Faulty sternotomy and complications after median sternotomy

Extensive suprasternal dehiscence reconstruction with NPWT and advancement flaps following cardiac surgery

Treatment of suprasternal wound infection (SSWI) following cardiac surgery is not a clearly developed procedure. We report our female patient's secondary SSWI treatment following bypass surgery. An obese female patient with unstable angina underwent an urgent, uneventful off-pump coronary artery bypass operation. An SSWI appeared within a week. After negative pressure wound therapy (NPWT), the sternum was rewired. In the previously irradiated territory of the left breast necrosis formed, a plastic surgeon reconstructed a defect. This procedure failed NPWT was restarted again, and a secondary reconstructive plastic surgery intervention was necessary. Despite extensive tissue mobilization, the central part of the reconstructive area necrotized, and we had to cover it with a split thickness skin mash graft. The irradiation therapy increases the incidence of suprasternal and/or sternal infection. It was possible to manage large soft tissue defects with bilateral and rotational advancement flaps.

Central venous catheter placement leading to an emergent paramedian sternotomy: a case report

Perioperative cardiac tamponade during central venous catheter placement is rare. We present a case of tamponade from pulmonary artery injury during dialysis catheter placement resulting in complicated sternotomy and hospital course. A 52-year-old female experienced intraoperative hypotension, rapidly identified as tamponade, that was treated with an emergent paramedian sternotomy. Patient experienced postdischarge dehiscence and osteomyelitis requiring multiple reoperations. This case is the first report of a deviated paramedian sternotomy performed mainly through ribs. The complications experienced outline the importance of effective multidisciplinary knowledge of best practices to stabilize tamponade pathology, mitigating morbidity and mortality.

Analysis of sternal healing after median sternotomy in low risk patients at midterm follow-up: retrospective cohort study from two centres

Background

For low risk patients undergoing median sternotomies, no midterm follow-up studies involving sternal healing have been conducted. In this study we evaluated sternal healing in low risk patients by chest CT scan and the risk factors associated with poor healing were analyzed.

Methods

Patients who underwent sternal median incision heart surgery from September 2014 to March 2015 were recruited. The clinical information of these patients during hospitalization was collected, and the CT scan data were submitted to the two chief physicians of the Radiology Department for radiographical sternal healing score determination. Based on the method of wound closure, the patients were divided into sternum plate (Plates) and wire groups (Wires).

Results

Forty-four patients were recruited. The mean CT examination time was 17.27 ± 2.30 months postoperatively. Twenty-nine (65.9%) patients met the criteria for radiographic sternal healing. Three segments, including the aortopulmonary window, the main pulmonary artery, and the aortic root, had healed less in comparison to the manubrium segment. Compared to patients in whom 6–7 metal wires were used for sternal closure, healing of the lower sternum was worse in patients in whom five wires were used, but the difference in healing was not statistically significant. Univariate analysis of sternal healing showed that patient age was a risk factor for sternal non-healing. When the patient age was > 45 years, the predicted risk of radiographic sternal non-union was 1.833 (95% CI: 1.343–2.503).

Conclusions

At the mid-term follow-up, 65.9% of patients undergoing median sternotomies demonstrated radiographic sternal healing. Age, but not closure device, was a risk factor for sternal non-healing in low risk patients. Use of more wires had a positive impact on sternal healing.

Trial registration

researchregistry4918, registered 28 May 2019, retrospectively registered.

Efficacy of new multimodal preventive measures for post-operative deep sternal wound infection

BACKGROUND

Deep sternal wound infection (DSWI) is a critical complication of cardiovascular surgery. This study aimed to confirm the efficacy of new, multimodal preventive measures for post-operative DSWI.

METHODS

From January 2008 to December 2012, 1240 patients underwent cardiovascular surgery via median sternotomy at our hospital. The patients were divided into two groups according to the period in which surgery was performed: those treated before and those treated after January 2011, which was when we implemented the new preventive measures against DSWI. The preventive measures included routine use of an off-pump technique in coronary artery bypass grafting, higher body temperature of pump cases, screening and pre-operative eradication of nasal methicillin-resistant Staphylococcus aureus colonization, and use of a microbial sealant. We compared the incidence of DSWI between the two time periods. Univariate and multivariate analyses were also performed for the entire period to identify DSWI risk factors.

RESULTS

Only 1 case (0.2%) of DSWI was noted among 554 patients in the latter period while 25 patients (3.6%) experienced DSWI among the 686 patients in the earlier period (p < 0.0001). The risk factors for DSWI were body mass index (BMI) ≥ 25 kg/m² and operation time ≥ 8 h.

CONCLUSIONS

We observed a marked decrease in the incidence of DSWI after the implementation of multimodal preventive measures. The risk factors for DSWI were BMI ≥ 25 kg/m² and operation time ≥ 8 h.

European Association for Cardio-Thoracic Surgery expert consensus statement on the prevention and management of mediastinitis

Mediastinitis continues to be an important and life-threatening complication after median sternotomy despite advances in prevention and treatment strategies, with an incidence of 0.25-5%. It can also occur as extension of infection from adjacent structures such as the oesophagus, airways and lungs, or as descending necrotizing infection from the head and neck. In addition, there is a chronic form of 'chronic fibrosing mediastinitis' usually caused by granulomatous infections. In this expert consensus, the evidence for strategies for treatment and prevention of mediatinitis is reviewed in detail aiming at reducing the incidence and optimizing the management of this serious condition.

Asymmetric sternotomy and sternal wound complications: assessment using 3-dimensional computed tomography reconstruction

OBJECTIVE

Wound complications after midline sternotomy result in significant morbidity and mortality. Despite many known risk factors, the influence of sternal asymmetry has largely been ignored. The purpose of this study was to assess the utility of 3-dimensional computed tomographic scan reconstructions to assess sternal asymmetry and determine its relationship with sternal wound infection.

METHODS

A retrospective chart review was conducted for patients who underwent midline sternotomy and received a postoperative computed tomographic scan between 2009 and 2010. Cases were composed of all patients who had a sternal wound infection after undergoing sternotomy. Controls were randomly selected from patients without poststernotomy wound complications. Sternal asymmetry was defined as the difference between the left and the right sternal halves and was expressed as a percentage of the total sternal volume.

RESULTS

Twenty-six cases were identified and 32 controls were selected as described earlier. The patients were similar in baseline characteristics and risk factors including age, sex, smoking status, diabetes, chronic obstructive pulmonary disease, preoperative creatinine, and operative time. Univariate factors associated with sternal wound infection include an asymmetry of 10% or greater, body mass index, and internal mammary artery harvest. In a multivariate logistic regression, independent predictors of sternal wound infection included an asymmetry of 10% or greater (odds ratio, 3.6; P = 0.03) and diabetes (odds ratio, 3.3; P = 0.0442).

CONCLUSIONS

Our data suggest an association between asymmetric sternotomy and sternal wound infections. We recommend an assessment of sternal asymmetry to be performed in patients with sternal wound infection and if it is found to be 10% or greater, the surgeon should implement measures that stabilize the sternum.

Sternal weave in high-risk patients to prevent noninfective sternal dehiscence

Dehiscence of the sternum is a serious and potentially devastating complication. The purpose of this prospective study was to determine whether a prophylactic sternal weave would decreased the incidence of noninfective sternal dehiscence, compared to routine sternal closure, in a high-risk group. Between 2000 and 2007, 200 patients undergoing median sternotomy for cardiac surgery, with one or more risk factors including New York Heart Association functional class III/IV, chronic obstructive pulmonary disease, osteoporosis, obesity, and off-midline sternotomy, were randomly assigned to group A (sternal weave closure, 100 patients) or group B (routine sternal wire closure, 100 patients). No patient in either group with a single risk factor had sternal dehiscence. The incidence of noninfective sternal dehiscence was significantly less in group A than group B in patients with 2 or more risk factors (2.5% vs. 12.5%). Routine sternal closure is sufficient in patients with a single risk factor, whereas a prophylactic sternal weave should be carried out in all patients with 2 or more risk factors, to decrease postoperative morbidity.

Technique to prevent inadvertent paramedian sternotomy

Previous reports documented the relationship between inadvertent paramedian sternotomy and postoperative sternal instability and dehiscence.We describe a modification of the technique of median sternotomy in order to prevent inadvertent paramedian sternotomy and related wound complications.

Performance of a novel sternal synthesis device after median and faulty sternotomy: mechanical test and early clinical experience

BACKGROUND

Reinforcement of chest closure may be required in patients with multiple risk factors of wound dehiscence. Performance of a light, size-adaptable closure reinforcement device (DSS: Sternal Synthesis Device; Mikai SpA, Vicenza, Italy) is presented.

METHODS

A longitudinal median or paramedian incision was performed in artificial sternal models: closure was accomplished with simple interrupted steel wires or reinforced with the DSS. Forces required for separation of the rewired sternal halves during a monotonic tensile test were analyzed. A high velocity traction cycles test was also adopted to simulate the impact of coughing.

RESULTS

After median incision, ultimate load values inducing break of the sternum models were 580 +/- 35 N (Newton) in controls; failure of the test occurred at 1,200 +/- 47 N in the reinforced group (p = 0.0002). More lateral displacement of sternal halves at increasing forces was observed in controls (p = 0.0001). After paramedian incision, ultimate load values inducing break of the constructs were lower in controls (220 +/- 20 N vs 500 +/- 25 N, p = 0.001), which also showed more lateral displacement of sternal halves than the reinforced group (p = 0.002). At the high velocity traction cycles test, the number of cycles required to break the models was lower in controls (2,250 +/- 35 vs 3,855 +/- 48 cycles, p = 0.0001). Preliminary clinical experience in 45 patients showed ease of implantation and low risk of complications.

CONCLUSIONS

The proposed sternal reinforcement device provides substantial sternal support at electromechanical testing after median and faulty sternotomy and may hopefully prevent sternal wires migration and bone fractures in high risk patients.

Clinical outcomes of noninfectious sternal dehiscence after median sternotomy

BACKGROUND

Infectious complications of median sternotomy carry significant morbidity and mortality. However, the outcomes of noninfectious sternal dehiscence have not been addressed. We have identified the preoperative characteristics, postoperative complications, and long-term functional outcomes of patients after reoperation for noninfectious sternal dehiscence and compared these patients with a control group to determine risk factors for dehiscence.

METHODS

Retrospective review of the cardiac surgery database identified 48 patients with noninfectious sternal dehiscence in a group of 12,380 median sternotomies between 1994 and 2004. The review included diagnosis, demographics, concomitant medical conditions, and surgical outcomes. Functional outcomes were assessed using the Short Form-12 questionnaire. One hundred fifty-six median sternotomy patients served as controls. Follow-up was 97.9% (47 of 48 patients) complete, for a total of 150.1 patient-years.

RESULTS

Mean age of patients at reoperation was 58.8 +/- 12.8 years, with a male to female ratio of 45:3. Multivariate analysis determined that New York Heart Association class IV, obesity, and chronic obstructive pulmonary disease were preoperative risk factors for sternal dehiscence. The incidence of sternal dehiscence was 0.39% at a mean interval between initial operation and reoperation of 5.4 months. At a mean interval of 3.9 months, 14.6% (7 of 48) of patients required additional sternal procedures. Infectious complications after reoperation occurred in 12.5% (6 of 48). Functional outcomes demonstrated that 72.2% (26 of 36) had no or mild limitation of physical activities, with 90.5% (38 of 42) reporting no or mild sternal pain at follow-up.

CONCLUSIONS

Although patients undergoing surgical correction of noninfectious sternal dehiscence fare better than those with infectious complications, optimal sternal approximation during the initial procedure and sternal precautions during convalescence should be emphasized to prevent recurrent complications.

Influence of sternal size and inadvertent paramedian sternotomy on stability of the closure site: a clinical and mechanical study

BACKGROUND

The influence of sternal size and of inadvertent paramedian sternotomy on stability of the closure site is not well defined.

METHODS

Data on 171 consecutive patients undergoing cardiac surgery through a midline sternotomy were prospectively collected. Intraoperative measurements of sternal dimension included thickness and width at the manubrium, the third and fifth intercostal spaces; paramedian sternotomy was defined as width of one side of the sternum equaling 75% or more of the entire width, at any of the three levels. The chest was closed with simple peristernal steel wires and inspected to detect deep wound infection and/or instability for 3 postoperative months. The sternal factors and several patient/surgery-related factors were included in a multivariate analysis model to identify factors affecting stability. An electromechanical traction test was conducted on 6 rewired sternal models after midline or paramedian sternotomy and separation data were analyzed.

RESULTS

Chest instability was detected in 12 (7%) patients and wound infection in 2 (1.2%). Patient weight (P = .03), depressed left ventricular function (P = .04), sternum thickness (indexed to body weight, P = .03), and paramedian sternotomy (P = .0001) were risk factors of postoperative instability; paramedian sternotomy was the only independent predictor (P = .001). The electromechanical test showed more lateral displacement of the two rewired sternal halves after paramedian than midline sternotomy (P = .002); accordingly, load at fracture point was lower after paramedian sternotomy (220 +/- 20 N vs 545 +/- 25 N, P = 0.001).

CONCLUSIONS

Inadvertent paramedian sternomoty strongly affects postoperative chest wound stability independently from sternal size, requiring prompt reinforcement of chest closure.

Composite Plate and Wire Fixation for Complicated Sternal Closure

Many techniques have been described to achieve closure of complicated median sternotomy wounds. The standard method of closure uses stainless steel wiring of the sternal halves; however, in complicated sternal closures, sternal cut-through and wire failure can occur. Recent literature advocates the use of fixation plates that achieve bony union, with plating across the median sternal osteotomy site as a singular method. We describe a technique of composite closure using titanium fixation plates to buttress the sternum in combination with circumferential stainless steel wires. This composite technique has been used in 6 patients with complicated sternal closures. Successful wound closure without complication was achieved in all cases. The technique and the clinical series with an illustrative example are presented. The use of plate and wire fixation represents an alternate method to conventional techniques to achieve sternal closure, stability, and uncomplicated wound healing in these difficult-to-manage cases.

Methods for reduction of sternal wound infection

Deep sternal wound infections continue to be an uncommon but potentially devastating complication of cardiac surgical procedures. Numerous risk factors have been identified but only a few can be characterized as modifiable. These risk factors and their modifications are reviewed in the following article.

Prevention and management of deep sternal wound infection

Deep sternal wound infection (DSWI) is an uncommon but serious complication of median sternotomy in cardiac surgery, associated with significant mortality and morbidity. We performed a retrospective review of 30,102 consecutive cardiac surgical patients operated on at our institution from 1990 to 2003 and found an incidence of DSWI of 0.77%. The in-hospital mortality rate was 6.9% for DSWI patients versus 2.8% for patients without DSWI (P = 0.0002). Multivariable predictors for development of DSWI were old age, diabetes, previous stroke or TIA, and congestive heart failure. The use of bilateral internal thoracic artery (BITA) grafts increased the risk of DSWI in patients undergoing coronary artery bypass surgery, particularly in those with congestive heart failure alone or with diabetes. Skeletonization of BITA grafts resulted in a lower risk of DSWI, comparable to nondiabetic patients (1.3% versus 1.6%, P = 0.8). Patients with DSWI were treated with either sternal debridement and primary closure or sternectomy with myocutaneous flap reconstruction, resulting in a 6-month freedom from adverse event rate of 76% in both groups.

Superficial wound dehiscence after median sternotomy: surgical treatment versus secondary wound healing

BACKGROUND

Superficial wound dehiscence after midline sternotomy is considered a minor complication in cardiac surgery, although it is quite frequent and requires prolonged medical treatment. It can be managed conventionally by topical treatment, with delayed secondary healing, or by surgical treatment and primary skin closure. We report the outcome of 96 patients who underwent conventional treatment, compared with a second group of 42 patients who underwent surgical treatment and direct closure.

METHODS

From October 1999 to December 2002, 2400 consecutive patients underwent median sternotomy: 207 patients had sternal wound complications: 3 patients (0.125%) had mediastinitis, 66 patients (2.75%) had aseptic deep sternal wound dehiscence, and 138 patients (5.75%) had superficial wound dehiscence. The latter are the object of the present study; patients entered a protocol of skin wound care on an outpatient basis. The first 96 consecutive patients (group 1) required medications three times a week until complete healing. The last 42 patients (group 2) were treated by extensive surgical debridement of skin and subcutaneous tissue, direct closure of the superficial layers, and suture removal after 15 days.

RESULTS

The two groups were comparable as to age, sex, and preoperative risk factors. The incidence of contaminated wounds was similar in the two groups (32 of 96 in group 1 and 11 of 42 in group 2; p = NS). The length of treatment was 29.7 days (range 2 to 144 days) for group 1 and 12.2 days (range 2 to 37 days) for group 2 (p < 0.0001). The mean number of medical treatments was 9.4 per patient in group 1 and 3.7 per patient in group 2 (p < 0.0001).

CONCLUSIONS

Surgical debridement and primary closure of superficial surgical wound dehiscence after median sternotomy is a safe and valid treatment. Wound infection is not a contraindication to surgical treatment. Primary closure may contribute to reduce the risk for later infection. It also definitely contributes to decreasing healing time and strongly lessens patients' discomfort, diminishing hospital costs and hospital staff workload.

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.

Suppurative mediastinitis after open-heart surgery: a comparison between cases caused by Gram-negative rods and by Gram-positive cocci

OBJECTIVE: To compare clinical characteristics and risk factors of suppurative postsurgical mediastinitis according to its etiology. METHODS: Suppurative postsurgical mediastinitis developed in 45 (2.5%) of 1779 patients who underwent open-heart surgery at the Hospital Virgen del Rocío in Seville, Spain, from 1986 to 1996. Microbiological diagnosis was available in 42 patients. RESULTS: Gram-negative rods were isolated in 19 cases and Gram-positive cocci in 23 cases. Seventeen isolates (38%) were sensitive to the antimicrobial agent used perioperatively. Patients with Gram-negative rod infection had a longer duration of bypass (127plus minus36 min versus 96plus minus34 min, p<0.01), and a worse postoperative condition. Longer mechanical ventilation (4plus minus7 days versus 1plus minus2 days, p<0.05) and concomitant infection in a remote site (pulmonary and/or urinary infection) were more frequently observed in this group than in patients with Gram-positive infections (58% versus 22%, p<0.05). Twenty patients (51%) were bacteremic. The mortality rate was 20% (five of 45). CONCLUSIONS: Preventable postoperative remote-site infection may lead to mediastinitis, especially if Gram-negative rods are involved.

A rational approach to wound difficulties after sternotomy: the problem

One hundred fifty-one patients with mediastinitis after median sternotomy were treated by a single surgeon over a 6-year period. The infections were analyzed in regard to the depth of infection, time of presentation, and the mediastinal defect. Preoperative evaluations included computed tomographic (CT) scans, testing for sternal stability, and the level of contamination. Intraoperative evaluations included bone, inflammatory tissues, Gram stain, and cultures. Treatment options included rewire procedures (20 patients), immediate reconstruction (63 patients), or delayed reconstructions (88 patients). The issues of exposed prosthetic material, right ventricular laceration, long-term intravenous antibiotics, Candida infections, and reexploration of the healed mediastinum after flap reconstruction are discussed. The overall approach to postoperative healing difficulties after sternotomy is examined.

Treatment of sternal nonunion with the Dall-Miles cable system

We have used this technique in two patients. One had early sternal dehiscence with presternal infection, and the other had late sternal nonunion. Uncomplicated sternal union was achieved in both patients. The cables were nonpalpable in both patients, but they were removed in one patient at that patient's request. This method of using Dall-Miles cerclage cables is a straightforward and efficacious method of open reduction and internal fixation of the sternum. It is indicated for patients with chronic sternal nonunion or early postoperative separation of the sternal fragments and may be used even in the presence of an infection limited to the presternal space after adequate debridement and irrigation have been performed. Any recurrent superficial infection, although unlikely, can be cured by hardware removal after osseous union has been obtained. For sternal separation without fractures, four cables may simply be placed around the sternal halves and their tension increased. In the case of sternal fractures, the cables may be placed in figures of eight or in other woven configurations as needed for each individual case.

Transposition of the great omentum for infected sternotomy wounds in cardiac surgery. Report of 16 cases and review of published reports

The expanding indications for coronary artery bypass graft (CABG) and cardiac valves replacement have caused an increase in the number of sternal infections. The common treatment includes appropriate antibiotics, early debridement, and transposition of muscle flaps with or without skin grafts. When other treatments have proved unsatisfactory, we have used the great omentum for wound closure. During the last five years, 16 patients (10 women, six men, median age 63 years) underwent repair of infected sternotomy wounds by the transposition of the great omentum, after failure of pectoralis major or rectus abdominis muscle flaps (n = 9). Seven patients underwent transposition of the great omentum as the first choice. The omentum covers the sternal defect well and the closure was reliable.

Mediastinitis after cardiovascular operations: a case-control study of risk factors

BACKGROUND

An analysis of risk factors for postoperative mediastinitis can lead to a better understanding of the pathogenesis of this complication and to more effective preventive measures.

METHODS

This case-control study of 37 patients and 74 matched controls evaluated 54 potential risk factors.

RESULTS

Nine variables were significantly associated with increased risk of postoperative mediastinitis: total operation time (p = 0.0013), high body-mass index (p = 0.0033), use of beta-adrenergic drugs before the onset of infection (p = 0.0037), long cardiopulmonary bypass time (p = 0.0072), long aortic cross-clamp time (p = 0.0075), presence of diabetes (p = 0.0122), high body weight (p = 0.0130), and use and duration of temporary pacing wires (p = 0.0293 and p = 0.0241 respectively). In a conditional logistic regression analysis, use of beta-adrenergic drugs before the onset of infection (p = 0.0058; odds ratio 19.7; 95% confidence limits, 2.37 and 163.7) and body mass index (p = 0.0082; odds ratio 1.27; 95% confidence limits, 1.06 and 1.52) were independently associated with a significantly increased risk of postoperative mediastinitis.

CONCLUSIONS

Obesity and use of beta-adrenergic drugs, which is indicative of obstructive respiratory problems, were the most important risk factors suggesting that mechanical strain on the sternotomy and sternal instability may precede infection. Targeted preventive measures for these groups could be justified.

Microfibrillar collagen (Avitene) and antibiotic-containing fibrin-glue after median sternotomy

A technique to control bleeding before closure of median sternotomy after cardiac procedures is described. This technique is useful in patients when conventional methods of hemostasis are ineffective because of hypocoaguability, sternal fracture, or friable sternum.

Postoperative mediastinitis: classification and management

Although the incidence of mediastinal wound infection in patients undergoing median sternotomy for cardiopulmonary bypass is less than 1%, its associated morbidity, mortality, and "cost" remain unacceptably high. There is considerable lack of consensus regarding the ideal operative treatment of complicated median sternotomy wounds. The aim of this article is to review the current preventive, diagnostic, and therapeutic techniques offered to patients with mediastinitis. We also propose a new classification for postoperative mediastinitis. Data from the English-language literature suggest that the type of mediastinitis and direct assessment of the mediastinum under general anesthesia are the main determinants of the nature of subsequent operative treatment. Wound debridement and removal of foreign materials are essential steps of whatever procedures are applied. Closed mediastinal irrigation can be successful in type I mediastinitis, whereas major reconstructive operation is probably the treatment of choice for patients with mediastinitis types II to V. Refinement of the current diagnostic tools and further evaluation of the benefits of primary sternal fixation in combination with a reconstructive procedure in mediastinitis types I to III could improve the outcome of this dreaded complication.

Omental transfer for the treatment of sternal infection after cardiac surgery: report of three cases

Sternal infection is an uncommon but serious complication following cardiac surgery. We report herein three cases of postoperative sternal osteomyelitis successfully treated by omental transfer. Two patients had undergone valve surgery and the other underwent division of an accessory pathway for Wolff-Parkinson-White syndrome. Gram-positive organisms were identified in cultures of the exudate in all three patients, as Staphylococcus epidermidis in two and Methicillin-resistant Staphylococcus aureus in one, and concomitant mediastinitis was demonstrated by computed tomography in two cases. Each patient initially underwent sternal debridement and closed irrigation with 0.5% povidone-iodine solution, following which the cultured exudate from two of the patients was negative. The omentum was transferred in two of the patients because they had poor granulation tissue and in the third patient to fill a large dead space, and the postoperative course was uneventful in all three patients. Thus, we conclude that omental transfer is a useful technique for the treatment of postoperative sternal osteomyelitis.

Early postoperative sternal approximation after ITA harvesting: computed tomographic evaluation

Between November 1989 and February 1990, 66 randomized sternotomized patients underwent aortocoronary bypass and were subjected to a sternal scanner in the early postoperative period. Each examination included a manubrial and a sternal body print. At each level, we studied the occurrence of spacing or misalignment of the sternal layers. The 66 patients were subdivided into four groups according to the type of conduit harvested (single left internal thoracic artery or saphenous vein) and the type of material used for the sternal closure (steel wires or nylon yarns). In all cases, adequate early sternal approximation, which is represented by a good alignment as well as by an excellent contact of the sternal layers, was infrequently demonstrated. Moreover, the two abnormalities most often observed were manubrial spacing and sternal body misalignment. The sternal closure technique and internal thoracic artery harvesting had no significant effect on the sternal approximation. To minimize manubrial spacing and sternal body misalignment, we propose that the surgeon should apply three threads through the manubrium, withdraw the shoulder roll beforehand, elevate both of the patient's shoulders, and maintain the two xyphoid layers in the same plane and in fairly close contact during the tightening of the wires.

Reinforced sternal closure

A technique of reinforced sternal closure with stainless steel struts is described. Stable sternum avoids severe complications such as mediastinitis and sternal dehiscence.

Management of deep sternal wound infection after cardiac surgery--Hanuman syndrome

Deep sternal wound infection following open-heart surgery caused sternal osteitis in eight patients and mediastinitis in 27 during 1980-1989. The incidence of such infection was 0.5%. Infection was more common during the last 2 years than in 1980-1987 (0.8% vs. 0.4%), and when bilateral internal mammary artery grafts were dissected (3.2% vs. 0.6% when only one internal mammary artery was used). Cure of mediastinitis was achieved by primary closed irrigation in four of 13 patients and by primary open treatment in five of ten. Muscle flap was employed in totally ten patients and omentum in four before final elimination of infection. Of the 27 patients with mediastinitis, eight (30%) died in the post-operative period of cardiac failure (3 cases), disseminated infection (2), bleeding (2) or aspiration (1). The 5-year survival rate was 43%. Prosthetic value endocarditis caused one late death and necessitated one reoperation. If eradication of postoperative mediastinitis is not achieved by early diagnosis, debridement and closed irrigation, transposition of muscle or omentum should be considered.

Recent experience with major sternal wound complications

During a recent 1-year period, 31 patients sustained a major sternal wound infection and sternal dehiscence developed in 6 patients. Multiple potential risk factors were tabulated in these patients and in a control group selected from 1,521 patients undergoing sternotomy during the same time period. The overall infection rate was 2.1%, and the mortality rate in the patients with sternal infection or dehiscence was 16.2%. Chronic obstructive pulmonary disease, prolonged intensive care unit stay, respiratory failure, connective tissue disease, and male sex were significantly higher in the group with sternal infection or dehiscence (p less than 0.05). Advanced age and low cardiac output episodes were more frequent in this group, but only approached statistical significance. Although several risk factors may have been interrelated, male sex and the presence of pulmonary disease were statistically independent predictors of sternal wound infection. Risk factors may be helpful in identifying high-risk patients for additional prophylactic measures.

The danger in skin grafting the bare mediastinum after sternectomy for postcoronary bypass dehiscence

We describe a patient who underwent coronary bypass grafting, after which severe mediastinitis and sternal osteomyelitis occurred. Repair after sternectomy was undertaken with a rectus-abdominis myocutaneous flap. The distal fifth of the flap underwent necrosis and was replaced by a meshed split-thickness skin graft. A year later, a clip marking one of the bypass grafts nearly eroded through the skin graft, endangering the bypass graft. The skin graft was removed by abrasion, and the bypass graft was covered with a pectoralis muscle flap. We recommend that skin grafting of a granulating wound over coronary artery bypass grafts be avoided if possible.