Clonidine for preventing emergence agitation in infants (PREVENT AGITATION II): Protocol and statistical analysis plan.

BACKGROUND: Emergence agitation is a common clinical condition in children. Symptoms pertaining to the spectrum of early postoperative negative behavior typically occur upon emergence from anesthesia. Clonidine is an effective adjunctive agent for the prevention of emergence agitation in children, but evidence in the smallest age groups is sparse We aim to investigate the efficacy and safety of an intraoperative bolus of intravenous clonidine for preventing emergence agitation in children 3-12 months of age. METHODS: This is a randomized, placebo-controlled, double-blind trial. We will enroll 320 patients aged 3-12 months who have been scheduled for general anesthesia maintained with sevoflurane and opioid. The randomization is parallel and stratified by age group, sex, and site. The investigational medicinal product will be administered intravenously ~20 min before the anticipated end of the surgical procedure. The intervention is clonidine 3 µg/kg and placebo is isotonic saline in a corresponding volume. RESULTS: The primary outcome is the incidence of emergence agitation as assessed on the Watcha scale, that is, any Watcha score >2 during participants' stay in the postanesthetic care unit. Secondary outcomes are the proportion of participants with postoperative pain, with postoperative nausea and vomiting, and a composite safety outcome. Statistical analysis will be conducted according to the Statistical Analysis Plan with the intention-to-treat population for our primary analyses. CONCLUSION: The PREVENT AGITATION II trial will contribute valuable knowledge on efficacy for the prevention of emergence agitation and safety in infants.

Waking Up in Pain: a prospective unselected cohort study of pain in 3702 patients immediately after surgery in the Danish Realm.

BACKGROUND: Acute and persistent pain after surgery is well described. However, no large-scale studies on immediate postoperative pain in the operating room (OR) exist, hindering potential areas of research to improve clinical outcomes. Thus, we aimed to describe the occurrence and severity of immediate postoperative pain in a large, unselected cohort. METHODS: This was a prospective cohort study, encompassing all procedures in 31 public hospitals in the Danish Realm, during a 5-day period including the weekend. Data on procedures and anesthesia were collected and the main outcome was occurrence of moderate or severe pain in the OR. Secondary outcomes included pain, sedation and nausea in the OR or during the first 15 min in the postanesthesia care unit (PACU) including relevant risk factors. Descriptive and logistic regression statistics were used. RESULTS: A total of 3675 procedures were included for analysis (87% inclusion rate). Moderate or severe pain occurred in 7.4% (95% CI 6.5% to 8.3%) of cases in the OR immediately after awakening, rising to 20.2% in the OR and/or PACU. Large intraprocedure and interprocedure variations occurred (0.0%-37.5%), and in 20% of cases with epidural-general anesthesia patients experienced moderate or severe pain. Independent risk factors were female sex, younger age, preoperative pain, daily opioid use and major surgical procedures. CONCLUSION: Moderate or severe pain in the immediate postoperative phase occurred in 20% of all cases with procedure and anesthesiological technique variations, suggesting a need for identification of relevant procedure-specific risk factors and development of preventive treatments. TRIAL REGISTRATION NUMBER: RoPR ID 43191.

Pharmacokinetics of an intravenous bolus dose of clonidine in children undergoing surgery.

BACKGROUND: Clonidine is used off-label in children but only limited pediatric pharmacokinetic data are available for intravenously administered clonidine. OBJECTIVES: To determine pharmacokinetic parameter estimates of clonidine in healthy children undergoing surgery and to investigate age-related differences. Furthermore, to investigate possible pharmacokinetic differences of clonidine between this group of children and a cohort with cardiac diseases. METHODS: In a randomized placebo-controlled trial (The PREVENT AGITATION trial), blood samples for clonidine pharmacokinetic analysis were collected in a proportion of the enrolled patients. Healthy children with ASA score 1-2 in the age-groups 1 to <2 years and 2-5 years were randomized for blood sampling. Clonidine was administered as a single intravenous bolus of 3 µg/kg intraoperatively. Blood samples were drawn at baseline, 5, 10, 15, 30, 60 minutes after dosing and additionally every hour until discharge from the PACU. Clonidine analysis was performed on liquid chromatography-mass spectrometry. RESULTS: Data form eighteen children were available for pharmacokinetic analysis (ASA I; male/female: 17/1; age: 1-5 years; weight 8.7-24 kg). Population parameter estimates for the 2-compartment model were similar to previous published data for children who underwent cardiac surgery. A pooled analysis including data from 59 children indicated clearance of 14.4 L h-1  70 kg-1 and volume of distribution of 192.6 L 70 kg-1 . No age-related pharmacokinetic differences and no difference in time from administration of study medication to awakening were found. Children 1 to <2 years had a shorter PACU stay than children 2-5 years (mean difference 17% 95% CI:3%-34%, P = .02). CONCLUSION: Pharmacokinetic parameter estimates were similar for children undergoing general surgery and cardiac surgery given a single dose of intravenous clonidine. These results indicated that no dose reduction is needed in children aged 1 to <2 years compared with those 2-5 years, which was supported by pharmacodynamic observations.