Flat Stomas: Not Normal and Require Intervention
A flat or flush stoma is not ideal and predisposes patients to significant complications, particularly leakage and skin excoriation, which can dramatically impair quality of life. 1
Why Flat Stomas Are Problematic
A properly constructed stoma should protrude above the skin level to prevent effluent from contacting the peristomal skin. Specific height requirements vary by stoma type:
- Ileostomies and loop ileostomies: Should protrude at least 20 mm above skin level 2
- Colostomies: Should protrude at least 5 mm above skin level 2
Almost all patients with ileostomies lower than 20 mm experience leakage and skin problems, and half of patients with colostomies lower than 5 mm develop these complications. 2
Clinical Consequences of Flat Stomas
Primary Complications
- Leakage: The most common and dreaded stomal complication, occurring when the stoma sits flush with the skin 1
- Skin excoriation: Affects 54-60% of patients with inadequate stoma height, caused by repetitive effluent contact with peristomal skin 1, 2, 3
- Pouching difficulties: Flat configuration makes appliance adherence challenging 1
- Pain and financial hardship: From frequent appliance changes and specialized equipment needs 1
Risk Factors That Worsen Flat Stoma Outcomes
Certain patient factors compound the problems of a flush stoma 1:
- Obesity
- Placement within a skin crease
- Loop configuration
- Liquid effluent (ileostomies or chronic diarrhea)
Management Strategies
Conservative Measures
When faced with a flat stoma, implement these interventions 1:
- Thicken stool output: Use antidiarrheals to create more solid effluent
- Specialized pouching techniques:
- Convex appliances to increase effective stoma height
- Ostomy belts for additional support
- Paste or barrier rings to build up the peristomal area
- Application techniques:
- Heat appliance with hair dryer before application
- Lie flat for several minutes after application
- Ensure peristomal skin is completely dry
- Apply stomal powder followed by skin sealant on excoriated areas
- Proper sizing: Cut appliance opening one-eighth inch larger than stoma diameter 1
When Surgery Is Indicated
Stoma retraction (which presents as a flat or recessed stoma) may require surgical revision if conservative measures fail. 4 This is particularly true when:
- Leakage cannot be controlled with pouching modifications
- Severe skin excoriation persists despite optimal management
- The stoma becomes truly recessed below skin level
Prevention Is Key
The best strategy is prevention through meticulous surgical technique and preoperative planning. 1
Critical preventive measures include 1, 5:
- Preoperative marking by a stomatherapist: Assess abdomen in multiple positions (sitting, standing, lying)
- Avoid placement in skin creases or within the rectus muscle
- Ensure adequate stoma height at creation: This is the surgeon's responsibility and directly impacts patient outcomes 2
Common Pitfall
Do not dismiss a flat stoma as "normal postoperative appearance" that will improve with time. Stoma height should be assessed at each appliance change for the first 8 weeks, as the stoma will shrink during this period. 1 Early identification of inadequate height allows for prompt intervention before severe skin complications develop.
Clinical Context
While flat stomas are not normal, they occur more commonly in emergency surgery when optimal preoperative planning is impossible. 3 However, even in emergency settings, surgeons should strive to create adequate stoma projection, as the complications of a flush stoma significantly impact morbidity and quality of life through chronic skin problems, pain, and lifestyle limitations. 1, 2