An anorectal fistula is an abnormal channel formed by infection, injury, foreign body and other pathological factors in the perianal space that connects to the skin around the anus, and is called anorectal fistula, or anal fistula for short. Its clinical manifestations are characterized by anal sclerosis, repeated local rupture and pus flow, pain, dampness, and itching. It is a common anorectal disease and has a high recurrence rate. It can occur in different genders and ages, mainly in young adults aged 20-40 years, with more men than women.
The principle of surgery is to remove or incise the entire fistula and, if necessary, to remove the inflammatory scar tissue around the fistula, creating an open wound that is wide at the top and narrow at the bottom, leaving no residual cavity so that the incision can grow and heal outward from the base, avoiding the formation of the fistula again. The correct classification of anal fistulas is again of great relevance to the choice of surgical approach.
Anal fistulas are generally classified into four categories.
1. low simple fistulas, which have only one fistula and pass below the depth of the external sphincter, with the internal opening near the anal sinus.
2. low complex anal fistulas with a fistula that passes below the deep external sphincter, with more than two external ports and fistulae and an internal port in the sinus area (including multiple fistulas)
3, high simple anal fistula with only one fistula tract, with the fistula crossing above the deep external sphincter and the internal orifice located in the anal sinus site.
4. high complex anal fistula with more than two external orifices and fistulas with branches, whose main tubes pass above the deep external sphincter and have one or two or more internal orifices.
After the classification is basically clear, only then can the different surgical methods be correctly selected. Regardless of the surgical method used, the following key issues must be mastered.
(1) Identifying the correct internal orifice and treating it correctly is the key to successful surgery.
(2) Proper treatment of the anorectal ring and sphincter: fistulas above the deep external sphincter or through the anorectal ring should not be directly incised, but should be hooked up so that they are slowly incised to prevent anal incontinence.
(3) Proper treatment of the caudal ligament; the caudal ligament can be cut longitudinally, not transversely, and if it does need to be cut, the two severed ends should be re-sutured and fixed so as not to cause forward displacement and collapse.
(4) The surgical wound must be “small inside and big outside” in order to facilitate drainage.
(5) During surgery, the treatment of the fistula wall tissue should be partially preserved rather than completely removed. The first thing you need to do is to take a look at the results of the surgery.
Postoperative medication change accounts for half of the credit. In the postoperative wound change, we must identify the yin and yang, the old and new, the presence of rotten flesh, pterygium, pus, etc., and adopt the methods of removing rot and creating new, clearing heat and dampness, and creating muscle to close the mouth, that is, “identify the wound change”. As the postoperative wound is an open wound, the treatment of the wound should take into account the nature and amount of exudate and the growth of the wound by using different herbal baths and dressing changes.
Postoperative wound dressing change needs to pay attention to.
(1) Postoperative controlled defecation for 48h according to the trauma, fumigation sitz bath and drug change after each defecation.
(2) The drainage gauze should be placed both to drain freely and tightly to the bottom of the wound and the incised internal opening to ensure the growth of the wound granulation from the inside out.
(3) The trauma should be changed once a day. For the unincised sinus tract with open window, it should be carefully flushed and fixed with pressure daily.
(4) Tighten the rubber band tightening line at the appropriate time according to the growth of the trauma.
For delayed wound healing, consider the following factors for management.
(1) After a period of use of one healing-promoting drug, other healing-promoting drugs can be used for dressing change, such as rehabilitation new liquid and muscle-generating cream.
(2) If tuberculous fistula is considered, topical application of anti-tuberculosis drugs can be used for diagnostic treatment, such as isoniazid or rifampin powder sprinkled on the wound surface for dressing change.
(3) Wound pseudo-healing, pay attention to the observation of the wound, conduct careful examination, and trim the wound if necessary.
(4) When the shape of the wound is not conducive to wound drainage and wound healing, trim as necessary, such as granulation tissue above the wound surface to be trimmed.
(5) Wound edema: you can use saturated magnesium sulfate sitz bath, or use grass rhinoceros fluid infusion tablets orally to reduce swelling, and trim the edema site under local anesthesia if necessary.