Abstract
Statement of problem
The aim of this study was to evaluate the efficacy of lidocaine spray 10%, compared with tetracaine 2% solution, as a local anesthetic for patients undergoing transnasal fiber-optic laryngoscopy.
Method of study
A prospective study was conducted on patients undergoing transnasal fiber-optic laryngoscopy. Microsurgical sponges were applied in each side of the nose for 10 minutes before laryngoscopy. Patients were randomly classified into group A and group B, in which tetracaine 2% solution and lidocaine spray 10% were used, respectively. Patients were asked to evaluate the severity of pain during the procedure by a visual analog scale. Patients data, pain score, and potential complications were placed in a database and statistically assessed.
Main results
Our series consisted of 48 patients. Statistical analysis showed significant lower mean nasal discomfort score in favor of the tetracaine group (2.29 vs 3.04 [ P < .001]). No tetracaine complications or side effects occurred.
Principal conclusion
Neurosurgical sponge application of tetracaine 2% solution is an easy, safe, inexpensive, and effective analgesia for transnasal fiber-optic laryngoscopy.
1
Introduction
Laryngeal examination on patients is traditionally performed under indirect mirror laryngoscopy. An accurate diagnosis might be inadequate when patient gagging does not permit sufficient visualization. Mirror laryngoscopy is not always practical due to gagging and unnatural position of the larynx during the examination. The anatomy of the nasal passages, pharynx, and larynx and evaluation of laryngeal function is well observed by transnasal fiber-optic laryngoscopy (TFL) first introduced by Sawashima and Hirose in 1968.
Lidocaine and tetracaine are commonly used as topical anesthetics. Previous studies concerning the practice of topical nasal anesthesia before TFL have concluded that its use does not improve patient comfort during examination . Often, an examination cannot be completed, or it could become marginal in quality due to patient discomfort and agitation of the patients.
Although lidocaine solution has been proposed for local anesthetic to TFL, tetracaine is a very potent and effective ester topic anesthetic, providing long-duration anesthesia. The local intranasal anesthetic effect of tetracaine solution has been already proven superior to that of lidocaine . The purpose of this study was to compare the efficacy of lidocaine spray and tetracaine solution topic anesthetic, in TFL.
2
Materials and methods
A prospective study was conducted between January 2008 and August 2008, on patients undergoing TFL. This study was approved by the local ethic committee, and written informed consent was obtained from all patients before inclusion in the study. All patients were examined by the authors (CB, PT, AG, AK), under topic anesthesia with the same technique. Patients receiving anxiolytic, hypnotic, and antidepressant medication were excluded from the study. Six neurosurgical sponges (60 × 8 mm) were applied in both sides of the nose as depicted in Fig. 1 . The first sponge was inserted under the roof of the nose to anesthetize the branches of the anterior ethmoid nerve. The second was passed across the midportion of the middle turbinate in the region of the sphenopalatine foramen, and the last one was applied over the surface of the inferior turbinate. Subjects were divided into 2 groups. Group A, in which 4 mL of tetracaine 2% solution (total dose, 80 mg) was soaked on the neurosurgical sponges and completely wrung, or group B, in which 3 vaporizations of lidocaine spray 10% in each neurosurgical sponge was used (total dose, 180 mg). Compared dosages were selected on published data on their efficacy ensuring anesthetic effect without reaching toxic levels. In both groups, 2 vaporizations of oxymetazolin spray 0.1% were sprayed on each nasal cavity, before the insertion of the sponges. The neurosurgical sponges had been inserted into the patient’s nose for 10 minutes before the TFL. A flexible transnasal fiber-optic 4.2-mm diameter laryngoscope was used. Two hours after the examination, patients were requested by a junior author (AK) to evaluate the intensity of the pain they experienced during the TFL, using a visual analog scale (range, 0–10, where 0 = no pain and 10 = intolerable pain). Data were statistically assessed by Mann-Whitney U nonparametric test, using the SSPS 12.0 software (SPSS Inc, Chicago, IL).
2
Materials and methods
A prospective study was conducted between January 2008 and August 2008, on patients undergoing TFL. This study was approved by the local ethic committee, and written informed consent was obtained from all patients before inclusion in the study. All patients were examined by the authors (CB, PT, AG, AK), under topic anesthesia with the same technique. Patients receiving anxiolytic, hypnotic, and antidepressant medication were excluded from the study. Six neurosurgical sponges (60 × 8 mm) were applied in both sides of the nose as depicted in Fig. 1 . The first sponge was inserted under the roof of the nose to anesthetize the branches of the anterior ethmoid nerve. The second was passed across the midportion of the middle turbinate in the region of the sphenopalatine foramen, and the last one was applied over the surface of the inferior turbinate. Subjects were divided into 2 groups. Group A, in which 4 mL of tetracaine 2% solution (total dose, 80 mg) was soaked on the neurosurgical sponges and completely wrung, or group B, in which 3 vaporizations of lidocaine spray 10% in each neurosurgical sponge was used (total dose, 180 mg). Compared dosages were selected on published data on their efficacy ensuring anesthetic effect without reaching toxic levels. In both groups, 2 vaporizations of oxymetazolin spray 0.1% were sprayed on each nasal cavity, before the insertion of the sponges. The neurosurgical sponges had been inserted into the patient’s nose for 10 minutes before the TFL. A flexible transnasal fiber-optic 4.2-mm diameter laryngoscope was used. Two hours after the examination, patients were requested by a junior author (AK) to evaluate the intensity of the pain they experienced during the TFL, using a visual analog scale (range, 0–10, where 0 = no pain and 10 = intolerable pain). Data were statistically assessed by Mann-Whitney U nonparametric test, using the SSPS 12.0 software (SPSS Inc, Chicago, IL).
