Dexmedetomidine as an adjunct to local anesthetics in nerve block relieved pain more effectively after TKA: a meta-analysis of randomized controlled trials

Frailty: the perioperative and anesthesia challenges of an emerging pandemic

Frailty is a complex and multisystem biological process characterized by reductions in physiological reserve. It is an increasingly common phenomena in the surgical population, and significantly impacts postoperative recovery. In this review, we will discuss the pathophysiology of frailty, as well as preoperative, intraoperative, and postoperative considerations for frailty care. We will also discuss the different models of postoperative care, including enhanced recovery pathways, as well as elective critical care admission. With discoveries of new effective interventions, and advances in healthcare information technology, optimized pathways could be developed to provide the best care possible that meets the challenges of perioperative frailty.

Dexmedetomidine protects against Ropivacaine-induced neuronal pyroptosis via the Nrf2/HO-1 pathway

Dexmedetomidine (DEX) has been demonstrated to protect against ropivacaine (Ropi)-induced neuronal damages. This study was conducted to explore the protective role of DEX in Ropi-induced neuronal pyroptosis and provide a strategy to eliminate Ropi-induced neurotoxicity. The impacts of different concentrations of Ropi and DEX on neurotoxicity in SK-N-SH cells were evaluated by cell counting kit-8 assay and lactic dehydrogenase assay kits. Levels of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), NLR family pyrin domain containing 3 (NLRP3), cleaved Caspase-1, cleaved N-terminal gasdermin D, interleukin (IL)-1β, and IL-18 were measured by real-time quantitative PCR, Western blotting, and enzyme linked immunosorbent assay. The Nrf2 level after nuclear/cytoplasmic separation was quantified. SK-N-SH cells were treated with si-Nrf2, Nigericin (NLRP3 activator), and Zinc Protoporphyrin (HO-1 inhibitor) to validate the mechanism. Ropi reduced SK-N-SH cell viability in a concentration- and time-dependent manner. DEX treatment alleviated Ropi-induced toxicity and inhibited pyroptosis. Ropi increased the expression levels of Nrf2 and HO-1, and DEX further enhanced the increases and promoted Nrf2 nuclear translocation. Nrf2/HO-1 inhibition or NLRP3 activation both neutralized the inhibitory role of DEX in Ropi-induced pyroptosis of SK-N-SH cells. Overall, DEX promoted the Nrf2/HO-1 pathway to inhibit NLRP3 expression, thus alleviating Ropi-induced neuronal pyroptosis.

Does dexmedetomidine combined with levobupivacaine in inferior alveolar nerve blocks among patients undergoing impacted third molar surgery control postoperative morbidity?

Background

Postoperative analgesia (POA) is an important determinant of successful treatment. Dexmedetomidine (DEX) has recently gained attention as a promising adjuvant to local anesthetics (LA). The present study aimed to evaluate the efficacy and safety of levobupivacaine (LB) as an adjuvant during inferior alveolar nerve block (IANB) in the extraction of lower impacted third molars (LITM).

Methods

A prospective, randomized, placebo-controlled, triple-blind, parallel-arm, and clinical study was performed on 50 systemically healthy participants who required removal of an asymptomatic LITM. Using a 1:1 distribution, the participants were randomized into two groups (n = 25). Group L (control group) received 1.8 mL of 0.5% LB and 0.2 mL normal saline (placebo) and Group D (study group) received a blend of 1.8 mL of 0.5% LB and 0.2 mL (20 µg) DEX. The primary outcome variable was the duration of POA and hemodynamic stability, and the secondary variable was the total number of analgesics required postoperatively for up to 72 h. The participants were requested to record the time of rescue analgesic use and the total number of rescue analgesics taken. The area under the curve was plotted for the total number of analgesics administered. The pain was evaluated using the visual analog scale. Data analysis was performed using paired students and unpaired t-test, Mann–Whitney U test, Chi-square test, and receiver operating characteristic analysis. Statistical significance was set at P < 0.05.

Results

The latency, profoundness of anesthesia, and duration of POA were statistically significant (P < 0.05). The differences between mean pain scores at 6, 12, 24, 48, and 72 h were found to be significant (each P = 0.0001). Fewer analgesics were required by participants in group D (2.12 ± 0.33) than in L (4.04 ± 0.67), with a significant difference (P = 0.0001).

Conclusion

Perineurally administered LA with DEX is a safe, effective, and therapeutic approach for improving latency, providing profound POA, and reducing the need for postoperative analgesia.

Continuous Lumbar Plexus Block under the Guidance of the "Shamrock Method" Ultrasound: Analgesic Effects and Hemodynamic Effects after Total Knee Arthroplasty in Elderly Patients

Objective

To explore the effect of continuous lumbar plexus block guided by the “Shamrock method” on postoperative analgesia and hemodynamics in elderly patients after total knee arthroplasty (TKA).

Methods

From January 2020 to December 2020 in our hospital, 98 patients who underwent TKA were selected. Using the random number table method, the patients were divided into two groups: a continuous lumbar plexus block group (group L), with 49 patients, and a continuous femoral nerve block group (group F), with 49 patients. The onset time and maintenance time of motor and sensory nerve blocks in patients were recorded. A visual analogue scale (VAS) was applied to assess the pain severity at 6, 12, 24, and 48 h after the operation. The VAS score (FVAS) was applied to evaluate the pain severity of the patients during 24 and 48 h after the operation and knee joint functional exercise. The levels of hemodynamic indexes such as heart rate, mean arterial pressure, and oxyhemoglobin saturation and the levels of hemorheological indexes such as plasma viscosity, high and low whole blood shear viscosity, fibrinogen, and hematocrit were detected and compared between the two groups immediately after the operation and at 12 h and 48 h after the operation, respectively. The incidence of adverse reactions induced by anesthesia was counted.

Results

The onset time of motor and sensory nerve blocks in group L was lower than that in group F, and the maintenance time was higher than that in group F (P < 0.05). The VAS scores of 6, 12, 24, and 48 h after operation in group L were significantly lower than those in group F (P < 0.05). The FVAS scores of group L at 24 and 48 h after operation were significantly lower than those of group F (P < 0.05). The heart rates of the patients in the two groups were higher at 12 h and 48 h after operation than those immediately after operation (P < 0.05). The heart rates at 12 h and 48 h after operation in group L were lower than those in group F (P < 0.05). The plasma viscosity, high whole blood shear viscosity, and low whole blood shear viscosity in the group L at 12 h and 48 h after operation were lower than those in group F (P < 0.05). There was no significant difference in the incidence of local anesthetic poisoning, nausea, vomiting, urinary retention, pruritus, and other adverse reactions between the two groups (P > 0.05).

Conclusion

The “Shamrock method” ultrasound-guided continuous lumbar plexus block in elderly patients after TKA has good analgesic effect, stable hemodynamics, little influence on hemorheology, and good safety. It is of great value to enhance the surgical effect and promote postoperative rehabilitation.