Expansion and Compression

Merocel + Blood Capillary volumetric expansion Direct compression of the Kiesselbach plexus Surgicel + Blood Acidic pH gel formation Local platelet activation

While oxidized regenerated cellulose undergoes spontaneous biological degradation (reabsorption in 7-14 days), polyvinyl alcohol requires manual physical removal of instruments by the consulting specialist (usually 48-72 hours after placement), requiring abundant lubrication to avoid mechanical tearing of the clot formed.

Pharmacokinetics

High Resolution Pharmacokinetics and Biodegradation

• Oxidized Regenerated Cellulose: Complete tissue enzymatic cellular absorption and digestion in a period of 7 to 14 days without generating a significant foreign body response.
• Biodegradable Polyurethane (Nasopore): Spontaneous physical fragmentation due to the action of humidity and nasal secretion within a period of 5 to 7 days, draining in the form of fluid mucus, without the need for instrumental physical removal by the otorhinolaryngologist.
• Polyvinyl Alcohol: Not biodegradable. It requires mandatory manual removal in consultation within a period of 48 to 72 hours to prevent the risk of tissue necrosis due to pressure or septic shock.

Indicators and dose

Clinical Indications and Off-Label Uses

• Previous Nasal Packing in Severe Epistaxis: Immediate control of nosebleeds that do not respond to cauterization with silver nitrate or bipolar (Merocel/Nasopore).
• Postoperative Support and Hemostasis in Nasosinusal Surgery (Septoplasty, FESS): To avoid the collapse of the nasal turbinates, stabilize the cartilaginous septum in the midline, prevent synechiae and control local capillary bleeding from the open ethmoidal cells (Nasopore/Surgicel).
• Hemostasis of the external auditory canal or tympanic cavity (off-label): Control of capillary bleeding after tympanoplasty or mastoidectomy (Gelfoam).

Dosage and Clinical Application

Previous Nasal Packing with Polyvinyl Alcohol (Merocel):

• Insert the lubricated plug (with antibiotic ointment or saline solution) horizontally along the floor of the nasal cavity, sliding parallel to the middle septum.
• Moisten once inserted with 5-10 mL of sterile saline to induce immediate mechanical volumetric expansion.
• Retention Limit: Mandatory withdrawal in consultation within a maximum period of 48 to 72 hours. Oral systemic antibiotic prophylaxis (Amoxicillin/Clavulanate) should be associated to prevent the development of septic shock.

Absorbable Hemostasis with Oxidized Regenerated Cellulose (Surgicel):

• Apply a small strip adapted to the size of the bleeding vessel to the turbinate or Kiesselbach's plexus after cauterizing.
• Physical removal is not necessary; It will be reabsorbed spontaneously within 7 to 14 days.

Security

Absolute and Relative Contraindications

Absolute Contraindications

• Hypersensitivity to the material or excipients in the formulation (e.g., allergy to porcine gelatin in Gelfoam).
• Suppurative bacterial infections of the nasal passage without basic antimicrobial treatment.
• Use of Surgicel to control bleeding near the optic nerve or optic foramen in FESS (the swelling of the material in closed bone spaces can induce ischemic compression of the optic nerve).

Relative Contraindications

• Previous wide septal perforations (bilateral rigid tamponade may further compromise capillary flow of the anterior septum).

Adverse Effects (ADR) and Specific Toxicity

• Frequent (1%-10%): Diffuse oppressive nasal pain, tension headache secondary to compression of the turbinates, oropharyngeal dryness due to forced mouth breathing, reflex sneezing.
• Uncommon (0.1%-1%): Nasal synechiae (mucosal adhesions between the turbinate and septum due to abnormal scarring), immediate recurrent bleeding upon mechanical removal of the non-absorbable plug.
• Rare (<0.1%): Septic Shock Syndrome (SSS) (due to massive proliferation and invasion of Staphylococcus aureus toxins in prolonged nasal packing for more than 72 hours), nasal vestibulitis, acute obstructive rhinosinusitis.

Critical Toxicity: Septic Shock Syndrome due to Prolonged Nasal Packing

The stagnation of blood and mucus in a nasal passage completely occluded by a tamponade of polyvinyl alcohol (Merocel) or other non-resorbable materials for more than 48-72 hours, provides an optimal culture medium for the accelerated proliferation of strains producing the Septic Shock Syndrome toxin-1 (TSST-1) of Staphylococcus aureus. The condition manifests abruptly with very high fever, generalized erythematous skin rash that mimics sunburn, profound arterial hypotension refractory to fluids, mental confusion and multiple organ failure.

Prolonged tamponade > 48h Procreation of S. aureus Release of TSST-1 and Septic Shock

It is mandatory to remove the packing immediately, perform nasal cultures, and initiate emergency support in the ICU with massive volume replacement and antibiotic therapy with specific anti-staphylococcal coverage (Cloxacillin or Linezolid) to stabilize the patient.

Interactions with other Devices or Drugs

• It is advisable to moisten and lubricate the polyvinyl alcohol tamponade with plenty of saline solution and even topical antibiotic/corticosteroid drops before removal to avoid physical adhesion to the clot and epithelial tear.
• Dense Vaseline ointments should not be associated with Surgicel, since they can inactivate the physical swelling mechanism of the material due to lipid exclusion from plasma water.

Safety in Pregnancy and Breastfeeding

• Pregnancy: Absolutely compatible due to the physical nature of the local treatment, considering mechanical tamponade of first choice in refractory gestational epistaxis.
• Breastfeeding: Compatible. It does not represent a risk of absorption or adverse effects for the full-term infant.