Preoperative chlorhexidine mouthwash to prevent postoperative infections in low-risk elective abdominal surgeries: a double-blind RCT from North India among patients with poor oral hygiene

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Abstract

INTRODUCTION: Postoperative respiratory complications, particularly in patients with poor oral hygiene, contribute significantly to morbidity and healthcare burden. The oral cavity serves as a reservoir of pathogenic micro-organisms that, when aspirated during or after surgery, can lead to respiratory infections. While chlorhexidine mouthwash has shown promise in high-risk surgeries, its role in short-duration elective abdominal surgeries remains unexplored, especially in low-resource settings. METHODS: This double-blind, randomised controlledrial included 228 patients (American Society of Anaesthesiologists I/II, aged 18-65 years, Oral Hygiene Index (OHI) >6) undergoing elective abdominal surgery under general anaesthesia lasting <4 hours. Patients were randomised to receive either 0.2% chlorhexidine (group A) or normal saline (group B) mouthwash two times before surgery. Outcomes measured included postoperative sore throat, fever, pneumonia, surgical site infections (SSI) and length of hospital stay. Microbiological cultures, complete blood count, C-reactive protein (CRP) and chest X-rays were evaluated on postoperative days 1, 3 and 7. RESULTS: Chlorhexidine significantly reduced sore throat (18.42% vs 47.37%, p<0.001), positive bacterial cultures (21.05% vs 62.28%, p<0.001), CRP elevation and SSI (4.39% vs 21.93%, p<0.001). Length of hospital stay was also shorter in the chlorhexidine group (p<0.001). Pneumonia rates were low and comparable. CONCLUSION: This double-blind randomised controlled trial demonstrates that preoperative use of chlorhexidine mouthwash significantly reduces postoperative sore throat, bacterial colonisation, SSI and length of hospital stay in patients with poor oral hygiene undergoing short-duration elective abdominal surgeries. These findings highlight the utility of a simple, low-cost oral hygiene intervention in improving surgical outcomes, particularly in low-resource settings and support its incorporation into standard perioperative protocols, even for lower risk procedures. TRIAL REGISTRATION NUMBER: CTRI/2024/06/069511).

Abstract as published, via PubMed.