CASE LEARNING OBJECTIVES
List the appropriate indications for the use of parenteral nutrition (PN)
List the elements of a nutrition assessment and factors considered in assessing a patient's nutritional status and nutritional requirements
Develop a plan to design, initiate, and adjust a PN formulation using patient-specific factors
Describe the etiology and risk factors for the refeeding syndrome
Design a plan to monitor and correct fluid, electrolyte, vitamin, and trace-element abnormalities in patients receiving PN
Design a plan to monitor and assess the efficacy and safety of PN therapy
"I've had an upset stomach and pain which has been getting worse for about 10 days, and I started vomiting about 3 days ago. I can't keep any food or liquids down."
History of Present Illness
Alex Rocker is a 46-year-old man with a history of morbid obesity s/p Roux-en-Y gastric bypass surgery in February 2010 for morbid obesity, who was admitted to the hospital 5 days ago on November 2, 2012, with abdominal pain, nausea, vomiting, and inability to tolerate oral intake. His postoperative course was complicated by anastomotic leak, peritonitis, sepsis, and high-output enterocutaneous (EC) fistula. He was initially placed nothing per os (NPO) with home PN and wound care for 6 months, and afterward underwent surgery for EC fistula takedown and small bowel resection with primary anastomosis. The patient has also had recurrent partial and total small bowel obstructions due to adhesions and had 2 other surgeries (exploratory laparotomies) for lysis of adhesions (in May 2011 and September 2012). Since his initial gastric bypass surgery, the patient lost approximately 100 lb (∼46 kg) of his original pregastric bypass weight of 295 lb (134 kg). For the past 10 days before presentation to the emergency department, he has had worsening nausea and abdominal pain that initially developed after eating a meal and appeared to get worse after eating. The abdominal pain gradually worsened, was associated with vomiting for the past 3 days, and he could not keep any food or liquids down. He described his symptoms as similar to the last time he had a bowel obstruction, but they now seem worse.
The patient was subsequently admitted to the GI surgery service for further management. Initially, he was managed conservatively by placing a NG tube for gastric fluid suctioning and bowel decompression, was placed NPO, and started on IV fluids for hydration. After 2 days of conservative management, the patient did not show any signs of improvement of his GI symptoms. A CT scan with oral contrast was done and demonstrated a complete small bowel obstruction. The surgical team decided on observing the patient and continuing conservative management for about a week until the patient's symptoms would resolve or otherwise would necessitate surgical intervention. Because the patient has had poor nutritional intake for about 12 days since ...