Is propofol injection pain really important to patients?

Comparison of the efficacy and safety of ciprofol and propofol for ERCP anesthesia in older patients: A single-center randomized controlled clinical study

STUDY OBJECTIVES

Ciprofol is a novel agonist at the gamma-aminobutyric acid-A (GABAA) receptor, exhibiting better cardiovascular stability and rapid recovery. The objective of this study was to compare the efficacy and safety of ciprofol and propofol for endoscopic retrograde cholangiopancreatography (ERCP) anesthesia in older patients.

DESIGN

A single-center, randomized, parallel controlled clinical study.

SETTING

General Hospital of Northern Theater Command.

PATIENTS

We recruited 284 patients and intended to conduct ERCP from November 2021 to June 2022.

INTERVENTIONS

Patients scheduled for ERCP were randomly assigned to two groups (n = 142 each): ciprofol group (anesthesia induction 0.3-0.4 mg/kg, anesthesia maintenance 0.8-1.2 mg/kg/h) and propofol group (anesthesia induction 1.5-2.0 mg/kg, anesthesia maintenance 4-12 mg/kg/h).

MEASUREMENTS

The primary outcome was sedation success rate, defined as the proportion of patients with successful anesthesia induction. Secondary outcomes encompassed the time of successful induction, the time of complete recovery, the time of leaving the room and the incidence rate of adverse events (hypoxemia, hypotension and injection pain).

MAIN RESULTS

The success rate of sedation in both groups was 100 %. The 95 % CI of the difference of sedation success rate was (- 2.63 %, 2.63 %), and the lower limit was greater than the non-inferiority limit of -8 %.The time of successful sedation induction in ciprofol group (38.4 ± 6.5 s) was longer than that in propofol group (30.6 ± 6.2 s, p < 0.05).The time of complete recovery in ciprofol group (12.8 ± 5.8 min) was shorter than that in propofol group (16.9 ± 5.0 min, p < 0.05). The time of leaving the room in ciprofol group (21.8 ± 5.8 min) was shorter than those in propofol group (25.9 ± 5.1 min, p < 0.05). The incidence of injection pain in ciprofol group (2 %) was lower than that in the propofol group (25 %, p < 0.05). Other outcomes didn't show statistical differences.

CONCLUSIONS

Compared with propofol, ciprofol exhibited a comparable level of sedation in older patients undergoing ERCP, and recovery was safe and rapid with less injection pain.

TRIAL REGISTRATION

www.chictr.org.cn (Registration number ChiCTR2100053386, Registration date November 20, 2021).

Efficacy and safety of ciprofol versus propofol for induction of general anaesthesia or sedation: A systematic review and meta-analysis of randomised controlled trials

Background and Aims

Propofol has been used in medical practice as an anaesthetic drug for producing and sustaining general anaesthesia due to its advantages. However, it also has drawbacks, including injection-related discomfort. Recently, ciprofol has emerged as a promising anaesthetic drug that may overcome many drawbacks associated with propofol. In this systematic review and meta-analysis, we assess the efficacy and safety of ciprofol compared to propofol in different anaesthesia procedures.

Methods

The study protocol was registered in the International Prospective Register of Systematic Reviews (ID: CRD42023458170). Central, PubMed, EMBASE, Scopus and WOS were searched for English literature until 26 February 2024. Meta-analysis was performed using RevMan. The risk of bias was assessed using the RoB 2.0 tool. Results were reported as risk ratios (RRs), mean differences (MDs) and 95% confidence intervals (CIs).

Results

Nineteen randomised controlled trials were included in our analysis, with 2841 participants. There was no difference between ciprofol and propofol in the success rate of endoscopy (RR: 1.01, 95% CI: 0.99, 1.02; P = 0.44), while ciprofol showed a significant increase in the success rate of general anaesthesia/sedation (RR: 1.01, 95% CI: 1.00, 1.02; P = 0.04). Ciprofol showed significantly lower pain on injection (RR: 0.14, 95% CI: 0.09, 0.22; P < 0.001), lower adverse events (RR: 0.80, 95% CI: 0.69, 0.92; P = 0.002) and higher patient satisfaction (standardised mean difference (SMD): 0.36, 95% CI: 0.24, 0.48; P < 0.001).

Conclusion

Ciprofol exhibited a comparable efficacy to propofol in inducing general anaesthesia and sedation with fewer adverse events, less pain on injection and higher patient satisfaction. These collective findings may suggest that ciprofol can be used as an alternative drug to ensure effective general anaesthesia/sedation induction in the future.

Why sedative hypnotics often fail in development

PURPOSE OF REVIEW

Drug development to support anaesthesia and sedation has been slow with few candidates emerging from preclinical discovery and limited innovation beyond attempted reformulation of existing compounds.

RECENT FINDINGS

The market is well supported by low-cost generic products and development compounds have not been shown to improve patient outcomes or possess other distinctive characteristics to justify the cost of development.

SUMMARY

To make progress in a large-volume, low margin and highly competitive environment requires meaningful advances in relevant basic science. Opportunities exist, but probably require bolder initiatives than further attempts at reformulation or fiddling with the structure of propofol. Extending development ambitions to include nonanaesthesiologist providers challenges professional boundaries but may facilitate cost-effective changes in patterns of care.

Efficacy and safety of Ciprofol compared with Propofol during general anesthesia induction: A systematic review and meta-analysis of randomized controlled trials (RCT)

BACKGROUND

Ciprofol, a newer entrant with similarities to propofol, has shown promise with a potentially improved safety profile, making it an attractive alternative for induction of general anesthesia. This meta-analysis aimed to assess the safety and efficacy of ciprofol compared with propofol during general anesthesia induction.

METHODS

A comprehensive literature search was conducted using PubMed, Clinical Trial.gov, and Cochrane Library databases from inception to July 2023 to identify relevant studies. All statistical analyses were conducted using R statistical software version 4.1.2.

RESULTS

Thirteen Randomized Controlled Trials (RCTs) encompassing a total of 1998 participants, were included in our analysis. The pooled analysis indicated that Ciprofol was associated with a notably lower incidence of pain upon injection [RR: 0.15; 95% CI: 0.10 to 0.23; I^2 = 43%, p < 0.0000001] and was non-inferior to propofol in terms of anesthesia success rate [RR: 1.00; 95% CI: 0.99 to 1.01; I^2 = 0%; p = 0.43]. In terms of safety, the incidence of hypotension was significantly lower in the ciprofol group [RR:0.82; 95% CI:0.68 to 0.98; I^2 = 48%; p = 0.03]. However, no statistically significant differences were found for postoperative hypertension, bradycardia, or tachycardia.

CONCLUSION

In conclusion, Ciprofol is not inferior to Propofol in terms of its effectiveness in general anesthesia. Ciprofol emerges as a valuable alternative sedative with fewer side effects, especially reduced injection pain, when compared to Propofol.

SUMMARY

Propofol, frequently utilized as an anesthetic, provides swift onset and quick recovery. However, it has drawbacks such as a narrow effective dosage range and a high occurrence of adverse effects, particularly pain upon injection. Ciprofol, a more recent drug with propofol-like properties, has demonstrated promise and may have an improved safety profile, making it a compelling alternative for inducing general anesthesia. This meta-analysis compared the safety and effectiveness of Ciprofol with Propofol for general anesthesia induction in a range of medical procedures, encompassing thirteen Randomized Controlled Trials (RCTs) and 1998 individuals. The pooled analysis indicated that Ciprofol was associated with a notably lower incidence of pain upon injection [RR: 0.15; 95% CI: 0.10 to 0.23; I^2 = 43%, p < 0.0000001] and was non-inferior to propofol in terms of anesthesia success rate [RR: 1.00; 95% CI: 0.99 to 1.01; I^2 = 0%; p = 0.43]. In terms of safety, the incidence of hypotension was significantly lower in the ciprofol group [RR:0.82; 95% CI:0.68 to 0.98; I^2 = 48%; p = 0.03]. However, no statistically significant differences were found for hypertension, bradycardia, or tachycardia. In conclusion, ciprofol is equally effective at inducing and maintaining general anesthesia as propofol. When compared to propofol, ciprofol is a better alternative sedative for operations including fiberoptic bronchoscopy, gynecological procedures, gastrointestinal endoscopic procedures, and elective surgeries because it has less adverse effects, most notably less painful injections.

Characteristics that increase the risk for pain on propofol injection

BACKGROUND

Propofol for anesthesia has become increasingly popular for endoscopic procedures. However, pain on propofol injection (POPI) remains an issue with administration. The primary endpoint of this study was to identify patient characteristics and factors, such as IV site and gauge, that could predict the occurrence of POPI.

METHODS

This was a prospective chart review study of 291 patients undergoing endoscopic procedures. The patient's demographics, intravenous (IV) site, and gauge were extrapolated. POPI was scored 0-3: 0 for no pain, 1 for minimal discomfort or awareness of sensation, 2 for discomfort but manageable/tolerable, and 3 for severe discomfort with writhing.

RESULTS

291 patient charts were reviewed. One patient was excluded for a lower extremity IV site. 225 (77.6%) had no pain, 48 (16.6%) grade 1 pain, 16 (5.5%) grade 2 pain, and 1 (0.3%) grade 3 pain. 137, 13, and 140 patients respectively had antecubital (AC), forearm, and hand IVs. Zero patients with an AC IV experienced a score greater than 1. Compared to AC, forearm IVs with pain of 2-3 had a univariate odds ratio (OR) of 11.3 (0.66,1.92; p-value < 0.001), and hand IVs had a univariate OR of 18.8 (2.46,143.3; p-value < 0.001) with a multivariable OR 15.2 (1.93,118.9; p-value 0.004). Patients with anxiety/depression and pain had a univariate OR 2.31 (1.09, 7.27; p-value 0.031) with a multivariable OR 2.85 (1.06, 7.74; p-value 0.039). SSRI/SNRI use had a univariate OR 1.56 (0.57,4.28; p-value 0.38). Alcohol use had a univariate OR 1.24 (0.39,3.91; p-value 0.71). Narcotic use had a Univariate OR 6.18 (1.49,25.6; p-value 0.012). Diabetic patients had a univariate OR of 1.42 (0.45,4.48; p-value 0.55). Chronic pain had a univariate OR of 3.11 (1.04,9.28; p-value 0.042). Females had a univariate OR 0.98 (0.37,2.63; p-value 0.95).

CONCLUSION

This study identified potential characteristics for having POPI. The incidence of POPI was statistically significant in patients with hand and forearm IVs compared to AC IV sites, larger IV gauges, history of depression/anxiety, history of chronic narcotic use, fibromyalgia, and chronic pain syndromes. This shows the potential of premedicating with analgesics or using AC sites on these select patients to help reduce the risk of POPI.

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 .

Study on the effectiveness and safety of ciprofol in anesthesia in gynecological day surgery: a randomized double-blind controlled study

BACKGROUD

ciprofol is a new type of intravenous anesthetic, which is a tautomer of propofol, with the characteristics of less injection pain, less respiratory depression and higher potency, but little clinical experience. The aim of this study was to observe the efficacy and safety of the application of ciprofol in ambulatory surgery anesthesia in gynecology.

METHODS

128 patients were selected to undergo gynecological day surgery under general anesthesia, and the patients were randomly divided into the ciprofol group and the propofol group, with 64 cases in each group. During anesthesia induction, the ciprofol group was infused at a time limit of 0.5 mg/kg for one minute, and the propofol group was infused at a time limit of 2 mg/kg for 1 min. The overall incidence of adverse events was the primary outcome for this study, while secondary outcomes included the success rate of anesthesia induction, the time of loss of consciousness, the time of awakening,top-up dose and frequency of use of rescue drugs.

RESULTS

The overall incidence of adverse events was significantly lower in the ciprofol group compared with the propofol group (56.2% vs. 92.2%,P < 0.05). The success rate of anesthesia induction of ciprofol and propofol group was 100.0%. The time of loss of consciousness of the ciprofol group was longer than that of the propofol group (1.6 ± 0.4 min vs. 1.4 ± 0.2 min, P < 0.05). The time of awakening was not statistically significant (5.4 ± 2.8 min vs. 4.6 ± 1.6 min, P > 0.05). The number of drug additions and resuscitation drugs used were not statistically significant.

CONCLUSIONS

Compared with propofol, ciprofol had a similar anesthetic effect in gynecological ambulatory surgery, and the incidence of adverse events in the ciprofol group was lower.

Deep breathing alleviates propofol-induced pain: a prospective, randomized, single-blind study

PURPOSE

Propofol is commonly used to induce general anesthesia; however, the pain caused during propofol injection is a disadvantage. This study aimed to assess whether deep breathing attenuates propofol injection pain.

METHODS

This prospective, single-blind, randomized controlled study included 200 patients who were scheduled to undergo elective surgery under general anesthesia and randomly and equally divided them into group D and group C. The observers were not blinded to the pain-relieving modality, but each patient was blinded. Group D patients were requested to repeatedly take deep breaths throughout general anesthesia induction with propofol. Group C patients were requested to breathe in the usual manner. The intensity of propofol injection pain was evaluated using the visual analog scale (VAS). Furthermore, we recorded the patients' pain expressions, including grimace or hand-withdrawal, and the recalled pain measured using a VAS in the post-anesthetic care units (PACU).

RESULTS

Compared with patients in group C, those in group D showed significantly reduced VAS scores for propofol injection pain (20 [interquartile range (IQR): 0-48] vs. 37 [IQR 9-65], P = 0.017) and recalled pain in the PACU (16 [IQR 0-32] vs. 26 [IQR 0.5-51], P = 0.031). Further, the grimace incidence was significantly lower in group D (18%) than in group C (45%) (P < 0.001). There was no significant difference in the incidence of pain at induction, recalled pain, or hand-withdrawal.

CONCLUSIONS

Deep breathing could be an easy, safe, and inexpensive method for reducing pain during propofol injection.

Determining the effective dose of esketamine for mitigating pain during propofol injection by Dixon's up-and-down method: a double-blind, prospective clinical study of drug dose response

BACKGROUND

Propofol is an intravenous (IV) anesthetic medication widely used for procedural sedation, operative anesthesia, and in intensive care unit (ICU), but the incidence of pain during IV infusion can reach 28-90%. Ketamine can attenuate pain associated with IV propofol injection through local and central analgesic effects. Ketamine is gradually being transitioned to its S-enantiomer, esketamine, which has a similar mechanism of action. The purpose of our study is to determine the half effective dose (ED₅₀), 95% effective dose (ED₉₅), and 99% effective dose (ED₉₉) of esketamine for attenuating propofol injection pain using Dixon's up-and-down method to provide a reference for optimal dose selection for surgeries and procedures.

METHODS

Thirty gynecological patients undergoing hysteroscopic surgery were enrolled in a sequential method to determine the effective dose of esticketamine for analgesic propofol injection in order of operation. This study was based on the sequential allocation up-and-down rule designed by Dixon, and each patient was induced by esticketamine combined with propofol. During induction, the target dose of esketamine was first given via venous access in the left hand of the patient, and 30 s later, a fixed dose of 2 mg/kg (1 ml/s) of propofol was given. Patient perception of pain was scored with the verbal rating scale (VRS) every 5 s after the start of the propofol infusion, and the evaluation was stopped once the patient became unresponsive. The dosage of esketamine was increased or decreased up or down according to the patient's pain response. The initial dose of esketamine was 0.2 mg/kg, and the gradient of adjacent dose was 0.02 mg/kg. If the pain response assessment of the upper patient was positive (+), the dose of esselketamine in the next patient was increased by 0.02 mg/kg; if the pain response assessment of the upper patient was negative (-), the dose of esselketamine in the next patient was decreased by 0.02 mg/kg. The tests were carried out sequentially, with the pain response changing from positive to negative or from negative to positive, and the tests were stopped after at least 6 crossover points, and the effective dose of esticketamine was calculated using probit probability regression analysis.

RESULTS

The ineffective group comprised patients with a positive pain response and the effective group comprised patients with a negative pain response. The 95% CI was set as the confidence interval of effective dose ED value，and we found esketamine's ED₅₀ = 0.143 mg/kg (0.120, 0.162 mg/kg), ED₉₅ = 0.176 mg/kg (0.159, 0.320 mg/kg), and ED₉₉ = 0.189 mg/kg (0.167, 0.394 mg/kg). The esketamine dose and VRS score during propofol injection were significantly different between the two groups (P < 0.05), whereas surgical duration, emergence time, visual analogue scale (VAS) score of postoperative uterine contraction pain, and Riker sedation/anxiety scale (SAS) score were not significantly different. Bradycardia occurred in only one patient during anesthesia induction, while hemodynamics was stable in the rest of the patients without obvious adverse reactions.

CONCLUSION

Small doses of esketamine combined with propofol can be safely and effectively used for hysteroscopic surgery. We recommended a dose of 0.2 mg/kg IV esketamine before induction of anesthesia to reduce the pain of propofol injection.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2100048951. Date of registration: July 19, 2021.

Impact of the Timing of Rocuronium Injection after Propofol Administration on Temporal Summation of Pain in Gynecologic Laparoscopic Surgery: A Prospective and Controlled Study

Purpose

Temporal summation of pain, which is defined as the perception of greater pain evoked by repetitive painful stimuli, varies among individuals. This study aimed at determining the impact of the timing of rocuronium after induction with propofol on the temporal summation of pain.

Methods

One hundred patients aged 19–60 years underwent gynecologic laparoscopic surgery. Patients were randomly assigned to one of the two groups: group PRi received immediate injections of rocuronium after propofol administration and group PRd received rocuronium injections when the bispectral index score (BIS) decreased to <60 after propofol administration. The grade of rocuronium-induced withdrawal movement (RIWM) according to the timing of propofol injection, the incidence and severity of propofol injection pain (PIP), rescue analgesics, visual analog scale (VAS) score after surgery for postoperative pain, patient-controlled analgesia (PCA) opioid consumption, association between PIP and the grade of RIWM, and associations between PIP, the grade of RIWM, and postoperative pain outcomes were measured.

Results

The differences between the incidence and severity of PIP in the two groups were not significant. The grade of the RIWM in the PRd group was significantly reduced compared with the PRi group. Rescue analgesics, severity for postoperative pain, and PCA opioid consumption were not significant. Correlations between the incidence and severity of PIP and the grade of RIWM were weakly negative. Correlations between the grade of RIWM and pain outcomes were moderately positive, but correlations between the severity for PIP and the postoperative pain outcomes were negligible.

Conclusion

The timing of rocuronium administration after propofol injection played a role in reducing RIWM. The grade of RIWM was significantly related to pain outcomes compared with the severity of PIP. Therefore, delayed rocuronium injection after induction with propofol reduced temporal summation of pain.

Clinical efficacy of 5-hydroxytryptamine 3 receptor antagonists in reducing propofol injection pain, postoperative nausea/vomiting and shivering: A meta-analysis

Objective To investigate the clinical efficacy of 5-hydroxytryptamine 3 (5-HT3) receptor antagonists in reducing propofol injection pain, postoperative nausea/ vomiting, and shivering through pooling the available published data.

Methods Prospective randomized clinical studies relevant to 5-HT3 receptor antagonists in reducing propofol injection pain published before June 2019 were identified from four electronic databases, Pubmed, the Cochrane central register of controlled trials, EMBASE and Wanfang. The incidence of propofol injection pain, postoperative nausea/vomiting, and shivering in patients after 5-HT3 receptor antagonists were compared to relevant control groups by pooling the individual data through random or fixed-effect models. The publication bias was assessed by funnel plot and Egger’s line regression test.

Results After screening, a total of 19 publications relevant to 5-HT3 receptor antagonists in reducing propofol injection pain and prevention of postoperative nausea/vomiting or shivering were included for analysis. The pooled results demonstrated that 5-HT3 receptor antagonists could significantly reduce the total propofol injection pain compared to placebo (RR=0.49, 95%CI:0.45-0.54, P<0.05). For mild propofol injection pain, there was no statistical difference between 5-HT3 receptor antagonists and control groups (RR=1.07,95%CI:0.89-1.29, P>0.05). However, for moderate (RR=0.37, 95%CI: 0.31-0.46, P<0.05) and severe (RR=0.19, 95%CI:0.14-0.27, P<0.05) propofol injection pain, the incidence in 5-HT3 receptor antagonists was significantly lower than that of control groups. The pooled results also indicated that incidence of postoperative nausea/vomiting (RR=0.28, 95%CI:0.17-0.44, P<0.05) and postoperative shivering (RR=0.33, 95%CI:0.23-0.48, P<0.05) were significantly reduced in 5-HT3 receptor antagonists group compared to control group with a statistical difference.

Conclusion: In this meta-analysis, 5-HT3 receptor antagonists effectively reduced propofol injection pain, postoperative nausea/vomiting, and shivering.