A comparison of the penetration of two quinolones into intra-abdominal abscess.

A low-mortality model of an intra-abdominal abscess in the rat has been used to study the penetration of two quinolone agents into pus. Maximum concentrations in pus after intravenous injections were achieved at four hours (ciprofloxacin: 12.7 +/- 3.69 mg/L, fleroxacin: 2.25 +/- 1.82 mg/L), whereas fleroxacin given orally reached the maximum level at two hours (13.39 +/- 3.13 mg/L). Higher concentrations of fleroxacin were recorded in pus than in serum at each time point up to eight hours after administration, but pus levels of ciprofloxacin only exceeded serum levels after 1.5 hours. These antibiotics appear to have a unique property of high penetration into established abscesses and may have an important therapeutic role in the treatment of patients with multiple interloop abscesses.

New advances in antibiotic prophylaxis for colorectal surgery.

The major advances in antibiotic prophylaxis in colorectal surgery have come from an awareness of the need for appropriate agents against the known likely pathogens and from knowledge of the pharmacokinetics of these drugs. Intensive study has been undertaken to identify optimal regimens, but as there is great variability in the settings under which these operations take place, it is not always possible to compare the results of these various investigations. There is little doubt that in many cases there is gross contamination with faecal organisms and the term prophylaxis is inappropriate so that prolonged courses of antibiotics would appear to be safer. However, work towards identifying patients at increased susceptibility of developing septic complications may well further improve the outcome of colorectal surgery.

The umbilical and paraumbilical veins of man.

During its transit through the umbilicus structural changes occur in the thick wall of the extra-abdominal segment of the umbilical vein whereby the components of the intra-abdominal segment acquire an essentially longitudinal direction and become arranged in fibro-elastic and fibro-muscular zones. The vein lumen becomes largely obliterated by asymmetrical proliferation of loose subendothelial conective tissue. The latter forms a new inner zone within which a small segment of the lumen persists in an eccentric position. This residual lumen transmits blood to the portal system from paraumbilical and systemic sources, and is retained in the upper part of the vein, even in old age. A similar process of lumen closure is observed in the ductus venosus. In early childhood the lower third of the vein undergoes breakdown, with fatty infiltration, resulting in its complete division into vascular fibro-elastic strands, and in old age some breakdown occurs in the outermost part of the wall of the upper two thirds. The paraumbilical veins are thick-walled and of similar structure to the umbilical vein. Together they constitute an accessory portal system which is confined between the layers of the falciform ligament and is in communication with the veins of the ventral abdominal wall. The constituents form an ascending series, namely, Burow's veins, the umbilical vein, and Sappey's inferior and superior veins. The main channel of Sappey's inferior veins may be the remnant of the right umbilical vein since it communicates with the right rectus sheath and often communicates directly with the portal system within the right lobe of the liver. The results are of significance in relation to clinical usage of the umbilical vein.

The management of inflammatory complications of colonic diverticular disease.

Inflammatory complications of colonic diverticular disease remain a common and dangerous cause for hospital admission in our ageing society. The presentation, pathology, general and surgical management of acute diverticulitis, peritonitis and perforation of colonic diverticular disease are reviewed.

National audit of complicated diverticular disease: analysis of index cases.

Details of 300 patients with complicated diverticular disease from 30 hospitals between 1985 and 1988 were entered into a national audit organized by the Surgical Research Society. Complications present on admission included acute phlegmon (n = 104), pericolic abscess (n = 34), purulent peritonitis (n = 40), large bowel obstruction (n = 31), faecal peritonitis (n = 23), pericolic abscess complicated by fistula (n = 28) and lower gastrointestinal bleeding (n = 40). The overall mortality rate was 11.3 per cent (acute phlegmon, 4 per cent; purulent peritonitis, 27 per cent; pericolic abscess, 12 per cent; faecal peritonitis, 48 per cent; large bowel obstruction, 6 per cent; bleeding, 2 per cent; fistula, 4 per cent). Acute phlegmon was treated without operation in 78 patients (75.0 per cent) and by resection in 24 (23.1 per cent). Management of purulent peritonitis generally involved Hartmann's procedure (62 per cent) or resection and primary anastomosis (15 per cent). Similarly, patients with pericolic abscess usually underwent Hartmann's procedure (38 per cent) or resection and primary anastomosis (35 per cent). The principal operation for faecal peritonitis was Hartmann's resection (83 per cent). Large bowel obstruction was managed conservatively in four patients (13 per cent), by Hartmann's procedure in nine (29 per cent), and by resection and primary anastomosis with or without a proximal stoma in 13 (42 per cent). Most patients (82 per cent) with fistula associated with an abscess were managed by resection and primary anastomosis; 90 per cent with acute gastrointestinal bleeding were treated without operation.

The 5-year natural history of complicated diverticular disease.

The natural history of complicated diverticular disease based on details of 300 patients entered into a national audit between 1985 and 1988 is reported. Questionnaires were sent to the general practitioners of 176 patients with this condition 5 years after hospital admission; 120 responded. Of these 120 patients, ten died from recurrent complicated diverticular disease, 29 died from other disorders and 81 remain alive. Forty of 110 patients (excluding those who died from recurrence) are still symptomatic or were so at the time of unrelated death. Thirty-nine patients developed a severe complication after the index admission, 14 of whom had the same complication initially. Of the 77 patients who had initially been managed by sigmoid resection, only two developed recurrent complications compared with 37 of 43 managed conservatively. Of the ten patients who died from recurrent diverticular disease, nine had not undergone sigmoid colectomy at or after the original admission. These data argue for interval sigmoid colectomy in most patients who initially present to hospital with complicated diverticular disease to prevent later development of potentially lethal complications.

The penetration of fleroxacin into intra-abdominal abscesses.

Using a recently developed, low mortality model of an intra-abdominal abscess in the Wistar rat, we have studied the penetration of fleroxacin into the abscess. Maximum serum concentration was 1.83 +/- 0.39 mg l and occurred 1 h after iv injection (20 mg/kg), but even at 4 h after administration the mean serum level was 1.21 +/- 0.27 mg/l. By contrast, levels in pus were 6.27 +/- 0.83 mg/l at 1 h rising steadily to a value of 12.7 +/- 3.69 mg/l at 4 h. The study has confirmed exceptional antibiotic penetration into the abscess, with levels at all time intervals between 0.5 and 8 h after administration in excess of the MIC50 for Escherichia coli, Proteus vulgaris and Clostridium perfringens.

Comparison of short-term antibiotic cover with a third-generation cephalosporin against conventional five-day therapy using metronidazole with an aminoglycoside in emergency and complicated colorectal surgery.

In a prospective, randomized control trial, 152 consecutive patients requiring emergency or complicated colorectal surgery were allocated either to two doses of cefotetan or to five-day cover with gentamicin, and a single dose of metronidazole. Twenty-one patients received 6 gm of cefotetan before prolongation of prothrombin time dictated a change in the dose regimen such that all remaining patients (N = 55) received only 4 gm of cefotetan. The groups were well matched for diagnosis and surgical procedure. Rates of postoperative infection did not differ significantly between the groups, with wound infection rates occurring in 17 of 75 patients receiving gentamicin and metronidazole (22.7 percent) compared with ten of 75 receiving cefotetan (13 percent). Although wound infection rates were lower in the cefotetan group, the incidence of intra-abdominal abscess was similar in both groups. Eight patients receiving cefotetan developed intra-abdominal abscesses (11 percent), compared with seven receiving gentamicin and metronidazole (9 percent). Prolongation of prothrombin time in excess of 13 seconds occurred in six patients receiving cefotetan compared with no patients receiving gentamicin and metronidazole. None of these patients developed clinical bleeding, however.