Deep sternal wound infection (DSWI) is a serious complication after open-heart surgery. We investigated the association between DSWI and short- and long-term all-cause mortality in a large well-defined nationwide population. A retrospective, nationwide cohort study, which included 114676 consecutive patients who underwent coronary artery bypass grafting (CABG) and/or valve surgery from 1997 to 2015 in Sweden. Short- and long-term mortality was compared between DSWI patients and non-DSWI patients using propensity score inverse probability weighting adjustment based on patient characteristics and comorbidities. Median follow-up was 8.0 years (range 0–18.9). Altogether, 1516 patients (1.3%) developed DSWI, most commonly in patients undergoing combined CABG and valve surgery (2.1%). DSWI patients were older and had more disease burden than non-DSWI patients. The unadjusted cumulative mortality was higher in the DSWI group compared with the non-DSWI group at 90 days (7.9% vs 3.0%, P < 0.001) and at 1 year (12.8% vs 4.5%, P < 0.001). The adjusted absolute difference in risk of death was 2.3% [95% confidence interval (CI): 0.8–3.9] at 90 days and 4.7% (95% CI: 2.6–6.7) at 1 year. DSWI was independently associated with 90-day [adjusted relative risk (aRR) 1.89 (95% CI: 1.38–2.59)], 1-year [aRR 2.13 (95% CI: 1.68–2.71)] and long-term all-cause mortality [adjusted hazard ratio 1.56 (95% CI: 1.30–1.88)]. Both short- and long-term mortality risks are higher in DSWI patients compared to non-DSWI patients. These results stress the importance of preventing these infections and careful postoperative monitoring of DSWI patients.

Surgical site infection following spine surgery is associated with increased morbidity and mortality. Perioperative antibiotic prophylaxis is a key factor in lowering the risk of acquiring an infection. Previous studies have assessed perioperative cefuroxime concentrations in the anterior column of the cervical spine with an anterior surgical approach. However, the majority of surgeries are performed in the posterior column and many surgeries involve the lumbar spine. The objective of this study was to compare the perioperative tissue concentrations of cefuroxime in the anterior and posterior column during lumbar spine surgery with a posterior surgical approach. In vivo experimental pharmacokinetic study of cefuroxime concentrations in an acute preclinical porcine model. The lumbar vertebral column was exposed from L1 to L5 in 8 female pigs. Microdialysis catheters were placed for sampling in the anterior column (vertebral body) and posterior column (posterior arch) within the same vertebra (L5). Cefuroxime (1.5 g) was administered intravenously. Microdialysates and plasma samples were continuously obtained over 8 hours. Cefuroxime concentrations were quantified by Ultra High Performance Liquid Chromatography Tandem Mass Spectrometry. The primary endpoint was the time above the cefuroxime clinical breakpoint minimal inhibitory concentration (T>MIC) for Staphylococcus aureus of 4 µg/mL. The secondary endpoint was tissue penetration (AUC_tissue/AUC_plasma). Mean T>MIC 4 µg/mL (95% confidence interval) was 123 min (105-141) in plasma, 97 min (79-115) in the anterior column and 93 min (75-111) in the posterior column. Tissue penetration (95% confidence interval) was incomplete for both the anterior column 0.48 (0.40-0.56) and posterior column 0.40 (0.33-0.48). T>MIC was comparable between the anterior and posterior column. Mean cefuroxime concentrations decreased below the clinical breakpoint minimal inhibitory concentration for S. aureus of 4 µg/mL after 123 minutes (plasma), 97 minutes (anterior column) and 93 minutes (posterior column). This is shorter than the duration of most lumbar spine surgeries, and therefore alternative dosing regimens should be considered in posterior open lumbar spine surgeries lasting more than 1.5 hours. Open lumbar spine surgery often involves extensive soft tissue dissection, stripping and retraction of the paraspinal muscles which may impair the local blood flow exposing the lumbar vertebra to postoperative infections. A single intravenous administration of 1.5 g cefuroxime only provided sufficient prophylactic target tissue concentrations in the vertebra of the lumbar spine for up to 1.5 hours.

Background and purpose: Minimally invasive spine surgery has continuously evolved for specific surgical procedures and patient populations to lower morbidity and the risk of postoperative bacterial infection. Perioperative antibiotic prophylaxis is an important preventive measure and local tissue concentrations can be quantified with microdialysis. Insertion of spinal implants induces tissue trauma and inflammation, which may affect antibiotic proximate implant concentrations. We compared perioperative cefuroxime concentrations inside a cannulated pedicle screw used in minimally invasive spine surgery with the opposite non-instrumented vertebral pedicle.Materials and methods: Microdialysis catheters were placed inside a cannulated pedicle screw and in the opposite non-instrumented vertebral pedicle of the same vertebra (L1) in 8 female pigs through a posterior lumbar surgical approach. Following a single-dose intravenous cefuroxime administration (1.5 g), dialysates and plasma were dynamically sampled over 8 hours. The primary endpoint was time above the cefuroxime clinical breakpoint minimal inhibitory concentration for Staphylococcus aureus of 4 μg/mL (T>MIC4).Results: Median T>MIC4 was 0 h (range 0–0) inside the cannulated pedicle screw, 1.6 h (range 1.1–2.4) in non-instrumented vertebral pedicle, and 1.9 h (range 1.9–2.9) in plasma.Conclusion: A single-dose intravenous cefuroxime administration provided low and subtherapeutic concentrations for prevention of infection inside a cannulated pedicle screw in the lumbar spine. Therapeutic concentrations were achieved in the opposite non-instrumented vertebral pedicle up to 1.5–2 h. Therefore, additional prophylactic strategies may be considered in cannulated instrumented spine surgery, especially in high-risk patients. Alternative dosing regimens seem relevant in lumbar spine surgery lasting longer than 1.5 h.

Tracheostomy decannulation leaves an iatrogenic passage in the upper airways. Inadequate sealing leads to pulmonary dysfunction and reduced voice quality. This study aimed to investigate the feasibility and impact of intratracheal tracheostomy sealing on laryngeal airflow and voice quality immediately after decannulation (ClinicalTrials.gov: NCT06138093). Fifteen adult, tracheostomized, intensive care unit patients were included from our hospital. A temporary, silicone-based sealing disc was inserted in the tracheostomy wound immediately after decannulation. Spirometry with measurement of forced vital capacity (FVC), forced expiratory volume in the first second (FEV₁), and peak expiratory flow (PEF) were performed as measures of airway flow. Voice recordings were assessed using an equal appearing interval scale from 1 to 5. Median FVC, FEV₁, PEF, and voice quality score with interquartile range (IQR) was 883 (510–1910) vs. 1260 (1005–1723) mL (p < 0.001), 790 (465–1255) vs. 870 (617–1297) mL (p < 0.001), 103 (55–211) vs. 107 (62–173) mL (p = 0.720), and 2 (1–2.5) vs. 4 (3–5) points (p < 0.001), respectively, with open tracheostomy vs. after sealing the tracheostomy with the intratracheal sealing disc. This feasibility study showed that tracheostomy sealing with the intratracheal disc was safe and led to immediate improvements in FVC, FEV₁, and voice quality.

To assess the mechanical properties of small intestinal submucosal extracellular matrix (SIS-ECM) iterations and choose the optimal version for evaluating functional geometrics after posterior mitral valve reconstruction. Four SIS-ECM versions (2- and 4-ply vacuum-pressed and lyophilized) underwent uniaxial tensile testing. A posterior mitral valve reconstruction patch was developed based on MRI scans (n = 5). Posterior mitral valve reconstruction using 2-ply vacuum-pressed SIS-ECM was performed (n = 7), and geometrics were evaluated using a modified left heart simulator. The vacuum-pressed iterations displayed superior maximum stress values compared to lyophilized (2-ply: median [IQR], 15.8 [15.2–19.0] vs 7.9 [7.3–8.3] MPa, p < 0.001; 4-ply: median (IQR), 15.8 –[14.6–22.0] vs 7.9 [7.6–8.4] MPa). All reconstructed valves were competent with preserved total leaflet area, but individual leaflet segment areas were redistributed. Posterior mitral valve reconstruction with our 2-ply vacuum-pressed SIS-ECM patch design was feasible in vitro. Further in vivo evaluation is warranted. Graphical Abstract

Background and PurposeOptimal antibiotic prophylaxis is crucial to prevent postoperative infection in spinal surgery. Sufficient time above the minimal inhibitory concentration (fT > MIC) for relevant bacteria in target tissues is required for cefuroxime. We assessed cefuroxime concentrations and fT > MIC of 4 mu g center dot ml(-1) for Staphylococcus aureus in the intrathecal (spinal cord and cerebrospinal fluid, CSF) and extrathecal (epidural space) compartments of the lumbar spine. Experimental ApproachEight female pigs were anaesthetized and laminectomized at L3-L4. Microdialysis catheters were placed for sampling in the spinal cord, CSF, and epidural space. A single dose of 1500 mg cefuroxime was administered intravenously over 10 min. Microdialysates and plasma were obtained continuously during 8 h. Cefuroxime concentrations were determined by ultra-high-performance liquid chromatography. Key ResultsMean fT > MIC (4 mu g center dot ml(-1)) was 58 min in the spinal cord, 0 min in the CSF, 115 min in the epidural space, and 123 min in plasma. Tissue penetration was 32% in the spinal cord, 7% in the CSF, and 63% in the epidural space. Conclusion and ImplicationsfT > MIC (4 mu g center dot ml(-1)) and tissue penetration for cefuroxime were lower in the intrathecal compartments (spinal cord and CSF) than in the extrathecal compartment (epidural space) and plasma, suggesting a significant effect of the blood-brain barrier. In terms of fT > MIC, a single dose of 1500 mg cefuroxime seems inadequate to prevent intrathecal infections related to spinal surgery for bacteria presenting with a MIC target of 4 mu g center dot ml(-1) or above.