Lidocaine for preventing postoperative sore throat

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.

Comparison Prophylactic Effects of Gargling Different Doses of Ketamine on Attenuating Postoperative Sore Throat: A Single-Blind Randomized Controlled Trial

Context:

Postoperative sore throat (POST) is a common annoying problem following endotracheal (ET) intubation.

Aims:

Comparing the impact of low and high doses of ketamine gargle on lowering POST incidence and severity.

Settings and Design:

96 patients selected for septoplasty surgery under general anesthesia were investigated through a single-blind randomized controlled trial.

Methods:

This study was performed on three equal groups. Group K and G gargled 50 and 100 mg ketamine, respectively, solved in normal saline and group C gargled pure normal saline for 30 s at 5 min before tracheal intubation. POST severity measured immediately after the entrance to the postanesthetic care unit (PACU) and then 2 h, 4 h, 8 h, and 24 h after operation.

Statistical Analysis Used:

Collected data were analyzed by the Chi-square test, Mann-Whitney test, Kruskal-Wallis test, one-way analysis of variance (ANOVA) and Friedman test using SPSS version 20.

Results:

POST incidence and severity in group C were significantly higher than both K and G groups at all times. Although significant differences between low and high doses of ketamine were acknowledged at 8 h post-operation, 100 mg ketamine could attenuate POST severity further than 50 mg at all times.

Conclusions:

It seems that 100 mg outperformed 50 mg ketamine without rising complications and dissatisfaction for subjects. So, it gives us a powerful reason to suggest gargling 100 mg ketamine for lessening POST incidence and severity.

Comparison of the efficacy of supraglottic airway devices in low-risk adult patients: a network meta-analysis and systematic review

Numerous supraglottic airway device (SADs) have been designed for adults; however, their relative efficacy, indicated by parameters such as adequacy of sealing, ease of application, and postinsertion complications, remains unclear. We conducted a systematic review and network meta-analysis to evaluate the efficacy of various SADs. We searched electronic databases for randomized controlled trials comparing at least two types of SADs published before December 2019. The primary outcomes were oropharyngeal leak pressure (OLP), risk of first-attempt insertion failure, and postoperative sore throat rate (POST). We included 108 studies (n = 10,645) comparing 17 types of SAD. The Proseal laryngeal mask airway (LMA), the I-gel supraglottic airway, the Supreme LMA, the Streamlined Liner of the Pharynx Airway, the SoftSeal, the Cobra Perilaryngeal Airway, the Air-Q, the Laryngeal Tube, the Laryngeal Tube Suction II, the Laryngeal Tube Suction Disposable, AuraGain, and Protector had significantly higher OLP (mean difference ranging from 3.98 to 9.18 cmH₂O) compared with that of a classic LMA (C-LMA). The Protector exhibited the highest OLP and was ranked first. All SADs had a similar likelihood of first-attempt insertion failure and POST compared with the C-LMA. Our findings indicate that the Protector may be the best SAD because it has the highest OLP.Systematic review registration PROSPERO: CRD42017065273.

Effect of intravenous lidocaine on short-term pain after hysteroscopy: a randomized clinical trial

Background

The role of intravenous lidocaine infusion in endoscopic surgery has been previously evaluated for pain relief and recovery. Recently, it has been shown to reduce postoperative pain and opioid in patients undergoing endoscopic submucosal dissection. Similar to endoscopic submucosal dissection, operative hysteroscopy is also an endoscopic surgical procedure within natural lumens. The present study was a randomized clinical trial in which we evaluated whether intravenous lidocaine infusion would reduce postoperative pain in patients undergoing hysteroscopic surgery.

Objective

To evaluate whether intravenous lidocaine infusion could reduce postoperative pain in patients undergoing operative hysteroscopy.

Methods

Eighty-five patients scheduled to undergo elective hysteroscopy were randomized to receive either an intravenous bolus of lidocaine 1.5 mg.kg^-1 over 3 minutes, followed by continuous infusion at a rate of 2 mg.kg^-1. h^-1 during surgery, or 0.9% normal saline solution at the same rate. The primary outcome was to evaluate postoperative pain by Visual Analog Scale (VAS). Secondary outcomes included remifentanil and propofol consumption.

Results

In the lidocaine group, the VAS was significantly lower at 0.5 hour (p = 0.008) and 4 hours (p = 0.020). Patients in the lidocaine group required less remifentanil than patients in the control group (p < 0.001). However, there was no difference between the two groups in the propofol consumption. The incidence of throat pain was significantly lower in the lidocaine group (p = 0.019). No adverse events associated with lidocaine infusion were discovered.

Conclusion

Intravenous lidocaine infusion as an adjuvant reduces short-term postoperative pain in patients undergoing operative hysteroscopy.

Effect of topical ropivacaine on the response to endotracheal tube during emergence from general anesthesia: a prospective randomized double-blind controlled study

Background

The airway reflex such as cough is common accompanied with severe fluctuations of hemodynamics during emergence. This prospective double-blind randomized controlled trial tested the hypothesis that topical ropivacaine may reduce extubation response and postoperative sore throat.

Methods

Fifty-four patients undergoing thyroidectomy were randomly assigned to two groups. The patients in Group R were received 0.75% ropivacaine, which was sprayed on the tracheal mucosa, epiglottis, tongue base, and glottis to achieve uniform surface anesthesia. As control, patients in Group C were received the same volume saline. The primiary outcome was the incidence and grade of cough during peri-extubation.

Results

The incidence (34.62% vs. 76.92%, P = 0.002) of cough during extubation were lower in Group R compared to Group C. Meanwhile, the sore throat visual acuity score at 12 h after surgery was lower in Group R than that in Group C (2.00 vs. 3.50, P = 0.040).

Conclusion

Topical anesthesia with 0.75% ropivacaine before intubation can significantly reduce the incidence of cough during peri-extubation. Meanwhile, it reduced hemodynamic fluctuations and postoperative throat pain without influence patients recovery.

Trial registration

Chinese Clinical Trial Registry, ChiCTR1800014412 (date of registration January 2018).

Risk factors for postoperative throat pain after general anaesthesia with endotracheal intubation at the University of Gondar Teaching Hospital, Northwest Ethiopia, 2014

Introduction

Postoperative sore throat is listed from the top as patients’ most undesirable outcome in the postoperative period. It is believed to originate from mucosal dehydration or edema, tracheal ischemia secondary to the pressure of endotracheal tube cuffs, aggressive oropharyngeal suctioning, and mucosal erosion from friction between delicate tissues and the endotracheal tube. Even if the problem was indicated in many literatures, it has never been studied in our country. The study aimed to assess prevalence and factors associated with postoperative sore throat among patients who were operated under general anesthesia with endotracheal intubation.

Methods

Hospital based cross sectional study was conducted from February 25 - April 10, 2014 in Gondar University hospital. Patient interview and chart review were employed for data collection. Bivariate and multivariate logistic regressions were used to determine the association.

Results

A total of 240 out of 299 patients were included in this study with a response rate of 80.3%. The prevalence of postoperative sore throat within 48 hours after operation was 59.6%. Factors which had association with postoperative sore throat from the multivariate logistic regression were female sex (AOR = 3.3, 95% CI: 1.07, 10.375), repeated number of attempts to intubate (AOR = 3.291, 95% CI: 1.658, 6.531), and the use of nasogastric tube (AOR = 0.41, 95% CI: 0.174, 0.965) respectively.

Conclusion

The prevalence of postoperative sore throat was high in Gondar University Hospital. Awareness creation about the problem should be made for health professionals and postoperative sore throat management protocol need to be introduced.

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.

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.

Magnesium and Ketamine Gargle and Postoperative Sore Throat

Background:

Postoperative sore throat is one of the most common complications after endotracheal intubation. Both Ketamine and magnesium can block N-methyl-D-aspartic acid (NMDA) receptors and provide central and local analgesia.

Objectives:

To compare the effect of magnesium sulfate and ketamine gargle on the incidence and severity of postoperative sore throat.

Patients and Methods:

A total of 100 patients candidate for emergency acute appendicitis surgery were enrolled in the study. Patients in ketamine group received ketamine gargle (0.5 mg/kg) and magnesium group received magnesium sulfate gargle (20 mg/kg up to 30 mL dextrose water 20%) 15 minutes before the operation. Patient complaint of postoperative sore throat, and its severity measured by visual analogue scale (VAS) were recorded at baseline in recovery room, and then 2, 4, and 24 hours after operation.

Results:

There were no significant differences between age, sex, and body mass index (BMI) between two groups of patients. Hemodynamics of patients, including blood pressure, respiratory rate, oxygen saturation %, and conscious state were not significantly different (P > 0.05). Number of patients with sore throat were significantly lower in magnesium group compared to ketamine group at 2 (P = 0.032), 4 (P = 0.02), and 24 hours (P = 0.01) after the operation. Sore throat pain score (VAS) was significantly lower in magnesium group compared to ketamine group at 2 (P = 0.019), 4 (P = 0.028), and 24 hours (P = 0.014) after the operation.

Conclusions:

Magnesium at low dose decreases sore throat and pain severity more effectively compared to ketamine gargle.

Evaluation of preoperative Strepsils lozenges on incidence of postextubation cough and sore throat in smokers undergoing anesthesia with endotracheal intubation

Post-operative sore throat (POST) is an undesirable side effect of endotracheal intubation. Pharmacological and non-pharmacological measures have been utilized for minimizing the morbidity caused by POST. We have tested use of Strepsils lozenges in providing efficacy for decreasing POST in smokers presenting for surgery under general anesthesia with endotracheal intubation.

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).

Intracuff alkalized lidocaine reduces sedative/analgesic requirements for mechanically ventilated patients

Background:

The objective of this study is to investigate the effect of intracuff alkalized lidocaine on sedative/analgesic requirements for mechanically ventilated patients and its consequence on patient-ventilator interaction.

Materials and Methods:

A total of 64 patients who expected to require ventilatory support for a period of more than 48 h were randomly assigned to groups S and L. In group S, the endotracheal tube (ETT) cuffs were inflated with normal saline. In group L, the ETT cuffs were inflated with lidocaine 2% and sodium bicarbonate 8.4%. The investigator and the surgical intensive care unit staff were blinded to the nature of cuff-filled solutions. Sedation was maintained with propofol and fentanyl infusions. The total requirements for propofol and fentanyl, frequency and severity of cough and number of ineffective triggering during the first 24 h of mechanical ventilation were recorded.

Results:

There was a significant reduction (about 30%) in the requirements for propofol and fentanyl in patients who received intracuff alkalinized lidocaine; P < 0.001. The frequency and severity of cough were significantly lower in group L compared with group S and the frequency of ineffective triggering was significantly lower in group L; P < 0.001 for both comparisons.

Conclusion:

Intracuff alkalized lidocaine increases ETT tolerance and hence, decreases sedatives/analgesics requirements for mechanically ventilated patients. This results in improved patient-ventilator synchronization.

Dexamethasone for preventing postoperative sore throat: a meta-analysis of randomized controlled trials

BACKGROUND

Postoperative sore throat (POST) is a common complication following tracheal intubation. The effectiveness of prophylactic dexamethasone on POST needs further elucidation.

AIMS

To evaluate the effectiveness and safety of intravenous dexamethasone for the prevention of POST in patients undergoing endotracheal intubation.

METHODS

Studies were identified by literature searches of PubMed, Embase, and the Cochrane database. Systematic review was performed by two independent investigators.

RESULTS

We summarized 7 RCTs including 727 participants. Intravenous dexamethasone significantly reduced the risk of POST at 24 h [pooled risk ratio (RR) = 0.676; 95 % confidence interval (CI) 0.494-0.925; P = 0.014; heterogeneity test, I (2) = 45.8 %], as well as alleviating its severity [standardized mean difference (SMD) = -1.15; 95 % CI -1.86 to -0.45; P = 0.002; heterogeneity test, I (2) = 91.7 %]. Further sub-group analysis indicated a significant relationship between dexamethasone and reduced risk of POST when its dose was over 0.1 mg/kg. No severe adverse effects were reported.

CONCLUSIONS

Our results suggest that intravenous dexamethasone reduces the risk and severity of POST from intubation at 24 h. The effective dosage of dexamethasone for preventing the risk of POST appeared to be over 0.1 mg/kg.

Effects of intravenous diclofenac on postoperative sore throat in patients undergoing laparoscopic surgery at Aga Khan University Hospital, Nairobi: a prospective, randomized, double blind controlled trial

BACKGROUND

postoperative sore throat is the commonest complication after endotracheal intubation. The efficacy of intravenous non-steroidal anti-inflammatory drugs in alleviating postoperative sore throat has not been investigated.

OBJECTIVE

To evaluate the effect of intravenous diclofenac sodium on the occurrence and severity of postoperative sore throat.

METHODS

42 in-patients scheduled for laparoscopic surgery were randomized into two equal groups to receive either a single dose of 75mg intravenous diclofenac sodium in addition to standard treatment taken at our hospital for the prevention of postoperative sore throat or to receive standard treatment only. All patients were interviewed postoperatively at 2, 6 and 18 hours. Data of the baseline characteristics, the incidence and severity of sore throat were collected. If sore throat was present, a Visual Analogue Score was used to assess its severity.

RESULTS

the baseline characteristics of the participants were similar. The majority of the patients undergoing laparoscopic surgery were women. There was no statistically significant difference in the occurrence or severity of postoperative sore throat between the diclofenac and standard treatment groups at 2, 6 and 18 hours postoperatively.

CONCLUSION

Intravenous diclofenac sodium does not reduce the occurrence or severity of postoperative sore throat.

The impact of prophylactic intravenous lidocaine on opioid-induced cough: a meta-analysis of randomized controlled trials

BACKGROUND

Opioids are commonly used for general anesthesia, but reflex cough can occur after an intravenous injection. We have performed a meta-analysis of randomized controlled trials (RCTs) that evaluated the effectiveness and safety of prophylactic lidocaine administered intravenously (IV) on opioid-induced cough (OIC) during induction in patients undergoing general anesthesia.

METHODS

We searched three bibliographic databases (PubMed, Embase, and the Cochrane Central Register of Controlled Trials) to identify studies meeting a priori inclusion criteria and also conducted a secondary reference review. The information used to calculate the relationship between lidocaine prophylaxis and the risk and severity of OIC was extracted by two principal investigators, respectively.

RESULTS

Six RCTs with a total of 1,740 participants were included in this meta-analysis. Overall, prophylactic lidocaine administered IV reduced both the risk of OIC [pooled risk ratio (RR) 0.471; 95 % confidence interval (CI) 0.355-0.625; P = 0.074; heterogeneity test, I (2) = 50.3 %] and its severity (weighed mean difference -0.316; 95 % CI -0.480 to -0.151; P = 0.038; heterogeneity test, I (2) = 60.5 %). Sub-group analysis indicated a significant reduction in the incidence of both fentanyl-induced cough (FIC) and remifentanil-induced cough (RIC), but it appeared that lidocaine only alleviated the severity of FIC. Further sub-group analysis indicated that the lowest effect dose of lidocaine for preventing the prevalence of OIC was 0.5 mg/kg. No severe adverse effects were reported.

CONCLUSIONS

Our meta-analysis establishes the effectiveness of prophylactic lidocaine administered IV for the prevention of OIC during induction. The lowest effective dose of lidocaine on the risk of OIC appeared to be 0.5 mg/kg.

The size of endotracheal tube and sore throat after surgery: a systematic review and meta-analysis

BACKGROUND

Recent studies showed that sore throat following endotracheal intubation was a common problem following surgery. The objective of this systematic review and meta-analysis of published randomized controlled trials (RCTs) or cohort studies was to estimate whether the size of endotracheal tube (ETT) affects the incidence of postoperative sore throat (POST) after general anesthesia.

METHODS

The following databases were searched electronically: PubMed (updated to Dec 2012), EMBASE (updated to 15 Dec 2012), Google scholar, World Health Organization International Clinical Trials Registry Platform (Jul 2011), Chinese BioMedical Literature Database (1978 to Jul 2011), and China National Knowledge Infrastructure (1994 to Jul 2011). Studies comparing the size of endotracheal tube for elective surgery were included.

RESULTS

Three trials with a total of 509 female patients were included in the current analysis. The size of ETT used were 6.0 mm and 7.0 mm. Pooled studies from these trials showed that the smaller size of ETT (6.0 mm) significantly decreased the incidence of POST in post-anesthesia care unit (PACU) (RR = 0.56, 95% CI 0.42-0.75, P<0.01) and at 24 h after surgery (RR = 0.69, 95% CI 0.48-0.99, P<0.05). A smaller size of ETT (6.0 mm) was associated with a lower incidence of PH in PACU (RR = 0.69, 95% CI 0.55-0.87, P<0.01), but did not affect the incidence of PH at 24 h after surgery (RR = 0.73, 95% CI 0.46-1.15, P>0.05).

CONCLUSION

Our meta-analysis suggests that patients under general anesthesia with a smaller size of ETT (6.0 mm) were associated with a lower incidence of POST in female patients. More studies with adequate numbers of patients were warranted to evaluate other size of ETT on the incidence of PH and POST after general surgery among different populations.

Effect of Intravenous Hydrocortisone on Preventing Postoperative Sore Throat Followed by Laryngeal Mask Airway Use in patients Undergoing Urogenital Surgeries

INTRODUCTION

Postoperative sore throat is a common complication which can lead to discomfort after operation and delay in patients' returning to normal daily activities. The present study was carried out to evaluate the influence of intravenous hydrocortisone on preventing postoperative sore throat followed by laryngeal mask airway use.

METHODS

Sixty patients who were scheduled to undergo urogenital surgery were divided into two groups. Five minutes before anesthesia induction, 100 mg of intravenous hydrocortisone or placebo with the same volume were given to the patients randomly. At the end of the operation and after LMAs were removed, patients were asked about having sore throat at hours 2, 4 and 24 after operation.

RESULTS

There were three and six cases of sore throat after operation in hydrocortisone and in placebo groups respectively which showed no significant statistical difference (P=0.472). No cases of moderate or severe pain were reported in any of the patients in both groups and no statistically significant difference was observed regarding pain severity in recovery, hours 2, 4 or 24 after operation.

CONCLUSION

Based on the statistical data obtained from this research, administrating intravenous hydrocortisone five minutes before anesthesia induction has no effect on postoperative sore throat severity and degree in urogenital surgeries.

A smaller endotracheal tube combined with intravenous lidocaine decreases post-operative sore throat - a randomized controlled trial

BACKGROUND

Post-operative sore throat (POST) has increasingly been a common clinical complication particularly in thyroid surgery. We conducted a trial to evaluate the effect of non-pharmacological [smaller-sized endotracheal tube (ETT)] combined with pharmacological intervention [lidocaine intravenous (i.v.)] on POST in women undergoing thyroid surgery.

METHODS

Two hundred and forty patients scheduled for thyroid surgery were randomly divided into four groups: Group A, ETT size 7.0 with saline; Group B, ETT size 6.0 with saline; Group C, ETT size 7.0 with lidocaine; Group D, ETT size 6.0 with lidocaine. Patients in Groups C and D received i.v. 1.5 mg/kg lidocaine that was filled in syringe up to 10 ml 5 min before induction of anaesthesia; whereas patients in Groups A and B received an equal volume of saline. The incidence and severity of POST were evaluated at 1, 6 and 24 h after tracheal extubation.

RESULTS

The highest incidence of POST occurred at 6 h after extubation in all groups. The incidence of POST was significantly lower in Group D compared with Groups A (23% vs. 62%, P < 0.01), B (23% vs. 42%, P = 0.03) and C (23% vs. 43%, P = 0.02) at 6 h after extubation. Group D had significantly decreased severity of POST compared with Groups A, B and C 6 and 24 h after extubation (P < 0.05).

CONCLUSION

Use of smaller-sized ETT combined with i.v. lidocaine decreases the incidence and severity of POST in women undergoing thyroid surgery.

Environmental and non-infectious factors in the aetiology of pharyngitis (sore throat)

OBJECTIVES

The aim of this review is to examine the causes, pathophysiology and experimental models of non-infectious pharyngitis (sore throat).

INTRODUCTION

The causes of sore throat can be infectious (viruses, bacteria, and fungi) or non-infectious, although the relative proportion of each is not well documented.

METHODS

A PubMed database search was performed for studies of non-infectious sore throat.

RESULTS AND CONCLUSIONS

Non-infectious causes of sore throat include: physico-chemical factors, such as smoking, snoring, shouting, tracheal intubation, medications, or concomitant illness; and environmental factors including indoor and outdoor air pollutants, temperature and humidity, and hazardous or occupational irritants. The pathophysiology underlying non-infectious sore throat is largely uncharacterised, although neurogenic inflammation looks to be a promising candidate. It is likely that there will be individual disposition factors or the coincidence of more than one irritant with possible--up to now unknown--interactions between them. Therefore, experimental models with defined conditions and objective endpoints are needed. A new model using cold dry air to directly induce pharyngeal irritation in humans, with pharyngeal lavage to measure biomarkers, may provide a useful tool for the study of mechanisms and treatment of non-infectious sore throat.

Impact of single centre status on estimates of intervention effects in trials with continuous outcomes: meta-epidemiological study

OBJECTIVE

To compare estimates of intervention effects between single centre and multicentre randomised controlled trials with continuous outcomes.

DESIGN

Meta-epidemiological study.

DATA SOURCES

26 meta-analyses totalling 292 randomised controlled trials (177 single centre, 115 multicentre) with continuous outcomes published between January 2007 and January 2010 in the Cochrane database of systematic reviews.

DATA EXTRACTION

Data were extracted on characteristics of trials, single or multicentre status, risk of bias using the risk of bias tool of the Cochrane Collaboration, and results.

DATA SYNTHESIS

The intervention effects were estimated with standardised mean differences. For each meta-analysis, random effects meta-regression was used to estimate the difference in standardised mean differences between single centre and multicentre trials. Differences in standardised mean differences were then pooled across meta-analyses by a random-effects meta-analysis model. A combined difference in standardised mean differences of less than 0 indicated that single centre trials showed larger treatment effects, on average, than did multicentre trials. Because single centre trials may be more prone to publication bias and may have lower methodological quality than multicentre trials, sensitivity analyses were done with adjustment for sample size and domains of the risk of bias tool.

RESULTS

Single centre trials showed larger intervention effects than did multicentre trials (combined difference in standardised mean differences -0.09, 95% confidence interval -0.17 to -0.01, P=0.04), with low heterogeneity across individual meta-analyses (I(2)=0%, between meta-analyses variance τ(2)=0.00). Adjustment for sample size slightly attenuated the difference (-0.08, -0.17 to 0.01). Adjustment for risk of bias yielded similar estimates with wider confidence intervals, some of them crossing 0 (-0.09, -0.17 to 0.00 for overall risk of bias).

CONCLUSIONS

On average, single centre clinical trials with continuous outcomes showed slightly larger intervention effects than did multicentre trials. Further research is needed to investigate potential causes of these differences.

Topical lidocaine reduces the risk of perioperative airway complications in children with upper respiratory tract infections

PURPOSE

To determine the effect of topically applied lidocaine on perioperative airway complications when using a laryngeal mask airway device (LMAD) in children either with or without a history of recent or ongoing upper respiratory tract infection (URI).

METHODS

In a randomized controlled double-blind trial, 34 children with a history of recent or ongoing URI and 32 non-URI children- all of whom were younger than age ten and scheduled to undergo minor surgical procedures-were randomly assigned to either a lidocaine or a placebo group. In the lidocaine group, an LMAD was lubricated with lidocaine gel before insertion, and a clear lubricating gel was used in the placebo group. The following data were recorded after standardized anesthesia induction and airway management: postoperative complications, such as coughing, desaturation, laryngospasm, and increased oral secretions, as well as length of stay in the postanesthetic recovery unit.

RESULTS

Children with URI had a lower overall perioperative complication rate if they received a lidocaine gel (35%) rather than placebo (94%) (P < 0.01). Also, the incidence of postoperative coughing was less (12% vs 53%; P = 0.03). In non-URI patients, lidocaine did not significantly reduce the rate of airway complications compared with placebo (17% vs 24%, respectively).

CONCLUSION

Lubrication of the LMAD with lidocaine gel reduces the incidence of airway complications in children with an upper respiratory tract infection.