Pre-operative nasal probe tests with adrenaline and lidocaine ease insertion during flexible bronchoscopy and reduce post-operative bleeding:a randomized controlled trial

Background:Nasal insertion is the preferred method for non-intubated patients in flexible bronchoscopy;however,the relatively narrow nasal cavity results in difficulties related to bronchoscope insertion.This study aimed to investigate whether pre-operative nasal probe tests could reduce the time to pass the glottis,improve the first-pass success rate and patients’tolerance,and reduce postoperative bleeding.Methods:This three-arm prospective randomized controlled trial was conducted in a tertiary hospital between May and October 2020.Three hundred patients requiring diagnosis and treatment using flexible bronchoscopy were randomly allocated to three groups:control group,simple cotton bud detection group(CD group),and adrenaline+lidocaine detection group(AD group).The primary outcome was the time to pass the glottis.Secondary outcomes included the first-pass success rate,the patients’tolerance scores,and post-operative bleeding.One-way analysis of variance,Kruskal-WallisH test,Chi-squared test,Fisher’s exact test,and Bonferroni’s multiple comparison tests were used in this study.Results:In total,189 men and 111 women were enrolled in this study,with a mean age of 55.72±12.86 years.The insertion time was significantly shorter in the AD group than in the control group(18.00 s[12.00–26.50 s]vs.24.00 s[14.50–45.50 s],P=0.005).Both the AD(99%vs.83%,χ2=15.62,P<0.001)and CD groups(94%vs.83%,χ2=5.94,P=0.015)had a significantly higher first-pass success rate than the control group.Compared with the control group,post-operative bleeding(1%vs.13%,χ2=11.06,P<0.001)was significantly lower in the AD group.However,no significant difference was found in the patients’tolerance scores.Conclusions:Pre-operative nasal cavity probe tests especially with adrenaline and lidocaine during flexible bronchoscopy can significantly reduce the time to pass the glottis,improve the first-pass success rate,and reduce post-operative nasal bleeding.Pre-operative nasal probe tests are recommended as a time-saving procedure for patients undergoing flexible bronchoscopy.Trial registration:Chinese Clinical Trial Registry(ChiCTR),ChiCTR2000032668;http://www.chictr.org.cn/showprojen.aspx?proj=53321.