Prevention of microemulsion propofol injection pain: a comparison of a combination of lidocaine and ramosetron with lidocaine or ramosetron alone

Multiple assessments of non-inferiority trials with ordinal endpoints

Non-inferiority (NI) trials are implemented when there is a practical demand to search for alternatives to standard therapies, such as to reduce side effects. An experimental treatment is considered non-inferior to the standard treatment when it exhibits clinically non-significant loss of efficacy. Ordinal categorical responses are frequently observed in clinical trials. It has been reported that responses measured using an ordinal scale produce more informative analysis than when responses collapse into binary outcomes. We study the NI trials using ordinal endpoints. We propose a latent variable model for ordinal categorical responses. Based on the proposed latent variable model, the mean efficacy of the different treatments is denoted by the corresponding mean parameter of the underlying continuous distributions. A two-step procedure is proposed for model identification and parameter estimation. A non-inferiority analysis can then be conducted based on the latent variable model and the corresponding estimation procedure. We also develop a method and an algorithm to produce an optimal sample size configuration based on the proposed testing procedure. Two clinical examples are provided for demonstrative purposes.

Clinical Study on the Combination of Transcutaneous Electrical Acupoint Stimulation and Lidocaine for Preventing Propofol Injection Pain

Purpose

Propofol is a widely used intravenous anesthetic in clinical practice. Lidocaine pretreatment is currently the most commonly used method to reduce the pain of propofol injection. However, propofol injection pain has not been eliminated and its incidence remains high. Transcutaneous electrical acupoint stimulation is a green therapy that combines transcutaneous electrical nerve stimulation therapy with the traditional acupuncture therapy of our motherland. This study investigated the effectiveness of transcutaneous electrical acupoint stimulation (TEAS) combined with lidocaine in preventing propofol injection pain and determined whether it can reduce postoperative complications and promote rapid postoperative recovery of patients.

Patients and Methods

A total of 220 women scheduled to undergo hysteroscopic surgery were enrolled in the study. The included patients were randomly divided into four groups of 55 patients each: normal saline group (group K), lidocaine group (group L), TEAS group (group T), and lidocaine + TEAS group (group L + T). Patients in group K received 2 mL saline (0.9% NaCl) pre-injection before anesthesia induction. Group L received 40 mg lidocaine pre-injection (2 mL of 2% lidocaine) before anesthesia induction. Group T received 30 min of transcutaneous electrical stimulation at bilateral election Hegu, Neiguan, and 2 mL saline pre-injections before anesthesia induction. Group L + T received TEAS and lidocaine pre-injection.

Results

The VAS scores and the four-point verbal rating scale of propofol injection were significantly different among the four groups. The prevalence of nausea, vomiting, abdominal pain, and abdominal distension after surgery among the four groups were statistically different. The bleeding days after surgery were significantly different among the four groups.

Conclusion

TEAS combined with lidocaine pre-injection reduced the incidence of propofol injection pain and significantly reduced patients’ pain levels compared with single lidocaine pre-injection. TEAS can also reduce the incidence of postoperative nausea and vomiting, abdominal pain, and abdominal distension, shorten postoperative bleeding days, and accelerate the postoperative recovery of patients.

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.

A comparative study of attenuation of propofol-induced pain by lignocaine, ondansetron, and ramosetron

Background and Aims:

Propofol is widely used for induction of anaesthesia, although the pain during its injection remains a concern for all anaesthesiologists. A number of techniques have been adopted to minimise propofol-induced pain. Various 5-hydroxytryptamine-3 antagonists have shown to reduce propofol-induced pain. Hence, this placebo-controlled study was conducted to compare the efficacy of ondansetron, ramosetron and lignocaine in terms of attenuation of propofol-induced pain during induction of anaesthesia.

Methods:

Hundred and fifty adult patients, aged 18–60 years, posted for various elective surgical procedures under general anaesthesia were randomly assigned to three groups of 50 each. Group R received 0.3 mg of ramosetron, Group L received 0.5 mg/kg of 2% lignocaine and Group O received 4 mg of ondansetron. After intravenous (IV) pre-treatment of study drug, manual occlusion of venous drainage was done at mid-arm with the help of an assistant for 1 min. This was followed by administration of propofol (1%) after release of venous occlusion. Pain was assessed with a four-point scale. Unpaired Student's t-test and Chi-square test/Fisher's exact test were used to analyse results.

Results:

The overall incidence and intensity of pain were significantly less in Groups L and R compared to Group O (P ≤ 0.001). The incidence of mild to moderate pain in Groups O, R and L was 56%, 26% and 20%, respectively. The incidence of score ‘0’ (no pain) was significantly higher in Group L (76%) and Group R (72%) than Group O (34%) (P < 0.001).

Conclusion:

Pre-treatment with IV ramosetron 0.3 mg is equally effective as 0.5 mg/kg of 2% lignocaine in preventing propofol-induced pain and both were better than ondansetron.

Lidocaine for reducing propofol-induced pain on induction of anaesthesia in adults

BACKGROUND

Pain on propofol injection is an untoward effect and this condition can reduce patient satisfaction. Intravenous lidocaine injection has been commonly used to attenuate pain on propofol injection. Although many studies have reported that lidocaine was effective in reducing the incidence and severity of pain, nevertheless, no systematic review focusing on lidocaine for preventing high-intensity pain has been published.

OBJECTIVES

The objective of this review was to determine the efficacy and adverse effects of lidocaine in preventing high-intensity pain on propofol injection.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 10), Ovid MEDLINE (1950 To October 2014), Ovid EMBASE (1988 to October 2014), LILACS (1992 to October 2014) and searched reference lists of articles.We reran the search in November 2015. We found 11potential studies of interest, those studies were added to the list of 'Studies awaiting classification' and will be fully incorporated into the formal review findings when we update the review.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) using intravenous lidocaine injection as an intervention to decrease pain on propofol injection in adults. We excluded studies without a placebo or control group.

DATA COLLECTION AND ANALYSIS

We collected selected studies with relevant criteria. We identified risk of bias in five domains according to the following criteria: random sequence generation, allocation concealment, adequacy of blinding, completeness of outcome data and selective reporting. We performed meta-analysis by direct comparisons of intervention versus control. We estimated the summary odds ratios (ORs) and 95% confidence intervals using the random-effects Mantel-Haenszel method in RevMan 5.3. We used the I(2) statistic to assess statistical heterogeneity. We assessed overall quality of evidence using the GRADE approach.

MAIN RESULTS

We included 87 studies, 84 of which (10,460 participants) were eligible for quantitative analysis in the review. All participants, aged 13 years to 89 years, were American Society of Anesthesiologists (ASA) I-III patients undergoing elective surgery. Each study was conducted in a single centre in high- , middle- and low-income countries worldwide. According to the risk of bias assessment, all except five studies were identified as being of satisfactory methodological quality, allowing 84 studies to be combined in the meta-analysis. Five of the 84 studies were assessed as high risk of bias: one for participant and personnel blinding, one for incomplete outcome data, and three for other potential sources of bias.The overall incidence of pain and high-intensity pain following propofol injection in the control group were 64% (95% CI 60% to 67.9%) and 38.1% (95% CI 33.4% to 43.1%), respectively while those in the lidocaine group were 30.2% (95% CI 26.7% to 33.7%) and 11.8% (95% CI 9.7% to 13.8%). Both lidocaine admixture and pretreatment were effective in reducing pain on propofol injection (lidocaine admixture OR 0.19, 95% CI 0.15 to 0.25, 31 studies, 4927 participants, high-quality evidence; lidocaine pretreatment OR 0.13, 95% CI 0.10 to 0.18, 43 RCTs, 4028 participants, high-quality evidence). Similarly, lidocaine administration could considerably decrease the incidence of pain when premixed with the propofol (OR 0.19, 95% CI 0.15 to 0.24, 36 studies, 5628 participants, high-quality evidence) or pretreated prior to propofol injection (OR 0.14, 95% CI 0.11 to 0.18, 52 studies, 4832 participants, high-quality evidence). Adverse effects of lidocaine administration were rare. Thrombophlebitis was reported in only two studies (OR not estimated, low-quality evidence). No studies reported patient satisfaction.

AUTHORS' CONCLUSIONS

Overall, the quality of the evidence was high. Currently available data from RCTs are sufficient to confirm that both lidocaine admixture and pretreatment were effective in reducing pain on propofol injection. Furthermore, there were no significant differences of effect between the two techniques.

Multiple comparisons with two controls for ordered categorical responses

In clinical studies, ordered categorical responses are common. To compare the efficacy of several treatments with a control for ordinal responses, the normal latent variable model has recently been proposed. This approach conceptualizes the responses as manifestations of an underlying continuous normal variable. In this article, we extend this idea to develop the multiple comparison method for use when there are two controls in the clinical trial. The proposed method is constructed such that the familywise type I error rate is controlled at a prespecified level. In addition, for a given level of test power, the procedure to evaluate the required sample size is provided. The proposed testing procedure is also illustrated by an example from a clinical study.

"Micro to macro (M2M)"--A novel approach for intravenous delivery of propofol

PURPOSE

Propofol emulsions have limited shelf life and safety concerns for injection. Microemulsions of propofol are thermodynamically stable and simpler to manufacture, but cause additional pain on injection. We propose a novel micro to macro (M2M) approach of destabilizing a microemulsion immediately prior to injection.

METHODS

Microemulsions of propofol were prepared at two to three times the drug loadings of commercial formulations. We determined suitable microemulsion compositions which destabilize into macroemulsions after two or three fold dilutions with water. Droplet growth after dilution was measured with dynamic light scattering. Increasing solution turbidity after dilution was also measured optically with millisecond resolution. Experimental data was analyzed in the context of a coalescence model.

RESULTS

Microemulsions rapidly coalesce into larger droplet size macroemulsions after dilution according to the phase diagram shift. The resulting macroemulsions are metastable retaining their droplet size for several hours. Droplet growth occurs on the order of seconds and a metastable size of about 1 micron is reached in minutes. Rates of droplet growth and metastable droplet sizes depend on the surfactant composition. The coalescence model predicts droplet growth with good agreement but only after accounting for the finite probability of coalescence from each collision.

CONCLUSIONS

The M2M concept has been demonstrated for the anesthetic drug propofol which may improve stability and manufacturability in addition to reducing pain on injection. This approach could be adapted to other hydrophobic vesicant drugs as well.

Effects of pretreatment with intravenous palonosetron for propofol-remifentanil-based anesthesia in breast and thyroid cancer surgery: a double-blind, randomized, controlled study

Background

We postulated that palonosetron, a novel antiemetic agent, might have the effect of alleviating injection pain from propofol and rocuronium. A double-blind, controlled study was undertaken to evaluate the effect of palonosetron on injection pain during total intravenous anesthesia and postoperative nausea and vomiting (PONV) using propofol-remifentanil in breast and thyroid cancer surgery.

Methods

Sixty patients were randomly allocated to one of two groups. Before injection of propofol and rocuronium, patients in group S (n = 30) received 4 ml of saline and patients in group P (n = 30) received 75 µg (1.5 ml) of palonosetron mixed with 2.5 ml of saline (n = 30). Patients were evaluated by a blinded anesthesiologist with regard to the scoring of injection pain of propofol, withdrawal response by rocuronium, PONV, shivering, postoperative pain, recall of pain, and overall satisfaction.

Results

The differences between groups in the incidence of injection pain due to propofol and rocuronium were insignificant. However, in group P, the severity of propofol-induced injection pain (3% vs. 33%, P = 0.003) and postoperative pain (P = 0.038) was significantly lower during the first 12 h after surgery. No differences were observed between the groups with respect to PONV, shivering, recall of pain, and overall satisfaction.

Conclusions

We concluded that pretreatment of palonosetron was effective to reduce the severity of propofol-induced injection pain and early postoperative pain, although it did not reduce the incidence of injection pain from propofol and rocuronium.

Efficacy and safety of flurbiprofen axetil in the prevention of pain on propofol injection: a systematic review and meta-analysis

Background

Pain on injection is an acknowledged adverse effect (AE) of propofol administration for the induction of general anesthesia. Flurbiprofen axetil has been reported to reduce the pain of injection. However, results of published papers on the efficacy of flurbiprofen axetil in managing pain on injection of propofol are inconsistent.

Material/Methods

We conducted a comprehensive meta-analysis of studies to appraise the efficacy and safety of flurbiprofen axetil for controlling pain induced by propofol injection. The pooled risk ratio (RR) with corresponding 95% confidence intervals (CI) was calculated employing fixed- or random-effects models, depending upon the heterogeneity of the included trials.

Results

Compared with the placebo group, flurbiprofen axetil allows more patients to have no pain (RR 3.51, 95% CI 2.22–5.55, p=0.000), and decreases the cumulative number of patients with mild, moderate, and severe pain on injecting propofol (RR 0.70, 95% CI 0.58–0.86, p=0.000; RR 0.59, 95% CI 0.46–0.75, p=0.000; RR 0.25, 95% CI 0.16–0.38, p=0.000, respectively). In the stratified analysis by the doses, flurbiprofen axetil at a dose of over 50 mg was found to be effective in reducing propofol-induced pain on injection; however, there were no significant differences in relieving pain between treatment and placebo groups with flurbiprofen axetil at a dose of 25 mg. In terms of drug safety, there were no adverse effects (AEs) reported between flurbiprofen axetil-based regimens and placebo regimens.

Conclusions

Flurbiprofen axetil, an injectable prodrug of flurbiprofen, can significantly prevent or relieve the pain induced by propofol injection. More studies are required to assess its adverse effects.

Prevention of propofol injection pain: Comparison between lidocaine and ramosetron

BACKGROUND

Propofol causes a high incidence of pain during intravenous (IV) injection. The aim of this randomized, placebo-controlled, double-blinded study was to determine whether pre-treatment with IV ramosetron, used for prophylaxis of postoperative nausea and vomiting (PONV), would reduce propofol-induced pain as an equivalent to lidocaine.

MATERIALS AND METHODS

Hundred and twenty American Society of Anesthesiologists grade (ASA) I and II patients were randomly assigned into three groups (40 in each). Group N received 2 ml of 0.9% saline, Group L received 2 ml of lidocaine, and Group R received 2 ml of ramosetron. Mid forearm was occluded manually before injection and released after 1 min and then propofol was injected over 5 s. Patients were observed and questioned 15 s later if they had pain in the arm and pain was scored on a four-point scale: 0 = no pain, 1 = mild pain, 2 = moderate pain, and 3 = severe pain. Unpaired Student's t-test and chi-square test/Fisher' exact test were used to analyze results.

RESULTS

The incidence of pain in groups N, L, and R were 65, 35, and 30%, respectively. Pain was reduced significantly in the groups L and R (P < 0.05). Two patients each in Groups L and R (5% each) had moderate and severe pain. This difference in pain was statistically insignificant, but when compared to Group N (25 and 30%, respectively) it was statistically significant.

CONCLUSION

Pretreatment with ramosetron 0.3 mg and lidocaine 40 mg are equally effective in preventing pain from propofol injection.

Analgesic effects of palonosetron in the intravenous propofol injection

Background

Propofol is a good induction agent, but it has the disadvantage of causing pain on intravenous injection. The incidence of propofol-induced pain is approximately 70%. Palonosetron is a novel second-generation 5-hydroxytryptamine type 3 (5-HT3) receptor antagonist. We presumed that palonosetron would be effective in reducing the occurrence of propofol-induced pain based on similar mechanisms to other 5-HT3 receptor antagonists.

Methods

Eighty patients were randomized to either Group N (0.9% sodium chloride [normal saline] 2 ml, n = 40) or Group P (palonosetron 0.075 mg, 2 ml, n = 40). Patients were intravenously given a 2 ml pretreatment solution, containing either palonosetron 0.075 mg or normal saline. Following pretreatment with 2 ml of palonosetron 0.075 mg or normal saline, we manually occluded venous drainage midarm with the help of an assistant. One minute later, we released the occlusion of venous drainage. This was followed by a 5-second propofol injection at 25% of the total calculated doses. Patients were then interviewed about whether or not they experienced propofol-induced pain.

Results

Overall, the incidence of propofol-induced pain was 60% in the normal saline group and 27.5% in the palonosetron group. No patients in the palonosetron group experienced severe pain. The incidence of propofol-induced pain was significantly lower in the palonosetron group compared to the normal saline group (P < 0.01).

Conclusions

Following pretreatment with palonosetron, 72.5% of patients experienced a decrease in the occurrence of propofol-induced pain.

The effect of gender on EC(50) of remifentanil to prevent pain during injection of microemulsion propofol

Background

Propofol injection pain is an unpleasant experience to patients and its prevalence can be influenced by age and gender. We determined the half maximal effective concentration (EC₅₀) of remifentanil for preventing the microemulsion propofol injection pain in the male and female adult groups.

Methods

After institutional review board approval, a total of 60 patients were assigned into 2 groups depending on their gender: group M (male, 20-65 yr) and group F (female, 20-65 yr). Anesthesia was induced with propofol and remifentanil, by a target-controlled infusion. Target effect-site concentration (Ce) of propofol and remifentanil for the first patient started at 4.0 ug/ml and 4.0 ng/ml. Ce of remifentanil for each subsequent patient was determined by the response of the previous patient by the Dixon's up-and-down method (DUDM) with an interval of 0.2 ng/ml. After equilibration of plasma and effect site remifentanil concentration, propofol was administered, and the pain responses were observed.

Results

The remifentanil EC₅₀ was 3.8 ± 0.2 and 2.7 ± 0.2 ng/ml in groups M and F, respectively, by DUDM. From Probit regression model, the remifentanil EC₅₀ was 3.7 (3.0-4.3) and 2.7 (1.8-2.9) ng/ml in groups M and F, respectively.

Conclusions

The remifentanil EC₅₀ for preventing the moderate to severe injection pain of propofol was higher in males than in females.