INTESTINAL OBSTRUCTION

INTESTINAL OBSTRUCTION
A. Diagnosis and preoperative management:
•Intestinal obstruction should be suspected with maternal history of
polyhydramnios, large amount (>20 mL) of gastric fluid at birth, bilious or nonbilious
emesis, or progressive abdominal distension.
•Common causes include duodenal, jejunal, ileal, or colonic atresia, malrotation
with mid gut volvulus, meconium ileus with associated cystic fibrosis, meconium
plug, Hirschsprung’s disease, imperforate anus, and hypoplastic left colon.
•Infants with bowel atresia may pass meconium.
•The higher the obstruction, the more prominent is the vomiting. The lower the
obstruction, the more prominent is the distension.
•Make infant NPO, start IV, and monitor electrolytes, urine output and weight.
•Place Replogle tube to continuous suction and measure output.
•Obtain KUB looking for
-“double bubble” sign of duodenal atresia. If present, no further GI workup is
needed and patient should go to surgery when stable.
-multiple dilated loops of bowel indicating a more distal obstruction
-intraperitoneal calcifications suggestive of perforation with meconium ileus
-air throughout bowel to the rectum suspicious for Hirschsprung’s disease
-bubbly-appearing stool filling the bowel suggestive of meconium ileus and
cystic fibrosis
•Upper GI contrast study (with dilute Hypaque™or Gastrograffin™) may be
required to assess for malrotation and possible volvulus.
•Contrast enema using Gastrografin™ or dilute Hypaque™ may be done to identify
an area of obstruction or to relieve meconium plug or meconium ileus.
•Suspect acute volvulus secondary to malrotation if the baby has signs of shock,
metabolic acidosis or peritonitis. If there are signs suggesting volvulus,
emergency operation is indicated since gut viability may be threatened.
•Suspect Hirschsprung’s disease with repeated episodes of abdominal distension
or very delayed passage of meconium. Diagnosis can be made with suction rectal
biopsy. If no ganglion cells are seen, a surgical biopsy will confirm the diagnosis.
•Infants with Hirschsprung’s disease are at risk for development of fatal toxic
megacolon until the bowel has been decompressed by corrective surgery or
colostomy. Surgeons may choose to decompress initially with rectal irrigation.
This is different from simple enemas.
•Imperforate anus may be the sole abnormality or may be part of the VATER
association. Look carefully for evidence of recto-vaginal, recto-urethral or
perineal fistula. Ultrasound may help determine if the defect is low (and easily
repaired) or high (requiring colostomy drainage). These patients will need
eventual workup for tethered spinal cord and urinary tract anomalies.
B. Post operative management:
•IV fluid replacement at maintenance levels with parenteral nutrition (see P. 136)
starting within 2d of operation. Intermittent fluid boluses may be required in the
first 48h to maintain adequate urine output and to treat hypotension and
hypoperfusion. Consider early use of low-dose dopamine (3-5 mcg/kg/min).
•If there has been extensive bowel manipulation, the baby may require baseline
fluid administration 1.5 times normal (i.e., 150 mL/kg/d) because of capillary
leak. Use Lactated Ringer’s Solution with 5% or 10% dextrose for at least the
first 24h after operation.
•Maintain Replogle tube to continuous suction and measure output. If drainage is
more than 10 mL/kg per 12h shift, replace volume loss with an equal volume of
0.45% NaCl.
•Replogle tube may be removed when drainage is minimal and non-bilious.
•After the baby has passed stool, start feedings with small volumes and advance
slowly over the next 48h to ensure that baby is not developing abdominal
distension secondary to postoperative ileus or to stricture at the anastomotic site.
 
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