Dexmedetomidine Combined with General Anesthesia Provides Similar Intraoperative Stress Response Reduction When Compared with a Combined General and Epidural Anesthetic Technique

Retrobulbar dexmedetomidine in pediatric vitreoretinal surgery eliminates the need for intraoperative fentanyl and postoperative analgesia: A randomized controlled study

Purpose

This study evaluated the efficacy of retrobulbar ropivacaine plus dexmedetomidine compared with systemic fentanyl in pediatric vitreoretinal (VR) surgery.

Methods

This prospective double-blind, randomized controlled study was performed in 60 children undergoing VR surgery, age from 2 to 7 years. After general anesthesia, the following procedure was administrated: (1) retrobulbar block with 0.5% ropivacaine plus dexmedetomidine 1 μg/kg (group RD, n = 20), (2) retrobulbar block with 0.5% ropivacaine (group RB, n = 20), and (3) control group with general anesthesia only (group F, n = 20). Hemodynamics, postoperative pain scores, anesthetics consumption (remifentanil, propofol, fentanyl), and emergence agitation were recorded.

Results

Respiratory depression was observed in 7 of the 20 patients in group F after the laryngeal mask airway was removed in the operating room, compared with none in groups RD and RB. All patients in group F required intraoperative rescue fentanyl (average intraoperative fentanyl consumption, 26.6 ± 12.6 μg per patient). Some rescue fentanyl was required in group RB (three patients required one dose of rescue fentanyl). Patients in group RD required none. Groups RD and RB reported lower pain scores than group F at 4 h postoperatively (RD group: P < 0.001; RB group: P =0.002); pain scores in group RD were lower than that in group F at 6 h postoperatively (P < 0.001).

Conclusion

Retrobulbar dexmedetomidine as an adjuvant to ropivacaine is a safe and effective alternative to systemic fentanyl. This regimen provides better pain management, hemodynamic stability, and stress response suppression in pediatric VR surgery.

Effects of peri-operative intravenous administration of dexmedetomidine on emergence agitation after general anesthesia in adults: a meta-analysis of randomized controlled trials

Objective

The aim of the current meta-analysis was to assess the effect of dexmedetomidine on emergence agitation (EA) and the recovery outcomes after general anesthesia in adults.

Methods

We searched the PubMed, the Cochrane Central Register of Controlled Trials, Embase, Web of Science and clinicaltrials.gov for relevant randomized controlled trials (RCTs) investigating the effects of dexmedetomidine on the EA in adults after general anesthesia compared with placebo. The primary outcome was the incidence of EA. Secondary outcomes included other recovery outcomes after general anesthesia.

Results

Twelve RCTs (842 participants) met the eligibility criteria. A conventional random-effects meta-analysis demonstrated that peri-operative intravenous dexmedetomidine could be effective for the prevention of EA [risk ratio (RR) 0.49, Trial Sequential Analysis (TSA)-adjusted 95% confidence interval (CI) 0.35–0.68, P<0.00001]. In addition, the TSA indicated that the meta-analysis for the incidence of EA reached the required information size (370). Lower number of patients receiving dexmedetomidine required analgesia (P=0.0009). Extubation time was longer (P=0.03) and hypotension (P=0.03) was more common with dexmedetomidine. Moreover, no difference was found in the other outcomes.

Conclusion

Dexmedetomidine was shown to effectively decrease the incidence of EA and to reduce postoperative analgesic requirements. Yet, other recovery outcomes including extubation time, length of PACU stay, postoperative residual sedation, hypotension, bradycardia as well as postoperative nausea and vomiting provided no data that could be used to form final conclusions.

Optimal dose of pretreated-dexmedetomidine in fentanyl-induced cough suppression: a prospective randomized controlled trial

BACKGROUND

To investigate the optimal dose of pretreated-dexmedetomidine in fentanyl-induced cough (FIC) suppression.

METHODS

Patients of 180 undergoing elective surgery with general anesthesia, aged 18-65 years, BMI 18.5-30 kg/m2, ASA I or II, were equally randomized into four groups (n = 45) to receive intravenous pretreatment of dexmedetomidine with 0 (group 1), 0.3 (group 2), 0.6 (group 3) and 0.9 (group 4) mcg/kg over 10 mins, respectively. After the pretreatment, all patients were given a 5-s intravenous injection of fentanyl 4 mcg/kg. The symptoms of irritating cough including the severity and onset time were recorded for 1 min after fentanyl injection. General anesthesia induction was completed with midazolam, propofol and cisatracurium, then endotracheal tube or laryngeal mask was inserted and connected to an anesthesia machine. MAP, HR and SpO2 at the beginning of pretreatment (T0), 3 min (T1), 6 min (T2), 9 min (T3) and 12 min (T4) after the beginning of pretreatment were recorded. Side effects of dexmedetomidine, such as bradycardia, hypertension, hypotension, and respiratory depression were also recorded during the course.

RESULTS

Totally 168 patients completed the study. The incidences of cough were 52.4, 42.9, 11.9, and 14.3% in groups 1, 2, 3, and 4, respectively, with no significant differences between groups 1 and 2 (P > 0.05) and between groups 3 and 4 (P > 0.05). The incidence and severity of cough in groups 3 and 4 were significantly lower than those in groups 1 and 2 (P < 0.05). Compared to T0, HR at T2 (P < 0.05), T3 (P < 0.01), and T4 (P < 0.01) decreased significantly and MAP at T4 decreased significantly (P < 0.05) in group 4. Bradycardia occurred in 1 case and respiratory depression occurred in 1 case in group 4. Compared to group 1, the onset time of cough in the other 3 groups were delayed significantly (P < 0.05).

CONCLUSION

Pretreated dexmedetomidine 0.6 mcg/kg blous intravenous infusion over 10 mins could reduce FIC effectively without side effects.

TRIAL REGISTRATION

This study was registered in ClinicalTrials.gov (NCT03126422), April 13, 2017.

Ultrasound-Guided Continuous Femoral Nerve Block with Dexmedetomidine Combined with Low Concentrations of Ropivacaine for Postoperative Analgesia in Elderly Knee Arthroplasty

OBJECTIVES

This study aims to investigate the clinical effect of dexmedetomidine (DEX) combined with low concentrations of ropivacaine in ultrasound-guided continuous fem-oral nerve block for postoperative analgesia in elderly patients with total knee arthroplasty (TKA).

MATERIALS AND METHODS

Patients were divided into three groups: group C, group D1, and group D2. For postoperative analgesia, patients in group C were given 0.15% ropivacaine, patients in group D1 were given 0.15% ropivacaine + 0.02 μg × kg-1 × h-1 DEX, and patients in group D2 were given 0.15% ropivacaine + 0.05 μg × kg-1 × h-1 DEX. The visual analogue scores in the resting state, active state (AVAS), and passive functional exercise state (PVAS), degree of joint bending, and Ramsay scores were recorded.

RESULTS

The Ramsay scores were significantly higher, AVAS scores were significantly lower, PVAS scores were significantly decreased, the degree of joint bending was significantly higher, and the time to the first postoperative ambulation was shorter in groups D1 and D2 than group C. Furthermore, the time to the first postoperative ambulation was shorter in group D2 than in group D1, patients in groups D1 and D2 were more satisfied than patients in group C, and patients in group D2 were more satisfied than patients in group D1.

CONCLUSION

The protocol of 0.05 μg × kg-1 × h-1 of DEX combined with 0.15% ro-pivacaine in ultrasound-guided continuous femoral nerve block for postoperative analgesia in elderly patients with TKA provides a better analgesic effect than without DEX performance.

X.-Y.Z. and E.-F.Z. have contributed equally to this research.

[Effects of propofol sedation on psychological stress in surgical patients under epidural]

OBJECTIVE

To explore the effects of propofol sedation on psychological stress in patients undergoing surgery under epidural anesthesia.

METHODS

Sixty patients scheduled to undergo elective ileostomy closure under epidural anesthesia were randomized into propofol sedation group and control group (n=30). The patients in the sedation group received a loading dose of propofol of 0.6 mg·kg- 1· h- 1 followed by a maintenance dose with continuous infusion of 3 mg·kg- 1· h- 1 given after the Observer's Assessment of Alertness/Sedation (OAA/S) score reached 2-3. An equivalent volume of normal saline was administered in patients in the control group. The patients' preoperative and intraoperative anxiety scores were assessed with the State Anxiety Inventory (SAI) on the day before and on the first day after the surgery, respectively. The mean blood pressure (MBP), heart rate (HR), SpO2, OAA/S, and the indicators of psychological stress of brain functional state of the patients (including the wavelet index [WLi], anxiety index [ANXi], comfortable index [CFi] and pain index [Pi]) were recorded at 5 min after entering the operating room (T0), at the time of lumbar puncture (T1) and change to supine position after the puncture (T2), at 20 s (T3), 40 s (T4), and 60 s (T5) after intravenous administration, and at 2 min (T6), 4 min (T5), 6 min (T8), 8 min (T9), 10 min (T10) and 40 min (T11) after skin incision. The patient's satisfaction with anesthesia was assessed with the Visual Analog Scale (VAS) score on the first day after the operation. Serum cortisol level was measured before anesthesia and at the end of operation to calculate the changes in cortisol level.

RESULTS

The two groups of patients were comparable for preoperative SAI scores (P>0.05); The patients in the sedation group appeared to have lower intraoprative SAI scores, but this difference was not statistically significant (P=0.05). MBP, HR, and SpO2 at the time points from T6 to T10 and OAA/S, WLi, ANXi, CFi, and Pi at the time points from T6 to T11 were significantly lower in the sedation group (all P < 0.05), and these parameters were not significantly different between the two groups at the other time points (all P>0.05). The patient satisfaction scores were significantly higher in the sedation group (Z=2.07, P < 0.05). Compared with the preoperative levels, serum cortisol level at the end of the operation was increased in the sedation group but lowered in the control group, and the variations of serum cortisol level differed significantly between the two groups (t=4.75, P < 0.01).

CONCLUSIONS

Intraoperative propofol sedation can alleviate the patients' anxiety, improve the comfort level, and lessen physiological stress during surgeries under epidural anesthesia.

Optimal concentration of the transversus abdominis plane block in enhanced recovery after surgery protocols for patients of advanced age undergoing laparoscopic rectal cancer surgery

Objective

The transversus abdominis plane (TAP) block ameliorates visual analogue scale scores and decreases morphine requirements, but its role remains unclear. Patients of advanced age are susceptible to local anesthetic intoxication. We aimed to identify an optimal concentration that can be used in enhanced recovery after surgery (ERAS) without compromising analgesic efficacy.

Methods

In total, 120 patients aged ≥65 years undergoing laparoscopic rectal cancer surgery received general anesthesia combined with a TAP block using 0.25% ropivacaine (Group A), 0.50% ropivacaine (Group B), or 0.75% ropivacaine (Group C) in a 40-mL volume. Group D only received general anesthesia. Epinephrine, plasma cortisol, interleukin-6, and tumor necrosis factor-α were measured at baseline, skin incision, celiac exploration, and tracheal extubation. The proportions of CD4⁺ and CD4⁺/CD8⁺ cells were measured at baseline and postoperative days 1 and 3.

Results

The TAP block relieved the stress response and accelerated intestinal functional recovery as shown by significant reductions in VAS scores and anesthetic requirements. However, there was no significant difference between Groups B and C.

Conclusion

The TAP block plays an important role in ERAS in older patients undergoing laparoscopic rectal cancer surgery, and 0.5% ropivacaine is an optimal concentration that can reduce toxicity without undermining analgesia.

Effect of dexmedetomidine on blood coagulation in patients undergoing radical gastrectomy under general anesthesia: A prospective, randomized controlled clinical trial

BACKGROUND

Dexmedetomidine can inhibit the perioperative stress response, which plays an important role in postoperative hypercoagulability. This study aimed to investigate whether dexmedetomidine could attenuate the activation of postoperative coagulation.

METHODS

Patients undergoing open radical gastrectomy under total intravenous anesthesia were randomly allocated to the control group (group Con) and the dexmedetomidine group (group Dex). Dexmedetomidine was intravenously infused at 0.5 μg/kg over 10 minutes before anesthesia induction and then infused at a rate of 0.5 μg/kg/h until peritoneal closure in group Dex, whereas saline was administered in group Con. Blood samples were collected for thrombelastograph (TEG) analysis [reaction time (R time), clot formation time (K time), and clot formation rate (α angle)] and laboratory coagulation testing before dexmedetomidine administration and at the end of surgery.

RESULTS

Coagulation was activated after radical gastrectomy, as indicated by TEG analysis and the increased concentrations of plasma fibrin (fibrinogen) degradation product (FDP) and thrombin-antithrombin complex (TAT). The R and K times were significantly prolonged and α angle was significantly decreased in group Dex compared with that in group Con at the end of surgery (P < .05). The concentrations of plasma TAT and FDP in group Dex were significantly lower than those in group Con at the end of surgery (P < .05 or .01).

CONCLUSION

Adjunctive dexmedetomidine with general anesthesia attenuates the activation of coagulation following radical gastrectomy.

Impact of dexmedetomidine infusion during general anaesthesia on incidence of postoperative delirium in elderly patients after major non-cardiac surgery: study protocol of a randomised, double-blinded and placebo-controlled trial

INTRODUCTION

Delirium is a common complication in the elderly after surgery and is associated with worse outcomes. Multiple risk factors are related with postoperative delirium, such as exposure to general anaesthetics, pain and postoperative inflammatory response. Preclinical and clinical studies have shown that dexmedetomidine attenuated neurotoxicity induced by general anaesthetics, improved postoperative analgesia and inhibited inflammatory response after surgery. Several studies found that intraoperative use of dexmedetomidine can prevent postoperative delirium, but data were inconsistent. This study was designed to investigate the impact of dexmedetomidine administered during general anaesthesia in preventing delirium in the elderly after major non-cardiac surgery.

METHODS AND ANALYSIS

This is a randomised, double-blinded and placebo-controlled trial. 620 elderly patients (age ≥60 years) who are scheduled to undertake elective major non-cardiac surgery (with an expected duration ≥2 hours) are randomly divided into two groups. For patients in the dexmedetomidine group, a loading dose dexmedetomidine (0.6 µg/kg) will be administered 10 min before anaesthesia induction, followed by a continuous infusion at a rate of 0.5 µg/kg/hour until 1 hour before the end of surgery. For patients in the control group, normal saline will be administered with an identical rate as in the dexmedetomidine group. The primary endpoint is the incidence of delirium during the first five postoperative days. The secondary endpoints include pain intensity, cumulative opioid consumption and subjective sleep quality during the first three postoperative days, as well as the incidence of non-delirium complications and all-cause mortality within 30 days after surgery.

ETHICS AND DISSEMINATION

The study protocol was approved by the Clinical Research Ethics Committee of Peking University First Hospital (2015-987) and registered at Chinese Clinical Trial Registry (http://www.chictr.org.cn) with identifier ChiCTR-IPR-15007654. The results of the study will be presented at academic conferences and submitted to peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ChiCRR-IPR-15007654; Pre-results.