Impact of sedation and anesthesia on the rectoanal inhibitory reflex in children.
OBJECTIVE
The study objective was to determine whether the rectoanal inhibitory reflex (RAIR) can be elicited during limited anorectal manometry (ARM) performed under general anesthesia (GA).


METHODS
In this retrospective study, patients with intractable constipation who underwent ARM under GA from November 1999 to March 2002 were evaluated. Rectal biopsy specimens were examined for the presence of ganglion cells.


RESULTS
Eighty consecutive patients aged 5 months to 16 years were evaluated. Three patients with Hirschsprung disease were excluded from analysis. Ganglion cells were found in rectal biopsy specimens from 76 patients. RAIR was positive in 69 (90%) and negative in 8 (10%). Forty-five patients received preoperative medications: midazolam (n = 36), midazolam + atropine (n = 3), atropine (n = 1), midazolam + glycopyrrolate (n = 3), and glycopyrrolate (n = 2). Different combinations of general anesthetic medications were used. Ten patients received neuromuscular blockers. The use of preoperative midazolam or atropine did not affect the presence or absence of RAIR; however, the proportion of patients with negative RAIR was higher in those receiving glycopyrrolate (P = 0.007) than in those receiving other medications. There was no significant difference in the effect of the general anesthetic agents or neuromuscular blockers used on the presence or absence of RAIR.


CONCLUSIONS
The rectoanal inhibitory reflex in children can be elicited even when anorectal manometry is performed under general anesthesia. Glycopyrrolate, an anticholinergic, appears to inhibit the demonstration of the RAIR.
Pfefferkorn
Marian D
MD
Indiana University School of Medicine, James Whitcomb Riley Hospital for Children, Indianapolis, Indiana 46202-5225, USA. mdelrosa@iupui.edu
Croffie
Joseph M
JM
Corkins
Mark R
MR
Gupta
Sandeep K
SK
Fitzgerald
Joseph F
JF
D000759:Adjuvants, Anesthesia / Q000008:administration & dosage / Q000009:adverse effects; D000293:Adolescent; D001003:Anal Canal; D000768:Anesthesia, General / Q000009:adverse effects* / Q000379:methods; D001285:Atropine; D002648:Child; D002675:Child, Preschool; D003248:Constipation / Q000175:diagnosis* / Q000209:etiology; D003672:Defecation; D003937:Diagnosis, Differential; D005260:Female; D006024:Glycopyrrolate; D006627:Hirschsprung Disease / Q000175:diagnosis / Q000473:pathology; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000009:adverse effects*; D007223:Infant; D008297:Male; D008365:Manometry / Q000379:methods*; D008874:Midazolam; D009466:Neuromuscular Blocking Agents / Q000008:administration & dosage / Q000009:adverse effects; D012007:Rectum; D012018:Reflex / Q000187:drug effects* / Q000502:physiology; D012189:Retrospective Studies
D000759:Adjuvants, Anesthesia; D006993:Hypnotics and Sedatives; D009466:Neuromuscular Blocking Agents; D001285:Atropine; D008874:Midazolam; D006024:Glycopyrrolate