Sternal Wound Infection In Patients Research Articles

Sternal Wound Infection Following Open Heart Surgery: Incidence, Risk Factor, Pathogen, and Mortality

Due to its high morbidity and mortality after open-heart surgery, sternal wound infection (SWI) is one of the most important consequences to avoid and manage. To assess the incidence, risk factor, causative organisms, and mortality of SWIs in patients who had open-heart surgery over a 9-year period at King Abdulaziz University Hospital, Jeddah, Saudi Arabia. A retrospective study was done on 634 patients who underwent open heart surgery. Data was collected, including patient demographics, BMI, blood group, diabetes, hyperlipidemia, COPD, previous cardiac surgery, previous myocardial infarction, duration of the operation, blood transfusion during the operation, hospital length of stay, and bypass time with each type of sternal wound infection. The incidence of SSWI and DSWI was 8.6% and 4.1%, respectively. Coagulase-negative staphylococcus was the most frequently isolated organism from SSWI and DSWI patients. A concomitant diabetes mellitus that necessitates blood transfusion was identified as one of the risk variables for SSWI in a multivariate regression study. While concomitant diabetes, being a woman, and a lengthy hospital stay were independently linked with DSWI. Compared with the SSWI group, the 30-day mortality rate for DSWI patients was 3.8% as opposed to 3.7%, and the difference in survival was not statistically significant. Having an older, longer bypass time, and postoperative problems were independent risk factors for 30-day mortality. Future studies in various healthcare settings are required in order to generalize the results because this was a single center study.

The Effect of Birth Month on the Risk of Deep Sternal Wound Infections in Patients After Coronary Artery Bypass Grafting and Heart Defect Surgery.

Cardiovascular diseases remain one of the leading causes of morbidity and mortality worldwide, however its surgical treatment remains risky with possible complications. There is increasing evidence that the month of birth (MOB) has been related to different health problems during life. The aim of this study was to identify the effect of MOB on the risk of deep sternal wound infections (DSWI) in patients after open-heart surgery. The follow-up retrospective research was performed at the Department of Thoracic, Cardiac, and Vascular Surgery of the Hospital of Lithuanian University of Health Sciences. We analyzed the MOB of 201 patients, who underwent open-heart surgery between January 2017 and December 2018. The case group consisted of 46 patients, who suffered from DSWI. Multivariate logistic regression for the association between MOB and risk of DSWI was used. The results showed that the risk of DSWI was by four times higher for patients born in June-September months. The risk of developing DSWI in the case group was even higher for women, patients aged 70 years and younger, those overweight or obese, and patients who underwent only CABG surgery. Due to the growing evidence that the month of birth affects the onset of diseases, it is important to assess MOB as the potential risk factor for developing DSWI.

Risk Factors for Sternal Wound Infection after Coronary Artery Bypass Grafting in Patients with and without Diabetes.

Diabetes mellitus (DM) is a well-known risk factor for sternal wound infections (SWIs). However, SWIs are also known to occur in patients without DM. This study aimed to examine the difference in risk factors for SWIs after coronary artery bypass grafting (CABG) between non-diabetic and diabetic patients.We conducted a retrospective observational study including 6,697 patients who underwent CABG at our hospital from 2015-2018. The patients were assigned to the non-diabetic (group N, n = 2,930) or diabetic (group D, n = 3,767) group. A total of 24 potential risk factors were evaluated using univariate and multivariate analyses. Differences between superficial and deep SWIs were also examined.A total of 209 (3.1%) CABG patients, comprising 47 (22.5%) and 162 (77.5%) in groups N and D, respectively, required surgical treatment for SWIs. Univariate analyses indicated that a body mass index (BMI) > 25 kg/m2 was uniquely associated with superficial SWIs in group N. Moreover, married status may have lowered the risk of deep SWIs in group D. Renal failure, intra-aortic balloon pump (IABP) use, and reopening in group N, as well as female sex, emergency admission, and reopening in group D, were independent predictors of SWI in the multivariate analysis.In this study, reopening was a common risk factor associated with SWIs in patients who underwent CABG with and without DM. Female sex and emergency admission were independent predictors of deep SWIs in patients with DM, whereas renal failure and IABP use were independent predictors of deep SWIs in patients without DM.

Heart valve surgery and the obesity paradox: A systematic review.

Obesity has been associated with increased incidence of comorbidities and shorter life expectancy, and it has generally been assumed that patients with obesity should have inferior outcomes after surgery. Previous literature has often demonstrated equivalent or even improved rates of mortality after cardiac surgery when compared to their lower-weight counterparts, coined the obesity paradox. Herein, we aim to review the literature investigating the impact of obesity on surgical valve interventions. PubMed and Embase were systematically searched for articles published from 1 January 2000 to 15 October 2021. A total of 1315 articles comparing differences in outcomes between patients of varying body mass index (BMI) undergoing valve interventions were reviewed and 25 were included in this study. Patients with higher BMI demonstrated equivalent or reduced rates of postoperative myocardial infarction, stroke, reoperation rates, acute kidney injury, dialysis and bleeding. Two studies identified increased rates of deep sternal wound infection in patients with higher BMI, although the majority of studies found no significant difference in deep sternal wound infection rates. The obesity paradox has described counterintuitive outcomes predominantly in coronary artery bypass grafting and transcatheter aortic valve replacement. Recent literature has identified similar trends in other heart valve interventions. While the obesity paradox has been well characterized, its causes are yet to be identified. Further study is essential in order to identify the causes of the obesity paradox so patients of all body sizes can receive optimal care.

Risk Factors Associated with an Increased Risk of Deep Sternal Wound Infections in Patients After Coronary Artery Bypass Grafting and Heart Defect Surgery

Despite improvements over time with regard to morbidity, mortality, and long-term survival, deep sternal wound infection (DSWI) continues to be a major complication after open-heart surgery. This is why it is important to identify possible risk factors for postoperative development of DSWI in patients undergoing coronary artery bypass grafting and valve replacement. The aim of this study was to identify the risk factors for postoperative development of deep sternal wound infection in patients after coronary artery bypass grafting and heart defect surgery at the Department of Thoracic, Cardiac, and Vascular Surgery of the Hospital of Lithuanian University of Health Sciences. This retrospective study analyzed 201 patients, who underwent coronary artery bypass grafting and heart defect surgery between January 2017 and December 2018. The case group contained 45 patients, who had to be reoperated because of deep sternal wound infection, and the control group consisted of 156 randomly selected patients. For descriptive statistics, we used means, median values, ranges, standard deviations, and 95% confidence intervals, where appropriate. Categorical data were analyzed using the chi-square or Fisher's exact test. Student T-test and Mann-Whitney used to compare numerical variables. Logistic regression model adjusting for age and gender was used to compare the risk of infection. A P-value of < 0.05 was considered to be statistically significant. SPSS 26.0 was used for calculations. Logistic regression analysis revealed that independent risk factors for sternal wound infection were high BMI (odds ratio [OR] 1.15, CI 1.06-1.24), preoperative CRP (OR 1.08, CI 1.01-1.16), long duration of cardiopulmonary bypass (OR 1.02, CI 1.01-1.03), intraoperative anemia (OR 0.97, CI 0.95-0.99), and postoperative CRP concentration (OR 1.10; CI 1.05-1.16). Preoperative assessment to identify obese individuals as being at risk and techniques to minimize the duration of surgery and intraoperative blood loss may help reduce postoperative deep sternal wound infections.

Use of Tropical Vancomycin in Decreasing the Incidence of Surgical Site Infection in Open Heart Surgery

Aim: To study the effect of vancomycin tropically in decreasing the incidence of sternal wound infection in patients undergoing open cardiac surgery. Study design: Randomized controlled trial Place and duration: Department of Cardiovascular &amp; Thoracic Surgery Sheikh Zayed Hospital Lahore from 1st January 2019 to 31st July 2020. Methods: A total of 180 male and female planned for elective open heart surgery is selected for this research work. All patients age is between 40 and 70 years and these patients are bifurcated in two groups. In Group I there are 90 patients in which vancomycin is used on the sternal edges, while in Group II there are 90 patients in which only normal saline wash is used at the time of sternal approximation. At the end incidence of sternal wound infection is monitored to establish the benefits of tropical vancomycin. Results: One hundred and thirty three (73.89%) were males and 47 (26.11%) were females. Topical vancomycin group has decreased rate of superficial and deep sternal wound infections as compared to the patients in which topical vancomycin is not applied (2.22% vs 6.67%) and (1.11% vs 4.4%). Conclusion: Application of vancomycin tropically at surgical site at the time of closure of sternum in conjunction with prophylactic use of antibiotics reduces wound infection in open heart surgery. Keywords: Open heart surgery, Vancomycin, Sternal wound infection

Comparative Study Between the effect of Skeletonized and Pedicled Internal Thoracic Artery on sternum healing in Patient Undergoing CABG

Background: Myocardial revascularization is performed preferentially with internal thoracic artery grafts. This study aimed to investigate sternal healing over time and the incidence of poor sternal healing and wound infection in patients undergoing coronary artery bypass graft (CABG) surgery using skeletonized internal thoracic artery. Objectives: (1) comparison of two surgical take-down techniques (skeletonizing vs. standard pedicle harvestation); (2) assessment of sternal healing and wound infection. Method: This study enrolled 50 patients (divided in two groups) who underwent isolated CABG using skeletonized internal thoracic artery (25 patients) and pedicled internal thoracic artery (25 patients) from December 2017 to August 2019. Postoperative assessment was performed on all patients for three months after surgery. In all patients, chest X-ray study was performed after surgery to assess sternal healing. Medical records were also retrospectively reviewed to identify perioperative variables associated with poor early sternal healing. Results: (1) After coronary grafting, assessment of sternum showed significant differences in healing between the two groups. (2) Diabetes mellitus as an independent predictor for superficial wound infection. (3) Pedicled procedure is an important factor associated with superficial wound infection in post-operative period. (4) Skeletonized procedure prolong the operation. (5) Pedicled procedure prolong the ICU and hospital stay.Conclusion: (1) Skeletonization of internal thoracic artery conduits lowers the risk of superficial and deep sternal wound infection in patients undergoing CABG with internal thoracic artery grafting. (2) Skeletonization of internal thoracic artery conduits prolong the operation time and require more surgical skills. (3) Skeletonization of ITA has better outcome.

Skeletonized versus pedicled left internal mammary artery harvesting and risk of sternal wound infection after coronary artery bypass surgery

Background: The left internal mammary artery (LIMA) is the gold standard conduit for coronary artery bypass grafting (CABG). There are two harvesting methods, either pedicled or skeletonized. The choice of any technique must consider its complication profile, especially sternal wound infections (SWI). This study aims to evaluate and compare the occurrence of SWI after pedicled and skeletonized LIMA harvesting techniques for CABG.&#x0D; Methods: This prospective observational study included 300 patients who had CABG between 2016 and 2019. We included patients who had pedicled LIMA (n=200) in group 1 and who had skeletonized LIMA (n=100) in group 2. All patients completed a follow-up period of 3 months after CABG. The evaluation during follow-up included: sternal instability, signs of wound infection, temperature, the microbiological study of wound discharge, and chest computed tomography scan.&#x0D; Results: There was no significant differences in age (p = 0.20), male to female ratio (p = 0.43), body mass index (p = 0.12), NYHA I/II (p = 0.50), diabetes mellitus (p = 0.28), ejection fraction (p= 0.14), and EuroSCORE II (p= 0.09) between groups. No significant difference in cardiopulmonary bypass time (p = 0.24), and cross-clamp time (p= 0.19) between groups. There was a significant increase in the total operating time in skeletonized LIMA group (212.77±75.25 min vs. 190.78±55 minutes, p= 0.004). Skeletonized LIMA was significantly associated lower incidence of SWI than that with pedicled LIMA (4% vs 15.5%, p= 0.003), and non-significantly lower incidence of deep SWI (1% vs 4.5%, p= 0.11). The risk factors for SWI in patients who had pedicled IMA were obesity (OR: 13.06, 95%CI: 3.98-42.89), diabetes mellitus (OR: 10.51, 95%CI: 2.35-46.84), and excessive diathermy (OR: 12.62, 95%CI: 3.93-40.54).&#x0D; Conclusion: Obesity, diabetes, and the use of excessive diathermy for hemostasis may increase the risk of sternal wound infection with pedicled LIMA harvest compared to skeletonized LIMA in patients undergoing CABG.

Postoperative Deep Sternal Wound Infections in Patients Undergoing Coronary Artery Bypass Surgery

Postoperative Deep Sternal Wound Infections in Patients Undergoing Coronary Artery Bypass Surgery

Topical rifampicin for prevention of deep sternal wound infections in patients undergoing coronary artery bypass grafting

Deep sternal wound infections (DSWI), although an infrequent complication, significantly impair postoperative outcomes after coronary artery bypass grafting (CABG) surgery. Among several preventive strategies, topical antibiotic therapy immediately before sternal closure has been strongly advocated. In this retrospective analysis, the incidence of DSWI in 517 patients undergoing isolated CABG and receiving rifampicin irrigation of mediastinum, sternum and suprasternal tissues was compared to an historical consecutive cohort of 448 patients. To account for the inherent selection bias, a 1:1 propensity matched analysis was performed. Patients receiving topical rifampicin experienced significantly less occurrence of postoperative DSWI (0.2% vs 2.5%, p = 0.0016 in the unmatched analysis; 0.3% vs 2.1%, p = 0.0391 in the matched analysis). Intensive care unit stay, hospital stay, and operative mortality were similar between groups. This study shows that topical rifampicin in combination with commonly prescribed preventative strategies significantly reduces the incidence of DSWI to less than 0.3% in unselected patients undergoing a full median sternotomy for CABG. Further studies, including a larger number of patients and with a randomization design, would establish the potential preventative role of topical rifampicin in reducing the occurrence of DSWI.

The outcomes of Skeletonized and Pedicled Internal Thoracic Artery in Patients undergoing coronary artery bypass grafting: a randomized clinical study

Background: Internal thoracic artery became the cornerstone graft in coronary artery bypass grafting. This study aimed to investigate sternal healing and wound infection in patients undergoing coronary artery bypass graft (CABG) surgery using skeletonized versus pedicled internal thoracic artery.&#x0D; Methods: 100 patients who underwent isolated CABG were divided into two groups; skeletonized internal thoracic artery (ITA) (50 patients) and pedicled internal thoracic artery (50 patients). The postoperative assessment was performed three months after surgery. Physical and radiological examinations were performed after surgery to assess sternal healing.&#x0D; Results: There was no significant difference in patients’ demographics between groups. Skeletonized group had more diabetic patients (65% vs 44%; p= 0.016). There was no significant difference between the two groups regarding the number of grafts (2.72 ± 0.89 vs. 2.68 ± 0.90; skeletonized vs pedicled group; p= 0.84). Harvesting time was longer in the skeletonized group (55.69 ± 8.80 vs. 44.28 ± 6.95 minutes; p=0.09). Superficial wound infection occurred more frequently in the pedicled group (24% vs. 8%; p=0.03).&#x0D; Conclusion: Skeletonization of the internal thoracic artery conduits lowers the risk of superficial and deep sternal wound infection in patients undergoing CABG compared to the pedicled technique. However, skeletonization of internal thoracic artery conduits prolongs the operation time and requires more surgical skills.

Utility of FDG-PET/CT for the Detection and Characterization of Sternal Wound Infection Following Sternotomy.

FDG-PET/CT has the potential to play an important role in the diagnosis of sternal wound infections (SWI). The purpose of this study was to analyze the diagnostic accuracy of FDG-PET/CT for SWI in patients following sternotomy. We performed a single-center, retrospective analysis of patients who had undergone median sternotomy and FDG-PET/CT imaging. The gold standard consisted of positive bacterial culture and/or the presence of purulent material at surgery. Qualitative patterns of sternal FDG uptake, SUVmax, and associated CT findings were determined, and an imaging scoring system was developed. The diagnostic performances were studied in both the recent (≤ 6months between sternotomy and imaging) and remote surgery phase (> 6months). A total of 40 subjects were identified with 11 confirmed SWI cases. Consensus interpretation was associated with a sensitivity of 91% and specificity of 97%. Combination of uptake patterns yielded an AUC of 0.96 while use of SUVmax yielded an AUC of 0.82. Results suggest that FDG-PET/CT may be useful for the diagnosis of SWI with optimal diagnostic accuracy achieved by identifying specific patterns of uptake. SUVmax can be helpful in assessing subjects with remote surgery, but its use is limited in the context of recent surgery. Further studies are required to confirm these results.

AIncisional Negative Pressure Wound Therapy (INPWT) for Coronary Artery Bypass Grafting Patients

Background: Surgical site infections are major complications of coronary artery bypass grafting using bilateral internal thoracic arteries. In this study we reviewed the results of using INPWT for high risk patients with coronary artery bypass grafting (CABG) using bilateral internal mammary arteries. Patients and methods: From January 2013 to December 2016, patients with coronary artery bypass grafting using bilateral mammary arteries were enrolled in this study. Patients were from Kasr El-Einy, Beni-Suef and Fayoum University Hospitals. The total number was 427 patients, where INPWT was used in 161 patient, and conventional sterilized dressing was done in 266 patients. 2 groups were matched for statistical analysis, the first group was the control and the second group was where INPWT was used. Results: The results related to sternal wound infections were similarly attributed to the conventional group (10.9%) and the INPWT group (10.2%) (P=1.00). Patients treated with INPWT had less rate of infection than those with conventional dressing (5.5% versus 10.2%, P= 0.210), this difference was not statistically significant. Interaction tests also showed comparable results for SSI (surgical site infections) among patients with or without significant co-morbidities. Conclusion: This study suggests that the use of INPWT did not decrease the incidence of sternal wound infections in patients who had CABG surgery using bilateral internal mammary harvesting (BIMA). A larger randomized study is needed to evaluate the efficacy of this technique.

Glycated Hemoglobin and the Risk of Sternal Wound Infection After Adult Cardiac Surgery: A Systematic Review and Meta-Analysis

Increased glycated hemoglobin (HbA1c) has been shown to increase the risk of mortality, myocardial infarction, and stroke after cardiac surgery, whereas its impact on the development of sternal wound infection (SWI) is less clear. A systematic review and meta-analysis were performed to evaluate the impact of preoperative HbA1c levels on the occurrence of SWI after adult cardiac surgery. Fourteen studies including 17,609 patients fulfilled the inclusion criteria and were included in this analysis. Diagnostic test meta-analysis of studies evaluating baseline HbA1c cut-off values ranging from 6% to 7% DCCT units (42-53 mmol/mol IFCC units) showed that the diagnostic odds ratio for deep SWI was 3.02 (95% confidence interval [CI] 2.10-4.35), while the diagnostic odds ratio for any SWI was 2.81 (95% CI 2.02-3.93). Binary meta-analysis confirmed that baseline HbA1c cut-off values ranging from 6% to 7% increased the risk for deep SWI (pooled incidence 2.7% vs 0.8%, risk ratio [RR] 3.01, 95% CI 2.32-3.90, I2 0%). Six studies included only diabetics and their pooled RR for deep SWI was 2.94 (1.59-5.45, I2 0%). Nine studies evaluated an HbA1c cut-off value of 7% and their RR for deep SWI was 3.22 (95% CI 2.38-4.37, I2 0%). The RR for any SWI was 2.92 (95% CI 2.42-3.53, I2 0%). This pooled analysis showed that the risk of SWI is substantially increased when preoperative HbA1c levels are over 6-7%. Future studies should evaluate whether postponing surgery for optimization of the glycemic control can reduce the risk of SWI in patients with increased levels of HbA1c.

PREDICTING THE PROBABILITY OF THE STERNAL WOUND INFECTION IN PATIENTS UNDERGOING CARDIAC SURGERY

objective. The aim of the study is to create the model for predicting the probability of the sternal wound infection in patients undergoing cardiac surgery after heart operations with the use of longitudinal median sternotomy. Material and methods. The results of treatment of 485 cardiosurgical patients were analyzed; these patients were divided into 2 groups. In the 1st group (265 patients), the prophylaxis of sternal infection was carried out according to a standard procedure, the method of «elimination of sternal infection» was applied in the 2nd group (220 patients). The rate of sternal infection was estimated depending on risk factors. The multiple logistic regression was used to create the model for predicting the risk of sternal wound infection. Results. The created model for predicting the risk of sternal wound infection includes the following factors: application of the method of «elimination of sternal infection» (OR=1871.9; p=0.036); diabetes mellitus type 2 (OR=0.207; p=0.022); the risk according to EuroScore Logistic (OR=1.04; p=0.04); the duration of stay in ICU (OR=1.15, p=0.006). Conclusion: The created model for predicting the risk of sternal wound infection in cardiosurgical patients is excellent effective (p=0.036). The proposed technique for the prevention of sternal infection allowed to reduce the incidence of its occurrence in patients from 7.9 to 0.45 %.

Intraoperative local administration of antibiotics for prevention of sternal wound infection in cardiac surgery

Aim. The article compares the effects of local and systemic use of antibiotics on the incidence of sternal wound infection in patients undergoing cardiac surgery.Methods. 485 patients undergoing adult cardiac surgery for the incidence of sternal wound infection were retrospectively evaluated. The patients were divided into two groups who received systemic (cefazolin) and topical (vancomycin, gentamicin) administration of antibiotics for the prevention of sternal wound infection in the postoperative period. The incidence of sternal wound infection depending on the method of application of antibiotics was also assessed.Results. According to the results of the statistical analysis, intraoperative topical application of antibiotics (vancomycin and gentamicin) significantly reduced the cases of sternal wound infection from 7.9 to 0.45% (odds ratio of 1871.9; 95% confidence interval 1.67-2.1×106; p = 0.036). Thus, to improve the efficiency of impact on the pathogenic flora in the wound and to reduce the risk of sternal infection, topical application of antibacterial drugs: vancomycin for the cancellous bone of the sternum, gentamicin for irrigation of tissue during suturing the wound is one of the methods. Conclusion. As a result of the comparative analysis, prevention of sternal wound infection in cardiac patients with intraoperative topical antibiotics is more effective than systemic antibiotic prophylaxis. To reduce the risk of sternal wound infection, topical application of vancomycin as a putty for the cancellous bone of the sternum and gentamicin for irrigation of the soft tissue in the process of wound suturing is recommended.Received 16 August 2016. Accepted 22 November 2016.Conflict of interest: The authors declare no conflict of interest.Financing: The study had no sponsor’s support.

Continuous postoperative insulin infusion reduces deep sternal wound infection in patients with diabetes undergoing coronary artery bypass grafting using bilateral internal mammary artery grafts: a propensity-matched analysis.

Deep sternal wound infection (DSWI), especially in patients with diabetes mellitus (DM), is a major concern after coronary artery bypass grafting (CABG) with bilateral internal mammary artery (BIMA) grafts. We evaluated the risk of DSWI and other clinical outcomes between continuous insulin infusion therapy (CIT) and insulin sliding scale therapy (IST) in a cohort of DM patients who underwent CABG with BIMA. The clinical records of DM patients who underwent isolated CABG with BIMA were retrospectively reviewed. The study population consisted of 95 patients who received CIT and 126 patients who received IST. Furthermore, a one-to-one matched analysis based on estimated propensity scores for patients who received CIT or IST yielded two groups comprising 58 patients each. The proportion of patients with DSWI, overall survival rates and major adverse cardiac events were compared between the two groups in the overall and the propensity-matching cohort. The prevalence of DSWI requiring debridement and closure was significantly reduced in the CIT group compared with that in the IST group [1/95 (1.1%) vs 9/126 (7.1%), P = 0.031]; these results were not attenuated even after propensity-matching analysis [0/58 (0%) vs 6/58 (10.3%), P = 0.031]. The mean preoperative glucose levels were similar between the two groups (157.5 ± 54.6 vs 176.1 ± ±70 mg/dl, P = 0.063), whereas the mean glucose values were significantly lower on the first and second operative days in the CIT group than in the IST group (132.9 ± 44.1 vs 197.8 ± 78.6 mg/dl, P < 0.0001; 153.5 ± 58.8 vs 199.6 ± 89.1 mg/dl, P < 0.0001, respectively). The glucose variability levels within 24 h postoperatively were significantly higher in the IST group (46.1 ± 19.4 vs 66.4 ± 26.8 mg/dl, P < 0.0001). The 30-day and 1-year survival rates were similar between the two groups (100 vs 99.2%, P = 0.384; 96.6 vs 94.4%, P = 0.454). No results were changed in the propensity-matching models. The CIT approach reduced the variability in glucose concentration and resulted in fewer instances of DSWI after CABG with BIMA grafts.

Total arterial coronary revascularization

Arterial coronary grafts can be used in the majority of patients and have better patencies than saphenous vein grafts (SVGs), resulting in excellent perioperative and superior long-term outcomes. Barriers to their extensive use include potential for trauma and spasm, extra-operating time, unfamiliarity, concerns over hypoperfusion and deep sternal wound infection in patients in whom bilateral internal thoracic arteries are used-especially diabetics. This presentation addresses these concerns with particular attention to the radial artery, and skeletonized right internal thoracic artery harvest and construction of the proximal anastomoses of these grafts to the ascending thoracic aorta. The facile handling of these grafts and techniques identical to SVG grafting are emphasized. Avoidance of competitive flow and the importance of spasm prophylaxis cannot be overstated. Arterial grafts have patencies >90% at 10 years (SVG 50-60% at 10 years) and once functioning normally, remain free of atheroma. Long-term results are excellent, especially freedom from recurrent cardiac events and reoperations, even in patients with significant preoperative comorbidities such as diabetes and renal dysfunction. Depending on age, long-term survival is between 85 and 90% at 10 years and 75 and 80% at 15 years, and is always better than for one arterial graft plus SVG in all long-term risk-adjusted or propensity-matched studies.

Preoperative Hematocrit Is a Powerful Predictor of Adverse Outcomes in Coronary Artery Bypass Graft Surgery: A Report From The Society of Thoracic Surgeons Adult Cardiac Surgery Database

Small series have identified a relationship between preoperative hematocrit (HCT) and outcomes in coronary artery bypass graft (CABG) surgery. The Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database (ACSD) began collecting preoperative HCT data in 2008. In this study, analyses were performed to determine the impact of preoperative HCT on perioperative morbidity and mortality among patients undergoing isolated CABG. Data were collected on 182,599 patients who underwent primary isolated on-pump CABG between 2008 and 2009 and were included in the STS ACSD. Data were included only from centers that performed more than 100 on-pump cases per year during the period of study. Dialysis patients as well as those with previous cardiovascular operations or missing data for HCT were excluded. We then performed multivariable analysis using the 2008 STS CABG risk model as a guide, including HCT as a predictor. Logistic regression was performed for operative mortality and other adverse outcomes. Overall operative mortality was 1.6% (3,005 of 182,599). Compared with patients with anemia (HCT <33%), patients with HCT of at least 42% had lower mortality (1.1% versus 3.4%; p < 0.0001) and lower rates of renal failure (2.0% versus 7.8%; p < 0.0001), stroke (0.9% versus 1.8%; p < 0.0001), prolonged ventilation (8.4% versus 17.5%; p < 0.0001), and deep sternal wound infection (0.3% versus 0.6%; p < 0.0001). In adjusted analyses, each 5-point decrease in preoperative HCT was associated with an 8% higher odds of death (odds ratio, 1.08; p = 0.0003), a 22% increase in the odds of postoperative renal failure (odds ratio, 1.22; p < 0.0001), and a 10% increase in the risk of deep sternal wound infection (odds ratio, 1.10; p < 0.01). Similar results were observed among patients (n = 74,292) undergoing elective CABG. The percentage of patients receiving perioperative blood transfusion decreased from 88.5% in the anemic group (HCT <33%) to 32.5% in patients with HCT of at least 42% (p < 0.0001). Preoperative HCT is a powerful independent predictor of perioperative mortality as well as renal failure and deep sternal wound infection in patients undergoing isolated primary CABG operations. These findings should prompt investigation of strategies to increase preoperative HCT.

EComment. Prevention of sternal wound infection

We read with great interest the article by Sakic et al. [1] assessing the efficacy of surgical modifications on the incidence of postoperative sternal complications after bilateral internal thoracic arteries (BITA) harvesting. In this single-center retrospective study, the authors demonstrated that using a skeletonized approach in patients receiving bilateral internal thoracic arteries with augmented sternal wires is effective in preventing sternal wound complications. As described by others, this series supports the claim that the risk of sternal infection can be reduced by performing internal thoracic artery harvested in a skeletonized manner. Deo et al. [2] conducted the first systematic review and meta-analysis to address the essential clinical question of whether BITA increases the risk of deep sternal wound infection in patients with diabetes; they concluded that the risk may be minimized using a skeletonized approach. The left internal thoracic artery to left anterior descending artery graft has long been established as the cornerstone of improved early and late outcomes in surgically-treated patients. An overwhelming wealth of evidence, mainly retrospective studies, demonstrated that the use of BITA as bypass grafts provided superior early survival and better event-free survival after coronary artery bypass grafting. The Arterial Revascularization Trial [3] is the only randomized study comparing the outcomes of single internal mammary artery (SITA) vs BITA, with a primary outcome of survival at 10 years, and results should be available in five years. The risk of sternal wound complications may need to be weighed against the long-term benefit of BITA grafts. It is, needless to say, that anterior mediastinitis is a rare but ominous complication after BITA harvesting, carrying a high risk of in-hospital mortality. Many factors have been suggested as responsible for postcardiotomy sternal wound infection, and investigations to prevent this dreaded complication are still considered as a greatly researched topic in cardiac surgery. Recently, Grauhan et al. [4] investigated the efficacy of a new commercially available negative pressure wound therapy system (Prevena Incision Management System; KCI, San Antonio, USA) as a dressing treatment to prevent sternal wound infection in obese patients undergoing cardiac surgery. They showed in a prospective study that the application of a special foam as a wound dressing immediately after skin closure and negative pressure of -125 mmHg for the first 6 to 7 days postoperatively significantly reduces the incidence of sternal infection in this high-risk patient population. The technique of skeletonization during BITA harvest preserves sternal microacirculation [5]; the immediate application of a negative-pressure wound dressing after suturing prevents the breakdown of skin sutures and seepage of bacteria into the deeper layers. These two different methods showed to be effective in reducing the likelihood of sternal wound infection, and should be considered in high-risk patients of sternal complications. Conflict of interest: none declared.