Effect of Hot Saline Irrigation on the Operative Field During Endoscopic Sinus Surgery

INTRODUCTION: Chronic rhinosinsusitis is an inflammatory disease of the sinonasal mucosa lasting for more than 12 weeks. Endoscopic sinus surgery is the surgical procedure used to treat recalcitrant chronic rhinosinusitis. It not only helps in the drainage of sinuses and removal of pathology but also prevents the disturbance of anatomy and formation of facial scars. Control of bleeding during the procedure is a test for surgeons as well as anesthetists. Capillaries are the commonest vessels to bleed during the surgery so that's why mean arterial pressure is an important determinant of the severity of bleeding. A good control of bleeding gives a good visualization of the anatomy during the procedure.

There are different ways to reduce bleeding but all carry side effects too. Topical vasoconstrictors may also be absorbed systemically so must be used carefully in children and patients with cardiac ischemia. Moreover, there's no accurate way to measure absorption of a vasoconstrictor so it's difficult to recommend a safe dose for a particular patient. Cautery which is used to seal blood vessels is also associated with pain as well as mucosal damage. Anesthesia induced hypotension is also not appropriate for all patients as it results in decreased oxygen supply to various vitals organs of the body.

Normal saline heated up to 50°C causes dilatation of vessels and nasal edema without causing nasal mucosa necrosis. This edema compresses blood vessels and helps in controlling bleeding. It also promotes the clotting cascade. In addition, it provides better visualization of the surgical field by reduction of fog formation. A study conducted by Shehata A et al. showed a significant improvement in the operative field when normal saline at 50° C was used during endoscopic sinus surgery. Not only the operative filed was improved, also the duration of surgery was significantly reduced. According to the results of this study, saline heated up to 50°C used for the irrigation of endoscopic sinus surgery produced a result comparable to usage of tranexamic acid with a significant p value. Another study by Ranford D et al. concluded that irrigation with heated saline during endoscopic sinus surgery reduced bleeding by 20 percent.

This study aims to assess the effect of heated normal saline up to 50°C upon the operative field during endoscopic sinus surgery. The use of hot saline for irrigation during endoscopic sinus surgery can prove to be a cost effective method to have a bloodless field during surgery.

METHODS AND MATERIALS:

This randomized controlled trial was conducted after approval from the ethical board in the setting of department of ENT and head \& neck surgery, Benazir Bhutto Hospital, Rawalpindi over a period of ten months from June 2023 to Dec 2023. The sampling technique was simple random sampling. The patients were divided into two groups (treatment group and control group) via randomization using the lottery method. Sample size came out to be 60, with 30 patients in each group. Proper written consents taken from the patients and the surgery was done in the ENT operation theatre by a surgeon with an experience of more than 5 years.

Patient with bilateral chronic rhinosinusitis and pansinusitis on plain CT scan nose and paranasal sinuses were included in the study. Patients with unilateral disease, uncontrolled hypertension, diabetes or other significant comorbidities were excluded. Moreover, patients with the suspicion of malignancy, CSF leak and bleeding diathesis affecting the results were also not included in the study. Group A was the interventional group in which normal saline heated up to 50°C was irrigated during surgery. Normal saline was heated in a boiler and a temperature of 50°C was continuously maintained and monitored. Mean arterial pressure appropriate for endoscopic sinus surgery was controlled by the anesthetist using different drugs for hypotensive anesthesia and it was recorded after every 15 minutes. Intra-operative blood loss was measured from the glass suction tank after subtraction of the irrigated normal saline.

The patient, operating surgeon and primary investigator were blinded during the study to prevent bias. To assess the operative field, subjective grading was done by the surgeon using the Boezaart score. Wait and watch approach was followed to assess bleeding control. Total duration of surgery was also recorded. At the end of the surgery, bilateral anterior nasal packing was done.

ANALYSIS PLAN:

The data was analysed by SPSS version 26. Quantitative data was expressed as mean and standard deviation. Qualitative data was represented as frequencies and percentages. Independent sample T tests was used for the quantitative data analysis. Moreover different correlations were done via Spearman and Kendall test. A P value of <0.05 was considered as significant and a P value of <0.001 showed a high significance.