Chlorhexidine lavage in the treatment of experimental intra-abdominal infection

HYPOTHESIS

Closed postoperative peritoneal lavage (CPPL) with chlorhexidine gluconate reduces the number of intraperitoneal bacteria and improves the outcome of intra-abdominal infection.

DESIGN

Laboratory animal trial.

INTERVENTIONS

Intra-abdominal infection was produced in mice by the cecal ligation and puncture technique. After 16 to 18 hours, the animals underwent relaparotomy and placement of an intra-abdominal catheter for CPPL. In the first experiment animals were randomly divided into 4 groups: no lavage (served as a control), CPPL with chlorhexidine. CPPL with cefoxitin, and CPPL with lactated Ringer solution (LR). Lavage was continued intermittently every 8 hours for 24 hours. All animals received systemic cefoxitin every 8 hours for 7 days. Mortality was recorded every 8 hours for 10 days. In the second experiment, animals were divided into 3 groups: no lavage (served as a control), CPPL with chlorhexidine, and CPPL with LR. Lavage was continued intermittently every 8 hours for 24 hours. The animals were killed 48 hours after reoperation. Bacterial counts from peritoneal fluid and biopsy specimens, as well as peritoneal white blood cell counts, were measured before and after lavage.

RESULTS

Closed postoperative peritoncal lavage with chlorhexidine reduced mortality from 71% in a control group to 37% (P = .003). There was no survival benefit in either the CPPL with cefoxitin (91% mortality) (P = .14) or CPPL with LR groups (90% mortality) (P = .17). The statistically significant findings of analysis of variance evaluation demonstrated a decrease in bacterial counts after cecal excision in all 3 groups. There was a greater reduction in bacterial counts in the chlorhexidine group compared with the control group (P<.05). Bacterial counts decreased in peritoneal fluid, as well as in tissue biopsy specimens, after cecal excision. White blood cell counts significantly decreased after cecal excision in all 3 groups. There was no difference in white blood cell counts between the groups. Correlation analyses demonstrated weak interaction between bacterial and white blood cell counts before or after treatment in all the groups. Pearson r ranged from -0.37 to +0.35, none of which were statistically significant.

CONCLUSIONS

In our experiments chlorhexidine lavage resulted in a 50% reduction in mortality and a significant reduction in bacterial counts compared with the control group. There was no survival benefit from lavage with either cefoxitin or LR. There was no reduction in bacterial counts in the LR group relative to the control group. Thus, the survival benefit and the reduction in bacterial numbers are attributed to the antibacterial properties of chlorhexidine rather than to the mechanical washing of the abdominal cavity. Closed postoperative peritoneal lavage with 0.05% chlorhexidine gluconate might be useful in the multimodal treatment of intra-abdominal infection.

Needle-localized breast biopsy for mammographic abnormalities: a community hospital experience

Increased awareness of benefits of early detection of breast cancer has resulted in increased numbers of screening mammographies and breast biopsies for nonpalpable lesions. Tertiary hospital studies have demonstrated positive biopsy rates from abnormal mammographic findings at 18 to 32 per cent. We examined the effectiveness of needle biopsy for nonpalpable radiographic abnormalities in our community hospital. We reviewed 167 records of patients biopsied over a 2-year period. Mammographic assessment, biopsy, and pathological assessment were performed using accepted methods. Malignancy was detected in 34 of 167 biopsies (20%). The biopsy yield rate was highest for mammographic findings of spiculated or stellate masses (75%, P < 0.01). Most biopsies (83%) were performed because of mammographic findings of microcalcifications or circumscribed enlarging masses/nodular developing densities for a positive biopsy yield rate of 16 per cent. Rates were higher in patients with personal (44%) or family history (30%) of breast cancer and in postmenopausal women (30%). These results demonstrate that 1) factors such as age, personal or family history of breast cancer, and certain mammographic features of breast lesions are associated with high biopsy yield rates, and 2) the biopsy yield rate in our community setting is comparable to tertiary hospital experience.

Iliopsoas abscess: etiology, diagnosis, and treatment

Iliopsoas abscess is a rarely encountered entity. Early diagnosis is hindered by a nonspecific clinical presentation. The resulting delays in therapy increase morbidity and mortality rates. Our recent experience with three cases of iliopsoas abscess is presented. Based on a review of the literature, diagnostic and treatment recommendations are made.

Surgical treatment of Meckel's diverticulum

Meckel's diverticula are the result of incomplete degeneration of the vitelline duct. It is generally believed that less than 5% of them become symptomatic, the frequency decreasing with age. Meckel's diverticula are most commonly manifested in children by painless lower gastrointestinal bleeding and in adults, as an inflammatory process or obstruction. Definitive diagnosis is usually made at surgery, though the Meckel's scan may suggest a diagnosis preoperatively, especially in the pediatric population. All symptomatic and pathologic Meckel's diverticula should be removed with a segment of ileum. The use of stapling devices, with their ease of use and low complication rate, make it reasonable to remove any Meckel's diverticulum that easily fits in the device. If a diverticulum found incidentally is so broad-based or short that stapling cannot be done without difficulty, it is unlikely to become symptomatic and should be left undisturbed.

Abdominal and anorectal surgery and the acquired immune deficiency syndrome in heterosexual intravenous drug users

Over a period of seven years, 474 patients with acquired immune deficiency syndrome (AIDS) or AIDS-related complex were admitted on 782 occasions to the St. Francis Medical Center, Trenton, New Jersey. Abdominal surgery was performed on 16 (3.4 percent) patients, 14 (88 percent) of whom were heterosexual intravenous drug users. Anorectal surgery was performed on 20 (4.2 percent), 14 (70 percent) of whom were intravenous drug users. Intravenous drug users undergoing abdominal surgery had the same types of surgical abdominal conditions that occur in the general population. None required surgery for complications secondary to cytomegalovirus, visceral lymphoma, or visceral Kaposi's sarcoma. The postoperative morbidity rate was 72 percent. The postoperative mortality rate (30 day) was 0 percent. No intravenous drug users who underwent anorectal surgery had associated anorectal malignancies or infectious diseases. Five of six homosexual patients had either an anorectal malignancy or an associated anorectal infectious disease. Anorectal wounds did not heal within one month in one third of the intravenous drug users. The rate of wound healing was inversely related to the white blood cell count. One third of the intravenous drug users undergoing anorectal surgery were dead within six months.