Severe Postoperative Infections Research Articles

Vascular Nosocomial Nocardia farcinica Infection After Arterial Stenting in an Immunocompetent Patient

Vascular Nosocomial <i>Nocardia farcinica</i> Infection After Arterial Stenting in an Immunocompetent Patient

Storage time of allogeneic red blood cells is associated with risk of severe postoperative infection after coronary artery bypass grafting☆

The storage time of allogeneic red blood cells (RBCs) has been linked with the risk of severe postoperative infections following cardiac surgery. However, existing data are sparse and inconsistent. We therefore examined the association between the age of transfused RBCs and development of severe postoperative infection following coronary artery bypass grafting (CABG) in a large population-based cohort study. The study included patients undergoing CABG with or without concomitant cardiac surgery between June 2003 and July 2008 in the North and Central Denmark regions. Data on demography, perioperative variables, allogeneic blood transfusion and severe postoperative infections (deep sternal wound infection, bacteremia or septicemia) were retrieved from medical databases and medical records. We used logistic regression analyses to compute the crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) for the association between storage time of transfused RBCs and the risk of severe infection. A total of 4240 patients were included in the final analyses, and 1748 of these patients (41%) were transfused with RBCs. Among transfused patients, 953 were exclusively transfused with RBC stored for < 14 days and 548 were exclusively transfused with RBC stored for ≥ 14 days. Severe infection was identified in 165 patients (3.9%). The adjusted ORs for severe infection among all transfused patients and patients transfused with RBCs stored exclusively for either < 14 days or ≥ 14 days were 1.6 (95% CI: 0.9-2.8), 1.1 (95% CI: 0.6-2.1), and 2.3 (95% CI: 1.2-4.2), respectively, when compared with non-transfused patients. There was a dose-response relationship between the number of transfused RBC units and the risk of severe infection among patients exclusively transfused with RBCs stored for ≥ 14 days. Although the risk of possible confounding could not be eliminated entirely in this observational study, the findings add further support for the hypothesis that storage time of RBCs is positively associated with the risk of transfusion-related severe postoperative infection in patients undergoing CABG.

Drug Susceptibility of Isolates from Severe Postoperative Intraperitoneal Infections Causing Multiple Organ Failure

To select the most appropriate antibiotic regimens for life-threatening postoperative infections, we obtained isolates from patients with severe postoperative infections over a 12-year-period, and examined their drug susceptibility. The subjects of this study were 55 patients with multiple organ failure (MOF) caused by postoperative infection. All strains of Methicillin-resistant Staphylococcus aureus (MRSA) were susceptible to Vancomycin (VCM) and Teicoplanin (TEIC). Only 0.3% of all the Pseudomonas aeruginosa strains were resistant to Imipenem (IPM), but 53.6% of the strains from the severe infections were resistant to IPM. On the other hand, there were few P. aeruginosa strains resistant to Meropenem (MEPM), Ceftazidime (CAZ), Ciprofloxacin (CPFX), and Pazufloxacin (PZFX), even among strains isolated from severe infections. The resistant rate of Bacteroides fragilis to Clindamycin (CLDM) was 35.9%, but there were strains resistant to IPM and Panipenem. These findings suggest that VCM or TEIC are most appropriate for severe abdominal abscess caused by MRSA, whereas MEPM, CAZ, CPFX, and PZFX are more effective against P. aeruginosa infections. The only antibiotic effective against B. fragilis infections in this study was IPM.

Informed consent is not routinely documented for procedures using allografts.

Patients who receive musculoskeletal allografts may have severe postoperative infections develop. Media reports have heightened public awareness of the risk of allograft use. Explaining these risks to patients preoperatively has become more important as attention to informed consent issues has increased. This study retrospectively investigated the patterns of informed consent for allograft bone used during elective orthopaedic procedures at a major teaching hospital. Forty-seven (32%) of 148 patients had preoperative discussions of allograft risks and benefits documented with a signed preoperative consent. In nearly 70% of the cases in which structural allograft was used, preoperative consent was documented. Only 8% of cases in which nonstructural, highly processed allograft was used had documented preoperative consent. Forty-eight (32%) of 148 patients were treated with allograft and autograft. Consent was obtained for the harvesting and use of autograft from 90% of these patients. In none of these patients was consent obtained for the allograft used. Although risks of disease transmission vary widely with the degree of allograft processing and the source of its procurement, informed consent for any allograft use should be a routine part of preoperative discussions of risks and benefits in elective orthopaedic surgeries.

Experience with ampicillin/sulbactam in severe infections.

The emergence of beta-lactamase-mediated resistance to established beta-lactam antibiotics prompted the development of beta-lactamase inhibitors for co-administration. Ampicillin has been combined with sulbactam for both parenteral and oral (as the mutual pro-drug sultamicillin) administration. The combination is active in vitro against a wide variety of Gram-positive and Gram-negative pathogens, including aerobic and anaerobic organisms. In clinical trials, ampicillin/sulbactam has proved clinically and bacteriologically effective against a variety of frequently encountered pediatric infections, including mild-to-moderate upper respiratory tract infections (acute otitis media, sinusitis, pharyngitis, and tonsillitis), severe post-operative and intra-abdominal infections, periorbital infections (which, left untreated, can lead to blindness, brain abscess, or death), acute epiglottitis, bacterial meningitis, and brain abscess. Ampicillin/sulbactam has also proved effective in the prevention of post-operative surgical infections in pediatric patients. The clinical efficacy profile of ampicillin/sulbactam and sultamicillin, combined with their excellent tolerability profile, make these agents attractive options for the management of many life-threatening infections in pediatric patients.

Clinical value of soluble interleukin-2 receptor in infectious complications.

In this study, we investigated serum-soluble interleukin-2 receptor (sIL-2r) and neopterin (NPT) levels in five patients with severe postoperative infections. A total of 25 synchronous determinations of sIL-2r and NPT were performed. A marked increase in sIL-2r and NPT levels was observed, and the increase in sIL-2r was significantly correlated to that of NPT which is a marker of macrophage activity. These results suggest that macrophages are involved in the stimulation of sIL-2r release, representing a potentially negative biological effect. The results indicate that sIL-2r may be a useful indicator of the efficacy of antibiotics and of prognosis.

A new method for the quantification of β-glucan in plasma and its application in the diagnosis of postoperative infection

In order to correctly diagnose and treat severe postoperative infections, it may be critical to detect and differentiate between endotoxin derived from Gram-negative bacteria and/or beta-glucan derived from fungi. In addition to the chromogenic assay, the turbidimetric kinetic assay has been performed for the quantification of endotoxin in plasma using Limulus amebocyte lysate as previously reported. However, it is also known that beta-glucan triggers the coagulation of Limulus amebocyte lysate. In the present study, the differentiation of beta-glucan from endotoxin and its clinical application were studied. Endotoxin was able to be inactivated in plasma using one-tenth dilution by 10 per cent ethanol or distilled water, followed by heating at 100 degrees C for 120 min, without affecting the activity of coexisting beta-glucan. The treated sample was then subjected to the turbidimetric kinetic assay using Toxinometer ET-201. Using this method, as little as 30 pg/ml of beta-glucan in the plasma may be assayed separately, with the amount of circulating beta-glucan in the plasma of normal subjects being less than 50 pg/ml. On the other hand, in patients with a fungal infection, the amount of beta-glucan in their plasma was elevated significantly. Clinically, beta-glucanemia may often occur in severe postoperative infection even if fungi are not detected.

L-carnitine enhances lymphocyte mitogenesis in depleted traumatised and infected patients

The influence of L-carnitine on concanavalin (ConA)-induced lymphocyte mitogenesis in vitro was studied in six depleted patients with severe post-operative infections and in eight healthy control subjects. Three patients had received i. v. carnitine supplementation as part of a clinical trial. One patient was studied both before and after i.v. carnitine supplementation. Five patients showed a poor or absent mitogen response compared with the controls. Carnitine markedly augmented the mitogen response in all these patients. In the patient studied before and after i. v. carnitine supplementation, the low initial ConA response increased to values seen in normal individuals. In the lymphocytes from healthy control subjects, no effect of carnitine on activation could be observed. The results demonstrate a stimulatory effect of L-carnitine on lymphocyte mitogenesis in depleted patients with severe post-operative infections.

Perioperative Infection Prophylaxis in Vascular Surgery - A Randomized Prospective Study

In 300 reconstructive arterial operations of the abdominal aorta and the lower limbs, a randomized prospective study of the effect of perioperative infection prophylaxis with antibiotics was performed. The evaluation was carried out with regard to the frequency of severe postoperative wound infections. As prophylactic antibiotic Cefuroxime was initially used, Cefotaxim was later administered. Cefotaxim has been proven to be the appropriate antibiotic against the special microbial spectrum of our clinic. Side effects or complications due to the antibiotics were not found. Wound infections of all grades of seriousness occurred in the group without infection prophylaxis in 15.1%, in the antibiotic group in 3% (p less than 0.001). Serious wound infection endangering or involving the transplant were found in the group without prophylaxis in 7.2%, whereas in the antibiotic group in 1.5%. Infections of the vascular prosthesis were observed in 2.4% and 0.8% respectively. Most wound infections occurred in the groin. The most common infecting organisms were Staphylococcus aureus or epidermidis. A higher risk of wound infections due to old age or gangrene could not be observed. Although wound infections in peripheral vascular surgery are relatively rare, they have severe consequences. It is therefore advisable to administer perioperative infection prophylaxis which significantly reduces this complication, especially in patients with synthetic implants.

Menstrual Regulation as a Method for Early Termination of Pregnancy

116 women with documented or suspected pregnancy underwent an endometrial aspiration for early termination. Their menses delay was between 7 and 22 days. A standard 3 mm Vabra aspirator was used. 90.5% were actually pregnant. The success rate was 97.1%. The total complication rate was 6.8%, the most common complication being endometritis. Three patients required a re-evacuation because of prolonged bleeding. In this series there were two ectopic pregnancies and nine cases of ovum abortivum, of which one later turned out to be a hydatiform mole. The procedure was well tolerated by the patients. No sick-leave was given. The postoperative bleeding averaged 10 days in primigravid and 7 days in parous patients.

Overwhelming postoperative streptococcal infection

Fulminant postoperative group A beta-hemolytic streptococcal infections present a serious and potentially lethal threat to children. Three children with severe postoperative streptococcal wound infections are presented. Each child developed high fever within the first 24 hr after surgery, followed shortly by signs of septic shock. In all patients, the clinical appreciation of wound infection became apparent late in the course of the illness. All three children had white blood cell counts below 6000/cu mm. One child developed crepitus in the incision; another showed radiographic evidence of free air in the soft tissues. The only survivor received antibiotics immediately following the initial fever along with re-exploration and drainage of the operative wound.

Sternal Osteomyelitis and Mediastinitis after Open-Heart Operation: Pathogenesis and Prevention

Sternal osteomyelitis and mediastinitis caused by Pseudomonas cepacia developed in a patient undergoing coronary artery bypass two weeks after the operation. P. cepacia bacteremia from a contaminated pressure transducer had preceded and probably caused the chest infection. While other authors have suggested that postoperative sternal osteomyelitis and mediastinitis result from local wound contamination, this case suggests the importance of bacteremia as a cause of such gram-negative infections. Since patients undergoing open-heart operation are exposed to many sources of bacteremia, prevention of severe postoperative chest infections may depend in large part on careful preoperative evaluation of each patient for occult infections, on judicious selection of prophylactic antibiotic regimens, and, as shown in this patient, on very thorough periodic review of equipment sterilization and intravascular monitoring practices.

POST-SPLENECTOMY INFECTION IN INFANTS AND CHILDREN

Fatal or life-threatening infection occurred in 13 members of a post-splenectomy population of 110 individuals followed for a median period of 6 years. Division of the population into two groups, one group predisposed to infection by the basic disease and/or the treatment which led to splenectomy and another non-predisposed group, revealed a distinct difference in the hazard. The non-predisposed group of 63 individuals had only one severe infection; this experience does not suggest risk of a very high order. Our Experience combined with that of others reporting cases in this category, provides a total splenectomy population of 205 with but two severe infections. It is evident that splenectomy carries a very low risk of post-operative infection when done over the age of 6 months for the generally accepted indications of splenic rupture, congenital spherocytic anemia, and idiopathic thrombocytopenic purpura. In the 47 individuals in this study predisposed to infection by their underlying disease, the incidence of severe post-operative infection was approximately 25%. No relation to age at time of splenectomy was evident. Ten of the 12 infections occurred within 12 years of operation. No attempt has been made to assess how great an increase, if any, this represents over a non-splenectomized control population similarly predisposed to infection. Our Experience, in addition to that of others, in the group predisposed to infection by their underlying disease, makes a total splenectomy population of 85; 23 (27%) of this group suffered severe post-operative infections.