Effectiveness and safety of endotracheal tube cuffs filled with air versus filled with alkalinized lidocaine: a randomized clinical trial

Effectiveness of intracuff alkalinized lidocaine associated with intravenous dexamethasone in reducing laryngotracheal morbidity in children undergoing general anesthesia for tonsillectomy: a randomized controlled trial

BACKGROUND

Postoperative sore throat is one of the main postoperative complaints in patients undergoing tonsillectomy. As the primary outcome, we aimed to determine whether endotracheal tube cuffs filled with alkalinized lidocaine are associated with a lower incidence of postoperative sore throat and anesthesia emergence phenomena in children undergoing tonsillectomy or adenotonsillectomy. We also assessed the potential additional benefits of IV dexamethasone in reducing postoperative laryngotracheal morbidity.

METHODS

This is a clinical prospective, randomized, controlled trial. Patients were randomly allocated to one of four groups, as follows: air - endotracheal tube cuff filled with air; air/dex - endotracheal tube cuff filled with air and intravenous dexamethasone; lido - endotracheal tube cuff filled with alkalinized lidocaine; and lido/dex - endotracheal tube cuff filled with alkalinized lidocaine and intravenous dexamethasone. Perioperative hemodynamic parameters and the incidence of postoperative nausea and vomiting, coughing and hoarseness were recorded. Postoperative sore throat was assessed in the postanesthetic care unit and 24 hours post tracheal extubation.

RESULTS

In total, 154 children aged 4-12 years, ASA physical status I or II, undergoing general anesthesia for elective tonsillectomy and adenotonsillectomy, were assessed for postoperative sore throat in this study. The incidence of postoperative sore throat 24 hours after tracheal extubation was significantly lower in the lido/dex group compared to groups air and air/dex (p = 0.01). However, no additional reduction in these symptoms was observed from the intravenous administration of dexamethasone when comparing the lido and lido/dex groups. Similarly, there were no differences among groups regarding perioperative hemodynamic variables or postoperative nausea and vomiting, coughing, and hoarseness during the study period.

CONCLUSION

Intracuff alkalinized lidocaine, associated with intravenous dexamethasone, might be effective in reducing sore throat 24 hours post-tonsillectomy or adenotonsillectomy in children when compared to the use of air as the cuff insufflation media.

Intracuff Lidocaine and Postoperative Throat Mucosal Injuries: An Evidence-based Review

PURPOSE

Examine the effectiveness of using intracuff lidocaine to minimize postoperative complications.

DESIGN

Systematic review.

METHODS

This review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Guidelines. PubMed, CINAHL, Cochrane, Google Scholar, and gray literature databases were searched to obtain eligible studies and minimize selection bias. The Johns Hopkins Nursing Evidence-Based Practice Model was used to appraise the level of evidence for the varying studies. Only randomized controlled trials (RCT) and systematic reviews with meta-analyses of RCTs were included in the review.

FINDINGS

Three RCTs and three systematic reviews with meta-analyses incorporating a total of 2,337 patients were included in this review. Intracuff lidocaine (alkalinized and nonalkalinized) had the lowest incidence of postoperative sore throat in the early and late postoperative periods compared to intracuff air or intracuff saline. Furthermore, the evidence suggested that the use of intracuff lidocaine reduced postextubation cough and the incidence of hoarseness but had little or no effect on dysphagia. All studies were Level 1 and Grade A, indicating clinically solid evidence in analyzing intracuff lidocaine's effect on all outcomes measured.

CONCLUSIONS

The current literature suggests the feasibility of using intracuff lidocaine as an effective method to reduce the incidence of postoperative sore throat, postextubation cough, and hoarseness. The implications to practice include improving the norm of postoperative throat mucosal injuries by implementing an evidence-based practice intervention of intracuff lidocaine.

Lidocaine aerosol preoperative application for improving the comfort of pediatric patients undergoing tonsillectomy and adenoidectomy: A prospective randomized controlled trial

Background and Aims

The use of lidocaine aerosol for pediatric tonsil and adenoidectomy has been reported less frequently. We hope to improve the perioperative comfort of pediatric patients undergoing these procedures by applying lidocaine aerosol.

Methods

A total of 122 pediatric patients receiving tonsil and adenoidectomy were randomly divided into a lidocaine aerosol group (Group L) and a saline group (Group C), with 61 patients in each group; 2.4% alkaline lidocaine aerosol and saline were sprayed in the pharynx before induction. Our primary outcome were the incidence and rate ratio (RR) of postoperative pharyngeal complications (oropharyngeal dryness, dysphagia, hoarseness, and sore throat) and the pharyngeal comfort score, the latter of which was assessed by the occurrence of the above complications (yes = 0 point, none = 1 point). The secondary outcomes included preoperative and intraoperative blood pressure and heart rate, the incidence of choking during the induction period, the intraoperative opioid dosage, and the pain level and depth of sedation at 2, 6, and 24 h postoperatively. Statistical software used in this study included PASS15.0, SPSS 26.0, and GraphPad Prism 9.3.1, and statistical methods used included the t-test, the χ² test, the Mann-Whitney U test, and the repeated measures analysis of variance.

Results

The incidence and RR of postoperative pharyngeal complications such as oropharyngeal dryness (RR: 0.667, 95% confidence interval [CI]: 0.458-0.970, p = 0.03), dysphagia (RR: 0.333, 95% CI: 0.114-0.976, p = 0.03), hoarseness (RR: 0.647, 95% CI: 0.433-0.967, p = 0.03), and sore throat (RR: 0.727, 95% CI: 0.547-0.967, p = 0.03) were significantly lower in Group L than in Group C at 2 h postoperatively, and the incidence and RR of postoperative sore throat was significantly lower in Group L than in Group C at 6 h postoperatively (RR: 0.717, 95% CI: 0.547-0.942, p = 0.01). The postoperative pharyngeal comfort scores were significantly higher in Group L than in Group C at all postoperative time points (p < 0.05). The Ramsay sedation score was significantly higher (p < 0.01) and FLACC (face, legs, activity, crying, and consolability) score was significantly lower (p < 0.01) in Group L than in Group C at 2 h postoperatively. In Group C, the blood pressure and heart rate significantly faster at all time points immediately after intubation and afterward, except at the end of surgery (p < 0.05).

Conclusions

In pediatric tonsil and adenoidectomy, the application of lidocaine aerosol before induction can reduce the incidence of postoperative pharyngeal complications, improve the child's postoperative pharyngeal comfort, and better realize perioperative "comfort medical treatment."

Effect of tracheal tube cuff inflation with alkalinized lidocaine versus air on hemodynamic responses during extubation and post-operative airway morbidities in children: prospective observational cohort study, Ethiopia

Background

Endotracheal tube with an inflated cuff was used to manage and maintain the airway during general anesthesia in children. When the lateral pressure exerted by an inflated Endotracheal tube cuff on tracheal mucosa exceeds capillary perfusion pressure, patients may complain of cough, sore throat, and hoarseness in the postoperative period. This study aimed to assess the effect of a tracheal tube cuff filled with alkalinized lidocaine versus air on hemodynamic parameter changes during extubation and post-operative airway morbidity in children.

Methods

Institutional based observational prospective cohort study was conducted among 56 elective children; aged 3–13 years, who underwent operation under general anesthesia with cuffed endotracheal intubation for greater than one hour by grouping into the air (group1) and alkalinized Lidocaine (group2) at Tikur Anbessa specialized Hospital. Hemodynamic parameters (Heart rate and Blood pressure) and other variables were measured starting from 5 min before extubation to 24th hours after extubation of the endotracheal tube. A Comparison of numerical variables between study group was done with an independent t-test. Data were expressed in terms of mean ± standard deviation. Categorical data were assessed by Chi-square tests.

Results

Postoperative Sore throat was lower in alkalinized lidocaine group compared to the air group. The mean heart rate at five minutes after extubation was significantly lower in alkalinized lidocaine group (107.29 ± 6.457 beat per minute (bpm)) compared to the air group (122.04 ± 8.809 bpm), with P ≤ 0.001. Systolic blood pressure was also significantly lower in alkalinized lidocaine group (99.64 ± 8.434 millimeters of mercury (mmHg)) compared to the air group (108.21 ± 11.902 mmHg), p = 0.016 at five minutes after extubation.

Conclusion

Alkalinized lidocaine inflated tracheal tubes have shown improved hemodynamic and laryngotracheal morbidities in children.

A randomised controlled trial of intracuff lidocaine and alkalised lidocaine for sedation and analgesia requirements in mechanically ventilated patients

Background

Airway irritation caused by prolonged inflation of endotracheal tube (ETT) cuff results in post-intubation morbidities.

Objectives

We aimed to study intracuff lidocaine and alkalised lidocaine on sedation or analgesia requirements of patients undergoing mechanical ventilation in the intensive care unit (ICU). The primary outcome was to calculate the total dose of propofol and fentanyl required to obtund the unwanted airway and circulatory reflexes. Secondary outcomes were to determine the frequency and severity of cough and haemodynamic parameters.

Methods

It was a double-blinded, randomised controlled study in the ICU after emergency laparotomy, in patients aged 20 - 55 years, and classified as American Society of Anesthesiologists (ASA) classes 1E and 2E with tube in situ. Exclusion criteria were patients with body mass index >30 kg/m² , haemodynamic instability, requiring positive end-expiratory pressure ≥7 cm H2O, and a history of chronic obstructive pulmonary disease. After ethics clearance and written consent, patients were randomly assigned into two groups (36 in each), Group L (ETT cuff inflated with lidocaine 2%) and Group AL (cuff inflated with a mixture of lidocaine 2% and sodium bicarbonate 1:1).

Results

Mean dose of propofol consumed in Group AL was significantly less than that in Group L (p<0.001). The mean standard deviation (SD) fentanyl utilisation in Group AL was 1 323.61 (187.27) µg, and that in Group L was 1433.09 (42.58) µg (p=0.040). Group L patients had a significantly higher incidence of cough than those in Group AL (p=0.01). There was no significant difference in the mean arterial pressure (p=0.22), although heart rate was significantly higher in Group L (p<0.001).

Conclusion

Alkalised lidocaine reduces the requirement of sedation, analgesia, and the incidence of cough in intubated patients maintaining haemodynamic stability when compared with lidocaine.

Contributions of the study

Alkalised lidocaine when used in endotracheal tube cuff inflation reduces the need for sedation and analgesia in mechanically-ventilated patients, and improves haemodynamic stability.

Intracuff alkalinized lidocaine to prevent postoperative airway complications: A meta-analysis

BACKGROUND

Post-extubation cough is a common phenomenon in surgical patients undergoing general anesthesia, which can lead to potentially dangerous complications. In this meta-analysis, we evaluated the efficacy and safety of intracuff alkalinized lidocaine in patients with tracheal intubation to prevent cough and other airway complications during the perioperative period.

AIM

To perform a systematic review and meta-analysis of intracuff alkalinized lidocaine for the prevention of postoperative airway complications.

METHODS

PubMed, Embase, Cochrane, and Web of Science were searched for randomized controlled trials (RCTs) that compared intracuff alkalinized lidocaine to placebo. We used risk-of-bias assessment to assess the RCTs, and the quality of evidence was assessed using the grading of recommendations, assessment, development, and evaluations.

RESULTS

Twelve randomized trials (1175 patients) were analyzed. Meta-analysis showed that intracuff alkalinized lidocaine was associated with less cough compared to that produced by placebo [risk ratio (RR): 0.38; 95% confidence interval (CI): 0.23-0.63]. Similarly, intracuff alkalinized lidocaine was more effective than the control in reducing postoperative sore throat at 24 h (RR: 0.19; 95%CI: 0.09-0.41) and postoperative hoarseness (RR: 0.38; 95%CI: 0.21-0.69).

CONCLUSION

Intracuff alkalinized lidocaine is an effective adjuvant that can decrease airway complications, such as coughing, hoarseness, and sore throat.

Respiratory care for the critical patients with 2019 novel coronavirus

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted through respiratory droplets, aerosols and close contact. Cross infections occur because viruses spread rapidly among humans. Nineteen percent (19%) of the infected patients developed severe pneumonia and acute respiratory distress syndrome (ARDS). Hypoxemia usually occurs and patients may require oxygen therapy or mechanical ventilation (MV) support. In this article, recently published clinical experience and observational studies were reviewed. Corresponding respiratory therapy regarding different stages of infection is proposed. Infection control principles and respiratory strategies including oxygen therapy, non-invasive respiratory support (NIRS), intubation evaluation, equipment preparation, ventilator settings, special maneuvers comprise of the prone position (PP), recruitment maneuver (RM), extracorporeal membrane oxygenation (ECMO), weaning and extubation are summarized. Respiratory equipment and device disinfection recommendations are worked up. We expect this review article could be used as a reference by healthcare workers in patient care while minimizing the risk of environmental contamination.

The effect of saline versus air for cuff inflation on the incidence of high intra-cuff pressure in paediatric MicroCuff® tracheal tubes: a randomised controlled trial

The use of cuffed tracheal tubes in paediatric anaesthesia is now common. The use of nitrous oxide in anaesthesia risks excessive tracheal tube cuff pressures, as nitrous oxide can diffuse into the cuff during the course of surgery. The aim of this single-centre, prospective, randomised controlled trial was to compare the effect of saline versus air for the inflation of tracheal tube cuffs on the incidence of excessive intra-operative cuff pressure in children undergoing balanced anaesthesia with nitrous oxide. Children (age ≤ 16 y) were randomly allocated to receive either saline (saline group) or air (air group) to inflate the cuff of their tracheal tube. The pressure in the tracheal tube cuff was measured during surgery and brought down to the initial inflation level if it breached a safe limit (25 cmH₂ O). Post-extubation adverse respiratory events were noted. Data from 48 patients (24 in each group), aged 4 months to 16 y, were analysed. The requirement for reduction in intra-cuff pressure occurred in 1/24 patients in the saline group, compared with 16/24 patients in the air group (p < 0.001). The incidence of extubation-related adverse events was similar in the saline and air groups (15/24 vs. 13/24, respectively; p = 0.770). The use of saline to inflate the cuff of paediatric cuffed tubes reduces the incidence of high intra-cuff pressures during anaesthesia. This may provide a pragmatic extra safety barrier to help reduce the incidence of excessive tracheal cuff pressure when nitrous oxide is used during paediatric anaesthesia.

Alkalinized Lidocaine Preloaded Endotracheal Tube Cuffs Reduce Emergence Cough After Brief Surgery: A Prospective Randomized Trial

BACKGROUND

Alkalinized lidocaine in the endotracheal tube (ETT) cuff decreases the incidence of cough and throat pain on emergence after surgery lasting more than 2 hours. However, alkalinized lidocaine needs 60-120 minutes to cross the ETT cuff membrane; therefore, its usefulness in shorter duration surgery is unknown. This prospective double-blind randomized controlled trial tested the hypothesis that alkalinized lidocaine would reduce the incidence of emergence cough after surgeries lasting <120 minutes.

METHODS

After local ethics board approval, American Society of Anesthesiologists I-III patients consented to be randomized into 1 of 2 groups receiving either alkalinized lidocaine (group AL) or saline (group S) to inflate the ETT cuff. Cuffs were prefilled >90 minutes before intubation with either 2 mL of 2% lidocaine and 8 mL of 8.4% bicarbonate (group AL) or 10 mL of normal saline (group S). Cuffs were emptied immediately before intubation. After intubation, either 2 mL of 2% lidocaine (AL) or 2 mL of saline (S) were injected into the cuff. Additional 8.4% bicarbonate (AL) or saline (S) was injected into the cuff until there was no air leak. Anesthesia was maintained using desflurane, rocuronium, and either fentanyl or sufentanil to maintain vital signs within 20% of baseline values. Opioids administered in prophylaxis of extubation cough were proscribed. A standardized "no touch" emergence technique was used. A blinded assessor noted any cough above 0.2 minimum alveolar concentration (MAC) of expired desflurane. At 0.2 MAC, once every 30 seconds, the patient was instructed to open his eyes and extubation occurred once a directed response was noted.

RESULTS

A total of 213 patients were randomized and 100 patients in each group completed the experimental protocol. The incidence of extubation cough in group AL was 12%, significantly lower (1-sided P = .045) than the 22% incidence in group S. The 1-tailed risk ratio for cough in group AL was 0.55 (0-0.94, P = .045). Total amount of opioids administered (P = .194), ETT cuff preloading times (P = .259), and extubation times (P = .331) were not significantly different between groups. The average duration of surgery was 59 ± 28 minutes in group AL and 52 ± 29 minutes in group S (P = .057).

CONCLUSIONS

Alkalinized lidocaine in the ETT cuff significantly decreased general anesthesia emergence cough after surgeries with an average duration of slightly <1 hour.

Efficacy and Safety of Using Air Versus Alkalinized 2% Lignocaine for Inflating Endotracheal Tube Cuff and Its Pressure Effects on Incidence of Postoperative Coughing and Sore Throat

Background and Objective:

We wished to compare the endotracheal tube (ETT) cuff pressure inflated with air or alkalinized lignocaine during anesthesia and evaluate clinical symptoms such as coughing and sore throat (postoperative sore throat [POST]) following tracheal extubation.

Materials and Methods:

This was a prospective randomized controlled study conducted in a tertiary care set up over a period of 1 year. We included 100 patients in age group of 18–65 years posted for elective surgeries of duration more than 90 min under general anesthesia with N₂O-O₂ mixture. Patients were randomized using computer-generated randomization table into air and lignocaine group. The ETT cuff was inflated with air or alkalinized lignocaine (2% lignocaine with 7.5% sodium bicarbonate, in the proportions of 19.0:1.0 ml) to the volume that prevented air leak using cuff pressure manometer. After extubation, an independent observer blinded to study group recorded the presence or absence of coughing and POST at immediately, 1 h and 24 h postoperatively.

Results:

Demographic data, baseline characteristics (American Society of Anesthesiologists grade, intracuff volume/cuff pressure at start of surgery), and duration of anesthesia were comparable among study groups (P > 0.05). Cuff pressure and volume achieved in the end of surgery were much higher in air group as compared to lignocaine group (P < 0.05). Incidence of coughing and POST at immediately, 1 h and 24 h postoperatively was significantly higher in air group compared to lignocaine group. Impact of duration of anesthesia on rise in cuff pressure was significantly higher in air group and its effect on cuff-induced laryngotracheal morbidity was significant in both air and lignocaine group.

Conclusion:

This study showed the significance of use of alkalinized 2% lignocaine in prevention of rise of cuff pressure and incidence of coughing and POST. Duration of anesthesia has also a significant effect on incidence of postoperative trachea-laryngeal morbidity.

The effects of tracheal tube cuffs filled with air, saline or alkalinised lidocaine on haemodynamic changes and laryngotracheal morbidity in children: a randomised, controlled trial

We studied the effects of tracheal tube cuffs filled with air, saline or alkalinised lidocaine on haemodynamic changes during tracheal extubation and postoperative laryngotracheal morbidity in children. We randomly allocated 164 children aged 3-13 years undergoing general anaesthesia to one of four groups; tracheal tube cuffs filled with air (n = 41); saline (n = 41); alkalinised lidocaine 0.5% (n = 41); or alkalinised lidocaine 1% (n = 41). Intracuff pressure was monitored and maintained below 20 cmH₂ O. The mean (SD) increases in systolic blood pressure after tracheal extubation compared with before extubation were 10.9 (10.8) mmHg, 7.3 (17.7) mmHg, 4.1 (10.5) mmHg and 1.9 (9.5) mmHg in the air, saline, 0.5% and 1% alkalinised lidocaine groups, respectively (p = 0.021). The mean (SD) increases in diastolic blood pressure after tracheal extubation compared with before extubation were 3.9 (9.7) mmHg, 7.9 (14.6) mmHg, 0.7 (10.4) mmHg and 3.6 (6.9) mmHg in the air, saline, 0.5% and 1% alkalinised lidocaine groups, respectively (p = 0.019). The mean (SD) increases in heart rate after tracheal extubation compared with before extubation were 14.2 (7.6) beats.min^-1 , 15.5 (13.1) beats.min^-1 , 5.2 (9.6) beats.min^-1 and 4.1 (6.6) beats.min^-1 in the air, saline, 0.5% and 1% alkalinised lidocaine groups, respectively (p < 0.001). The incidence of sore throat 8 h after tracheal extubation was 22.0% in the air-filled group, 9.8% in the saline group, 4.9% in the 0.5% alkalinised lidocaine group and 2.4% in the 1% alkalinised lidocaine group, p = 0.015. We conclude that filling the tracheal tube cuff with alkalinised lidocaine-filled reduces the haemodynamic response to tracheal extubation and postoperative laryngotracheal morbidity in children.

Effect of Intracuff Lidocaine on Postoperative Sore Throat and the Emergence Phenomenon: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Postoperative sore throat and other airway morbidities are common and troublesome after endotracheal tube intubation general anesthesia (ETGA). We propose lidocaine as endotracheal tube (ETT) cuff inflation media to reduce the postintubation-related emergence phenomenon.

METHODS

We searched PubMed, EMBASE, and Cochrane databases systematically for randomized controlled trials (RCTs) that have investigated the outcome of intracuff lidocaine versus air or saline in patients receiving ETGA. Using a random-effects model, we conducted a meta-analysis to assess the relative risks (RRs) and mean difference (MD) of the incidence and intensity of relevant adverse outcomes.

RESULTS

We reviewed nineteen trials, which comprised 1566 patients. The incidence of early- and late-phase postoperative sore throat (POST), coughing, agitation, hoarseness, and dysphonia decreased significantly in lidocaine groups, with RRs of 0.46 (95% confidence interval [CI]: 0.31 to 0.68), 0.41 (95% CI: 0.25 to 0.66), 0.43 (95% CI: 0.31 to 0.62), 0.37 (95% CI: 0.25 to 0.55), 0.43 (95% CI: 0.29 to 0.63), and 0.19 (95% CI: 0.08 to 0.5), respectively, when compared with the control groups. The severity of POST also reduced significantly (mean difference [MD] -16.43 mm, 95% CI: -21.48 to -11.38) at 1 h and (MD -10.22 mm, 95% CI: -13.5 to -6.94) at 24 h. Both alkalinized and non-alkalinized lidocaine in the subgroup analyses showed significant benefits in emergence phenomena prevention compared with the control.

CONCLUSION

Our results indicate that both alkalinized and non-alkalinized intracuff lidocaine may prevent and alleviate POST and postintubation-related emergence phenomena.

Lidocaine for preventing postoperative sore throat

BACKGROUND

Sore throat is a common side-effect of general anaesthesia and is reported by between 30% and 70% of patients after tracheal intubation. The likelihood of a sore throat varies with the type, diameter, and cuff pressure of the endotracheal tube used. If intubation is essential, it may be helpful to give drugs prophylactically to alleviate postoperative sore throat. Local anaesthetics and steroids have been used for this purpose. This review was originally published in 2009 and was updated in 2015.

OBJECTIVES

The objective of this review was to evaluate the efficacy and any harm caused by topical and systemic lidocaine used prophylactically to prevent postoperative sore throat in adults undergoing general anaesthesia with endotracheal intubation.

SEARCH METHODS

We searched CENTRAL (The Cochrane Library 2013, Issue 9), MEDLINE (January 1966 to October 2013), and EMBASE (1980 to October 2013). We also contacted manufacturers and researchers in the field. The original search was undertaken in June 2007. We reran the search in February 2015 and found four studies of interest. We will deal with those studies when we next update the review.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) of topical and systemic prophylactic lidocaine therapy versus control (using air or saline) that reported on the risk and severity of postoperative sore throat as an outcome.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. We contacted study authors for additional information, such as the risk of any adverse effects.

MAIN RESULTS

We included 19 studies involving 1940 participants in this updated review. Of those 1940 participants, 952 received topical or systemic lidocaine therapy and 795 were allocated to the control groups. Topical and systemic lidocaine therapy appeared to reduce the risk of postoperative sore throat (16 studies, 1774 participants, risk ratio (RR) was 0.64 (95% confidence interval (CI) 0.48 to 0.85), the quality of the evidence was low), although when only high-quality trials were included (eight studies, 814 participants) the effect was no longer significant (RR 0.71, 95% CI 0.47 to 1.09). Lidocaine given systemically in two studies (320 participants) did not reveal evidence of an effect (RR 0.44, 95% CI 0.19 to 1.05 ). The severity of sore throat as measured on a visual-analogue scale (VAS) was reduced by lidocaine therapy (six trials, 611 participants, (mean difference (MD) -10.80, 95% CI -14.63 to -6.98). The adverse effects of lidocaine were not reported in these studies, though toxicity is generally rare.

AUTHORS' CONCLUSIONS

In our revised systematic review, although the results of included studies show generally positive results, they should be interpreted carefully. The effect size of lidocaine appeared to be affected by study quality; drug concentration; route of administration; management of cuff pressure during anaesthesia; the included population; and the type of outcome measured.

Intravenous dexamethasone versus ketamine gargle versus intravenous dexamethasone combined with ketamine gargle for evaluation of post-operative sore throat and hoarseness: A randomized, placebo-controlled, double blind clinical trial

BACKGROUND

Sore throat and hoarseness are the most frequent subjective complaints after tracheal intubation for general anesthesia. We conducted a prospective, randomized, double-blind, placebo controlled study to evaluate the efficacy of intravenous (IV) dexamethasone plus ketamine gargle for reducing the incidence and severity of post-operative sore throat (POST) and hoarseness.

MATERIALS AND METHODS

140 patients (aged 16-65 year) scheduled for elective surgery were enrolled. Patients were randomly allocated into four groups of 35 subjects each: Group K, gargled 40 mg ketamine in 30 ml saline; Group D, were infused 0.2 mg/kg IV dexamethasone; Group KD, gargled 40 mg ketamine in 30 ml saline plus 0.2 mg/kg IV dexamethasone; Group P (placebo) that received saline (gargle and IV). POST was graded at 0, 2, 4, 8, 16 and 24 h after operation on a four-point scale (0-3).

RESULTS

The incidence and severity of POST were significantly lower in Group KD, compared with the other groups at all times after tracheal extubation for up to 24 h (P < 0.05). Also the incidence and severity of hoarseness were significantly lower in each Groups of KD and K and D compared with group placebo (P < 0.05).

CONCLUSION

The prophylactic use of 0.2 mg/kg of IV dexamethasone plus ketamine gargle significantly reduced the incidence and severity of POST compared with using each of these drugs alone or using placebo.

The efficacy of lidocaine to prevent laryngospasm in children: a systematic review and meta-analysis

The purpose of this meta-analysis was to determine the efficacy of lidocaine in preventing laryngospasm during general anaesthesia in children. An electronic search of six databases was conducted. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were adhered to. We included randomised controlled trials reporting the effects of intravenous and/or topical lidocaine on the incidence of laryngospasm during general anaesthesia. Nine studies including 787 patients were analysed. The combined results demonstrated that lidocaine is effective in preventing laryngospasm (risk ratio (RR) 0.39, 95% CI 0.24-0.66; I(2)  = 0). Subgroup analysis revealed that both intravenous lidocaine (RR 0.34, 95% CI 0.14-0.82) and topical lidocaine (RR 0.42, 95% CI 0.22-0.80) lidocaine are effective in preventing laryngospasm. The results were not affected by studies with a high risk of bias. We conclude that, both topical and intravenous lidocaine are effective for preventing laryngospasm in children.

In vitro evaluation of diffusion of lidocaine and alkalinized lidocaine through the polyurethane membrane of the endotracheal tube

OBJECTIVES

Endotracheal tube (ETT) and its inflated cuff are likely to induce specific reactivity at the emergence time. In ICU, the tolerance of the ETT cuff could be a part of patient agitation and increased of sedation.

MATERIALS AND METHODS

Using specific ICU ETT cuff (thin polyurethane cuff), we perform an in vitro evaluation of diffusion of lidocaine and alkalinized lidocaine (L-B) across the PU cuff for a long duration. We evaluate the safety of this procedure by a daily injection into the cuff.

RESULTS

With lidocaine alone, we observed a low rate of diffusion through the cuff (<8% over 24h), whereas the L-B solution had a high diffusion (>90% over 24h). The released profiles were similar from day 0 to day 8, and no cuff rupture was reported over the 8-day study.

CONCLUSION

The safety, controlled release, and lack of deleterious effects on cuff membrane were confirmed. In case of unexpected cuff rupture, an adequate determination of the mixture allows to obtain a safe solution with the achievement of a physiological pH (7.4) and the small dose of lidocaine (40 mg).

The effects of lidocaine spray and intracuff alkalinized lidocaine on the occurrence of cough at extubation: a double-blind randomized controlled trial

PURPOSE

Our study aimed to evaluate the effects of lidocaine sprayed onto the larynx and/or injected into the tracheal tube cuff to decrease the incidence of cough at extubation and postoperative sore throat.

METHODS

One hundred twenty women scheduled for gynecological surgery < 120 min in duration were enrolled in this randomized double-blind prospective study. Prior to tracheal intubation, 4% lidocaine or 0.9% saline was sprayed onto the patients' supra- and subglottic areas. After tracheal intubation, the tracheal tube cuff was filled with either an alkalinized 2% lidocaine solution or 0.9% saline. This resulted in four groups: spray-cuff, spray-saline, saline-cuff, and saline-saline. A logistic regression comprising the two factors was used for analysis. The primary outcome was the incidence of cough at extubation. The secondary outcome was the incidence and severity of sore throat reported by patients at 15 min, 60 min, and 24 hr after tracheal extubation.

RESULTS

Cough occurred in 42%, 24%, 63%, and 69% of patients in the spray-cuff, spray-saline, saline-cuff, and saline-saline groups, respectively. The use of lidocaine spray decreased the incidence of cough at extubation (odds ratio = 0.256; 95% confidence interval 0.118 to 0.554; P < 0.001); however, the use of intracuff alkalinized lidocaine had no impact on the occurrence of cough (P = 0.471). Severity of sore throat was clinically low (visual analog scale [VAS] ≤ 3) in all groups. No significant difference was observed in hoarseness, dysphagia, nausea, or vomiting.

CONCLUSION

Sprayed lidocaine decreases the incidence of cough at tracheal extubation in surgeries of less than two hours. The use of alkalinized lidocaine into high-volume/low-pressure endotracheal cuffs had no impact on decreasing the incidence of cough or pain.

[Endotracheal tube cuff and nitrous oxide: bench evaluation and assessment of clinical practice]

OBJECTIVE

To evaluate the risk of over-inflation of endotracheal tube cuffs (ETC) when used with nitrous oxide (N(2)O); to assess the rate of under and over-inflation of ETC when they are inflated without a manometer; to survey anesthesiologists about how they prevent these risks.

METHODS

Nine types of endotracheal tube were studied on bench using various N(2)O concentrations; airway pressure levels and two sizes of trachea. Then, the rate and magnitude of over and under inflation pressure of ETC was assessed in our clinical practice. Finally, a national survey assessed how anesthesiologists prevented misuse of endotracheal tube with N(2)O.

RESULTS

Pressure in ETC rose sharply using N(2)O, up to more than 40 cmH(2)O in six over nine tube types. Only two tube types (Mallinckrodt Hi-Lo Brandt and Lanz) were immune regarding N(2)O. Pratice study showed that ETC over inflation (>30 cmH(2)O) and under inflation (<20 cmH(2)O) was observed in 50 and 31 % of patients, respectively when cuff was inflated without a manometer. In France, a minority of anesthesiologists inflated ETC with a manometer (41 %) because in 61 % of theatres only manometers were available.

CONCLUSION

There are risks induced by the use of N(2)O with tracheal tubes. This study provides data to sensitize users to these risks.

Endotracheal tube cuff lidocaine is not superior to intravenous lidocaine in short pediatric surgeries

BACKGROUND

Instillation of lidocaine into the endotracheal tube cuff is a method with reported efficiency in promoting a smoother emergence from anesthesia with endotracheal intubation. However, whether or not this method is helpful in children and in surgeries with short duration has not been investigated previously.

METHODS

176 ASA I-II children undergoing adenotonsillectomy were enrolled in this prospective, double-blind, randomized clinical trial. Patients were randomly allocated to two groups. Patients in the ECL group (n=88) were injected 2% lidocaine into their endotracheal tube cuff and received saline (1.5mg/kg) intravenously. The IVL group (n=88) received 1.5mg/kg of 2% lidocaine intravenously and saline into the endotracheal tube cuff. In both groups, intra-cuff injections were initiated immediately after insertion of the endotracheal tube and terminated before the cuff pressure reached 20 cmH(2)O. The parameters measured were: coughing (graded by a scale of 3 at the time of extubation), systolic and diastolic blood pressures and heart rate (from the time of extubation up to 5 min after extubation at 1-min intervals), and laryngospasm (defined as the presence of hoarseness or absence of airflow).

RESULTS

The groups were not different in sex, age, weight, height, body mass index, anesthesia duration, and baseline hemodynamic parameters. The grade of coughing was significantly higher in the ECL group. The incidence of laryngospasm and hemodynamic trends did not differ between the groups.

CONCLUSIONS

Our results indicate that intra-cuff lidocaine may not be beneficial in children and in surgeries with a short duration.

Lidocaine for preventing postoperative sore throat

BACKGROUND

Sore throat is a common side effect of general anaesthesia and is reported by between 30% and 70% of patients after tracheal intubation. The likelihood of a sore throat varies with the type, diameter, and cuff pressure of the endotracheal tube used. If intubation is essential, it may be helpful to give drugs prophylactically to alleviate postoperative sore throat. Local anaesthetics and steroids have been used for this purpose.

OBJECTIVES

The objective of this review was to evaluate the effectiveness and any harms of topical and systematic lidocaine for the prevention of postoperative sore throat in adults undergoing endotracheal intubation as part of general anaesthesia.

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library 2007, Issue 3), MEDLINE (January 1966 to June 2007), and EMBASE (1980 to June 2007). We also contacted manufacturers and researchers in the field.

SELECTION CRITERIA

We included randomized controlled trials of topical and systemic prophylactic lidocaine therapy versus control (using air or saline) that reported on the risk and severity of postoperative sore throat as an outcome.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. We contacted study authors for additional information, such as the risk of adverse effects.

MAIN RESULTS

We included 1232 patients from 15 studies; 672 patients received topical or systemic lidocaine therapy and 560 patients were allocated to the control group. Both the topical and systemic lidocaine therapy significantly reduced the risk of postoperative sore throat (risk ratio (RR) 0.58; 95% confidence interval (CI) 0.41 to 0.82). To evaluate the severity of sore throat on a visual analogue scale (VAS), 219 patients received topical or systemic lidocaine therapy and 152 patients were allocated to the control groups. The severity of sore throat was reduced (mean difference (MD) -11.9; 95% CI -16.44 to -7.32), an effect that neared statistical significance. The adverse effects of lidocaine were not reported in these studies.

AUTHORS' CONCLUSIONS

Our systematic review establishes the effectiveness of topical and systemic lidocaine for the prevention of postoperative sore throat resulting from intubation. The risk and severity of postoperative sore throat tended to be reduced. The effect size of lidocaine appeared to be affected by drug concentration and route of administration; management of cuff pressure during anaesthesia; the included population; and the type of outcome measured.

Recent trends in Brazilian medical research. An overview

This article reviews 69 original research articles published in 6 Brazilian Medical Journals recently incorporated into the Institute for Scientific Information Journal of Citation Reports, with a view of making them comprehensively available to the readership of CLINICS within a subject category division. We expect this review to increase the visibility of a wide specter of original Brazilian research which may otherwise remain relatively unseen by the interested readership.