Patient comfort and plasma lignocaine concentrations during fibreoptic bronchoscopy

Influence of Pharyngeal Anaesthesia on Post-Bronchoscopic Coughing: A Prospective, Single Blinded, Multicentre Trial

Background: Local anaesthesia of the pharynx (LAP) was introduced in the era of rigid bronchoscopy (which was initially a conscious procedure under local anaesthetic), and continued into the era of flexible bronchoscopy (FB) in order to facilitate introduction of the FB. LAP reduces cough and gagging reflex, but its post-procedural effect is unclear. This prospective multicentre trial evaluated the effect of LAP on coughing intensity/time and patient comfort after FB, and the feasibility of FB under propofol sedation alone, without LAP. Material and methods: FB was performed in 74 consecutive patients under sedation with propofol, either alone (35 patients, 47.3%) or with additional LAP (39 patients, 52.7%). A primary endpoint of post-procedural coughing duration in the first 10 min after awakening was evaluated. A secondary endpoint was the cough frequency, quality and development of coughing in the same period during the 10 min post-procedure. Finally, the ease of undertaking the FB and the patient’s tolerance and safety were evaluated from the point of view of the investigator, the assistant technician and the patient. Results: We observed a trend to a shorter cumulative coughing time of 48.6 s in the group without LAP compared to 82.8 s in the group receiving LAP within the first 10 min after the procedure, although this difference was not significant (p = 0.24). There was no significant difference in the cough frequency, quality, peri-procedural complication rate, nor patient tolerance or safety. FB, including any additional procedure, could be performed equally well with or without LAP in both groups. Conclusions: Our study suggests that undertaking FB under deep sedation without LAP does to affect post-procedural cough duration and frequency. However, further prospective randomised controlled trials are needed to further support this finding.

Comparison between lignocaine nebulization and airway nerve block for awake fiberoptic bronchoscopy-guided nasotracheal intubation: a single-blind randomized prospective study

BACKGROUND

The preferred management strategy for difficult airways is awake fiberoptic bronchoscopy-guided intubation, which requires effective airway anesthesia to ensure patient comfort and acceptance. This randomized single-blind prospective study was conducted to compare lignocaine nebulization and airway nerve block for airway anesthesia prior to awake fiberoptic bronchoscopy-guided intubation.

METHODS

Sixty adult patients scheduled for surgical procedures under general anesthesia were randomly allocated to two groups. Group N received jet nebulization (10 ml of 4% lignocaine) and Group B received bilateral superior laryngeal and transtracheal recurrent laryngeal nerve blocks (each with 2 ml of 2% lignocaine) followed by fiberoptic bronchoscopy-guided nasotracheal intubation. All patients received procedural sedation with dexmedetomidine. The intubation time, intubating conditions, vocal cord position, cough severity, and degree of patient satisfaction were recorded. Student's t test was used to analyze parametric data, while the Mann-Whitney U test was applied to non-parametric data and Fisher's test to categorical data. P values < 0.05 were considered statistically significant.

RESULTS

The time taken for intubation was significantly shorter in Group B [115.2 (14.7) s compared with Group N [214.0 (22.2) s] (P = 0.029). The intubating conditions and degree of patient comfort were better in Group B compared with Group N. Although all patients were successfully intubated, patient satisfaction was higher in Group B.

CONCLUSIONS

Airway nerve blocks are preferable to lignocaine nebulization as they provide superior-quality airway anesthesia. However, nebulization may be a suitable alternative when a nerve block is not feasible.

Lack of efficacy of pre bronchoscopy inhaled salbutamol on symptoms and lung functions in patients with pre-existing airway obstruction

BACKGROUND

Fiberoptic bronchoscopy (FOB) may exaggerate symptoms and lung functions in patients with pre-existing airway obstruction. Interventions which can alleviate or minimize this procedure-related bronchospasm, especially in this high-risk group are, therefore, required.

METHODS

A double-blinded randomized controlled trial was conducted to evaluate the efficacy of 400 μg of inhaled salbutamol on patients with spirometric evidence of airflow obstruction planned for FOB. Patient's dyspnea, procedure tolerability, and change in spirometry were assessed before and after the procedure.

RESULTS

A total of 50 patients were enrolled (78% males), with a mean (standard deviation) age of 49.8 (6.2) years. There was a significant fall in % predicted FEV1 within each group compared to their respective pre-bronchoscopy values. However, no significant difference in the % predicted or absolute FEV1 level was observed between the two groups. Similarly, although both groups experienced increased dyspnea immediately following FOB, this difference was not significant between the two groups either on the Borg or visual analog scale scales. Pre-FOB anxiety levels and the tolerability of the procedure as assessed by the bronchoscopist were similar in both groups.

CONCLUSION

FOB in patients with pre-existing airway obstruction aggravates cough and dyspnea, with a concomitant decline in FEV1 and FVC. The administration of pre-FOB inhaled salbutamol does not have any significant beneficial effect on procedure-related outcomes.

A Randomized Trial of 1% vs 2% Lignocaine by the Spray-as-You-Go Technique for Topical Anesthesia During Flexible Bronchoscopy

BACKGROUND

The optimal concentration of lignocaine to be used during flexible bronchoscopy (FB) remains unknown. This randomized controlled trial compared the efficacy and safety of 1% and 2% lignocaine solution for topical anesthesia during FB.

METHODS

Consecutive patients were randomized to receive either 1% or 2% lignocaine solution through the bronchoscope by the "spray-as-you-go" technique. The primary outcome of the study was the assessment of cough by the operator and the patient using the visual analog scale (VAS) and pain assessment using the faces pain rating scale. The secondary outcomes included total lignocaine dose, oxygenation status, adverse reactions related to lignocaine, and others.

RESULTS

Five hundred patients were randomized (median age, 51 years; 71% men) 1:1 to either group. The median operator VAS score for cough was significantly higher (25 vs 21, P = .015) in the 1% group; however, the patient VAS score was not significantly different (32 vs 27, P = .065). The pain rating was similar between the two groups. The median cumulative dose of lignocaine was significantly higher in the 2% group (397 mg vs 312 mg, P = .0001; 7.1 mg/kg vs 5.7 mg/kg, P = .0001). About 28% of patients in the 2% group exceeded the maximum recommended dose (> 8.2 mg/kg) of lignocaine. No adverse event related to lignocaine overdose was seen in either group.

CONCLUSIONS

One percent lignocaine was found to be as effective as 2% solution for topical anesthesia during FB, albeit at a significantly lower dose as the latter. Thus, 1% lignocaine should be the preferred concentration for topical anesthesia during FB.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01955824; URL: www.clinicaltrials.gov.

Posterior lingual lidocaine: A novel method to improve tolerance in upper gastrointestinal endoscopy

AIM: To evaluate the effect of posterior lingual lidocaine swab on patient tolerance to esophagogastroduodenoscopy, the ease of performance of the procedure, and to determine if such use will reduce the need for intravenous sedation.

METHODS: Eighty patients undergoing diagnostic esophagogastroduodenoscopy in a tertiary care medical center were randomized to either lidocaine swab or spray. Intravenous meperidine and midazolam were given as needed during the procedure.

RESULTS: Patients in the lidocaine swab group (SWG) tolerated the procedure better than those in the spray group (SPG) with a median tolerability score of 2 (1, 4) compared to 4 (2, 5) (P < 0.01). The endoscopists encountered less difficulty performing the procedures in the SWG with lower median difficulty scores of 1 (1, 5) compared to 4 (1, 5) in the SPG (P < 0.01). In addition, the need for intravenous sedation was also lower in the SWG compared to the SPG with fewer patients requiring intravenous sedation (13/40 patients vs 38/40 patients, respectively, P < 0.01). The patients in the SWG were more satisfied with the mode of local anesthesia they received as compared to the SPG. In addition, the endoscopists were happier with the use of lidocaine swab.

CONCLUSION: The use of a posterior lingual lidocaine swab in esophagogastroduodenoscopy improves patient comfort and tolerance and endoscopist satisfaction and decreases the need for intravenous sedation.

Topical lidocaine through the bronchoscope reduces cough rate during bronchoscopy

BACKGROUND AND OBJECTIVE

Topical lidocaine is often administered through the flexible bronchoscope in an attempt to reduce excessive coughing and patient discomfort. With the increasing use of sedation, including opiates that possess central cough suppressant effects, and the potential for serious clinical toxicity, the need for evidence regarding the efficacy of topical lidocaine is important. This study assessed whether topical lidocaine through the bronchoscope could reduce cough and stridor rate.

METHODS

A randomized controlled trial of 49 patients undergoing flexible bronchoscopy was conducted. Following sedation and topical anaesthesia to the upper airway, patients were randomized to receive either lidocaine 2% or placebo (N-saline) through the bronchoscope to the vocal cords and tracheobronchial tree. Cough and stridor rates were recorded by audiotape. Bronchoscopists and nurses assessed coughing with visual analogue scales.

RESULTS

There were no significant differences in baseline demographics and level of sedation between the two groups. The cough rate per minute (mean (SD)) was lower (P < 0.001) in the lidocaine group, 12.20 (7.99), n = 18, than in the placebo group, 27.50 (10.74), n = 31. The stridor rate was lower with lidocaine, 0.22 (0.60) per minute than with placebo 0.80 (1.35), but the difference was non-significant at P = 0.095. Both doctors' and nurses' scores for cough were significantly lower in the lidocaine group (P < 0.001 for both). Less midazolam 2.1 mg (1.1) was used with lidocaine than with placebo 3.4 mg (1.9), P = 0.02 and less fentanyl 81.9 mg (34.1) versus 98.4 mg (20.4), P = 0.04.

CONCLUSIONS

Topical lidocaine through the bronchoscope significantly decreased cough frequency and the total dose of sedation required during flexible bronchoscopy.

Does nebulized lidocaine reduce the pain and distress of nasogastric tube insertion in young children? A randomized, double-blind, placebo-controlled trial

OBJECTIVES

Nasogastric tube insertion is a common procedure in children that is very painful and distressing. Although nebulized lidocaine has been shown to be effective in reducing the pain and discomfort of nasogastric tube insertion in adults, there have been no similar studies in children. We set out to investigate the role of nebulized lidocaine in reducing pain and distress of nasogastric tube insertion in young children.

METHODS

We conducted a randomized, double-blind, placebo-controlled trial of nebulized 2% lidocaine at 4 mg/kg versus saline placebo during nasogastric tube insertion at a tertiary urban pediatric emergency department. Patients were eligible if they were aged from 1 to 5 years with no comorbid disease and a clinical indication for a nasogastric tube. Nebulization occurred for 5 minutes, 5 minutes before nasogastric tube insertion. Video recordings before, during, and after the procedure were rated using the Face, Legs, Activity, Cry, and Consolability (FLACC) pain and distress assessment tool (primary outcome measure) and pain and distress visual analog scale scores (secondary outcome measures). Difficulty of insertion and adverse events were also assessed.

RESULTS

Eighteen participants were nebulized with 2% lidocaine and 18 participants with normal saline. Nebulization was found to be highly distressing. FLACC scores during nasogastric tube insertion were very high in both groups. There was a trend in the post-nasogastric tube insertion period toward lower FLACC scores in the lidocaine group. Visual analog scale scores for this postinsertion period were significantly lower in the lidocaine arm for pain and distress. There were no significant differences between groups in terms of difficulty of insertion and the number of minor adverse events. The study was terminated early because of the distress and treatment delay associated with nebulization.

CONCLUSIONS

Nasogastric tube insertion results in very high FLACC scores irrespective of lidocaine use. Nebulized lidocaine cannot be recommended as pain relief for nasogastric tube insertion in children. The delay and distress of nebulization likely outweigh a possible benefit in the postinsertion period.

[Diagnostic flexible bronchoscopy. Recommendations of the Endoscopy Working Group of the French Society of Pulmonary Medicine]

These guidelines on flexible bronchoscopy depict important clues to be known and taken into account while practicing flexible bronchoscopy, in adult, except in emergency situations. This is a practical clarification. Safety conditions, complications, anesthesia, infectious risks, cleaning and disinfection are detailed from a review of the literature. Intensive care practice of bronchoscopy requires more attention due to higher risks patients and is discussed extensively. Standards and performances of the various sampling techniques complete this work. Indications for bronchoscopy, therapeutic and paediatric bronchoscopy are not covered in these guidelines.

[Plasma concentration of lidocaine during bronchoscopy]

Lidocaine is commonly used for local anesthesia during fiberoptic bronchoscopy (FOB). It has been suggested that the total dose of lidocaine should be limited to 300-400 mg (or < 8.2 mg/kg). Lidocaine toxicity is directly correlated with its concentration in the blood and a threshold above which the side effects become more likely has been put at a plasma level of 5 microg/ml. The aim of our study was to determine plasmatic lidocaine concentrations (PLC), how often the PLC fall into the potentially toxic range and its correlation with adverse reactions. PLC were recorded in 30 patients undergoing FOB. Lidocaine was administered as a 2% gel, 10% spray and 2% solution. Venous blood samples were taken before the beginning of local anesthesia and at 20, 30 and 40 min thereafter. The mean total amount of lidocaine administered was 746.3 +/- 159.5 mg (11.6 +/- 3.1 mg/kg). Before the beginning of anesthesia, no significant levels of lidocaine were measurable in the patients. PLC were 3.2 +/- 1.7 (g/ml at 20 min., 3.3 +/- 1.7 microg/ml at 30 min. and 3.0 +/- 1.5 microg/ml at 40 min. The PLC exceeded toxic levels in 6 patients, but no complications were observed. Our data show that although the amount of lidocaine used in this study exceeded the recommended highest dose, no subjects had signs of toxicity. A maximum dose of lidocaine for topical anesthesia should be determined despite the fact that an average total dose superior to 400 mg appears to be safe in patients undergoing FOB.

Fibre-optic bronchoscopy in adults: a position paper of The Thoracic Society of Australia and New Zealand

Fibre-optic bronchoscopy in adults is a common procedure in clinical respiratory practice. Under controlled conditions it is safe, resulting in relatively few significant adverse events. The present position paper updates guidelines previously published by The Thoracic Society of Australia and New Zealand and is based on evidence obtained by searching the Medline and Embase databases. The level of evidence to support recommendations is indicated in the text. Where no evidence has been found, the guidelines reflect the opinions of the authors. Specific recommendations are made regarding sedation and anaesthesia, the cleaning of bronchoscopes and the training of bronchoscopists.

The effects of intracuff lidocaine on endotracheal-tube-induced emergence phenomena after general anesthesia

Coughing during emergence from general anesthesia is a common clinical problem. We sought to determine whether inflating the endotracheal tube cuff with lidocaine would create a reservoir of local anesthetic, which might diffuse across the cuff membrane to anesthetize the mucosa, thus attenuating stimulation during extubation of the trachea. A total of 63 patients undergoing elective surgery were enrolled in a prospective, randomized, double-blinded study. After intubation of the trachea with an endotracheal tube, the cuff of the tube was inflated with either lidocaine 4%, saline, or air. After extubation, a blinded observer noted heart rate, blood pressure, oxygen saturation, end-tidal isoflurane concentration, and the incidence of coughing. Data were analyzed by using analysis of variance, Student's t-test, and the chi(2) test for multiple variables. The groups were demographically comparable. There was no difference in hemodynamic or oxygen saturation data between either group. The incidence of coughing was decreased in the lidocaine group for the time period of 4-8 min postextubation (P < 0.05). We conclude that inflation of the cuff of the endotracheal tube can reduce the incidence of coughing in the initial postextubation period, a finding that may benefit certain patient groups in which this is particularly desirable.

IMPLICATIONS

Tracheal intubation with an endotracheal tube is often necessary during anesthesia. After intubation, inflating a cuff around the endotracheal tube maintains a seal. This can result in coughing during emergence from anesthesia. Our study shows that inflating the cuff of an endotracheal tube with lidocaine rather than air can reduce the incidence of postextubation coughing.

Serum lidocaine concentrations in asthmatics undergoing research bronchoscopy

STUDY OBJECTIVES

To determine how often serum lidocaine concentrations (SLC) fall into the potentially toxic range (> 5 mg/L) in asthmatics undergoing research bronchoscopy, and to determine whether subject or procedure characteristics are associated with higher SLC.

DESIGN

Prospective, observational study.

SETTING

Academic research center.

PARTICIPANTS

Fifty-one volunteers with mild to moderate asthma enrolled in three separate bronchoscopy protocols to study airway inflammation in asthma.

INTERVENTIONS

Lidocaine was administered topically to the upper airway and tracheobronchial tree to achieve local anesthesia for bronchoscopy. Venous blood was sampled during bronchoscopy, 30 min after upper airway anesthesia was completed (time 1), and 30 min after bronchoscopy was completed (time 2).

MEASUREMENTS AND RESULTS

The mean total amount of lidocaine administered was 600 +/- 122 mg (8.2 +/- 2.0 mg/kg). No signs or symptoms of lidocaine toxicity were observed in any of the subjects. SLC ranged between 0.10 and 2.90 mg/L at time 1 and 0.50 and 3.20 mg/L at time 2. SLC was significantly correlated with the total amount of lidocaine (milligrams/kilogram) administered at both points (time 1, r = 0.33, p = 0.021; time 2, r = 0.33, p = 0.023). No statistically significant relationship was observed between SLC and subject age, sex, weight, baseline FEV(1), procedure length, or study protocol. No statistically significant relationship was found between subject FEV(1) and either total lidocaine dose or procedure length.

CONCLUSIONS

An average total dose of 600 mg (8.2 mg/kg) of lidocaine appears to be safe in mild to moderate asthmatics undergoing research bronchoscopy.

An assessment of prilocaine as a topical anaesthetic agent for fibreoptic bronchoscopy in comparison with lidocaine

We have evaluated prilocaine as a topical anaesthetic agent for fibreoptic bronchoscopy in comparison with lidocaine in terms of efficacy and safety. Forty patients were included in a randomised double-blind parallel-group study. Efficacy was assessed using visual analogue scales, a patient ranking scale and the number of doses of local anaesthetic and intravenous sedative required. Measures of toxicity included peak plasma concentration of local anaesthetic, whether supplementary oxygen was needed and change in methaemoglobin concentration. For most of the outcome variables, the medians and quartiles were similar for the two local anaesthetics. However, the median peak plasma concentration of prilocaine (0.5 micrograms.ml-1) was less than one-third that of lidocaine (1.76 micrograms.ml-1). The merits and hazards of using multiple-regression modelling to improve the precision of the analysis of the results are considered. We conclude that prilocaine can be used successfully as a topical anaesthetic agent for fibreoptic bronchoscopy and is associated with a lower risk of toxicity.

Systemic absorption of topical lidocaine in elderly and young adults undergoing bronchoscopy

This study compared the systemic absorption of topically administered lidocaine in elderly and young adult patients who were undergoing fiberoptic bronchoscopy. Fourteen elderly subjects aged 60-72 years (mean 67 years) and five young subjects age 31-48 years (mean 42 years) were compared with respect to dosage requirements to achieve satisfactory local anesthesia, rate and extent of lidocaine systemic absorption, plasma drug levels, elimination half-life, and drug side effects. Blood samples were drawn prior to, during, and for an average of 3 hours after the completion of bronchoscopy. Lidocaine plasma concentrations averaged in the range of 3.04-0.88 micrograms/ml from the beginning of the procedure to the end of blood sampling. Despite high cumulative amounts of 19 mg/kg (1200 mg) of lidocaine administered topically, the regimen proved relatively safe and achieved satisfactory anesthesia. In patients without known risk factors either for delayed hepatic lidocaine clearance or for enhanced mucosal absorption, the regimen is suitable for both young and old individuals.