Minimum local anesthetic dose of ropivacaine in real-time ultrasound-guided intraspinal anesthesia for lower extremity surgery: a randomized controlled trial

Observation of Anesthetic Effect of Dexmedetomidine Combined With Intraspinal Anesthesia in Hip Arthroplasty and its Effect on Postoperative Delirium and Stress Response

Objective

To observe the anesthetic effect of dexmedetomidine combined with spinal anesthesia in hip arthroplasty, and to analyze the effects of dexmedetomidine on postoperative stress response, incidence of delirium, immune function and inflammatory indicators.

Methods

A total of 42 patients who underwent hip replacement in our hospital from March 2020 to June 2021 were selected as the research subjects and randomly divided into the control group and the observation group, 21 cases in each group. The control group was given intraspinal anesthesia, and the observation group was given dexmedetomidine on this basis. The onset time and maintenance time of sensory and motor nerve block were recorded. Stress response indexes [cortisol (Cor), blood glucose (Glu), adrenaline (E), noadrenaline (NE)], T lymphocyte subsets (CD3+, CD4+, CD8+, CD4+/CD8+), inflammatory indexes [tumor necrosis factor -α (TNF-α) and interleukin-6 (IL-6)] were detected before and after operation, and the incidence of postoperative delirium in both groups was recorded.

Results

The onset time of sensory nerve block and motor block in the observation group were lower than those in the control group, and the retention time of sensory nerve block and motor nerve block were higher than those in the control group (P < 0.05). After surgery, the levels of Cor, Glu, E and NE in the observation group were lower than those in the control group (P < 0.05). After surgery, the incidence of postoperative delirium in the observation group (4.79%) was lower than that in the control group (28.57%) (P < 0.05). After surgery, the levels of CD3+, CD4+, CD8+, and CD4+/CD8+ in the observation group were higher than those in the control group (P < 0.05). After surgery, the levels of TNF-α and IL-6 in the observation group were lower than those in the control group (P < 0.05).

Conclusion

The combined use of dexmedetomidine and intraspinal anesthesia has good anesthesia effect in hip joint replacement, which can greatly reduce the stress response of patients, reduce the incidence of postoperative delirium, and effectively restore the immune function of patients, reduce the level of inflammatory response, and has high clinical application value.

Spiral Computed Tomography Imaging Analysis of Positioning of Lumbar Spinal Nerve Anesthesia under the Concept of Enhanced Recovery after Surgery

The objective of this research was to explore the effect of perioperative anesthesia management for patients based on the concept of enhanced recovery after surgery (ERAS) and the application value of the computed tomography (CT) localization method in lumbar spinal nerve anesthesia, reducing the damage caused by anesthesia. One hundred and twenty patients who underwent the lumbar spinal anesthesia in lower limb surgery were selected as the research subjects. According to puncture positioning and nursing intention, the patients were classified into the control group with 30 patients (method of anatomical landmarks), CT group with 50 patients (the CT localization), and ERAS group with 40 patients (the CT localization and the ERAS management). The effects of the anesthesia positioning method and the ERAS management were compared and analyzed. The results showed that d (0.32) and r (0.27) of exponential filtering function were notably smaller than those of R-L filtering function (d = 0.40, r = 0.39) and of S-R filtering function (d = 0.37, r = 0.36) (P < 0.05). Puncture time ((9.23 ± 0.32) min vs. (13.11 ± 0.45) min), puncture direction change (20% vs. 33.33%), abnormal puncture sensation (22% vs. 40%), and nerve root touch (4% vs. 23.33%) in the CT group were all lower than those in the control group. The proportion of Degree I anesthesia effect (94%) of the CT group was greatly higher than that of the control group (76.67%) (P < 0.05). The VAS score, time of activity and gastrointestinal function recovery, and the incidence of adverse reactions (2.5% vs. 28%) in the ERAS group were lower than those in the CT group (P < 0.05). All in all, the CT localization method can improve the difficulty of anesthesia puncture and improve the anesthetic effect; the ERAS nursing concept can improve the postoperative pain of patients and contribute to the prognosis of patients and have a good clinical value.

Comparing the minimum local anesthetic dose of ropivacaine in real-time ultrasound-guided spinal anesthesia and traditional landmark-guided spinal anesthesia: a randomized controlled trial of knee surgery patients

Background

Through previous studies and clinical practice, we have found that real-time ultrasound-guided (UG) spinal anesthesia (SA) and traditional landmark-guided (LG) SA each require a different minimum local anesthetic dose (MLAD) of ropivacaine. For this study, we used Dixon’s up-and-down sequential method to analyze and compare the MLAD of different ropivacaine concentrations required for the UG and LG SA methods.

Methods

A total of 120 patients undergoing knee surgery were consecutively recruited and randomly divided into four groups (30 patients per group). These groups were categorized as follows: Group I: high ropivacaine ultrasound-guided (HRUG), Group II: low ropivacaine ultrasound-guided (LRUG), Group III: high ropivacaine landmark-guided (HRLG), and Group IV: low ropivacaine landmark-guided (LRLG). SA was established by a bolus administration of up-and-down doses of 0.75% or 0.5% plain ropivacaine. Initial doses of 16, 18, 12, and 14 mg were administered to groups I–IV, and after that, increased or decreased by 1.5 mg according to dose effectiveness. Upon identifying the intervertebral puncture level, a lumbar X-ray was performed with metal markers, and actual radiographic findings were identified and compared to the initial markings.

Results

For UG groups, the MLAD in the LRUG group was significantly higher than in the HRUG group [20.192 mg (95% CI, 19.256–21.174) versus 17.176 mg (95% CI, 16.276–18.124), respectively; P<0.001]. For LG groups, the MLAD in the LRLG group was significantly higher than in the HLRG group [14.478 mg (95% CI, 13.364–15.500) versus 13.201 mg (95% CI, 11.959–14.571), respectively; P=0.047]. When comparing both high ropivacaine groups (HRGs: I/III) to the low ropivacaine groups (LRGs: II/IV), we found that both UG subgroups (I/II) had a significantly higher MLAD than LG subgroups (III/IV) (P<0.001). US identified L4–5 in up to 90% of cases. Comparatively, palpation was successful in only 33.3% of patients. The rates of cephalad localization by US and palpation were 6.67% vs. 66.67%, respectively (P=0.002).

Conclusions

We found a higher MLAD of ropivacaine was required for UG SA at the L4–5 level due to the method providing a more accurate (less cephalad) localization than traditional LG SA.

Trial Registration

Chinese Clinical Trial Registry ChiCTR2000033158.