Can central antiemetic effects of opioids counter-balance opioid-induced nausea and vomiting?

Impacts of Ultrasound-Guided Nerve Block Combined with General Anesthesia with Laryngeal Mask on the Patients with Lower Extremity Fractures

Objective

Surgical reduction is the leading approach to patients with lower extremity fractures. The options of anesthetic drugs during surgery are of great significance to postoperative recovery of patients. There is no consensus on the optimum anesthesia method for patients undergoing lower extremity fracture surgery. Our study is aimed at investigating the impacts of nerve block combined with general anesthesia on perioperative outcomes of the patients.

Methods

In this retrospective study, 48 patients experienced general anesthesia only, and 42 patients received never block combined with general anesthesia. The perioperative hemodynamics was recorded, including mean arterial pressure (MAP), oxygen saturation of blood (SpO2), and heart rate (HR). Visual analogue scale (VAS) and Montreal Cognitive Assessment (MoCA) were carried out to evaluate postoperative pain and cognitive status. Furthermore, adverse reactions and recovery condition were observed between the patients receiving different anesthesia methods.

Results

At 15 minutes and 30 minutes after anesthesia, as well as 5 minutes after surgery, significant lower MAP was observed in the patients treated with general anesthesia (83.04 ± 8.661, 79.17 ± 9.427, 86.58 ± 8.913) compared to those receiving never block combined with general anesthesia (90.43 ± 4.618, 88.74 ± 6.224, 92.21 ± 4.015) (P < 0.05), and compared with general anesthesia group (68.5 ± 7.05, 69.63 ± 7.956, 72.75 ± 8.446), the combined anesthesia group (73.52 ± 9.451, 74.17 ± 10.13, 77.62 ± 9.768) showed obvious higher HR (P < 0.05). No significant difference in SpO2 was found between the two groups at multiple time points (P > 0.05). As for the score of VAS and MoCA, remarkably lower VAS and higher MoCA at 6 h, 12 h and 24 h after surgery were presented in the combined anesthesia group compared to general anesthesia group (P < 0.05). At 24 h after surgery, the two groups showed normal cognitive function (26.33 ± 0.7244 vs. 28.55 ± 0.7392). Incidence of nausea and vomiting in the combined anesthesia group was lower than that of the general anesthesia group (P < 0.05). The time to out-of-bed activity and hospital stay were shorter in the combined anesthesia group compared with general anesthesia (P < 0.05).

Conclusion

The application of never block combined with general anesthesia contributed to the stability of hemodynamics, alleviation of postoperative pain and cognitive impairment, along with decrease in adverse reactions and hospital stay in the patients with lower extremity fractures.

Physiology, signaling, and pharmacology of opioid receptors and their ligands in the gastrointestinal tract: current concepts and future perspectives

Opioid receptors are widely distributed in the human body and are crucially involved in numerous physiological processes. These include pain signaling in the central and the peripheral nervous system, reproduction, growth, respiration, and immunological response. Opioid receptors additionally play a major role in the gastrointestinal (GI) tract in physiological and pathophysiological conditions. This review discusses the physiology and pharmacology of the opioid system in the GI tract. We additionally focus on GI disorders and malfunctions, where pathophysiology involves the endogenous opioid system, such as opioid-induced bowel dysfunction, opioid-induced constipation or abdominal pain. Based on recent reports in the field of pharmacology and medicinal chemistry, we will also discuss the opportunities of targeting the opioid system, suggesting future treatment options for functional disorders and inflammatory states of the GI tract.

[Postoperative nausea and vomiting and opioid-induced nausea and vomiting: guidelines for prevention and treatment]

Postoperative nausea and vomiting (PONV) causes patient discomfort, lowers patient satisfaction, and increases care requirements. Opioid-induced nausea and vomiting (OINV) may also occur if opioids are used to treat postoperative pain. These guidelines aim to provide recommendations for the prevention and treatment of both problems. A working group was established in accordance with the charter of the Sociedad Española de Anestesiología y Reanimación. The group undertook the critical appraisal of articles relevant to the management of PONV and OINV in adults and children early and late in the perioperative period. Discussions led to recommendations, summarized as follows: 1) Risk for PONV should be assessed in all patients undergoing surgery; 2 easy-to-use scales are useful for risk assessment: the Apfel scale for adults and the Eberhart scale for children. 2) Measures to reduce baseline risk should be used for adults at moderate or high risk and all children. 3) Pharmacologic prophylaxis with 1 drug is useful for patients at low risk (Apfel or Eberhart 1) who are to receive general anesthesia; patients with higher levels of risk should receive prophylaxis with 2 or more drugs and baseline risk should be reduced (multimodal approach). 4) Dexamethasone, droperidol, and ondansetron (or other setrons) have similar levels of efficacy; drug choice should be made based on individual patient factors. 5) The drug prescribed for treating PONV should preferably be different from the one used for prophylaxis; ondansetron is the most effective drug for treating PONV. 6) Risk for PONV should be assessed before discharge after outpatient surgery or on the ward for hospitalized patients; there is no evidence that late preventive strategies are effective. 7) The drug of choice for preventing OINV is droperidol.