Synergistic antinociceptive effects of alfentanil and propofol in the formalin test

Comparison of anesthetic effects of different doses of alfentanil combined with ciprofol in elderly patients undergoing ERCP: a randomized controlled trial

BACKGROUND AND OBJECTS

Patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) are often old and poor in physical fitness. The purpose of this study was to investigate the anesthetic effect of different doses of alfentanil combined with ciprofol in elderly patients undergoing endoscopic retrograde cholangiopancreatography (ERCP).

METHODS

In this clinical trial, 137 patients, who were candidates for ERCP were randomly divided into three groups. Group A were given 0.15 μg/kg/min of alfentanil in maintenance stage, Group B were given 0.25 μg/kg/min and Group C were given 0.35 μg/kg/min. Mean arterial pressure (MAP), heart rate (HR), oxygen saturation (SpO2) of the patients at each time point including the entry into the operation room (T0), at the beginning of surgery(T1), 10 min after surgery(T2), 20 min after surgery(T3), 30 min after surgery(T4),endoscopy withdrawal (T5) were recorded. Adverse events(including respiratory depression, body movement and hypoxemia),the dosage of ciprofol, the time of operation time and awakening were recorded.

RESULTS

Compared with Group A, MAP and HR in Group B and Group C was decreased during T1-T5 (P < 0.05). Compared with group B, MAP and HR in group C was decreased during T1-T5 (P < 0.05). Compared with Group A and Group C,the number of adverse reactions of Group B was decreased(P < 0.05). There was no statistical difference in surgical time among the three groups(P > 0.05),but a statistically significant difference in recovery time (P < 0.05).

CONCLUSION

The adverse events of alfentanil 0.25μg/kg/min combined with ciprofol were low, and the anesthetic effect was the best.

Efficacy and safety of alfentanil plus propofol versus propofol only in painless gastrointestinal endoscopy: A meta-analysis

BACKGROUND

To systematically evaluate the efficacy and safety of alfentanil plus propofol versus propofol only for painless gastrointestinal endoscopy.

METHODS

The Cochrane Library, PubMed, Embase, China Biology Medicine, CNKI, WanFang, and VIP databases were searched to identify randomized controlled trials on alfentanil combined with propofol versus propofol only for painless gastrointestinal endoscopy from the inception of the database to August 2022. The Rev Man 5.4 software was used for statistical analyses.

RESULTS

Thirteen randomized controlled trials involving 1762 patients were identified as eligible for this study. The meta-analysis showed that compared with propofol, alfentanil combined with propofol had a more stable mean arterial pressure [mean difference (MD) = 5.38, 95% confidence interval (CI): 1.97-8.80; P = .002], heart rate (MD = 3.78, 95% CI: 1.30-6.26; P = .003) and pulse oxygen saturation (MD = 1.90, 95% CI: 0.93-2.78; P = .0001); a lower propofol dose (standard mean difference = -2.82, 95% CI: -3.70 to -1.94; P < .00001), lower awakening time (MD = -3.23, 95% CI: -4.01 to -2.45; P < .00001) and lower directional force recovery time (MD = -3.62, 95% CI: -4.22 to -3.03; P < .00001); a lower incidence of nausea and vomiting (relative risk [RR] = 0.32, 95% CI: 0.14-0.71; P = .005), body movement (RR = 0.27, 95% CI: 0.13-0.54; P = .0002), hypotension (RR = 0.23, 95% CI: 0.12-0.46; P < .0001), respiratory depression (RR = 0.37, 95% CI: 0.15-0.89; P = .03) and cough reflex (RR = 0.33, 95% CI: 0.12-0.89; P = .03).

CONCLUSION

This meta-study found that current evidence indicates that alfentanil plus propofol is better than propofol alone for painless gastrointestinal endoscopy and is associated with a lower incidence of adverse reactions. Due to the limited quality and quantity of the included studies, more high-quality studies are needed to validate these above conclusions.

Synergistic interaction between DAMGO-NH2 and NOP01 in peripherally acting antinociception in two mouse models of formalin pain

The most commonly used opioid analgesics are limited by their severe side-effects in the clinical treatment of pain. Preliminary reports indicate that the combination of classical opioids and N/OFQ receptor (NOP) ligands may be an effective strategy to reduce unwanted side-effects and improve antinociception. But the interaction of these two receptor ligands in pain regulation at the peripheral level remains unclear. In this study, the antinociception of a designed amide analogue of the mu opioid receptor (MOP) peptide agonist DAMGO, DAMGO-NH₂, and its antinociceptive interaction with the peripherally limited NOP peptide agonist NOP01 was investigated in two mouse models of formalin pain. Our results showed that DAMGO-NH₂ acted as a MOP agonist in in vitro functional assays. Moreover, local subcutaneous or intraplantar injection of DAMGO-NH₂ exerted dose-related antinociception in both phases of the formalin orofacial and intraplantar pain, which could be mediated by the classical opioid receptor. Peripheral but not central pretreatment with the peripherally restricted opioid antagonist naloxone methiodide inhibited local DAMGO-NH₂-induced antinociception, supporting the involvement of the peripheral opioid receptor in local DAMGO-NH₂-induced antinociception. Furthermore, co-administration of the inactive doses of DAMGO-NH₂ and NOP01 produced effective antinociception. More importantly, isobolographic analysis indicates that the combination of DAMGO-NH₂ and NOP01 elicited supra-additive antinociception in these two models of formalin pain. In addition, the combination of DAMGO-NH₂ and NOP01 did not change motor function of mice in rotarod test. In conclusion, these data suggest that peripheral DAMGO-NH₂ and particularly its combination therapy with NOP01 may be effective for pain management.

Isobolographic analysis of the antidepressant interaction in two-drug combinations of citalopram, bupropion, and scopolamine in mice

Depression and anxiety are psychiatric diseases that commonly occur together, and the patient burden and complexity increase when both are present. Comorbid anxiety and depression are often more resistant to common drug treatments such as antidepressants. Combination therapy is a suggested approach in treating these patients, where a decline of doses could reduce undesirable outcomes and still achieve optimal effects. We, therefore, conducted a preclinical study to assess the effect of two-drug combinations of citalopram, bupropion, and scopolamine on anxiety- and antidepressive-like behaviors in male NMRI mice and aimed to determine the nature of the interaction between components. Anxiety- or antidepressive-like activity of mice was assessed by the hole-board or forced swim test (FST), respectively. Our results revealed that citalopram (0.01-0.25 mg/kg; i.p.), bupropion (1-9 mg/kg; i.p.), or scopolamine (0.01-0.1 mg/kg; i.p.) diminished immobility time in the FST, suggesting an antidepressive-like effect. Citalopram decreased dead-dip counts in the hole-board, indicating an anxiogenic-like activity. All two-drug combinations, at inactive doses, exerted an antidepressive-like behavior. Only bupropion/scopolamine combination increased head-dip counts compared to the bupropion/saline group. Isobolographic analysis revealed an antidepressive synergy effect between citalopram plus bupropion, and an antidepressive additive impact between scopolamine plus citalopram or bupropion. It should be noted that the higher dose of each drug alone declined locomotor activity, while two-drug combinations did not affect this parameter. These results suggest a stronger antidepressive effect for citalopram/bupropion combination than other two-drug combinations.