Perforation is the most common complication of colonoscopy, with an incidence of 0.3
% after polypectomy [1]. The management of perforation depends on whether there is coexisting peritonitis,
the timing of the diagnosis, and on the patient’s clinical condition and course, but
conservative therapy is seldom indicated [1]
[2]
[3].
We report the case of a 67-year-old man who underwent a screening colonoscopy: several
diverticula and a 35-mm pedunculated polyp were observed in the sigmoid colon. The
polyp was excised by snare polypectomy, using coagulating and cutting current, and
there were no immediate complications. Two days after the procedure the patient developed
diffuse abdominal discomfort that was exacerbated by movement. He continued to eat
and he continued to have bowel movements. He had no fever and no signs of peritoneal
irritation.
Four days later, the clinical picture was the same but there had been a progressive
increase in the patient’s abdominal volume, with a greatly distended, tympanic abdomen.
There were still no signs of peritonitis, however, and laboratory studies were normal.
Abdominal radiography revealed a large pneumoperitoneum (Figure 1). Abdominal computed tomography showed no free intraperitoneal fluid. We did not
perform an enema with water-soluble contrast because of the potential risk of opening
a covered perforation.
Figure 1 Abdominal radiography 6 days after colonoscopy showed a large pneumoperitoneum.
The patient was admitted after surgical evaluation, and managed with a nil-per-mouth
regime and intravenous antibiotics. The persistent pneumoperitoneum was well tolerated
and the patient’s general condition was stable. He was discharged on the third day
and followed closely.
On day 22 post-colonoscopy, the clinical picture persisted. With the patient in the
Trendelenburg position, a paracentesis was performed by inserting a 16-Fr catheter
in the midline, 2 cm below the umbilicus. Gas was promptly released, causing visible
diminution in abdominal volume, with immediate symptomatic improvement. Post-paracentesis
abdominal radiographs demonstrated complete resolution.
Post-colonoscopy pneumoperitoneum most commonly results from bowel perforation and
is usually a life-threatening condition that requires emergency surgery [4]
[5]. In this case the patient had no clinical or laboratory evidence of peritonitis.
His good general condition, the delayed appearance of the pneumoperitoneum, and the
lack of co-morbidity supported the choice of conservative therapy under close observation,
in collaboration with the surgical team.
This patient was an exceptional case in being successfully treated by paracentesis,
which is an unusual choice of treatment in this condition. However, this procedure
cannot be recommended without careful interdisciplinary consultation. The unusual
failure of the pneumoperitoneum to resolve spontaneously may have been related to
the compositon of the gas.
Endoscopy_UCTN_Code_CPL_1AJ_2AC
