The prevalence of emergence delirium and its associated factors among children at a postoperative unit: A retrospective cohort at a Middle Eastern hospital

BACKGROUND

Emergence delirium (ED) has been reported among children at a postoperative setting, which delays their recovery and exposes them to traumas. The aim of this study was to determine the prevalence of ED and its associated factors among children who underwent surgeries at a major tertiary healthcare facility in Saudi Arabia.

MATERIALS AND METHODS

Between March and August 2018, a retrospective cohort study was conducted based on a review of 413 medical charts of children (<14 years) who underwent an elective/nonemergency surgery and then were admitted to a Post Anesthesia Care Unit. Patient and surgery-related characteristics were analyzed as potential factors associated with ED. The anxiety level was assessed preoperatively using the Modified Yale Preoperative Anxiety Scale (four domains), while the ED was detected after surgery using the Watcha scale (child is agitated and thrashing around).

RESULTS

The leading surgery category was ear, nose, and throat surgeries [184 (44.6%)] and dental surgeries [109 (26.4%)]. Almost one-third received only general anesthesia (31.2%), while 271 (68.8%) received an additional regional block/skin infiltrate. The anxiety domains preop showed that the percentage mean score ± standard deviation of expression of emotions was 37.1 ± 21.6, apparent arousal 33.7 ± 20.4, activeness 30.1 ± 13.5, and vocalization 26.9 ± 20.3. The prevalence of ED among children who underwent surgeries during the 6-month period was 23 (6.6%). Almost 18.8% of those who received opioid analgesics (fentanyl alone) developed ED, while 12% of those who received both opioid and nonopioid analgesics (fentanyl/paracetamol) developed ED. ED was significantly associated with longer recovery duration 69.5 + 27.1 min, P = 0.007. Binary logistics regression analysis showed that participants who did not receive Precedex were adj. odds ratio = 10.3 (2.4-48.9) times more likely to develop ED, compared with those who received it, adj. P = 0.003. Lower preoperative scores of expression of emotions and higher scores of apparent arousal were significantly associated with ED, adj. P = 0.035 and adj. P = 0.023, respectively.

CONCLUSION

ED appears to be inevitable in postoperative settings. It is crucial to address any preoperative anxiety assessment as it is associated with ED. Anxiety remains a modifiable factor that can be managed, as well as to the administration of Precedex and adjunct analgesic treatments.

A randomized control trial using intraoperative dexmedetomidine during Roux-en-Y gastric bypass surgery to reduce postoperative pain and narcotic use

BACKGROUND

Dexmedetomidine (DMET), a selective a2-adrenergic agonist, is an opioid-sparing adjuvant sedative that avoids respiratory depression and has been shown to be beneficial in bariatric surgery patients. Although benefit has been shown, prior studies have not evaluated the pain control effects of a single intraoperative bolus.

OBJECTIVES

To evaluate the postoperative effects of a single intraoperative dose of DMET.

SETTINGS

University Hospital, United States.

METHODS

This is a prospective, randomized, double-blinded study registered with clinicaltrials.gov (#NCT02604940). Patients undergoing laparoscopic Roux-en-Y gastric bypass surgery were randomized and given either a placebo or an intraoperative DMET bolus, where 1 mg/kg was delivered over 10 minutes at the time of surgical closure. Measured outcomes included the following: postoperative pain scores, patient-controlled analgesia (PCA) opioid consumption, PCA demand bolus attempts, duration of postanesthesia care unit (PACU) stay, and vital signs. Descriptive statistics were recorded as frequencies and compared using Χ² analysis, and a Welch's 2-sample t test was used to compare continuous variables.

RESULTS

Forty-six participants undergoing laparoscopic Roux-en-Y gastric bypass surgery were randomized into placebo (n = 20) or DMET (n = 26) groups. There were no statistical differences in age (45.1 versus 43.2 yr, P = .522), sex (80% versus 81% female, P = .948), and body mass index (46.1 versus 45.6 kg/m², P = .818) between the 2 groups. There were no statistically significant differences in vital signs (heart rate, blood pressure, oxygen saturation, and respiration rate) between DMET and placebo groups in the preoperative and intraoperative period. During the initial 4 hours in the PACU postoperatively, mean heart rate (70 ± 12 versus 86 ± 14, P < .001), systolic blood pressure (107 ± 17 versus 148 ± 16, P < .001), and diastolic blood pressure (56 ± 15 versus 79 ± 13, P < .001) were significantly lower in the DMET-treated group compared with placebo. During the initial 4 hours in the PACU, mean self-reported pain scores were significantly lower in the DMET-treated group (3.6 ± 2.8) compared with the placebo group (6.7 ± 3; P = .005). The lower pain scores occurred with no significant difference in the mean opioid dosage received in the PACU between DMET-treated (2.66 ± 2.02 mg) and placebo (3.7 ± 2.3 mg; P = .09) groups. Also, there was no statistically significant difference in the total number of PCA attempts for opioids between the DMET-treated and placebo groups (P = .49).

CONCLUSIONS

A single bolus of DMET (1 mg/kg delivered over 10 min) administered at the time of surgical closure did not reduce immediate PACU usage of opioids but significantly reduced reported pain scores and caused a significant decrease in the number of attempts made by patients; this is a trend of decreased attempts over time (P = .04) in the DMET group. The trend of the mean total medication used over time indicates that there is neither an increasing nor decreasing trend for the DMET group, but there is an increasing trend in the total used over time for the placebo group. There was no statistically or clinically significant bradycardia, hypotension, hypoxia, respiratory depression intraoperative duration, or PACU stay. Reduced single bolus dosing of DMET required for analgesia in bariatric surgery patients is optimal from physiologic, level of care, and cost perspectives.

Population Pharmacokinetics of Dexmedetomidine in Infants

Despite limited pharmacokinetic (PK) data, dexmedetomidine is increasingly being used off-label for sedation in infants. We aimed to characterize the developmental PK changes of dexmedetomidine during infancy. In this open-label, single-center PK study of dexmedetomidine in infants receiving dexmedetomidine per clinical care, ≤10 blood samples per infant were collected. A set of structural PK models and residual error models were explored using nonlinear mixed-effects modeling in NONMEM. Covariates including postmenstrual age (PMA), serum creatinine, and recent history of cardiac surgery requiring cardiopulmonary bypass were investigated for their influence on PK parameters. Univariable generalized estimating equation models were used to evaluate the association of hypotension with dexmedetomidine concentrations. A total of 89 PK samples were collected from 20 infants with a median PMA of 44 weeks (range, 33-61). The median maximum dexmedetomidine infusion dose during the study period was 1.8 μg/(kg·h) (0.5-2.5), and 16/20 infants had a maximum dose >1 μg/(kg·h). A 1-compartment model best described the data. Younger PMA was a significant predictor of lower clearance. Infants with a history of cardiac surgery had ∼40% lower clearance compared to those without a history of cardiac surgery. For infants with PMA of 33 to 61 weeks and body weight of 2 to 6 kg, the estimated clearance and volume of distribution were 0.87 to 2.65 L/(kg·h) and 1.5 L/kg, respectively. No significant associations were found between dexmedetomidine concentrations and hypotension. Infants with younger PMA and recent cardiac surgery may require relatively lower doses of dexmedetomidine to achieve exposure similar to older patients and those without cardiac surgery.

Intranasal Dexmedetomidine as a Sedative for Pediatric Procedural Sedation

OBJECTIVE

This study seeks to evaluate the efficacy and safety of intranasal (IN) dexmedetomidine as a sedative medication for non-invasive procedural sedation.

METHODS

Subjects 6 months to 18 years of age undergoing non-invasive elective procedures were included. Dexmedetomidine (3 mcg/kg) was administered IN 40 minutes before the scheduled procedure time. The IN dexmedetomidine cohort was matched and compared to a cohort of 690 subjects who underwent sedation for similar procedures without the use of dexmedetomidine to evaluate for observed events/interventions and procedural times.

RESULTS

One hundred (92%) of the 109 included subjects were successfully sedated with IN dexmedetomidine. There were no significant differences in the rate of observed events/interventions in comparison to the non-dexmedetomidine cohort. However, the IN dexmedetomidine group had a longer postprocedure sleep time when compared to the non-dexmedetomidine cohort (p < 0.001), which had a significant effect on recovery time (p = 0.024). Also, the dexmedetomidine cohort had longer procedure time and total admit time (p < 0.001 and p = 0.037, respectively).

CONCLUSIONS

IN dexmedetomidine may be used for non-invasive pediatric procedural sedation. Subjects receiving IN dexmedetomidine had a similar rate of observed events/interventions as the subjects receiving non-dexmedetomidine sedation, with the exception of sleeping time. Also, patients sedated with IN dexmedetomidine had longer time to discharge, procedure time, and total admit time in comparison to other forms of sedation.

General anesthesia in a patient with citrullinemia using Precedex as an adjunct to prevent delayed emergence

Citrullinemia type I is a rare autosomal recessive genetic condition that causes reduced activity of the enzyme, argininosuccinate synthase, which is needed for proper urea metabolism. The end result is hyperammonemia which can cause life-threatening neurologic symptoms and global developmental delay. Previous case reports of the anesthetic management of patients with citrullinemia describe delayed recovery possibly related to elevated ammonia levels postoperatively or choice of intraoperative anesthetics which have included narcotics. In this case report, we present the anesthetic management of a 16-year-old adolescent girl with citrullinemia type I undergoing a vagus nerve stimulator revision. We used the α-2-adrenergic agonist, dexmedetomidine, as an adjunct to avoid narcotics to prevent delayed emergence. She was admitted for hydration the night before the procedure and had a baseline ammonia level of 33 μmol/L (reference, 9-33 μmol/L). Anesthetic maintenance consisted of 2% sevoflurane, dexmedetomidine 0.5 μg/kg per hour, and intravenous acetaminophen given toward the conclusion of the surgery. The patient awoke immediately at the end of the procedure and was extubated in the operating room. Postprocedure, her ammonia level was less than 9 μmol/L. She appeared to be free of pain, was tolerating gastric tube feeds postprocedure, and was discharged to home on the day of surgery. Effective management of ammonia levels in this patient using preoperative hydration and dexmedetomidine as an adjunct to general anesthesia may have helped to prevent delayed emergence.