Rowan Valentine

The efficacy of a novel chitosan gel on hemostasis and wound healing after endoscopic sinus surgery.

Background Postoperative bleeding and adhesion formation are the two most common complications after endoscopic sinus surgery (ESS). Continued bleeding risks airway compromise from the inhalation of blood clots and from the aspiration of blood-stained vomitus. Additionally, adhesion formation is the most common reason for patients requiring revision surgery. This study aimed to determine the efficacy of a novel chitosan/dextran (CD) gel on hemostasis and wound healing after ESS. Methods A randomized controlled trial was performed involving 40 patients undergoing ESS for chronic rhinosinusitis. Immediately after surgery a baseline Boezaart Surgical Field Grading Scale was taken. Computer randomization was performed with one side receiving CD gel and the other side receiving no treatment (control). Boezaart bleeding scores were then calculated for each side every 2 minutes. Patients endoscopic features of wound healing were assessed at 2, 6, and 12 weeks after surgery. Results CD gel achieved rapid hemostasis with the mean time to hemostasis at 2 minutes (95% CI, 2–4 minutes) compared with 10 minutes (95% CI, ≥6 minutes) for the control (p < 0.001). There were significantly less adhesions at all time points with CD gel versus control: 2 versus 18 at 2 weeks (p < 0.001), 3 versus 16 at 6 weeks (p < 0.001), and 2 versus 12 at 3 months (p < 0.001). There was no significant difference between CD gel and control with respect to crusting, mucosal edema, infection, or granulation tissue formation. Conclusions CD gel is rapidly hemostatic immediately after ESS and prevents adhesion formation, addressing two of the most common complications of sinus surgery.

Carotid Artery Injury After Endonasal Surgery

Carotid artery injury during endonasal surgery is the most feared and catastrophic complication. Internal carotid artery injury is more frequent during skull base surgery, and risk factors include acromegaly, previous revision surgery, and prior radiotherapy and bromocriptine therapy. Nasal packing is frequently used to gain hemostasis, often resulting in vascular occlusion. Recent research recommends the crushed muscle patch treatment as an effect hemostat that maintains vascular patency. Endovascular techniques are recommended for vascular control and complication management. Coil or balloon embolization is preferred in patients with adequate collateral cerebral blood flow, and stent-graft placement or bypass surgery is indicated in those who do not.

Controlling the surgical field during a large endoscopic vascular injury.

Since the advent of endonasal skull base surgery, internal carotid artery (ICA) injury has been considered the most dramatic and challenging intraoperative complication. A large vascular injury creates an immediately challenging surgical scenario with rapid blood loss that may result in exsanguination of the patient. Recently we have developed an animal model of the endoscopic, endonasal vascular injury. We describe important surgical steps required in managing the surgical field during a catastrophic vascular event.

The efficacy of hemostatic techniques in the sheep model of carotid artery injury

The most dramatic complication in endonasal surgery is inadvertent injury to the internal carotid artery (ICA) with massive bleeding. Nasal packing is the favored technique for control; however, this often causes complete carotid occlusion or carotid stenosis, contributing to the morbidity and mortality of the patient. The aim of this study is to compare the efficacy of endoscopically applied hemostatic techniques that maintain vascular flow in an animal model of carotid artery injury.

Advances in Absorbable Biomaterials and Nasal Packing

Absorbable biomaterials are commonly used after endoscopic sinus surgery, both for hemostatic and wound healing considerations. Although removable nasal packing is the traditional method of controlling ongoing bleeding and modulating wound healing, it is uncomfortable for patients and associated with several complications. Currently available absorbable agents frequently incite an inflammatory reaction and have been shown in animal and human trials to adversely affect the wound healing process. Newer agents offer distinct advantages because of their unique composition and rapid clearance profiles. The selection of packing material used in any given sinus procedure should be based on surgeon preference and the details of the specific case.

A prospective controlled trial of pulsed nasal nebulizer in maximally dissected cadavers.

Background Nasal douching is common practice in treatment of chronic sinusitis and after endoscopic sinus surgery. Current nasal delivery techniques show inconsistent sinus penetration. The aim of this study was to compare sinonasal penetration of nasal douching to an optimized nasal nebulizer in an operated cadaver model. Methods Fourteen preserved cadavers were used receiving complete sphenoethmoidectomies with a Draf III, wide maxillary antrostomy, or medial maxillectomy. Seven control cadavers received nasal douching with one standardized squeeze bilaterally of a 200-mL nasal irrigation bottle and seven intervention cadavers were nebulized with 3 minutes of the PARI sinus device bilaterally. Douching solutions were stained with methylene blue. Independent observers documented sinonasal anatomy, staining intensity, and percentage area covered by dye using standardized grading protocols. Results Combined data showed a significant increase in intensity of stain (2.06 versus 0.26, p < 0.001), percentage of stain (49.96% versus 4.19%, p < 0.001), and circumference stained (76.59% versus 12.7%, p < 0.001) with the plastic nasal irrigation squeeze bottle versus PARI device. Analysis of individual sinuses consistently showed significant increases in indices of nasal douching relative to nebulization. The PARI sinus nebulizer was noted to reach the ethmoids regularly (92% incidence), whereas the other sinuses were not reached as regularly with incidences noted at frontal (43%), maxillary (46%), and sphenoid (54%). This compares to 96% of all sinuses being stained by the squeeze bottle. Conclusion In all measured indices, the nasal douching method with the squeeze bottle was superior to the PARI sinus nebulizer in highly dissected sinonasal cadaver models.

Nasal dressings after endoscopic sinus surgery: what and why?

Purpose of reviewNasal dressings are commonly used following endoscopic sinus surgery in an attempt to prevent ongoing bleeding and to modulate the wound healing process. Experience with nasal dressings in the otolaryngologic literature spans more than half a century; however, despite this, there is still little agreement between surgeons on the optimal choice of nasal dressings following endoscopic sinus surgery, or whether nasal dressings are required at all. This paper briefly reviews the past research and examines recent advances in the area of nasal dressings. Recent findingsThe ideal nasal dressing is one that is absorbable, hemostatic and improves healing. Although a number of currently available materials may address one of these features, none address all. Currently available dressings that achieve hemostasis worsen wound healing outcomes. However, recent research shows promise with microporous polysaccharide hemospheres and chitosan gel having promising effects on hemostasis, and chitosan gel showing a significant adhesion prevention effect. SummaryThe sinus surgeon must be aware of the potential advantages and limitations of currently available nasal dressings. The area of wound healing and adhesion prevention remains an area of active research and more prospective controlled trials are needed to define any benefits biomaterials may have.

A sheep model to investigate the role of fungal biofilms in sinusitis: fungal and bacterial synergy.

The role of fungi in the spectrum of chronic rhinosinusitis (CRS) is poorly understood. Fungal biofilms have recently been discovered in CRS patients. We have developed an animal model for the investigation of sinonasal fungal biofilms. The role of type I hypersensitivity and pathogenic bacteria is presented.

The efficacy of a novel chitosan gel on hemostasis after endoscopic sinus surgery in a sheep model of chronic rhinosinusitis.

Background Postoperative bleeding remains a major problem after endoscopic sinus surgery (ESS). Patients who continue to bleed after ESS are at risk of airway compromise from inhalation of blood clots or from aspiration of blood-stained vomitus. The aim of this study was to determine the in vivo efficacy of a novel gel on hemostasis after ESS in a sheep model of chronic rhinosinusitis. Methods Twenty-one sheep infested with Oestrus ovus underwent ESS with standardized mucosal injuries created at the anterior ethmoid region using a microdebrider. Immediately after injury a baseline bleeding time was taken using the Boezaart Surgical Field Grading Scale. Computer randomization was performed to either receive chitosan/dextran (CD) gel or no treatment (control). Boezaart bleeding scores were calculated for each side every 2 minutes. Each postoperative day videoendoscopy was performed to document crusting/CD gel dissolution. Results The CD gel side was significantly more hemostatic at 2, 4, and 6 minutes after injury. Average time to hemostasis was significantly better for the intervention side versus control side, 4.09 (±1.61) versus 6.57 (±2.20), respectively (p = 0.049). Complete hemostasis occurred by 6 minutes for all CD gel sides; however, control side bleeding was noted on three sides at 8 minutes and on one side at 10 minutes. There was no significant difference in crusts scores at days 1, 3, 7, and 14. Conclusion In the sheep model of ESS, CD gel significantly improved hemostasis compared with the control at 2, 4, and 6 minutes after mucosal injury.

A blinded randomized controlled trial evaluating the efficacy of chitosan gel on ostial stenosis following endoscopic sinus surgery

Stenosis of sinus ostia following endoscopic sinus surgery (ESS) is the most common reason for revision surgery. Chitosan‐dextran (CD) gel has been shown to be an effective hemostatic agent; however, its effects on ostial stenosis are unknown. This study aims to quantify the effect of CD gel on circumferential scarring following ESS.