Efficacy and safety of low-dose esketamine for painless gastrointestinal endoscopy in adults: a systematic evaluation and meta-analysis.

Object: The benefits of low-dose esketamine for painless gastrointestinal endoscopy remain unclear. As such, the present study aimed to investigate the efficacy and safety of low-dose esketamine for this procedure. Methods: Seven common databases were searched for clinical studies investigating low-dose esketamine for painless gastrointestinal endoscopy. Subsequently, a meta-analysis was performed to synthesize and analyze the data extracted from studies fulfilling the inclusion criteria. Results: Meta-analysis revealed that, compared with propofol, low-dose esketamine in combination with propofol significantly reduced recovery time by 0.56 min (mean difference [MD] -0.56%, 95% confidence interval (CI) -1.08 to -0.05, p = 0.03), induction time by 9.84 s (MD -9.84, 95% CI -12.93 to -6.75, p < 0.00001), propofol dosage by 51.05 mg (MD -51.05, 95% CI -81.53 to -20.57, p = 0.01), and increased mean arterial pressure by 6.23 mmHg (MD 6.23, 95% CI 1.37 to 11.08, p = 0.01). Meanwhile, low-dose esketamine reduced injection pain by 63% (relative risk [RR] 0.37, 95% CI 0.28 to 0.49, p < 0.00001), involuntary movements by 40% (RR 0.60, 95% Cl 0.42 to 0.85, p < 0.005), choking by 42% (RR 0.58, 95% Cl 0.38 to 0.88, p = 0.01), bradycardia by 68% (RR 0.32, 95% Cl 0.18 to 0.58, p = 0.0002), hypotension by 71% (RR 0.29, 95% Cl 0.21 to 0.40, p < 0.00001), respiratory depression by 63% (RR 0.37, 95% 0.26 to 0.51, p < 0.00001), additional cases of propofol by 53% (RR 0.47, 95% Cl 0.29 to 0.77, p = 0.002), and increased hypertension by 1000% (RR 11.00, 95% Cl 1.45 to 83.28, p = 0.02). There were no significant differences in mean heart rate, mean oximetry saturation, delirium, dizziness, vomiting, tachycardia, and hypoxemia. Subgroup analyses revealed that, compared with other dose groups, 0.25 mg/kg esketamine afforded additional benefits in recovery and induction time, mean arterial pressure, involuntary movements, hypoxemia, and respiratory depression. Conclusion: Low-dose esketamine was found to be safe and effective for providing anesthesia during gastrointestinal endoscopy, with 0.25 mg/kg identified as the optimal dose within the dosage ranges examined. However, caution should be exercised when administering this drug to patients with inadequate preoperative blood pressure control.

[Effects of hydrogen sulfide preconditioning on myocardial ischemia reperfusion injury in rats].

OBJECTIVE: To investigate the effects of hydrogen sulfide preconditioning on myocardial ischemia reperfusion injury in rats. METHODS: Sprague-Dawley male rats were divided into 4 groups with 10 in each group: in S group rats received sham operation; in IR group rats were given with NS (1.0 ml/kg iv) 24 h before ischemia; in H group rats were treated with NaHS (0.05 mg/kg iv) 24 h before ischemia; and in D group, NaHS-treated rats received 5-hydroxydecanoate (5-HD) 15 min before ischemia. Rats in IR group,H group and D group were subjected to ischemia by occlusion of coronary artery for 30 min followed by 2 h of reperfusion. At the end of the reperfusion,myocardial infarct size was measured. SAM-s was measured by Western blotting. Plasma SOD activity and MDA were determined at the end of reperfusion. RESULTS: The infarct size was significantly lesser in H group (25.40 % ± 3.54%) than that in IR group (38.27% ±5.64%,P<0.05). The SAM-s protein expression in myocardium was significantly lower in H group than that in IR group. The plasma MDA content was significantly lower and SOD activity was higher in H group than those in IR group,but there was no difference between IR group and D group. CONCLUSION: The hydrogen sulfide preconditioning attenuates myocardial IR injury possibly through down-regulating SAM-s expression,reducing the production of oxygen free radicals and enhancing anti-oxidize effect in rats.

[Proteomics analysis of myocardium after delayed preconditioning with hydrogen sulfide in rat].

OBJECTIVE: To investigate the changes in protein of myocardium after hydrogen sulfide delayed preconditioning by using proteomics technology. METHODS: Sixteen Sprague-Dawley rats were randomly assigned to control (group S) or hydrogen sulfide group (group H), n = 8 for each group. Myocardial ischemia/reperfusion injury model (ischemia 30 minutes followed by reperfusion 120 minutes) was reproduced at 24 hours after preconditioning either with normal saline or hydrogen sulfide for proteomics analysis in group S or group H, and the myocardial tissue was harvested. The total proteins were extracted and separated by two dimensional gel electrophoresis (2-DE), and the differential protein expression spots were analyzed with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). RESULTS: Analysis of 2-DE showed that 929 ± 14 protein spots were found in group S and 906 ± 10 protein spots in group H, and the expression of 15 protein spots was different between two groups. These protein spots were chosen to undergo MALDI-TOF-MS analysis, and 11 proteins were preliminarily identified, including DNA ligase, cystathionine gamma-lyase, transcription initiation factor, NADH dehydrogenase, guanine nucleotide-releasing factor, fructose-bisphosphate aldolase A, glycogen synthase kinase-3, electron transfer flavoprotein subunit beta, glutathione S-transferase, soluble calcium-activated nucleotidase and S-adenosylmethionine synthetase. CONCLUSIONS: Hydrogen sulfide delayed preconditioning of myocardium resulted in the changes in protein expression profiles in the myocardium. The differential proteins might function as anti-oxidants, to improve the energy metabolism of myocardium, confer cytoprotection and protection of respiratory chain, thus conferring cardioprotection.

[Effect of hydrogen sulfide-induced delayed preconditioning on glutathione S-transferase expression during myocardial ischemia-reperfusion in rats].

OBJECTIVE: To investigate the effect of hydrogen sulfide-induced delayed preconditioning on glutathione S-transferase (GST) expression during myocardial ischemia-reperfusion in rats. METHODS: Sprague-Dawley male rats were randomly divided into 4 groups (n= 10 in each): Group S (sham operation group), Group IR (ischemia/reperfusion group), Group H (IR+ NaHS 0.05 mg/kg iv, 24 h before ischemia) and Groups D receiving IR+NaHS 24 h before ischemia and 5-hydroxydecanoate (5-HD)15 min before ischemia. Animals in groups IR, H and D were subjected to ischemia by 30 min of coronary artery occlusion followed by 2 h of reperfusion. At the end of the reperfusion, myocardial infarct size (IS) was examined. Glutathione S-transferase (GST) was measured by Western blotting. The myocardial ultrastructures were observed under the electron microscopy. RESULTS: The IS was significantly smaller in Group H than that in Group IR [(25.40 ± 3.54)% compared with (38.27 ± 5.64)%, P<0.05]. The GST expression in myocardium was significantly higher in Group H than that in Group IR. Microscopic examination showed less myocardial damage in Group H than in Group IR. The protective effects of delayed preconditioning by hydrogen sulfide was prevented by 5-HD pre-treatment. CONCLUSION: The hydrogen sulfide-induced delayed preconditioning attenuates myocardial IR injury possibly through up-regulating glutathione S-transferase expression in rats.