Premedication with dexmedetomidine in pediatric patients: a systematic review and meta-analysis

Effectiveness of preoperative intranasal dexmedetomidine, compared with oral midazolam, for the prevention of emergence delirium in the pediatric patient undergoing general anesthesia: a systematic review

BACKGROUND

Emergence delirium is defined as a cognitive disturbance during emergence from general anesthesia resulting in hallucinations, delusions and confusion manifested by agitation, restlessness, involuntary physical movement and extreme flailing in bed. Postoperative emergence delirium develops in 12% to 18% of all children undergoing general anesthesia for surgery. This post-anesthetic phenomenon changes cognitive and psychomotor behavior, and puts pediatric patients and health care personnel at risk of injury. A newer drug, dexmedetomidine, is a selective alpha-2 agonist, which works in the brain and spinal cord that has sedative, analgesic and anxiolytic properties. Dexmedetomidine also has the ability to lower the overall anesthetic requirements by reducing sympathetic outflow in response to painful surgical stimulation. In current literature, there is not a systematic review that compares the effectiveness of preoperative intranasal dexmedetomidine administration against oral midazolam for the prevention of emergence delirium.

OBJECTIVES

The objective of this review was to identify the effectiveness of preoperative intranasal dexmedetomidine compared to oral midazolam for the prevention of emergence delirium in the pediatric patient undergoing general anesthesia.

INCLUSION CRITERIA TYPES OF PARTICIPANTS

This review considered studies that included pediatric patients aged three to seven years, with an American Society of Anesthesiologists (ASA) classification of I or II, and undergoing general anesthesia for elective/ambulatory surgery. This review excluded studies that included patients who had special needs including: developmental delay, chronic pain issues, and/or any preexisting mental or physical health disorders which categorized them above an ASA II.

TYPES OF INTERVENTION(S)/PHENOMENA OF INTEREST

This review considered studies that compared preoperative intranasal administration of dexmedetomidine with preoperative oral administration of midazolam for the prevention of emergence delirium.

TYPES OF STUDIES

This review considered both experimental and non-experimental study designs including randomized-controlled trials (RCTs), non-randomized control trials, quasi-experimental, before and after studies, prospective and retrospective cohort studies, case control studies, and analytical cross-sectional studies for inclusion.

OUTCOMES

This review considered studies that included the presence of postoperative emergence delirium. Only studies that used the Pediatric Anesthesia Emergence Delirium Scale to quantify the degree of emergence delirium were included in the review. Adverse events other than emergence delirium were not considered as part of the outcomes inclusion criteria but were to be included in the discussion if any articles were identified.

SEARCH STRATEGY

The search strategy aimed to discover both published as well as unpublished studies. A three-step search strategy was utilized in eight databases. Studies published in English or with an English translation after 1999 were considered for inclusion in this review.

METHODOLOGICAL QUALITY

Assessment of methodological quality was not conducted as no studies were identified which met the inclusion criteria.

DATA EXTRACTION AND SYNTHESIS

Data extraction and synthesis was not performed since no studies were included in this systematic review.

RESULTS

Following the three-step search strategy as previously described, 117 articles were identified: six in Clinical Trials, one in ProQuest, 14 in Ovid MEDLINE, 10 in CINAHL, 16 in the Cochrane Library, 13 in Scopus, 36 in Embase, and 21 in Web of Science. There were 43 duplicates which were identified and removed in Refworks by the primary reviewer. The primary and secondary reviewers independently retrieved 10 potentially relevant studies (from the initial 74) through title and abstract screening as described in the inclusion criteria. All of the retrieved studies were excluded, after assessment of full text, with reasons based on the inclusion criteria.

CONCLUSIONS

There is no scientific evidence identifying the effectiveness of preoperative intranasal dexmedetomidine, compared with oral midazolam, for the prevention of emergence delirium in the pediatric patient population.

Effects of dexmedetomidine versus midazolam for premedication in paediatric anaesthesia with sevoflurane: A meta-analysis

Background Dexmedetomidine (DEX), an α₂-adrenergic receptor agonist, produces ideal sedation and early postoperative recovery for premedication in paediatric surgery, reducing preoperative anxiety and facilitating smooth induction of anaesthesia. We performed a meta-analysis to compare the effects of DEX and midazolam (MDZ) in paediatric anaesthesia with sevoflurane. Methods PubMed, Ovid, Web of Science, and Public Health Management Corporation were searched through December 2016 for randomized controlled trials (RCTs) that compared DEX and MDZ in children undergoing sevoflurane anaesthesia. The risk ratio (RR) with 95% incidence interval (95%CI) was used for dichotomous variables. Results Twelve RCTs involving 422 patients in the DEX group and 448 patients in the MDZ group were included. Patients in the DEX group had a significantly lower incidence of unsatisfactory sedation (RR [95%CI] = 0.71 [0.57-0.89]), unsatisfactory parental separation (RR [95%CI] = 0.56 [0.35-0.87]), and rescue analgesia (RR [95%CI] = 0.52 [0.35-0.77]) than patients in the MDZ group. However, both groups had a similar incidence of unsatisfactory mask acceptance, emergence agitation, and postoperative nausea and vomiting. Conclusion Compared with MDZ, DEX is beneficial in paediatric anaesthesia with sevoflurane because of its lower incidence of unsatisfactory sedation, parental separation, and rescue analgesia.

Comparison of oral dexmedetomidine versus oral midazolam as premedication to prevent emergence agitation after sevoflurane anaesthesia in paediatric patients

Background and Aims:

Sevoflurane is the most often used inhalational agent in paediatric anaesthesia, but emergence agitation (EA) remains a major concern. Oral midazolam and parenteral dexmedetomidine are known to be effective in controlling EA. We attempted to elucidate whether oral dexmedetomidine is better than midazolam in controlling EA.

Methods:

Prospective double-blinded study involving ninety patients aged 1–10 years, undergoing elective surgeries of <2 h of expected duration under sevoflurane general anaesthesia, randomised to receive either midazolam (Group A) or dexmedetomidine (Group B) as oral premedication was carried out to record level of sedation before induction, haemodynamic parameters and recovery time. Incidence and severity of EA, post-operative pain and requirement of rescue analgesic were assessed at 0, 5, 15, 30 and 60 min postoperatively.

Results:

Data were analysed applying Student's t-test and Chi-square test using SPSS software. Mask acceptance was better in Group B (97.8% vs. 73.4%, P < 0.001). Mean arterial pressure was lower in Group B (P < 0.001) though clinically not significant. More rescue analgesic was required in Group A (5.6% vs. 0%). There was no significant difference in adverse effects. Although there was a higher incidence of EA in Group A (Aono's score 3 and 4; 40% vs. 4.4%), none of them required intervention (paediatric anaesthesia emergence delirium score >10; 0 vs. 0).

Conclusion:

Premedication with oral dexmedetomidine provides smooth induction and recovery, reduces the EA and provides better analgesia and sedation as compared to oral midazolam.

Efficacy of intranasal dexmedetomidine versus oral midazolam for paediatric premedication

Background and Aims:

Premedication is an integral component of paediatric anaesthesia which, when optimal, allows comfortable separation of the child from the parent for induction and conduct of anaesthesia. Midazolam has been accepted as a safe and effective oral premedicant. Dexmedetomidine is a selective alpha-2 agonist with sedative and analgesic effects, which is effective through the transmucosal route. We compared the efficacy and safety of standard premedication with oral midazolam versus intranasal dexmedetomidine as premedication in children undergoing elective lower abdominal surgery.

Methods:

This was a prospective randomised double-blinded trial comparing the effects of premedication with 0.5 mg/kg oral midazolam versus 1 μg/kg intranasal dexmedetomidine in children between 2 and 12 years undergoing abdominal surgery. Sedation scores at separation and induction were the primary outcome measures. Behaviour scores and haemodynamic changes were secondary outcomes. Student's t-test and Chi-square were used for analysis of the variables.

Results:

Sedation scores were superior in Group B (dexmedetomidine) than Group A (midazolam) at separation and induction (P < 0.001). The behaviour scores at separation, induction and wake up scores at extubation were similar between the two groups. The heart rate and blood pressure showed significant differences at 15, 30 and 45 min in Group B but did not require pharmacological intervention for correction.

Conclusion:

Intranasal dexmedetomidine at a dose of 1 μg/kg produced superior sedation scores at separation and induction but normal behavioural scores in comparison to oral midazolam in paediatric patients.

Effectiveness of preoperative intranasal dexmedetomidine compared with oral midazolam for the prevention of emergence delirium in pediatric patients undergoing general anesthesia: a systematic review protocol

This review aims to identify the effectiveness of preoperative intranasal dexmedetomidine compared with oral midazolam for the prevention of emergence delirium in pediatric patients undergoing general anesthesia.

The Influence of Dexmedetomidine on Ultrasound-induced Pulmonary Capillary Hemorrhage in Rats

The use of xylazine, a veterinary sedative, with ketamine for rat anesthesia has been shown to enhance the pulmonary capillary hemorrhage (PCH) effect of diagnostic ultrasound. This study was undertaken to assess whether the sedative/analgesic dexmedetomidine, commonly used in the intensive care unit, can also enhance ultrasound-induced PCH. Female Sprague Dawley rats were anesthetized with various combinations of ketamine plus xylazine or dexmedetomidine. The dosage of dexmedetomidine was reduced for some groups to doses relevant to human clinical usage. The right thorax of all rats was shaved and depilated for ultrasound transmission and the rats were scanned with diagnostic ultrasound using a 7.6-MHz linear array in a 38°C de-gassed water bath. There was no significant difference in PCH results for the recommended anesthetic dosages of ketamine plus xylazine and ketamine plus 500 μg/kg dexmedetomidine. The varied doses of dexmedetomidine enhanced the PCH, even for the lowest dose of 4 μg/kg, equivalent to a low human dose of 0.64 μg/kg. There was no significant difference in PCH for 500 μg/kg dexmedetomidine with or without ketamine. Further research is needed to identify and characterize other factors that may modify the patient risk from ultrasound-induced PCH.

Dexmedetomidine attenuates isoflurane-induced cognitive impairment through antioxidant, anti-inflammatory and anti-apoptosis in aging rat

As a kind of α2 adrenergic receptor agonists, dexmedetomidine generates sedation, anti-anxiety and anesthesia effects by hyperpolarizing noradrenergic nerve cells in locus coeruleus. This study was designed to investigate the neuroprotective of dexmedetomidine attenuates isoflurane-induced cognitive impairment, and the possible underlying mechanism in aging rat. Firstly, we used isoflurane-induced aging rat model to analyze the therapeutical effect of dexmedetomidine on cognitive impairment. Next, commercial ELISA kits were used to analyze tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), methane dicarboxylic aldehyde (MDA) and superoxide dismutase (SOD) and caspase-3 levels. In addition, Western blotting was used to detect the protein expression of P38 MAPK, PTEN and phosphorylation-Akt (p-Akt) expression. Our results showed that the neuroprotective of dexmedetomidine significantly attenuates isoflurane-induced cognitive impairment in aging rat. Moreover, dexmedetomidine significantly inhibited these TNF-α, IL-1β, MDA, SOD and caspase-3 activities in isoflurane-induced aging rat. Meanwhile, the neuroprotective effects of dexmedetomidine on isoflurane-induced cognitive impairment significantly suppressed Bcl-xL/Bad rate, P38 MAPK and PTEN protein expression and activated p-Akt protein expression in aging rat. Collectively, neuroprotective effect of dexmedetomidine attenuates isoflurane-induced cognitive impairment through antioxidant, anti-inflammatory and anti-apoptosis in aging rat.

Flurbiprofen Axetil Enhances Analgesic Effects of Sufentanil and Attenuates Postoperative Emergence Agitation and Systemic Proinflammation in Patients Undergoing Tangential Excision Surgery

Objective. Our present study tested whether flurbiprofen axetil could reduce perioperative sufentanil consumption and provide postoperative analgesia with decrease in emergency agitation and systemic proinflammatory cytokines release. Methods. Ninety patients undergoing tangential excision surgery were randomly assigned to three groups: (1) preoperative dose of 100 mg flurbiprofen axetil and a postoperative dose of 2 μg/kg sufentanil and 10 mL placebo by patient-controlled analgesia (PCA) pump, (2) preoperative dose of 100 mg flurbiprofen axetil and a postoperative dose of 2 μg/kg sufentanil and 100 mg flurbiprofen axetil by PCA pump, and (3) 10 mL placebo and a postoperative dose of 2 μg/kg sufentanil and 10 mL placebo by PCA pump. Results. Preoperative administration of flurbiprofen axetil decreased postoperative tramadol consumption and the visual analog scale at 4, 6, 12, and 24 h after surgery, which were further decreased by postoperative administration of flurbiprofen axetil. Furthermore, flurbiprofen axetil attenuated emergency agitation score and Ramsay score at 0, 5, and 10 min after extubation and reduced the TNF-α and interleukin- (IL-) 6 levels at 24 and 48 h after the operation. Conclusion. Flurbiprofen axetil enhances analgesic effects of sufentanil and attenuates emergence agitation and systemic proinflammation in patients undergoing tangential excision surgery.