Continuous wound infiltration versus epidural analgesia for midline abdominal incisions - a randomized-controlled pilot trial (Painless-Pilot trial; DRKS Number: DRKS00008023).

OBJECTIVES: To test the feasibility of a randomized controlled study design comparing epidural analgesia (EDA) with continuous wound infiltration (CWI) in respect to postoperative complications and mobility to design a future multicentre randomized controlled trial. DESIGN, SETTING, PARTICIPANTS: CWI has been developed to address drawbacks of EDA. Previous studies have established the equivalent analgesic potential of CWI compared to EDA. This is a single centre, non-blinded pilot randomized controlled trial at a tertiary surgical centre. Patients undergoing elective non-colorectal surgery via a midline laparotomy were randomized to EDA or CWI. Endpoints included recruitment, feasibility of assessing postoperative mobility with a pedometer and morbidity. No primary endpoint was defined and all analyses were explorative. INTERVENTIONS: CWI with local anaesthetics (experimental group) vs. thoracic EDA (control). RESULTS: Of 846 patients screened within 14 months, 71 were randomized and 62 (31 per group) included in the intention-to-treat analysis. Mobility was assessed in 44 of 62 patients and revealed no differences within the first 3 postoperative days. Overall morbidity did not differ between the two groups (measured via the comprehensive complication index). Median pain scores at rest were comparable between the two groups, while EDA was superior in pain treatment during movement on the first, but not on the second and third postoperative day. Duration of preoperative induction of anaesthesia was shorter with CWI than with EDA. Of 17 serious adverse events, 3 were potentially related to EDA, while none was related to CWI. CONCLUSION: This trial confirmed the feasibility of a randomized trial design to compare CWI and EDA regarding morbidity. Improvements in the education and training of team members are necessary to improve recruitment. TRIAL REGISTRATION: DRKS00008023.

Modeling Acinetobacter baumannii wound infections: The critical role of iron.

BACKGROUND: Acinetobacter baumannii has emerged as an increasingly important and successful opportunistic human pathogen due to its ability to withstand harsh environmental conditions, its characteristic virulence factors, and quick adaptability to stress. METHODS: We developed a clinically relevant murine model of A. baumannii traumatic wound infection to determine the effect of local wound environment on A. baumannii virulence. Mice underwent rectus muscle crush injury combined with ischemia created by epigastric vessel ligation, followed by A. baumannii inoculation. Reiterative experiments were performed using (1) a mutant deficient in the production of the siderophore acinetobactin, or (2) iron supplementation of the wound milieu. Mice were euthanized 7 days later, and rectus muscle analyzed for signs of clinical infection, HIF1α accumulation, bacterial abundance, and colony morphotype. To determine the effect of wound milieu on bacterial virulence, Galleria mellonella infection model was used. RESULTS: The combination of rectus muscle injury with ischemia and A. baumannii inoculation resulted in 100% incidence of clinical wound infection that was significantly higher compared with other groups (n = 15/group, p < 0.0001). The highest level of wound infection was accompanied by the highest level of A. baumannii colonization (p < 0.0001) and the highest degree of HIF1α accumulation (p < 0.05). A. baumannii strains isolated from injured/ischemic muscle with clinical infection displayed a rough morphotype and a higher degree of virulence as judged by G. mellonella killing assay as compared with smooth morphotype colonies isolated from injured muscle without clinical infection (100% vs. 60%, n = 30 Log-Rank test, p = 0.0422). Iron supplementation prevented wound infection (n = 30, p < 0.0001) and decreased HIF1α (p = 0.039643). Similar results of decrease in wound infection and HIF1α were obtained when A. baumannii wild type was replaced with its derivative mutant [INCREMENT]BasD deficient in acinetobactin production. CONCLUSION: The ability of A. baumannii to cause infections in traumatized wound relies on its ability to scavenge iron and can be prevented by iron supplementation to the wound milieu.

Maintained deep brain stimulation for severe dystonia despite infection by using externalized electrodes and an extracorporeal pulse generator.

Infection in the context of implant surgery is a dreaded complication, usually necessitating the removal of all affected hardware. Severe dystonia is a debilitating condition that can present as an emergency and can occasionally be life threatening. The authors present 2 cases of severe dystonia in which deep brain stimulation was maintained despite the presence of infection, using ongoing stimulation by externalization of electrode wires and an extracorporeal pulse generator. This allowed the infection to clear and wounds to heal while maintaining stimulation. This strategy is similar to that used in the management of infected cardiac pacemakers. The authors suggest that this prolonged extracorporeal stimulation should be considered by neurosurgeons in the face of this difficult clinical situation.

Multiple organ injuries after abdominal high energy wounding in animals and the protective effect of antioxidants.

Multiple organ injuries caused by high energy abdominal wounds were studied in 8 pigs and 24 dogs, and at the same time the protective effect of antioxidants in 14 dogs with multiple organ injuries was also studied. The experimental results showed that: 1) more than two organs (six organs at most) were wounded in each of the animals studied; 2) the injuries were characterized by hemorrhaging, tissue rupture and hematoma, and the main pathologic changes were local edema and necrosis; 3) the marked increase of lipid peroxide (LPO) levels in the vital organs indicated that multiple organ injuries could also involve the molecular level; 4) the injuries were due to the direct effect of pressure waves and ischemic reperfusion and not to shock or infection; and 5) antioxidants (vitamin E and Salvia miltiorrhiza Bge.) exhibited significant protective effects against multiple organ injuries through a free radical mechanism.

Presumptive antibiotics for penetrating abdominal wounds.

The optimal antimicrobial agent or agents for penetrating abdominal injuries remains undetermined. During the three year period ending August 1987, 317 consecutive patients undergoing celiotomy for penetrating abdominal trauma were prospectively randomized to receive either mezlocillin, 4 grams every six hours, or clindamycin, 600 milligrams every six hours, and gentamicin, loading dose of 2.0 milligrams per kilogram, then 1.5 kilograms every eight hours. Antibiotics were begun in the emergency department with duration of coverage based on the pattern of injury: the colon, five days; other hollow visceral injury, two days, and all others, one day. Twenty-three patients were excluded because of breach of protocol and 16 others died within 72 hours of presentation. The two study groups, 136 patients receiving mezlocillin and 142 patients receiving gentamicin and clindamycin, were comparable with respect to age, sex, mechanism of injury, shock, intraoperative replacement of blood, abdominal trauma index and distribution of hollow visceral injuries. The over-all incidence of septic morbidity was similar: infections developed in 21 (15 per cent) of the patients receiving mezlocillin compared with 19 (13 per cent) of patients receiving gentamicin and clindamycin. There was no significant difference in major infections (lobar pneumonia and intra-abdominal abscess), with 13 per cent in each group. The offending pathogens were similar. The most common isolates in intra-abdominal abscess were Escherichia coli, Klebsiella and Enterococcus species and anaerobic Bacteroides species. Mezlocillin, an extended spectrum penicillin, achieved similar results, compared with the expensive and potentially toxic combination regimen in patients with penetrating abdominal injuries.

Presumptive antibiotics for penetrating abdominal wounds.

The optimal antibiotic agent or agents for penetrating abdominal injuries remains undetermined. During the two year period ending April 1985, 150 consecutive patients undergoing celiotomy for penetrating abdominal trauma were prospectively randomized to receive either mezlocillin (4 grams every six hours) or clindamycin (600 milligrams every six hours) and gentamicin (loading dose of 2.0 milligrams per kilogram, then 1.5 milligrams per kilogram every eight hours). Antibiotics were begun in the emergency department with duration of coverage based upon the injury pattern--colon, five days; other hollow visceral injury, two days, and all others, one day. Ten patients were excluded due to breach in protocol and other patients died within 48 hours of presentation. The two study groups, comprised of the remaining 130 patients, were comparable with respect to age, sex, injury mechanism, incidence of colonic injuries, intraoperative blood replacement and abdominal trauma index. Overall incidence of septic morbidity was similar among the groups; ten of the 61 patients receiving mezlocillin and nine of those receiving clindamycin and gentamicin had infection develop. There was no significant difference with respect to extensive abdominal infection (10 versus 3 per cent). The pattern of postoperative infection and offending pathogens were similar in the study groups. Enterobacteriaceae, enterococcus and Bacteroides species were most frequently isolated. Infection was due to an organism resistant to the initial study regimen in one of the ten failures with mezlocillin and in two of the nine failures with clindamycin and gentamicin. Mezlocillin, a single agent broad spectrum penicillin, achieved comparable results with more expensive potentially toxic combination therapy for penetrating wounds.