GP info
Nutritional deficiencies - What to look for post bariatric surgery
Protein malnutrition / protein energy malnutrition
Protein malnutrition can occur for a number of reasons including poor dietary choice,
anastomotic stricture or protein malabsorption (short gut). It may present several
years following surgery. Protein energy malnutrition is accompanied by oedema. In
all cases of suspected protein malnutrition the patient must be fast tracked back the
Bariatric team
Anaemia
Iron deficiency anaemia
Whilst iron deficiency anaemia is relatively common following the gastric bypass, it
must not be assumed that this is the only cause. Other causes should also be
considered and investigated if appropriate.
If additional oral iron does not correct the iron deficiency anaemia, parenteral iron or
blood transfusions may be necessary. Ensure that the patient maintains levels with
oral iron supplements. These should be taken with meals or drinks containing
vitamin C to aid absorption and at a different time to calcium supplements.
If the anaemia is not due to iron deficiency or blood loss, other nutritional causes
should be considered. These include folate, vitamin B12, zinc, copper and selenium.
Folate and vitamin B12
Low folate levels may be an indication of noncompliance with multivitamin and
mineral supplements. However, it could also be an indication of severe
malabsorption especially if there are other nutritional deficiencies. Megaloblastic
anaemia is caused by folate deficiency or vitamin B12 deficiency. Vitamin B12
deficiency, if untreated, results in irreversible peripheral neuropathy. Therefore it is
essential that vitamin B12 deficiency is considered before recommending additional
folic acid. Those patients who are vitamin B12 deficient should have levels corrected
with intramuscular injections of vitamin B12. Once corrected, three monthly injections
of 1mg vitamin B12 will maintain levels.
Calcium, vitamin D and parathyroid hormone levels
Vitamin D deficiency may result in secondary hyperparathyroidism to maintain
calcium levels.
Zinc, copper and selenium
Unexplained anaemia, poor wound healing, hair loss, neutropaenia, peripheral
neuropathy or cardiomyopathy may be symptoms of zinc, copper or selenium
deficiency and so levels should be checked if there are any concerns. Zinc and
copper share a common pathway so supplementation with zinc can induce copper
deficiency and vice versa. Information about any additional over the counter
supplements the patient may be taking is essential. If additional zinc
supplementation is required, a ratio of 1 mg copper for every 8 to 15 mg zinc must
be maintained.
When to request specialist biochemical / nutritional advice or to refer your
patient:
Diagnosis and management of micronutrient deficiency syndrome can be complex
and so when in doubt it is recommended that specialist advice is sought. The
following are examples of situations where this is appropriate.
- Newly identified biochemical deficiency, where there is differential diagnosis
(there can be causes other than previous bariatric surgery) or its appropriate
investigation and treatment are uncertain.
- Unexplained symptoms that may be indicative of underlying micronutrient /
trace element deficiencies.
- Women who have undergone previous gastric bypass or sleeve gastrectomy
and who are planning to become pregnant or who are pregnant.
Post operative multivitamin
- These are best started upon discharge. A chewable form is recommended for
the initial 2 weeks. Celebrate Bariatric chewable Multivitamin can be
ordered through amsnutrition.co.nz.
Centrium Advance 50+ or Centrium
Woman's multi (x2 per day) once on pureed diet (2-3 weeks post procedure)
- Oral Vitamin D 50000IU monthly
- 6-12 monthly Vit B12 injections
- Possible oral solutions available through amsnutrition.co.nz
- Calcium carbonate is recommended 500mg daily
