Constipation
This page is for adult patients; for pediatric patients see constipation (peds).
Background
- Acute constipation is intestinal obstruction until proven otherwise
Red flags
- Weight loss
- Rectal bleeding/melena
- Nausea/vomiting
- Fever
- Rectal pain
- Change in stool caliber
Clinical Features
- Decreased frequency of bowel movements
- Hard, dry, and/or difficult to pass stool
Differential Diagnosis
Constipation
- Behavioral-related
- Lack of exercise
- Diet-related
- Fecal impaction
- Ileus from surgical abdomen
- Bowel obstruction
- Small bowel obstruction
- Large bowel obstruction
- Malignant bowel obstruction
- Specific causes: tumor, stricture, hernia, adhesion, volvulus
- Painful anorectal disorders (e.g. anal fissure, hemorrhoids)
- Medical causes
- Hypothyroidism
- Electrolytes
- Hypokalemia
- Medication-related
- Opiods, antipsychotics, anticholinergics, antacid, antihistamines
- Constipation (peds)
Anorectal Disorders
- Anal fissure
- Anal fistula
- Anal malignancy
- Anal tags
- Anorectal abscess
- Colorectal malignancy
- Condyloma acuminata
- Constipation
- Crohn's disease
- Cryptitis
- GC/Chlamydia
- Hemorrhoids
- Pedunculated polyp
- Pilonidal cyst
- Proctitis
- Pruritus ani
- Rectal foreign body
- Rectal prolapse
- Syphilitic fissure
Abdominal distention
- Obesity
- Intestinal obstruction
- Pregnancy
- Ascites
- Cirrhosis
- Malignancy
- Heart failure
- Tuberculosis
- Spontaneous bacterial peritonitis
- Peritoneal dialysis-associated peritonitis
- Distended bladder / Acute urinary retention
- Constipation / fecal impaction
- Large tumor(s) (e.g. ovarian, lymphoma)
- Organomegaly
Evaluation
Work up
- Digital rectal exam
- Abdominal panel
- CBC
- Chemistry (hypokalemia or hypercalcemia)
- LFTs + lipase
- Consider coagulation studies (PT, PTT, INR), as a marker of liver function
- Consider TSH if concern for hypothyroid related constipation
- Consider lactate if concern for stercoral colitis
- CT if abdominal tenderness, elderly, or severe presentation
- Constipation should not cause abdominal tenderness on exam
- CT may show stool burden in colon/rectum
Diagnosis
- Diagnosis is frequently clinical
- In patients with concerning symptoms/risk factors, CT can confirm diagnosis and rule out more emergent conditions
Management
- Adequate fluid (1.5L per day)
- Fiber (10gm per day)
- Bran: 1 cup daily
- Psyllium (Metamucil): 1-2 teaspoon TID
- Exercise
Medication options
- Emollient
- Docusate (Colace): 100mg QD-BID (facilitates mixture of stool fat and water)
- Mineral oil (long term use causes malabsorption)
- Stimulants
- Saline laxative
- Milk of mangesia: 15-30 mL QD-BID
- Magnesium citrate: 100-240 mL QD-BID
- Hyperosmolar agents
- Enemas
- Soap suds, saline, tap water enema (rectal distention, causing evacuation)[1]
- May add 50-100 mg of docusate liquid to saline or water enema
- Fleet Phospho-soda: 118 ml single enema dose, with maximum of x2 doses at least 1 hr apart
- No more than 2 doses in a 24 hr period may be administered without serum phos, mag, calcium levels[2]
- May observe hyperphosphatemia, hypocalcemia, hypomagnesemia
- High risk patients: renal impairement, abnormal gut motility, IBD, elderly, cardiac co-morbidities[3][4]
Gastrografin PO
- Gastrografin through NG or OG decreases bowel wall edema and increases bowel motility[5]
- Diagnostic and therapeutic[6]
- 100 cc of gastrografin through NG tube
- Transit may be observed through serial radiographs
- Contrast within the large bowel within 24 hrs suggest partial small bowel obstruction
- Contrast failing to reach large bowel within 24-48 hrs suggests complete obstruction, requiring laparotomy
- Therapeutic, may reduce necessary operative rate by ~75%[7]
- Avoid barium as it becomes inspissated in bowel, causing complete obstruction[8]
- If perforation occurs with barium, leakage can be lethal
- Gastrografin is water-soluble and relatively safer if perforation occurs
- Be aware that anaphylactoid reactions and serious aspirations have occurred rarely with Gastrografin, however[9]
Disposition
- Normally outpatient
See Also
References
- ↑ Portalatin M and Winstead N. Medical Management of Constipation. Clin Colon Rectal Surg. 2012 Mar; 25(1): 12–19.
- ↑ Farah R. Fatal acute sodium phosphate enemas intoxication. Acta Gastroenterol Belg. 2005 Jul-Sep;68(3):392-3.
- ↑ Reedy JC, Zwiren GT. Enema-induced hypocalcemia and hyperphosphatemia leading to cardiac arrest during induction of anesthesia in an outpatient surgery center. Anesthesiology. 1983 Dec;59(6):578-9.
- ↑ Korzets A, Dicker D, Chaimoff C, Zevin D. Life-threatening hyperphosphatemia and hypocalcemic tetany following the use of fleet enemas. J Am Geriatr Soc. 1992 Jun;40(6):620-1.
- ↑ Assalia A, Schein M, Kopelman D, et al. Therapeutic effect of oral Gastrografin in adhesive, partial small-bowel obstruction: A prospective randomized trial. Surgery 1994; 115: 433-437.
- ↑ Chen SC, Lin FY, Lee PH, et al. Water-soluble contrast study predicts the need for early surgery in adhesive small bowel obstruction. Br J Surg 1998; 85: 1692-1694.
- ↑ Choi HK et al. Therapeutic Value of Gastrografin in Adhesive Small Bowel Obstruction After Unsuccessful Conservative Treatment: A Prospective Randomized Trial. Annals of Surgery. 2002;236(1).
- ↑ Choi HK et al. Therapeutic Value of Gastrografin in Adhesive Small Bowel Obstruction After Unsuccessful Conservative Treatment: A Prospective Randomized Trial. Annals of Surgery. 2002;236(1).
- ↑ Skucas J. Anaphylactoid reactions with gastrointestinal contrast media. AJR Am J Roentgenol 1997; 168: 962-964.