Less Irrigation May Reduce Abscesses After Appendectomy

CHICAGO – High-volume intra-abdominal irrigation significantly increased the risk of postoperative abscess in a study of 327 appendectomy patients and led investigators to conclude that use of irrigation should be limited in these patients.

The classical thinking that irrigation during appendectomies washes away bacteria is changing, as additional data suggest that irrigation might create pockets of fluid that can lead to the formation of abscesses, Dr. Esteban Gnass said at the annual clinical congress of the American College of Surgeons.

Previous studies have shown that postoperative abscess (POA) formation significantly increases the length of a patient’s hospital stay and hospital costs, said Dr. Gnass of Riverside County Regional Medical Center in Moreno Valley, Calif.

To determine the association between irrigation during surgery and POA formation, he and his colleagues reviewed data from 265 laparoscopic and 62 open procedures conducted between January 2009 and June 2011. There were no significant demographic differences between patients in the two procedure groups. Patients also were subdivided according to perforated vs. nonperforated and irrigated vs. nonirrigated.

A total of 17 postoperative abscesses were observed, all of which occurred in irrigated patients. In addition, 88% of the postoperative abscess cases involved at least 500 mL of irrigation. "Large irrigation volumes carried a higher risk of POA," Dr. Gnass said.

After controlling for multiple variables, the investigators found that both irrigation volume and perforation were significantly associated with abscess formation.

In both the laparoscopic and open groups, 100% of perforated patients received at least 500 mL of irrigation, compared with 75% of the nonperforated patients in the laparoscopy group and 0% of nonperforated patients in the open group.

POA rates and perforation rates were not significantly different between laparoscopic and open groups (5% vs. 4%, and 25% vs. 37%, respectively).

On further analysis of the POA cases only, perforation rates were not significantly different between laparoscopic and open groups (72% vs. 67%).

"Surgical technique was not associated with abscess formation," Dr. Gnass noted.

Among the perforated cases only, postoperative abscesses developed in 18% of those who received at least 500 mL of irrigation and in none of those who received less than 500 mL of irrigation.

More research in the form of a prospective, randomized trial is needed to confirm the results, but based on the current findings, "we can suggest limiting the use of irrigation to 500 cc or less" in appendectomy procedures, Dr. Gnass said.

He reported having no relevant financial disclosures.

CHICAGO – High-volume intra-abdominal irrigation significantly increased the risk of postoperative abscess in a study of 327 appendectomy patients and led investigators to conclude that use of irrigation should be limited in these patients.

The classical thinking that irrigation during appendectomies washes away bacteria is changing, as additional data suggest that irrigation might create pockets of fluid that can lead to the formation of abscesses, Dr. Esteban Gnass said at the annual clinical congress of the American College of Surgeons.

Previous studies have shown that postoperative abscess (POA) formation significantly increases the length of a patient’s hospital stay and hospital costs, said Dr. Gnass of Riverside County Regional Medical Center in Moreno Valley, Calif.

To determine the association between irrigation during surgery and POA formation, he and his colleagues reviewed data from 265 laparoscopic and 62 open procedures conducted between January 2009 and June 2011. There were no significant demographic differences between patients in the two procedure groups. Patients also were subdivided according to perforated vs. nonperforated and irrigated vs. nonirrigated.

A total of 17 postoperative abscesses were observed, all of which occurred in irrigated patients. In addition, 88% of the postoperative abscess cases involved at least 500 mL of irrigation. "Large irrigation volumes carried a higher risk of POA," Dr. Gnass said.

After controlling for multiple variables, the investigators found that both irrigation volume and perforation were significantly associated with abscess formation.

In both the laparoscopic and open groups, 100% of perforated patients received at least 500 mL of irrigation, compared with 75% of the nonperforated patients in the laparoscopy group and 0% of nonperforated patients in the open group.

POA rates and perforation rates were not significantly different between laparoscopic and open groups (5% vs. 4%, and 25% vs. 37%, respectively).

On further analysis of the POA cases only, perforation rates were not significantly different between laparoscopic and open groups (72% vs. 67%).

"Surgical technique was not associated with abscess formation," Dr. Gnass noted.

Among the perforated cases only, postoperative abscesses developed in 18% of those who received at least 500 mL of irrigation and in none of those who received less than 500 mL of irrigation.

More research in the form of a prospective, randomized trial is needed to confirm the results, but based on the current findings, "we can suggest limiting the use of irrigation to 500 cc or less" in appendectomy procedures, Dr. Gnass said.

He reported having no relevant financial disclosures.

CHICAGO – High-volume intra-abdominal irrigation significantly increased the risk of postoperative abscess in a study of 327 appendectomy patients and led investigators to conclude that use of irrigation should be limited in these patients.

The classical thinking that irrigation during appendectomies washes away bacteria is changing, as additional data suggest that irrigation might create pockets of fluid that can lead to the formation of abscesses, Dr. Esteban Gnass said at the annual clinical congress of the American College of Surgeons.

Previous studies have shown that postoperative abscess (POA) formation significantly increases the length of a patient’s hospital stay and hospital costs, said Dr. Gnass of Riverside County Regional Medical Center in Moreno Valley, Calif.

To determine the association between irrigation during surgery and POA formation, he and his colleagues reviewed data from 265 laparoscopic and 62 open procedures conducted between January 2009 and June 2011. There were no significant demographic differences between patients in the two procedure groups. Patients also were subdivided according to perforated vs. nonperforated and irrigated vs. nonirrigated.

A total of 17 postoperative abscesses were observed, all of which occurred in irrigated patients. In addition, 88% of the postoperative abscess cases involved at least 500 mL of irrigation. "Large irrigation volumes carried a higher risk of POA," Dr. Gnass said.

After controlling for multiple variables, the investigators found that both irrigation volume and perforation were significantly associated with abscess formation.

In both the laparoscopic and open groups, 100% of perforated patients received at least 500 mL of irrigation, compared with 75% of the nonperforated patients in the laparoscopy group and 0% of nonperforated patients in the open group.

POA rates and perforation rates were not significantly different between laparoscopic and open groups (5% vs. 4%, and 25% vs. 37%, respectively).

On further analysis of the POA cases only, perforation rates were not significantly different between laparoscopic and open groups (72% vs. 67%).

"Surgical technique was not associated with abscess formation," Dr. Gnass noted.

Among the perforated cases only, postoperative abscesses developed in 18% of those who received at least 500 mL of irrigation and in none of those who received less than 500 mL of irrigation.

More research in the form of a prospective, randomized trial is needed to confirm the results, but based on the current findings, "we can suggest limiting the use of irrigation to 500 cc or less" in appendectomy procedures, Dr. Gnass said.

He reported having no relevant financial disclosures.