Clonidine premedication versus placebo: effects on postoperative agitation and recovery time in children undergoing strabismus surgery

Electroencephalographic insights into the pathophysiological mechanisms of emergence delirium in children and corresponding clinical treatment strategies

Emergence delirium is a common postoperative complication in patients undergoing general anesthesia, especially in children. In severe cases, it can cause unnecessary self-harm, affect postoperative recovery, lead to parental dissatisfaction, and increase medical costs. With the widespread use of inhalation anesthetic drugs (such as sevoflurane and desflurane), the incidence of emergence delirium in children is gradually increasing; however, its pathogenesis in children is complex and unclear. Several studies have shown that age, pain, and anesthetic drugs are strongly associated with the occurrence of emergence delirium. Alterations in central neurophysiology are essential intermediate processes in the development of emergence delirium. Compared to adults, the pediatric nervous system is not fully developed; therefore, the pediatric electroencephalogram may vary slightly by age. Moreover, pain and anesthetic drugs can cause changes in the excitability of the central nervous system, resulting in electroencephalographic changes. In this paper, we review the pathogenesis of and prevention strategies for emergence delirium in children from the perspective of brain electrophysiology-especially for commonly used pharmacological treatments-to provide the basis for understanding the development of emergence delirium as well as its prevention and treatment, and to suggest future research direction.

Effects of preoperative nasal spray esketamine on separation anxiety and emergence agitation in pediatric strabismus surgery: A randomized clinical trial

OBJECTIVE

To investigate the effects of preoperative nasal spray esketamine on separation anxiety and postoperative emergence agitation in pediatric strabismus surgery.

METHOD

Ninety children aged 3 to 6 years who underwent elective strabismus surgery were randomly divided into 3 groups that received 0.5 mg/kg (group S1), 1 mg/kg of esketamine (group S2), and the same volume of normal saline (group C) by nasal spray 10 minutes before surgery. The observation indicators of this test include the Ramsay sedation score, separation anxiety score, mask induction score, and the incidences of postoperative emergence agitation. Patient's heart rate, blood oxygen, post anesthesia care unit stay time, and any adverse events were recorded.

RESULTS

The Ramsay sedation score was significantly lower in group C than those in groups S1 and S2 (P < .001). The separation anxiety scores and the mask induction scores were significantly higher in group C than those in groups S1 and S2 (P < .001). The incidences of emergence agitation in groups S1 and S2 were significantly lower than that in C group (P < .001). No obvious clinical complication was observed.

CONCLUSION

Preoperative nasal spray esketamine reduced the preoperative separation anxiety and decrease emergence agitation in pediatric strabismus surgery.

Safety and efficacy of clonidine on postoperative vomiting and pain in pediatric ophthalmic surgery: A systematic review and meta-analysis

BACKGROUND

Postoperative vomiting and pain are common, unpleasant phenomena in pediatric patients undergoing ophthalmic surgery. Clonidine has antiemetic and analgesic properties and thus may be used as premedication to reduce postoperative vomiting and pain.

AIM

To assess whether clonidine premedication may safely decrease postoperative vomiting and postoperative pain in pediatric patients who received an ophthalmic surgery.

METHODS

We systematically searched PubMed, EMBASE, Cochrane Library, and Scopus databases from their inception to September 2018. Randomized clinical trials comparing clonidine premedication with a placebo or an active comparator that investigated postoperative vomiting or postoperative pain in pediatric patients undergoing ophthalmic surgery were included. The primary outcome was postoperative vomiting. The secondary outcome was postoperative pain. We also evaluated the safety of clonidine premedication by tracking hemodynamic instability associated with its use.

RESULTS

Ten studies with 979 patients were eligible for inclusion. Clonidine achieved a significantly lower incidence of postoperative vomiting within 6 hours postoperatively, 6-24 hours postoperatively, and at the end of the study (risk difference: -0.15; 95% confidence interval: -0.32 to -0.05; risk difference: -0.15; 95% confidence interval: -0.29 to 0.01; and risk difference: -0.23; 95% confidence interval: -0.34 to -0.12, respectively) than placebo. For the subgroup of patients who received strabismus surgery, clonidine produced a lower incidence of postoperative vomiting than placebo (risk difference: -0.19; 95% confidence interval: -0.29 to -0.05). Compared to benzodiazepine, clonidine achieved a lower incidence of postoperative vomiting at the end of the study (risk difference: -0.19; 95% confidence interval: -0.31 to -0.07); the effect was only observed in patients receiving clonidine 4 μg/kg. Furthermore, children receiving clonidine had lower postoperative pain scores, lower analgesic requirements, and more of them were pain-free compared to those who received a placebo. No patient using clonidine had any major hemodynamic instability.

CONCLUSION

Compared to placebo or benzodiazepine, clonidine premedication was effective in reducing postoperative vomiting in pediatric patients undergoing ophthalmic surgery. Clonidine premedication also provided more reduction in postoperative pain when compared to placebo. The use of clonidine premedication was not associated with adverse hemodynamic events.

Effect of ancillary drugs on sevoflurane related emergence agitation in children undergoing ophthalmic surgery: a Bayesian network meta-analysis

BACKGROUND

The comparative efficacy of ancillary drugs on sevoflurane related emergence agitation (EA) in children undergoing ophthalmic surgery remains controversial.

METHODS

The databases were retrieved in an orderly manner from the dates of their establishment to October, 2018, including PubMed, The Cochrane Library and Web of Science, to collect randomized controlled trials (RCT) of different anesthetic drugs combined with sevoflurane for ophthalmic surgery. Then a network meta-analysis was conducted using R and Stata 12.0 softwares.

RESULTS

The meta-analysis showed that, in reducing sevoflurane related EA, dexmedetomidine, ketamine, propofol, fentanyl, midazolam, sufentanil, remifentanil and clonidine were superior to placebo (P < 0.05). The network meta-analysis showed that the effects of ancillary drugs combine with sevoflurane in reducing risk of EA in children undergoing ophthalmic surgery was superior to placebo: dexmedetomidine (OR = 0.17, 95% CrI 0.12-0.22), ketamine (OR = 0.30, 95% CrI 0.11-0.49), propofol (OR = 0.24, 95% CrI 0.09-0.63), fentanyl (OR = 0.16, 95% CrI 0.08-0.56), midazolam (OR = 0.20, 95% CrI 0.09-0.40), sufentanil (OR = 0.27, 95% CrI 0.14-0.41), remifentanil (OR = 0.18, 95% CrI 0.08-0.54) and clonidine (OR = 0.14, 95% CrI 0.07-0.41). The SUCRA of placebo, dexmedetomidine, ketamine, propofol, fentanyl, midazolam, sufentanil, remifentanil, clonidine were respectively 0.26, 77.93, 27.71, 42.8, 69.43, 52.89, 59.83, 57.62 and 61.53%.

CONCLUSIONS

The effects of dexmedetomidine combine with sevoflurane in reducing risk of emergence agitation in children undergoing ophthalmic surgery was superior to other drugs.

Perioperative considerations and anesthesia management in patients with obstructive sleep apnea undergoing ophthalmic surgery

Obstructive sleep apnea (OSA) is a disorder characterized by breathing cessation caused by obstruction of the upper airway during sleep. It is associated with multiorgan comorbidities such as obesity, hypertension, heart failure, arrhythmias, diabetes mellitus, and stroke. Patients with OSA have an increased prevalence of ophthalmic disorders such as cataract, glaucoma, central serous retinopathy (detachment of retina, macular hole), eyelid laxity, keratoconus, and nonarteritic anterior ischemic optic neuropathy; and some might require surgery. Given that OSA is associated with a high incidence of perioperative complications and more than 80% of surgical patients with OSA are unrecognized, all surgical patients should be screened for OSA (eg, STOP-Bang questionnaire) with comorbidities identified. Patients suspected or diagnosed with OSA scheduled for ophthalmic surgery should have their comorbid conditions optimized. This article includes a review of the literature and highlights best perioperative anesthesia practices in the management of ophthalmic surgical patients with OSA.

Efficacy of premedication with intranasal dexmedetomidine on inhalational induction and postoperative emergence agitation in pediatric undergoing cataract surgery with sevoflurane

STUDY OBJECTIVES

This study aimed to test the hypothesis that premedication with a single dose of intranasal dexmedetomidine (DEX) could not only reduce preoperative anxiety but also minimize the emergence agitation in children undergoing cataract surgery with sevoflurane anesthesia.

DESIGN

Single-blinded, randomized, placebo-controlled clinical comparison study.

SETTING

Academic medical center.

PATIENTS

Ninety American Society of Anesthesiologists physical status 1 and 2 children scheduled for cataract surgery.

INTERVENTIONS

Patients were randomized into 3 groups: group D1, group D2, and saline group (group C), in which the children received 1 or 2 μg/kg of intranasal DEX or saline, respectively, and each group comprises 30 patients.

MEASUREMENTS

The mask induction score and the incidences of postoperative emergence agitation evaluated by the Pediatric Anesthesia Emergence Delirium scale were assessed. The emergence time, postanesthesia care unit (PACU) stay time, and any adverse events were recorded.

MAIN RESULTS

The mask induction scores were significantly higher in the saline group than those in the D1 and D2 groups (P<.001). The incidences of emergence agitation in the D1 and D2 groups were significantly lower than that in the saline group (7/30 in group D1 and 3/30 in group D2 vs 24/30 in group C, P<.001). The emergence time and PACU stay time were comparable among the 3 groups (P>.05). The emergence time and PACU stay time did not differ significantly in DEX-treated groups as compared with the saline group; there were no differences between 1- and 2-μg/kg groups. None of the patients exhibited significant clinical complications.

CONCLUSION

Intranasal DEX (1 or 2 μg/kg) dose independently improves the incidences of mask acceptance and prevents the incidences of postoperative emergency agitation mainly from sevoflurane without delaying the emergency time or inducing severe adverse events.

Intrathecal Dexmedetomidine and Fentanyl as Adjuvant to Bupivacaine on Duration of Spinal Block in Addicted Patients

Background:

Addicted patients have innate tolerance to local anesthetics in both neuraxial and peripheral blocks. Dexmedetomidine (Dex) is a highly selective α₂ adrenergic receptor agonist used as additive to increase quality and duration of peripheral nerve blocks.

Objectives:

The current study aimed to compare the effect of dexmedetomidine and fentanyl additives on bupivacaine to prolong the duration of block and minimizing side effects.

Patients and Methods:

Patients were candidates for elective surgery less than three hours of lower abdomen or lower extremities surgeries. Patients were randomly allocated to receive dexmedetomidine 5 µg added to 12.5 mg (2.5 mL) of 0.5% hyperbaric bupivacaine (DEX group), or 25 µg (0.5 mL) fentanyl added to 12.5 mg (2.5 mL) of 0.5% hyperbaric bupivacaine (F group) or only 12.5 mg of 0.5% hyperbaric bupivacaine. Data were recorded based on sensory block. Motor block was tested using modified Bromage scale every 30 minutes until the end of block. Time to return of sensory block to 4 dermatomes below and time to return of Bromage scale to 0 were recorded. All vital measurements (oxygen saturation, heart rate, electrocardiogram, and non-invasive blood pressure) were performed at 0, 30, 60, 90, 120 and 180 minutes in all three groups of the study. Group DEX received dexmedetomidine additive and group F received fentanyl additive and group C (control) received normal saline.

Results:

Totally, 84 patients were randomly divided into three groups of 28 patients. Onset of sensory block in DEX group was significantly lower than those of fentanyl (P = 0.012) and control groups (P = 0.001). Duration of sensory block was significantly longer in DEX group compared to Fentanyl (P = 0.043) and control (P = 0.016) groups. Duration of motor block in the DEX group was significantly longer than those of the fentanyl (P = 0.014) and control groups. Heart rate and mean arterial pressure were significantly higher in the DEX group at 30, 60, 90,120, and 180 minutes compared to those of the other two groups (P < 0.05).

Conclusions:

Dexmedetomidine added to bupivacaine in spinal anesthesia is more effective to increase duration of block, providing more appropriate sedation and less postoperative pain scale and post-operative nausea and vomiting (PONV) compared to fentanyl additive.

Emergence agitation prevention in paediatric ambulatory surgery: A comparison between intranasal Dexmedetomidine and Clonidine

Objective:

Emergence agitation (EA), a short-lived, self-limiting phenomenon, arises frequently after the use of inhalational agents and hampers the implementation of pediatric ambulatory surgery in spite of using so many drugs with variable efficacy.

Methods:

In this prospective, double-blinded, parallel group study (2008–2009), 80 children of both sex aged 3–7 years, with American Society of Anesthesiologists (ASA) physical status grade I-II, undergoing sevoflurane-based general anesthesia for elective day care surgery were randomly assigned into groups C or D. Group C received 4 μg/kg intranasal clonidine, whereas group D received 1 μg/kg intranasal dexmedetomidine, 45 min before induction of anesthesia. In postanesthesia care unit (PACU), the incidence of EA was assessed with Aonos four-point scale and the severity of EA was assessed with pediatric anesthesia emergence delirium scale upon admission (T0), after 5 min (T5), 15 min (T15), and 25 min (T25). Extubation time, emergence time, duration of PACU stay, dose and incidence of fentanyl use for pain control were noted.

Findings:

Based on comparable demographic profiles, the incidence and severity of EA were significantly lower in group D as compared to group C at T0, T5, T15, and T25. But time of regular breathing, awakening, extubation, and emergence were significantly delayed in group D than C. The number and dose of fentanyl used in group C were significantly higher than group D. PACU and hospital stay were quite comparable between groups.

Conclusion:

Intranasal dexmedetomidine 1 μg/kg was more effective than clonidine 4 μg/kg in decreasing the incidence and severity of EA, when administered 45 min before the induction of anesthesia with sevoflurane for pediatric day care surgery. Dexmedetomidine also significantly reduced fentanyl consumption in PACU.

Preoperative anxiety management, emergence delirium, and postoperative behavior

Preoperative anxiolysis is important for children scheduled for surgery. The nature of the anxiety depends on several factors, including age, temperament, past hospitalizations, and socioeconomic and ethnic backgrounds. A panoply of interventions effect anxiolysis, including parental presence, distraction, and premedication, although no single strategy is effective for all ages. Emergence delirium (ED) occurs after the use of sevoflurane and desflurane in preschool-aged children in the recovery room. Symptoms usually last approximately 15 minutes and resolve spontaneously. The Pediatric Anesthesia Emergence Delirium scale is used to diagnose ED and evaluate therapeutic interventions for ED such as propofol and opioids.

Psychopharmacology for medically ill adolescents

Medically ill adolescents are at increased risk for psychological distress and/or functional impairment. However, there are few research studies examining the optimal psychiatric treatments for this population. Psychiatric medication recommendations are largely based on studies of youth with a primary psychiatric disorder, adult studies, hypothesized mechanisms of action, and/or clinical experience. This paper provides evidence-informed recommendations for the psychopharmacological treatment of acutely medically ill adolescents suffering from significant psychological distress and/or functional impairment. Representing the most common problems among medically ill adolescents that are treated with psychiatric medications, recommendations are provided for anxiety and depression; iatrogenic medical trauma, inadequate sleep and insomnia; and, delirium.