An endoscopic technology recommended by Chinese physicians to treat appendicitis

Even physicians of digestive endoscopy were shocked at the beginning when they heard that appendicitis could be treated by colonoscopy.

In fact, physicians in China have done a lot of research and practices in this regard.

In 2009, Prof. Liu Bingrong, who was in the 2^nd Affiliated Hospital of Harbin Medical University, created ERAT operation firstly in the world. Presently, ERAT technology has been developed and improved during practice. 

Presently, this technology has been carried out in 27 provinces in China, with over 3200 cases.  Until the end of 2019, Prof. Liu has collected information of 1576 patients with ERAP operation. The statistics result indicates that the successful rate of ERAT operation is 93.6% , and the effective rate is 95.9%. The recurrence rate was 6.2% during follow-up.

Is the appendix really useless?

Surgical resection of acute appendicitis remains controversial because the appendix is rich in lymphoid tissue that is involved in the body's immunity. Studies have shown that patients shall have 14% higher incidence to have colon tumors after appendectomy than those without appendectomy.

The appendix can also secrete a variety of digestive enzymes and hormones that promote intestinal motility, and regulate the balance of intestinal flora.

Medical knowledge is constantly expanding, and although we don't yet have a clear idea of what the appendix does, no one wants to perform a surgical procedure easily. So we should strictly check the appendiceal excision indications.

The development of ERAT

Endoscopic retrograde appendicitis therapy，ERAT, was inspired by ERCP technology. According to the theory of appendix lumen obstruction and bacterial infection of appendicitis, the pathogenesis of acute appendicitis was obstruction of appendix cavity and secondary bacterial infection. Therefore these two aspects are ERAT treatment principles.  The physicians flush the appendix cavity with antibiotics and implant stent, so as to relieve obstruction and treat bacteria infection.

Under the supervision of radiation and guided by colonoscopy, the inflammatory secretions were rinsed, drained, removed and electrocuted to the obstruction of the appendix cavity through the guide wire/catheter technology (Seldinger technology), so as to relieve the obstruction, reduce the pressure in the appendiceal cavity and prevent the appendix ischemia and necrosis caused by the high pressure in the appendix, so as to achieve the therapeutic purpose.

Indications of ERAT

Patients with acute and chronic appendicitis caused by various reasons without necrosis and perforation, including acute appendicitis with stercorolith obstruction, recurrent appendicitis, high pressure in the cavity of pyogenic appendix, local stenosis of the appendix cavity, and local wrapping of the perforated abscess of the appendix, etc.

Surgical excision is still recommended for patients with suspected appendiceal gangrenous perforation.

These conditions should be met :(1) the disease time is less than 48h; (2) the clinical manifestations are metastatic right lower abdominal pain or acute parasympathetic right lower abdominal pain; (3) fixed point pain by pressure on Mcburney point in the right lower abdomen, accompanied by rebound pain; (4) body temperature lower than 39 ℃; (5) white blood cell count <20×109/L; (6) stable vital signs; (7) acute abdominal diseases such as acute cholecystitis, pancreatitis, urinary calculi and gynecological emergencies are excluded.

Steps of ERAT

(1) Endoscopic appendiceal intubation

(2) Decompression of appendiceal cavity:

After successful appendiceal intubation, the fester in the appendiceal cavity should be rapidly drawn out to reduce the pressure in the appendiceal cavity and prevent the appendiceal ischemia and necrosis caused by the increased pressure in the appendiceal cavity.

(3) Endoscopic retrograde appendectomy:

After decompression of the appendiceal cavity, an appropriate amount of contrast agent was injected through the catheter to show the conditions in the appendiceal cavity, such as stenosis and defect.

(4) Lithotomy by balloon or basket

The stercorolith was removed by balloon catheter or stone basket. The black arrow indicates that stercorolith was taken out.

(5) plastic stent implantation and drainage:

After the full removal of the stercorolith, the plastic stent is placed for abscess drainage and further appendiceal cavity flushing (normal saline + antibiotics).

The stent was removed under colonoscopy about a week after operation.

Relative advantages of ERAT compared with appendectomy

(1) After decompression of the appendiceal cavity with endoscopic appendiceal intubation, the patient's pain symptoms can be rapidly relieved, and the patient can immediately resume daily activities to avoid incision pain after surgery.

(2) ERAT technique has little trauma, no scar on the body surface, fast and convenient operation. Preliminary clinical results showed that the patient had no complications such as bleeding, perforation and periappendiceal abscess formation. ERAT technology can be developed in outpatient clinic in the future, saving medical resources.

(3)ERAT technology retains the potential physiological functions of the appendix.