Anaerobic mediastinitis complicating median sternotomy

Two cases of mediastinitis and bacteremia caused by Bacteroides species following median sternotomy are described. In both patients, purulent sternal drainage and signs of systemic toxicity led to the diagnosis. Surgical reexploration and administration of appropriate antibiotics effected clinical cure. Although there is only a single previous case of anaerobic mediastinitis following median sternotomy incision reported, these two cases suggest that this unusual infection may not be so rare as previously thought.     

Sternotomy infections with Mycoplasma hominis

Mycoplasma hominis caused sternal wound infections with mediastinitis in three patients. One infection occurred in a nonimmunocompromised man after coronary artery bypass grafting. The wound did not heal after repeated debridement, closed irrigation of the mediastinum with povidone-iodine solution, and antimycoplasmal chemotherapy; muscle flap grafting was eventually required. Two infections occurred in recipients of heart-lung transplants after the isolation of mycoplasma from bronchial secretions. Although no Mycoplasma species were isolated after specific antimycoplasmal therapy was begun, the wounds still did not heal. Both patients died of other complications. Infection of wounds after sternotomy is another of an increasing number of infections caused by M. hominis in the normal and immunocompromised host. Familiarity with the morphologic characteristics of M. hominis on bacteriologic culture media may increase the recognition of this pathogen in atypical clinical settings.     

Median sternotomy wound infection and anterior mediastinitis caused by bacteroides fragilis.

The first reported case of median sternotomy infection and mediastinitis caused by Bacteroides fragilis is described. Several positive blood cultures led to diagnostic anaerobic cultures of the wound and administration of clindamycin therapy. This anaerobic infection should be suspected whenever Gram smears of exudates show gram-negative bacilli and aerobic cultures are sterile.     

Life-threatening Mycoplasma hominis mediastinitis.

Mycoplasma hominis infections are easily missed because conventional methods for bacterial detection may fail. Here, 8 cases of septic mediastinitis due to M. hominis are reported and reviewed in the context of previously reported cases of mediastinitis, sternum wound infection, pleuritis, or pericarditis caused by M. hominis. All 8 patients had a predisposing initial condition related to poor cardiorespiratory function, aspiration, or complications related to coronary artery surgery or other thoracic surgeries. Mediastinitis was associated with purulent pleural effusion and acute septic symptoms requiring inotropic medication and ventilatory support. Later, the patients had a tendency for indolent chronic courses with pleuritis, pericarditis, or open sternal wounds that lasted for several months. M. hominis infections may also present as mild sternum wound infection or as chronic local pericarditis or pleuritis without septic mediastinitis. Treatment includes surgical drainage and debridement. Antibiotics effective against M. hominis should be considered when treating mediastinitis of unknown etiology.     

Awake off- pump coronary artery bypass surgery in 25 patients

Objectives To test the feasibility of the use of high thoracic epidural anesthesia as a sole anesthetic in patients undergoing off pump coronary artery bypass surgery, avoiding general anesthesia. Methods Between October 2002 to April 2003, twenty five cases underwent beating heart coronary artery revascularization without endotracheal general anesthesia, using high thoracic epidural anesthesia and analgesia. All the patients underwent epidural catheterization on the evening before the surgery. Resuits The patients in all received 71 grafts (single n= 11, double n = 5, triple n = 6, quadruple n =3). Six patients underwent repeat coronary artery bypass. Except one was converted to general anesthesia and cardiopulmonary bypass, the other patients underwent off- pump coronary artery bypass graft surgery, 2 patients underwent grafting via left thoracotomy (MIDCAB) and the rest through mid sternotomy. There was no mortality. Mean length of stay in the intensive care unit was 16 . 2 ( 4.2 hours and hospital was 3.0(1.2 days. Conclusions Our experience confirms the feasibility of performing muhiple coronary artery bypasses in conscious patients without endotracheal general anesthesia.     

Reinforced sternal closure: the bilateral straight longitudinal wire technique

Sternal dehiscence and mediastinitis are among the most severe complications of median sternotomy. A simplified technique of reinforced closure is described. A straight wire is inserted longitudinally on each side of the sternum, placed within the transverse wires when the latter are approximated. Using this technique in 112 patients with a precarious sternum, no cases of sternal dehiscence or mediastinitis have been seen.     

The preferred approach for mitral valve surgery after CABG: right thoracotomy, hypothermia and avoidance of LIMA-LAD graft

BACKGROUND AND AIM OF THE STUDY: An alternative to avoid redo sternotomy in patients with patent left internal mammary artery-left anterior descending coronary artery (LIMA-LAD) grafts undergoing mitral valve surgery is right thoracotomy with moderate-deep hypothermia (approximately 20 degrees C) and fibrillatory arrest without aortic cross-clamping. Few reports exist which directly compare re-sternotomy and right thoracotomy. METHODS: Between July 1992 and February 2000, 47 patients (39 males, eight females; median age 66 years; range: 41-83 years; 41 in NYHA class III or IV) with patent LIMA-LAD grafts underwent mitral valve surgery. Thirty-seven patients were approached through a right thoracotomy with moderate-deep hypothermia (median 20 degrees C) and fibrillatory arrest (right thoracotomy group), and 10 were approached through a re-sternotomy, with aortic cross-clamping and cardioplegic arrest. The median ejection fraction was 42% (range: 20-71%). Univariate analysis was used to determine predictors of outcome, as well as to evaluate differences in characteristics between groups. RESULTS: Operative mortality (OM) and perioperative myocardial infarction for the entire cohort was 11% and 10%, respectively, and there were no inter-group differences. No preoperative characteristics were associated with OM. Two LIMA-LAD graft injuries occurred in the re-sternotomy group compared with none in the right thoracotomy group (20% versus 0%, p = 0.04). Transfusion requirements were also greater in the redo sternotomy group (median 7 versus 2 packed red blood cell units, p = 0.04). CONCLUSION: Right thoracotomy with moderate-deep hypothermia and fibrillatory arrest is the preferred approach for reoperative mitral valve surgery after coronary artery bypass grafting in the presence of patent LIMA-LAD grafts. These data suggest that this approach is associated with decreased incidence of LIMA-LAD graft injury, as well as reduced transfusion requirements.     

A retrospective analysis of deep sternal wound infections after longitudinal median sternotomy

Median sternotomy is the most commonly performed surgical procedure in the treatment of heart conditions in both adults and children. Deep sternal wound infections (DSWI) present a serious complication occurring after surgery, highly demanding both of patients and surgery departments. The present study is a retrospective analysis of 9110 patients who underwent a cardiac surgery at the Center of Cardiovascular Surgery and Transplantations, Brno, Czech Republic, in the years 2005–12, and as its objective it has a definition of risk factors of DSWI after median sternotomy.In this study, a multivariate analysis found sepsis to be the most serious risk factor, in addition to harvesting of the mammary artery (to be used as a graft for revascularisation), haemodynamic instability, reintubation and male sex.     

Is hyperamylasemia after cardiac surgery due to cardiopulmonary bypass?

Although hyperamylasemia has been reported in a large proportion of patients undergoing cardiac surgery with cardiopulmonary bypass, its clinical significance and pathogenetic mechanisms remain poorly understood. The study was designed to investigate whether avoidance of cardiopulmonary bypass would limit amylase elevation. Serum levels of amylase and lipase were measured preoperatively as well as 24 and 48 hours postoperatively in 58 patients undergoing elective coronary artery bypass grafting. Three surgical approaches were used: cardiopulmonary bypass (n = 32) and off-pump through a median sternotomy (n = 14) or a left minithoracotomy (n = 12). There was no hospital mortality or postoperative abdominal complications. Transient hyperamylasemia occurred in 14 patients: 7 (22%), 5 (36%), and 2 (17%) in the respective groups. The increase in amylase levels was similar among the groups. However, no lipase elevation was detected in any patient. There was no clear correlation between hyperamylasemia and increased creatinine levels. Perioperative plasma calcium levels were normal in patients who had hyperamylasemia. Our results indicate that hyperamylasemia after bypass surgery is not related to the use of cardiopulmonary bypass or the mode of surgical access.     

Infection following coronary artery surgery. Comparison of two antibiotic prophylaxis regimens

A prospective randomized study was conducted in 200 patients undergoing coronary artery bypass surgery. All patients received intravenous (IV) cephalothin prophylaxis for 48 hours beginning with anesthetic induction. Group A (99 eligible patients) received cephalexin 500 mg po, qid for three extra days. Group B (94 eligible patients) received no oral therapy. The overall infection rate was 9.3 percent (18 patients). Six patients had multiple sites of involvement. There was no difference between group A (9.0 percent, nine patients) vs B (9.5 percent, nine patients) (p greater than 0.5). The median sternotomy infection rate, superficial or deep, was 2.6% (five patients). The surgical wound infection rate was 4.7 percent (nine patients). The overall infection rate compares favorably with that of high risk groups for clean surgical procedures defined in SENIC study. There was no advantage to prolonged oral cephalexin prophylaxis following coronary artery bypass (CAB) surgery.     

Mediastinitis after cardiac surgery in Madani Heart Center, Tabriz, Iran

Post-sternotomy infections are a kind of nosocomial infection involving the mediastinum space and the sternum, with a high morbidity and mortality rate. The present study was carried out to identify the incidence of mediastinitis following cardiac surgery and the most common risk factors. Cardic patients undergoing surgery were studied for suspicious mediastinitis infection at the Madani Heart Center, Tabriz, Iran from 2004 to 2006. The most common isolated agents included the coagulase-negative staphylococci, Staphylococcus aureus, Pseudomonas aeruginosa and Enterobacter spp. Incidence of postoperative mediastinitis after cardiac surgery was 1.2%. The mortality rate of postoperative mediastinitis was high (34.3%). Wound infection, especially mediastinitis following cardiac surgery, is rare but could be life-threatening. The most important step in the management of wound infections is prevention, and preventive measures could be strengthened by identifying the risk factors.     

Koronarchirurgie bei Diabetes mellitus

Patients with coronary artery disease (CAD) and diabetes mellitus have an increased risk of mortality when undergoing either interventional or surgical revascularization. However, the rate of necessary reinterventions is significantly lower after surgical revascularization than after percutaneous transluminal coronary angioplasty (PTCA). As yet, no results of long-term follow-up after stent implantation are available. The risk for a patient with diabetes mellitus and CAD of dying of myocardial infarction after a bypass operation is significantly lower than after PTCA. Bypass operation with sternotomy in patients with diabetes mellitus carries, however, an increased risk of postoperative mediastinitis, especially when both internal thoracic arteries are used for "totally arterial" revascularization. For this reason the internal thoracic artery should be used only unilaterally in surgical revascularization in these patients. Preoperative and postoperative stabilization of the blood sugar level is very important. Sclerosis of the vessels in close proximity to the heart (ascending aorta, carotid arteries) must be clarified preoperatively. The operation should be carried out particularly carefully, with the wound area kept as small as possible. Reexploration should definitely be avoided. If these guidelines are followed, surgical revascularization in patients with CAD and diabetes mellitus can achieve very good results.     

Robotically enhanced coronary artery bypass surgery

BACKGROUND: Robotically enhanced telemanipulation surgery is a fast developing technique which allows totally endoscopic cardiac surgery with utmost precision and perfection on both beating heart as well as arrested heart. METHODS AND RESULTS: Between December 2002 and February 2004, 125 patients underwent robotically enhanced coronary artery bypass surgery using the da Vinci telemanipulation system (Intuitive Surgical Inc., California). Eleven patients underwent totally endoscopic coronary artery bypass surgery. Of them 9 were done on beating heart while 2 were done on arrested heart. One hundred and fourteen patients had endoscopic takedown of internal mammary artery followed by minimally invasive direct coronary artery bypass in 63 patients and left anterolateral thoracotomy in 51 patients. The internal mammary artery mobilization time was 42 min (35-74 min) while the left internal mammary artery to left anterior descending artery anastomosis time ranged from 20 to 36 min for the totally endoscopic coronary artery bypass patients. In 1 patient, the right internal mammary artery was anastomosed to diagonal artery totally endoscopically. The mean internal mammary artery flow by Doppler measurement done in patients undergoing minimally invasive direct coronary artery bypass was 64 ml/min. Seven patients required conversion to median sternotomy and coronary bypass surgery on beating heart. The mean intensive care unit stay was 1.2 days and the mean hospital stay 4.5 days. There was 1 in-hospital mortality. All 11 patients who underwent totally endoscopic bypass surgery had coronary angiography done at 3 months interval which showed 100% patency in 10 patients while one patient had 50% anastomotic narrowing for which coronary angioplasty was done in the same sitting. CONCLUSIONS: Using telematic technology, a complete endoscopic anastomosis is possible in both single vessel and suitable double vessel disease patients. The use of robotics is now extended to achieve complete myocardial revascularization by harvesting both the internal mammary arteries and making a small thoracotomy for direct anastomosis as well.     

Clinical characteristics of anaerobic bactibilia.

During a two-year period, 1,892 patients underwent biliary tract surgery at the Mayo Clinic. Both aerobic and anaerobic bile cultures were performed in 371 patients and 253 of these were positive. Anaerobes were isolated from 100 patients, although only twice in pure culture. Only aerobes grew from cultures from 153 patients. One hundred cases of biliary tract infections involving anaerobes and an equal number involving aerobes only were reviewed in order to determine their clinical characteristics. Prominent features of anaerobic bactibilia included (1) a history of complex, multiple, biliary tract surgeries often involving biliary-intestinal anastomoses and common bile duct manipulation, (2) severe symptoms, (3) high incidence of postoperative infectious complications, especially wound infections. Further analysis of anaerobic biliary infections suggested that Bacteroides fragilis was more often associated with serious pathologic conditions of the biliary tract than was Clostridium.     

Coronary artery fistula. Management and intermediate-term outcome after transcatheter coil occlusion

During the last 2 decades, transcatheter occlusion of coronary artery fistulae has developed into a safe and effective therapy for children. This procedure avoids the need for open surgical repair and the attendant complications of cardiopulmonary bypass and median sternotomy. The long-term outcome in patients after transcatheter occlusion remains unknown. We describe the intermediate-term progress of 4 such patients after coil occlusion of coronary artery fistulae. Persistent coronary artery dilatation was present in all patients reviewed, as late as 4 years after occlusion.     

Limiting pericardial adhesions after coronary artery bypass: experimental study

Retrosternal pericardial adhesion formation constitutes a major hazard during re-do coronary artery surgery. To determine whether an onlay parietal pleural flap over the internal thoracic artery bed would reduce pericardial adhesions after coronary artery grafting, 16 sheep underwent a median sternotomy and both internal thoracic arteries were harvested. On the randomly selected study side, a dissected pleural flap was used to cover the internal thoracic artery bed, the opposite side was left uncovered as a control. Half of the sheep were sacrificed at a median of 102 days (range, 93-109 days), the remainder at a median of 176 days (range, 165-183 days). Two independent observers blinded to the initial operation scored the degree of postoperative adhesions. There was a significant decrease in adhesion formation on the study side covered by the mobilized pleural flap, compared to the control side. There were no increases in pulmonary morbidity or sternotomy wound problems from raising the lateral pleural flap. This simple technique appears to be an effective method of preventing adhesion formation following coronary artery bypass grafting utilizing the internal thoracic artery.     

Off-pump surgery: a choice in unstable angina

The benefit and safety of off-pump coronary artery bypass surgery in patients with unstable angina was assessed retrospectively. From February 1996 to October 2001, 5,306 patients underwent multivessel off-pump coronary artery bypass, of whom 920 (17%) had unstable angina. In these 920 patients, ejection fractions ranged from 15% to 70%, 203 (22%) had an ejection fraction of 20%-35%, and 11 (1%) had an ejection fraction < 20%. Triple-vessel disease was present in 625 patients. Preoperative intraaortic balloon pump support was used in 28 patients. Operative approaches included mid sternotomy (86%), lower partial sternotomy (9%), and left anterior thoracotomy (2%). The number of grafts ranged from 1 to 5 with a mean of 2.43 +/- 0.86, and 92.3% of patients received a left internal mammary artery graft. Twenty-two patients need intraoperative intraaortic balloon pumping. Ten patients (1%) suffered perioperative myocardial infarction. The mean hospital stay was 7.8 +/- 4.3 days. Hospital mortality was 2/920 (0.22%). Intraaortic balloon pumping was helpful in these cases of unstable angina refractory to medical therapy. Off-pump coronary artery surgery was found to be safe and beneficial in these patients.     

Totally endoscopic coronary artery bypass surgery

Robotically enhanced surgery is a fast-developing technique that allows totally endoscopic cardiac surgery on both the beating and arrested heart. Between December 2002 and May 2005, 13 patients underwent totally endoscopic coronary bypass using the da Vinci system; 11 operations were on a beating heart and 2 on arrested hearts. The mean time for internal mammary artery mobilization was 42 min. The time for left internal mammary artery-to-left anterior descending artery anastomosis was 20-36 min for totally endoscopic cases. In one patient, the right internal mammary artery was anastomosed to the diagonal artery. No patient required conversion to a median sternotomy. Mean intensive care unit stay was 1.2 days and mean hospital stay was 4.5 days. There was no hospital mortality. All 13 patients had coronary angiography at 3-month intervals, which showed 100% patency in 12 patients while one had 50% anastomotic narrowing for which coronary angioplasty was performed. Using robotic technology, completely endoscopic anastomosis is possible in patients with single-vessel disease. Use of robotics is now extended to achieve complete myocardial revascularization by harvesting both internal mammary arteries in addition to making a small thoracotomy for direct anastomosis.     

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.     

Combined minimally invasive mitral valve repair and direct coronary artery bypass: a new alternative to sternotomy

A case is presented in which significant single-vessel coronary artery disease and severe mitral valve regurgitation were successfully managed using combined minimally invasive direct coronary artery bypass and mitral valve repair. Although the management of coronary artery disease with simultaneous mitral valve disease has traditionally been approached using a median sternotomy, this combined minimally invasive approach led to a successful outcome and may serve as an alternative methodology for patients who are appropriate candidates.