Three Adjuncts to Anesthesia to Prevent Emergence Agitation in Pediatric Dentistry; a Pilot Study
W Mckay, K Derdall, M Brahmania, C Nagle, I Hamilton, M Teekasingh
Keywords
emergence agitation, pediatric anesthesia, pedodontics, vomiting prophylaxis
Citation
W Mckay, K Derdall, M Brahmania, C Nagle, I Hamilton, M Teekasingh. Three Adjuncts to Anesthesia to Prevent Emergence Agitation in Pediatric Dentistry; a Pilot Study. The Internet Journal of Anesthesiology. 2010 Volume 29 Number 1.
Abstract
Implication Statement
Many children require dental care under general anesthesia. Post-operative emergence agitation, vomiting, pain, or distress is upsetting for child and parent, and can result in complications. This is a pilot study of anesthetic adjuncts with diverse properties given to promote smooth awakening. No promising agents were found.
Introduction
Small children with extensive carious dental disease require dental care under general anesthesia (GA) that often includes pulpotomies, stainless steel crowns and extractions. Although they could be expected to have little or no post-operative pain, aside from minor gum irritation from clamps, rubber dams, etc. their post-operative course is often marred by vomiting (35%),1 prolonged crying, and emergence agitation (EA - 18%).2 A number of pharmacologic adjuncts to general anesthesia have been systematically studied, with mixed results.3-9,10,11
Children of the age (3 to 6years) commonly treated for carious disease under GA cannot articulate symptoms clearly. We wondered if they might be distressed by nausea, pain, or intra-oral post-traumatic edema causing abnormal tissue sensation perceived as discomfort.12 We hypothesised that intravenous granisetron (G) for nausea, morphine (M) for pain, dexamethasone (D) for tissue edema), or combination (C) of all three, would result in smoother emergence from dental care under general anesthesia in children than saline placebo, as measured by episodes of EA, vomiting, crying, appearing to suffer pain, or seeming distressed.
EA is a common side effect of general anesthesia in children that is not well understood, and was the primary outcome.13,14,15 We wondered if decreasing the perception of discomfort could ameliorate the sensations listed above to decrease the incidence of EA. The study was intended as a pilot, to guide a further dose-ranging study of the most promising of the drugs tried, and to allow for sample size calculation. In addition, we wished to document other symptoms such as pain, vomiting, and behaviour indicating distress, as a guide to providing informed consent to future patients.
Method
The study consists of two parts. It was begun with halothane (Hal) as the anesthetic vapour but changed to sevoflurane (Sev) after recruiting 105 subjects because halothane was no longer available in Canada. A safety monitoring committee consisting of the non-assessing authors
At a follow-up telephone call the next day, we enquired about the child's wellbeing, pain, behaviour, vomiting, and any other complications using a standard script. We use the term “distress” to describe a child who was not behaving normally and appeared to be upset, unhappy, and/or uncomfortable at the home follow-up call.
Continuous variables were analysed by ANOVA, categorical variables by Chi-square, and ordinal data by ANOVA-on–ranks with alpha = 0.05. Counts were analysed by approximation to a Poisson distribution.19 Confidence intervals of proportions included continuity correction and were calculated with an on-line calculator.20, 21 The strength of association of the PAEDS with EA was analysed by logistic regression. Because it is a pilot study, no corrections were made for multiple comparisons.22 Analysis was two-tailed and by intention to treat. Statistical analysis was done using Sigmastat® version 3.11 (Systat Software Inc, Chicago IL, USA).
Results
Disposition of subjects is given in the CONCORD22 diagram, Figure 1. Demographics are listed in Table 1. The 38 subjects lost to next-day follow-up could not be reached by telephone. While 84% of the 167 parents responding to telephone follow-up reported completely normal behaviour next day, 11/167 (6.6% [3.5 to 11.8%]) reported symptoms more severe than merely listlessness or lack of appetite.
Hal: halothane, Sev: sevoflurane, S: saline, N: narcotic (morphine or meperidine), G: granisetron, D: dexamethasone, C: combination.
*significantly different from other treatments in the row
Hal: halothane, Sev: sevoflurane, S: saline, N: narcotic (morphine or meperidine), G: granisetron, D: dexamethasone, C: combination.
The PAEDS scoring system18 (see Figure 2) was highly predictive of EA as we measured it (odds ratio of PAEDS score >10 predicting EA by our scoring system: 2.1[1.6 to 2.8]; odds ratio of PAEDS score > 15, 12.3[4.3 to 47.2]; linear R = 0.7; P < 0.0001 for both constant and coefficient).
Figure 4
*significantly different from other treatments in the row
Discussion
Almost everyone approached agreed to be in the study. Thus, such studies are feasible in this population. Thirty-eight subjects were lost to home follow-up. Many of our subjects live in remote Northern villages with limited telephone service, and rely on friends and relatives for use of a telephone. Thus, while all had given us a telephone number, for some, the telephone was not in their home, and they were not easily found.
Acknowledgements
This study was funded by a grant from The Royal University Hospital Foundation. We gratefully acknowledge the expert and efficient work of Sally Tufts, RN, who conducted much of the recruitment and data collection.