64. Constipation Flashcards
what is constipation
It may be defined as defecation that is unsatisfactory because of infrequent stools (< 3 times weekly), difficult stool passage (with straining or discomfort), or seemingly incomplete defecation.
differentials for constipation
lifestyle related (low fibre, low activity, low fluid intake)
idiopathic/functional
Gastro:
IBS
IBD
Neoplastic:
- colorectal cancer
Metabolic and endocrine:
- hypothyroid
- hyperparathyroidism (hypercalcaemia)
History taking constipation
PC: constipation
HoPC and gastro system: gain understanding of their definition of constipation, how often (change from normal?), stool consistency (use bristol stool chart), any diarrhoea, vomiting, flatulence, blood, mucus, bloating, distension
Change in weight? Bone Stones, abdominal groans,
Renal system: change to water works
Red flags: blood, mucus, weight loss, weight gain
Any self-help measures or drug treatments tried?
DHx:
Opioids (including co-codamol and dihydrocodeine)
Anticholinergics (includes tricyclic antidepressants, oxybutynin)
Verapamil
Clozapine (can be life threatening, see guidance here)
Aluminium containing antacids
Iron and calcium containing preparations.
SHx: activity levels, diet, the severity and impact of symptoms on daily life and functioning.
Examination constipation
Abdo exam (tenderness, amsses, imapction)
DRE (any fissures, rectal masses, soft stool?hard stool?
Investigations constipation
Bedside
Abdominal exam
DRE
Bloods
FBC for anaemia
Serum U&Es
Calcium
Thyroxine (T4)
Glucose
Management chronic constipation
Counselling 1. advice on lifestyle measures
increasing dietary fibre
ensuring adequate fluid intake
ensuring adequate activity levels
Pharmacological
first-line laxative: bulk-forming laxative first-line, such as ispaghula
second-line: osmotic laxative, such as a macrogol (if hard)
Stimulant laxative eg senna (if soft)
if frail, consider softner first
when should you stop taking laxatives?
Advise the person to gradually reduce and stop laxatives once the person is producing soft, formed stool without straining at least three times per week.
Management opiod induced constipation
- Osmotic laxative eg lactulose PLUS stimulant laxative eg senna
Management acute constipation eg recent illness, immobility etc
- Senna (stimulant)
Management ibs constipation
- Docusate (softener)
what laxative should you avoid ibs
lactulose
what laxatives should you avoid opioid induced
Do not prescribe bulk-forming laxatives.
specialist management of refractory constipation
prucalopride (specialist prescribed)
consider if at least two laxatives from different classes have been tried at the highest tolerated recommended doses for at least 6 months, and failed to relieve symptoms, where invasive treatment (such as suppositories, enemas, rectal irrigation and/or manual disimpaction) is being considered.
complications of constipation
overflow diarrhoea
acute urinary retention
haemorrhoids
name a bulk forming laxative
ispaghula husk
name a softner laxative
docusate
name 2 stimulant laxative
senna
bisacondyl
name 2 osmotic laxative
macrogol
lactulose
when to not prescribe bulk forming
flatulence and bloating. Excessive doses or inadequate fluid intake may cause intestinal obstruction.
consideration macrogol
Macrogol laxatives can cause medications taken one hour before, during and one hour after to be flushed out of the gastrointestinal tract unabsorbed which includes contraceptive pills.
should you use two laxatives at the same time
NOT of same class
YES of different classes (synergistic
what to consider if diarrhoea on laxatives
impaction and overlfow
second line chronic constipation (after bulk forming)
add macrogol
define faecal loading
retention of faeces to the extent that spontaneous evacuation is unlikely
presentation faecal loading
PC: Hard, lumpy stools, which may be large and infrequent
or small and relatively frequent
Overflow faecal incontinence, or loose stool.
what does manual evacuation constipation - a finger having to be inserted into the vagina
rectocele
Management faecal loading
- Macrogol (osmotic)
- Add oral stimulant eg senna
- Enema or suppository
A suppository such as bisacodyl for soft stools; glycerol alone, or glycerol plus bisacodyl for hard stools.
A mini enema such as docusate (softener and weak stimulant) or sodium citrate (osmotic).
complications laxative abuse
low potassium, low sodium, dehydration
contraindications to stimulant laxatives
cramping, colitis, bowel obs etc
