Surgical considerations in patients undergoing repeat median sternotomy

Surgical considerations in patients undergoing repeat median sternotomy A retrospective review of 122 repeat median sternotomy incisions in 100 consecutive patients was made to evaluate complications and management. Eighty-one patients had one repeat sternotomy, 16 had two repeat sternotomies, and 3 had three repeat sternotomies. All had valve procedures in the past and were reoperated upon for progressive rheumatic valvular disease or for complications related to the prostheses. Complications included operative hemorrhage in 8 patients, postoperative hemorrhage in 2, seroma in 4, and dehiscence, wound infection, and hematoma in 1 patient each. The most serious complication was hemorrhage and was the cause of the only operative death. Seven other patients survived hemorrhage encountered during repeat sternotomy. Control of massive hemorrhage during repeat sternotomy has been possible due to an organized approach to the patient with adhesions from previous surgery.

Quentin Macmanus, J. Edward Okies, Steven J. Phillips, and Albert Starr, Portland, Ore.

V,

alve repair and prosthetic valve replacement have resulted in marked improvement in the functional status of many patients with valvular heart disease. Progression of disease in repaired or untreated valves, as well as prosthesis-related complications, has necessitated reoperation in some of these individuals. This select group of patients has an inherent risk of massive hemorrhage during reoperation, in addition to the risks of morbidity and death attendant with progressive myocardial dysfunction. This report concerns the evaluation of 100 consecutive patients undergoing repeat median sternotomy incisions for valve repair(s) or replacement(s). Particular reference is given to the technical factors important in the prevention and management of massive hemorrhage. Clinical material One hundred consecutive patients with previous median sternotomy incision underFrom the Department of Cardiopulmonary Surgery, 3181 S. W. Sam Jackson Park Road, Portland, Ore. 97201. Received for publication June 14, 1974. Address reprint requests to Dr. Albert Starr.

1 38

went 122 repeat sternotomies from 1957 through August, 1973, at the University of Oregon Medical School Hospital. There were 54 male and 46 female subjects, ranging in age from 10 to 70 years at the time of initial repeat sternotomy. Indications for reoperation were progressive valvular heart disease and/or complications related to the prostheses. Patients undergoing immediate repeat sternotomy for bleeding (14 patients) or progressive low cardiac output syndrome (2 patients) were excluded from this report. One repeat sternotomy was performed in 81 patients, two repeat sternotomies in 16 patients, and three repeat sternotomies in 3 patients. The operative procedures have been categorized in Table I. A lateral chest roentgenogram was often useful in predetermining the likelihood and the extent of adhesions between the heart and great vessels and the sternum. A posterior paddle (internal-external) was routinely placed behind each patient so that defibrillation could be accomplished easily without extensive dissection of the heart. A venous line was inserted into the superior

Volume 69

13 9

Repeat median sternotomy

Number 1 January, 1975

Table I. Operative procedures in 100 consecutive patients undergoing repeat sternotomy Operation Single valve replacement Double valve replacement Triple valve replacement Single valvuloplasty Double valvuloplasty Other double-valve procedures Other triple-valve procedures Suture periprosthetic leak Miscellaneous No. of patients

Initial sternotomy 50 17 6 10 1 7 1 0 8 100

vena cava and two large-bore venous lines were available for fluid and drug administration through the arm veins in every case. Blood pumps were inflated for immediate use. Blood pressure was monitored with a Doppler* flow detector. Platelet concentrates and fresh-frozen plasma were available for use postoperatively. No other special precautions were taken with patients undergoing repeat sternotomy. Technique Preparations for institution of femorofemoral bypass are made in every case because of the possibility of inadvertent entry into the heart or great vessels when the sternum is divided. Both groins are prepared and draped into the surgical field. The arterial line is cut so that it is able to reach a cannula inserted into the femoral artery or distal ascending aorta. A length of plastic tubing is connected to one limb of the venous Y connector and clamped. A single venous cannula can be inserted into the femoral vein and connected to the other limb of the Y connector, and the patient thus can be placed on partial bypass. A second catheter may subsequently be inserted through the right atrium into the superior vena cava after hemorrhage is controlled (Fig. 1). After the skin incision has been reopened, sternal wires or Teflon-impregnated Dacron *Parks Electronics Lab., Beaverton, Ore.

First repeal sternotomy

Second repeat sternotomy

Third repeat sternotomy

66 10 3 1 0 4 1 6 9 100

15 1 0 0 0 0 0 2 1

2 1 0 0 0 0 0 0 0

19

3

sutures are divided but not removed, so that the blade of the sternal saw has something to abut against. An attempt is made to manipulate a finger around the manubrium and xiphoid sternum into the retrosternal space to palpate and in many instances bluntly separate the heart and great vessels from the sternum. Heavy scissors may be used to cut through the xiphoid to facilitate this maneuver. Inability to insert a finger alerts the surgeon to the likelihood of injury to the heart or great vessels when the sternum is divided. The heart can often be separated from the lower sternum by sharp dissection, which is facilitated by retracting and elevating the linea alba and xyphisternum. If this proves too difficult, partial bypass with hypothermia can be initiated in the groin before proceeding. A vibrating Stryker saw is then utilized to divide the sternum beginning at the manubrium. Extreme caution is exercised to extend the cut just into or slightly beyond the posterior table of the sternum. Once the sternum has been divided longitudinally, an army-navy retractor is inserted between the cut ends of the sternum and rotated. A heavy scissors or knife is then utilized to cut the remaining posterior sternal wall and/or adhesions. Sternal sutures can then be removed. Rakes are placed on one side of the sternum and then the other, and gentle retraction is provided while the surgeon sharply dissects cardiac adhesions. One blade of a scissors can often be inserted

The Journal of

14 0

Macmanus et al.

Thoracic and Cardiovascular Surgery

Table II. Complications in 100 consecutive patients undergoing repeat sternotomy Complication Hemorrhage related to opening sternum Hemorrhage related to closing sternum (internal mammary artery injury) Wound seroma or hematoma Wound infection Sternal dehiscence No. of patients

Primary sternotomy

Repeat sternotomy

1

8

0

2

4 0 3 8

5 1 1 17

lateral to the scar, which can then be easily divided. Adhesions are usually limited to the site of previous sternotomy, and the dissection proceeds rapidly after the scar tissue in this area is divided. The pleural spaces are commonly entered and should be drained with tubes before closure. After adhesions have been divided, skin towels are placed, a chest retractor is inserted, and the sternum is carefully separated. Remaining fibrous adhesions can be cut as they are encountered to prevent tearing of the heart as the sternum is separated. A relatively free plane of dissection is usually found at the diaphragmatic surface of the heart. Breaking into adhesions in this

area allows both blunt and sharp dissection to proceed rapidly in a transverse direction. Remnant of pericardium can be found laterally, and the dissection can be extended cephalad along the right and left cardiac borders with separation of the remaining pericardium or lung tissue from the heart. Densely adherent pericardium over the right atrium may be left in place to avoid tearing during dissection. If the dissection is difficult, the innominate vein can be identified and the base of the heart dissected from above. The pericardium is suspended from the skin towels for improved exposure. The aorta is separated from the pericardium, thymic fat, and pulmonary artery, and an umbilical tape is passed about it for traction, control, and exposure. If the plane between the aorta and the pulmonary artery is obliterated and the aorta need not be opened, dissection is abandoned, because ischemic arrest may be obtained when necessary by crossclamping both vessels together. Extreme caution should be exercised during this maneuver, however, to avoid injury to the right pulmonary artery beneath the aorta. The patient can then be systemically heparinized and cannulated in the routine fashion and bypass instituted. The need for dissection of the heart varies with the procedure. Whereas tricuspid valve surgery requires little cardiac mobilization, mitral valve surgery is markedly simplified by freeing the apex to allow improved exposure. Venting of the left heart may be accomplished through the right superior pulmonary vein or left atrium if the apex is too adherent. Bleeding encountered prior to completion of the sternotomy is controlled digitally while systemic heparinization and partial bypass through the groin are instituted. The patient is cooled to at least 30° C. The sternotomy is completed, adhesions are dissected, and bleeding sites are identified and controlled with sutures often bolstered with Teflon felt. The aorta can be cross-clamped or pump flow markedly reduced to decrease bleeding and to facilitate exposure and dissection. Coronary suction lines are utilized

Volume 69

Repeat median stemotomy

Number 1

14 1

January, 1975

Table III. Management of profuse hemorrhage complicating repeat in 8 patients Initial procedure

Indications for reoperation

Subsequent procedure

Periprosthetic leak Suture periprosthetic leak AVR Prosthetic throm- Emergency exploration of aorbosis tic prosthesis Tricuspid insufTVR MVR ficiency Silicone poppet AVR Ball variance, change, wrapascending aortic ping of ascendaneurysm ing aortic aneurysm AVR MVR, AVR, Aortic ball variance TVR MVR, aor- Aortic insufficien- AVR cy, tricuspid in- TVR tic comsufficiency missurotomy Aortic com- Aortic stenosis and AVR insufficiency missurotomy Ball variance AVR AVR AVR

Site of hemorrhage PA

stemotomy

Management

Aorta PA

Tamponade, partial bypass, primary suture Tamponade, partial bypass; died of hemorrhage on table

RA

Tamponade, primary suture

Aorta

Tamponade, partial bypass, primary suture with Teflon felt

RA

Tamponade, primary suture

PA

Tamponade, primary suture

RV

Tamponade, primary suture

Aorta RV RA

Tamponade, partial bypass, primary suture with Teflon felt

Legend: AVR, Aortic valve replacement. MVR, Mitral valve re placement. TVR, Tricuspid valve replacement. PA, Pulmonary artery. RA, Right atrium. RV, Right ventricle.

to prevent exsanguination. It is mandatory that the sternum not be carelessly opened, so that further damage to the heart and great vessels is avoided. Bleeding encountered during dissection of the heart and great vessels after the sternum is divided is controlled by digital pressure, followed by systemic heparinization and cannulation of the femoral artery or distal ascending aorta. Coronary suckers may be used to institute partial bypass while vena caval cannulas are inserted. Appropriately located atrial tears may be used as cannulation sites. If dissection is difficult, institution of partial or total bypass is a useful way of decompressing the heart and allowing more rapid dissection. Once the procedure is terminated, meticulous hemostasis is obtained by the use of the cautery, suture ligatures, and blood component therapy. Incisions are not closed unless bleeding has stopped. Oc-

casionally, intraoperative consultation with the hematology service is obtained to identify and correct coagulopathies. The sternums are approximated with interrupted sutures of Teflon-impregnated Dacron unless the patient is very large and has chronic lung disease. In such a case, Parham bands are used.1 These allow for secure closures and rapid re-entry in case of cardiac arrest, hemorrhage, or tamponade. Results Complications that occurred after primary stemotomy are listed in Table II. Reoperation was performed at varying intervals from the original operation. All patients had adhesions, but significant complications related to repeat stemotomy were encountered in only 17 (Table II). Closing the pericardium did not seem to affect the incidence of postoperative complications, although

The Journal of

14 2

Macmanus et al.

Thoracic and Cardiovascular Surgery

injury to the heart and aorta with the sternal saw occurred only in those patients in whom the pericardium was not closed. Massive hemorrhage from the heart or great vessels was the most serious complication encountered in repeat sternotomy. Bleeding occurred prior to completion of the sternotomy in 2 patients and during dissection of adhesions in 6 patients. Sites of hemorrhage and their management are listed in Table III. There was one operative death at the time of reoperation in this group of 100 patients. The patient who died had undergone aortic valve replacement with a Model 2310 Starr-Edwards prosthesis in October, 1970, for rheumatic heart disease with aortic insufficiency. He sustained a cardiac arrest following an episode of severe chest pain in May, 1971, and was brought to the emergency room having external cardiac massage and assisted ventilation. He was taken to the operating room where a repeat sternotomy was performed in a desperate attempt to resuscitate him. Massive hemorrhage from the aorta resulted in his death despite the use of partial bypass. The other 7 patients in whom major hemorrhage occurred survived surgery. The remaining complications of repeat sternotomy occurred in such low frequency that meaningful evaluation of those data was not possible. Discussion Milton,2 in 1897, while attempting to explore the posterior mediastinum, was one of the first to use a midline sternotomy incision. This approach was subsequently used for procedures involving the pericardium and thymus. Shumacker3 and Blalock reported its use in pulmonary valvulotomy in 1953.4 In 1957, Julian and associates5 reported a series of 31 cardiac operations employing median sternotomy and extolled its advantages, including avoidance of lung, easy access for cannulation, and rapid closure.4 Median sternotomy is now the most common surgical incision utilized in open-heart surgery. Practically every congenital and acquired cardiac lesion can be

exposed through this incision, and it remains the approach of choice for all primary and secondary valve procedures performed at the University of Oregon Medical School Hospital. Primary sternotomy is not without complications. Hehrlein and co-workers0 reported 293 sternotomies with complications in 21 (7.1 per cent), including seroma in 8, wound abcess in 6, osteomyelitis in 4, and dehiscence in 3 patients. Ochsner and associates7 reported a 2.7 per cent incidence of sternal dehiscence in 750 sternotomy incisions. Wound infection and anterior mediastinitis occurred in 4.5 per cent of 421 sternotomies in another series.s Brachial plexus palsies followed sternotomy in 5 patients, presumably due to entrapment of the plexus between the clavicle and the first rib with vigorous sternal retraction." The incidence and types of complications of initial sternotomy in our patients approximate those reported by these workers (Table

IDRepeat sternotomy has been associated with a higher incidence of morbidity and death.10 Although there was but one operative death related to bleeding during repeat sternotomy, hemorrhage was the major cause of morbidity in this series (Table II). An organized approach to the patient requiring reoperation has therefore evolved to reduce the possibility of major hemorrhage and to control it effectively when it occurs. Preparations should be made in every case for the possibility of massive hemorrhage occurring either during transection of the sternum or subsequently, as the heart is being dissected. Tamponade, obtained digitally or by releasing retraction on the cut adges of the sternum, followed by systemic heparinization and institution of partial bypass with moderate hypothermia by one of several routes, will allow control of an otherwise disastrous situation. Summary Data from 100 patients undergoing a total of 122 repeat sternotomies are presented. Seventeen per cent sustained

Volume 69

Repeat median sternotomy

Number 1

14 3

January, 1975

major complications, including hemorrhage, seroma, hematoma, infection, and dehiscence. There was one operative death due to uncontrollable hemorrhage. Principles of operative control of massive hemorrhage include tamponade, institution of bypass and moderate hypothermia after systemic heparinization, and the use of coronary suckers to prevent exsanguination. Repeat median sternotomy can be accomplished with minimal morbidity and risk of death if proper precautions are taken. An awareness of the possibility of massive hemorrhage in patients undergoing reoperation, followed by an organized approach to the control of hemorrhage should it occur, will assure the best possible result in this group of patients. We would like to thank Mr. Lou Lambert, Data Management, Cardiopulmonary Surgery, for assisting with acquisition of data. REFERENCES 1 Okies, J. E., and Phillips, S. J.: Letter to the Editor, Ann. Thorac. Surg. 17: 423, 1974. 2 Milton, A. F. (cited by Kirschner, M . ) : Tratatad de Tecnica Operatoria General y

Especial, Editorial Labor, S. A. Barcelona 4: 756, 1944. 3 Shumacker, H. B., Jr., and Lurie, P. R.: Pulmonary Valvulotomy, J.

THORAC.

SURG.

25:

173, 1953. 4 Scott, H. W., Jr.: Discussion of Shumacker and

Lurie, 3 J. THORAC. SURG. 25: 185,

1953.

5 Julian, O. C , Lopez-Belio, M., Dye, W. S., Javid, H., and Grove, W. J.: The Median Sternal Incision in Intracardiac Surgery, Surgery 42: 753, 1957. 6 Hehrlein, F. W., Hermann, H., and Kraus, J.: Complications of Median Sternotomy in Cardiovascular Surgery, J. Cardiovasc. Surg. 13: 390, 1972. 7 Ochsner, J. L., Mills, N. L., and Woolverton, W. C : Disruption and Infection of the Median Sternotomy Incision, J. Cardiovasc. Surg. 13: 394, 1972. 8 Jimenez-Martinez, M., Arguero-Sanchez, R., Perez-Alvarez, J. J., and Mina-Castaneda, P.: Anterior Mediastinitis as a Complication of Median Sternotomy Incisions, Surgery 67: 929, 1970. 9 Kirsch, M., Magee, K. R., Gago, O., Kahn, D. R., and Sloan, H.: Brachial Plexus Injury Following Median Sternotomy Incision, Ann. Thorac. Surg. 11: 315, 1971. 10 Londe, S., and Sugg, W. L.: The Challenge of Reoperation in Cardiac Surgery, Ann. Thorac. Surg. 17: 157, 1974.