Treatment of mediastinitis in children after cardiac surgery. A study of 20 cases

Mediastinitis in pediatric cardiac surgery: treatment and cost-effectiveness in a low-income country

Mediastinitis is a serious postoperative complication following pediatric cardiac surgery. The objective of this study is to evaluate the cost-effectiveness of surgical treatment for mediastinitis in Guatemala. All children who underwent a median sternotomy and developed postoperative mediastinitis between January 2004 and December 2005 were evaluated. Type of surgical treatment for mediastinitis, hospital outcome, and costs were analyzed. Eighteen (3.3%) of the 535 children who underwent a median sternotomy developed mediastinitis. Two patients underwent debridement of the infected tissues and delayed sternal closure, whereas 16 patients had debridement, primary chest closure, and continuous antibiotic irrigation of the mediastinum. All 11 patients who had the diagnosis of mediastinitis within 2 weeks after the operation survived. Three of the 7 patients (43%) who had delayed diagnosis died (p = 0.0003); all 3 had osteomyelitis (p = 0.0007). Primary closure with antibiotic irrigation was associated to a lower mortality rate and proved less expensive in comparison to delayed sternal closure (p = 0.003) mainly due to the shorter intensive care requirement. Debridement followed by primary closure of the chest and continuous antibiotic irrigation of the mediastinum seems to be a feasible and less expensive method to treat selected cases of postoperative mediastinitis in children.

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.

An outbreak of Staphylococcus aureus in a pediatric cardiothoracic surgery unit

OBJECTIVE

To investigate an outbreak of Staphylococcus aureus surgical-site infections.

DESIGN

Case-control study.

SETTING

Pediatric cardiothoracic surgery service of a tertiary-care university medical center.

METHOD

Molecular typing was used to identify healthcare workers who carried the epidemic strain.

RESULTS

Three children acquired surgical-site infections caused by a single strain of S. aureus. Fourteen (25%) of the staff members in the operating room and 17 (11%) on nursing units carried the epidemic strain (P = .01). A case-control study identified 4 healthcare workers who were associated statistically with the outbreak, 2 of whom (a cardiothoracic surgeon and a perfusionist) carried the epidemic strain in their nares. The surgeon also carried the epidemic strain on his hands. Each staff member who carried the epidemic strain was treated with mupirocin; those carrying the strain on their hands were required to wash their hands with chlorhexidine. The surgeon was not allowed to perform surgery until 2 of his hand cultures did not grow S. aureus.

CONCLUSIONS

Only three children were infected with the epidemic strain, but it was disseminated widely among staff who cared for children who underwent cardiothoracic surgery. No additional cases were identified after staff members who carried the epidemic strain were decolonized. Both classic epidemiologic methods and molecular typing techniques were necessary to identify the source and extent of this outbreak.

Adjuvant treatment of deep sternal wound infection with collagenous gentamycin

BACKGROUND

The treatment of deep sternal wound infections remains controversial. Currently advocated procedures carry the risk of reinfections. The significance of local antibiotic-releasing systems as an adjuvant therapy to avoid reinfections is the subject of the presented study.

METHODS

Forty-two patients with deep sternal wound complication were treated with radical wound debridement, sternal refixation, retrosternal suction drainage, bilateral pectoralis major muscle flaps, and placement of collagenous drug carrier loaded with gentamycin (Sulmycin Implant) underneath, above, and between the sternal edges.

RESULTS

No treatment failure and death were observed in our patients. Side effects after adjuvant treatment with collagenous gentamycin were not detected.

CONCLUSIONS

The preliminary results of adjuvant therapy with collagenous gentamycin in combination with surgical debridement leads to excellent results in the treatment of early deep sternal wound infections with no death and no primary treatment failures. This technique is easy to perform, reliable, and safe. For final judgment controlled randomized trials are mandatory.

Mediastinitis due to Mycobacterium fortuitum infection following Fontan operation in a child

Here we report a case of mediastinitis due to Mycobacterium fortuitum infection in a child after a Fontan operation. To our knowledge this is the first report of atypical mycobacterial mediastinal infection after congenital heart surgery. Atypical mycobacteria can be the cause of "culture negative" sternal and thoracotomy wound infections. A brief review of the literature is included in the discussion.

Closed drainage using Redon catheters for local treatment of poststernotomy mediastinitis

BACKGROUND

Continuous irrigation has been used worldwide for the treatment of acute poststernotomy mediastinitis. However, its high rate of failure led to the development of new methods, among them closed drainage with Redon catheters.

METHODS

We evaluated the results obtained with Redon catheters in 70 patients, and compared them to those obtained in 38 patients treated with continuous irrigation.

RESULTS

The two treatment groups were not different for age, type of cardiac operation, and initial severity of illness. Local failure of Redon catheter drainage occurred less frequently (20 of 38 versus 9 of 70 patients; p = 0.0001). This reduced failure rate was mainly attributable to a lower incidence of superinfections (10 of 38 versus 2 of 70 patients; p = 0.0002), but also to a lower incidence of primary failure (10 of 38 versus 7 of 70 patients; p = 0.026). Mortality was significantly decreased (15 of 38 versus 12 of 70 patients; p = 0.01). The other major advantage of this technique was the simplicity of its use.

CONCLUSIONS

The technique using Redon catheters should be considered an effective and convenient treatment of acute poststernotomy mediastinitis.

Profuse mediastinal haemorrhage due to mediastinitis after sternotomy. Report of three cases and review of the literature

Profuse spontaneous haemorrhage occurred in association with mediastinitis after median sternotomy for coronary bypass surgery in three men aged 54, 47 and 59 years. The bleeding sites were aorta, right ventricle and saphenous bypass graft. The aortic rupture occurred during closed lavage, the right ventricle ruptured during open saline mediastinal packing and the saphenous vein graft was eroded by a mediastinal drainage tube after discontinuation of closed lavage. This third patient survived and recovered, but the two others died. Previously published reports of 56 patients with 65 bleedings from this rare complication are reviewed. The outcome was fatal in 34% of cases.

Single-stage treatment of sternal wound complications in heart transplant recipients in whom pectoralis major myocutaneous advancement flaps were used

Treatment of sternal wound complications is controversial, particularly in immunosuppressed heart transplant recipients. Regardless of the severity of infection, we combine immediate, aggressive débridement with bilateral pectoralis major myocutaneous advancement flaps in a single procedure. Compared with management with pectoralis major turnover flaps or distant pedicled muscle flaps, treatment of these sternal wounds with pectoralis major myocutaneous advancement flaps is simpler and quicker and provides better aesthetic results. Furthermore, because pectoralis major myocutaneous flaps are based on the thoracoacromial arteries, whether or not the internal mammary arteries have previously been harvested for coronary grafts is irrelevant. Twenty consecutive heart transplant recipients with sternal wound complications were treated with this technique. No intraoperative or perioperative deaths occurred. The morbidity rate was 30%, with seroma treated by needle aspiration in four patients (20%) being the most common complication. Only one patient had a postoperative wound infection. All patients had excellent functional and aesthetic results.

Iodine toxicity secondary to continuous povidone-iodine mediastinal irrigation in dogs

Mediastinitis is a devastating complication following median sternotomy. Continuous povidone-iodine (PVP-I) irrigation has been advocated as therapy because of its broad antimicrobial spectrum and its apparent safety. However, several recent clinical reports have warned of suspected local and systemic iodine toxicity. The purpose of this study is to determine if significant amounts of iodine can be absorbed systemically via the mediastinum, and if so, what toxicity (local and/or systemic) may result. PVP-I (0.5%) was continuously irrigated into the pericardial sacs of three dogs via catheters for 48 hr. Serial serum and urine iodine levels were determined. The serum steady-state concentration (Css), the rate elimination constant (k), the urinary clearance (Cl), and the serum half-life (t 1/2) for iodine were assessed. Serum electrolytes, Bun, Cr, and arterial pH were measured to assess systemic iodine toxicity. Tissue samples of the heart, pericardium, liver, and kidney were examined histologically for evidence of local or end-organ iodine toxicity. This study demonstrated that the absorption of iodine during continuous mediastinal irrigation with PVP-I follows zero-order pharmacokinetics, just as if it were being given by continuous intravenous infusion. The baseline serum iodine concentration was 145.9 +/- 64.3 micrograms/dl, Css was 29,290 +/- 101.4 micrograms/dl, k was 0.0996 +/- 0.009/hr, Cl was 872.4 +/- 119.3 ml/hr, and t1/2 was 6.22 hr. Urinary excretion of iodine increased in proportion to the serum iodine. Measured serum chloride increased in a linear manner (r = 0.949), while serum Na, K, Bun, Cr, and pH were unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute mediastinitis. What to do when the cause is nonsurgical

Acute mediastinitis is a serious disease that requires prompt diagnosis and aggressive treatment. In each case, treatment should be individualized to the clinical presentation and suspected cause. The authors presented a general therapeutic scheme that may be used in the initial management of patients with acute mediastinitis from nonsurgical sources.

Candida mediastinitis after a cardiac operation

Candida mediastinitis is a rare condition characterized by a high mortality and chronic morbidity, Including the present review, only 39 cases have been described, 67% occurring after a cardiac operation. Candida mediastinitis has a 55% mortality in the postoperative setting and a mortality of 92% among patients without a prior cardiac procedure. Although no patient survived Candida mediastinitis without surgical drainage of the mediastinum, survival was 85% among 13 patients who underwent operative mediastinal drainage. Chronic wound infection developed in 6 survivors of operative drainage without muscle flap closure, but in all patients closed with vascularized flaps, healing ultimately occurred. Aggressive surgical management with mediastinal drainage, sternal debridement, and early wound closure with vascularized flaps are essential to minimize the otherwise high morbidity and mortality of Candida mediastinitis.

Delayed primary closure after sternal wound infection

Infected median sternotomy is a major complication of cardiac operations. Over a 30-month period, 25 sternal wound infections were treated at a single institution. Twenty-four (2.7%) followed 883 operations with cardiopulmonary bypass, and 1 followed median sternotomy for a noncardiac procedure. Twenty-one of the 25 patients survived to sternal closure. Eighteen patients were treated with delayed primary closure and 3 with pectoralis muscle flaps. Fifteen patients (83%) had an uneventful postoperative course after delayed primary closure. In 2 patients reoperation was required for sternal dehiscence, and in 1 patient a superficial wound infection developed, which was treated with local wound care. In all 18 patients the sternum eventually healed. Criteria for delayed primary closure included clean tissue surfaces without purulent debris, the absence of pockets of purulent drainage, and negative wound cultures obtained 24 hours before closure. The average time from operation to sternal incision and drainage was 11 days (range, five to 59 days). Delayed primary closure was performed nine days after incision and drainage (range, five to 27 days). The average hospital stay was 24 days after sternal incision and drainage (range, nine to 85 days). Cultures from specimens taken at the time of sternal incision and drainage were positive in all patients. Wound cultures were positive at the time of sternal closure in 5 patients. Wound complications developed in 2 of these 5 patients. Delayed primary closure has many of the advantages of classic methods, but fewer complications. Results are comparable, while allowing simpler wound care and less cosmetic deformity. Delayed primary closure is an acceptable alternative in the treatment of sternal wound infections.

Suppurative mediastinitis after open heart surgery. A case control study of risk factors

Suppurative mediastinitis occurred in 68 of 9,965 patients (0.7 percent) who underwent median sternotomy at Emory University Hospital from 1973 through 1982. Case-control methodology was used to identify preoperative, intraoperative, and postoperative risk factors for the development of poststernotomy mediastinitis. The following 12 individually significant risk factors were identified by univariate analysis: preoperative factors: history of chronic obstructive pulmonary disease (COPD), history of prior sternotomy, pyuria, low ejection fraction, and high left ventricular end-diastolic pressure; intraoperative factors: valvular or aortic aneurysm surgery, prolonged bypass pump time, repeat placement on bypass, duration of surgery; and postoperative factors: surgical reexploration due to postoperative hemorrhage, cardiopulmonary resuscitation in the immediate postoperative period, prolonged time (greater than 48 hours) on mechanical ventilation. By logistic regression analysis, three of these factors were found to be associated independently with increased odds of developing mediastinitis: duration of surgery, history of COPD, and prolonged postoperative mechanical ventilation.

Management of postoperative mediastinitis in infants and children by muscle flap rotation

Between July 1, 1976, and June 30, 1986, at the Henrietta Egleston Hospital for Children, 2,242 infants and children underwent palliation or repair of a congenital heart defect. Twenty-one (0.94%) of these patients developed mediastinitis following a median sternotomy. Nineteen of these twenty-one patients had required cardiopulmonary bypass. All patients had positive mediastinal cultures. The first 8 patients were managed traditionally by debridement and irrigation. Three of these patients suffered serious metabolic complications related to the povidone-iodine irrigant, which resulted in 1 death. Another patient died from persistent sepsis following debridement. Subsequently, 13 patients were managed by early debridement and rotation of the pectoralis major or rectus abdominis muscle flaps, or both. Following muscle flap rotation and early wound closure, 2 patients had subsequent incisional complications. One patient had incisional dehiscence and 1 had a superficial skin separation. Two deaths in this group, 28 and 51 days, respectively, following muscle flap rotation, resulted from nonincisional problems in patients with healed median sternotomies. The group having muscle flap rotation required a significantly shorter duration of postoperative ventilatory support (3.2 versus 24 days, p less than 0.05) and a significantly shorter confinement in the intensive care unit (6.2 versus 33 days, p less than 0.01). Also, the physiological and physical trauma of continued wound care in the awake child was minimized in the group with muscle flap rotation.

Major sternal wound infection after open-heart surgery: a multivariate analysis of risk factors in 2,579 consecutive operative procedures

From January, 1979, to December, 1984, at the Cardiac Surgery Department of the University of Torino Medical School, major sternal wound infections developed in 48 (1.86%) of 2,579 consecutive patients. These patients underwent open-heart procedures through a midline sternotomy and survived long enough for infection to appear. Possible risk factors were evaluated by means of a multivariate analysis. For the group of patients, we considered age, sex, hospital environment (different locations of our surgical facilities over the years), interval between hospital admission and operation, antibiotic prophylaxis, type of surgical procedure, elective or emergency surgical procedure, reoperation, duration of surgical procedures, duration of cardiopulmonary bypass, amount of blood transfused, postoperative blood loss, chest reexploration, rewiring of a sterile sternal dehiscence, duration of mechanical ventilation, and days of treatment in the intensive care unit. Univariate analysis indicated that age, sex, type and mode of surgical procedure, antibiotic prophylaxis, and duration of mechanical ventilation were not significantly associated with wound infection. For all other predisposing factors, a p value of less than .05 was demonstrated. These variables were entered in a multiple stepwise logistic regression. Six emerged as significant: hospital environment (p = .0001), interval between admission and surgery (p = .041), reoperation (p less than .0001), blood transfusions (p = .031), early chest reexploration (p less than .0001), and sternal rewiring (p less than .0001). Contamination of patients may occur before, during, and after operation, and any kind of reintervention may predispose to wound infection.

Use of granulated sugar in treatment of open mediastinitis after cardiac surgery

19 critically ill adults with acute mediastinitis after cardiac surgery were treated with granulated sugar, either directly (11 patients) or after failure of continuous irrigation (8 patients). Mediastinal tissue cultures were positive in 18 patients. Packing the mediastinal cavity with granulated sugar every 3 or 4 h resulted in near-complete debridement of the wound and rapid formation of granulation tissue in all patients and sterilisation of the wound after an average of 7.6 days. Dressings were easy and painless to change. 5/19 (26%) patients died before discharge, but none because of wound complications. The rest were discharged on average 54.2 days (range 29-120) after initial debridement of the wound; 11 underwent secondary surgical closure of the wound and in 3 the wound healed by granulation tissue formation alone. No recurrence of sternal infection has occurred after a mean follow-up of 8.2 months (range 3 to 17).

Mediastinal infection after cardiac surgery

Mediastinitis is an uncommon complication after cardiac surgery; however, its associated morbidity and mortality demand early recognition and emergency therapy. This review is intended to emphasize certain features of the incidence, pathogenesis, and bacteriology of this complication in patients undergoing cardiopulmonary bypass through a median sternotomy. The diagnosis and treatment of mediastinitis after cardiac surgical procedures, as well as methods of prevention, are also reviewed.