Dexmedetomidine versus sufentanil as adjuvants to bupivacaine for brachial plexus block during upper extremity surgery: a randomized clinical trial

Abstract Background: Brachial plexus block (BPB) has been accepted as a reliable alternative for general anesthesia in upper limb surgeries. Adding adjuvant drugs like dexmedetomidine and sufentanil has been shown to have clinical and pharmacologic advantages. In this randomized parallel clinical trial, we aim to compare the effects of these two adjuvants for bupivacaine in BPB. Methods: In this double-blinded study, by using computer-assisted block randomization, 40 patients ranged from 20 to 65 years old and scheduled for elective upper limb surgeries were assigned to two equal study groups (n = 20), receiving 1 mL of 5 μg.mL-1 sufentanil (group S) or 1 mL of 100 μg.mL-1 dexmedetomidine (group D) in adjunction to 30 mL of 0.5% bupivacaine for supraclavicular BPB under the guidance of ultrasonography. Characteristics of local anesthesia and postoperative analgesia were evaluated (n = 40). Results: The duration of blocks significantly improved in group S (sensory: estimated median difference (EMD) [95%CI] = 100.0 [70.0~130.0], p < 0.001; motor: EMD [95%CI] = 120.0 [100.0~130.0], p < 0.001). Group S also had significantly longer postoperative analgesia and lower opioid consumption within 24 hours after the surgery (EMD [95%CI] = 4.0 [3.0~7.0], p < 0.001; EMD [95%CI] = -5.0 [-5.0~-5.0], p < 0.001; respectively). None of the patients showed adverse effects concerning vital signs, nausea, or vomiting. Conclusion: Our study showed that during ultrasound-guided supraclavicular BPB, sufentanil is a fairly better choice than dexmedetomidine as an adjuvant for bupivacaine and can provide preferable sensory and motor blocks. No significant side effects were seen in either of the study groups.

Ultrasound Guided Fascia Iliaca Compartment Block Using Either Bupivacaine Or Bupivacaine With Dexmedetomidine For Postoperative Analgesia In Patients With Femur Fractures.

Background: Femur fractures are extremely painful due to the lowest pain threshold of the periosteum among the deep somatic structures. Perioperative Fascia Iliaca Compartment Block (FICB), when administered using a local anesthetic agent, bupivacaine, can reduce morbidity by providing satisfactory pain relief. Dexmedetomidine, an alpha-2 agonist, is known to prolong the local anesthetic effects without causing any significant side effects. We compared analgesic duration of ultrasound guided FICB with bupivacaine alone and bupivacaine with dexmedetomidine for postoperative analgesia. A prospective, randomized, double blinded study was conducted on 50 patientsMaterials And Method: aged 18 to 65 years undergoing femur fracture surgeries. Patients were divided into 2 groups of 25 each. Both groups received USG guided FICB. Group A received 28 ml 0.25% bupivacaine and 2 ml normal saline (NS). Group B received 28 ml 0.25% bupivacaine and 30 mcg dexmedetomidine in NS. Pain scores were assessed every 5 minutes until 15 minutes post FICB, during positioning for subarachnoid block and every 2 hours until 24 hours post-operatively. Total duration of analgesia, cumulative analgesia requested in 24 hours, Ramsay sedation and patient satisfaction scores were recorded. Results: The mean duration of analgesia in Group A was 419.4 ± 115.35 minutes (95%CI: 374.2 – 464.6) and in Group B was 656.6 ± 137.99 minutes (95%CI: 602.5 –710.7), p <0.001. Mean VAS score during positioning for SAB in Group A was 1.60 ± 0.50 and in Group B was 0.96 ± 0.68. USG guided FICB with dexmedetomidine is superior inConclusion: providing prolonged post-operative analgesia in comparison to bupivacaine alone

Single-bolus dexmedetomidine in prevention of emergence delirium in pediatric ophthalmic surgeries: A randomized controlled trial

Purpose: Emergency delirium (ED), a common postoperative neurologic complication, causes behavioral disturbances leading to self?traumas and also has long?term adverse effects in children. Our aim was to investigate the efficacy of a single?bolus dose of dexmedetomidine in reducing the incidence of ED. Additionally, pain relief, number of patients who needed rescue analgesia, hemodynamic parameters, and adverse events were assessed. Methods: One hundred and one patients were randomly allocated into two groups: 50 patients received 15 mL of dexmedetomidine 0.4 ?g/kg (group D) and 51 patients received volume?matched normal saline (group C). Hemodynamic parameters such as heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were monitored regularly throughout the procedure. ED was assessed with Pediatric Anesthesia Emergence Delirium Scale (PAEDS), and pain was measured using the modified Objective Pain Score (MOPS). Results: The incidences of ED and pain were higher in group C than group D (P < 0.0001 and P < 0.0001, respectively). Group D showed significant decrease in MOPS and PAEDS values at 5, 10, 15, and 20 min (P < 0.05), HR at 5 min (P < 0.0243), and SBP at 15 min (P < 0.0127). There was no significant difference in DBP between the two groups at any time point. The mean blood pressure (MBP) at 10 min was significantly less in group D than group C (P < 0.001). Conclusion: Dexmedetomidine 0.4 ?g/kg as a single bolus over 10 min immediately after intubation is effective for the prevention of ED and significantly reduces the need of rescue analgesia without compromising the hemodynamic parameters in children undergoing ophthalmic surgery.

The antioxidant effect of preischemic dexmedetomidine in a rat model: increased expression of Nrf2/HO-1 via the PKC pathway

Abstract Background The precise underlying mechanism of antioxidant effects of dexmedetomidine-induced neuroprotection against cerebral ischemia has not yet been fully elucidated. Activation of Nuclear factor erythroid 2-related factor (Nrf2) and Heme Oxygenase-1 (HO-1) represents a major antioxidant-defense mechanism. Therefore, we determined whether dexmedetomidine increases Nrf2/HO-1 expression after global transient cerebral ischemia and assessed the involvement of Protein Kinase C (PKC) in the dexmedetomidine-related antioxidant mechanism. Methods Thirty-eight rats were randomly assigned to five groups: sham (n = 6), ischemic (n = 8), chelerythrine (a PKC inhibitor; 5 mg.kg-1 IV administered 30 min before cerebral ischemia) (n = 8), dexmedetomidine (100 µg.kg-1 IP administered 30 min before cerebral ischemia (n = 8), and dexmedetomidine + chelerythrine (n = 8). Global transient cerebral ischemia (10 min) was applied in all groups, except the sham group; histopathologic changes and levels of nuclear Nrf2 and cytoplasmic HO-1 were examined 24 hours after ischemia insult. Results We found fewer necrotic and apoptotic cells in the dexmedetomidine group relative to the ischemic group (p< 0.01) and significantly higher Nrf2 and HO-1 levels in the dexmedetomidine group than in the ischemic group (p< 0.01). Additionally, chelerythrine co-administration with dexmedetomidine attenuated the dexmedetomidine-induced increases in Nrf2 and HO-1 levels (p< 0.05 and p< 0.01, respectively) and diminished its beneficial neuroprotective effects. Conclusion Preischemic dexmedetomidine administration elicited neuroprotection against global transient cerebral ischemia in rats by increasing Nrf2/HO-1 expression partly via PKC signaling, suggesting that this is the antioxidant mechanism underlying dexmedetomidine-mediated neuroprotection.

The impact of emergence delirium on hospital length of stay for children who underwent tonsillectomy/adenotonsillectomy: an observational retrospective study

Abstract Background Emergence Delirium (ED) is a combination of disturbance of perception and psychomotor agitation that is common in pediatric patients after general anesthesia, especially at preschool age. Since the effect of ED on the length of stay has been studied in adults but infrequently in children, the aim of this study was to investigate the relationship between ED and length of stay in this population. Methods A single center, retrospective, observational study was carried out in children who underwent tonsillectomy or adenotonsillectomy. The Pediatric Anesthesia Emergence Delirium (PAED) scale was used to assess ED. In addition to the time to hospital discharge (time frame 24 hours), drugs used, comorbidities, early postoperative complications, and pain were investigated if potentially associated with the complication. Results Four hundred sixteen children aged from 1.5 to 10 years (183 female, 233 male) were included. ED occurred in 25.5% of patients (n = 106). Patients were divided into the ED group and the No-ED group. The discharge time was similar in both groups. No significant differences were observed in the frequency of postoperative complications. The use of fentanyl or dexmedetomidine did not affect ED occurrence. The frequency of pain was greater in the ED group, both in the recovery room and in the ward (p= 0.01). Conclusions The occurrence of ED in children after tonsillectomy/adenotonsillectomy did not extend the length of stay.

A randomized comparative study of preoperative fentanyl and dexmedetomidine nebulization on the hemodynamic response to endotracheal intubation

Background: Intense sympathetic activity is linked to laryngoscopy and endotracheal intubation, which could lead to intraoperative problems. We undertook this study to compare the effects of preoperative nebulized Fentanyl and Dexmedetomidine on hemodynamic response to laryngoscopy and endotracheal intubation, taking advantage of their high bioavailability and better absorption through nasal mucosa. Aim and Objectives: The objectives of the study were (i) to compare the effect of preoperative nebulization on the hemodynamic response to laryngoscopy and intubation; and (ii) to assess intraoperative requirement of anesthetic agents. Materials and Methods: This prospective, randomized, and comparative study was conducted among 100 American Society of Anesthesiologists (ASA) I, II patients (of either gender) undergoing elective surgeries and requiring tracheal intubation, were randomized in two groups. Group A was given Fentanyl Nebulization (2 ?g/kg in 4 ml of 0.9% saline) and Group B was given Dexmedetomidine nebulization (1 ?g/kg in 4 ml of 0.9% saline) 10 min before anesthesia induction. Hemodynamic parameters were noted before and immediately after induction, 1 min, 5 min and 10 min after intubation. The main goal was to assess how Fentanyl and dexmedetomidine nebulization affect the laryngoscopy and intubation-induced stress response. The secondary outcome was to assess the intraoperative requirement of anesthetic agents, observe adverse effects of study drug and sedation score. Results: Dexmedetomidine nebulization was found to be more effective in blunting rise in heart rate post laryngoscopy compared to Fentanyl Nebulization (P < 0.0001) as well as in MAP after 10 min of intubation (P < 0.0001). Requirement of propofol was seen to be significantly reduced in Group B compared to Group A (P < 0.05). Sedation scores were significantly higher in Group B (P < 0.05). No evidence of side effects was observed in any group. Conclusion: Nebulisation of dexmedetomidine was found to be more effective in attenuation of stress response of laryngoscopy and intubation compared to nebulisation of fentanyl, with stable intraoperative hemodynamic and no significant side effects.

The effect of dexmedetomidine on expression of neuronal nitric oxide synthase in spinal dorsal cord in a rat model with chronic neuropathic pain / O efeito da dexmedetomidina na expressão do óxido nítrico sintase neuronal na medula espinhal dorsal em um modelo rato com dor neuropática crônica

Abstract Background Neuropathic pain typically refers to the pain caused by somatosensory system injury or diseases, which is usually characterized by ambulatory pain, allodynia, and hyperalgesia. Nitric oxide produced by neuronal nitric oxide synthase (nNOS) in the spinal dorsal cord might serve a predominant role in regulating the algesia of neuropathic pain. The high efficacy and safety, as well as the plausible ability in providing comfort, entitle dexmedetomidine (DEX) to an effective anesthetic adjuvant. The aim of this study was to investigate the effect of DEX on the expression of nNOS in spinal dorsal cord in a rat model with chronic neuropathic pain. Methods Male Sprague Dawley (SD) rats were randomly assigned into three groups: sham operation group (sham), (of the sciatic nerve) operation (CCI) group, and dexmedetomidine (DEX) group. Chronic neuropathic pain models in the CCI and DEX groups were established by sciatic nerve ligation. The thermal withdrawal latency (TWL) was measured on day 1 before operation and on day 1, 3, 7 and 14 after operation. Six animals were sacrificed after TWL measurement on day 7, and 14 days after operation, in each group, the L4-6 segment of the spinal cords was extracted for determination of nNOS expression by immunohistochemistry. Results Compared with the sham group, the TWL threshold was significantly decreased and the expression of nNOS was up-regulated after operation in the CCI and DEX groups. Compared with the CCI grou[, the TWL threshold was significantly increased and the expression of nNOS was significantly down-regulated on day 7 and 14 days after operation in the DEX group. Conclusion Down-regulated nNOS in the spinal dorsal cord is involved in the attenuation of neuropathic pain by DEX.

Resumo Antecedentes A dor neuropática refere-se tipicamente à dor causada por lesões ou doenças do sistema somatossensorial. De modo geral, é caracterizada por dor à ambulação, alodinia e hiperalgesia. O óxido nítrico produzido pela enzima óxido nítrico sintase neuronal (nNOS) na medula espinhal dorsal pode ter um papel predominante na regulação da dor neuropática. A alta eficácia e segurança, bem como a plausível capacidade de proporcionar conforto, faz com que a dexmedetomidina (DEX) seja um adjuvante anestésico eficaz. O objetivo deste estudo foi investigar o efeito da DEX na expressão de nNOS na medula espinhal dorsal em um modelo de ratos com dor neuropática crônica. Métodos Ratos Sprague Dawley (SD) machos foram distribuídos aleatoriamente em três grupos: grupo de cirurgia simulada (sham), grupo de cirurgia (do nervo ciático; CCI) e grupo dexmedetomidina (DEX). Os modelos de dor neuropática crônica nos grupos CCI e DEX foram estabelecidos por ligadura do nervo ciático. A latência de retirada térmica (TWL) foi medida no dia 1 antes da cirurgia e nos dias 1, 3, 7 e 14 após o procedimento. Seis animais de cada grupo foram eutanasiados após a medida de TWL nos dias 7 e 14 após a cirurgia e o segmento L4-6 da medula espinhal foi extraído para determinação da expressão de nNOS por imuno-histoquímica. Resultados Em comparação ao grupo sham, o limiar de TWL diminuiu significativamente e a expressão de nNOS foi regulada de maneira positiva após a cirurgia nos grupos CCI e DEX. Comparado ao grupo CCI, o limiar de TWL aumentou de forma significativa e a expressão de nNOS caiu significativamente diminuída nos dia 7 e 14 após a cirurgia no grupo DEX. Conclusão A regulação negativa de nNOS na medula espinhal dorsal está envolvida na atenuação da dor neuropática pela DEX.

Dexmedetomidina vía nasal en colecistectomía laparoscópica / Dexmedetomidine intranasally in laparoscopic cholecystectomy

Resumen: Introducción: la dexmedetomidina es un adyuvante en el manejo anestésico perioperatorio y si se administra por vía nasal las dosis requeridas tienen mínimos efectos secundarios. Material y métodos: ensayo clínico aleatorizado doble ciego en pacientes sometidos a colecistectomía laparoscópica con anestesia general, comparando la dexmedetomidina intranasal (1 μg/kg de peso ideal) contra placebo, se comparó el efecto analgésico postoperatorio por medio de la escala visual análoga del dolor (EVA) y el consumo de opioides transanestésico. El análisis estadístico se realizó con t de Student y exacta de Fisher. Resultados: se incluyeron 54 pacientes aleatorizados en dos grupos: dexmedetomidina y control. El 81.5% de los sujetos fueron mujeres, no se encontró diferencia entre los grupos en las variables demográficas. La media de la calificación EVA a los 60 minutos para el grupo dexmedetomidina fue (2.89 ± 1.9), estadísticamente inferior comparada contra el grupo control (5.78 ± 2.3) (p ˂ 0.0001). El consumo de opioides para dexmedetomidina fue (0.424 ± 0.074 μg/h) estadísticamente menor al control (0.697 ± 0.136 μg/h) (p ˂ 0.0001) con un tamaño del efecto de Cohen de 250%. Conclusiones: disminución significativa en EVA y en el consumo de opioides con el uso de dexmedetomidina intranasal en colecistectomía laparoscópica.

Abstract: Introduction: dexmedetomidine is and useful adjuvant agent in the perioperative anesthetic management associated to nasal administration with minimum adverse effects. Material and methods: a randomized, controlled, double blind, clinical trial was carried out in elective patients undergoing laparoscopic cholecystectomy with general anesthesia. Aim of this study was to compare the postoperative analgesic effect through visual analogue scale (VAS) and the perioperative opioid consumption. Dexmedetomidine was administrated intranasally (1 μg/kg dose) versus placebo. Statistical analysis was realized through student t and Fisher Test. Results: 54 patients were randomized in two groups: dexmedetomidine vs control. Not significant differences were found between both groups in demographic variables but 81.5% were women. Mean of VAS score at 60 minutes was significantly inferior (2.89 ± 1.9) versus control group (5.78 ± 2.3) (p ˂ 0.0001). Mean of opioids consumption in dexmedetomidine group (0.424 ± 0.074 μg/h) was significant minor of control group (0.697 ± 0.136 μg/h) (p ˂ 0.0001). Size effect through Cohen test was 250%. Conclusion: statistically decrease in VAS and in opioid consumption was observed using dexmedetomidine nasally in laparoscopic cholecystectomy.

Efficacy of dexmedetomidine as adjuvant to ropivacaine in paravertebral block for post-operative analgesia in breast cancer surgery

Background: Paravertebral block can be given for pain management after modified radical mastectomy (MRM). Although many additives to ropivacaine in PVB have been tried for post-operative analgesia, none has been found ideal. Aims and Objectives: We have compared the duration of analgesia in PVB using adjuvant like dexmedetomidine with ropivacaine after MRM. Materials and Methods: Sixty female patients posted for MRM and axillary dissection were split into two groups. Group R administered ultrasound-guided PVB with 20 ml ropivacaine 0.5% and Group RD administered 20 ml of 0.5% ropivacaine with dexmedetomidine 1 mcg/kg. After confirming PVB, surgery was done under general anesthesia in all patients. Time for 1st analgesia requirement was the main objective of our trial. Other objectives were to record visual analog scale scores and total analgesic need. Results: Post-operative analgesia duration was increased in the group RD (7.11 ± 1.42 h) in contrary to Group R (3.68 ± 1.85 h). Total paracetamol consumption post-operative 24 h was decreased in Group RD (1.63 ±0.89 g) in contrary to Group R (2.74 ± 0.76 g). Conclusion: Dexmedetomidine in PVB provides prolonged pain relief after MRM.

Effect of dexmedetomidine on tourniquet-induced skeletal muscle injury

SUMMARY OBJECTIVE: The aim of this study was to investigate whether dexmedetomidine could reduce tourniquet-induced skeletal muscle injury. METHODS: C57BL6 male mice were randomly assigned to sham, ischemia/reperfusion, and dexmedetomidine groups. Mice in the ischemia/reperfusion and dexmedetomidine groups received normal saline solution and dexmedetomidine intraperitoneally, respectively. The sham group underwent the same procedure as the ischemia/reperfusion group, with the exception of tourniquet application. Subsequently, the ultrastructure of the gastrocnemius muscle was observed, and its contractile force was examined. In addition, Toll-like receptor 4 and nuclear factor-κB expression within muscles was detected by Western blot. RESULTS: Dexmedetomidine alleviated myocyte damage and increased the contractility of skeletal muscles. Moreover, dexmedetomidine significantly inhibited the expression of Toll-like receptor 4/nuclear factor-κB in the gastrocnemius muscle. CONCLUSION: Taken together, these results demonstrate that dexmedetomidine administration attenuated tourniquet-induced structural and functional impairment of the skeletal muscle, partly through inactivation of the Toll-like receptor 4/nuclear factor-κB pathway.

Comparison of intranasal midazolam-fentanyl with dexmedetomidine–fentanyl as pre-medication in the paediatric age group

Background & objectives: Intranasal midazolam-fentanyl is commonly used as pre-medication in paediatric patients, but there is a risk of respiratory depression with this combination. Dexmedetomidine is a drug that preserves respiratory function. The objective of this study was to compare the efficacy of intranasal midazolam-fentanyl and dexmedetomidine-fentanyl in paediatric patients undergoing elective surgeries. Methods: Hundred children in the age group of 3-8 yr of American Society of Anaesthesiologists physical status grade 1 were randomized into two groups- group A received intranasal midazolam (0.2 mg/kg)-fentanyl (2 ?g/kg) and group B received intranasal dexmedetomidine (1 ?g/kg)-fentanyl (2 ?g/kg) 20 min before induction of general anaesthesia. Heart rate and SpO2 were monitored. Sedation score, parental separation and response to intravenous cannulation were seen after 20 min. Children were monitored for 2 h for post-operative analgesia by Oucher’s Facial Pain Scale. Results: Sedation scores were satisfactory in both groups, although children in group A were more sedated than in group B. Parental separation and response to intravenous cannulation were comparable in both the groups. The two groups were also haemodynamically comparable intraoperatively. Post-operative heart rate was also comparable at all-time intervals in both the groups except for heart rate at 100 and 120 min which were more in group A. Group A experienced more post-operative pain as assessed by Oucher’s Facial Pain Scale as compared to group B. Children receiving intranasal dexmedetomidine- fentanyl had better post-operative analgesia as compared to those who received intranasal midazolam-fentanyl. Interpretation & conclusions: Both intranasal midazolam with fentanyl and intranasal dexmedetomidine with fentanyl provided satisfactory sedation. Both groups were comparable in separation reaction and response to intravenous cannulation with better post-operative analgesia in children receiving intranasal dexmedetomidine-fentanyl.

O Pré-Condicionamento com Dexmedetomidina Atenua a Lesão de Isquemia/Reperfusão Miocárdica em Ratos, Suprimindo a Mitofagia Via Ativação do Receptor Α2-Adrenérgico / Dexmedetomidine Preconditioning Attenuates Myocardial Ischemia/Reperfusion Injury in Rats by Suppressing Mitophagy Via Activating Α2-Adrenergic Receptor

Resumo Fundamento A dexmedetomidina (DEX), um agonista específico do receptor α2-adrenérgico, é protetora contra lesão de isquemia/reperfusão miocárdica (I/R). No entanto, a associação entre a cardioproteção induzida pelo pré-condicionamento DEX e a supressão da mitofagia permanece pouco clara. Objetivo Portanto, nosso objetivo foi investigar se o pré-condicionamento com DEX alivia a I/R, suprimindo a mitofagia via ativação do receptor α2-adrenérgico. Método Sessenta corações de ratos isolados foram tratados com ou sem DEX antes de induzir isquemia e reperfusão; um antagonista do receptor α2-adrenérgico, a ioimbina (YOH), também foi administrado antes da isquemia, isoladamente ou com DEX. A frequência cardíaca (FC), pressão diastólica do ventrículo esquerdo (PDVE), pressão diastólica final do ventrículo esquerdo (PDFVE), taxa máxima e mínima de desenvolvimento da pressão ventricular esquerda (±dp/dtmax) e tamanho do infarto do miocárdio foram medidos. A ultraestrutura mitocondrial e as autofagossomas foram avaliadas por microscopia eletrônica de transmissão. O potencial de membrana mitocondrial e os níveis de espécies reativas de oxigênio (ROS) foram medidos usando os ensaios JC-1 e diacetato de diclorodi hidrofluoresceína, respectivamente. Os níveis de expressão das proteínas associadas à mitofagia Beclin1, relação LC3II/I, p62, PINK1 e Parkin foram detectados por western blotting. Resultados Em comparação com o grupo controle, no grupo isquemia/reperfusão, a FC, PDVE e ±dp/dtmax foram notavelmente diminuídas (p<0,05), enquanto os tamanhos da PDFVE e do infarto aumentaram significativamente (p<0,05). O pré-condicionamento com DEX melhorou significativamente a disfunção cardíaca, reduziu o tamanho do infarto do miocárdio, manteve a integridade estrutural mitocondrial, aumentou o potencial de membrana mitocondrial, inibiu a formação de autofagossomas e diminuiu a produção de ROS e a relação Beclin1, relação LC3II/I, expressão PINK1, Parkin e p62(p<0,05). Quando DEX e YOH foram combinados, o YOH cancelou o efeito da DEX, enquanto o uso de YOH sozinha não teve efeito. Conclusão Portanto, o pré-condicionamento DEX foi cardioprotetor contra I/R em ratos, suprimindo a mitofagia por meio da ativação do receptor α2-adrenérgico.

Abstract Background Dexmedetomidine (DEX), a specific α2-adrenergic receptor agonist, is protective against myocardial ischemia/reperfusion injury (MIRI). However, the association between DEX preconditioning-induced cardioprotection and mitophagy suppression remains unclear. Objective Hence, we aimed to investigate whether DEX preconditioning alleviates MIRI by suppressing mitophagy via α2-adrenergic receptor activation. Method Sixty isolated rat hearts were treated with or without DEX before inducing ischemia and reperfusion; an α2-adrenergic receptor antagonist, yohimbine (YOH), was also administered before ischemia, alone or with DEX. The heart rate (HR), left ventricular diastolic pressure (LVDP), left ventricular end-diastolic pressure (LVEDP), maximal and minimal rate of left ventricular pressure development (±dp/dtmax), and myocardial infarction size were measured. The mitochondrial ultrastructure and autophagosomes were assessed using transmission electron microscopy. Mitochondrial membrane potential and reactive oxygen species (ROS) levels were measured using JC-1 and dichloride hydrofluorescein diacetate assays, respectively. The expression levels of the mitophagy-associated proteins Beclin1, LC3II/I ratio, p62, PINK1, and Parkin were detected by western blotting. Results Compared with the control group, in the ischemia/reperfusion group, the HR, LVDP, and ±dp/dtmax were remarkably decreased (p< 0.05), whereas LVEDP and infarct sizes were significantly increased (p< 0.05). DEX preconditioning significantly improved cardiac dysfunction reduced myocardial infarction size, maintained mitochondrial structural integrity, increased mitochondrial membrane potential, inhibited autophagosomes formation, and decreased ROS production and Beclin1, LC3II/I ratio, PINK1, Parkin, and p62 expression(p< 0.05). When DEX and YOH were combined, YOH canceled the effect of DEX, whereas the use of YOH alone had no effect. Conclusion Therefore, DEX preconditioning was cardioprotective against MIRI in rats by suppressing mitophagy via α2-adrenergic receptor activation.

Effects of dexmedetomidine in non-operating room anesthesia in adults: a systematic review with meta-analysis

Abstract Background: Dexmedetomidine (DEX) is an α2-adrenergic receptor agonist used for its sedative, analgesic, and anxiolytic effects. Non-Operating Room Anesthesia (NORA) is a modality of anesthesia that can be done under general anesthesia or procedural sedation or/and analgesia. In this particular setting, a level-2 sedation, such as the one provided by DEX, is beneficial. We aimed to study the effects and safety of DEX in the different NORA settings in the adult population. Methods: A systematic review with meta-analysis of randomized controlled trials was conducted. Interventions using DEX only or DEX associated with other sedative agents, in adults (18 years old or more), were included. Procedures outside the NORA setting and/or without a control group without DEX were excluded. MEDLINE, ClinicalTrials.gov, Scopus, LILACS, and SciELO were searched. The primary outcome was time until full recovery. Secondary outcomes included hemodynamic and respiratory complications and other adverse events, among others. Results: A total of 97 studies were included with a total of 6,706 participants. The meta-analysis demonstrated that DEX had a higher time until full recovery (95% CI = [0.34, 3.13] minutes, a higher incidence of hypotension (OR = 1.95 [1.25, 3.05], p = 0.003, I2 = 39%) and bradycardia (OR = 3.60 [2.29, 5.67], p < 0.00001, I2 = 0%), and a lower incidence of desaturation (OR = 0.40 [0.25, 0.66], p = 0.0003, I2 = 60%). Conclusion: DEX in NORA procedures in adults was associated with a lower incidence of amnesia and respiratory effects but had a long time to recovery and more hemodynamic complications..

Dexmedetomidine versus clonidine as an adjuvant to local anaesthetic in brachial plexus blocks: a metaanalysis of randomised controlled trials

Abstract Objective: This meta-analysis aimed to compare the efficacy and safety of dexmedetomidine and Clonidine as an adjuvant to local anesthetics in BPBs. Methods: Two investigators independently searched databases to identify all RCTs comparing the efficacy and/or safety of dexmedetomidine and Clonidine as an adjuvant to local anesthetics in BPBs. All outcomes were pooled using the inverse variance method with a random-effect model. An I2 test was used to assess heterogeneity. The source of heterogeneity was explored through meta-regression. The quality of the evidence was assessed using the GRADE approach. Results: Out of 123 full texts assessed, 24 studies (1448 patients) were included in the analysis. As compared to Clonidine, dexmedetomidine groups showed significantly longer sensory block duration (MD = 173.31; 95% CI 138.02-208.59; I2 = 99%; GRADE approach evidence: high); motor block duration (MD = 158.35; 95% CI 131.55-185.16; I2 = 98%; GRADE approach evidence: high), duration of analgesia (MD = 203.92; 95% CI 169.25-238.58; I2 = 99%; GRADE approach evidence-high), and provided higher grade quality of block (RR = 1.97; 95% CI 1.60-2.41 ; I2 = 0%; GRADE approach evidence: moderate). The block positioning technique (regression coefficient: 51.45, p = 0.005) was observed as a significant predictor of the heterogeneity in the case of sensory block duration. No significant difference was observed for the risk of hypotension (RR = 2.59; 95% CI 0.63-10.66; I2 = %). Conclusion: Moderate to high-quality evidence suggests dexmedetomidine is a more efficacious adjuvant to local anesthetic in BPBs than Clonidine.

DEX, Delirium and Dilemma

ABSTRACT Dexmedetomidine has been subjected to an extensive evaluation for its' role in the prevention of postoperative delirium following cardiac surgery. In striking contrast to the preexisting meta-analysis supporting postoperative delirium-reduction with dexmedetomidine, few recently concluded multicentric large scale randomized controlled trials suggest otherwise. This article aims to present a nuanced perspective of the evolving controversy by attempting to decode the apparent incongruences in the literature accumulating off-late, which is particularly pertinent amidst an ever-escalating heterogeneity in the current research ecosystem.

Effects of dexmedetomidine on vital signs during postoperative anesthesia recovery period in gynecological patients undergoing general anesthesia surgery and analysis on risk factors for complications / 中国基层医药

Objective:To investigate the effects of dexmedetomidine on vital signs during recovery from general anesthesia in gynecological patients undergoing general anesthesia surgery and analysis of risk factors for complications.Methods:A total of 80 gynecological patients undergoing general anesthesia surgery who received treatment in Lishui People's Hospital from March 2021 to March 2022 were included in this study. They were randomly divided into an observation group and a control group ( n = 40/group). All patients were subjected to general anesthesia. The observation group was infused with 0.5 μg/kg dexmedetomidine intravenously 15 minutes before induction of anesthesia and then infused with dexmedetomidine at a rate of 0.2 μg/kg per hour until 20-30 minutes before the end of the operation. The control group was identically given 0.9% normal saline. The recovery quality, vital signs before surgery and during recovery from general anesthesia (systolic blood pressure, diastolic blood pressure, heart rate, body temperature), and complications during recovery from general anesthesia were compared between the two groups. These patients were divided into a complication group and a non-complication group according to whether there were complications during recovery from general anesthesia. Univariate and multivariate Logistic regression analyses were performed to analyze the high-risk factors for complications occurring during recovery from general anesthesia in gynecological patients undergoing general anesthesia surgery. Results:The time to awaken, time to recover spontaneous respiration, and time to extubation in the observation group were significantly shorter than those in the control group ( t = 3.74, 2.97, 2.56, all P < 0.05). Systolic blood pressure, diastolic blood pressure, and heart rate measured during recovery from general anesthesia were significantly lower in the observation group compared with the control group ( t = 5.71, 4.53, 4.53, all P < 0.001). Body temperature ( t = 4.40, P < 0.001) and the incidence of complications ( χ2 = 5.69, P < 0.05) were significantly lower in the observation group compared with the control group. These patients were divided into complication ( n = 22) and non-complication ( n = 58) groups according to whether they had complications during recovery from general anesthesia. Univariate and multivariate logistic regression analyses showed that American Association of Anesthesiologists grade II, presence of underlying diseases, abnormal leukocyte count, and no use of dexmedetomidine were the risk factors for postoperative complications in gynecological patients undergoing general anesthesia surgery ( OR = 2.38, 2.86, 2.17, 3.60, all P < 0.05). Conclusion:Dexmedetomidine can improve awakening quality and vital signs and reduce complications during recovery from general anesthesia. American Association of Anesthesiologists grade, underlying disease, abnormal white blood cell count, and no use of dexmedetomidine are the risk factors for complications occurring during recovery from general anesthesia in gynecological patients undergoing general anesthesia surgery.

Effect of dexmedetomidine on cough reactions during recovery from general anesthesia in thyroid tumor surgery / 中华地方病学杂志

Objective:To explore the effect of dexmedetomidine on cough reactions and related indexes during recovery from general anesthesia in thyroid tumor surgery.Methods:A total of 90 patients with thyroid tumor who underwent general anesthesia for thyroid tumor surgery from July 2019 to July 2021 in the First People's Hospital of Shangqiu City, Henan Province were selected and divided into the observation group (45 cases) and the control group (45 cases) according to the random number table method. The observation group was given dexmedetomidine 0.5 μg/kg intravenously at the beginning of the surgery, and the intravenous drip time should not be less than 10 min; the control group was given the same dose of normal saline intravenously. The recovery time and extubation time of the two groups were compared, and the incidence of cough reactions during the recovery from general anesthesia was compared. Changes of visual analogue scale (VAS) of pain at 6 h, 24 h and 48 h after surgery, and the changes of stress response indexes [cortisol (Cor), epinephrine (E) and norepinephrine (NE)] and pain factors [prostaglandin E2 (PGE2), neuropeptide Y (NPY) and β-endorphin (β-EP)] before and 48 h after surgery were compared.Results:The recovery time and extubation time in the observation group [(15.62 ± 3.64), (18.27 ± 4.25) min] were faster than those in the control group [(23.12 ± 4.53), (25.65 ± 3.89) min, P < 0.001]. The incidence of cough reactions during recovery from general anesthesia in the observation group [8.89% (4/45)] was lower than that in the control group [28.89% (13/45), P = 0.015]. The VAS score in the observation group was lower than that in the control group at 6 h, 24 h and 48 h after surgery ( P < 0.001). The levels of serum Cor, E and NE at 48 h after surgery in both groups were higher than those before surgery ( P < 0.001); and the serum Cor, E, and NE levels in the observation group were lower than those in the control group at 48 h after surgery ( P < 0.001). The serum PGE2 and NPY levels of the two groups at 48 h after surgery were higher than those before surgery, while β-EP level was lower than that before surgery ( P < 0.001); the serum PGE2 and NPY levels in the observation group were lower than those in the control group at 48 h after surgery, while β-EP level was higher than that in the control group ( P < 0.001). Conclusion:Dexmedetomidine can reduce the cough reactions during recovery from general anesthesia in thyroid tumor surgery, significantly reduce pain, and has little effect on stress response and pain factors.

Observation on the recovery effect of continuous infusion of dexmedetomidine combined with oxycodone in anesthesia intensive care unit for elderly patients undergoing thoracoscopic radical resection of lung cancer / 中国医师进修杂志

Objective:To compare the recovery effect of continuous infusion of dexmedetomidine combined with oxycodone or sufentanil in the anesthesia intensive care unit (AICU) in elderly patients after thoracoscopic radical surgery for lung cancer.Methods:Using the method of prospective study, 80 elderly lung cancer patients underwent selective thoracoscopic radical surgery under general anesthesia in Nanjing First Hospital from February 2021 to May 2022 were selected. The patients were divided into dexmedetomidine combined with sufentanil group (S group) and dexmedetomidine combined with oxycodone group (Q group) by random digits table method with 40 cases each group. On the basis of routine monitoring and treatment after operation, the patients in Q group were continuously injected with oxycodone 0.03 mg/(kg·h) and dexmedetomidine 0.4 μg/(kg·h) through analgesia pump, the patients in S group were continuously injected with sufentanil 0.03 mg/(kg·h) and dexmedetomidine 0.4 μg/(kg·h) through analgesia pump. The wake-up time, extubation time, awakening quality (Aldrete score and bucking score) and comfort level (Bruggrmann comfort scale score, BCS score) after entering the AICU were record; the sedation score (Ramsay score) and pain relief score (numerical rating scale score, NRS score) and hemodynamic changes (mean arterial pressure and heart rate) 3, 5, 7, 10 and 14 h after entering the AICU were record; the level of serum inflammatory factors, including tumor necrosis factor (TNF-α), interleukin-6 (IL-6) and C-reactive protein (CRP) immediately, 5 h and 14 h after entering the AICU; press times of analgesia pump, adverse events, bleeding volume of drainage tube during AICU and overall satisfaction score when leaving the AICU were record.Results:The bucking score in Q group was significantly lower than that in S group: (1.02 ± 0.77) scores vs. (1.88 ± 0.34) scores, the Aldrete score and BCS score were significantly higher than those in S group: (8.93 ± 0.25) scores vs. (5.97 ± 0.32) scores and (3.03 ± 0.32) scores vs. (0.93 ± 0.52) scores, and there were statistical differences ( P<0.01); there were no statistical difference in wake-up time and extubation time between two groups ( P>0.05). There were no statistical difference Ramassy score, NRS score 3 and 5 h after entering the AICU, mean arterial pressure and heart rate between two groups ( P>0.05); the Ramassy score 7, 10 and 14 h after entering the AICU in Q group was significantly lower than that in S group, the NRS score, mean arterial pressure and heart rate were significantly lower than those in S group, and there were statistical differences ( P<0.01). There were no statistical differences in TNF-α, IL-6 and CRP immediately after entering the AICU between two groups ( P>0.05); the TNF-α, IL-6 and CRP 5 and 14 h after entering the AICU in Q group were significantly lower than those in S group, and there were statistical difference ( P<0.01). The press times of analgesia pump, bleeding volume of drainage tube and the incidences of nausea vomiting, respiratory depression, lethargy, restlessness, fever and lung infection in Q group were significantly lower than those in S group: (4.63 ± 1.10) times vs. (18.80 ± 1.54) times, (129.67 ± 4.14) ml vs. (164.00 ± 8.14) ml, 10.0% (4/40) vs. 52.5% (21/40), 2.5% (1/40) vs. 25.0% (10/40), 7.5% (3/40) vs. 47.5% (19/40), 0 vs. 20.0% (8/40), 2.5% (1/40) vs. 22.5% (9/40) and 2.5% (1/40) vs. 20.0% (8/40), and there were statistical differences ( P<0.01 or <0.05); there was no severe hypotension, severe bradycardia and delirium in both groups. The overall satisfaction score in Q group was significantly higher than that in S group: (3.53 ± 0.63) scores vs. (2.70 ± 0.65) scores, and there was statistical difference ( P<0.01). Conclusions:Continuous micro-pump infusion of dexmedetomidine combined with oxycodone in AICU elderly patients with lung cancer after thoracoscopic radical surgery can significantly improve the quality of recovery and comfort during extubation, without affecting the extubation time, and can effectively reduce the degree of pain, stress and inflammatory reaction in the early recovery period, and reduce the incidence of adverse events after surgery.

Effects of Epidural Labor Analgesia plus Dexmedetomidine on Postpartum Depression in Parturients： A Prospective Study / 中山大学学报(医学科学版)

ObjectiveTo investigate the effects of epidural analgesia plus dexmedetomidine infusion on postpartum depression in parturients with natural childbirth. MethodsWe selected 70 parturients aged between 22 and 36， with singleton， term， cephalic presentation， natural delivery and ASA class I or Ⅱ. The cases undergoing epidural analgesia with ropivacaine and sufentanil were randomly divided into two groups by using a random number table （n=35 for each group）. The control group （Group C） used intravenous infusion of normal saline， while the experimental group （Group D） used equivalent volumes of intravenous infusion of dexmedetomidine. Participants were followed up at 1， 6， 12 weeks after childbirth to assess the severity of postpartum depression. Blood samples were collected at 12 h and 48 h after childbirth to measure the serum prolactin levels. The hemodynamic （HR and MAP） changes， VAS scores， and Ramsay scores were recorded at five time points： before analgesia （T1）， 10 min after analgesia （T2）， 30 min after analgesia （T3）， 12 h （T4） and 24 h （T5） after delivery. The number of analgesia pump presses and adverse events were also documented. ResultsCompared with Group C， Group D showed significantly lower EPDS scores at 1 week after childbirth， significantly higher prolactin concentrations at 12 h and 48 h after childbirth， significantly lower VAS scores at T2， T3 and T4， significantly higher Ramsay score at T3 and significantly reduced number of analgesia pump presses （P < 0.05）. ConclusionEpidural analgesia plus intravenous infusion of dexmedetomidine can alleviate early postpartum depression in women undergoing natural delivery， promote early prolactin secretion and provide a safe and effective adjunctive analgesic and sedative effect.