8.3 (10.3) Constipation and diarrhea Flashcards
(36 cards)
List neurotransmitters involved in the regulation of:
- Intestinal motility - list 3 NTs
- Fluid handling - list 3 NTs
Peristalsis
◆ 5-hydroxytriptamine (5-HT)/ serotonin
◆ vasoactive intestinal protein (VIP)
◆ acetylcholine (Ach)
Fluid handling
◆ 5-hydroxytriptamine (5-HT)/ serotonin
◆ vasoactive intestinal protein (VIP)
◆ substance P
◆ neurokinin 1 and 2 receptors
List FOUR ways in which opioids cause constipation and TWO opioid receptors involved
bind mu- & kappa- receptors causing:
◆ dec peristalsis
◆ dec gut/rectal distension sensation
◆ dec intestinal secretions
◆ inc fluid reabsorption
◆ inc sphincter tone
A patient needs to be started on opioids, but is extremely sensitive to constipation. Which THREE opioids may have reduced constipating effect?
◆ methadone
◆ fentanyl
—
◆ buprenorphine
◆ alfentanil
—
◆ tramadol
◆ tapentadol
List FIVE functional factors that can lead to constipation
◆ Diet
- low fibre
- anorexia
- poor food/fluid intake
◆ Environment
- lack of privacy
- need for toileting assistance
- cultural issues
◆ Other
- inactivity
- age
- depression
- sedation
FS: think about non-pharm tx for constipation ( OT, PT, SWK, dietician)
List FIVE classes of medications that can cause constipation
◆ Opioids*
◆ Anticholinergic drugs*
◆ Antidepressants (serotonin)
◆ Antiemetics (serotonin)
◆ Iron*
◆ Antacids (Ca & Al compounds)*
◆ Diuretics (drying)*
◆ Anticonvulsants (sedating)
◆ Chemotherapy
◆ Vinca alkaloids (Vincristine)
Table 8.3.1
List THREE neurological disorders that can cause constipation
◆ autonomic dysfunction
◆ spinal/cerebral tumor
◆ spinal cord involvement
Table 8.3.1
List FIVE structural issues that can cause constipation
◆ Abdo/pelvic mass
◆ diverticular dz
◆ hernia
◆ colitis
◆ radiation fibrosis
◆ rectocele
◆ hemorrhoids
◆ Anal fissure/stenosis
◆ Ant mucosal prolapse
Table 8.3.1
FS: ABCD of BO (adhesion, bulge, cancer, diverticulum) + rectum
List FIVE metabolic problems that can cause constipation
◆ Dehydration*
◆ uremia*
◆ hypercalcemia*
◆ hypokalemia*
◆ Diabetes mellitus*
◆ hypothyroidism*
Table 8.3.1
An elderly patient has not had a bowel movement in 2 days. Today they have diarrhea and fecal incontinence. What is your provisional diagnosis? What investigation will you do? How will treat this patient?
fecal impaction with overflow incontinence
abdo exam with rectal exam
enema and disimpaction with sedation
then start oral stimulant and osmotic laxative (good evidence for daily PEG in fecal impaction)
Name 3 constipation assessment scales
◆ Bristol Stool Form Scale*
◆ Victoria Bowel Performance Scale (BPS)*
◆ Numerical rating of constipation on Pall assessment scales
◆ Stool Symptom Screener (SSS)*
◆ Bowel Function Index (BFI)
◆ Constipation Assessment Scale(CAS)
◆ Pt Assessment of Constipation-Symptoms (PAC-SYM)
List FIVE non-pharm mgmt for constipation
◆ Has evidence:
- abdominal massage
- position: forward posture + footstool
◆ Practical:
- Dietician - fluid/fibre intake balance
- PT - gentle movement (even bed to chair)
- OT - assisted walking, attention to privacy
You are designing a bowel protocol for hospice. List SIX medications you would include in your protocol
sennosides (stimulant laxative)
polyethylene glycol 3350 (macrogol) - renders water unabsorbable by the gut)
Laculose (osmotic laxative - increases secretion of water into gut lumen)
bisacodyl supp (stimulant supp)
glycerin supp (lubricating supp)
sodium phosphate enema
Mineral oil enema?
?sodium picosulfate oral (well tolerated stimulant laxative)
List THREE reasons bulk forming agents are not helping in cancer patients
◆ need to be taken with at least 200–300 mL of water
◆ consistency is unacceptable to many people who feel unwell
◆ effectiveness in severe constipation is doubtful
List THREE rectal interventions for management of constipation
◆ suppositories
◆ enemas
◆ manual evacuation/digital fragmentation of stool, w/ appropriate analgesia and sedation
What is the role of methylnaltrexone? How does it work?
◆ Methylnaltrexone is a peripherally acting mu-opioid receptor antagonists (PAMORAs).
- antagonizes only peripherally located opioid receptors while sparing centrally mediated analgesic effects of opioid pain medications.
◆ For OIC which has not responded to conventional laxative therapies
Relistor
What is the most common cause of diarrhea in the setting of palliative care? How would you manage this?
imbalance of laxative therapy
Temporarily stop laxatives for 24-48h and then reinstate at lower dose
List FIVE classes of medication that can cause diarrhea
◆ Antibiotics
◆ Laxatives
◆ Chemotherapy
◆ Immunotherapy
◆ Tyrosine kinase inhibitors
◆ NSAID, notably diclofenac
List FOUR “other” causes of diarrhea
◆ Diet
- excess fibre
- fruit
- alcohol
- spices
- sorbitol
◆ Other
- radiation colitis
- graft vs host dz
new
List THREE physiological (anatomical/structural) causes of diarrhea
◆ Cancer
- rectal/colonic
- pancreatic
- carcinoid
◆ Obstruction (overflow)
- malig bowel obstruction
- fecal impaction
◆ Malabsorption
- pancreatic carcinoma
- colectomy
- gastrectomy
- ileal resection
FS: IIEAT (expanding on ANATOMY - COM)
List SIX concurrent diseases that can cause diarrhea
◆ Diabetes mellitus
◆ Hyperthyroidism
◆ Chron’s Dz
◆ Ulcerative Colitis
◆ Diverticulitis
◆ Gastrointestinal infection
◆ Irritable bowel syndrome
What is the relationship between length of bowel removed in an ileal resection and subsequent risk of diarrhea? If diarrhea develops what is it caused by?
Ileal resection reduces the gut’s ability to reabsorb bile acids (97% are normally recirculated) -> producing chologenic diarrhoea (watery and explosive)
- <100 cm of terminal ileum is removed, fat malabsorption generally does not occur — as the liver can compensate for the increased biliary loss (by producing more bile acids)
- > 100 cm results in relative bile acid deficiency and hence fat malabsorption -> diarrhoea
-Also produces a disaccharidase deficiency proportional to the length of removed -> osmotic diarrhoea due to carbohydrate malabsorption
FS: bile acid increase peristalsis + gut fluid secretion –> diarrhea
A patient has a total colectomy and develops a high output ileostomy. What four diet replacements will the pt require?
-average of an extra litre of water per day
-7 g of extra salt to compensate
-Iron
-vitamin supplementation (A, D, E, K (fat soluble) and B and C)
List four red flag features in a patient with diarrhea
◆ fever
◆ neutropenia
◆ blood in stool
◆ dehydration
A patient has a stool anion gap of 25 (secretory diarrhea), what type of tumor may be responsible for this?
Anion gap = the difference between the stool osmolality and double the sum of the cation concentrations
> over 50 mmol/L = osmotic diarrhoea
<50 mmol/L = secretory diarrhoea, resulting from active secretion of fluid and electrolytes, as in the WDHA syndrome.
The WDHA syndrome (watery diarrhoea hypokalaemia achlorhydria) is associated with tumours of the pancreatic islet cells and of the sympathetic nervous system, including the adrenal glands, and can occur with bronchogenic carcinomas. VIP is thought to be the causative hormone
Ileal resection gives rise to a mixed picture, which will become purely secretory if the patient can be fasted
FS: VIPoma - type of neuroendocrine tumor