Nasal dressings have frequently been advocated to improve wound healing and prevent ongoing bleeding after endoscopic sinus surgery (ESS). Initial experience focused on removable nasal packing materials; however, their adverse effect profile, such as pain/discomfort and mucosal trauma, has driven the development of absorbable biomaterials. Despite these developments, there is still little agreement on the optimal choice of nasal dressing or whether nasal dressings are required at all.
Absorbable nasal dressings have been used since 1969, and since this time an array of products have been marketed for their positive effects on hemostasis and wound healing. These products can be broadly divided into synthetic, plant, blood product, or animal product derived materials. Blood or animal derived materials include hemostatic agents such as thrombin and are seen in Fibrin glue (Quixil, Omrix, Brussels, Belgium) and more recently FloSeal (Baxter International, Deerfield, IL). The routine use of blood-based products has the disadvantage of the potential for disease transmission such as human immunodeficiency virus, Creutzfeldt-Jakob disease, and thrombin antibody formation. These disadvantages, however, are not encountered with either plant derived materials or synthetic materials.
A recent review has analyzed the literature with regard to the use of absorbable biomaterials in preventing postoperative bleeding. Weitzel et al. showed that no study favored any particular agent, as studies focused on intervening in all patients following ESS.1 Eliasher et al. investigated 97 consecutive ESS patients, evaluating the routine use of packing or local hemostatic agents.2 Bipolar cautery was used for pulsatile bleeding only. Packing was only used if bleeding continued 5 minutes after completion of surgery. Ninety-two percent (89) of patients did not require packing, and no “no-packing” patients had a postoperative bleed. Only 8% (8) of patients met the criteria for packing (either with Merocel, microfibrillar collagen, or tranexamic acid).2 This suggests that routine use of nasal packing to prevent postoperative bleeding is unnecessary.
The main indication for the routine use of absorbable nasal packing materials is to modulate the wound-healing processes, with adhesion formation the most common complication following ESS, occurring in up to 36% of patients. With regard to traditional agents such as oxidized regenerated cellulose, hyaluronic acid, porcine gelatin/collagen, and mitomycin C, there is currently no randomized controlled trial demonstrating any wound-healing advantages when compared with no treatment at all.1
Over the last few years, a number of new products have been investigated for their effect on wound healing. These products include a gelatin matrix combined with human derived thrombin (FloSeal), a synthetic dissolvable biodegradable polyurethane foam (Nasopore, Stryker Canada, Hamilton, ON, Canada), carboxy-methyl-cellulose (ArthroCare, Glenfield, United Kingdom), and chitosan gel (Department of Chemistry, University of Otago, Dunedin, New Zealand). Chandra et al. investigated the effect of FloSeal on mucosal healing following ESS in 20 patients.3 Each ethmoid cavity was randomized to receive either FloSeal or thrombin-soaked gelfoam. Ethmoid cavities that had received FloSeal had significantly greater adhesions (P = .0004) and granulation tissue formation (P = .004), with follow-up continuing for a mean of 21 months. Biopsies showed that FloSeal was incorporated within the recovering mucosa 25 months later. These adverse results may be explained by the bidirectional relationship between coagulation and inflammation. This effect explains why some biomaterials excel in hemostasis but by activating the clotting cascade also adversely affect the wound-healing processes.
Carboxy-methyl-cellulose (CMC) has been investigated by Kastl et al. in 26 patients.4 Patients were randomized to receive CMC in either the left or right nasal cavity, leaving the opposite side as an untreated control. CMC had no appreciable effect on wound healing when compared with no treatment at all. The authors concluded that the anticipated beneficial effect of nasal packing on wound healing is wishful thinking rather than a clinical reality.
In late 2005 the Food and Drug Administration approved the use of synthetic dissolvable biodegradable polyurethane foam (Nasopore), and recently the wound-healing effects have been investigated. Shoman et al. randomized 30 patients to receive Nasopore on the left or the right, with the opposite cavity receiving a vinyl-gloved Merocel packing.5 Nasopore had a statistically significant adverse affect on mucosal scores postoperatively at 1 month (P = .03). Reassessment at 3 months, however, showed no significant difference or trend between Nasopore-treated vs. Merocel-treated nasal cavities.
Chitosan has long been known to be an effective hemostatic agent that prevents adhesion formation following abdominal and pelvic surgery. Recently this product has been developed to be easily applied after ESS. Following the observation that chitosan gel improves the microscopic features of wound healing in an animal model, Valentine et al. investigated its efficacy on wound healing after ESS.6 This study randomized 40 patients to receive either chitosan gel in the left or right ethmoid cavity postoperatively, with the opposite side acting as the untreated control. Results showed that there were significantly fewer adhesions on the chitosan gel side vs. the control: 2 vs. 12 at 3 months (P ≤ .001). With regard to mucosal scores, however, there was no significant difference with respect to crusting, mucosal oedema, infection, or granulation tissue formation.
The routine use of nasal packing materials to prevent postoperative bleeding events following ESS is unnecessary. A small percentage of patients will require nasal packing for ongoing bleeding after ESS. The use of bipolar cautery, topical vasoconstrictors, or dissolvable packing agents that don't adversely affect wound healing may be used to obtain hemostasis. The literature suggests that the use of dissolvable agents to improve wound healing is largely unfounded and the anticipated beneficial effect of nasal packing is wishful thinking rather than a clinical reality. In some cases the use of dissolvable agents actually has an adverse effect on the wound-healing processes. There is no commercially available product that improves wound healing when compared with no treatment at all. Research indicates that chitosan may be of benefit, but further independent research is required before recommendations can be made.
LEVEL OF EVIDENCE
The literature analyzed in this review relate to level 1 evidence (randomized controlled trials).