7- Bowel Dysfunction Flashcards
Draw & explain bowel innervation. 🔑🔑 (OSCE)
SYMPATHETIC NERVOUS SYSTEM
Upper 1/3 Superior mesentric ganglion T4-T12 (Celiac ganglion → Autonomic Dysreflexia)
Lower 2/3 Inferior mesentric ganglion and hypogastric n. T10-L2 → Internal Anal Sphincter
Function: Inhibits colonic contractions → storage
PARASYMPATHETIC NERVOUS SYSTEM
Upper 1/3 Vagus nerve (CNX) which innervates proximal to mid-transverse colon
Lower 2/3 Pelvic n. (S2–S4) → Internal Anal Sphincter
Function: Enhances colonic motility → defecation
INTERNAL ANAL SPHINCTER
Sympathetic tone causes contraction of the internal anal sphincter
Parasympathetic tone causes relaxation of sphincter tone.
EXTERNAL ANAL SPHINCTER
Pudendal nerve (S2–S4)
Function: voluntary control → maintain continence.
Sequence of event in normal defecation What are the 3 muscles important for maintaining fecal continence? 🔑🔑 MOCK 2021
(A) Defecation is prevented by increased tone of
- Internal anal sphincter (IAS)
- External anal sphincter (EAS)
- Puborectalis
(B & C) Defecation is initiated by
- Relaxing puborectalis muscle and EAS
- Contraction of levator ani, abdominals, and diaphragm
- Rectum contraction to complete evacuation
Spinal Cord Medicine Principles and Practice - 2nd Edition (2010)
Braddom 4th Edition Chapter 21 Bowel pg454 Figure 21-4
Compare internal and external anal sphincter. 🔑🔑
Internal Anal Sphincter
- Smooth Muscles
- Sympathetic (contraction)
- Parasympathetic (relaxation)
External Anal Sphincter
- Circular band of striated skeletal muscle (Part of the pelvic floor)
- Somatic innervation from the pudendal nerve (S2–S4) for voluntary continence
Cuccurollo 4th Edition Chapter 7 SCI pg582
Auerbach’s (Myenteric) plexus is located in? why it’s important?
Auerbach’s (Myenteric) plexus
- Part of autonomic nerves system of the bowl
Location
- Muscularis propria between circular and longitudinal muscle layers
Function
- Control gut secretions
- Control blood flow
- Muscular activity giving the colon the ability to produce peristalsis.
💡 After SCI, autonomic (sympathetic/ parasympathetic) and somatic neural input is disrupted, but the enteric system remains intact
List two types of dietary fiber, and their effects on the GI system.
Insoluble fiber
Promotes the movement and bulk of stool
Beneficial to those who struggle with constipation or irregular stools.
Soluble fiber
Dissolves in water to form a gel-like material.
It can help lower blood cholesterol and glucose levels.
List 6 symptoms of fecal impaction in the elderly. 🔑🔑
GENERAL
- Anorexia
- Confusion
- Agitation
- Worsening psychosis
REAGONAL
- Nausea & Vomiting
- Constipation
- Abdominal pain
- Fecal incontinence (Paradoxical diarrhea)
- Urinary frequency
- Urinary overflow incontinence
https://www.researchgate.net/figure/Symptoms-Associated-with-Fecal-Impaction_tbl1_235756213
List 4 major reflexes that influence bowel function. 🔑
1- Gastrocolic reflex
- Nerve: vagus nerve
- Contraction of the colon occurring with gastric distention
- Patients to be instructed to perform their bowel programs 20 to 30 minutes after a meal.
- Increased colonic activity occurs in the first 30 to 60 minutes after a meal (usually within 15 minutes)
2- Colo-colonic reflex
- Inhibition of contraction in one portion of the intestinal tract by distention of another
- Mediated by prevertebral ganglia, not the spinal cord, so they likely would be unaffected by SCI
3- Rectocolic defication reflex
- Nerve: pelvic nerve S2-4 (parasympathetic)
- Occurs when rectal contents stretch the bowel wall reflexively
- Relaxing the internal anal sphincter and leading to left colonic contraction
- Digital stimulation is accomplished by gently inserting a gloved, lubricated finger into the rectum, and slowly rotating the finger in a clockwise circular motion until relaxation of the bowel wall is felt or stool/flatus passes (approximately 1 minute).
- Suppositories and digital stimulation cause the bowel wall to stretch and take advantage of this reflex.
4- Rectoanal inhibitory reflex
- Transient relaxation of the IAS stimulated by a rise in rectal pressure
- Occurs during sleep and throughout the day
5- Guarding reflex
- Preserve continence while sensory receptors of the anorectal junction appraise the contents.
Delisa 5th Edition Chapter 51 Neurogenic Bowel & Bladder pg1375-1377
Cuccurollo 4th Edition Chapter 7 SCI pg584
Name 5 changes in bowel function / GI complications that occur after SCI? 🔑
TWO MAIN DYSFUNCTION
- Fecal Incontinence: Diarrhea, Electrolyte Imbalance, Dehydration, Leak, Accidents
- Fecal Impaction: Constipation, Abdominal Pain, Bloating, and Early Satiety, GERD
ORGANS
- ESOPHAGUS: Dysphagia, GERD
- STOMACH: Gastroparesis, Bloating
- INTESTINE: Superior mesenteric artery syndrome, Increased transit time, Decreased bowel/colonic motility, Constipation, Diverticulosis
- RECTUM: Hemorrhoids 74%, Rectal prolapse
- SPHINCTER: Flaccid sphincter (leaking, and accidents), Spastic sphincter (fecal impaction), Fissures
- RISK of Autonomic dysreflexia
SCIRE, bowel management; Braddom pg 627.
Spinal Cord Medicine Principles and Practice Table 31.1
Cuccurullo 4th Edition Chapter 7 SCI pg 585.
List 4 Medications that cause worsening of neurogenic bowel List 4 Predisposing factors for constipation 🔑
Medications
- Antidepressants
- Anti-spasticity medications
- Anticholenergics
- Pain medications
Factors
- Decreased dietary fiber intake
- Dehydration
- Decreased mobility/activity
- Anticholerengic side effects
- Degenerative disease (Dementia, Parkinson)
- Depression
UMN vs LMN Bowel. Lesion - Muscles & Sphincter - Reflexes - Presentation - Stool - Tx 🔑🔑
Key difference is if its UMN or LMN lesion 3 marks.
In SCI, We will loss sympathetic and parasympathetic input to the colon:
- Decreased fecal movement → Fecal impaction and constipation in any injury
- Colonic peristalsis still occurs due to the activity of the intrinsic myenteric plexus
Key difference is if its UMN or LMN lesion
- Reflex defecation
- Anal sphincter tone
- Anal wink & Bulbo-anal Reflex
https://community.scireproject.com/topic/bowel/#spastic-and-flaccid-bowel
Spinal Cord Medicine Principles and Practice - 2nd Edition (2010)
Neurogenic Bowel Guidelines Sept, 2012
A 35 year old woman presents to clinic 18 months after flaccid paraplegia that resulted from an L1 burst fracture. She is wearing diapers as a bowel program. The change in bowel care technique that would most likely lead to an improvement in fecal continence would be
Schedule bowel care after breakfast and dinner daily with manual evacuation
The bowel care technique for the first several days following a spinal cord injury is most effectively accomplished with
Manual evacuation of feces as patient will be in spinal shock state.
List 3 physical exam maneuvers to assess neurological control of the rectum 🔑🔑
1. Anal wink (S2-4)
Contraction of the external anal sphincter upon stimulating skin around the anus
2. Bulbocavernosus Reflex (S2-4)
Compressing the glans penis in males or by applying pressure to the clitoris in females and observing contraction of the anal sphincter.
3 Anal tone and voluntary anal contraction (VAC)
Innervated via pudendal nerve
4. Sensation (Pin prick in S4-5)
5. Deep anal pressure (DAP)
Name 3 cutaneous reflexes that can be assessed in UMN bowel D/Os. 🔑
- Bulbocavernosus reflex (S2-4).
- Anal wink/anocutaneous reflex (S2-4).
- Plantar response (test of UMN).
- Cremaster reflex (T12-L1-2; genitofemoral nerve).
- Abdominal reflex (Upper: T8-T10; Lower: T10-T12).
Ref: Neurology resident guide.
List 3 clinical features of classic superior mesenteric artery (SMA) syndrome List 3 predisposing factors for SMA syndrome 🔑
Symptoms
- Bloating
- Abdominal pain
- Postprandial nausea and vomiting
Predisposing factors include
- Rapid weight loss (decrease in protective fatty layer)
- Prolonged supine position. Most common in tetraplegia.
- Spinal orthosis
Cuccurolo 4th Edition Chapter 7 SCI pg587
Name 5 non-surgical, non-pharmacological interventions that may improve bowel care. 🔑🔑 List 3 mechanical methods, hands-on bowel techniques 🔑🔑 (MOCK 2022)
- Anal irrigation system
- Abdominal massage with clockwise starting from lower torso in a to increase movement within the colon
- Timing of food and drink to stimulate gastrocolic reflex
- Digital rectal stimulation to stimulate anorectal reflex (for UMN) for 20 seconds and repeated every 5 to 10 minutes
- Manual removal of stool (both UMN & LMN)
- Dietary Fibre around 25-30g per day
- Fluids 2-3 Liter per day
https://community.scireproject.com/topic/bowel/#hands-on-bowel-technique
Others
- Maintain physical activity levels, limit immobility
- Minimize medications that decrease bowel motility e.g. narcotics, TCAs, anticholinergics
- Electrical stimulation of abdominal wall muscles
List 4 Assistive devices for bowel care 🔑🔑
- Commodes, raised or padded toilet seat, or automated toilet seat
- Suppository inserter or digital stimulator
- Mirrors
- Anal plugs
- Footstools
- Bowel irrigation systems
https://community.scireproject.com/topic/bowel/#other-treatments-and-techniques
S/E of bowel medications? “Think too much stool” 🔑
- Abdominal Cramps
- Diarrhea
- Electrolyte Imbalance
- Dehydration
Name 5 surgical interventions directed to improve bowel care/functioning
- Colostomy
- Ileostomy
- ACE procedure (aka MACE procedure): Malone anterograde continence enema
- Muscle graft for puborectalis sling
- Sphincter myotomy for dyssynergia
- Sacral anterior root stimulation
What is a Malone procedure and how does it work?
Malone antegrade continence enema
It is a surgical procedure done by connecting the appendix to the abdominal wall with one way valve mechanism that facilitates fecal evacuation using enemas and avoids leakage of stool through it.
What causes ―cathartic bowel syndrome?
Cathartic bowel syndrome
Anatomic and physiologic change in the colon that occurs with chronic use of stimulant laxatives (> 3 times per week for at least 1 year) resulting impaired fecal propulsion
Signs and symptoms
- Bloating, a feeling of fullness
- Abdominal pain
- Incomplete fecal evacuation
- Laxative dependency to defecate.
What are Rx options for fecal incontinence? 🔑🔑 (Ward Call)
-
Rule out causes of incontinence
- Stool impaction
- C. Difficile infection
- Medications side effect
-
Behaviour management
- Timed bowel movements
- Pelvic floor exercises (LMN bowel)
- Increase fruit and vegetables
- Limiting caffeinated beverages
-
Assistive Devices
- Anal plugs
-
Medications
- Antiperistaltic drugs (Imodium) to absorb more liquid
- Bulking agent - psyllium husk
- Pepto bismol
- Vancomycin (C. Difficile infection)
-
Manage Complications
- Fluid and electrolyte replacement
- Skin care and hygiene to prevent pressure injury and infection
https://scireproject.com/wp-content/uploads/bowel_management-1.pdf
The goals of the bowel program should include 🔑🔑 (OSCE)
- Stool evacuation at regular, predictable time
- Limit incontinence and accidents
- Completing emptying within <60 minutes
- Stools that are soft, formed, and bulky.
- Minimize complications (Diarrhea, Constipation, Fecal impaction, Hemorrhoids (piles)
Why is bowel care after SCI important? Complications of poor bowel care 🔑🔑
💡 Easy to think about passing too much vs not passing at all
- Skin breakdown
- Pressure wounds
- Autonomic dysreflexia.
- Severe constipation, fecal impaction
- Unexpected accidents
- Interfere with important activities like work, socializing and sexual intimacy
https://scireproject.com/evidence/rehabilitation-evidence/bowel-dysfunction-and-management/
Prescribe complete bowel management for any patient with bowel dysfunction 🔑🔑 (OSCE)
-
BEHAVIORAL / LIFESTYLE
- 2-3L fluids with five portions of fruit and vegetables and significant levels of whole grain foods, such as wholemeal bread or unrefined cereals.
- Hyperreflexic bowel should aim for soft-formed stool consistency (Bristol Scale 4)
- Areflexic bowel function should aim for firmer stools (Bristol Scale 2-3) to avoid fecal incontinence
- Abdominal massage, clockwise direction
- Take some food and/or drink 15 - 30 minutes prior to commencing other bowel management activities (benefit from gastrocolic reflex)
-
DIGITAL STIMULATION (UMN BOWEL)
- Rotating the finger in a circular movement, maintaining contact with rectal mucosa
- Stimulus is continued until relaxation of the external sphincter is felt, flatus or stool passed
- Required for 15-30 seconds and rarely 1 minutes
- Stimulation may be repeated every 5–10 minutes approximately until evacuation is complete
-
DIGITAL EVACUATION (UMN & LMN BOWEL)
- Recommended in the early acute phase after SCI to remove stool from the areflexic rectum to prevent over-distension
- Can be used by both areflexic bowel dysfunction (removal of stool only) and reflexic bowel dysfunction (removal of stool prior to placing suppositories or to complete evacuation where reflex activity alone is insufficient to empty the bowel)
-
ORAL MEDICATIONS
- Softeners (e.g. dioctyl), bulkers (e.g. ispaghula husk) and osmotics (e.g. polyethylene glycol, lactulose): taken regularly to maintain a predictable consistency
- Stimulants (e.g. senna, bisacodyl): taken only prior to planned evacuation of stool otherwise they may increase risk of faecal incontinence in individuals with impaired faecal continence
-
RECTRAL MEDICATIONS
- Glycerin suppositories: stimulus and lubricant, response in around 20 minutes
- Bisacodyl suppositories: stimulant laxative
- Fleetenemas (microenemas)
- Large volume phosphate enemas are not used routinely: risk for autonmic dysreflexia
Bowel Care UMN vs LMN 🔑🔑 (OSCE)
Goal:
UMN: Bristol scale 4
LMN: Bristol scale 3
Steps
- Stimulant laxative 8-12 hours before planned bowel care if necessary
- Have meal or warm water 30-60 minutes before bowel care
- In case of UMN, patient can benefit from rectal stimulation (digital - enema - medications)
- In case of LMN, patient can benefit from Valsalva and use squatty potty / foot stand
- Start abdominal massage
- Digital rectal evacuation
- Check every 5-10 by single digit to ensure rectum is empty, if not repeat step 3-5
- Clean up and dry the anal area
