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.

Factors associated with blood culture positivity in patients with complicated skin and skin structure infection-a population-based study.

Skin and skin structure infection (SSSI) is classified as complicated (cSSSI) if it involves deep subcutaneous tissue or requires surgery. Factors associated with blood culture sampling and bacteremia have not been established in patients with cSSSI. Moreover, the benefit of information acquired from positive blood culture is unknown. The aim of this study was to address these important issues. In this retrospective population-based study from two Nordic cities, a total of 460 patients with cSSSI were included. Blood cultures were drawn from 258 (56.1%) patients and they were positive in 61 (23.6%) of them. Factors found to be associated with more blood culture sampling in multivariate analysis were diabetes, duration of symptoms shorter than 2 days and higher C-reactive protein (CRP) level. Whereas factors associated with less frequent blood culture sampling were peripheral vascular disease and a surgical wound infection. In patients from whom blood cultures were taken, alcohol abuse was the only factor associated with culture positivity, as CRP level was not. Patients with a positive blood culture had antibiotic streamlining more often than non-bacteremic patients. A high rate of blood culture positivity in patients with cSSSI was observed. Factors related to more frequent blood culture sampling were different from those associated with a positive culture.

A potential benefit from infectious disease specialist and stationary ward in rational antibiotic therapy of complicated skin and skin structure infections.

BACKGROUND: Management practices of complicated skin and skin structure infections (cSSSI) were compared between two areas with similar healthcare structure and low prevalence of antimicrobial resistance. METHODS: The high affinity to public health-care in the Nordic countries enabled population-based approach used in this retrospective study. The study population (n = 460) consisted of all adult residents from Helsinki (Finland) and Gothenburg (Sweden) treated in hospital due to cSSSI during 2008-2011. RESULTS: The majority of patients in Helsinki (57%) visited more than one ward during their hospital stay while in Gothenburg the majority of patients (85%) were treated in one ward only. Background and disease characteristics were largely similar in both cities but patients in Helsinki were younger [mean(SD) 59(18) versus 63(19) years, p = .0117], and greater proportions had diabetes (50% versus 32%, p < .0001) and polymicrobial infections (34% versus 13%, p < .0001). Patients in Helsinki received antimicrobials with Gram-negative coverage (in initial therapy 96%) more frequently than in Gothenburg (47%, p < .0001), had more treatment modifications (mean 4.3 versus 2.7 antibiotic agents used per patient, p < .0001), and longer median duration of antimicrobial therapy (29 versus 12 days, p < .0001) and median length of hospital stay (17 versus 11 days, p < .0001). CONCLUSIONS: This real-life study revealed remarkable differences in the management of cSSSI between the two Nordic cities. Compared to mainly Infectious Disease Specialist guided treatment in Gothenburg, the more frequent transfer from one ward to another in Helsinki was linked to longer antimicrobial therapy and hospital stay and to more frequent changes in antimicrobial treatment.

Microbiological Etiology and Treatment of Complicated Skin and Skin Structure Infections in Diabetic and Nondiabetic Patients in a Population-Based Study.

BACKGROUND: Diabetes is a major risk factor for skin and skin structure infection (SSSI), and the global burden of diabetics with SSSI is enormous. The more complex microbiology of diabetic foot infection (DFI) is well established, but it is not known whether microbiological etiology differs between diabetics and nondiabetics in other disease entities under the umbrella of complicated SSSI (cSSSI). METHODS: This retrospective, population-based study included patients with cSSSI, and it was conducted in 2 Nordic cities with a low prevalence of antimicrobial resistance. In analyses, patients (N = 460) were separated into 3 groups: diabetics (n = 119), nondiabetics (n = 271), and patients with DFI (n = 70). RESULTS: After exclusion of patients with DFI, there was no difference in the microbiological etiology or initial antimicrobial treatment of cSSSI between diabetics and nondiabetics. Gram-positive bacteria encountered 70% of isolations in diabetics and 69% in nondiabetics, and the empirical treatment covered initial pathogens in 81% and 86% of patients, respectively. However, diabetes was the only background characteristic in the propensity score-adjusted analysis associated with broad-spectrum antimicrobial use and longer antibiotic treatment duration. Patients with DFI had Gram-negative and polymicrobial infection more often than nondiabetics. CONCLUSIONS: These observations suggest that diabetics without DFI are not different in the causative agents of cSSSI, although they are more exposed to antimicrobial therapy of inappropriate extended spectrum and long duration. Broad-spectrum coverage was clearly needed only in DFI. A clear opportunity for antimicrobial stewardship was detected in the rapidly growing population of diabetic patients with cSSSI.