The effect of midazolam or lidocaine administration prior to etomidate induction of anesthesia on heart rate, arterial pressure, intraocular pressure and serum cortisol concentration in healthy dogs

Exploring separation mechanisms and lipophilicity in hydrophilic interaction chromatography conditions by thin-layer chromatography of anesthetics and adjuvant drugs as polar model compounds

The chromatographic behavior of the selected compounds was studied under conditions of hydrophilic interaction liquid chromatography (HILIC). The effect of mobile phase composition on the retention in different chromatographic systems was systematically examined using high-performance thin-layer chromatography. The sorbents of different polarity and adsorption characteristics were selected and mixtures of water and organic solvents of various compositions, from pure water to pure organic solvent were used as mobile phases. Increasing the amount of water in the mobile phase leads to a conversion of the separation mechanism, and the retention curves have a characteristic "U" shape. The conversion between the adsorption and partition mechanisms is most likely continuous and depends on the chemical nature of separated substances, the stationary phase as well as on organic component of the mobile phase. Silica gel can be considered the most suitable stationary phase for the systematic investigation of the chromatographic behavior of the test compounds, whereas acetonitrile was the most suitable solvent. The obtained results contribute to the understanding of the dominant separation mechanism, the type, and the intensity of the interactions between separated substances with both stationary and mobile phases. Besides, the lipophilicity parameters obtained under HILIC conditions were evaluated and correlated with the calculated values.

Heart rate, arterial pressure and propofol-sparing effects of guaifenesin in dogs

OBJECTIVE

To evaluate the heart rate (HR) and systemic arterial pressure (sAP) effects, and propofol induction dose requirements in healthy dogs administered propofol with or without guaifenesin for the induction of anesthesia.

STUDY DESIGN

Prospective blinded crossover experimental study.

ANIMALS

A total of 10 healthy adult female Beagle dogs.

METHODS

Dogs were premedicated with intravenous (IV) butorphanol (0.4 mg kg^-1) and administered guaifenesin 5% at 50 mg kg^-1 (treatment G50), 100 mg kg^-1 (treatment G100) or saline (treatment saline) IV prior to anesthetic induction with propofol. HR, invasive sAP and respiratory rate (f_R) were recorded after butorphanol administration, after guaifenesin administration and after propofol and endotracheal intubation. Propofol doses for intubation were recorded. Repeated measures analysis of variance (anova) was used to determine differences in propofol dose requirements among treatments, and differences in cardiopulmonary values over time and among treatments with p < 0.05 considered statistically significant.

RESULTS

Propofol doses (mean ± standard deviation) for treatments saline, G50 and G100 were 3.3 ± 1.0, 2.7 ± 0.7 and 2.1 ± 0.8 mg kg^-1, respectively. Propofol administered was significantly lower in treatment G100 than in treatment saline (p = 0.04). In treatments G50 and G100, HR increased following induction of anesthesia and intubation compared with baseline measurements. HR was higher in treatment G100 than in treatments G50 and saline following induction of anesthesia. In all treatments, sAP decreased following intubation compared with baseline values. There were no significant differences in sAP among treatments. f_R was lower following intubation than baseline and post co-induction values and did not differ significantly among treatments.

CONCLUSIONS AND CLINICAL RELEVANCE

When administered as a co-induction agent in dogs, guaifenesin reduced propofol requirements for tracheal intubation. HR increased and sAP and f_R decreased, but mean values remained clinically acceptable.

Etomidate Alleviates Ischemia-Anoxia Reperfusion Injury in Intestinal Epithelial Cells by Inhibiting the Activation of traf6-Regulated NF-KB Signaling

Objective: The present study aimed to investigate the role of etomidate in intestinal cell ischemia and hypoxia-reperfusion injury and potential mechanisms. Method: In this study, we establish the intestinal epithelial cells ischemia-reperfusion model in vitro. CCK8 was used to detect cell viability and flow cytometry assay was used to detect apoptosis levels of treated OGD/R model cells. ELISA measured the expression level of oxidative stress factors and inflammatory factors. Furthermore, western blot assay was used to detect the expression the apoptosis-related factors and TNFR-associated factors in treated OGD/R model cells. Result: Etomidate does not affect the activity of intestinal epithelial cells, and can protect intestinal epithelial cells to reduce ischemiareperfusion injury, and the expression of inflammatory factors and oxidative stress in cells with mild intestinal epithelial ischemia-reperfusion injury. Etomidate alleviates apoptosis of intestinal epithelial ischemia-reperfusion injury cells. Etomidate inhibits the activation of traf6-mediated NF-κB signal during ischemia-anoxia reperfusion of intestinal epithelial cells. Conclusion: Taken together, our study demonstrated that etomidate attenuates inflammatory response and apoptosis in intestinal epithelial cells during ischemic hypoxia-reperfusion injury and inhibits activation of NF-κB signaling regulated by TRAF6.

Effect of Stellate Ganglion Block Combined with Lidocaine at Different Concentrations for Preemptive Analgesia on Postoperative Pain Relief and Adverse Reactions of Patients Undergoing Laparoscopic Cholecystectomy

Objective

To explore the effect of stellate ganglion block (SGB) combined with lidocaine at different concentrations for preemptive analgesia on postoperative pain relief and adverse reactions of patients undergoing laparoscopic cholecystectomy (LC).

Methods

Ninety patients undergoing LC in our hospital from June 2019 to June 2020 were selected as the subjects and were randomly divided into group A (30 cases), group B (30 cases), and group C (30 cases), all patients received SGB, and 10 mL of lidocaine at concentrations of 0.25%, 0.5%, and 0.75% was, respectively, administered to patients in groups A, B, and C, so as to compare the analgesic effect, adverse reactions, and clinical indicators among the three groups.

Results

At T₁ and T₂, group C obtained obviously lower NRS scores than groups A and B (P < 0.001); compared with groups A and B, group A had obviously higher onset time (P < 0.001) and significantly lower duration (P < 0.001); no obvious differences in the hemodynamic indexes among the groups were observed (P > 0.05); group C obtained obviously higher BCS score than groups A and B; and the total incidence rate of adverse reactions was obviously higher in group C than in groups A and B (P < 0.05).

Conclusion

Performing SGB combined with 0.5% lidocaine to patients undergoing LC achieves the optimal analgesic effect; such anesthesia plan can effectively stabilize patients' hemodynamics, present higher safety, and promote the regulation of the body internal environment. Further research will be conducive to establishing a better anesthesia plan for such patients.

Descriptive assessment of adverse events associated with midazolam-etomidate versus saline-etomidate in healthy hydromorphone premedicated dogs

OBJECTIVES

To determine the frequency, severity and duration of adverse events including myoclonus, pain on injection, hypersalivation, regurgitation and apnoea after administration of midazolam or saline followed by etomidate in hydromorphone premedicated dogs.

MATERIALS AND METHODS

Dogs undergoing elective dental prophylaxis or soft tissue surgeries were enrolled in this randomised trial. Dogs were premedicated with hydromorphone 0.1 mg/kg IV. Sixty seconds later, midazolam 0.3 mg/kg or saline at an equivalent volume was administered IV. Sixty seconds after that, etomidate 1.5 mg/kg IV was administered over 60 seconds. Additional doses of 0.5 mg/kg etomidate were administered until endotracheal intubation was successful. Observers were blinded to the treatment. Frequency, duration and a severity score of 0 to 3 were recorded for myoclonus, pain on injection, hypersalivation and regurgitation. Duration of apnoea and frequency of any additional complications was recorded.

RESULTS

Forty variable breed healthy dogs were enrolled in the study. Myoclonus, pain on injection, regurgitation, hypersalivation, gagging, tachypnoea and pigmenturia occurred, respectively, in 10%, 40%, 0%, 15%, 35%, 25% and 5% of dogs in the saline group and 0%, 65%, 0%, 10%, 45%, 15% and 5% of dogs in the midazolam group. Apnoea occurred for 115 seconds (range 0 to 660 seconds) and 160 seconds (range 0 to 600 seconds) in the saline and midazolam groups, respectively. Two dogs developed pigmenturia. The trial was stopped early due to the occurrence of pigmenturia.

CLINICAL SIGNIFICANCE

Due to early stopping of the trial, the predefined sample size was not reached. Further investigation is needed to determine if midazolam reduced the incidence of adverse events or improved the induction quality when combined with hydromorphone and etomidate.