A 9-month-old girl is presented with PR bleed, vomiting, mass & colicky pain in Rt lumbar region with masked liver dullness. She is in shock like condition. Management should includes – a) Barium enema b)  Saline reduction c)  Give O2 d)  Nasogastric tube d)  IV fluid
PR bleed, vomiting, mass in right lumbar region, colicky pain and masked liver dullness in a 9-month infant suggest the diagnosis of intussusception.
Patient is also having shock, so she requires treatment of shock and intussusception.

Diagnosis of intussusception 

The clinical history and physical findings are usually sufficiently typical for diagnosis. Plain abdominal radiographs may show a density in the area of the intussusception. A barium enema shows a filling defect or cupping in the head of barium where its advance is obstructed by the intussusceptum. A central linear column of barium may be visible in the compressed lumen of the intussusceptum, and a thin rim of barium may be seen traped around the invaginating intestine in the folds of mucosa within the intussuscipiens (coiled-spring sign), especially after evacuation.
Retrogression of the intussusceptum under the pressure of the enema and gaseous distention of the small intestine from obstruction are also useful radiographic signs.
Ileoileal intussusuception is usually not demonstrable by barium enema but is suspected because of gaseous disten­tion of the intestine above the lesion. The use of "air" enemas in the diagnosis and treatment of intussusception has supplanted hydrostatic reduction. Reflux of air into the terminal ileum and the disappearance of the mass at the ileocecal valve document successful reduction. Air reduction is associated with fewer complications and lower radia­tion exposure than traditional hydrostatic techniques.
Ultrasonography is a sensitive diagnostic tool in the diagnosis of intussusception.

Treatment of Intussusception 

The child should be first stabilized. A tube should be passed into the stomach through nose (nasogastric tube). An intravenous line should be placed and fluids should be given to prevent dehydration.
Reduction of an acute intussusception is an emergency procedure and performed immediately after diagnosis in preparation for possible surgery. The reduction can be achieved by installation of barium, saline or air.

"In patients with prolonged intussusception with signs of shock, peritoneal irritation, intestinal perforation or pneumatosis intestinal, reduction (with barium, saline or air) should not be attempted".

In the above cases and in cases where reduction by barium/saline/air fails, surgery is required, i.e., manual operative reduction.
If the manual operative reduction is not possible or the bowel is not viable, resection of the intussusception is necessary, with an end to end anastomosis.
Treatment of shock (e.g. O2 IV fluid etc) should be given first if it is present.

About option a & b

As the patient is in shock, reduction by air or barium is contraindicated. However, a barium enema can be used as a diagnostic modality.
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