|
Year |
2003 |
|---|---|
|
Question Number |
41. |
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Category |
Pediatric Orthopaedics |
Question
A tall, thin 13-year-old girl with idiopathic scoliosis undergoes instrumented posterior spinal fusion from T4 to L3. Postoperative recovery is uneventful, and a clear liquid diet is begun on the third day. The patient responds with vomiting and is unable to tolerate any oral intake; however, bowel sounds are normal. Nasogastric suction reveals large amounts of persistent bilious fluid drainage. The patient is afebrile, with a normal peripheral WBC count and normal serum amylase and lipase levels. What is the next most appropriate step in management?
1- Request psychological consultation and increase the patient’s sedative medications.
2- Aspirate the spinal wound and institute broad-spectrum antibiotic therapy.
3- Obtain a myelogram and revise the implants to lessen the correction.
4- Obtain an ultrasound of the kidneys and perform an exploratory laparotomy.
5- Obtain an upper gastrointestinal study and institute parenteral feedings.
Figures
Answer (click for answer)
Answer 5
Etiology:
" Cast Syndrome" or Superior Mesenteric Artery Syndrome is a rare complication after scoliosis correction (case w/ segmental derotational instrumentation w/ Luque instrumentation). The syndrome is due to compression of the duodenum due to a drastic decrease in the angle between the SMA and the abdominal aorta. SMA exits the aorto at L1. The angle between these vessels usually is 45°, with a range between 38° and 60°. The duodenum crosses at L3 , it passes between the aorta and SMA. In SMA syndrome, the angle is sharply decreased, ranging from 6° to 25° due to cases of spinal instrumentation the duodenum becomes trapped so called " nutcracker "effect. Rapid correction of kyposis as in the case study ( i.e. 75 degrees to 36 degrees has been implicated as a main feature).
Diagnosis:
Computed tomography is the best way to evaluate aortomesenteric distance, as well as to visualize
Upper GI series reveal dilated first and second portions of the duodenum, abrupt compression of the duodenal mucosal folds, to-and-fro movement of barium proximal to the obstruction
Classic sign " relief of the obstruction in the left lateral decubitus position. Also the Hayes maneuver, which is pressure applied below the umbilicus in a cephalad and dorsal direction This elevates the root of the small bowel mesentery, relieving the acute symptoms.
Therapy:
In orthopedic patients with an acute episode, there is a 100% rate of success with medical intervention only
1. total parenteral nutrition,
2. lying in the left lateral decubitus position).
The general agreement is to initiate medical treatment with intravenous fluids, frequent small meals of liquids, and the knee-chest position after eating. Metoclopramide therapy may be helpful.
Most chronic cases require surgery. Indications for surgery are (1) failure of conservative therapy; (2) a long history of indigestion, progressive weight loss, and pronounced dilatation of the duodenum with stasis; and (3) complicated peptic ulcer disease.
Reference: Pediatric Ortho: Transfeldt EE: complications of Treatment , Moe’s Testbook of Scoliosis and other spinal disorders, ed 3 1995, pp 451-481
Vitale et at. Superior mesenteric artery syndrome after segmental instrumentation: A biomechanical analysis. Am J Ortho 1999; 28: 461-467
Laplaza et al. Pancreatitis after surgery in adolescent idiopathic scoliosis; Incidence and risk factors. J Ped Ortho 2002, 22, 80-83.