Constipation Flashcards
How to opioids lead to constipation? What other drugs can do this
Cause abnormal bowel peristalsis
Iron supplements and CCBs do the same
What is sigmoid volvulus
a condition in which the sigmoid colon wraps around itself and its own mesentery, causing a closed-loop obstruction
Rare but important intestinal obstruction
What non-GI structures may cause constipation due to bowel obstruction?
pelvic masses
(e.g. uterine fibroids,
ovarian tumour)
Causes of colonic stricture
radiotherapy, Crohn’s
disease, diverticular
disease
Why are you asking about bone pain in the context of constipation
Could suggest bone metastases, which would lead to hypercalcaemia that can cause constipation
What could Intermittent diarrhoea and constipation suggest
irritable
bowel syndrome (in younger patients), colorectal cancer (in patients >45
years, especially if the diarrhoea is mucoid), or diverticular disease (in patients
>60 years, especially if they have had episodes of left iliac fossa pain).
What could blood on faeces, per rectum or when wiping indicate
May suggest haemorrhoids,
anal fi ssure, diverticular disease, or colorectal cancer
Most common aetiology of constipation & management
A combination of lack of fibre in the diet, dehydration, and a degree of immobility.
- Drink lots
- Eat fibre-rich cereal/wholemeal bread
- Osmotic laxatives (only accutely as they cause dehydration)
- Stool softeners (liquid parrafin and arachis oil enemas)
- Peristalsis stimulants
- Phosphate enemas (last resort)
How does fibre help constipation
fi bre helps constipation by providing bulk (which activates stretch receptors in the bowel and triggers peristalsis) and by retaining water (which makes faeces softer).
What can be given if patient cannot achieve significant bulk by diet alone
methylcellulose tablets, ispaghula husk
Examples of peristalsis stimulatnts
glycerol suppositories, bisacodyl, or senna
What is a +phalens sign
prolonged wrist hyperfl exion reproduces the hand symptoms of numbing, tingling feeling
Suggests carpal tunnel syndrome
Most common cause of hypothyroidism in 22 year old female
Th e most likely cause for hypothyroidism in a woman of this age is chronic autoimmune thyroiditis, also known as Hashimoto’s hypothyroidism.
How do you confirm hypothyroidism, how do you show something is specifically hashimotos
Hypothyroidism is easily confi rmed by a blood test revealing a high TSH level, which is due to the lack of suffi cient thyroxine to negatively feed back on its production. If this is Hashimoto’s hypothyroidism, one will also find high antithyroid peroxidase antibodies.
Hypercalcaemia symptoms are commonly described as
‘moans, groans, bones, and stones’ referring to the depression, aches and pains, and renal stones often found in this condition. Polidipsia and polyuria are also common, with the classic (but rarely seen) hypercalcaemia patient waking up at night to down a glass or two of water
Causes of hypercalcaemia
Bone mets, myeloma, primary/tertiary hyperparathyroidism, vit D overdose
What happens to bone cells in myeloma and thus what happens to ALP
In myeloma, osteoclasts are activated and osteoblasts are inhibited. As ALP comes from osteoblasts, it remains normal.
Calcium is high and PTH is normal, could this be hyperparathyroidism?
Yes, Note that PTH levels are often in the ‘normal range’ but that this is actually abnormal as they should be low in the presence of high calcium (remember that PTH release is normally inhibited by high calcium levels). •
Causes of primary hyperparathyroidism
Th is is usually caused by a solitary, benign parathyroid adenoma, although parathyroid hyperplasia, parathyroid carcinoma, or PTH-secreting ectopic tumours also occur
Which drug has been specifically deveoped to deal with opioid induced constipation
Methylnaltrexone
Best way to confirm bowel obstruction?
Th e best way to confi rm bowel obstruction is a plain abdominal radiograph. Small bowel loops with a diameter >3 cm, or large bowel loops with a diameter >6 cm, indicate bowel obstruction.
Coffee-bean sign is what? What does it indicate
an enormous, dilated loop of bowel, shaped like a coff ee bean and extending from the pelvis up to the diaphragm), caused by the sigmoid portion of the bowel twisting on itself
Indicates sigmoid volvulus
How do you remove the obstruction in:
i. sigmoid voluvulus
ii. colorectal cancer
iii. Diverticulitis
i. In sigmoid volvulus, this is done using a sigmoidoscope with a long, soft flatus tube to untwist the bowel, or surgery if this is unsuccessful or the patient is peritonitic.
ii. In colorectal cancer, a metallic stent can be used to relieve the obstruction until the tumour is removed surgically
iii. can be used to relieve the obstruction until the tumour is removed surgically. In diverticulitis, reduction of the infl ammation with bowel rest and antibiotics may be enough to reduce the obstruction, although surgical resection is occasionally necessary.
