Intravenous lidocaine infusion therapy and intraoperative neurophysiological monitoring in adolescents undergoing idiopathic scoliosis correction: A retrospective study

BACKGROUND

Posterior spinal instrumentation and fusion is an established surgical procedure for the correction of adolescent idiopathic scoliosis. Intraoperative neurophysiological monitoring is standard practice for this procedure. Anesthetic agents can have different, but significant, effects on neurophysiological monitoring outcomes.

AIM

To determine if intravenous lidocaine infusion therapy has an impact on the intraoperative neurophysiological monitoring during posterior spinal instrumentation and fusion for adolescent idiopathic scoliosis.

METHODS

Following ethical approval, we conducted a retrospective review of charts and the archived intraoperative neurophysiological data of adolescents undergoing posterior spinal instrumentation and fusion for adolescent idiopathic scoliosis. Intraoperative neurophysiological monitoring data included the amplitude of motor evoked potentials and the amplitude and latency of somatosensory evoked potentials. A cohort who received intraoperative lidocaine infusion were compared to those who did not.

RESULTS

Eighty-one patients were included in this analysis, who had surgery between February 4, 2016 and April 22, 2021: 39 had intraoperative intravenous lidocaine infusion and 42 did not. Based on hourly snapshot data, there was no evidence that lidocaine infusion had a detrimental effect on the measured change from baseline for MEP amplitudes in either lower (mean difference 41.9; 95% confidence interval -304.5 to 388.3; p = .182) or upper limbs (MD -279.0; 95% CI -562.5 to 4.4; p = .054). There was also no evidence of any effect on the measured change from baseline for SSEP amplitudes in either lower (MD 16.4; 95% CI -17.7 to 50.5; p = .345) or upper limbs (MD -2.4; 95% CI -14.5 to 9.8; p = .701). Finally, there was no evidence of a difference in time to first reportable neurophysiological event (hazard ratio 1.13; 95% CI 0.61 to 2.09; p = .680).

CONCLUSIONS

Data from these two cohorts provide preliminary evidence that intravenous lidocaine infusion has no negative impact on intraoperative neurophysiological monitoring during PSIF for adolescent idiopathic scoliosis.

Effect of intravenous lidocaine on outcomes in patients receiving propofol for gastrointestinal endoscopic procedures: an updated systematic review and meta-analysis

BACKGROUND

Gastrointestinal endoscopic procedures (GEPs) are frequently employed for the diagnosis and treatment of various gastrointestinal ailments. While propofol sedation is widely used during these procedures, there is a concern regarding its potential negative effects. Intravenous (IV) lidocaine has been suggested as an add-on to propofol sedation for GEPs, but current evidence on its efficiency and safety is limited. This systematic review and meta-analysis aimed to assess the impact of IV lidocaine on outcomes in patients receiving propofol during GEPs.

METHODS

Electronic databases were screened for randomized controlled trials (RCTs), published up to 31 March 2023, investigating the effectiveness of intravenous lidocaine addition to propofol sedation during GEPs.

RESULTS

A total of 12 RCTs involving 712 patients that received IV lidocaine and propofol for GEF and 719 patients that received propofol were analyzed. Adding IV lidocaine to propofol sedation led to significant reduction in pain after the procedure (standardized mean difference (SMD) =  - 0.91, 95% confidence interval [CI]; - 1.51 to - 0.32), decreased propofol usage (SMD =  - 0.89; 95% CI, - 1.31 to - 0.48), lower recovery time (SMD =  - 0.95 min; 95% CI, - 1.48 to - 0.43), and decreased pain score (SMD =  - 0.91; 95% CI, - 1.51 to - 0.32). The overall rate of adverse events was markedly less in the lidocaine group than in the control group (RR = 0.74; 95% CI, 0.56 to 0.99).

CONCLUSION

Our results show that IV lidocaine improves patient outcomes by reducing post-procedural pain, decreasing propofol usage, shortening recovery time, and lowering pain scores. This study provides compelling evidence supporting the use of intravenous lidocaine as an adjunct to propofol sedation for gastrointestinal endoscopic procedures. However, further research is necessary to optimize the use of lidocaine and fully understand its long-term effects.

A prospective-randomized placebo-controlled trial comparing the effects of nebulized dexmedetomidine v/s dexmedetomidine-lignocaine mixture on intraoperative hemodynamics and surgical field quality in patients undergoing endoscopic transnasal transsphenoidal pituitary tumor surgery

Background

During transnasal transsphenoidal pituitary surgery (TNTSS), the primary objective is to maintain stable hemodynamics while ensuring ideal surgical conditions. This study aimed to investigate the effect of nebulized dexmedetomidine on hemodynamic parameters and the quality of the surgical field during TNTSS.

Methods

Seventy-five patients scheduled for TNTSS were randomized into three groups of 25 each and received preoperative nebulization with 5 mL of nebulizing fluid consisting of 1.5 μg/kg of dexmedetomidine with saline in dexmedetomidine (D) group; 1.5 μg/kg of dexmedetomidine with 2% lignocaine in dexmedetomidine-lignocaine (DL) group and normal saline in the control (S) group. Heart rate (HR), mean blood pressure, Formmers score, anesthetic requirement, and emergence were evaluated for each group.

Results

Group S had significantly higher HR and mean arterial pressure than the other two groups across various time points during surgery (P < 0.01). The total requirements for fentanyl, propofol, sevoflurane, and labetalol and the incidence of delayed emergence were significantly higher in the S group compared to the other two groups (P < 0.01). The D and DL groups exhibited significantly better surgical field conditions than the S group. In all the parameters assessed, patients in the D group outperformed those in the DL group.

Conclusion

The administration of nebulized dexmedetomidine, both alone and in combination with lignocaine, resulted in stable hemodynamics, favorable operative conditions, reduced anesthetic requirement, and facilitated prompt emergence during TNTSS. Nebulized dexmedetomidine proved superior to its combination with lignocaine across all evaluated parameters.

Comparison of the hemodynamic effects of opioid-based versus lidocaine-based induction of anesthesia with propofol in older adults: a randomized controlled trial

BACKGROUND

The present study aims to compare the hemodynamic profile of lidocaine and fentanyl during propofol induction of general anesthesia.

METHODS

This randomized controlled trial included patients aged above 60 years undergoing elective non-cardiac surgery. The included patients received either 1 mg/kg lidocaine (n = 50) or 1 mcg/kg fentanyl (n = 50) based on total body weight with propofol induction of anesthesia. Patient's hemodynamics were recorded every minute for the first 5 min then every 2 min until 15 min after induction of anesthesia. Hypotension (mean arterial pressure [MAP] <65 mmHg or >30% reduction from baseline) was treated by intravenous 4 mcg bolus of norepinephrine. Outcomes included norepinephrine requirements (primary), the incidence of postinduction hypotension, MAP, heart rate, intubation condition, and postoperative delirium via the cognitive assessment method.

RESULTS

Forty-seven patients in the lidocaine group and 46 patients in the fentanyl group were analyzed. None in the lidocaine group experienced hypotension, while 28/46 (61%) of patients in the fentanyl group developed at least one episode of hypotension requiring a median (25th and 75th quartiles) norepinephrine dose of 4 (0,5) mcg, p-value <0.001 for both outcomes. The average MAP was lower in the fentanyl group than in the lidocaine group at all time points after anesthesia induction. The average heart rate was comparable between the two groups nearly at all time points after anesthesia induction. The overall intubation condition was comparable between the two groups. None of the included patients developed postoperative delirium.

CONCLUSION

Lidocaine-based regimen for induction of anesthesia reduced the risk of postinduction hypotension in older patients compared to the fentanyl-based regimen.

Evaluation of Propofol-Sparing Effect of Intravenous Lignocaine in Patients Undergoing Daycare Upper Gastrointestinal Endoscopic Procedures

Background Propofol is the most common sedative for endoscopies. Propofol alone may require larger doses for adequate level of sedation. Lignocaine is known for its anesthetic-sparing effect. We tested whether the addition of intravenous lignocaine to propofol-based sedation reduces its dose. Methods This prospective, randomized study was performed on 90 patients of 18 to 60 years of age, of either sex of the American Society of Anesthesiologists (ASA) Grade-I & II, and was divided into two groups. Group L + P received IV bolus of 1.5 mg/kg 2% lignocaine over 10 minutes followed by 1.5 mg/ kg/ h infusion and group NS + P- received the equivalent volumes of normal saline in bolus and infusion. Patients were induced with fentanyl (2 µg/kg) and propofol (1 mg/kg). To maintain an adequate sedation level, a supplemental bolus of 0.5 mg /kg propofol was administered. The outcomes recorded were the total and supplemental amount of propofol administered, as well as recovery time. Results The mean supplemental propofol for group L + P and group NS + P- 37.00 ± 29.93 and 58.67 ± 19.49 mg, respectively and mean total propofol consumption was 98.22 ± 34.00 mg and 131.11 ± 23.18 mg, respectively, (p < 0.001). Mean recovery time in group L + P was also shorter (5.22 ± 2.14 versus 9.96 ± 2.14). The incidence of adverse events like gag reflux, upper airway obstruction, pain on injection, and hypotension was significantly lower in group L + P (p < 0.05). Conclusion The addition of lignocaine to propofol-based sedation reduced the overall propofol requirement at the same time maintaining hemodynamic stability, spontaneous respiration, and early recovery.

Can intravenous lidocaine definitely attenuate propofol requirement and improve outcomes among colonoscopic patients under intravenous sedation?: A double-blinded, randomized controlled trial

BACKGROUND

Propofol-sparing effect of lidocaine has not been fully elucidated because propofol is usually mixed with many medications in anesthetic practice. Therefore, the study aimed to verify the additive effect of intravenous lidocaine to propofol without other sedative medications and control the depth of anesthesia using the bispectral index (BIS) during colonoscopy in a prospective, randomized, double-blinded controlled trial.

METHODS

Sixty-eight patients scheduled and undergoing colonoscopy were randomly allocated to receive intravenous lidocaine (1.5 mg/kg then 4 mg/kg/h) (Group L) or a similar volume of normal saline (Group C) with propofol administration guided by BIS monitoring. The primary outcome was total propofol requirements between group comparisons. The secondary outcomes included the number of hypoxemic periods, hemodynamic changes, duration in returning of BIS > 85, sedation scores, pain scores, postoperative opioid requirement, and patient satisfaction between group comparisons.

RESULTS

Intravenous lidocaine showed significantly reduced total propofol use (151.76 ± 50.78 mg vs 242.06 ± 50.86 mg, Group L vs Group C, respectively, P < .001). Duration in returning to BIS > 85, sedation scores, and patient satisfaction scores were significantly superior in Group L (P < .05). The number of hypoxemic episodes, changes of hemodynamic response, pain scores, and postoperative opioid requirement were similar in both groups. No adverse effects were detected in both groups.

CONCLUSION

Intravenous lidocaine produced a definitely effective reduced propofol requirement without other sedative agents and improved outcomes including patient satisfaction, duration in returning to BIS > 85, and sedation score during colonoscopy without adverse effects.

The effect of intravenous lidocaine on propofol dosage in painless bronchoscopy of patients with COPD

Background

We tested the hypothesis that intravenous (IV) lidocaine reduces propofol requirements in painless bronchoscopy in patients with chronic obstructive pulmonary disease (COPD).

Methods

A total of 93 patients who underwent bronchoscopy were included in this randomized placebo-controlled study. The patients were randomly divided into two groups. After the IV doses of nalbuphine, patients were given a bolus of propofol, which was titrated if necessary until loss of consciousness. Then patients were given IV lidocaine (2 mg/kg then 4 mg/kg/h) or the same volume of saline. The primary endpoint was the propofol requirements. Secondary endpoints were the incidence of hypoxemia, the incidence of cough during glottis examination, the systolic blood pressure (SBP) and heart rate (HR) during bronchoscopy procedures, the bronchoscopist's comforts, and the time for wakefulness before recovery.

Results

Lidocaine infusion resulted in a significant reduction in propofol requirements (p &lt; .0001), and the incidence of hypoxemia (p = .001) and cough (p = .003) during examination decreased significantly in the lidocaine group. During the examination, the fluctuation of SBP and HR was significantly lower than that in the control group, and the difference was statistically significant (p &lt; .05). Bronchoscopist's comforts were higher in the lidocaine group (p &lt; .001), and time for wakefulness (p &lt; .001) were significantly lower in the lidocaine group.

Conclusion

In painless bronchoscopy in patients with COPD, IV infusion of lidocaine resulted in a reduction in propofol dose requirements and reduce the incidence of adverse events.

Evaluation of continuous intravenous lidocaine on brain relaxation, intraoperative opioid consumption, and surgeon's satisfaction in adult patients undergoing craniotomy tumor surgery: A randomized controlled trial

BACKGROUND

In craniotomy tumor removal, brain relaxation after dura opening is essential. Lidocaine is known to have analgesic and antiinflammatory effects. It is excellent in decreasing cerebral metabolic rate of oxygen, cerebral blood flow, and cerebral blood volume; and can potentially reduce intracranial pressure, resulting in exceptional brain relaxation after dura opening. However, no study has examined continuous intravenous lidocaine infusion on brain relaxation, intraoperative opioid consumption and surgeon's satisfaction in adult patients undergoing craniotomy tumor removal.

METHODS

A total of 60 subjects scheduled for craniotomy tumor removal were enrolled in a double-blind, randomized controlled trial with consecutive sampling. Patients received either an intravenous bolus of lidocaine (2%) 1.5 mg/kg before induction followed by 2 mg/kg/h continuous infusion up to skin closure (lidocaine group) or placebo with similar volume (NaCl 0.9%). Neurosurgeons evaluated brain relaxation and surgeon's satisfaction with a 4-point scale, total intraoperative opioid consumption was recorded in μg and μg/kg/min.

RESULTS

All sixty subjects were included in the study. Lidocaine group showed better brain relaxation after dura opening (96.7% vs 70%; lidocaine vs placebo, P < .006), less intraoperative fentanyl consumption (369.2 μg vs 773.0 μg; P < .001, .0107 vs .0241 μg/kg/min; lidocaine vs placebo, P < .001). Higher surgeon's satisfaction was found in lidocaine group (96.7% vs 70%, P = .006). No side effects were observed during this study.

CONCLUSIONS

Continuous lidocaine intravenous infusion improves brain relaxation after dura opening, and decreases intraoperative opioid consumption, with good surgeon satisfaction in adult patients undergoing craniotomy tumor removal.

ED50 and ED95 of Propofol Combined with Different Doses of Intravenous Lidocaine for First-Trimester Uterine Aspiration: A Prospective Dose-Finding Study Using Up-and-Down Sequential Allocation Method

Purpose

This study aimed to test the effect of different doses of intravenous lidocaine on the median effective dose (ED50) and 95% effective dose (ED95) of propofol-induction dose and identify the optimal dose.

Patients and Methods

Patients undergoing first-trimester uterine aspiration were screened and randomly enrolled into the following groups: saline (L₀), 0.5 mg/kg lidocaine (L_0.5), 1.0 mg/kg lidocaine (L_1.0), and 1.5 mg/kg lidocaine (L_1.5). Anesthesia was induced with 1.0 µg/kg fentanyl. Prepared lidocaine or saline solution was injected later according to allocation, followed by propofol. The dose of propofol for each patient was determined using the up-and-down sequential study design. The primary end point was the ED50 and ED95 of the propofol-induction dose. The total propofol doses, awakening time, and adverse events were recorded.

Results

The ED50 (95% confidence interval) of propofol was significantly lower in groups L_1.0 and L_1.5 than group L₀ (1.6 [1.5–1.7] mg/kg and 1.8 [1.6–1.9] mg/kg, versus 2.4 [2.3–2.5] mg/kg, respectively; p<0.001). There was no significant difference in ED50 between groups L_1.0 and L_1.5 (p>0.05). However, surprisingly, the ED50 was significantly higher in group L_0.5 than L₀ (2.8 [2.6–3.0] mg/kg vs 2.4 [2.3–2.5] mg/kg; p<0.05). The total doses of propofol in groups L_1.0 and L_1.5 were lower than those in groups L₀ and L_0.5 (p<0.05). The systolic blood pressure (SBP) decline after anesthesia induction in group L_0.5 was greater than that in group L₀ (p<0.01). The incidence of respiratory depression in group L_0.5 was greater than that in groups L₀ and L_1.0 (p<0.05).

Conclusion

In patients who underwent first-trimester uterine aspiration, intravenous lidocaine 1.0 mg/kg prior to propofol injection significantly reduced the ED50 of propofol induction dose without severe side effects, equivalent to the effect of 1.5 mg/kg dose. We recommend 1.0 mg/kg as the optimal dose.

Effect of intravenous lidocaine on pain after head and neck cancer surgery (ELICO trial): A randomised controlled trial

BACKGROUND

Treatment of postoperative pain after ear, nose and throat (ENT) cancer surgery is mainly morphine administration. Additional systemic lidocaine has shown promising results in some surgical procedures.

OBJECTIVE

The main objective was to evaluate morphine consumption in the first 48 postoperative hours after intra-operative lidocaine infusion during major ENT cancer surgery.

DESIGN

A randomised, double-blind, placebo-controlled trial.

SETTING

Bicentric study including a university hospital and a major cancer centre, conducted from December 2016 to December 2019.

PATIENTS

A total of 144 patients undergoing major ENT cancer surgery were included.

INTERVENTION

The patients were randomly assigned to receive intravenous lidocaine or placebo during surgery and in the recovery room.

MAIN OUTCOME MEASURES

Endpoints were postoperative morphine consumption in the first 24 and 48 h postoperatively, intra-operative remifentanil consumption, adverse events occurrence and assessment 3 to 6 months after surgery with the McGill pain questionnaire.

RESULTS

A total of 118 patients were included (lidocaine n  = 57; placebo n  = 61, 26 patients were excluded). There was no significant difference in morphine consumption during the first 48 postoperative hours in the lidocaine group compared with the placebo group with a median [IQR] of 0.60 [0.30 to 1.03] mg kg -1 vs. 0.57 [0.37 to 0.96] mg kg -1 , total dose 44 [21 to 73.3] mg vs. 38 [23.3 to 56.5] mg, P  = 0.92.There was no significant difference between the two groups in any of the other endpoints, including at follow up 3 to 6 months after surgery.

CONCLUSION

Intravenous lidocaine in ENT cancer surgery did not show any additional analgesic or morphine-sparing effect 48 h after surgery. Three to six months after surgery, there was no significant difference in pain scores or consumption of analgesics. Patients treated pre-operatively with opioids were not evaluated in the study.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT02894710 and EUDRACT number 2015-005799-90.

Intravenous Lidocaine Significantly Reduces the Propofol Dose in Elderly Patients Undergoing Gastroscopy: A Randomized Controlled Trial

Objective

Propofol-based sedation has been widely used for gastroscopy, but the risk of respiratory suppression in elderly patients should not be overlooked. Intravenous (IV) lidocaine during surgery can reduce the demand for propofol and the incidence of cardiopulmonary complications. We examined whether IV lidocaine reduces the dose of propofol and the occurrence of adverse events during gastroscopy in elderly patients.

Methods

We conducted a prospective, single-center, double-blind randomized controlled trial in elderly patients aged ≥65 years with ASA I-II. Subjects were randomly assigned to the lidocaine group (Group L, n=70), who received IV 1.5 mg kg⁻¹ lidocaine followed by a continuous infusion of 4 mg kg⁻¹ h⁻¹ lidocaine, or the normal saline group (Group N, n=70), who received an equal volume of saline in the same way.

Results

IV lidocaine reduced the total and maintenance propofol dose in Group L (p<0.001), with no significant effect on the induction dose. The incidence of intraoperative hypoxia (p=0.035), emergency airway management events (p=0.005), duration of gastroscopy (p<0.05), consciousness recovery time (p<0.001), and postoperative pain (p=0.009) were all reduced in Group L. Patient (p=0.025) and gastroscopist (p=0.031) satisfaction was higher in Group L. Intraoperative hemodynamic parameters, the respiratory rate, the incidence of sedation-related events and anesthesiologist satisfaction were similar between the two groups.

Conclusion

IV lidocaine can significantly reduce the amount of propofol, the incidence of hypoxia and postoperative pain during gastroscopy in elderly patients, with a higher patient and gastroscopist satisfaction.

Effect of intravenous lidocaine on propofol consumption in elderly patients undergoing colonoscopy: a double-blinded, randomized, controlled trial

BACKGROUND

Elderly patients undergoing colonoscopy with propofol as sedation are prone to respiratory or cardiovascular complications. Intravenous lidocaine has analgesic efficacy and reduces propofol consumption during surgery. Here, the effect of intravenous lidocaine on propofol consumption was evaluated in elderly patients undergoing colonoscopy.

METHODS

Patients were randomly allocated to receive intravenous lidocaine (1.5 mg/kg bolus dose, followed by a 2 mg/kg/h continuous infusion during the procedure; Group L) or a placebo (saline; Group N). During the procedure, sedation was achieved by propofol. The following outcomes were recorded: total propofol consumption; time to loss of consciousness; number of airway modifications; time to the first airway intervention; incidence of sedation-related events; pain score after awakening; endoscopists' and patients' satisfaction scores; memory level of the procedure; and adverse events within 24 h postoperatively.

RESULTS

Compared with Group N, propofol consumption was reduced by 13.2% in Group L (100.30 ± 25.29 mg vs. 115.58 ± 27.52 mg, respectively, p = 0.008). Kaplan-Meier curves showed that the median time to the loss of consciousness episode was shorter in Group L than in Group N (40 s vs. 55 s, respectively, log rank p < 0.0001). The number of airway modifications, time to the first airway intervention, incidence of sedation-related events, time to awakening, pain score after awakening, endoscopists' and patients' satisfaction scores, memory level of the procedure and adverse events within 24 h postoperatively did not differ between the two groups (p > 0.05).

CONCLUSIONS

Intravenous lidocaine can reduce propofol consumption in elderly patients undergoing colonoscopy, with quicker time to loss of consciousness.

TRIAL REGISTRATION

The clinical trial was registered at (12/01/2021, ChiCTR2100042001 ).

The effects of target-controlled infusion of lidocaine undergoing vocal cord polypectomy: A randomized controlled trial (CONSORT compliant)

BACKGROUND

The present study aimed to assess the efficacy and safety of general anesthesia-assisted target-controlled plasma infusion of lidocaine in patients with vocal cord polypectomy using a supporting laryngoscope.

METHODS

In total, 80 patients undergoing vocal cord polypectomy using a supporting laryngoscope were randomly divided into an intervention group and a control group; each group contained 40 subjects: both groups received general anesthesia; subjects in the intervention also received an additional 3 mg/L of lidocaine by target-controlled plasma infusion during induction and maintenance of anesthesia; heart rate (HR) mean arterial pressure (MAP), propofol and urapidil consumption (Uradil, which is a blood pressure drug that blocks alpha-1, is called Urapidi Hydrochloride Injection. It is produced by Germany, the enterprise name is Nycomed Deutschland GmbH, the import drug registration number is H20090715, and it is widely used in China), recovery time, and cough score (measured by Minogue et al's 5-grade scoring method) during extubation, and throat pain score (measured by visual analogue scale,[VAS]) after extubation and adverse events were recorded.

RESULTS

Significant differences were observed in HR (P < .05) and MAP (P < .05) immediately after intubation (T2), immediately after the operation starting to support laryngoscope exposure (T3), immediately after operation field adrenergic tampon hemostasis (T4), and 5 minutes after hemostasis (T5) between the 2 groups, and significant differences were also observed in HR (P < .05) before intubation (T1). Moreover, significant differences were observed in propofol consumption (P < .05), urapidil consumption (P < .05), cough score during extubation (P < .05), and throat pain score after extubation (P < .05). However, no significant difference was observed in the recovery time (P > .05). Furthermore, no adverse events were detected in either group.

CONCLUSION

The results of this study showed that target-controlled plasma infusion of lidocaine can reduce propofol consumption in patients undergoing vocal cord polypectomy by supporting laryngoscopy, and the hemodynamics are more stable and reduce the coughing reaction in the wake period and throat pain after extubation without adverse events.

Clinical Efficacy of Perioperative Intravenous Dexmedetomidine and Lidocaine Combined Infusion for Thyroidectomy: A Prospective, Randomized, Double-Blind, Placebo-Controlled Trial

OBJECTIVES

The aim of this study was to evaluate the efficacy of perioperative dexmedetomidine (DEX) combined with lidocaine intravenous infusion on relieving postoperative pain and improving recovery for patients undergoing thyroidectomy.

MATERIALS AND METHODS

A total of 138 patients undergoing thyroidectomy with general anesthesia were randomly divided into 4 groups: lidocaine (1.5 mg/kg bolus followed by 2 mg/kg/h infusion) in the group L, DEX (0.5 µg/kg) in the group D, lidocaine (same as the group L) with DEX (0.5 µg/kg) in the group L+D, and placebo as normal saline in the group C. All drugs were infused until the end of the surgery. The visual analog scale (VAS) scores of patients at 1, 4, 8, 12, and 24 hours following surgery, opioid requirement, propofol consumption, incidence of postoperative nausea and vomiting, awaking time, hemodynamic variables, and any adverse effects were assessed.

RESULTS

Compared with the group C, the VAS scores in the group L+D were significantly lower until 8 hours after surgery (P<0.05), while the VAS scores were significantly decreased just until 4 hours in the group L and 1 hour in the group D after surgery (P<0.05). There was no significant difference in opioid consumption between 4 groups. Propofol consumption in the group L+D was significantly lower than other groups (P<0.05). Compared with the group C, the incidence of postoperative nausea and vomiting in the group L+D was lower (P<0.05), and awaking time in the group L+D and the group L was shorter (P<0.05).

CONCLUSION

DEX combined with lidocaine infusion can effectively attenuate the postoperative pain without any serious adverse events, which may improve postoperative recovery in patients undergoing thyroidectomy.

Evaluation of lignocaine, dexmedetomidine, lignocaine-dexmedetomidine infusion on pain and quality of recovery for robotic abdominal hysterectomy: a prospective randomized controlled trial

Background: Acute postoperative pain is associated with poor quality of recovery after surgery. Perioperative use of intravenous lignocaine or dexmedetomidine have demonstrated better pain control, early return of bowel function, and effects on quality of recovery.

Methods: Ninety-six women planned for elective robotic abdominal hysterectomy were randomized into four groups. Groups received lignocaine infusion (1.5 mg.kg⁻¹ loading, 2 mg.kg⁻¹.h⁻¹ infusion) (Group I), dexmedetomidine infusion (1 µg.kg⁻¹ loading, 0.6 µg.kg⁻¹.h⁻¹ infusion) (Group 2), lidocaine (1.5 mg.kg⁻¹ loading, 2 mg.kg⁻¹.h⁻¹ infusion), and dexmedetomidine infusions (1 µg.kg⁻¹ loading, 0.5 µg.kg⁻¹.h⁻¹ infusion) (Group 3), and normal saline 10 mL loading, 1 mL.kg⁻¹.h⁻¹ infusion) (Group 4). Primary outcome was visual analogue pain scores at 1, 2, 4, 12, and 24 hours after surgery. Secondary outcomes included postoperative fentanyl requirement, time of return of bowel sounds and flatus, QoR15 score on day 1, 2, and discharge.

Results: The VAS was significantly lower in Groups 2 and 3 compared to Groups 1 and 4. Total postoperative fentanyl consumption in the first 24 hours was 256.25 ± 16.36 mcg (Group 1), 177.71 ± 16.81 mcg (Group 2), 114.17 ± 16.19 mcg (Group 3), and 304.42 ± 31.26 mcg (Group 4), respectively. Time to return of bowel sounds and passage of flatus was significantly shorter in Groups 2 and 3 (p < 0.01). QoR15 scores after surgery were higher in Group 3 compared to Groups 1, 2, and 4, (p < 0.01) respectively.

Conclusion: Combined infusion of lignocaine and dexmedetomidine significantly decreased postoperative pain, fentanyl consumption, and improved quality of recovery score after surgery in patients undergoing Robotic abdominal hysterectomy.

Perioperative Intravenous Lidocaine Infusion on Postoperative Recovery in Patients Undergoing Arthroscopic Rotator Cuff Repair Under General Anesthesia - A Randomized Controlled Trial

OBJECTIVE

Arthroscopic rotator cuff repair (ARCR) is known to cause severe postoperative pain which may interfere with recovery. Intravenous (IV) lidocaine has analgesic, anti-inflammatory, and anti-hyperalgesic effects, and is being used in various types of surgeries. However, the effect of IV lidocaine in ARCR is not well known.

MATERIALS AND METHODS

Ninety patients undergoing ARCR were randomly allocated to receive IV lidocaine (1.5▒mg/kg bolus of 1% lidocaine after anesthesia induction followed by a continuous infusion of 2▒mg/kg/h up to 1▒h after surgery) or an equal volume of saline. In both groups, an IV patient-controlled analgesia (PCA) device was used which contained fentanyl 10▒µg/mL, infused at 1▒mL/h with a 1▒mL bolus dose. The primary outcome was fentanyl requirements given via IV PCA during the first 24 hours after surgery. Perioperative pain scores and functional recovery were assessed as secondary outcomes.

RESULTS

The amount of fentanyl administered via IV PCA up to 24 hours after surgery was significantly lower in the Lidocaine group compared to the Control group (329 [256.2-428.3] vs. 394.5 [287.0-473.0], P=0.037) The number of PCA bolus attempts were lower in the Lidocaine group without statistical significance. There were no differences in postoperative pain scores or functional shoulder scores between the two groups.

DISCUSSION

IV lidocaine appears to be helpful in reducing opioid requirements during the acute postoperative period in patients undergoing ARCR. IV lidocaine may be a viable option as a component of multimodal analgesia in ARCR when regional analgesia is not possible.

Efficacy and safety of supplemental intravenous lidocaine for sedation in gastrointestinal endoscopic procedures: systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND AIMS

Some studies have shown that intravenous (IV) lidocaine reduces the dose requirement of propofol in GI endoscopic procedures. We conducted this study to evaluate the efficacy and safety of the combination of IV lidocaine and propofol compared with propofol alone in GI endoscopic procedures.

METHODS

We reviewed several databases from inception to October 13, 2020, to identify randomized controlled trials (RCTs) that compared the role of IV propofol and lidocaine with IV propofol plus placebo for sedation in endoscopic procedures. Our outcomes of interest were the differences in total dose of propofol administered, procedure time, and intraoperative adverse events. For categorical variables, we calculated pooled risk ratios with 95% confidence intervals (CI); for continuous variables, we calculated standardized mean difference (SMD) with 95% CI. Data were analyzed using a random effect model. We used the GRADE (Grading of Recommendations Assessment, Development and Evaluation) framework to ascertain the quality of evidence.

RESULTS

We included 5 randomized controlled trials with 318 patients. We found that the total dose of propofol administered was significantly lower in the lidocaine group than the control group (SMD, -0.76; 95% CI, -1.09 to -0.42). We found no significant difference in procedure time (SMD, 0.16; 95% CI, -0.26 to 0.57) or adverse events (risk ratio, 0.60; 95% CI, 0.35-1.03) between the groups. There was moderate to substantial heterogeneity in the data. Quality of evidence based on the GRADE framework ranged from low to moderate.

CONCLUSIONS

Moderate quality of evidence suggests that IV lidocaine decreases the dose of propofol administered for GI endoscopic procedures.

Pre-procedure intravenous lidocaine administration on propofol consumption for endoscopic retrograde cholangiopancreatography: A prospective, randomized, double-blind study

BACKGROUND AND AIM

The endoscopic retrograde cholangiopancreatography (ERCP) procedure is generally performed in patients with high comorbidity. We aimed to reduce the consumption of propofol by adding lidocaine before ERCP.

METHODS

Eighty ERCP patients with ASA I-III, aged between 45-75 years, were randomly divided into two groups. Lidocaine group (group L, n = 40), received 1-mg midazolam, 1.5 mg/kg lidocaine, and 1 mg/kg propofol intravenously. The control group (group C, n = 40) received 1-mg midazolam, saline in the same volume as the lidocaine group, and 1 mg/kg propofol intravenously. Propofol was administered with intermittent bolus doses. Propofol consumption, oropharyngeal reflex, recovery time, endoscopist satisfaction, ketamine need, and side-effects were recorded.

RESULTS

Propofol consumption during the procedure was statistically lower in group L than in the control group (157.25 ± 39.16 mg vs 228.75 ± 64.62 mg respectively, P < 0.001). Additionally, recovery time was statistically faster in group L compared with the control group (7.78 ± 3.95 min vs 11.92 ± 3.24 min respectively, P < 0.001). The oropharyngeal reflex was less in group L than control group (6/40 vs 15/40 respectively, P = 0.042). There was no significant difference between the two groups regarding visual analogue scale scores and endoscopist satisfaction (P > 0.05).

CONCLUSIONS

We recommend the use of intravenous lidocaine before the ERCP procedure as it reduces propofol consumption, recovery times, and oropharyngeal reflex.

The benefit of adding lidocaine to ketamine during rapid sequence endotracheal intubation in patients with septic shock: A randomised controlled trial

BACKGROUND

Patients with septic shock commonly require endotracheal intubation under general anaesthesia in the operating theatre, the emergency department, and the intensive care unit. Hypotension is a serious complication after induction of general anaesthesia, especially in patients with circulatory failure. No randomised controlled trials had previously investigated protocols for induction of anaesthesia in septic shock patients. The aim of the current work is to compare two protocols, lidocaine-ketamine combination versus ketamine full-dose for rapid-sequence endotracheal intubation in patients with septic shock.

METHODS

Forty-four adult patients, with septic shock, scheduled for emergency surgical intervention were enrolled in this randomised, double-blinded, controlled study. Patients were randomised to receive either 1 mg/kg ketamine (ketamine group, n = 22) or 0.5 mg/kg ketamine plus 1 mg/kg lidocaine (ketamine-lidocaine group, n = 22) for induction of anaesthesia in addition to 0.05 mg/kg midazolam (in both groups). Our primary outcome was the mean arterial pressure (MAP). Other outcomes included frequency of post-induction hypotension, heart rate, and cardiac output.

RESULTS

Forty-three patients were available for final analysis. The average MAP reading in the first 5 min post-induction was higher in ketamine-lidocaine group than in the ketamine group {82.8 ± 5.6 mmHg and 73 ± 10.2 mmHg, P < 0.001}. Furthermore, the incidence of post-intubation hypotension was lower in the ketamine-lidocaine group than in the ketamine group {1 patient (5%) versus 17 patients (77%), P < 0.001}. The ketamine-lidocaine group showed higher MAP in almost all the readings after induction compared to ketamine group. Other haemodynamic variables including cardiac output and heart rate were comparable between both study groups.

CONCLUSION

Lidocaine-ketamine combination showed less incidence of hypotension compared to ketamine full-dose when used for rapid-sequence endotracheal intubation in patients with septic shock. REGISTRATION URL: https://clinicaltrials.gov/ct2/show/NCT03844984?cond=NCT03844984&rank=1.

Application of Intravenous Lidocaine in Obese Patients Undergoing Painless Colonoscopy: A Prospective, Randomized, Double-Blind, Controlled Study

OBJECTIVE

Propofol for procedural sedation and analgesia (PSA) for colonoscopy can result in a high prevalence of severe respiratory depression. Studies have shown that intravenous (IV) infusion of lidocaine can reduce propofol requirements significantly and increase the ventilatory response to carbon dioxide in humans. We tested the hypothesis that IV lidocaine could improve propofol-induced respiratory depression in obese patients during colonoscopy.

METHODS

Ninety obese patients scheduled for painless colonoscopy were randomized to receive lidocaine (1.5 mg/kg, then 2 mg/kg/h, IV) or the same volume of 0.9% saline. Intraoperative sedation was provided by propofol. The primary outcome was the number of oxygen-desaturation episodes. Secondary outcomes were: the number of apnea episodes; total propofol consumption; time to the first hypoxia episode; time to consciousness loss; intraoperative hemodynamic parameters; awakening time; adverse events; duration of post-anesthesia care unit (PACU) stay; satisfaction of endoscopists and patients.

RESULTS

Demographic characteristics between the two groups were comparable. The number of oxygen-desaturation episodes in group L (1.49±1.12) decreased by 0.622 (P=0.018) compared with that in group N (2.11±1.32), and the number of apnea episodes in group L decreased by 0.533 (P<0.001). Kaplan-Meier curves showed that the median time to the first hypoxia episode was longer in group L (86.78 s) than that in group N (63.83 s) (Log rank P=0.0008). The total propofol consumption, awakening time, and duration of PACU stay were reduced in group L. There was no significant difference in the prevalence of adverse events (P>0.05 for all). Satisfaction scores for endoscopists and patients in group L were higher than that in group N (P<0.001).

CONCLUSION

Intravenous infusion of lidocaine could significantly reduce the number of oxygen-desaturation and apnea episodes in obese patients during painless colonoscopy. This method is worthy of clinical promotion.

CLINICAL TRIALS REGISTRATION

ChiCTR2000028937.

Efficacy and safety of intravenous lidocaine in propofol-based sedation for ERCP procedures: a prospective, randomized, double-blinded, controlled trial

BACKGROUND AND AIMS

Propofol-based sedation is widely used in ERCP procedures, but adverse respiratory or cardiovascular events commonly occur. Intravenous injection of lidocaine has an analgesic effect and can reduce the requirements of fentanyl and propofol during abdominal surgery. The objective of this study was to assess the efficacy and safety of intravenous lidocaine on propofol requirements during ERCP procedures.

METHODS

Forty-eight patients scheduled for ERCP were randomly divided into 2 groups, the lidocaine group and the control group. All patients received .02 mg/kg midazolam and .1 μg/kg sufentanil intravenously as premedication. A bolus of propofol was applied for induction of sedation, and perfusion of propofol was applied for maintenance. Patients in the lidocaine group received a bolus of 1.5 mg/kg lidocaine intravenously followed by continuous infusion of 2 mg/kg/h, whereas the control group received the same volumes of saline solution. The primary outcome was the propofol requirement during ERCP.

RESULTS

Compared with the control group, propofol requirements were reduced by 33.8% in the lidocaine group (212.0 ± 118.2 mg vs 320.0 ± 189.6 mg, P = .023). Involuntary movement was less common in the lidocaine group than in the control group (12.5% vs 41.7%, P = .049). In the lidocaine group, postprocedure pain and fatigue, as measured by the visual analog scale, were significantly reduced (0 [range, 0-4] vs 3 [range, 0-5], P = .005; 2 [range, 0-4] vs 5 [range, 2-8], P < .001).The incidence of oxygen desaturation, hypotension, and bradycardia tended to be lower in the lidocaine group.

CONCLUSIONS

Intravenous lidocaine can significantly decrease propofol requirements during ERCP, with higher sedation quality and endoscopist satisfaction. (Clinical trial registration number: NCT03996577.).

Effect of intravenous lignocaine infusion on the quality of emergence in patients undergoing transsphenoidal resection of pituitary tumors - A prospective, randomized controlled trial

Background:

Emergence from anesthesia is a critical step in patients undergoing transsphenoidal pituitary surgery (TSS). The cough suppressant and anesthetic sparing properties of lignocaine makes it a favorable option for smooth extubation and maintaining stable hemodynamics intraoperatively. We aimed to evaluate the effect of lignocaine infusion on the quality of emergence (QOE) and intraoperative hemodynamics in patients undergoing transsphenoidal resection of pituitary tumors.

Methods:

Fifty patients scheduled to undergo TSS were randomly divided into ligocaine group (n = 25), receiving 1.5 mg/kg bolus dose of lignocaine followed by continuous infusion of 1.5 mg/kg/h and saline group (n = 25). Patients assigned to the control group received equal volume of saline receiving equal volume of saline. The four emergence parameters (mean arterial pressure [MAP], heart rate (HR), cough, and agitation) were abbreviated into an aggregated score for QOE. Time to emergence and intraoperative hemodynamics were also recorded.

Results:

The QOE was not found to be different between the two groups (P = 0.294). Lignocaine did not increase the time to emergence (P = 0.166). The intraoperative HR and MAP were comparable between the two groups. A lower minimum alveolar concentration of desflurane was required in lignocaine group during insertion of nasal speculum (P = 0.018) and at the time of seller ridge dissection (P = 0.043) compared to the saline group.

Conclusion:

Intraoperative lignocaine infusion of 1.5 mg/kg/h did not significantly improve the QOE with respect to hemodynamics, cough, and emergence agitation in patients undergoing transsphenoidal resection of pituitary tumors.

The propofol-sparing effect of intravenous lidocaine in elderly patients undergoing colonoscopy: a randomized, double-blinded, controlled study

Background

Propofol provides a prominent sedation effect in colonoscopy. However, anesthesia and sedation induced with propofol in the elderly might result in cardiopulmonary complications, especially when it is combined with opoids in the regimen. This study aimed to test the hypothesis that the addition of intravenous lidocaine to propofol-based sedation could decrease the overall propofol requirement in elderly patients during colonoscopy while the procedural sedation satisfaction and the hemodynamic stability were not compromised.

Methods

Ninety-two patients undergoing colonoscopy were randomly enrolled into lidocaine+propofol (L + P) group or normal saline+propofol (NS + P) groups. Subjects received intravenous bolus of 1.5 mg/kg lidocaine followed by 4 mg kg^− 1 h^− 1 lidocaine continuous infusion in L + P group or equivalent volumes of normal saline for boluses and infusion in NS + P group. Anesthesia was induced with 2.5 μg sufentanil followed by injection of 1.2 mg kg^− 1 propofol in all patients. A single supplemental bolus of 0.6 mg kg^− 1 propofol was administered whenever MOAA/S score > 1 or had body movement during the colonoscopy. The recorded primary endpoints included: the total amount of propofol administered during entire procedure, the supplemental amount of propofol after induction, and the frequencies of boluses of supplemental propofol.

Results

A total of 79 patients were included in the final analysis. Compared with NS + P group, the total amounts of propofol (induction plus supplemental) were no significant differences in L + P group; however, the required supplemental propofol was less (69.9 ± 39.2 mg vs. 51.5 ± 38.6 mg) (P = 0.039); the average frequencies of boluses of supplemental propofol given after induction were lower (2.1 ± 1.1 vs. 1.4 ± 0.9) (P = 0.003); the calculated “unit propofol” infusion rate was lower (0.18 ± 0.05 vs. 0.14 ± 0.04 mg kg^− 1 min^− 1) (P = 0.002).

Conclusions

The addition of intravenous lidocaine to propofol-based sedation resulted in a remarked reduction of supplemental propofol in the elderly during colonoscopy.

Trial registration

The present clinical trial was registered at http://www.chictr.org.cn on 11th March 2019 (registration No. ChiCTR1900021818).

Effect of Intravenous Lidocaine Infusion on Postoperative Early Recovery Quality in Upper Airway Surgery

OBJECTIVES/HYPOTHESIS

Systemic infusions of lidocaine have been widely used as perioperative analgesic adjuvants. The aim of this randomized, double-blinded, controlled trial was to investigate the effect of perioperative lidocaine infusion on postoperative early recovery quality in upper airway surgery.

STUDY DESIGN

Prospective, randomized, double-blinded, placebo-controlled trial.

METHODS

A total of 99 patients were randomly assigned to the lidocaine group (group L) or the control group (group C). The patients received 2 mg/kg lidocaine completed within 10 minutes before the induction of anesthesia followed by continuous infusions of 2 mg/kg/hr lidocaine (group L) or the same volume of 0.9% normal saline (group C) intravenously during anesthesia. The Quality of Recovery-40 (QoR-40) survey was administered on the preoperative day (Pre) and postoperative days 1 (POD1) and 2 (POD2). The primary endpoint was QoR-40 score on POD1 and POD2.

RESULTS

Compared with Pre, global QoR-40 scores on POD1 and POD2 were significantly lower (P < .05). Compared with group C, global QoR-40 scores were significantly higher in group L on POD1 and POD2 (P < .05). Among the five dimensions of QoR-40, the scores for physical comfort, emotional state, and pain were superior in group L compared to group C (P < .05). Compared with group C, the consumption of remifentanil and diclofenac as well as the incidence of postoperative nausea and vomiting (PONV) and postoperative 48-hour numeric rating scale (NRS) scores in group L were significantly lower (P < .05).

CONCLUSIONS

Systemic lidocaine infusion can improve QoR-40 scores in patients with upper airway surgery, reduce the dosage of intraoperative opioids, decrease the incidence of PONV and NRS scores 2 days after surgery, thus improving postoperative early recovery quality.

LEVEL OF EVIDENCE

1b Laryngoscope, 131:E63-E69, 2021.

Intravenous lidocaine as adjuvant to general anesthesia in renal surgery

The role of intraoperative intravenous lidocaine infusion has been previously evaluated for pain relief, inflammatory response, and post-operative recovery, particularly in abdominal surgery. The present study is a randomized double-blinded trial in which we evaluated whether IV lidocaine infusion reduces isoflurane requirement, intraoperative remifentanil consumption and time to post-operative recovery in non-laparoscopic renal surgery. Sixty patients scheduled to undergo elective non-laparoscopic renal surgery under general anesthesia were enrolled to receive either systemic lidocaine infusion (group L: bolus 1.5 mg/kg followed by a continuous infusion at the rate of 2 mg/kg/hr until skin closure) or normal saline (0.9% NaCl solution) (Group C). The depth of anesthesia was monitored using the Bispectral Index Scale (BIS), which is based on measurement of the patient’s cerebral electrical activity. Primary outcome of the study was End-tidal of isoflurane concentration (Et-Iso) at BIS values of 40–60. Secondary outcomes include remifentanil consumption during the operation and time to extubation. Et-Iso was significantly lower in group L than in group C (0.63% ± 0.10% vs 0.92% ± 0.11%, p < 10^–3). Mean remifentanil consumption of was significantly lower in group L than in group C (0.13 ± 0.04 µg/kg/min vs 0.18 ± 0.04 µg/kg/min, p < 10^–3). Thus, IV lidocaine infusion permits a reduction of 31% in isoflurane concentration requirement and 27% in the intraoperative remifentanil need. In addition, recovery from anesthesia and extubation time was shorter in group L (5.8 ± 1.8 min vs 7.9 ± 2.0 min, p < 10^–3). By reducing significantly isoflurane and remifentanil requirements during renal surgery, intravenous lidocaine could provide effective strategy to limit volatile agent and intraoperative opioids consumption especially in low and middle income countries.

The minimum infusion rate of alfaxalone during its co-administration with lidocaine at three different doses by constant rate infusion in goats

OBJECTIVE

To determine the minimum infusion rate (MIR) of alfaxalone required to prevent purposeful movement in response to standardized stimulation while co-administered with lidocaine at three different doses by constant infusion rate infusion (CRI) in goats.

STUDY DESIGN

Prospective, blinded, randomized crossover, experimental.

ANIMALS

A total of eight healthy goats: four does and four wethers.

METHODS

Anaesthetic induction was with lidocaine at 1 mg kg^-1 [low dose of lidocaine (L-Lid)], 2 mg kg^-1 [moderate dose (M-Lid)] or 4 mg kg^-1 [high dose (H-Lid)] and alfaxalone at 2 mg kg^-1. Anaesthetic maintenance was with alfaxalone initially at 9.6 mg kg^-1 hour^-1 combined with one of three lidocaine treatments: 3 mg kg^-1 hour^-1 (L-Lid), 6 mg kg^-1 hour^-1 (M-Lid) or 12 mg kg^-1 hour^-1 (H-Lid). The MIR of alfaxalone was determined by testing for responses to a stimulation in the form of clamping on a digit with a Vulsellum forceps every 30 minutes during lidocaine CRI. Basic cardiopulmonary parameters were measured.

RESULTS

The alfaxalone MIRs were 8.64 (6.72-10.56), 6.72 (6.72-8.64) and 6.72 (6.72-6.72) mg kg^-1 hour^-1 during L-Lid, M-Lid and H-Lid, respectively, without any significant differences among treatments. Compared to the initial rate of 9.6 mg kg^-1 hour^-1, these reductions in MIR are equivalent to 10, 30 and 30%, respectively. Significant increases in heart rate (HR) and arterial carbon dioxide partial pressure (PaCO₂) and decreases in arterial haemoglobin saturation (SaO₂), arterial oxygen partial pressure (PaO₂) and respiratory frequency (f_R) immediately after induction were observed during all lidocaine treatments.

CONCLUSIONS AND CLINICAL RELEVANCE

Lidocaine reduces the alfaxalone MIR by up to 30% with a tendency towards a plateauing in this effect at high CRIs. Immediate oxygen supplementation might be required to prevent hypoxaemia.

The effects of intravenous lignocaine on depth of anaesthesia and intraoperative haemodynamics during open radical prostatectomy

Background

Lignocaine is a local anaesthetic agent, which is also commonly used as a perioperative analgesic adjunct to accelerate rehabilitation and enhance recovery after surgery. Lignocaine’s systemic effects on intraoperative haemodynamics and volatile anaesthetic requirements are not well explored. Therefore, we evaluated the effects of intravenous lignocaine on intraoperative volatile agent requirements and haemodynamics in patients undergoing major abdominal surgery.

Methods

We performed an analysis of 76 participants who underwent elective open radical retropubic prostatectomy. Patients received lignocaine (1.5 mg/kg loading dose) followed by an infusion (1.5 mg/kg/h) for the duration of surgery, or saline at an equivalent rate. The aims of the study were to evaluate the end-tidal sevoflurane concentration required to maintain a bispectral index of between 40 and 60. Measurements included intraoperative blood pressure, heart rate, and the volume of intravenous fluids and dosage of vasoactive medications administered.

Results

The average end-tidal sevoflurane concentration was lower in the Lignocaine group compared to saline [1.49% (SD: 0.32) vs. 1.89% (SD: 0.29); 95% CI 0.26–0.5, p < 0.001]. In the Lignocaine group, the average mean arterial pressure was 80.3 mmHg (SD: 4.9) compared to 85.1 mmHg (SD: 5.4) in the Saline group (95% CI 2.4–7.1, p < 0.001). Systolic blood pressure was also lower in the Lignocaine group: 121.7 mmHg (SD: 6.1) vs. 128.0 mmHg (SD: 6.4) in the Saline group; 95% CI 3.5–9.2, p < 0.001, as was the mean heart rate [Lignocaine group: 74.9 beats/min (SD: 1.8) vs. 81.5 beats/min (SD: 1.7) in the Saline group, 95% CI 4.1–9.1, p < 0.001]. Maintenance fluid requirements were higher in the Lignocaine group: 3281.1 mL (SD: 1094.6) vs. 2552.6 mL (SD: 1173.5) in the Saline group, 95% CI 206–1251, p = 0.007. There were no differences in the use of vasoactive drugs.

Conclusions

Intravenous lignocaine reduces volatile anaesthetic requirements and lowers blood pressure and heart rate in patients undergoing open radical prostatectomy.

Lidocaine as an Induction Agent for Intracranial Aneurysm Surgery: A Case Series

Introduction:

Induction of anaesthesia and its associated spikes in blood pressure can cause rupture of an aneurysm during intracranial surgery. Lidocaine can reportedly provide hemodynamic stability when applied before endotracheal intubation. Rapid injection of large doses of lidocaine can cause unconsciousness.

Case Presentation:

Lidocaine was applied as the sole anaesthetic for induction and maintenance during aneurysm surgery in four patients undergoing intracranial aneurysm surgery. Blood pressure alteration after induction and during surgery, bleeding, brain laxity, intracranial pressure and extubation time were acceptable.

Conclusions:

Although propofol remains a standard agent for such types of surgeries, lidocaine proved equally effective and coupled with its low cost, minimal side effects and omission of other hypnotic agents was a plausible induction agent and a maintenance drug in the selected cases.

Endotracheal intubation without muscle relaxants in children using remifentanil and propofol: Comparative study

Introduction:

Endotracheal intubation is essential during general anesthesia and muscle relaxant drugs provide ideal conditions for this purpose. The objective of this study was to evaluate the intubating condition of remifentanil combined with propofol without muscle relaxant.

Materials and Methods:

In this prospective randomized study, 60 children aged 3-12 years, American Society of Anesthesiologists physical status I and II were included. All the children were premedicated with 0.05 mg/kg midazolam and 1.5 mg/kg lidocaine 5 min before the induction of anesthesia with 3 mg/kg propofol. Then, they were allocated randomly to receive either 2 μg/kg remifentanil (group R) or 1.5 mg/kg succinylcholine (group S). Tracheal intubation was attempted 90 s after the administration of propofol. The quality of intubation was assessed by using Copenhagen score based on jaw relaxation, ease of laryngoscopy, position of vocal cord, coughing and limb movement. Heart rate and blood pressure were recorded before and after induction, and 1, 3, 5 min after intubation.

Results:

There was no significant difference in intubating condition between the two groups (P = 0.11). Intubation condition was excellent in 26 of 30 (86.7%) patients in the group R compared with 30 (100%) patients in the group S. We observed significant difference in heart rate and systolic blood pressure over time between two groups (P = 0.02, P = 0.03 respectively). After intubation, we had higher heart rate and systolic blood pressure with a significant difference in group S compared with group R (P = 0.006, P = 0.018). None of the children had a chest rigidity, laryngospasm, and hypoxia.

Conclusions:

In premedicated children, propofol-remifentanil combination provides adequate conditions for tracheal intubation that is comparable with succinylcholine. Hemodynamic response to laryngoscopy and tracheal intubation was controlled better in group R.

Required propofol dose for anesthesia and time to emerge are affected by the use of antiepileptics: prospective cohort study

Background

We investigated the impact of the type of neurological disorder on the required propofol dose for anesthesia and the time to emerge from anesthesia during dental treatment in patients with autism (AU), cerebral palsy (CP), and intellectual disability (ID), some of whom also had epilepsy.

Methods

We studied 224 patients with a neurological disorder who underwent dental treatment under intravenous general anesthesia. Patients were categorized according to neurological disorder (AU, CP, and ID; and with or without an antiepileptic). The propofol dose required for anesthesia, time to emerge, and modeled propofol blood concentration at emergence were evaluated.

Results

In patients not given an antiepileptic, we found no significant differences in the propofol dose, modeled propofol blood concentration at emergence, or time to emerge among patients with AU, CP, and ID (P > 0.05). When using an antiepileptic, the dose of propofol (5.7 ± 1.51 mg/kg/h) was significantly lower than without an antiepileptic (6.8 ± 1.27 mg/kg/h) (P < 0.0001). The modeled propofol blood concentration at emergence in patients given an antiepileptic (0.5 ± 0.03 μg/ml) was significantly lower than without an antiepileptic (0.7 ± 0.02 μg/ml) (P < 0.0001). The time to emerge in patients given an antiepileptic (29.5 ± 12.5 min) was significantly longer than without an antiepileptic (21.6 min ± 10.0 min) (P < 0.0001).

Conclusion

The propofol dose required for anesthesia and the time to emerge from anesthesia are not affected by the type of neurological disorder, but are affected by antiepileptic use.

Trial registration

University Hospital Medical Information Network Clinical Trials Registry (UMIN000014179), Date of registration 4 June 2014.

The thermodynamics of general and local anesthesia

General anesthetics are known to cause depression of the freezing point of transitions in biomembranes. This is a consequence of ideal mixing of the anesthetic drugs in the membrane fluid phase and exclusion from the solid phase. Such a generic law provides physical justification of the famous Meyer-Overton rule. We show here that general anesthetics, barbiturates, and local anesthetics all display the same effect on melting transitions. Their effect is reversed by hydrostatic pressure. Thus, the thermodynamic behavior of local anesthetics is very similar to that of general anesthetics. We present a detailed thermodynamic analysis of heat capacity profiles of membranes in the presence of anesthetics. Using this analysis, we are able to describe experimentally observed calorimetric profiles and predict the anesthetic features of arbitrary molecules. In addition, we discuss the thermodynamic origin of the cutoff effect of long-chain alcohols and the additivity of the effect of general and local anesthetics.

Comparison of the potency of different propofol formulations: a randomized, double-blind trial using closed-loop administration

BACKGROUND

Several commercial formulations of propofol are available. The primary outcome of this study was the required dose of propofol alone or combined with lidocaine to achieve induction of general anesthesia.

METHODS

This multicenter, double-blinded trial randomized patients (American Society of Anesthesiologists physical status I-III) just before elective surgery with the use of a computer-generated list. Three different propofol 1% formulations-Diprivan (Astra-Zeneca, Cheshire, United Kingdom), Propoven (Fresenius-Kabi AG, Bad Homburg, Germany), and Lipuro (B-Braun, Melshungen AG, Germany)-were compared with either placebo (saline solution) or lidocaine 1% mixed to the propofol solution. Depth of anesthesia was automatically guided by bispectral index and by a computerized closed-loop system for induction, thus avoiding dosing bias. The authors recorded the total dose of propofol and duration of induction and the patient's discomfort through a behavioral scale (facial expression, verbal response, and arm withdrawal) ranging from 0 to 6. The authors further evaluated postoperative recall of pain using a Visual Analog Scale.

RESULTS

Of the 227 patients enrolled, 217 were available for analysis. Demographic characteristics were similar in each group. Propoven required a higher dose for induction (2.2 ± 0.1 mg/kg) than Diprivan (1.8 ± 0.1 mg/kg) or Lipuro (1.7 ± 0.1 mg/kg; P = 0.02). However, induction doses were similar when propofol formulations were mixed with lidocaine. Patient discomfort during injection was significantly reduced with lidocaine for every formulation: Diprivan (0.5 ± 0.3 vs. 2.3 ± 0.3), Propoven (0.4 ± 0.3 vs. 2.4 ± 0.3), and Lipuro (1.1 ± 0.3 vs. 1.4 ± 0.3), all differences significant, with P < 0.0001. No adverse effect was reported.

CONCLUSION

Plain propofol formulations are not equipotent, but comparable doses were required when lidocaine was concomitantly administered.

Intravenous lidocaine does not affect the anesthetic depth during rapid sequence induction and intubation as assessed by Bispectral Index monitoring: a randomized double blind study

INTRODUCTION

We investigated the impact of intravenous lidocaine on anesthetic depth, as assessed by Bispectral Index score (BIS), and hemodynamic responses to rapid sequence induction/intubation.

MATERIAL AND METHODS

Eighty-four surgical patients with risk factors for regurgitation/aspiration were randomized to receive either lidocaine 1.5 mg/kg or normal saline in a double-blind fashion. Propofol 2 mg/kg, lidocaine or normal saline, followed by rocuronium 1 mg/kg were administered intravenously and trachea was intubated under cricoid pressure application. The BIS scores were recorded before induction of anesthesia, immediately after, at 30 s and 1 min after rocuronium injection and every 30 s after intubation, for 10 min. Systolic/diastolic blood pressure and heart rate were measured before induction, immediately after and at 1 min following rocuronium administration, and every minute for 10 min after intubation.

RESULTS

Data from 78 patients were analyzed. Demograpic characteristics did not differ between the study groups. A total of 24 BIS scores were recorded for each patient. No difference was found in BIS values between lidocaine and control groups at any time point (F = 2.936, p = 0.91). Also no difference was detected in heart rate, systolic and diastolic blood pressure at any time point of the study period between the two groups (F = 0.063, p = 0.80, F = 0.007, p = 0.93, F = 0.435, p = 0.51 respectively). No episodes of significant bradycardia occurred and none of the patients reported awareness/recall of the procedure.

CONCLUSIONS

Lidocaine 1.5 mg/kg given intravenously during rapid sequence induction does not affect BIS values, or blunt the hemodymanic response to laryngoscopy and intubation.