Inflammatory Bowel Disease

Introduction

Crohn's Disease

Problem -- Crohn's Disease

Crohn's Disease is a poorly understood condition affecting the GI tract that causes inflammatory changes resulting in a myriad of symptoms and problems--some of which can lead to diving problems! The cause of this group of diseases is unknown: immunologic factors have been extensively examined; possible infectious agents have included various enteric bacteria, viruses, and chlamydiae, and attention has most recently focused on mycobacteria; dietary factors (including chemicals and the fiber-poor diet consumed in modern developed countries) have also been considered. Not one of these hypotheses has been proved.

Diving Concerns

Condition  Related
The main difficulty divers would have is with a blockage or perforation and fistulas with air-trapping; this could lead to subsequent rupture due to the changes that take place in association with Boyle's law. Diving would be unwise during the active phase of the condition due to chronic diarrhea, abdominal pain, fever, anorexia and weight loss. Obstruction, fistulas and abscess formation are common complications of inflammation; intestinal bleeding, perforation, and small bowel cancer develop rarely.

  Treatment Related
No specific therapy is known. Anticholinergics and diphenoxylate 2.5 to 5 mg, loperamide 2 to 4 mg, deodorized opium tincture 0.5 to 0.75 mL (10 to 15 drops), or codeine 15 to 30 mg, given orally (ideally before meals) up to qid, may relieve cramps and diarrhea. These drugs can alter levels of consciousness and decrease decision making ability and are therefore adverse to diving.

Metronidazole 1 to 1.5 gm/day has been shown to be beneficial in CD, especially in Crohn's colitis and has proved particularly useful for treating perianal lesions. Neuropathy manifested chiefly by paresthesias is a common, potentially serious side effect of long-term use and can cause confusion with the neuropathic effects of a decompression accident.

Corticosteroid therapy is useful in the acute stages of CD.  Aseptic hip necrosis can occur with long-term steroid administration and could be confused with dysbaric osteonecrosis associated with diving.

Immunosuppressive drugs are useful but the deadly combination of diminished immune response and alien marine bacteria must be taken into account with any decisions concerning diving with Crohn's patients on these drugs.

Surgery is usually necessary when recurrent intestinal obstruction or intractable abscesses or fistulas are present. Resection of the grossly involved bowel may ameliorate symptoms indefinitely but does not cure the disease. Thus, surgery should not be done unless specific complications or failure of medical therapy make it necessary. When operations have been required, however, most patients consider their quality of life to have been improved. HBOT has been shown to benefit certain patients with perianal Crohn's disease.

The continent ileostomy or ileal pouch are contraindications to diving due to the inability of gas in these structures to escape the effects of pressure changes. There is considerable risk of rupture of the pouch during ascent due to gas expansion.

Diver Related

Crohn's patients are more prone to be taking multiple drugs and medicines, some of which have effects that are adverse to diving. These should be listed and evaluated prior to allowing diving. See web page at http://scuba-doc.com/drugsdiv.htm .

Advising the Diver 
Potential for injury from future diving

Diving itself does not affect Crohn's disease one way or the other--just the effects of pressure on the complications of the disease and the alterations that medications cause in the ability of the body to ward off infection.

 
   Dive or not dive

Diving should be considered if the person is in good general physical condition, has quiescent disease, no evidence of air-trapping and is off medications that are adverse to diving.

Some consideration should be given to "need to dive" over riders; such as previously certified divers returning to diving, divemasters and instructors. Persons wanting to become certified should probably be discouraged from diving due to the long term course of Crohn's Disease.
The presence of an ileal pouch or continent ileostomy would prevent diving.

Chronic Ulcerative Colitis

The disease usually begins in the rectosigmoid area and may extend proximally, eventually to involve the entire colon, or it may include most of  the large bowel at once.  Crypt abscesses, epithelial necrosis, and mucosal ulceration ultimately develop.

Diving Concerns

Condition  Related

Systemic symptoms are mild or absent. If the process extends proximally,stools become looser and the patient may have 10 to 20 bowel movements/day, often with severe cramps and distressing urge to defecate, without respite at night. The stools may be watery and contain pus, blood, and mucus; they frequently consist almost entirely of blood and pus. Malaise, fever, anemia, anorexia, weight loss, leukocytosis, hypoalbuminemia, and elevated sedimentation rate may be present with extensive activecolitis. It should be apparent that diving would be contraindicated in the midst of an acute flare-up of this condition. In particular, it would not be good to be in a remote destination with this occurrence. 

Hemorrhage is the most common local complication. In toxic colitis, a particularly severe local complication, transmural extension of the ulcerative process results in localized ileus and peritonitis. As the toxic colitis progresses, the colon loses muscular tone and within a matter of days or even hours begins to dilate. This is called toxic megacolon.

Risk of colon cancer is increased in patients with long-standing, extensive ulcerative colitis; such patients merit surveillance for early warning signs. Extracolonic complications include peripheral arthritis, ankylosing spondylitis, sacroiliitis, anterior uveitis, erythema nodosum, pyoderma gangrenosum, episcleritis, and, in children, severely retarded growth and development.

Treatment Related

Anticholinergics or low doses of diphenoxylate, deodorized opium tincture, loperamide or codeine may be required for more intense diarrhea. All these antidiarrheal agents must be used with extreme caution in more severe cases, lest toxic dilation be precipitated. The effects of these drugs on the alertness of the diver would certainly be a consideration in disallowing diving in these individuals.

Azathioprine, 6-mercaptopurine, and cyclosporine have been used in the treatment of ulcerative colitis, but their long-term risk/benefit ratios have not been clearly established. Decreased immune response is hazardous to the diver in the alien marine bacterial environment.

Toxic colitis is a grave emergency. If intensive medical measures do not produce definite improvement within 24 to 48 h, immediate surgery is required or the patient may die from perforation and attendant sepsis.

Emergency colectomy is indicated for massive hemorrhage, fulminating toxic colitis, or perforation. Subtotal colectomy with ileostomy and rectosigmoid mucous fistula is usually the procedure of choice, since total proctocolectomy with abdominoperineal resection is more than most critically ill patients can tolerate. There is no contraindication to diving in these situations after appropriate postoperative healing (3 months). An ileostomy and a mucous fistula do not abrogate Boyle's Law and are not a risk for perforation.

Removal of the entire colon and rectum permanently cures chronic ulcerative colitis. Permanent ileostomy has been the traditional price of this cure, although various alternatives (eg, the continent ileostomy or especially endorectal  "pull-through" procedures) are usually chosen. The cosmetic details of the surgery are less critical than the curative nature of colectomy in a disease as serious as ulcerative colitis. The continent ileostomy or ileal pouch are contraindications to diving due to the inability of gas in these structures to escape the effects of pressure changes. There is considerable risk of rupture of the pouch during ascent due to gas expansion. Clever divers have placed in-dwelling catheters in the pouch for equalization of the gas.

Diver Related

Dehydration, hypokalemia and anemia are all hazards to the diver. Dehydration is definitely associated with increased incidence of DCS; hypokalemia is associated with increased arrhythmias and the oxygen-carrying potential of the diver with anemia is diminished. Divers who have not recovered from the effects of surgery should not dive until they have completely recovered and have the approval of their physicians.

Advising the Diver 

Potential for injury from future diving

Factors adverse to diving:
Anemia
Weakness, inanition
Dehydration
Low potassium
Medications that obtund the sensorium
Medications that alter the immune system
Barotrauma to closed air spaces [ileal pouch].


Dive or not dive

Diving itself does not affect chronic ulcerative colitis, one way or the other--just the effects of pressure on the complications of the disease and the alterations that medications cause in the ability of the body to ward off infection. Thus, if a person has had surgery and has recovered completely from it's effects - there should be little reason to not dive.