Isoelectric Electroencephalography in Infants and Toddlers during Anesthesia for Surgery: An International Observational Study

Abstract

Background Intraoperative isoelectric electroencephalography (EEG) has been associated with hypotension and postoperative delirium in adults. This international prospective observational study sought to determine the prevalence of isoelectric EEG in young children during anesthesia. We hypothesized that the prevalence of isoelectric events would be common worldwide and associated with certain anesthetic practices and intraoperative hypotension. Methods. Fifteen hospitals enrolled patients age ≤ 36 months for surgery using sevoflurane or propofol anesthetic. Frontal 4-channel EEG was recorded for isoelectric events. Demographics, anesthetic, emergence behavior, and Pediatric Quality of Life (PedsQL) variables were analyzed for association with isoelectric events. Results. Isoelectric events occurred in 32% (206/648) of patients, varied significantly among sites (9-88%), and were most prevalent during pre-incision (117/628, 19%) and surgical maintenance (117/643, 18%). Isoelectric events were more likely with [odds ratio-OR (95% confidence interval-CI)] infants < 3 months [4.4 (2.57-7.4) p<0.001], endotracheal tube use [1.78 (1.16-2.73) p=0.008], propofol bolus for airway placement after sevoflurane induction [2.92 (1.78-4.8) p<0.001], and less likely with use of muscle relaxant for intubation [0.67 (0.46-0.99) p=0.046]. Expired sevoflurane was higher in patients with isoelectric events [mean difference (95% CI)] during pre-incision [0.2% (0.1, 0.4) p=0.005] and surgical maintenance [0.2% (0.1, 0.3) p=0.002]. Isoelectric events were associated with moderate (8/12, 67%) and severe hypotension (11/18, 61%) during pre-incision [OR: 4.6 (1.30-16.1) p=0.018; 3.54 (1.27, 9.9) p=0.015] and surgical maintenance [OR: 3.64 (1.71-7.8) p=0.001; 7.1 (1.78- 28.1) p=0.005], and lower PedsQL scores [median of differences (95% CI)] at baseline in patients 0-12 [-3.5 (-6.2, -0.7) p=0.008] and 25-36 months [-6.3 (-10.4, -2.1) p=0.003] and 30-day follow-up in 0-12 months [-2.8 (-4.9, 0) p=0.036]. Isoelectric events were not associated with emergence behavior or anesthetic (sevoflurane vs propofol). Conclusions. Isoelectric events were common worldwide in young children during anesthesia and associated with age, specific anesthetic practices, and intraoperative hypotension.

Depth of anesthesia, temperature, and postoperative delirium in children and adolescents undergoing cardiac surgery

“…Emergence agitation occurs usually within the first 30 min after anesthesia, and is characterized by combativeness, excitation, disorientation, and inconsolability [ 33 ]. In a single- and in a multi-center study in children up to 37 or 36 months of age, respectively, isoelectric events during anesthesia were not associated with emergence behavior [ 34 , 35 ]. After anesthesia with the inhalation anesthetic sevoflurane, which was given in our study, emergence delirium occurs particularly frequently in children [ 36 ].…”

Association of volatile anesthesia exposure and depth with emergence agitation and delirium in children: Prospective observational cohort study

“…Indeed, the BIS represents the level of consciousness under anesthesia, which has proven controversial among anesthesiologists ( 31 , 32 ). Intraoperative isoelectric electroencephalography (EEG) has been considered to be associated with delirium in many studies ( 33 , 34 ), however, two recent studies of isoelectric EEG in toddlers or older adults showed that it was not independently correlated with ED ( 35 , 36 ). More high-quality RCT trials are needed to confirm BIS- or EEG-guided anesthesia.…”

Monitoring anesthesia depth with patient state index during pediatric surgery

“…At discharge from operatory room, patients showed a median PAED score of 11. [10][11][12] The presence of a BS episode was not associated with the PAED levels (OR 1.58, 95% CI 0.14-16.74, p = .18). Shorter surgeries were associated with higher PAED levels (r: −.36, 95% CI −0.55 to −0.13, p = .0025), and lower PSI at extubation (r: −.46, 95% CI −0.62 to −0.27, p < .0001).…”

“…4,9 This is because this technology is not routinary applied in pediatric anesthesia and the use of dedicated pediatric devices is still on a development phase. 4,[9][10][11][12] However, if feasible, a pEEG-guided anesthesia might contribute to optimally target anesthesia depth. The Root® and SedLine® monitor (Masimo Inc.) and the novel SedLine pediatric sensors (Masimo Inc.) can be applied as a pEEG monitor in children.…”