Application of dexmedetomidine-assisted intravertebral anesthesia in hip replacement and its influence on T-lymphocyte subsets

The effect of magnesium sulfate on emergence agitation in surgical adult patients undergoing general anesthesia: A systematic review and meta-analysis of randomized controlled trials

STUDY OBJECTIVE

Investigating the effect of magnesium sulfate (MS) on emergence agitation (EA) in adult surgical patients following general anesthesia (GA).

DESIGN

Systematic literature review and meta-analysis (PROSPERO number: CRD42023461988).

SETTING

Review of published literature.

PATIENTS

Adults undergoing GA.

INTERVENTIONS

Intravenous administration of MS.

MEASUREMENTS

We searched PubMed/MEDLINE, EMBASE, the Cochrane Library, Scopus, and Web of Science for publications until September 14, 2023. The primary outcome was the incidence of EA, while the secondary outcomes included the impact of MS on postoperative agitation score (PAS), emergence variables and adverse events. Relative risk (RR) with 95% confidence interval (CI) measured dichotomous outcome, while standardized mean difference (SMD) or mean difference (MD) with 95% CI measured continuous outcomes.

MAIN RESULTS

Meta-analysis of five randomized controlled trials (RCTs) indicated that MS was associated with a lower incidence of EA at various time points (0 min: RR = 0.62, 95% CI [0.41, 0.95]; p = 0.183, I2 = 43.6%; 5 min: RR = 0.29, 95% CI [0.16, 0.52]; p = 0.211, I2 = 36%; 10 min: RR = 0.14, 95% CI [0.06, 0.32]; p = 0.449, I2 = 0%; 15 min: RR = 0.11, 95% CI [0.02, 0.55]; p = 0.265, I2 = 19.5%; 30 min: RR = 0.05, 95% CI [0.00, 0.91]; the postoperative period: RR = 0.21, 95% CI [0.09, 0.49]; p = 0.724, I2 = 0%;). Additionally, MS was associated with a reduced PAS at various time points except for 0 min. However, no significant differences were observed in extubation time, the length of stay in the post-anesthesia care unit, postoperative nausea and vomiting or total complications.

CONCLUSIONS

Limited available evidence suggests that MS was associated with a lower incidence of EA. Nevertheless, further high-quality studies are warranted to strengthen and validate the effect of MS in preventing EA in adult surgical patients.

Effects of dexmedetomidine on renal function, inflammatory markers, and cognitive functioning in elderly patients undergoing hip replacement surgery

OBJECTIVE

To investigate the effects of dexmedetomidine on renal function, inflammatory markers, and cognitive outcome, and to identify factors influencing early postoperative cognitive dysfunction (POCD) in elderly patients undergoing hip replacement surgery.

METHODS

A retrospective analysis was conducted on 162 elderly patients who underwent hip replacement surgery at Cangzhou Central Hospital from March 2022 to May 2023. Patients were divided into a control group (without dexmedetomidine) and an experimental group (with dexmedetomidine). Measurements included creatinine (Cr), blood urea nitrogen (BUN), interleukin 1β (IL-1β), tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), Montreal Cognitive Assessment (MoCA) score, and the incidence of POCD seven days postoperatively. Univariate and logistic regression analyses were employed to investigate the predictors of early POCD.

RESULTS

Significant differences were observed between the groups in terms of renal function, inflammatory markers, and cognitive outcome (Cr, BUN, IL-1β, TNF-α, IL-6 and MoCA scores) (all P<0.05). The experimental group showed a significantly lower incidence of POCD at seven days post-surgery (P<0.05). Logistic regression identified having a neuron-specific enolase (NSE) level seven days post-surgery ≥7.0 pg/ml as a risk factor for early POCD (P=0.001, OR=3.987, 95% CI: 1.789-8.886), whereas intraoperative use of dexmedetomidine was a protective factor (P=0.041, OR=0.424, 95% CI: 0.187-0.964).

CONCLUSION

The use of dexmedetomidine in hip replacement surgery can mitigate postoperative renal injury and inflammatory response, enhance cognitive outcome, and significantly reduce the incidence and risk of early POCD in elderly patients.

Effects of dexmedetomidine on early postoperative cognitive function and postoperative inflammatory response: a systematic review and network meta-analysis

Background

Dexmedetomidine (DEX) has demonstrated potential as an effective agent for enhancing early postoperative cognitive function. However, there is ongoing debate regarding its optimal dosage and impact on early postoperative inflammatory response. This study aimed to assess and prioritize the effects of varying doses of DEX on early postoperative cognitive function and inflammatory response, in order to identify the most effective intervention dosage.

Methods

Randomised controlled trials (RCTs) and retrospective cohort studies (RCS) from PubMed, Embase, and Cochrane Library up to January 28, 2024, were included. The Mini-Mental State Examination (MMSE) was utilized to assess the impact of varying doses of DEX on cognitive function during the early postoperative period as the primary outcome, peripheral blood levels of IL-6 and TNF-α were considered as secondary outcomes. Meta-analysis and Bayesian Network Meta-Analysis (NMA) were conducted using R. Funnel plots were generated using Stata 15.0.

Results

A total of 29 studies involving 2,807 patients and 25 different doses of DEX were included. DEX was given at a loading dose of 0.3-1.0 μg/kg followed by a maintenance dose of 0.1-0.5 μg/kg/h, or at a uniform intraoperative dose of 0.4-0.7 μg/kg/h. Network meta-analysis revealed most doses of DEX were significantly more effective than normal saline (NS) in improving postoperative MMSE scores (on days 1, 3, and 7) and lowering IL-6 and TNF-α levels. Probability results showed that a 1 μg/kg loading dose followed by a 0.6 μg/kg/h maintenance dose was the best dosing regimen for improving MMSE scores on postoperative days 1 (97.3%), 3 (100%), and 7 (99.9%), as well as for reducing postoperative blood IL-6 levels (1.3%). On the other hand, 0.3 μg/kg followed by 0.2 μg/kg/h was the optimal dosing regimen for reducing postoperative blood TNF-α levels (6.6%).

Conclusion

Compared with NS, intraoperative intravenous DEX improved early postoperative cognitive function and postoperative inflammatory response in patients undergoing elective surgery. In particular, a 1 μg/kg loading dose and a 0.6 μg/kg/h maintenance dose resulted in the best improvement in postoperative MMSE scores and blood IL-6 levels, while a 0.3 μg/kg loading dose followed by a 0.2 μg/kg/h maintenance dose is the optimal regimen for lowering postoperative blood TNF-α levels.Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=433932, identifier CRD42023433932.

Exploring the Potential Role of Dexmedetomidine in Reducing Postoperative Cognitive Dysfunction in Elderly Hip Fracture Patients

BACKGROUND

Hip fractures are prevalent in the elderly; however, Postoperative Cognitive Dysfunction (POCD) is a possible complication of hip fracture surgery in elderly patients. This study examines the influence and the underlying mechanism of dexmedetomidine on POCD in elderly patients following hip fracture surgery.

METHODS

The retrospective study involved elderly patients with hip fracture who were treated at the Fifth Affiliated Hospital of Xinjiang Medical University from October 2021 to August 2022. During the surgery procedures, dexmedetomidine was administrated and the peripheral blood samples were collected from the patients. Inflammatory factors were measured using Enzyme-linked immunosorbent assay (ELISA), while pyroptosis-related proteins were detected through quantitative reverse transcription PCR (RT-qPCR) and western blot. Additionally, the levels of CD4+T and CD8+T cells were assessed using flow cytometry. An aged rats hip fracture model was established to further investigate the impact of dexmedetomidine on postoperative mobility, cognition function, pyroptosis and immune cells in rats.

RESULTS

Postoperative cognitive function in patients did not show significant alteration when compared with pre-operation levels (p > 0.05). There were notable reduction in the levels of interleukin-18 (IL-18), Caspase-3, Gasdermin-D (GSDMD) and NLR Family Pyrin Domain Containing 3 (NLRP3) (p < 0.001), accompanied by an increase in the proportion of CD4+T cells and an decrease in CD8+T cells after operation (p < 0.01). In aged rats, postoperative exploratory activities increased compared to their preoperative state. Compared with preoperative levels, the levels of interleukin-1β (IL-1β), IL-18, Caspase-3, GSDMD, and NLRP3 were significantly decreased (p < 0.001), the proportion of CD4+T cells was increased, and the proportion of CD8+T cells was decreased postoperatively (p < 0.01).

CONCLUSIONS

Although there was no significant alteration in postoperative cognitive function in patients, dexmedetomidine may still play a role in mitigating POCD potentially due to its effects on reducing immune inflammation and pyroptosis markers. Further research is needed to fully understand the underlying mechanisms and its clinical implications.

Effects of dexmedetomidine at different dosages on perioperative haemodynamics and postoperative recovery quality in elderly patients undergoing hip replacement surgery under general anaesthesia: a randomized controlled trial

BACKGROUND

Dexmedetomidine could provide some advantages to prevent postoperative complications in elderly patients undergoing under general anaesthesia. However, dexmedetomidine inhibits haemodynamics to some extent due to its sympathetic inhibition.

OBJECTIVE

To evaluate the effects of different doses of dexmedetomidine on haemodynamics during surgery and recovery after general anaesthesia in elderly patients undergoing hip replacement.

METHODS

This was a prospective randomized double-blind controlled clinical trial. Eligible patients were randomly allocated into comparative groups (normal saline (NS) and midazolam (MD), n = 30) and dexmedetomidine groups at different doses (D0.25/D0.5/D0.75, n = 30). In the D0.25/D0.5/D0.75 groups, dexmedetomidine was administered at different initial loading doses (0.25/0.5/0.75 μg/kg for 15 min) following 0.5 μg/kg/h continuous infusion until the end of the operation. In the MD group, patients were administered 0.03 mg/kg midazolam at the beginning of anaesthesia induction.

RESULTS

Compared to the MD and NS groups, there were significant decreases in MAP in the D0.5 and D0.75 groups at many time points, such as skin incision, end of operation, and from extubation until 30 min after extubation (P < 0.05); there were also significant decreases in HR in the D0.5 and D0.75 groups at time points including anaesthesia induction, end of operation, and from extubation to 2 h after operation (P < 0.05). In the D0.25 group, there were few differences in the changes in MAP and HR compared to the MD and NS groups during the entire perioperative period (P > 0.05). Moreover, the percentage of patients whose MAP and HR decreased > 20% of baseline was higher in the D0.75 and D0.5 groups than that in all other groups. Compared to the NS group, from the beginning to the end of the operation, the 95% confidence interval (CI) of RR for MAP below > 20% of baseline in the D0.5 and D0.75 groups was greater than 1. In particular, the CI of the RR in the D0.75 group was greater than 1 until the patient awoke from general anaesthesia (P < 0.05). In addition, the CI of the RR for HR below > 20% of baseline in the D0.5 group was greater than 1 compared to the NS group at the time of induction and extubation (P < 0.05). There was no significant difference in the possibility of developing hypotension or bradycardia in the MD or D0.25 groups compared to the NS group (P > 0.05). The recovery quality of patients during the post-anaesthesia period was also observed. No differences were observed among all the groups in the time to awakening or extubation after general anaesthesia (P > 0.05). According to the Riker Sedation-agitated Scale, dexmedetomidine significantly alleviated emergency agitation or delirium compared to NS (P < 0.05). In addition, the scores in the D0.5 and D0.75 groups were lower than those in the D0.25 group (P < 0.05).

CONCLUSION

Dexmedetomidine could alleviate the agitation of elderly patients undergoing hip replacement after intravenous general anaesthesia combined with inhaled sevoflurane without delayed recovery. However, it is necessary to be vigilant about the haemodynamic inhibition of the drug at high dosages throughout the perioperative period. Dexmedetomidine 0.25-0.5 μg/kg as the initial loading dose followed by 0.5 μg/kg/h continuous infusion might provide comfortable recovery after general anaesthesia with slight haemodynamic inhibition.

TRAIL REGISTRATION

ClinicalTrial.gov, No. NCT05567523. Registered 05 October 2022, https://clinicaltrials.gov/ct2/show/NCT05567523?term=NCT05567523&draw=2&rank=1 .

Effect of dexmedetomidine on postoperative cognitive dysfunction in elderly patients undergoing orthopaedic surgery: study protocol for a randomized controlled trial

AIMS

This trial aims to assess whether dexmedetomidine can reduce the incidence of postoperative cognitive dysfunction in elderly orthopaedic patients and explore the specific mechanism.

BACKGROUND

Postoperative cognitive dysfunction is a common complication after orthopaedic surgery that results in poor prognosis and increases the length of hospital stays and costs. Dexmedetomidine has been confirmed as a drug that can improve postoperative cognitive dysfunction in some studies. However, to date, the specific mechanism by which dexmedetomidine improves postoperative cognitive dysfunction is still elusive.

METHODS/DESIGN

A single-centre, prospective, double-blinded, randomized controlled trial will be conducted at Hebei General Hospital. Ninety-six elderly patients who undergo total hip or knee replacement will be studied in this trial and randomly divided into two groups. Patients in the experimental group will receive a loading dose of 0.5 μg/kg dexmedetomidine for 10 min and then a maintenance dose of 0.5 μg/kg/h dexmedetomidine until 30 min before the end of the operation, and patients in the control group will be infused with an equal volume of normal saline. The incidence of postoperative cognitive dysfunction will be the primary outcome. Changes in the balance of T helper 17 cell and regulatory T cell; the levels of matrix metalloproteinase 9, S-100β, IL-17A, and IL-10; perioperative complications; hospitalization duration; and intraoperative blood loss will be the secondary outcomes.

DISCUSSION

The consequences of this trial will show that dexmedetomidine can improve postoperative cognitive dysfunction in elderly orthopaedic patients, which may be related to the balance of T helper 17/regulatory T cells.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2200055802 . Registered on 20 January 2022.

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.

Inflammatory markers in postoperative cognitive dysfunction for patients undergoing total hip arthroplasty: a meta-analysis

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a poorly understood disorder, very common even after total hip arthroplasty (THA). It is widely considered that inflammation response play a role in the pathogenesis of POCD.

AIMS

The aim of the present study was to investigate whether inflammation cytokine concentrations could serve as biomarkers for POCD in patients undergoing THA.

METHODS

A systematic search of databases was conducted to retrieve publications measuring circulating inflammatory markers of patients with and without POCD after THA. Inflammatory markers identified in more than two studies were pooled. The standardized mean difference (SMD) and the 95% confidence interval (95% CI) were calculated for each outcome. Fail-safe N statistics was calculated to estimate possible publication bias.

RESULTS

The pooled incidence rate of POCD after THA by combining 11 cohort studies was 31%. A total of five inflammatory markers, CRP, S-100B, IL-1β, IL-6 and TNF-α, were assessed. Significantly higher pre-operative CRP (P = 0.012) and S-100B (P < 0.0001) as well as post-operative CPR (P = 0.005) and IL-6 (P < 0.0001) at 6 h were found in POCD compared with non-POCD patients undergoing THA. Fail-safe N statistics revealed that these results are robust.

DISCUSSION

The current evidence suggests that some of the inflammatory markers, including CRP, S-100B, and IL-6, were correlated with the occurrence of POCD after THA.

CONCLUSION

Monitor of inflammatory markers might help early diagnosis of POCD after THA and development of preventive strategies.