Intravenous Lidocaine Alleviates the Pain of Propofol Injection by Local Anesthetic and Central Analgesic Effects

To Compare the Effect of Reduction in Pain on Propofol Injection after Administration of 6% Hydroxyethyl Starch versus 2% Lidocaine

BACKGROUND

Propofol injections can cause discomfort for various reasons, and the onset of this discomfort can be either sudden or delayed. Several interventions are being explored to reduce the pain associated with propofol administration. Against this backdrop, we compared the severity of pain during propofol injection in patients preadministered with either 6% hydroxyethyl starch (HES) 130/0.4 or 2% lidocaine during the induction of anesthesia.

MATERIALS AND METHODS

A comparative and observational study was conducted among 70 patients (35 in each group) undergoing elective surgery under general anesthesia. Adult patients classified as American Society of Anesthesiologists 1 and 2, aged 18-55 years, of either gender, were included. A comprehensive preanesthetic assessment was carried out. Hemodynamic variables, incidence and severity of pain, and side effects were assessed. Data analysis was performed using the SPSS version 17.

RESULTS

At 10-s postoperative period, 14.3% of participants in the HES group experienced pain, while only 2.9% of participants in the lidocaine group reported pain. At 20 s, 14.3% of participants in the HES group experienced pain, compared to 2.9% in the lidocaine group. In the HES group, 91.4% experienced no pain before losing verbal contact, whereas 97.1% in the lidocaine group reported no pain. The incidence of pain was higher in females than males at all time points ( P < 0.05).

CONCLUSION

In our observational study, both HES and lidocaine demonstrated hemodynamic stability, supporting their safe use as premedication agents. However, the differences in pain incidence suggest that lidocaine may offer advantages in certain scenarios.

Efficacy of 6% Hydroxyethyl Starch and 2% Lidocaine in Reducing the Pain of Propofol Injection: A randomised, placebo-controlled trial

Objectives

Propofol administration is associated with pain, mediated by the activation of vascular endothelium. Hydroxyethyl starch (HES) inhibits endothelial membrane activation by various nociceptive substances. Thus, this study hypothesised that pre-administration of HES can reduce pain on propofol administration. This study aimed to compare the proportion of patients with no pain on propofol administration and to compare the severity of pain and any change in pre- and post-induction haemodynamic variables.

Methods

This prospective, randomised, placebo-controlled clinical trial was conducted at Chirayu Medical College & Hospital, Bhopal, India, between August 2023 and December 2023 and included patients undergoing elective surgery under general anaesthesia. Patients were randomly assigned to 3 groups to receive either 100 mL of 6% HES followed by propofol (Group HES), 100 mL normal saline (NS) followed by propofol premixed with 2% lidocaine (Group L) or 100 mL NS followed by propofol induction (Group P).

Results

A total of 339 patients were included. The proportion of patients with no pain on propofol injection was significantly higher in the HES group (n = 75) than in the lignocaine (n = 33) and placebo (n = 13) groups (P <0.0001 each). The median pain scores were 0 (interquartile range [IQR]: 0-1), 1 (IQR: 0-1) and 2 (IQR: 2-3) in the HES, lignocaine and placebo groups, respectively. The proportion of patients with moderate (n = 44) and severe (n = 48) pain scores was significantly higher in the placebo group than in the HES and lignocaine groups (P <0.0001 each).

Conclusion

The proportion of patients experiencing pain on propofol injection was found to be significantly less with the pre-administration of 100 mL 6% HES compared to the pre-administration of lidocaine.

The efficacy of ciprofol versus propofol on anesthesia in patients undergoing endoscopy: a systematic review and meta-analysis of randomized controlled trials

INTRODUCTION

Ciprofol is a new intravenous anesthetic with a similar chemical structure to propofol. We aimed to compare the incidence of adverse actions like injection pain and time indexes of ciprofol versus propofol on anesthesia in patients undergoing endoscopy. We also compared anesthetists' satisfaction during the procedure.

METHODS

Two independent researchers (Liu and Zeng) searched the Cochrane Library, Embase databases, and PubMed for controlled clinical trials. This meta-analysis of randomized controlled trials (RCTs) was performed with the Review Manager, Stata and the Cochrane Risk-of-Bias 2 tool to evaluate methodological quality. Relative risks with 95% confidence interval (CI) were calculated for outcomes.

RESULTS

Ten trials, including 1545 patients, were examined in the current meta-analysis. During anesthesia in patients undergoing endoscopy, the incidence of injection pain was significantly reduced in the research group. Compared with propofol, the pooled risk difference (RD) with the use of ciprofol for injection pain for all the procedures was - 0.34 (95% confidence interval [CI], -0.48 to 0.19), and RR for hypotension was 0.73(95% CI:0.58 to 0.92). GRADE showed this meta-analysis has moderate or low confidence. Trial sequential analysis for mortality indicated insufficient sample size for a definitive judgment for lower incidence of hypotension.

CONCLUSION

In painless endoscopy, compared with propofol, ciprofol exhibited non-inferiority anesthesia/sedation in patients, and had a good safety profile with a lower incidence of pain on injection and may reduce the chance of hypotension. Trial sequential analysis suggested the need for more cases, and GRADE highlighted moderate certainty, emphasizing the necessity for further targeted RCTs.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42023433627.

Effects of Ranolazine and Ivabradine on Pulmonary Microhemodynamics in Experimental Model of Pulmonary Thromboembolism

We studied changes of pulmonary microhemodynamics when modeling pulmonary artery thromboembolism on perfused isolated rabbit lungs after pretreatment with ranolazine and ivabradine. The increase in pulmonary artery pressure, pulmonary vascular resistance, and pre- and postcapillary resistance was less pronounced than in control animals, but was close to that in case of pulmonary thromboembolism after pretreatment with voltage-gated Na+ channel blockers lidocaine and ropivacaine. The increase of capillary filtration coefficient inversely correlated with values of capillary hydrostatic pressure. Thus, ranolazine and ivabradine exhibit the properties of voltage-gated Na+ channel blockers mainly in smooth muscles of pulmonary arterial vessels and promote the decrease in endothelial permeability.

Efficacy of pretreatment with remimazolam on prevention of propofol-induced injection pain in patients undergoing gastroscopy

To evaluate the efficacy of remimazolam pretreatment in preventing propofol-induced injection pain (PIP) in patients undergoing gastroscopy. One hundred and forty patients (ASA I-II, aged 18-65 years, BMI 18-28 kg/m2) who were to undergo gastroscopy were randomized into either a saline group (group S) or a remimazolam group (group R) (n = 70 for each) on a computer-generated random number basis. The patients in group S received normal saline (0.1 ml/kg) and those in group R were administered remimazolam (0.1 mg/kg) via intravenous infusion for 60 s. 30 s after the injection of normal saline or remimazolam, patients received intravenously propofol (0.5 ml/s) until loss of consciousness. A different anesthesiologist who was unaware of the pretreatment was responsible for maintaining the outcome. The primary endpoint of our study was the incidence of PIP, which was measured using a 4-point scale. Secondary endpoints include the intensity of PIP, vital signs, characteristics of surgery and recovery, and adverse events. The incidence of PIP was significantly lower in group R than in group S (13 vs 51%, p < 0.001), and a lower percentage of patients presented with moderate PIP (3 vs 20%, p < 0.001). Moreover, lower consumption of propofol, shorter recovery time, and greater patient satisfaction were observed in group R than in group S. Pretreatment with remimazolam can effectively reduce the incidence and intensity of PIP in gastroscopy and shorten the recovery time without severe adverse effects.Clinical Trials Registration: Trial Registration: Chinese Clinical Trial Registry (identifier: ChiCTR2200063793). Registry time: 16/09/2022. Registry name: Efficacy of Pre-Treatment with Remimazolam on Prevention of Propofol-Induced Injection Pain in Patients Undergoing Gastroscopy. The date of patient enrollment began from 2022-9-17 to 2022-10-10. The link to the registration: https://www.chictr.org.cn/showproj.html?proj=176004 .

Evaluation of Peripheral Versus Central Route of Ondansetron as Pretreatment to Prevent Pain on the Injection of Propofol: A Randomized Controlled Study

Objective

We evaluated whether systemic ondansetron was also useful in the attenuation of propofol injection pain similar to ondansetron pretreatment.

Methods

Eighty patients were enrolled. Patients in group S received ondansetron 4 mg in saline in the right hand followed 30 min later by 5 mL saline in the left hand along with venous occlusion. Group L patients received 4 mL of saline in the right hand followed by 5 mL 4 mg ondansetron in the left hand after 30 min. Two minutes later the occlusion was released. Patients received one-fourth of the calculated total dose of propofol, and their level of pain was graded on a scale of 0 to 3, with 0 denoting no discomfort. Mean blood pressure and heart rates were also recorded. Continuous variables were checked for normality using Shapiro-Wilks test. Normal continuous variables were expressed as mean standard deviation and non-normal continuous variables were expressed as median interquartile range. T-test for the difference in the mean and paired test were used for normally distributed continuous variable whereas Mann-Whitney U test-Wilcoxon test and sign test were used for non-normally distributed variables. Repeated measure analysis of variance was used for a variable measured over different periods of time to control for the baseline effect on subsequent measures.

Results

Our results demonstrated that both systemic administration 30 min before and local venous pretreatment with ondansetron were equally beneficial in reducing pain during propofol injection.

Conclusion

A systemic administration of ondansetron may play a role in the attenuation of propofol injection pain.

Prevention of pain on injection of propofol using ice gel pack versus pre-treatment with lignocaine: a randomized controlled trial

PURPOSE

Regardless of the positive attributes of propofol, it is frequently associated with pain on injection. We compared the efficacy of topical cold thermotherapy using an ice gel pack with intravenous lignocaine pre-treatment for reducing pain on propofol injection.

METHODS

This single-blinded randomized controlled trial was conducted in 200 American Society of Anesthesiologists physical status I, II, and III patients scheduled for elective/emergency surgery under general anesthesia. The patients were randomized into two groups: the Thermotherapy group- receiving an ice gel pack proximal to the intravenous cannula for 1 min, or the Lignocaine group-receiving 0.5 mg/kg of lignocaine administered intravenously, with occlusion proximal to the site of the intravenous cannula for 30 s. The primary objective was to compare the overall incidence of pain after propofol injection. The secondary objectives included the incidence of discomfort on the application of an ice gel pack, comparison of dose of propofol needed for induction, and hemodynamic changes at induction, between the two groups.

RESULTS

Fourteen patients in the lignocaine group and 15 patients in the thermotherapy group reported pain. The incidence of pain and the distribution of pain scores were comparable among groups (p = 1.00). Patients of the lignocaine group required significantly less amount of propofol for induction as compared to the thermotherapy group (p = 0.001).

CONCLUSION

Topical thermotherapy using an ice gel pack was not found superior to lignocaine pre-treatment in alleviating pain on injection of propofol injection. However, topical cold therapy using an ice pack remains a non-pharmacological technique that is easily available, reproducible, and cost-effective. Further studies are required to prove its equivalence to lignocaine pre-treatment.

TRIAL REGISTRATION

CTRI (CTRI/2021/04/032950).

Intravenous lidocaine bolus for reducing nefopam-induced venous pain: A randomized, intrasubject comparison trial

Background and Aims

Intravenous nefopam reduces postoperative pain and opioid consumption but can cause infusion-related pain. We aimed to investigate whether lidocaine can effectively reduce this pain.

Material and Methods

This prospective, randomized, double-blind, controlled, intrasubject comparison trial included 42 patients (20-60 years) undergoing elective surgery under regional or peripheral anesthesia. In the postanesthesia care unit, two 50 mL syringes containing nefopam (20 mg) diluted in saline (100 mL) were sequentially infused in 15 min into venous catheters in the left and right arms. Patients were randomly assigned to the "left side" or "right side" group based on the arm in which a bolus of 1% lidocaine (2 mL) (study group) was administered before nefopam infusion. Normal saline (2 mL) was administered on the control side. Numerical Rating Scale scores and the incidence of pain (scores > 3) and nausea or vomiting were recorded at 1, 5, 10, and 15 min.

Results

The analysis included 42 patients (84 infusions). Compared with the placebo, lidocaine lowered the mean infusion-related pain at 1 (0.07 vs. 2.21, P < 0.001), 5 (2 vs. 4.21, P < 0.001), 10 (2.02 vs. 3.95, P < 0.001), and 15 min (1.62 vs. 3.16, P = 0.003). At 5 min, significantly higher percentages of infusion sites with moderate and higher pain scores (> 3) were observed on the control side (30.95% vs. 14.29%, P = 0.000). Seven patients exhibited nausea or vomiting (16.7%).

Conclusion

For the nefopam infusion rate and concentration that we used, a 20 mg lidocaine pretreatment bolus significantly reduces infusion-related pain.

Esketamine prevents propofol-induced injection pain: Randomized controlled trial

Background: Propofol is widely used during anesthesia. However, propofol-induced injection pain (PIP) is considered an unpleasant perioperative outcome. This study aimed to investigate the efficacy of a mixture of esketamine and propofol in preventing propofol injection pain in patients undergoing general anesthesia.

Methods: This was a prospective, double-blind, multicenter, and randomized controlled trial. We included 252 adult patients with the American Society of Anesthesiologists physical status I to II who underwent surgery under general anesthesia. Patients were randomly allocated in a 1:1:1:1 ratio to four groups (n = 63 per group). Group NS received a mixture of 1% propofol (20 ml) and 0.9% normal saline (1 ml), group ESK-4 received a mixture of 1% propofol (20 ml) and esketamine 4 mg (diluted with 0.9% normal saline, 1 ml), group ESK-12 received a mixture of 1% propofol (20 ml) and esketamine 12 mg (diluted with 0.9% normal saline, 1 ml), and group ESK-20 received a mixture of 1% propofol (20 ml) and esketamine 20 mg (diluted with 0.9% normal saline, 1 ml) as sedative drugs during anesthesia. The primary outcome was the incidence and distribution of different degrees of PIP. The secondary outcomes were vital signs, characteristics of surgery and anesthesia, and adverse events.

Results: The incidence of PIP in group ESK-20 (33.3%) was significantly lower than that in groups NS, ESK-4, and ESK-12 (63.3%, 62.2%, and 49.1%, respectively; p &lt; 0.01). The incidence of moderate PIP in group NS (33.3%) and group ESK-4 (22.6%) was higher than that in groups ESK-12 (7.5%) and ESK-20 (6.7%). The incidence of severe PIP in group NS (6.7%) and group ESK-4 (9.4%) was higher than that in groups ESK-12 (1.9%) and ESK-20 (0%). There were no differences in the vital signs, characteristics of surgery and anesthesia, or adverse events between the groups.

Conclusion: Our results indicated that the esketamine–propofol admixture reduced the incidence of PIP in patients undergoing general anesthesia without severe side effects.

Efficacy of Pre-Treatment with Remimazolam on Prevention of Propofol-Induced Injection Pain in Patients Undergoing Abortion or Curettage: A Prospective, Double-Blinded, Randomized and Placebo-Controlled Clinical Trial

Background

Propofol-induced injection pain (PIP) is a well-known problem in general anesthesia. We hypothesized that pre-treatment with remimazolam prevents PIP in patients undergoing abortion or curettage.

Materials and Methods

In this prospective, single-center, double-blinded, randomized, placebo-controlled clinical trial, adult patients aged 18 to 60 undergoing abortion or curettage were randomly assigned to three groups. Group Lido received system lidocaine (a bolus of 0.5 mg kg⁻¹, iv). Group Remi received remimazolam (a bolus of 0.1 mg kg⁻¹, iv). Group NS received identical volumes of 0.9% normal saline. Sixty seconds after the injection of lidocaine, remimazolam or saline, patients were injected with propofol at a rate of 12 mL/min until the loss of consciousness. The primary outcome was the incidence of PIP at the time of induction using 4-point scale. Secondary outcomes included propofol-induced injection pain, vital signs, the characteristics of anesthesia and surgery, and adverse events.

Results

The incidence of patients with PIP was higher in group NS than that in group Lido and group Remi (75.7, 44.3, and 42.9%, respectively, p < 0.001). The percentages of patients with moderate PIP were higher in group NS than that in group Lido and group Remi (20.0, 2.9, and 1.4%, respectively, p < 0.001). Moreover, the consumption of propofol and the incidence of adverse event (hypoxemia and chin lifting) in group Remi were lower than that in group NS and Lido, and less patients got physical movement and cough in group Remi. The recovery time in group NS was longer than that in group Lido and Remi.

Conclusion

Our findings indicate that pre-treatment with remimazolam reduced the incidence and intensity of PIP in abortion or curettage patients, equivalent to that of lidocaine without severe adverse effects.

Trial Registration

Chinese Clinical Trial Registry (identifier: ChiCTR2100041805).

Median Effective Dose of Lidocaine for the Prevention of Pain Caused by the Injection of Propofol Formulated with Medium- and Long-Chain Triglycerides Based on Lean Body Weight

OBJECTIVE

To determine the median effective dose (ED50) of prophylactic intravenous lidocaine for the prevention of propofol medium-chain triglyceride/long-chain triglyceride (MCT/LCT) emulsion injection pain.

DESIGN

Prospective trial, Dixon up-and-down sequential method.

SETTING

Operating room of a single hospital.

PATIENTS

Thirty patients aged 18-65 years with American Society of Anesthesiologists (ASA) status I or II who were scheduled for elective surgery under general anesthesia (GA) were included.

INTERVENTIONS

The initial dose of prophylactic lidocaine before propofol MCT/LCT emulsion injection was set at 0.5 mg/kg lean body weight (LBW). The lidocaine dose was adjusted according to the degree of patients' injection pain using the Dixon up-and-down sequential method.

MEASUREMENTS

The ED50 and 95% confidence intervals (CIs) of lidocaine were calculated using the Dixon-Massey formula. Vital signs and adverse effects were recorded. In the postanesthesia care unit (PACU), patients were asked if they recalled feeling any injection pain with visual analog scale (VAS) evaluation.

RESULTS

The ED50 of lidocaine for the prevention of propofol MCT/LCT emulsion injection pain was 0.306 mg/kg LBW (95% CI, 0.262-0.357 mg/kg LBW). No adverse reactions to lidocaine occurred. In the PACU, 90.9% of patients who experienced injection pain recalled this pain (VAS score, 2.8±1.8).

CONCLUSIONS

Prophylactic intravenous lidocaine (0.306 mg/kg LBW) effectively prevented propofol MCT/LCT emulsion injection pain in 50% of patients scheduled for elective surgery under GA with no adverse reaction occurring.

Pharmacological control of pain during propofol injection: a systematic review and meta-analysis

OBJECTIVE

A research was performed to review the effect of pharmacological interventions to control the propofol injection pain.

METHODS

A search of databases was performed. Randomized clinical trials comparing pharmacological interventions with placebo or active compound to reduce of propofol injection pain were selected. The outcome was the frequency of pain. Data were analyzed in three subgroups according to type of control. Random effect model was used to calculate relative risk (RR) with 95% confidence intervals (CIs).

RESULTS

Fifty-two articles with 105 studies on 7315 adults were included. The incidence of pain in intervention and control group was 40.91% and 66.27%. Combination therapy with two drugs (RR = 0.29 95% CI = (0.11, 0.75)), opioids (RR = 0.39 95% CI = (0.28, 0.54)) and 5 HT3 antagonists (RR = 0.39 95% CI = (0.30, 0.50)) were the most effective interventions compared to placebo. Combination therapy was the most effective intervention compared to lidocaine as control (RR = 0.51 95% CI = (0.46, 0.55)). Opioids were the most effective intervention compared to long chain triglyceride propofol as control (RR = 0.27 95% CI = (0.15, 0.49)).

CONCLUSION

Pretreatment with two different drugs, opioids and surprisingly 5 HT3 antagonists were the most effective interventions compared to placebo. Combination therapy was the most effective versus lidocaine as control.

Lidocaine coinfusion alleviates vascular pain induced by hypertonic saline infusion: a randomized, placebo-controlled trial

Background

Hypertonic saline solution has been frequently utilized in clinical practice. However, due to the nonphysiological osmolality, hypertonic saline infusion usually induces local vascular pain. We conducted this study to evaluate the effect of lidocaine coinfusion for alleviating vascular pain induced by hypertonic saline.

Methods

One hundred and six patients undergoing hypertonic saline volume preloading prior to spinal anesthesia were randomly allocated to two groups of 53 each. Group L received a 1 mg/kg lidocaine bolus followed by infusion of 2 mg/kg/h through the same IV line during hypertonic saline infusion; Group C received a bolus and infusion of normal saline of equivalent volume. Visual analogue scale (VAS) scores of vascular pain were recorded every 4 min.

Results

The vascular pain severity in Group L was significantly lower than that in Group C for each time slot (P < 0.05). The overall incidence of vascular pain during hypertonic saline infusion in Group L was 48.0%, which was significantly lower than the incidence (79.6%) in Group C (P < 0.05).

Conclusion

Lidocaine coinfusion could effectively alleviate vascular pain induced by hypertonic saline infusion.

Trial registration

Chinese Clinical Trial Registry, number: ChiCTR1900023753. Registered on 10 June 2019.

The analgesic efficacy and duration of lidocaine on vascular pain induced by hypertonic saline infusion: a double-blinded, randomized control trial

PURPOSE

To determine the analgesic efficacy and analgesic duration of lidocaine 20 mg and 40 mg on eliminating the vascular pain associated with hypertonic saline infusion.

METHOD

Patients who complained pain during infusion of hypertonic saline were randomized into three groups. They received normal saline (Group C), or lidocaine 20 mg (Group L20), or lidocaine 40 mg (Group L40). An electronic stopwatch was used to record the time to onset (T1) and the time to termination (T2) of the analgesic effect, and the analgesic duration (AD) was calculated as T2 - T1.

RESULTS

The incidence of pain elimination was significantly higher in both of the lidocaine groups (83.3 and 56.1% in Groups L40 and L20, respectively) than in the saline group (16.3%). Furthermore, lidocaine 40 mg was significantly more effective than 20 mg in eliminating the pain. The analgesic duration was significantly longer in Group L40 than in Group L20 (211.4 ± 50.2 vs. 130.3 ± 39.5 s, P < 0.001) and Group C (211.4 ± 50.2 vs. 45.1 ± 14.5 s, P < 0.001), and the analgesic duration in Group L20 was significantly longer than in Group C (P < 0.001). The incidence of transient tinnitus/dizziness was significantly higher in Group L40 than in Group L20 (19.0 vs. 2.4%, P < 0.05).

CONCLUSION

A single bolus of Lidocaine was effective in eliminating the pain induced by hypertonic saline infusion, but just for a short period of time. Lidocaine (without venous occlusion) only provides a short analgesic duration for local vein.