The Characteristics of Postoperative Mediastinitis During the Changing Phases of Cardiac Surgery.

BACKGROUND: Mediastinitis is a serious complication of open heart surgery associated with high mortality, considerable health care costs, and prolonged hospital stay. We examined characteristics and incidence of mediastinitis during 29 years when indications and patient material have been in a process of change. METHODS: This was a retrospective population-based study comprising all mediastinitis patients more than 16 years of age after open heart surgery between 1990 and 2018 from a population of 1.7 million. Patient records of 50 mediastinitis patients from 2004 to 2014 were reviewed and compared with 120 patients from 1990 to 1999. RESULTS: Annual mediastinitis rate varied 0% to 1.5% with a decreasing trend-from a level exceeding 1.2% to approximately 0.3%-over the study period. In 2004 to 2014 patients with mediastinitis were older, more often smokers, and more often had diabetes mellitus and renal insufficiency than in 1990 to 1999. No difference in length of hospital treatment, antibiotic prophylaxis or treatment, intensive care unit treatment, or mortality was observed between 1990 to 1999 and 2004 to 2014. Coronary artery bypass graft surgery became less common and valve replacement and hybrid operations more common among operations leading to mediastinitis. Staphylococcus aureus increased (from 25% to 56%, p = .005) whereas coagulase-negative staphylococci (46% to 23%, P < .001) and gram-negative bacteria (18% to 12%, P = .033) decreased as causative agents. Surgery for mediastinitis remained similar except introduction of vacuum-assisted closure treatment. CONCLUSIONS: The rate of mediastinitis decreased during these 29 years. No difference in 30-day mortality in mediastinitis was seen: 0.9% in 1990 to 1999 and 2% in 2004 to 2014.

Prevention of sternal wound infections with locally administered gentamicin.

Despite modern surgical techniques and our knowledge of the pathogenesis of surgical site infections (SSIs) and the use of perioperative antibiotic prophylaxis, the incidence of SSIs has not decreased, but has remained at the same level. More effective preventive methods are thus needed and will likely become even more important in the future due to older and sicker patients, the population becoming increasingly obese, type II diabetes becoming more common, and the emergence of resistant bacteria. The use of local antimicrobial prophylaxis was studied. The study population comprised 557 patients who underwent elective CABG. The patients were randomized and patients in the study group received a 10 cm x 10 cm gentamicin-collagen implant. Postoperative SSI occurred in 11 of 272 patients (4.0%) in the study group and in 16 of 270 patients (5.9%) in the control group. This difference was not statistically significant (P=0.20). There were three cases of mediastinitis (1.1%) in the study group and five (1.9%) in the control group (P=0.47).

Mediastinitis after more than 10,000 cardiac surgical procedures.

BACKGROUND: Poststernotomy mediastinitis as a complication is rare but disastrous. We assessed incidence, predisposing factors for, and outcome from, mediastinitis after cardiac surgery. METHODS: We studied 10,713 consecutive patients who underwent open-heart surgery from 1990 to 1999 in a tertiary care university hospital using data prospectively recorded in the hospital discharge register, operating room log, and the hospital's cardiothoracic surgery unit register. Those cases with possible mediastinitis were identified from the hospital infection register and discharge register. Patients' charts were reviewed and cases of mediastinitis confirmed based on criteria of the Centers for Disease Control and Prevention. RESULTS: The overall rate of mediastinitis was 1.1% (120 cases), and higher in coronary artery bypass surgery than in valvular surgery (1.2 vs 0.8%). No trend in incidence was detectable, although surgical patients became progressively older (mean age, 59 to 65 years, p < 0.01), and the proportion of women (from 25% to 31%; p < 0.01) and of patients with American Society of Anesthesiologists score over 3 (from 10% to 81%, p < 0.01) both increased. The rate of mediastinitis was almost twice as high in men (1.2% vs 0.7%, p < 0.01). In three body mass index (BMI) categories (<25, 25 to 30, and >30 kg/m2), rates of mediastinitis were 0.5%, 1.0%, and 1.8%. In multivariate analysis adjusted for age, sex, year, operation type, and perfusion time, the only predictor for mediastinitis was BMI. CONCLUSIONS: Mediastinitis is not diminishing. Larger populations at risk, for example proportions of overweight patients, reinforce the importance of surveillance and pose a challenge in focusing preventive measures.

Glove punctures and postoperative skin flora of hands in cardiac surgery.

BACKGROUND: Surgical gloves are frequently perforated during operations, including heart operations. This infection risk factor is inadequately studied. METHODS: After preoperative hand disinfection and at the end of 116 heart operations, bacterial samples from hands of surgeons, altogether 800 samples, were taken. Glove punctures were examined with water test. RESULTS: Surgeons changed 70 gloves because of breakage during operations. Additionally, 154 of 400 (39%) gloves had holes in postoperative testing. The breakage rate of gloves increased from 30% in operations shorter than 3 hours to 65% when operations were longer than 5 hours. High bacterial counts of the hands were also more common after prolonged operations. CONCLUSIONS: Glove puncture rates and bacterial counts of hands increase with increasing operation time. We recommend changing of both gloves when a puncture is detected. Before donning new gloves, hands should be disinfected.