Serum concentrations of lignocaine and its metabolite monoethylglycinexylidide during fibre-optic bronchoscopy in local anaesthesia

Is Additional Nebulized Lidocaine Helpful in Flexible Bronchoscopy?: A Meta-Analysis

BACKGROUND

Conflicting evidence of nebulized lidocaine use in bronchoscopy still exist. This study will identify whether there is any difference in various patient-related, physician-related, or procedure-related outcomes with and without lidocaine nebulization before the procedure.

METHOD

The authors performed a search in 4 electronic databases, including Pubmed, Scopus, Virtual Health Library, and Google Scholar from inception to August 2019. Data on patient-reported and physician-reported outcomes, doses of sedation, and lidocaine were extracted and pooled into standardized mean difference (SMD) and mean difference (MD) using the random-effect model.

RESULTS

Seven randomized controlled trials with 1366 patients were included. Cough was not different between the nebulized lidocaine group and no nebulized lidocaine group (SMD, -0.12; 95% confidence interval, -0.82 to 0.59; I, 95%; P=0.75), so as operator's satisfaction score, ease of the procedure, patient's discomfort, and unwillingness to repeat the procedure. Additional nebulized lidocaine group required higher lidocaine dose (MD, 81.93; 95% confidence interval, 17.14-146.71). Studies using only local anesthesia favored the "no additional lidocaine" group in improving cough, operator's satisfaction score, and ease of the procedure. Subgroup analysis of studies using moderate sedation showed a decrease in midazolam dose and duration of the procedure in the "additional nebulized lidocaine group."

CONCLUSION

Additional administration of nebulized lidocaine increased the total dose of lidocaine used and did not improve cough symptoms, operator-satisfaction score, ease of the procedure, and willingness to repeat the procedure. Subgroup analysis of studies using moderate sedation showed a decrease in midazolam use and in procedure duration but the clinical significance of these findings is uncertain.

In situ sprayed NIR-responsive, analgesic black phosphorus-based gel for diabetic ulcer treatment

The treatment of diabetic ulcer (DU) remains a major clinical challenge due to the complex wound-healing milieu that features chronic wounds, impaired angiogenesis, persistent pain, bacterial infection, and exacerbated inflammation. A strategy that effectively targets all these issues has proven elusive. Herein, we use a smart black phosphorus (BP)-based gel with the characteristics of rapid formation and near-infrared light (NIR) responsiveness to address these problems. The in situ sprayed BP-based gel could act as 1) a temporary, biomimetic "skin" to temporarily shield the tissue from the external environment and accelerate chronic wound healing by promoting the proliferation of endothelial cells, vascularization, and angiogenesis and 2) a drug "reservoir" to store therapeutic BP and pain-relieving lidocaine hydrochloride (Lid). Within several minutes of NIR laser irradiation, the BP-based gel generates local heat to accelerate microcirculatory blood flow, mediate the release of loaded Lid for "on-demand" pain relief, eliminate bacteria, and reduce inflammation. Therefore, our study not only introduces a concept of in situ sprayed, NIR-responsive pain relief gel targeting the challenging wound-healing milieu in diabetes but also provides a proof-of-concept application of BP-based materials in DU treatment.

Local anaesthetic toxicity during an awake tracheal intubation course

We report a case of local anaesthetic toxicity in an anaesthetic trainee participating as a subject for an awake tracheal intubation training course. The trainee experienced symptoms of toxicity despite the dose of lidocaine administered being less than the maximum safe dose recommended for airway topicalisation. We argue this highlights the variability in absorption of local anaesthetic and the importance of safety during awake tracheal intubation training courses. It is essential to use the minimum safe dose of local anaesthetic required during topicalisation for awake tracheal intubation. We have now made it our course policy that participants cannot undergo awake tracheal intubation less than 2 weeks before a period of coryzal illness. We recommend that operators remain vigilant for signs of local anaesthetic toxicity when undertaking this procedure and adhere to newly published Difficult Airway Society awake tracheal intubation guidelines.

Difficult Airway Society guidelines for awake tracheal intubation (ATI) in adults

Awake tracheal intubation has a high success rate and a favourable safety profile but is underused in cases of anticipated difficult airway management. These guidelines are a comprehensive document to support decision making, preparation and practical performance of awake tracheal intubation. We performed a systematic review of the literature seeking all of the available evidence for each element of awake tracheal intubation in order to make recommendations. In the absence of high‐quality evidence, expert consensus and a Delphi study were used to formulate recommendations. We highlight key areas of awake tracheal intubation in which specific recommendations were made, which included: indications; procedural setup; checklists; oxygenation; airway topicalisation; sedation; verification of tracheal tube position; complications; management of unsuccessful awake tracheal intubation; post‐tracheal intubation management; consent; and training. We recognise that there are a range of techniques and regimens that may be effective and one such example technique is included. Breaking down the key practical elements of awake tracheal intubation into sedation, topicalisation, oxygenation and performance might help practitioners to plan, perform and address complications. These guidelines aim to support clinical practice and help lower the threshold for performing awake tracheal intubation when indicated.

Guidelines for diagnostic flexible bronchoscopy in adults: Joint Indian Chest Society/National College of chest physicians (I)/Indian association for bronchology recommendations

Flexible bronchoscopy (FB) is commonly performed by respiratory physicians for diagnostic as well as therapeutic purposes. However, bronchoscopy practices vary widely across India and worldwide. The three major respiratory organizations of the country supported a national-level expert group that formulated a comprehensive guideline document for FB based on a detailed appraisal of available evidence. These guidelines are an attempt to provide the bronchoscopist with the most scientifically sound as well as practical approach of bronchoscopy. It involved framing appropriate questions, review and critical appraisal of the relevant literature and reaching a recommendation by the expert groups. The guidelines cover major areas in basic bronchoscopy including (but not limited to), indications for procedure, patient preparation, various sampling procedures, bronchoscopy in the ICU setting, equipment care, and training issues. The target audience is respiratory physicians working in India and well as other parts of the world. It is hoped that this document would serve as a complete reference guide for all pulmonary physicians performing or desiring to learn the technique of flexible bronchoscopy.

Nebulized lignocaine for topical anaesthesia in no-sedation bronchoscopy (NEBULA): A randomized, double blind, placebo-controlled trial

Background:

The role of nebulized lignocaine administration for flexible bronchoscopy is unclear.

Methods:

In this randomized, double-blind, placebo-controlled trial, subjects undergoing diagnostic flexible bronchoscopy were randomized to receive either nebulized lignocaine (2.5 ml of 4% lignocaine) or nebulized (2.5 ml of 0.9%) saline (placebo). All received 10% lignocaine pharyngeal spray (4 sprays) and 5-ml nasal 2% lignocaine gel. 1% lignocaine solution was used for spray-as-you-go administration in all. Co-primary outcomes were Operator-rated overall procedure satisfaction and Operator-rated cough scores on Visual Analog Scale (VAS). Secondary objectives were cumulative lignocaine dose, proportion of subjects receiving >8.2-mg/kg lignocaine, and complications between the groups.

Results:

Two hundred and twenty subjects were randomized and 217 (109 – nebulized lignocaine and 108 – placebo) received the intervention. Baseline characteristics were comparable. Operator-rated overall procedure satisfaction scores on VAS (7.30 ± 1.54 nebulized lignocaine and 7.50 ± 1.31 placebo group, P = 0.85) and Operator-rated cough scores on VAS (3 [2–5] nebulized lignocaine and 3 [2–4] placebo group, P = 0.18) were similar. Cumulative lignocaine dose was significantly greater in nebulized lignocaine group (331.46 ± 9.41 mg vs. 232.22 ± 12.77 mg, P < 0.001), and a significantly greater number of subjects in this group received lignocaine dose >8.2 mg/kg. Minor complications occurred in 6 and 9 subjects in nebulized lignocaine and placebo groups, respectively, P = 0.41.

Conclusion:

Administration of nebulized lignocaine in addition to pharyngeal lignocaine spray, during no-sedation bronchoscopy, increases the cumulative lignocaine dose without improved procedural comfort. Additional nebulized lignocaine during bronchoscopy is not recommended.

A randomized double-blind controlled trial comparing three sedation regimens during flexible bronchoscopy: Dexmedetomidine, alfentanil and lidocaine

INTRODUCTION

No standardized sedation protocol is available for flexible bronchoscopy (FB).

OBJECTIVES

The aim of this study was to evaluate the efficacy and safety of three regimens used for sedation during FB.

METHODS

This randomized double-blind controlled trial assessed patients undergoing bronchoscopy and receiving lidocaine alone (C) or combined with dexmedetomidine (D) or alfentanil (A). Tolerance was assessed using the bronchoscopy score, and level of sedation was assessed using the Nursing Instrument for the Communication of Sedation. Safety was evaluated in terms of pulmonary function and vital signs.

RESULTS

A total of 162 patients were enrolled. The bronchoscopy score was identical in all groups. Group D subjects were the most sedated (P = .013), whereas group A subjects were the least agitated. Linear regression showed a negative association between bronchoscopy score and age in A (β = -0.06; P = .001). Positive predictors of bronchoscopy score were female gender (β = 1.96; P = .003) in D and obesity (β = 2.41; P = .012), longer procedures (β = 0.08; P = .009) and female gender (β = 1.15; P = .038) in C. Longer procedures (β = -0.12; P = .010) was a negative predictor of bronchoscopy score in D. Desaturation, hypoxia and heart rate changes were most prevalent in group A. Hypotension was mostly observed in D.

CONCLUSIONS

No consistent differences were present between the three regimens; however, each was more appropriate in certain patient profiles. We consequently proposed a protocol as a first step towards standardizing sedation practice in FB in a patient-tailored manner. A more comprehensive and detailed protocol including other sedative agents with their corresponding doses should be developed.

Lignocaine topicalization of the pediatric airway

The application of topical laryngeal lignocaine is a technique used frequently in pediatric anesthesia. It is often used to facilitate open airway procedures, tracheal intubation, or to reduce the incidence of perioperative adverse respiratory events such as coughing and laryngospasm. A number of studies have shown that applying topical lignocaine to the larynx reduces perioperative respiratory adverse events, while others have shown an increased incidence of respiratory complications with lignocaine administration. There is a lack of evidence on the effect of topical lignocaine on the sensitivity of upper airway reflexes and swallowing, the duration of time that airway reflexes are obtunded, and the optimum and safe maximum dose of lignocaine when used by this route. We review the current literature relating to the use of lignocaine to topicalize the pediatric airway. This review concentrates on the indications for use, the maximum safe dose, the effect on swallowing, and risk of aspiration and the complications of the technique.

[Delayed convulsion after lidocaine instillation for bronchoscopy]

INTRODUCTION

Lidocaine toxicity usually appears rapidly and is directly correlated with plasma concentrations of the drug.

CASE REPORT

We report a case of a late neurologic toxicity occurring after instillation of lidocaine during fibre-optic bronchoscopy. A patient with bronchiolitis obliterans underwent a diagnostic bronchoscopy. She received multiples instillations of Xylocaine(®) 2% (lidocaine). Three and a half hours later, she had a tonic-clonic seizure. Seven hours later, this recurred. Lidocaine plasma levels were in the toxic range at the time of the first seizure (18.32μg/mL) with a significant decrease in the concentration noted 24hours later.

CONCLUSION

The slow absorption of lidocaine into the blood from the bronchial tree explains the delayed neurologic toxicity. Our observation is a reminder that complications can occur due to high doses of lidocaïne administrated by instillation. Thus, if the recommended dose of lidocaine is exceeded, it is essential to monitor patients closely for a prolonged period, especially those with fibrosing lung disease in order to avoid possible late toxicity.

Life-threatening anaphylactic reaction after the administration of airway topical lidocaine

A 9-year-old boy who developed a life-threatening anaphylaxis reaction of the airway and subsequent dyspnea and circulation collapse because of instilled the topical lidocaine into the airway within 2 min before performing flexible bronchoscopy (FB). FB revealed swollen airway mucosa and extensive foamy secretion that severely compromised the ventilation lumen. Rapid detection with FB and immediate resuscitation, including prompt administration of epinephrine, volume expander, and positive pressure ventilation with pure oxygen via an endotracheal tube, were successfully save the patient's life.

Atomised lidocaine for airway topical anaesthesia in the morbidly obese: 1% compared with 2%

Airway anaesthesia using atomised lidocaine for awake oral fibreoptic intubation in morbidly obese patients was evaluated using two doses of local anaesthetic. In this randomised, blinded prospective study, 40 ml of atomised 1% (n = 11) or 2% (n = 10) lidocaine was administered with high oxygen flow as carrier. Outcomes included time for intubation, patient tolerance to airway manipulation, haemodynamic parameters, the bronchoscopist's overall satisfaction, and serial serum lidocaine concentrations. Patients receiving lidocaine 1% had a longer mean (SD) time from the start of topicalisation to tracheal tube cuff inflation than those receiving lidocaine 2% (8.6 (0.9) min vs 6.9 (0.5) min, respectively; p < 0.05). Patients in the 1% cohort demonstrated increased responses to airway manipulation (p < 0.0001), reflecting lower bronchoscopist's satisfaction scores (p < 0.03). Haemodynamic responses to topicalisation and airway manipulation were similar in both groups. Peak plasma concentration was lower in the 1% group (mean (SD) 1.4 (0.3) and 3.8 (0.5) microg.ml(-1), respectively; p < 0.001). Airway anaesthesia using atomised lidocaine for awake oral fibreoptic intubation in the morbidly obese is efficacious, rapid and safe. Compared with lidocaine 1%, the 2% dose provides superior intubating conditions.

Spray-as-you-go airway topical anesthesia in patients with a difficult airway: a randomized, double-blind comparison of 2% and 4% lidocaine

BACKGROUND

We designed this randomized, double-blind clinical study to compare the safety and efficacy of 2% and 4% lidocaine during airway topical anesthesia with a spray-as-you-go technique via the fiberoptic bronchoscope.

METHODS

Fifty-two adult patients with a difficult airway were randomly assigned to 1 of 2 study groups to receive 2% (Group 1) or 4% lidocaine (Group 2) by a spray-as-you-go technique with the fiberoptic bronchoscope, in a double-blind manner. After airway topical anesthesia, awake fiberoptic orotracheal intubation (FOI) was performed. Level of sedation, time for each lidocaine spray in different targeted areas, total times for airway sprays, total dosages of lidocaine used for airway sprays, intubation times, and number of intubation attempts were noted. An independent investigator scored patients' comfort during airway topical anesthesia, patients' reaction, coughing severity, and intubating condition during awake FOI, and observed changes of arterial blood pressure and heart rate during each stage in the airway manipulation process. Serial blood samples were obtained for analysis of plasma lidocaine concentrations.

RESULTS

Except for the total dosages and plasma concentrations of lidocaine, there were no significant differences in any of the observed variables between groups. All patients exhibited excellent or acceptable intubating conditions. The total dosages of lidocaine were significantly smaller in Group 1 (3.4 +/- 0.6 mg/kg) than in Group 2 (7.1 +/- 2.1 mg/kg). The plasma lidocaine concentrations in all observed points after the supraglottic sprays were larger in Group 2 than in Group 1.

CONCLUSIONS

Both 2% and 4% lidocaine administered topically by a spray-as-you-go technique can provide clinically acceptable intubating conditions for awake FOI in sedated patients with a difficult airway. As compared with 4% lidocaine, however, 2% lidocaine requires a smaller dosage and results in lower plasma concentrations.

[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.

Broncoscopia flexible en el niño: indicaciones y aspectos generales

There is considerable interhospital variability in the practice of flexible bronchoscopy in children. The present report aims to provide some recommendations that are supported by the Spanish Society of Pediatric Pulmonologists. We review the indications, contraindications, equipment, setting and personnel involved in flexible bronchoscopy, as well as the pre-procedure preparation of the patient, medications, post-procedure monitoring, complications, care and maintenance of instruments, and informed consent. These recommendations may be adopted, modified or rejected according to clinical needs and constraints.

Sedation in outpatient bronchoscopy

Bronchoscopy is a procedure that is likely to provoke anxiety as the patient is surrounded by monitoring and bronchoscopy equipment, and care is administered by strangers who perform intimate, invasive, and sometimes, painful procedures. Sedation is needed, therefore, to allay anxiety and reduce stress, improve patient comfort and co-operation, provide amnesia and facilitate the bronchoscopic procedure. In this review we try to summarize the current knowledge on currently used sedation protocols with special reference to the commonly used pharmacological agents. We believe sedation should be used routinely in fiberoptic bronchoscopy in order to achieve a safe and pleasant procedure for both the patient and the pulmonologist.

Management of a pregnant patient with airway obstruction secondary to goitre

A case of airway obstruction in advanced pregnancy is presented. The patient was successfully managed with an awake fibreoptic intubation performed orally followed by a caesarean section and thyroidectomy as a combined procedure. On resection, a thyroid gland weighing 370 g was removed. The patient made an uneventful recovery.

Patient satisfaction with conscious sedation for bronchoscopy

STUDY OBJECTIVE

Bronchoscopic technique is not standardized. Controversies exist with regard to premedication with sedatives before the test. To evaluate safety and efficacy of conscious sedation, we studied 100 randomized patients undergoing diagnostic bronchoscopy; patients received premedication with lidocaine spray and atropine sulfate i.m. (nonsedation group; 50 patients) or lidocaine spray, atropine i.m. and diazepam i.v. (sedation group; 50 patients).

METHODS AND RESULTS

Monitoring during flexible fiberoptic bronchoscopy included continuous ECG and pulse oximetry. The procedure could not be completed in six patients. None received premedication with diazepam; among the patients who ended the examination, tolerance to the examination (visual analogue scale, 0 to 100; 0 = excellent; 100 = unbearable) was better in the sedation group. Low anxiety, male sex, but not age were also associated with improved patient tolerance to the test. Oxygen desaturation occurred in 17% of patients, and it was not more frequent after diazepam treatment.

CONCLUSIONS

In our study, sedation had a beneficial effect on patient tolerance and rarely induced significant alterations in cardiorespiratory monitoring parameters.