Anorectal manometry with and without ketamine for evaluation of defecation disorders in children.
BACKGROUND
Anorectal manometry (ARCM) provides valuable information in children with chronic constipation and fecal incontinence but may not be tolerated in the awake child. This study aimed to evaluate the effect of ketamine anesthesia on the assessment of anorectal function by manometry and to evaluate defecation dynamics and anal sphincter resting pressure in the context of pathophysiology of chronic functional (idiopathic) constipation and soiling in children.


METHODS
This was a prospective study of children who were investigated for symptoms of chronic constipation and soiling between April 2001 and April 2004. We studied 52 consecutive children who had awake ARCM, biofeedback training and endosonography (awake group) and 64 children who had ketamine anesthesia for ARCM and endosonography (ketamine group). We age matched 31 children who had awake anorectal studies with 27 who had ketamine anesthesia.


RESULTS
The children in awake and ketamine groups were comparable for age, duration of bowel symptoms and duration of laxative treatments. ARCM profile was comparable between the awake and the ketamine groups with regard to anal sphincter resting pressure, rectal capacity, amplitude of rectal contractions, frequency of rectal and IAS contractions and functional length of anal canal. Of 52 children who had awake ARCM, dyssynergia of the EAS muscles was observed in 22 (42%) and median squeeze pressure was 87mm Hg (range 25-134). The anal sphincter resting pressure was non-obstructive and comparable to healthy normal children. Rectoanal inhibitory reflex was seen in all children excluding diagnosis of Hirschsprung disease.


CONCLUSIONS
Ketamine anesthesia does not affect quantitative or qualitative measurements of autonomic anorectal function and can be used reliably in children who will not tolerate the manometry while awake. Paradoxical contraction of the EAS can only be evaluated in the awake children and should be investigated further as the underlying cause of obstructive defecation in patients with chronic functional constipation and soiling.
Evelina London Children's Hospital, Guy's and St Thomas' National Health Service Foundation Trust, London, UK. Electronic address: ali.keshtgar@gstt.nhs.uk.
A S
AS
Keshtgar
Chelsea and Westminster, National Health Service Foundation Trust, London, UK.
M S
MS
Choudhry
Evelina London Children's Hospital, Guy's and St Thomas' National Health Service Foundation Trust, London, UK.
D
D
Kufeji
Barts and the London National Health Service Trust, London, UK.
H C
HC
Ward
Evelina London Children's Hospital, Guy's and St Thomas' National Health Service Foundation Trust, London, UK.
G S
GS
Clayden
D000293:Adolescent; D001003:Anal Canal / Q000503:physiopathology; D000700:Analgesics; D001676:Biofeedback, Psychology; D002648:Child; D002675:Child, Preschool; D003248:Constipation / Q000503:physiopathology*; D003672:Defecation / Q000502:physiology*; D019160:Endosonography; D005242:Fecal Incontinence / Q000503:physiopathology*; D005260:Female; D006627:Hirschsprung Disease; D006801:Humans; D007649:Ketamine; D054368:Laxatives / Q000008:administration & dosage; D008297:Male; D008365:Manometry / Q000379:methods*; D009119:Muscle Contraction; D011312:Pressure; D011446:Prospective Studies
D000700:Analgesics; D054368:Laxatives; D007649:Ketamine
Anorectal; Biofeedback; Constipation; Endosonography; Ketamine; Manometry