A newborn suffering from perforated necrotizing enterocolitis is having the very poor general condition. He is currently stabilized on a ventilator. Which of the following should be done in the management of this patient –
Necrotizing enterocolitis (NEC) is the most common life-threatening emergency of the GIT in the newborn period.

Management of necrotizing enterocolitis

Medical treatment of NEC include
Cessation of feeding
Nasogastric decompression
Administration of i.v. fluids
Systemic antibiotic against both gram +ve as well as gram -ye bacteria (after taking samples for blood culture).
Ventilation should be assisted if distention is contributing to hypoxia.
Early surgery consultation

Surgical interventions in NEC

Evidence of perforation is an indication for laparotomy and resection of necrotic bowel.
Failure to respond to medical management, a single fixed bowel loop, erythema of the abdominal wall and a palpable mass are additional indications of exploratory laparotomy, resection of necrotic bowel and external ostomy diversion.
Peritoneal drainage may be helpful for patients with peritonitis who are too unstable to withstand surgery. It is more successful in patients with isolated intestinal perforation. In many patients, no further surgical procedure is required.
Peritoneal drainage is performed under local anaesthesia. Alpenrose drain is placed in the right lower quadrant and permitted to drain peritoneal contents and decompress the abdomen. This procedure is employed predominantly in infants less than 1000g who have severe SIRS and are viewed as too unstable to be transported or to undergo laparotomy. In experienced hands, one-third of the patients require only drain placement.
A primary anastomosis at the time of initial surgery is indicated in patients with limited localized disease who have no distal bowel involvement and in patients who have demonstrated a walled-off perforation who are no longer manifesting the SIRS.

From this discussion, we choose the answer to be peritoneal drainage because:

Patients are on a ventilator (too unstable).
Surgery for NEC is resection and creation of an ileostomy, which is not given in the options.
Primary anastomosis is done only in stable patients with walled-off perforation.
Conservative treatment
Resection and anastomosis
Stabilization with membrane oxygenator and defer surgery
Peritoneal drainage by putting drains in the flanks