Deep sternal wound infection: the role of early debridement surgery

Debridement for surgical wounds

BACKGROUND

Surgical wounds that become infected are often debrided because clinicians believe that removal of this necrotic or infected tissue may expedite wound healing. There are numerous methods of debridement available, but no consensus on which one is most effective for surgical wounds.

OBJECTIVES

To assess the effects of different methods of debridement on the rate of debridement and healing of surgical wounds.

SEARCH METHODS

In October 2021, we searched the Cochrane Wounds Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL. To identify additional studies, we searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies, reviews, meta-analyses, and health technology reports. There were no restrictions on language, date of publication, or study setting.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that enrolled people with a surgical wound that required debridement, and reported time to complete wound debridement or time to wound healing, or both.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, risk of bias assessment using the RoB 1 tool, data extraction, and GRADE assessment of the certainty of evidence.

MAIN RESULTS

In this fourth update, we identified one additional study for inclusion. The review now includes six studies, with 265 participants, aged three to 91 years. Five studies were published between 1979 and 1990 and one published in 2014. The studies were carried out in hospital settings in China, Denmark, Belgium, and the UK. Six studies provided six comparisons. Due to the heterogeneity of studies, it was not appropriate to conduct meta-analyses. Four studies evaluated the effectiveness of dextranomer beads/paste; however, each study used a different comparator (Eusol-soaked dressings, 10% aqueous polyvinylpyrrolidone, 0.1% chloramine-soaked packs, and silicone foam elastomer dressing). One study compared streptokinase/streptodornase with saline-soaked dressings, and one compared endoscopic surgical debridement with conventional 'open' surgical debridement. Five studies reported time to complete debridement (reported as time to a clean wound bed) and three reported time to complete healing. One study reported effect estimates (surgical debridement via endoscopy versus surgical debridement) for time to a clean wound bed and time to complete wound healing, and it was possible to calculate effect estimates for one other study (dextranomer paste versus silicone foam elastomer) for time to complete wound healing. For the other four studies that did not report effect estimates, it was not possible to calculate time to a clean wound bed or time to complete wound healing due to missing variance and participant exclusions. None of the included studies reported outcomes pertaining to proportion of wounds completely healed, rate of reduction in wound size, rate of infection, or quality of life. All studies had unclear or high risk of bias for at least one key domain. Dextranomer paste/beads (autolytic debridement) compared with four different comparators Four studies compared dextranomer paste or beads with Eusol-soaked gauze (20 participants), 10% aqueous polyvinylpyrrolidone (40 participants), 0.1% chloramine-soaked dressings (28 participants), or silicone foam elastomer (50 participants). There is very low-certainty evidence that there may be no clear difference in time to a clean wound bed between dextranomer beads and Eusol gauze. The study did not report adverse events. There is very low-certainty evidence that there may be no difference in time to a clean wound bed between dextranomer paste and 10% aqueous polyvinylpyrrolidone gauze. There was low-certainty evidence that there may be no difference in deaths and serious adverse events. There may be a difference in time until the wounds were clinically clean and time to complete wound healing between dextranomer paste and 0.1% chloramine favouring 0.1% chloramine, but we are very uncertain. There is low-certainty evidence that there may be no difference in deaths and serious adverse events. There is very low-certainty evidence that there may be no difference in time to complete healing between dextranomer beads and silicone foam elastomer. The study did not report adverse events. Streptokinase/streptodornase solution (enzymatic) compared with saline-soaked dressings One study (21 participants) compared enzymatic debridement with saline-soaked dressings. There is low-certainty evidence that there may be no difference in time to a clean wound bed or secondary suture between streptokinase/streptodornase and saline-soaked dressings. There is very low-certainty evidence that there may be no difference in deaths and serious adverse events. Surgical debridement via endoscopic ('keyhole') surgery compared with surgical debridement by 'open' surgery (the wound is opened using a scalpel) One study (106 participants) reported time to complete wound healing and time to a clean wound bed. There is low-certainty evidence that there may be a reduction in time to complete wound healing and very low-certainty evidence that there may be no difference in time to a clean wound bed with surgical debridement via endoscopy compared to 'open' surgical debridement. The study did not report adverse events. Overall, the evidence was low to very low-certainty for all outcomes. Five included studies were published before 1991 and investigated treatments that are no longer available. Worldwide production of dextranomer products has been discontinued, except for dextranomer paste, which is currently only available in South Africa. Furthermore, Eusol, used in one study as the comparator to dextranomer, is rarely used due to risk of harmful effects on healthy tissue and the enzymatic agent streptokinase/streptodornase is no longer available worldwide.

AUTHORS' CONCLUSIONS

Evidence for the effects of different methods of debridement on complete wound debridement and healing of surgical wounds remains unclear. Adequately powered, methodologically robust RCTs evaluating contemporary debridement interventions for surgical wounds are needed to guide clinical decision-making.

Antibiotic therapy in reconstructive surgery of deep sternal wound infections

BACKGROUND

The choice of antibiotics and length of administration in the treatment of deep sternal wound infections (DSWI) is unclear. The reason for this is the lack of studies and local differences in resistance. An increase in resistance can be observed in gram-positive cocci, which are the most frequently detected in deep sternal infections. The duration of administration is often 2- 6 weeks or longer, although the benefit of prolonged antibiotic administration has not been confirmed by studies. We evaluated the antibiotic treatment during surgical treatment, consisting of surgical wound debridement and plastic chest reconstruction.

METHODS

Retrospective analysis of patients (n = 260) who underwent reconstructive surgery in the Department of Plastic Surgery at Leipzig University Hospital from 01.05.2012 - 31.12.2020. The duration of intake, results of microbiological swabs and resistance were investigated.

RESULTS

At the time of discharge, closed wound conditions were noted in 177 of 260 cases (68.1%). The largest proportion of patients (n = 238) was treated with a latissimus dorsi flap (91.5%).Antibiotic treatment was conducted in 206 of 260 cases (79.2%). The mean duration of antibiotic administration was 21.4 days (±17.6). Prolonged treatment over 14 days did not alter outcome (p = 0.226), in contrast, the number of multidrug resistances (p < 0.001). There was no prove of resistance against linezolid which is effective against the most common found infectious agents Staphylococcus epidermidis (n = 93; 24.0 %) & Staphylococcus aureus (n = 47; 12.1 %).

CONCLUSION

There is no evidence of benefit from antibiotic therapy over 14 days, whereas multidrug resistance increases with prolonged antibiotic use. In the absence of infectious agents or clinical signs of inflammation, surgical treatment without additional antibiotic treatment is effective.Linezolid is a suitable antibiotic in the treatment of gram-positive infections which are the most frequent in DSWI.

The Role of Hyperbaric Oxygen Therapy in the Treatment of Surgical Site Infections: A Narrative Review

Surgical site infections (SSIs) are among the most prevalent postoperative complications, with significant morbidity and mortality worldwide. In the past half century, hyperbaric oxygen therapy (HBOT), the administration of 100% oxygen intermittently under a certain pressure, has been used as either a primary or alternative therapy for the management or treatment of chronic wounds and infections. This narrative review aims to gather information and evidence supporting the role of HBOT in the treatment of SSIs. We followed the Scale for the Quality Assessment of Narrative Review Articles (SANRA) guidelines and scrutinized the most relevant studies identified in Medline (via PubMed), Scopus, and Web of Science. Our review indicated that HBOT can result in rapid healing and epithelialization of various wounds and has potential beneficial effects in the treatment of SSIs or other similar infections following cardiac, neuromuscular scoliosis, coronary artery bypass, and urogenital surgeries. Moreover, it was a safe therapeutic procedure in most cases. The mechanisms related to the antimicrobial activity of HBOT include direct bactericidal effects through the formation of reactive oxygen species (ROS), the immunomodulatory effect of HBOT that increase the antimicrobial effects of the immune system, and the synergistic effects of HBOT with antibiotics. We emphasized the essential need for further studies, especially randomized clinical trials and longitudinal studies, to better standardize HBOT procedures as well as to determine its full benefits and possible side effects.

A case of sternal osteomyelitis during treatment with everolimus for recurrent breast cancer

Background

Everolimus is a mechanistic-target-of-rapamycin (mTOR) inhibitor bearing a potent antitumor effect against hormone receptor-positive breast cancer. Here, we report the case of a patient with recurrent breast cancer who developed osteomyelitis during the treatment with everolimus plus exemestane.

Case presentation

A 56-year-old woman with early-stage breast cancer underwent right mastectomy and axillary lymph node dissection at the age of 45. Four years after the surgery, she experienced relapse at the chest wall. Radiotherapy was performed on the chest wall, including the sternum, and denosumab was administered. After several regimens of hormonal therapies, everolimus in combination with exemestane was administered. Three months later, the patient visited our clinic because of continuous fever. A computed tomography scan showed an osteolytic change in the sternal bone with pneumomediastinum, which indicated sternal osteomyelitis. Extensive debridement followed by secondary reconstruction of the chest wall was successfully performed.

Conclusions

Everolimus may cause osteomyelitis of the affected bone as a result of tumor necrosis. Everolimus-induced osteomyelitis may be manageable by extensive debridement performed without delay.

Hyperbaric oxygen therapy as additional treatment in deep sternal wound infections - a single center's experience

INTRODUCTION

Deep sternal wound infection (DSWI) is one of the most serious complications after cardiac surgery procedures, observed in 5% of patients. Current standard medical therapy for DSWI includes antibiotics, surgical debridement, resuturing or negative pressure wound therapy (NPWT). Unfortunately, in some cases these methods are insufficient, and additional therapeutic options are needed.

AIM

To assess the effects and usefulness of additional hyperbaric oxygen therapy (HBO2) in patients with DSWI after cardiac surgery procedures.

MATERIAL AND METHODS

A retrospective analysis of 10 patients after cardiac surgery who developed DSWI in the period 2010-2012 was performed. After 3 months of ineffective conventional therapy including targeted antibiotic, surgical sternal debridement and NPWT, patients were qualified for additional HBO2 therapy. A total of 20 sessions of HBO2 therapy were performed, each 92 minutes long.

RESULTS

After 4 weeks of HBO2 treatment, 7 patients presented complete wound healing with fibrous scar formation. One patient was qualified for the another cycle of HBO2 therapy with 20 additional sessions, and complete wound healing was observed. In 2 cases, after 5 and 19 sessions, HBO2 was interrupted because of improper qualifications.

CONCLUSIONS

The HBO2 as an additional therapy in DSWI was successful in 80% of cases, and no complications were observed. However, due to the small number of published studies with a small number of patients, randomized, clinical trials are needed to assess the clinical results of HBO2 in DSWI after cardiac surgery procedures.

Can Drainage Using a Negative-Pressure Wound Therapy Device Replace Traditional Sample Collection Methods?

BACKGROUND

In 2015 a new device for the collection of mediastinal fluid from patients with deep sternal wound infection (DSWI) in the presence of negative-pressure wound therapy (NPWT) became available. The present study was designed to evaluate whether changing sample collection devices increased micro-organism detection in patients undergoing NPWT.

METHODS

During 2013-2014, 207 samples were collected and cultured from NPWT patients (n = 23) to demonstrate the presence of DSWI using reticulated polyurethane sponge culture, a swab, and blood culture. In 2015, a new collection device was introduced for specimen collection. A total of 357 samples (n = 17) were collected using the ESwab(™) (Copan, Murrieta, CA) for deep and superficial wound sample collection. In addition, blood culture devices were used for collecting mediastinal fluid aspirated directly from the wound and biologic fluid obtained from the NPWT device. Fisher exact test was performed to test the rate of independence rate of micro-organism identification using the NPWT sponge device and taking blood culture results as a reference for micro-organism identification.

RESULTS

After the introduction of the new collection device in our hospital, an overall increase in the detection of micro-organisms (46.7%) was reported. During 2013-2014 our traditional microbiologic collection method did not detect a pathogen in 30.4% of patients. During 2015, the new sample collection approach, direct from the NPWT device, improved micro-organism detection by 10.4% and reduced DSWIs with undetected pathogens to 17.6% (p < 0.01).

CONCLUSIONS

As a result of proficiency gained in the last year, the most representative specimen in wound infection was represented by mediastinal fluid collected directly from the wound and the NPWT device. Given the correlation between the blood culture of micro-organisms detected using the ESwab device from the wound, mediastinal drainage, and drainage from the NPWT device, we can assume that the NPWT device may replace the other biologic sampling devices.

A National Study of the Impact of Initial Débridement Timing on Outcomes for Patients with Deep Sternal Wound Infection

BACKGROUND

Excisional débridement for patients with deep sternal wound infection is a main component of treatment. This study aims to evaluate the impact of delayed excisional débridement on mortality and associated outcomes.

METHODS

The authors analyzed the MarketScan database from 2009 to 2013 to identify patients with deep sternal wound infection who received surgical intervention. A logistic regression model was created to model mortality. Poisson regression models were used to model number of procedures, number of hospitalizations, and length of stay. A log-linear regression model was used for cost analysis. All analyses were adjusted for patient risk factors.

RESULTS

The final cohort included 1335 patients with 12 percent in-hospital mortality. There was considerable variation in timing of débridement among patients with deep sternal wound infection, with more than 25 percent undergoing initial débridement 4 or more days after diagnosis, and 10 percent undergoing débridement more than 1 week after diagnosis. Patients undergoing delayed débridement had progressively higher risk for greater number of admissions and total hospital days compared with those undergoing early débridement. Patients undergoing débridement on the day of diagnosis of deep sternal wound infection had a predicted 34 total hospital days, compared with 49 total hospital days for patients undergoing débridement more than 7 days after diagnosis.

CONCLUSIONS

Patients treated with early surgical intervention had fewer hospital admissions and fewer hospital days than patients undergoing delayed surgical treatment. Protocols to facilitate early débridement have the potential to improve quality and efficiency of deep sternal wound infection care.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Successful Outcome of Mediastinitis After 26 Days Delay in Diagnosis

Acute mediastinitis, which is characterized by inflammation of thoracic tissues, is a life-threatening infection and a surgical emergency. The mortality rate for this ailment is reported between 14-42%, which makes it important to diagnose and treat as soon as possible. We presented and discussed a case of a 38-year-old male patient with blunt trauma to the chest and back from falling who reported to the emergency department after 26 days with severe chest pain and a toxic condition. He underwent an anterolateral thoracotomy and several rounds of pleural flushing; ultimately, he survived.

Debridement for surgical wounds

BACKGROUND

Surgical wounds that become infected are often debrided because clinicians believe that removal of this necrotic or infected tissue will expedite wound healing. There are numerous methods available but no consensus on which one is most effective for surgical wounds.

OBJECTIVES

To determine the effect of different methods of debridement on the rate of debridement and healing of surgical wounds.

SEARCH METHODS

In March 2013, for this third update, we searched the Cochrane Wounds Group Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE; and EBSCO CINAHL.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) with outcomes including at least one of the following: time to complete debridement or time to complete healing.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed the abstracts and titles obtained from the search, extracted data independently using a standardised extraction sheet and independently assessed methodological quality. One review author was involved in all stages of the data collection and extraction process, thus ensuring continuity.

MAIN RESULTS

Five RCTs (159 participants) were eligible for inclusion; all compared treatments for infected surgical wounds and reported time required to achieve a clean wound bed (complete debridement). One trial compared an enzymatic agent (streptokinase/streptodornase) with saline-soaked dressings. Four trials compared the effectiveness of dextranomer beads or paste with other products (different comparator in each trial) to achieve complete debridement. Meta-analysis was not possible due to the unique comparisons within each trial. One trial reported that dextranomer achieved a clean wound bed significantly more quickly than Eusol, and one trial comparing enzymatic debridement with saline-soaked dressings reported that the enzyme-treated wounds were cleaned more quickly. However, methodological quality was poor in these two trials.

AUTHORS' CONCLUSIONS

There is a lack of large, high-quality published RCTs evaluating debridement per se, or comparing different methods of debridement for surgical wounds, to guide clinical decision-making.

Hyperbaric oxygen therapy as an adjunctive treatment for sternal infection and osteomyelitis after sternotomy and cardiothoracic surgery

Purpose

A retrospective study to evaluate the effect of hyperbaric oxygen (HBO2) therapy on sternal infection and osteomyelitis following median sternotomy.

Materials and methods

A retrospective analysis of patients who received sternotomy and cardiothoracic surgery which developed sternal infection and osteomyelitis between 2002 and 2009. Twelve patients who received debridement and antibiotic treatment were selected, and six of them received additional HBO2 therapy. Demographic, clinical characteristics and outcome were compared between patients with and without HBO2 therapy.

Results

HBO2 therapy did not cause any treatment-related complication in patients receiving this additional treatment. Comparisons of the data between two study groups revealed that the length of stay in ICU (8.7 ± 2.7 days vs. 48.8 ± 10.5 days, p < 0.05), duration of invasive (4 ± 1.5 days vs. 34.8 ± 8.3 days, p < 0.05) and non-invasive (4 ± 1.9 days vs. 22.3 ± 6.2 days, p < 0.05) positive pressure ventilation were all significantly lower in patients with additional HBO2 therapy, as compared to patients without HBO2 therapy. Hospital mortality was also significantly lower in patients who received HBO2 therapy (0 case vs. 3 cases, p < 0.05), as compared to patients without the HBO2 therapy.

Conclusions

In addition to primary treatment with debridement and antibiotic use, HBO2 therapy may be used as an adjunctive and safe treatment to improve clinical outcomes in patients with sternal infection and osteomyelitis after sternotomy and cardiothoracic surgery.

Risk factors and management approach for deep sternal wound infection after cardiac surgery at a tertiary medical centre

BACKGROUND

Deep sternal wound infection (DSWI) is a rare but severe complication following cardiac surgery. Our study investigated the risk factors and treatment options for patients who developed DSWI at our institution between May 1988 and April 2008.

METHOD

Data was collected prospectively in a database and information on demographics reviewed retrospectively on 5649 patients who underwent cardiac surgery during this period.

RESULTS

The incidence of DSWI was 34/5649 (0.6%). These patients were older (mean age 66.1 vs. 64.5), more likely to die (in hospital mortality 11.8% vs. non DSWI group 1.8%) and had longer hospital stays (DSWI group mean stay 25 days vs. non DSWI group 9 days). Using Fisher's exact test the risk predictors for DSWI determined at our institution included diabetes managed with oral medications (p=0.021), previous cardiac surgery (p=0.038), BMI≥30 (p=0.041), LVEF≤30 (p=0.010), IABP usage (p=0.028) and homologous blood usage (p<0.001). Most commonly bilateral pectoralis major muscle flap (BPMMF) was used for treatment of DSWI (11/30, 36.7%).

CONCLUSION

Ultimately our data was comparable to published data in the literature on known risk predictors.

Cross-sectional study of craniocerebral trauma in a tertiary hospital after 2008 Sichuan earthquake: a brief report of 242 cases and experiences from West China Hospital

BACKGROUND

We aim to analyze clinical features of patients with craniocerebral trauma after 2008 Sichuan earthquake in China.

METHODS

Medical records of patients with craniocerebral trauma admitted to Department of Neurosurgery in West China Hospital within 30 days after earthquake were retrospectively analyzed. Demographic data, clinical diagnosis, treatment, and prognosis were reviewed. Patients' data from peripheral hospitals were also analyzed.

RESULTS

Two hundred forty-two patients with craniocerebral injuries were included in the study. The male to female ratio was 1.3:1, and more than half of the patients were between 20 and 60 years. Majority of patients suffered from mild to moderate injuries (88.4%). Scalp wound was the leading type, followed by skull fractures and brain contusion and laceration. Fifty patients (20.7%) underwent craniotomy. Overall mortality was 5.4% (n = 13). In survivors, 186 patients had good outcome (Glasgow Outcome Scale score ≥4, 76.9%). Staphylococcus aureus (n = 74, 44.6%), Aerobacter cloacae (n = 37, 22.3%), and Staphylococcus epidermidis (n = 33, 19.9%) were most frequently isolated bacteria in wound smear. Over 85% (n=6) of patients with infectious wound (n=7) obtained delayed first stage healing. Mortality of patients in local hospitals ranged from 3.8% to 8.9%.

CONCLUSIONS

Most patients admitted to tertiary hospitals are mildly or moderately injured. Cooperation among different departments is critical to shorten delay in emergency room. First stage wound healing or delayed first stage healing can be achieved in most patients after treatment. More than 76% of seismic injury patients in a tertiary medical center have good outcome.

Debridement for surgical wounds

BACKGROUND

Surgical wounds that become infected are often debrided because clinicians believe that removal of this necrotic or infected tissue will expedite wound healing. There are numerous methods available but no consensus on which one is most effective for surgical wounds.

OBJECTIVES

To determine the effect of different methods of debridement on the rate of debridement and healing of surgical wounds.

SEARCH STRATEGY

For this second update we searched the Cochrane Wounds Group Specialised Register (searched 13 April 2011); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 1); Ovid MEDLINE (2007 to March Week 5 2011); Ovid MEDLINE (In-Process & Other Non-Indexed Citations, April 11, 2011); Ovid EMBASE (2007 to 2011 Week 14); and EBSCO CINAHL (2007 to 8 April 2011).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) with outcomes including at least one of the following: time to complete debridement or time to complete healing.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed the abstracts and titles obtained from the search, extracted data independently using a standardised extraction sheet and independently assessed methodological quality. One review author was involved in all stages of the data collection and extraction process, thus ensuring continuity.

MAIN RESULTS

Five RCTs (159 participants) were eligible for inclusion; all compared treatments for infected surgical wounds and reported time required to achieve a clean wound bed (complete debridement). One trial compared an enzymatic agent (streptokinase/streptodornase) with saline-soaked dressings. Four trials compared the effectiveness of dextranomer beads or paste with other products (different comparator in each trial) to achieve complete debridement. Meta-analysis was not possible due to the unique comparisons within each trial. One trial reported that dextranomer achieved a clean wound bed significantly more quickly than Eusol, and one trial comparing enzymatic debridement with saline-soaked dressings reported that the enzyme-treated wounds were cleaned more quickly. However, methodological quality was poor in these two trials.

AUTHORS' CONCLUSIONS

There is a lack of large, high-quality published RCTs evaluating debridement per se, or comparing different methods of debridement for surgical wounds, to guide clinical decision-making.

Role of vacuum in methicillin-resistant deep sternal wound infection

Between January 2002 and January 2009, 39 patients with post-cardiotomy staphylococcal deep sternal wound infection were treated primarily by a vacuum-assisted closure method (group A). Results were compared with those of 30 patients with staphylococcal deep sternal wound infection who received closed mediastinal irrigation with antibiotics (group B). The prevalence of methicillin-resistance was similarly high in both groups (64.1% in A, 56.7% in B). One group B patient died during treatment. The median healing time was significantly shorter at 13 days in group A (mean, 13.5 +/- 3.2 days) compared to 18 days (mean, 21.2 +/- 16.4 days) in group B. Deep sternal wound infection did not recur after vacuum treatment, while 7 (24%) patients in group B suffered a recurrence. Hospital stay was significantly shorter in group A (median, 30.5 days; mean, 32.2 +/- 11.3 days vs. median, 45 days; mean, 49.2 +/- 19.3 days). The significantly shorter healing time with vacuum-assisted closure was confirmed in both methicillin-sensitive (12 vs. 17 days) and methicillin-resistant infections (14 vs. 21 days). Hospital stay remained significantly shorter in group A (35 vs. 46 days) when only methicillin-resistant deep sternal wound infection was considered.

Hyperbaric oxygen preconditioning improves myocardial function, reduces length of intensive care stay, and limits complications post coronary artery bypass graft surgery

OBJECTIVE

The objective of this study was to determine whether preconditioning coronary artery disease (CAD) patients with HBO(2) prior to first-time elective on-pump cardiopulmonary bypass (CPB) coronary artery bypass graft surgery (CABG) leads to improved myocardial left ventricular stroke work (LVSW) post CABG. The primary end point of this study was to demonstrate that preconditioning CAD patients with HBO(2) prior to on-pump CPB CABG leads to a statistically significant (P<.05) improvement in myocardial LVSW 24 h post CABG.

METHODS

This randomised control study consisted of 81 (control group=40; HBO(2) group=41) patients who had CABG using CPB. Only the HBO(2) group received HBO(2) preconditioning for two 30-min intervals separated 5 min apart. HBO(2) treatment consisted of 100% oxygen at 2.4 ATA. Pulmonary artery catheters were used to obtain perioperative hemodynamic measurements. All routine perioperative clinical outcomes were recorded. Venous blood was taken pre HBO(2), post HBO(2) (HBO(2) group only), and during the perioperative period for analysis of troponin T.

RESULTS

Prior to CPB, the HBO(2) group had significantly lower pulmonary vascular resistance (P=.03). Post CPB, the HBO(2) group had increased stroke volume (P=.01) and LVSW (P=.005). Following CABG, there was a smaller rise in troponin T in HBO(2) group suggesting that HBO(2) preconditioning prior to CABG leads to less postoperative myocardial injury. Post CABG, patients in the HBO(2) group had an 18% (P=.05) reduction in length of stay in the intensive care unit (ICU). Intraoperatively, the HBO(2) group had a 57% reduction in intraoperative blood loss (P=.02). Postoperatively, the HBO(2) group had a reduction in blood loss (11.6%), blood transfusion (34%), low cardiac output syndrome (10.4%), inotrope use (8%), atrial fibrillation (11%), pulmonary complications (12.7%), and wound infections (7.6%). Patients in the HBO(2) group saved US$116.49 per ICU hour.

CONCLUSION

This study met its primary end point and demonstrated that preconditioning CAD patients with HBO(2) prior to on-pump CPB CABG was capable of improving LVSW. Additionally, this study also showed that HBO(2) preconditioning prior to CABG reduced myocardial injury, intraoperative blood loss, ICU length of stay, postoperative complications, and saved on cost, post CABG.

Debridement for surgical wounds

BACKGROUND

Surgical wounds that become infected are often debrided because clinicians believe that removal of this necrotic or infected tissue will expedite wound healing. There are numerous methods available but no consensus on which one is most effective for surgical wounds.

OBJECTIVES

The aim of this review is to determine the effect of different methods of debridement on the rate of debridement and healing of surgical wounds.

SEARCH STRATEGY

We developed a search strategy to search the following electronic databases: Wounds Group Specialised Trials Register (searched 3/3/08) , Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2008, issue 1), MEDLINE (1950 to February Week 3 2008 ), EMBASE (1980 to 2008 Week 09) and CINHAL (1982 to February Week 4 2008). We checked the citations within obtained studies to identify additional papers and also relevant conference proceedings. We contacted manufactures of wound debridement agents to ascertain the existence of published, unpublished and ongoing trials. Our search was not limited by language or publication status.

SELECTION CRITERIA

We included relevant randomised controlled trials (RCT) with outcomes including at least one of the following: time to complete debridement, or time to complete healing.

DATA COLLECTION AND ANALYSIS

Two authors independently reviewed the abstracts and titles obtained from the search, two extracted data independently using a standardised extraction sheet, and two independently assessed methodological quality. One author was involved in all stages of the data collection and extraction process, thus ensuring continuity.

MAIN RESULTS

Five RCTs were eligible for inclusion; all compared treatments for infected surgical wounds and reported time required to achieve a clean wound bed (complete debridement). One trial compared an enzymatic agent (Streptokinase/streptodornase) with saline-soaked dressings and reported the time to complete debridement. Four of the trials compared the effectiveness of dextranomer beads or paste with other products (different comparator in each trial) to achieve complete debridement. Meta analysis was not possible due to the unique comparisons within each trial. One trial reported that dextranomer achieved a clean wound bed significantly more quickly than Eusol, and one trial comparing enzymatic debridement with saline-soaked dressings reported that the enzyme treated wounds were cleaned more quickly. However methodological quality was poor in these two trials.

AUTHORS' CONCLUSIONS

There is a lack of large, high quality published RCTs evaluating debridement per se or comparing different methods of debridement for surgical wounds, to guide clinical decision making.

Anterior Mediastinal Herniation of the Transverse Colon after an Omental Flap Transposition

Poststernotomy mediastinitis continues to be an infrequent but serious complication after cardiac surgery. We present a case of a 59-year-old man who developed a deep sternal wound infection after an emergency cardiac surgery. Omental transposition flap was used to cover the sternal defect. Several days later, the patient developed a transverse colon herniation into the anterior mediastinum that required emergency exploration and colon resection. The patient survived after a difficult hospital course. Indications, technical points, and possible complications of using omental flap transposition are discussed.

Incidence, microbiological findings, and clinical presentation of sternal wound infections after cardiac surgery with and without local gentamicin prophylaxis

Sternal wound infection (SWI) is a serious complication after cardiac surgery. In a previous randomized controlled trial, the addition of local collagen-gentamicin in the sternal wound before wound closure was found to significantly reduce the incidence of postoperative wound infections compared with the routine intravenous prophylaxis of isoxazolyl-penicillin only. The aims of the present study were to analyse the microbiological findings of the SWIs from the previous trial as well as to correlate these findings with the clinical presentation of SWI. Differences in clinical presentation of SWIs, depending on the causative agent, could be identified. Most infections had a late, insidious onset, and the majority of these were caused by staphylococci, predominantly coagulase-negative staphylococci. The clinically most fulminant infections were caused by gram-negative bacteria and presented early after surgery. Local administration of gentamicin reduced the incidence of SWIs caused by all major, clinically important bacterial species. Propionibacterium acnes was identified as a possible cause of SWI and may be linked to instability in the sternal fixation. There was no indication of an increase in the occurrence of gentamicin-resistant bacterial isolates in the treatment group. Furthermore, the addition of local collagen-gentamicin reduced the incidence of SWIs caused by methicillin-resistant coagulase-negative staphylococci. This technique warrants further evaluation as an alternative to prophylactic vancomycin in settings with a high prevalence of methicillin-resistant Staphylococcus aureus.

Managing sternal osteomyelitis with antibiotic bead implantation

Early, aggressive debridement followed by closure with muscle flaps is thought to improve the resolution of deep sternal wound infection that occurs after sternotomy. However, persistently discharging sternal osteomyelitis remains difficult to resolve. We successfully treated 2 patients who developed deep sternal wound infection after cardiac surgery by combining one-stage debridement with implantation of gentamicin beads to fill up the evacuated bone marrow space. This approach provides a simple and effective solution for sternal osteomyelitis.

Usefulness of routine epicardial pacing wire culture for early prediction of poststernotomy mediastinitis

Poststernotomy mediastinitis (PSM) is one of the most serious complications of cardiac surgery, and its associated morbidity and mortality demand early recognition for emergency therapy. In this study, we investigated the usefulness of epicardial pacing wire (EPW) cultures for the prediction of PSM. Among 2,200 patients who underwent a cardiac surgical procedure at our hospital between 1 January 1999 and 31 December 2001, 82 (3.7%) had PSM; Staphylococcus aureus was the organism (45.1%) most frequently isolated at the time of surgical debridement. EPWs from 1,607 (73.0%) patients, 73 (4.5%) of whom developed PSM, were cultured. EPW cultures from 466 (29.0%) were positive, most often (74.9%) for coagulase-negative Staphylococci. EPW cultures were truly positive in 26 cases, truly negative in 1,106 cases, falsely positive in 428 cases, and falsely negative in 47 cases (with sterile cultures in 35 cases and a culture positive for an organism different from that isolated at the time of debridement in 12 cases). EPW culture had a positive predictive value of only 5.7% and a high negative predictive value (95.9%) for the diagnosis of PSM, with an accuracy of 70.4%. However, the likelihood ratio of positive (1.27) and negative (0.89) tests indicated only small changes in pretest-to-posttest probability. Therefore, a strategy of routine culture of EPWs to predict PSM seems questionable.

Achilles Tendon for Sternal Synthesis in the Treatment of Mediastinitis

Surgical approaches to postoperative mediastinitis that imply wire removal achieve earlier infection recovery but leave the patient with sternal instability. In 10 patients after wound surgical debridement, my colleagues and I achieved sternal synthesis by using Achilles tendons retrieved from multiorgan donors and stored in glutaraldehyde. Three tendons were used in each patient; they were passed through the bone at the manubrium and parasternally at the midsternum and the lower sternum. Thirty-day computed tomographic scan results, infection recovery, and quality of life were satisfactory.

Management of Sternal Wounds With Pectoralis Major Musculocutaneous Advancement Flaps in Patients With a History of Chest Wall Irradiation

Although debridement and pectoralis major musculocutaneous advancement flap closure has proved to be an effective treatment of sternal wounds in the general population, the purpose of this study was to examine the use of these flaps in patients with previously irradiated chest walls. The authors examined 5 patients with a history of breast cancer and chest wall radiation therapy who developed poststernotomy wound complications that were treated with debridement and pectoralis major musculocutaneous advancement flaps. The average patient age was 76 years. Three patients had previously undergone a radical mastectomy and had only 1 pectoralis major muscle remaining. There were no intraoperative deaths. One patient died during the 30-day postoperative period. There were no hematomas, seromas, or dehiscences. One woman developed a postoperative wound infection. Functional and aesthetic results were excellent. This study demonstrates that early, aggressive sternal debridement and closure with pectoralis major musculocutaneous advancement flaps is effective in patients with a history of chest wall irradiation, including those who have had 1 pectoralis major muscle previously resected.

Mediastinitis after pediatric cardiac surgery: a 15-year experience at a single institution

BACKGROUND

The spectrum of sternal wound infections after cardiac surgery ranges from superficial infections to a deep sternal infection known as mediastinitis. Mediastinitis is a rare but clinically relevant source of postoperative morbidity and mortality in adult and pediatric patients after cardiac surgery.

METHODS

We retrospectively identified all patients diagnosed with mediastinitis after cardiac surgery from January 1987 to December 2002 (17 patients/7,616 surgeries = 0.2%). Demographic data, cardiac diagnosis, cardiac surgery, hospital length of stay, associated medical diagnosis, and surgical treatment for mediastinitis were collected.

RESULTS

Fifteen pediatric patients (age < 18 years) were diagnosed with mediastinitis (mean age at diagnosis 37.5 months, range 21 days to 17 years. The median postoperative day of diagnosis was 14 days (6 to 50 days). The most common organism was Staphylococcus species (n = 9). Six patients had an associated bacteremia. The median hospital length of stay for all patients was 42.5 days (range 16 to 163 days). The hospital mortality was 1 of 15 (6%). Each patient was treated with intravenous antibiotics; sternal debridement; and rectus abdominus flap reconstruction (n = 7), pectoralis muscle flap reconstruction (n = 3), omentum reconstruction (n = 1), or primary sternal closure (n = 4). Three patients have undergone redo-sternotomy with orthotopic heart transplantation, bidirectional cavopulmonary anastomosis, and replacement of a right ventricle to pulmonary artery homograft.

CONCLUSIONS

Timely diagnosis, aggressive sternal debridement, and liberal use of rotational muscle flaps can potentially minimize the morbidity and mortality in pediatric postoperative cardiac patients. Subsequent redo-sternotomy has not been problematic.

[A descriptive analysis of a series of patients diagnosed with acute mediastinitis]

Acute mediastinitis is one of the most aggressive chest diseases. The mortality rate ranges between 14% and 42%. We present a retrospective analysis of a series of 26 cases (20 men and 6 women) treated between January 1994 and March 2002 and review the literature. Mediastinitis originated in the esophagus in 17 patients (8 postoperative, 4 due to iatrogenic perforation, 4 due to noniatrogenic perforation, and 1 due to a foreign body) and in the oropharynx in 6 patients; mediastinitis was secondary to median sternotomy in 3. Twenty-five patients were treated surgically. In addition to radical debridement and drainage, which were carried out on all the patients, 10 also underwent esophagectomy or resection of the esophago-gastric reconstruction, 5 received primary sutures of the esophagus, 1 received reconstructive surgery with a pectoral muscle flap, and 1 underwent sternectomy plus intrathoracic omental transposition. Four patients died within 30 days of surgery (15.4%). The mortality rate in our practice is similar to that described in the literature. The results argue for early, aggressive treatment.

Treatment of recurrent staphylococcal mediastinitis: still a controversial issue

BACKGROUND

Although surgical management with early debridement and closed mediastinal irrigation has proved successful in reducing early mortality following poststernotomy deep sternal wound infection, recurrence rates are still up to 20%. This study compared the effectiveness and safety of wound dressing with granulated sugar versus early muscle flap surgery in the management of recurrent postoperative Staphylococcal mediastinitis.

METHODS

Between January 1995 and January 2002, 25 patients with severe recurrent staphylococcal mediastinitis were treated with granulated sugar wound dressing (group A) or with wound debridement, v-shape sternectomy and associated muscle flap surgery (group B). Clinical outcomes and perioperative data were analyzed. Outcomes were compared between the groups evaluating the length of time for normalization of white blood cell (WBC) count and of body temperature and length of hospital stay. Patient characteristics determining best treatment option were identified. Survival and incidence of recurrence at follow-up were also analyzed.

RESULTS

Study groups proved homogenous as to preoperative characteristics. Complete cure was achieved earlier in group A than in group B (defervescence: p = 0.0005; WBC normalization: p = 0.0001, respectively). Hospital stay was shorter in group A. A statistically significant difference was found in hospital mortality (16% overall) between the two groups with better outcomes in group A (p = 0.039). In the patient subset with the most severe preoperative profile (hemodialysis, tracheostomy, inotropic support) surgical treatment produced worse results than the sugar dressing method (p 0.048). No case of recurrence was observed.

CONCLUSIONS

Both treatments proved effective in recurrent type IV A Staphylococcal mediastinitis. Granulated sugar proved a safer option in severely compromised patients.