Prophylaxis of infection after appendicectomy: a survey of current surgical practice

Prophylactic intraabdominal drains do not confer benefit in pediatric perforated appendicitis: Results from a quality improvement initiative

BACKGROUND/PURPOSE

Prophylactic, intraabdominal drains have been used to prevent intraabdominal abscess (IAA) after perforated appendicitis. We hypothesized that routine drain placement would reduce the IAA rate in pediatric perforated appendicitis.

METHODS

A 27-month quality improvement (QI) initiative was conducted: closed-suction, intraabdominal drains were placed intraoperatively in pediatric (age < 18) perforated appendicitis patients. QI patients were compared to controls admitted during the preceding 8 months and following 4 months. The primary outcome was 30-day IAA rate. Univariate and multivariate analyses were performed.

RESULTS

Two hundred seventy QI patients were compared to 109 controls. There was 100% compliance during 21 of 27 months of the QI initiative; only 7 QI patients did not receive drains. IAA occurred in 20.0% of QI patients and 22.9% of control (p = 0.52). After adjustment, the QI initiative was not associated with reduced odds of IAA (OR 0.83, 95% CI 0.48-1.44). Median length of stay was longer in QI patients during the index admission (p = 0.03) and over 30 postoperative days (p = 0.03), but these relationships did not persist after adjustment.

CONCLUSIONS

A QI initiative investigating prophylactic, intraabdominal drain placement in perforated appendicitis did not reduce the IAA rate. We recommend against routine drain placement in pediatric perforated appendicitis.

LEVEL OF EVIDENCE

Level III.

Diagnosis and management of acute appendicitis. EAES consensus development conference 2015

Unequivocal international guidelines regarding the diagnosis and management of patients with acute appendicitis are lacking. The aim of the consensus meeting 2015 of the EAES was to generate a European guideline based on best available evidence and expert opinions of a panel of EAES members. After a systematic review of the literature by an international group of surgical research fellows, an expert panel with extensive clinical experience in the management of appendicitis discussed statements and recommendations. Statements and recommendations with more than 70 % agreement by the experts were selected for a web survey and the consensus meeting of the EAES in Bucharest in June 2015. EAES members and attendees at the EAES meeting in Bucharest could vote on these statements and recommendations. In the case of more than 70 % agreement, the statement or recommendation was defined as supported by the scientific community. Results from both the web survey and the consensus meeting in Bucharest are presented as percentages. In total, 46 statements and recommendations were selected for the web survey and consensus meeting. More than 232 members and attendees voted on them. In 41 of 46 statements and recommendations, more than 70 % agreement was reached. All 46 statements and recommendations are presented in this paper. They comprise topics regarding the diagnostic work-up, treatment indications, procedural aspects and post-operative care. The consensus meeting produced 46 statements and recommendations on the diagnostic work-up and management of appendicitis. The majority of the EAES members supported these statements. These consensus proceedings provide additional guidance to surgeons and surgical residents providing care to patients with appendicitis.

Oral metronidazole as antibiotic prophylaxis for patients with nonperforated appendicitis

Background

The rate of wound infection after appendectomy without antibiotic prophylaxis is 10%–30%. The role of prophylactic antibiotic therapy in nonperforated appendicitis is still controversial. Metronidazole is against anaerobic organisms and its bioavailability after oral and parenteral administration has been shown to be similar. The objective of the present study is to compare the infective complications rate after open appendectomy for nonperforated appendicitis receiving either oral or intravenous metronidazole as prophylaxis.

Methods and Materials

From June 2007 to July 2009 in a randomized controlled trial, 204 patients with nonperforated appendicitis underwent an open appendectomy; 122 male and 82 female with mean age of 25 years. Among these, 102 (case group) received oral metronidazole and in 102 (control group) metronidazole was administered intravenously before surgery. The rate of wound infection and duration of the postoperative hospital stay was studied in the two groups.

Results

The rate of wound infection was not significantly different in the two groups. (6% and 4% in study and control group, respectively, P = 0.861). Also the hospital stay was equal in two groups (2.3 days and 2.7 days in study and control group, respectively, P = 0.293).

Conclusion

Single dose of oral metronidazole prior to operation can provide a sufficient prophylaxis for nonperforated appendicitis; so, it can be substitute the parental route of antibiotic administration.

Can Oral Metronidazole Substitute Parenteral Drug Therapy in Acute Appendicitis?: A New Policy in the Management of Simple or Complicated Appendicitis with Localized Peritonitis: A Randomized Controlled Clinical Trial

To demonstrate the efficacy of oral metronidazole (OM) in simple or complicated appendicitis with localized peritonitis, a randomized prospective study was carried out in 1083 patients, ranging in age from 4 to 50 years (mean age, 21.38).

The patients were randomly divided into two groups. The study group (SG) (524 patients) received OM (500 mg for adults, 7–10 mg/kg if less than 15 years) 2–3 hours before operation. The drug was continued 4 to 5 hours after operation, every 8 hours, for three doses if the appendix was mild to severely inflamed. In the case of complicated appendicitis (114 patients), the same dose was given for 3 to 6 days, depending on the absence or presence of pus. Ceftizoxime was administered to the control group (CG) (559 patients) 2 to 3 hours before operation and then postoperatively every 6 hours for three doses if the appendix was mild to severely inflamed. The complicated cases in the CG (120 patients) received a combination of penicillin, chloramphenicol, and gentamicin for 3 to 6 days, depending on the absence or presence of pus.

The serum concentration of metronidazole measured in 43 patients was at bactericidal level in 40 (mean ± SD standard deviation, 10.65 ± 4.89 μg/mL).

The rate of wound infection was not significantly different in the SG and the CG with the same degree of pathology (3.17% vs 2.96% if uncomplicated; 15.78% vs 14.16% if complicated, respectively). Pelvic collection occurred in four adults and one child in the CG with perforated appendicitis (4.16%). The same complication developed in two adults and two children in the SG with perforated appendicitis (3.5%). All six adults and one of the children in the SG had to be re-explored, whereas the remaining two children responded to conservative management (OM and gentamicin). In uncomplicated cases, hospital stay and hospital charge were both almost the same in both groups. However, length of hospitalization was nearly 1 day shorter and hospital cost per day was about 30 per cent less in complicated cases in the SG as compared with the CG.

Conclusively, OM may not only substitute parenteral antibiotics in acute appendicitis as a prophylactic agent, but it may also be used as a cost-effective drug and is more convenient to the patient.

Preventing wound infection after appendicectomy: a review

An exponential increase in the number of published prospective studies reflects both a continuing interest in, and a lack of consensus on, the optimal prophylaxis of wound sepsis after appendicectomy. Review of the literature over the last 25 years leads us to emphasize both the importance of adequate study size and of stratification of the severity of the sepsis found at operation. For critical comparison of prophylactic regimens the high percentage of wound infections disclosed after discharge from hospital must be taken into account. Antibiotics reduce the frequency of wound sepsis and although low wound sepsis rates have been reported with systemic antibiotics active against only anaerobes, the cumulative evidence favours a spectrum of antibacterial activity against both aerobic and anaerobic organisms. Topical antiseptics have no significant effect but topical antibiotics are beneficial. Wide variations in outcome for similar antibiotic regimens reflect the importance of technical factors in determining the frequency of wound sepsis.

Cefotaxime lavage in children undergoing appendicectomy

In an attempt to reduce postoperative sepsis, a series of randomised, double-blind studies was begun in 1982, using cefotaxime as backbone therapy. Up to 1985 (stages I and II), the best results were obtained using a combination of cefotaxime (75 mg/kg intravenously in 3 doses at 12-hourly intervals) plus metronidazole (10 mg/kg intravenously in 3 doses), both drugs administered 1 hour before surgery (preoperatively) or at anaesthetic induction (peroperatively). In 300 consecutive cases, the wound infection rates were 1% in uncomplicated acute appendicitis and 5% in perforated/gangrenous appendices. The present study (stage III) reports the findings in 401 consecutive patients: 215 treated with the above regimen, either pre- or perioperatively (group 1) and 186 who additionally had peritoneal lavage with cefotaxime 2 g/L during surgery (group 2). There were 16 wound infections overall, 2 among patients administered prophylaxis preoperatively and 14 in those administered prophylaxis perioperatively. All produced mixed cultures, with Escherichia coli, Streptococcus milleri and Bacteroides fragilis predominating. The overall figures for postoperative sepsis are 12/215 (5.6%) in the non-lavage group and 8/186 (4.3%) in the lavage group. Among patients with a perforated and/or gangrenous appendix, the wound infection rate was 8/72 (11.1%) in the non-lavage group (group 1) and 4/66 (6.1%) in the lavage group (group 2). Each group had 2 cases of pelvic abscess.

Combined topical povidone-iodine and systemic antibiotics in postappendicectomy wound sepsis

Three hundred and fifteen patients with appendicitis were randomized into two groups. One group received pre-operative systemic gentamicin and metronidazole while the other group received 1 per cent topical povidone-iodine solution in addition to the antibiotics. For early appendicitis including normal and acutely inflamed appendices, only one dose of antibiotics was used. The postoperative wound sepsis was very low in both groups of patients and there was no statistical difference between them. For late appendicitis including gangrenous and perforated appendices, the antibiotics were continued for 7 days. Eight out of 51 patients who had the topical agent developed wound sepsis compared with one out of 52 patients who received no topical agent. This difference is statistically significant (P = 0.03). All wound infections presented within 2 weeks of operation and were deep. Povidone-iodine, 1 per cent, adversely affects the wound infection rate in late appendicitis and should not be used.

Antibiotic costs and prescribing patterns in a recently commissioned Liverpool teaching hospital. Part II: Antimicrobial chemoprophylaxis

All antibiotics prescribed for prophylaxis in a major teaching hospital were prospectively surveyed during 31 consecutive days. Of 2350 patients admitted during that period, 238 (10.1%) received antibiotics for prophylaxis. A total of 1238 operations were performed during the period of study, of which 201 (16.2%) were covered with antibiotics, at a cost of 3472 pounds. The use of prophylaxis increased according to the risk of peri-operative wound contamination, from 15.8% in Class I to 52.4% in Class III operations. The average cost of chemoprophylaxis also increased correspondingly. A further 40 regimens were issued for non-surgical prophylaxis at a cost of 258 pounds. Twenty antibiotics were prescribed either alone or in 37 different combinations for surgical prophylaxis, the most frequent being cephradine (22%), metronidazole (17%), penicillin (12%), and tobramycin (11%). The mean duration of antibiotic administration for all surgical procedures was 6.1 days.

Cefotetan compared with gentamicin and tinidazole in acute abdominal surgery

In a prospective randomised trial 190 consecutive admissions undergoing emergency abdominal surgery were allocated to receive a 24-h peri-operative prophylactic regime of either cefotetan or gentamicin and tinidazole. Wound sepsis developed in 14 patients in each group and one patient in each group developed intra-abdominal abscess. Nine patients in the cefotetan group and 10 patients in the gentamicin and tinidazole group died within 1 month of surgery. The death of one patient in each group was directly related to sepsis. Sixty-five per cent of aerobes isolated at operation were sensitive to cefotetan and 62% sensitive to gentamicin. The in vitro anaerobic cover of tinidazole was complete, whereas 13% of anaerobes isolated at operation were resistant to cefotetan. Anaerobes, predominantly Bacteroides fragilis, were isolated from six of the 14 infected wounds following cefotetan prophylaxis and two of the 14 infected wounds in the gentamicin and tinidazole group. It is therefore recommended that cefotetan should be combined with a nitroimidazole in patients undergoing emergency colo-rectal procedures.

Randomized, prospective, and double-blind trial of new beta-lactams in the treatment of appendicitis

A prospective, randomized, and double-blind study was conducted with 864 patients operated on for appendicitis. In early cases, including normal and acute appendicitis, one dose of antibiotic was given. The rate of postappendectomy septic complications in patients who received cefotaxime, cefoperazone, or moxalactam was very low (about 3%), and there was no statistical difference between the drugs. For late cases, including gangrenous and perforated appendicitis, the antibiotics were continued for 5 days. Moxalactam decreased significantly the septic complications in these patients when compared with the other two drugs. It is safe, free from serious toxic side effects, and more convenient and easier to administer than combination antibiotic therapy. The main disadvantage of moxalactam is its high cost, but this has to be balanced against the savings in nursing time, the cost of monitoring renal function and serum level when aminoglycosides are used, and the reduced usage and manipulation of infusion sets.

Metronidazole and Augmentin in the prevention of sepsis after appendicectomy

Two hundred and fifty patients were admitted to a prospective randomized trial to compare the efficacy of Augmentin with metronidazole in the prevention of sepsis after appendicectomy. Pre-operatively they received either 500 mg metronidazole or 1.2g Augmentin intravenously. Those patients with gangrenous or perforated appendices received eight additional doses of the trial drug at 8 hourly intervals. Overall there were 13 wound infections in the Augmentin group (11 per cent) and 21 in the metronidazole group (18 per cent). The 90 per cent confidence limits for the overall 7 per cent difference in infection rates were +/- 8.5 per cent. There were high rates of wound infection in the gangrenous group (Augmentin 8 per cent versus metronidazole 19 per cent) and especially in the perforated group (Augmentin 33 per cent versus metronidazole 63 per cent). There was no statistically significant difference between the infection rates with the two antibiotics but our study suggests that Augmentin, which is active against both aerobes and anaerobes, may be more effective than metronidazole in reducing wound sepsis after appendicectomy.

Streptococcus milleri in appendicitis in children

A retrospective survey of 253 appendectomies performed on children over a period of one year was carried out. Streptococcus milleri was isolated from pus in 11 (29%) of the 38 children who developed postoperative infections; it was the most commonly identified pathogen in these children. It is concluded that S milleri is a significant pathogen in childhood appendicitis, and that this fact should be taken into account when antibiotic therapy is being planned.

Surgical antimicrobial prophylaxis: principles and guidelines

Antimicrobial prophylaxis for surgical procedures is an area that is recognized as being subject to individual clinical variations. This review gives practitioners some basic principles of rational prophylaxis as defined by the medical literature. In addition, this literature is evaluated and condensed to provide clinicians with guidelines for particular procedures: obstetric, gynecologic, gastric, biliary, colonic, urologic, cardiac, thoracic, vascular, orthopedic and head and neck. Each section concludes with recommendations for the clinically most accepted prophylactic regimens. Antibiotics discussed include not only the older agents, but where good information exists, the newer cephalosporins. The suggested regimens consider efficacy, safety and cost as determinants in rational prescribing. Although research into even shorter, and perhaps more cost-effective, regimens continues, this compilation lists state-of-the-art recommendations.

Prophylaxis of postappendicectomy sepsis by metronidazole and cefotaxime; a randomized, prospective and double blind trial

A randomized, prospective and double blind trial was conducted on 308 patients. Thirty-one out of 102 patients receiving metronidazole developed wound infection compared with 13 out of 103 patients receiving cefotaxime and 14 out of 103 patients receiving metronidazole and cefotaxime. The reduction in the wound sepsis by the use of cefotaxime or a combination of metronidazole and cefotaxime was statistically significant when compared with patients who received metronidazole only. For early cases including normal, acutely inflamed and gangrenous appendices, we gave a single dose of antibiotics just before operation. For late cases with perforation and abscess formation, the antibiotics were continued for 5 days. There was no statistical difference in wound infection between patients who received cefotaxime alone and these who received a combination of metronidazole and cefotaxime.

Prophylaxis of post-appendicectomy sepsis by metronidazole and ampicillin: a randomized, prospective and double-blind trial

Two hundred and eighty-three patients were admitted to a randomized, prospective and double-blind trial of the effect of the addition of ampicillin to metronidazole in the prophylaxis of post-appendicectomy wound sepsis. Nineteen out of 142 patients in the metronidazole and ampicillin group developed wound sepsis compared with 33 out of 141 patients in the metronidazole group. The difference is statistically significant. Early cases, including normal, acutely inflamed and gangrenous appendices, received 2 doses of antibiotics. In late cases with perforation and abscess formation, the antibiotics were continued for 1 week. The difference in wound infection in each of these 2 subgroups was also statistically significant. The commonest organisms isolated from the appendicular fossa and the infected wounds were Escherichia coli and Bacteroides fragilis.

Survey of antibiotic prophylaxis in gastrointestinal surgery in Scotland

The current use of prophylactic antibiotics in gastrointestinal surgery in Scotland was established by postal questionnaire. Twenty-one per cent of surgeons used prophylactic antibiotics during cholecystectomy, 49% during appendicectomy, and 95% for elective colorectal surgery. Two-thirds of those surgeons who did not provide routine antibiotic cover considered that the incidence of wound sepsis in their surgical practice was too low to merit special measures. Most surgeons using prophylaxis chose an appropriate antibiotic. The parenteral route for administration of antibiotic was used by 93% of surgeons during cholecystectomy, 29% during appendicectomy, and 45% in elective colorectal surgery. Most did not prolong cover beyond 24 hours postoperatively. This survey shows that the concepts governing the use of antibiotic prophylaxis have been absorbed into current surgical practice. Most surgeons used appropriate antibiotic regimens; many prefer the parenteral route of administration; most do not prolong cover beyond 24 hours.