Metronidazole and Augmentin in the prevention of sepsis after appendicectomy

Antibiotic prophylaxis for post-operative wound infection in clean elective breast surgery

Antibiotic prophylaxis has been used to good effect in the prevention of post-operative wound infections in patients undergoing gastrointestinal operations. We have assessed the use of a single dose of intravenous antibiotic (Augmentin 1.2 g), given with induction of anaesthesia as prophylaxis, against post-operative wound infection in women undergoing clean, elective breast surgery. Three hundred and thirty-four patients were recruited. Of the 164 receiving antibiotic prophylaxis 29 (17.7%) had wound infections compared with 32 (18.8%) in the placebo group (P=0.79). There were no significant differences in any other post-operative infective complications. Antibiotic prophylaxis is probably not required in clean, elective breast surgery.

Infections and bacteriological data after laparoscopic and open gallbladder surgery

In two hospitals 637 patients undergoing cholecystectomy between June 1989 and June 1993 were entered into a prospective audit. The aim of this study was to determine the incidence of postoperative infections, especially wound infections, after open and laparoscopic biliary surgery and to assess the bacteriological data on these patients. The incidence of minor wound infection was 10.4% (66/637), of major wound infection 3.6% (23/637) and the overall incidence was 14% (89/637). The incidence of wound infection after laparoscopic cholecystectomy was 5.3% (10/189) and all were minor. Significant specific risk factors for developing a wound infection after laparoscopic cholecystectomy were emergency of the operation (P = 0.046) and acute cholecystitis (P = 0.014). Overall, bile cultures were positive in 22%. There were 85 patients (13.3%) with positive bile from the gallbladder. From the laparoscopically operated patients 2.8% had a positive bile culture. The predominant micro-organisms from gallbladder bile were Escherichia coli (56 isolates), Klebsiella spp. (20 isolates) and Streptococcus spp. (16 isolates). There was no relationship between positive gallbladder cultures and wound infection. The consequences of wound infections can be serious and this study showed a morbidity rate comparable with the literature. The incisions used in laparoscopic gallbladder surgery are less susceptible to major problems. This combined with the significantly lower incidence of wound infections after laparoscopic cholecystectomy suggests that routine antibiotic prophylaxis as recommended for biliary surgery in general is now questionable.

An observer blind trial of co-amoxiclav versus cefuroxime plus metronidazole in the prevention of postoperative wound infection after general surgery

A consecutive series of 509 patients undergoing abdominal surgery were entered into a randomized, observer and patient blind, controlled, prospective, study to evaluate the efficiency of co-amoxiclav ('Augmentin', SmithKline Beecham, UK) compared with cefuroxime ('Zinacef', Glaxo, UK) plus metronidazole (Flagyl, M&B, UK) for the prevention of postoperative wound infections. One or three doses of antibiotics were given depending on the type of surgery and operative factors. Co-amoxiclav was given to 230 patients with a total wound infection rate of 5.6% and cefuroxime plus metronidazole were given to 225 patients with a total wound infection rate of 3%. The difference between infection rates was not significant. Both groups were comparable in terms of demographic details, type and duration of surgery, risk factors associated with surgical procedures and postoperative management. Although not statistically significant, a difference in the wound infection rate for those patients undergoing colorectal surgery was seen: 8/69 for the co-amoxiclav group and 2/79 for the cefuroxime/metronidazole group. The estimated cost to our hospital (October, 1993) of one dose of co-amoxiclav was less that half the cost of cefuroxime and metronidazole. This study demonstrates that co-amoxiclav is an effective prophylactic antibiotic for abdominal surgery.

Wound infection in pediatric surgery: a study in 1,094 neonates

In an analysis of 1,433 wounds created in 1,094 neonates admitted to a regional neonatal surgical unit during the period April 1975 to December 1987, the mean incidence of infection was 16.6%. During this time there was an increase in the incidence of infection from 12.5% in the first 6 years to 18.8% in the last 7 years (P < .01). Contaminated wounds had an infection rate of 20.7%, whereas the rate in clean wounds was 11.1% (P < .001). Gestational age and birth weight had no influence on the incidence of wound infection. Increasing wound length (P < .001), increasing duration of operation (P < .001), and contamination at operation (P < .001) were all associated with a higher incidence of infection. Staphylococcal species were the most frequently isolated organisms from all categories of infected wounds (clean, potential, and actual contamination).

A meta-analysis of the use of amoxycillin-clavulanic acid in surgical prophylaxis

The efficacy of amoxycillin-clavulanic acid as antibiotic prophylaxis in surgery has been assessed in numerous clinical studies, chiefly in abdominal and gynaecological surgery. A meta-analysis of 21 trials covering 2685 patients given amoxycillin-clavulanic acid and 2220 patients given comparator regimens is presented. Monotherapy with amoxycillin-clavulanic acid was as effective as the comparators, including combination regimens utilizing gentamicin or metronidazole, in preventing wound infections (median wound infection rates were 6% and 10% respectively). The antibacterial activity of amoxycillin-clavulanic acid covers the broad range of aerobic Gram-negative and anaerobic organisms that have a major role in postoperative infections. In addition, amoxycillin-clavulanic acid may have benefits in terms of convenience, tolerance and cost.

Prospective, randomized study comparing amoxycillin-clavulanic acid and cefamandole for the prevention of wound infection in high-risk patients undergoing elective biliary surgery

The efficacy of amoxycillin-clavulanic acid for prevention of postoperative wound infection was compared with that of cefamandole in 150 patients at risk for infected bile while undergoing elective biliary surgery in a prospective, randomized study. The two groups were comparable for age, sex, risk factors, operative procedures and positive bile cultures. Similar numbers of patients had an uncomplicated postoperative course (amoxycillin-clavulanic acid 70%; cefamandole 73%). Four patients in each group developed wound infection. The incidence of postoperative pneumonia, urinary tract infection and number of days (+/- SD) in hospital (amoxycillin-clavulanic acid 10.1 +/- 4.7; cefamandole 9.7 +/- 5.6) were similar. The efficacy of amoxycillin-clavulanic acid and cefamandole in preventing wound sepsis in high-risk patients undergoing biliary surgery was similar. Economic considerations may favour the use of amoxycillin-clavulanic acid.

A randomized trial of one versus three doses of Augmentin as wound prophylaxis in at-risk abdominal surgery

In a randomized prospective trial of prophylactic antibiotics in at-risk abdominal surgery, one dose of intravenous Augmentin (amoxycillin 250 mg and clavulanic acid 125 mg) on induction has been compared with three 8 hourly doses in 900 patients. Wound infection rates which included minor and delayed infections were very similar in those given one dose: 48/449 (10.7%) compared with those given three doses: 49/451 (10.9%) 95% confidence limits - 4.25% + 3.9%. There were more septic and sepsis-related deaths in those patients given one dose (14 deaths) than in those given three doses (7 deaths) P > 0.1 95% CL - 0.4% + 3.0%. However, there were more very elderly patients in the one dose group: 64% of the deaths were aged over 80 and all but one had an emergency operation. There was no difference in the other outcome measures studied which included non-fatal deep sepsis, length of postoperative hospital stay, duration of postoperative fever or the use of antibiotics for postoperative infection. One dose of a suitable intravenous antibiotic gives prophylaxis against wound infection in at-risk abdominal surgery which is at least as effective as multiple doses. However, there may be a risk of overwhelming systemic sepsis in very elderly patients having emergency surgery.

A randomised prospective controlled study of ciprofloxacin with metronidazole versus amoxicillin/clavulanic acid with metronidazole in the treatment of intra-abdominal infection

A prospective randomised study was undertaken in 80 patients to assess the combined regimen of ciprofloxacin with metronidazole against amoxicillin/clavulanic acid with metronidazole as treatment for established intra-abdominal infection. Treatment was for five days. Seventy-eight patients were clinically evaluable (38 patients on ciprofloxacin with metronidazole and 40 patients on amoxicillin/clavulanic acid with metronidazole). The overall clinical success rate in the treatment of intra-abdominal infections was 96% for the ciprofloxacin with metronidazole group, and 90% for the amoxicillin/clavulanic acid with metronidazole group. Over half of all patients were able to change from intravenous to oral antibiotic administration within the study period. One patient receiving ciprofloxacin with metronidazole developed pruritus near the injection site.

Combined topical and systemic antibiotic prophylaxis in acute appendicitis

Two hundred forty-six patients with acute appendicitis were randomly assigned to one of two groups. One group of 120 patients received systemic clindamycin preoperatively. Another group of 126 patients received, in addition to systemic clindamycin, a solution of topical ampicillin applied to subcutaneous tissues. No differences were found in the characteristics of the two groups. Combined prophylaxis with clindamycin and ampicillin significantly reduced wound infection to 4%, compared with clindamycin alone (p less than 0.02). A decrease in the surgical wound infection rate in the group treated with clindamycin and ampicillin was mainly observed in patients with advanced (gangrenous and perforated) appendicitis (p less than 0.05). A significant decrease in wound infection rates in patients with positive culture results was also found. We conclude that prophylaxis with a combination of systemic clindamycin and topical ampicillin solution, when compared with clindamycin alone, more effectively prevents wound infection after emergency appendectomy, especially in patients with serious wound contamination.

Antibiotic prophylaxis in acute nonperforated appendicitis. The Danish Multicenter Study Group III

In a prospective, block-randomized, multicenter study, the safety and efficacy of cefoxitin in preoperative prophylaxis were studied. 1735 patients undergoing appendectomy were evaluable, and half of these patients received 2 g of cefoxitin before undergoing operation. The patients were divided into three groups: patients with a normal appendix, patients with an acutely inflamed appendix, and patients with a gangrenous appendix. The study showed for each group a significant reduction of the incidence of wound infection in patients receiving prophylaxis. However, intra-abdominal abscess formation was not influenced by preoperative antibiotic prophylaxis. Consequently, routine preoperative prophylaxis is recommended before appendectomy.

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.

Metronidazole

Metronidazole is a highly effective therapy for anaerobic infections and a variety of protozoal and parasitic diseases. Its pharmacokinetics, toxicities, and unique mode of action are reviewed in detail. Indications for use and respective dosages are suggested.

Survey of antibiotic prophylaxis in gastrointestinal surgery in Scotland--5 years on

The results of a 5-year follow-up survey of the use of prophylactic antibiotics in gastrointestinal surgery in Scotland are reported. There have been significant increases in the routine use of prophylactic antibiotics during elective cholecystectomy (21% to 53% of surgeons; P less than 0.001) and appendicectomy (49% to 79% of surgeons; P less than 0.001). In addition a substantial number of surgeons used prophylactic antibiotics in selected high risk patients undergoing biliary tract surgery and gastroduodenal surgery.

Single-dose clavulanate-potentiated amoxycillin versus three-dose cefotaxime in the prevention of wound infection following elective cholecystectomy: a prospective randomized study

A prospective randomized study was carried out to evaluate the efficacy of clavulanate-potentiated amoxycillin with that of cefotaxime as prophylactic agents for the prevention of sepsis following elective cholecystectomy. One hundred patients were randomized into two treatment groups. In the first group, each patient received a single intravenous dose (1200 mg) of clavulanate-potentiated amoxycillin 2 h before surgery. In the second group, patients were given intravenous cefotaxime, in three doses (2 g each) during surgery, and 6 and 12 h after their operation. No case of serious post-operative sepsis occurred in either group. Superficial wound infection occurred in 2% of patients receiving a single pre-operative dose of clavulanate-potentiated amoxycillin and in 6% of those given cefotaxime according to the three-dose regimen.

Metronidazole prophylaxis in acute mural appendicitis: failure of a single intra-operative infusion to reduce wound infection

The efficacy of a single 500 mg intravenous intra-operative dose of metronidazole in the prevention of postoperative wound infection, following appendicectomy for acute mural appendicitis, was studied in a prospective randomized placebo controlled trial. Fourteen of the 96 patients (14.6%) in the metronidazole group and 13 of the 94 in the placebo group (13.8%) developed postoperative wound infection. Late sepsis was noted in 4 out of the 96 patients in the metronidazole group and in one of the 94 patients in the placebo group. This study suggests that a single intra-operative dose of metronidazole dose not reduce the incidence of postoperative wound infection following appendicectomy for acute mural appendicitis.