Question

Patient C.D. is a 55-year-old female who had a mastectomy done two days ago. Her medical history is significant for breast cancer, hypertension, and anemia. During change of shift report, you hear from the outgoing night shift nurse that yesterday, on the first day after surgery, the patient was experiencing persistent nausea. This was considered to be an unfortunate side effect of the anesthesia used during surgery. The patient ate only clear liquids yesterday morning but then her nausea improved slightly after receiving an anti-nausea medication. The patient ate solid food yesterday afternoon and evening. Today the patient reports to you that she is having abdominal discomfort and more nausea. She is not interested in eating her breakfast. When you ask, she says she is not passing flatus. You suspect the patient has a postoperative ileus.

Fortunately patient C.D. begins to feel better after a day of bowel rest. Her bowl sounds and nausea improve, and she passes flatus. She begins to tolerate a clear liquid diet, and is slowly advanced to solid food again.

1. Had she had a more severe ileus with persistent signs of disrupted bowel motility, what could be placed to help remove gastric contents and relieve abdominal pressure?

2. What would be an important nursing consideration for this patient to help monitor for fluid balance?

Answer 1

Pathogenesis of postoperative ileus:

1. Reduced basal electric activity in the stomach
2. Reduced parasympathetic activity
3. Increased sympathetic activity
4. Increased inflammation in the body wall due to surgical manipulation of the gut. There is an increase in the levels of cyclooxygenase -2 and neutrophil infiltration.
5. This leads to reduces jejunal motility
6. Atropine, anesthetic agents like halothane, enflurane reduce gastric empty.
7. Opioids reduce gastric empty, increase tone in the antrum and first portion of the duodenum.

Answer1:

A nasogastric tube can be inserted and gastric aspiration can be done through the nasogastric tube.

This will reduce the gastric content and abdominal distension

Criticism of use of nasogastric tube aspiration:

1. it doesn't alter the course of postoperative paralytic ileus
2. It doesn't increase gastric motility.
3. There is a risk of pulmonary aspiration, fever, and lung collapse.
4. Randomized trials have demonstrated no benefit of use of nasogastric tube in treatment of postoperative paralytic ileus

Answer2:

The fluid balance should be maintained in these patients because:

1. The patient is unable to eat on his own - this can lead to dehydration.
2. Naso-gastric suction can cause metabolic alkalosis and hypokalemia
   • the gastric secretions are rich in hydrochloride (HCL)
   • This acid is neutralized in the small bowel by bicarbonates.
   • Naso-gastric tube suction leads to the removal of HCL, as a result, bicarb is not secreted into the small intestine.
   • In other words, there is a net gain of bicarb in the systemic circulation.
   • This leads to metabolic alkalosis. This is chloride responsive metabolic alkalosis ( urine chloride < 20)
   • Metabolic alkalosis and dehydration ( via aldosterone secretion) lead to hypokalemia.
   • Hypokalemia can result in cardiac arthymia.
3. This can be corrected by the infusion of isotonic saline with potassium correction.
4. The crystalloid of choice is 0.9% saline. care should be taken to prevent hypernatremia.
5. The patient should receive 50 - 100 mmol/day of sodium, 40 - 40 mmol/day of potassium and 1 - 1.5 liters of water ( additional 500 ml may be added to compensate from insensible fluid losses through nasogastric suction)