ABSTRACT One hundred thirty-eight children underwent

Transcription

1 Repeat Median Stemotomy in Pediatrics: Experience in 164 Consecutive Cases Serafin Y. DeLeon, M.D., Joseph LoCicero 111, M.D., Michel N. Ilbawi, M.D., and Farouk S. Idriss, M.D. ABSTRACT One hundred thirty-eight children underwent 164 operations through repeat median sternotomy. Ages ranged from 4 months to 21 years (mean, 8.6 f 5.0 years). The technique consisted of opening the sternum with chisel and mallet, avoidance of sudden separation of sternal edges and blunt dissection, elimination of the electrocautery during lysis of adhesions, and judicious use of fresh blood and components. Several variables were analyzed comparing the initial and repeat procedures on each patient. Time from incision to bypass was an hour longer with the repeat procedure (174 f 45 minutes versus 96 f 37 minutes). Operative transfusions and postoperative bleeding (first 48 hours) were not significantly different between the two procedures. Cyanosis, however, significantly increased bleeding in both groups. There were eight injuries (5%) at reoperation. During sternal reentry in 2 patients, a tear occurred in a valved conduit coursing underneath the sternum. A right ventricular tear occurred in 1 patient while the sternal edges were being separated. Ventricular fibrillation was noted in 2 patients during lysis of adhesions with the electrocautery used early in the series. Intimal disruption occurred in two valved conduits during intraoperative manipulations. An aortic tear occurred and was repaired without cardiopulmonary bypass. There were 13 (8%) hospital deaths, all unrelated to the technique. We believe that the current approach can be a valuable alternative for surgeons dealing with repeat median sternotomy in children. Surgical management of complex congenital heart defects has progressed markedly in the past decade. A substantial number of patients who have had either palliation or correction will require a further procedure. Median sternotomy, introduced by Julian and associates [l], has been the standard approach for patients undergoing intracardiac repair of acquired and congenital heart defects. Although the approach has facilitated access to the heart and great vessels, major problems have been encountered on reopening a median sternotomy incision. Several centers [2-51 have reported their expe- From the Division of Cardiovascular-Thoracic Surgery, Children s Memorial Hospital, and the Department of Cardiothoracic Surgery, Northwestern University Medical School, Chicago, 1L. Accepted for publication Apr 10, Address reprint requests to Dr. DeLeon, Division of Cardiovascular- Thoracic Surgery, Children s Memorial Hospital, 2300 Children s Plaza, Chicago, IL rience with repeat median sternotomy in the adult population. Dobell and Jain [6] reviewed the attitude of 131 surgeons to the performance of repeat sternotomy and reported 144 severe and catastrophic hemorrhages that occurred as the sternotomy was being done. Several instruments (scissors, Lebsche knife, Sarns saw, and Hall drill) were used in opening the posterior table of the sternum. Having encountered several problems using the Lebsche knife, we have switched to the chisel and mallet in the last 7.5 years for reopening the sternum. This method, along with avoidance of sudden separation of the sternum, use of sharp dissection, elimination of the electrocautery during lysis of adhesions, and judicious use of fresh blood and components constitutes our approach in repeat median sternotomy. Since we could not find use of the chisel and mallet technique in previous reports and since, to our knowledge, no critical pediatric review exists, we analyzed our own experience with this technique for repeat median sternotomy in infants and children. Material and Methods One hundred sixty-four consecutive operations through a repeat median sternotomy were done in 138 infants and children from July, 1977, to January, 1985, at Children s Memorial Hospital in Chicago. To consider the procedure a reoperation, a previous median sternotomy must have been performed at least four weeks before the second procedure. The patients ranged from 4 months to 21 years old (mean, years). Tetralogy of Fallot (35 patients or 25%) was the most common lesion requiring reoperation, followed by transposition of the great arteries (18 or 13%), pseudotruncus (12 or 9%), aortic valve stenosis (9 or 7%), ventricular septal defect (7%), and hypoplastic right ventricle complex (7%). Other diagnoses included single ventricle (7 patients), ostium primum atrial septal defect (7), truncus arteriosus (6), complete atrioventricular canal (4), tricuspid atresia (4), total anomalous pulmonary venous drainage (4), and miscellaneous (13). The miscellaneous lesions included congenital mitral stenosis and insufficiency (2), subaortic stenosis (2), corrected transposition (2), rheumatic valvular disease (2), aortic atresia (l), tracheal stenosis (l), right atrial hemangioendothelioma (l), Ebstein s anomaly (l), and double-outlet right ventricle (1). The most common reason for reoperation in tetralogy of Fallot after repair was substantial pulmonary insufficiency from transannular patching associated with right ventricular dysfunction; 34 of 35 patients re- 184 Ann Thorac Surg 41: , Feb 1986

2 185 DeLeon et al: Repeat Median Sternotomy in Children quired insertion of a pulmonary valve [7]. Three patients also required replacement of a calcified pulmonary porcine valve. Sixteen patients who had a valved conduit inserted at initial repair (9, pseudotruncus; 5, truncus arteriosus; 2, corrected transposition) required conduit replacement for stenosis. Of the 15 patients with transposition of the great arteries who previously had undergone a Mustard procedure, 5 required reoperation for superior vena cava obstruction, 3 for subpulmonary stenosis requiring a left ventricle-main pulmonary artery valved conduit, and 3 for tricuspid insufficiency. Of the 9 patients with aortic valve stenosis, all of whom initially had valvotomy, 6 required aortic valve replacement and 3, aortic valvuloplasty. Of the 9 patients who had undergone closure of a ventricular septal defect, 5 required reoperation for aortic insufficiency. Five of the 7 patients with an ostium primum atrial septal defect repaired needed a reoperation because of the development of severe subaortic stenosis [8]. All 4 patients with repair of complete atrioventricular canal required mitral valve replacement. Other repeat procedures were for staged correction of complex lesions and repair of residual defects. Several factors were present that predispose to injury at the time of repeat median sternotomy [9]. Thirty patients (22%) had 2 or more repeat procedures. Twenty patients (14.5%) had valved conduits at the time of reoperation, and 9 (6.5%) had previous mediastinal infection. Technique The technique has evolved over the last 7.5 years. After the induction of anesthesia, an arterial catheter and two venous lines are placed. The chest, abdomen, and groin are prepared to provide an alternative access for cardiopulmonary bypass in case of serious difficulty when opening the sternum. The old sternotomy incision is reopened from the skin down to the sternum. The scar is not excised unless it is unusually wide. The linea alba below the xiphoid process is reopened (Fig 1). Finger dissection under the xiphoid and lower sternum is avoided, as the right ventricle can easily be injured with this maneuver. While the edges of the linea alba are separated with a self-retaining retractor, the outer table of the sternum is divided using a bone chisel and a mallet (Fig 2). Without lifting the sternum, the posterior table is divided in the same manner. Because the surgeon can feel the chisel going through the bone and touching the soft tissues underneath when the posterior table of the sternum is being opened, the appropriate tap on the chisel by the mallet can be applied, thereby minimizing soft tissue injury. A twisting motion of the chisel facilitates separation of the sternal edges (Fig 3). After the sternum is completely divided, two selfretaining retractors are placed to slightly separate the sternal edges. Sudden wide retraction of the sternal edges is avoided to prevent tearing of soft tissues, such as the right atrium and ventricle, underneath the sternum. By twisting the self-retaining retractors, one side of the sternum is elevated, and adhesions are taken Fig 1. The midsternotomy scar is reopened down to the sternum. The linea albu below the xiphoid process is divided. Lwaa Alba Fig 2. With a self-retaining retrnctor separating the edges of the linea albu, the outer table of the sternum is divided with chisel and mullet. down from the sternum and chest wall (Fig 4). The use of the electrocautery for lysis of adhesions between the heart and chest wall has been eliminated in the latter part of the series because of the occurrence of ventricular fibrillation. Once the sternal edges are freed from adhesions, reg-

3 186 The Annals of Thoracic Surgery Vol 41 No 2 February 1986 Fig 3. The inner table of the sternum is being divided. A twisting motion on the chisel facilitates separation of the sternum. Use of the chisel minimizes soft tissue injury. Fig 4. Two self-retaining retractors are applied on the sternul edges. Sudden wide separation of the sternul edges is avoided to prevent tearing of soft tissues underneath. Twisting the retractors elevates one side of the sternum and facilitates lysis of adhesions. ular retractors are placed. The aorta and right atrium are the first structures exposed in case immediate institution of bypass becomes necessary. From this point, the planned intracardiac procedure is performed. As in initial procedures, fresh blood and components are judiciously used at the end of cardiopulmonary bypass for volume replacement and correction of coagulation abnormalities. Results There were 13 deaths (8%) following the 164 repeat procedures, and all were unrelated to the technique of reoperation. Six deaths occurred in the operating room, all due to primary cardiac failure. Seven deaths occurred 3 to 60 days (average, 25 days) after reoperation. Four were due to primary cardiac failure, 2 to cerebral infarction, and 1 to sepsis. Eight injuries (5%) occurred during reoperation. A 15- year-old girl with corrected transposition who had a left ventricle-main pulmonary artery valved conduit inserted at 5 years of age required reoperation for conduit stenosis. The conduit was crossing underneath the sternum and became incorporated into it. A tear was made while the sternum was being opened. Partial cardiopulmonary bypass was instituted immediately through the femoral vessels, and the repeat sternotomy was completed without further incident. A conduit tear occurred in a 17-year-old boy who was also being reoperated on for stenosis of a conduit inserted for pseudotruncus when he was 10 years old. The outer table of the sternum had been divided. The inner table was being divided with the lower one-third already separated when the tear occurred. Bleeding was easily controlled with packing. Partial cardiopulmonary bypass was instituted through the femoral vessels. Two more tears occurred during completion of the sternotomy, but they were repaired without difficulty. A right ventricular tear occurred in a 4-month-old boy who was undergoing repatching of the right ventricular outflow tract for severe tetralogy of Fallot with small pulmonary arteries. The sternum had been opened, and the tear was made because of sudden separation of the sternal edges. Cannulation of the ascending aorta was accomplished, and cardiopulmonary bypass was instituted with the venous return from the right ventricular tear. Two patients with Dacron valved conduits had intimal disruption during dissection [lo]. One patient had pseudotruncus and was being reoperated on for conduit stenosis. The sternum had been opened, and the conduit was being dissected from adhesions when sudden hypoxia and hypotension occurred. Cardiopulmonary bypass was instituted immediately through the ascending aorta and right atrium, and when the conduit was opened, the intima was found disrupted, obstructing the pulmonary artery. The second patient had a single ventricle and was having reoperation for tricuspid patch disruption following a Fontan procedure. A Glenn shunt was also present. After the institution of cardiopulmonary bypass, a mass was felt inside the conduit, which was opened. The whole neointima was completely disrupted. The presence of the Glenn shunt probably prevented acute hemodynamic deterioration prior to cardiopulmonary bypass. Ventricular fibrillation developed in 2 patients during lysis of adhesions using the electrocautery. Defibrillation was difficult in 1, since it happened when the heart was barely exposed. A small aortic tear occurred in 1 patient and was repaired prior to the institution of cardiopulmonary bypass. Postoperatively, 4 of the patients undergoing repeat procedure required reoperation for bleeding and 1 for mediastinal infection. Comparison of several variables was made between the patients' initial and repeat procedures. Thus, the patients as a group served as their own control. The

4 187 DeLeon et al: Repeat Median Sternotomy in Children length of time from incision to bypass was an hour longer for repeat procedures (174? 45 minutes compared with 96 k 37 minutes for initial procedures). Bypass times were comparable: 124 & 58 minutes for initial and 143 * 63 minutes for repeat procedures. Operative transfusion rates standardized to body surface area were also similar. At the initial median sternotomy, the patients received an average of mvmz compared with mvmz at reoperation. The postoperative blood loss over 48 hours was also not significantly different: 548? 471 mum2 for initial procedures compared with mvmz for redo operations. The cyanotic patient (oxygen saturation less than 80%) bled significantly more postoperatively than the acyanotic child. At initial procedures, the former bled mvmz compared with mvmz for the latter (p < 0.01). At reoperation, the former bled 555 & 531 mvmz compared with 294? 203 mum2 for the latter (p < 0.05). Comment Early results of repeat median sternotomy in adults [2-51 have appeared discouraging because of ventricular or vascular injury, intraoperative and postoperative hemorrhage, wound seromas and infection, and sternal dehiscence. Because of problems related to reopening the sternum, Macmanus and associates [5] recommended institution of partial cardiopulmonary bypass through the femoral vessels prior to repeat sternotomy in certain instances. Culliford and Spencer [2], in a review of their experience, stated that the most common reasons for complications were lack of precise technique and insufficient attention to hemostasis. In the most recent report of Dobell and Jain [6], it is evident that repeat median sternotomy remains a major challenge to cardiac surgeons. Although we could not find mention of the use of the chisel and mallet technique in reopening the sternum, it is probably being employed by some surgeons. We found that it is a safe alternative approach that, combined with other guidelines, can minimize injuries to the heart and major vessels. Because in opening the posterior table of the sternum, the surgeon can feel the chisel going through the bone and touching the soft tissues underneath, the appropriate tap with the mallet can be applied, thereby minimizing soft tissue injury. Sudden separation of the sternal edges should be avoided, since it can easily cause laceration of the right atrium and ventricle. Sharp dissection is utilized because finger dissection underneath the sternum sometimes is followed by a gush of blood from the right cardiac chambers. The use of electrocautery is minimized, since these patients are prone to arrhythmias and ventricular fibrillation can be induced. Patients with valved conduits crossing or lying underneath the sternum, such as those with corrected transposition and Fontan operations, and certain patients with pseudotruncus are prone to conduit injury and probably should be placed on partial cardiopulmonary bypass through the femoral vessels prior to sternotomy. In most patients with right ventricle-main pulmonary artery conduits, the conduits are located underneath the left side of the sternum, which makes a repeat sternotomy usually safe. However, if the conduit is found coursing underneath the sternum while it is being divided, institution of cardiopulmonary bypass again should be considered before completing the sternotomy. In addition, manipulation of a Dacron valved conduit should be minimized prior to cardiopulmonary bypass, since the neointima can disrupt and cause acute conduit obstruction. The other predisposing factors to injuries that Dr. Loop [9] described, such as repeat sternotomies and previous mediastinal infection, were present in a significant number of our patients but did not contribute to injuries in our experience. Some groups maintain that repeat median sternotomy may be facilitated by certain maneuvers at the initial cardiac procedure. Cliff and associates [ll] showed that both serosal injury and blood are necessary to produce cardiac adhesions. Careful handling of the heart and complete evacuation of pericardial blood may reduce postoperative adhesions. Approximation of the pericardium or placement of synthetic biomaterials may also facilitate reoperation ( We loosely approximate the edges of the pericardium whenever possible at the initial procedure. We found, as did Gomes and associates (31, that cyanotic children had more postoperative bleeding, regardless of the number of previous operations. These children have increased cell volume, alteration in blood clotting factors, increased fibrinolysis, and platelet dysfunction. In summary, repeat median stemotomy is becoming more frequent in infants and children because of outgrown or malfunctioning cardiac prostheses, correction of residual defects, and staging operations for complex congenital heart lesions. The use of the chisel and mallet technique, along with certain maneuvers, can minimize the morbidity and mortality associated with repeat median sternotomy in the pediatric age group. This research was supported in part by the A. C. Buehler Foundation of Park Ridge, IL. References 1. Julian OC, Lopez-Belio M, Dye WS, et al: The median sternotomy in intracardiac surgery with extracorporeal circulation: a general evaluation of its use in heart surgery. Surgery 42:753, Culliford AT, Spencer FC: Guidelines for safely opening a previous sternotomy incision. J Thorac Cardiovasc Surg 78:633, Gomes MMR, McGoon DC: Bleeding patterns after openheart surgery. J Thorac Cardiovasc Surg 60237, Londe S, Sugg WL: The challenge of reoperation in cardiac surgery. Ann Thorac Surg 17157, Macmanus Q, Okies JE, Phillips SJ, Starr A: Surgical con-

5 188 The Annals of Thoracic Surgery Vol 41 No 2 February 1986 siderations in patients undergoing repeat median sternotomy. J Thorac Cardiovasc Surg 69338, Dobell ARC, Jain AK Catastrophic hemorrhage during redo sternotomy. Ann Thorac Surg 37273, Idriss FS, Markowitz A, Nikaidoh H, et al: Insertion of Hancock valve for pulmonary valve insufficiency in previously repaired tetralogy of Fallot. Circulation 54:Suppl2:100, Lappen RS, Muster AJ, Idriss FS, et al: Masked subaortic stenosis in ostium primum atrial septa1 defect: recognition and treatment. Am J Cardiol52:336, Loop FD: Catastrophic hemorrhage during sternal reentry (editorial). Ann Thorac Surg 37271, DeLeon SY, Idriss FS, Ilbawi MN, et al: Neointimal obstruction of Carpentier-Edwards valved conduit in two patients with modified Fontan procedure. Ann Thorac Surg 34:586, Cliff WJ, Grobety J, Ryan GB: Postoperative pericardial adhesions: the role of mild serosal injury and spilled blood. J Thorac Cardiovasc Surg 65:744, Asanza L, Rao G, Voleti C, et al: Should the pericardium be closed after an open-heart operation? Ann Thorac Surg 22532, Laks H, Hammond G, Geha AS: Use of silicone rubber as a pericardial substitute to facilitate reoperation in cardiac surgery. J Thorac Cardiovasc Surg 82:88, Meus PJ, Wernly JA, Campbell CD, et al: Long-term evaluation of pericardial substitutes. J Thorac Cardiovasc Surg REVIEW OF RECENT BOOKS International Trends in General Thoracic Surgery. Volume 1, Lung Cancer Edited by Norman C. Delarue, M.D., and Henry Eschapasse, M.D. Philadelphia, Saunders, pp, illustrated, $45.00 Reviewed by P. Kent Harman, M.D. This first volume of a new series devoted to specific areas of general (non-cardiac) thoracic surgery is an international dialogue on lung cancer. Seventy-five authorities from around the world, representing the fields of thoracic surgery, internal medicine, pulmonary medicine, oncology, physiology, radiology, pathology, and statistics, have contributed to this text. Twenty-seven chapters on five general areas discuss topics such as histogenesis, staging, surgical treatment, adjuvant therapies, chemotherapy, radiation therapy, immunotherapy, interferon therapy, occult lesions, recurrent disease, management of inoperable disease, follow-up of treated patients, and quality of life after treatment. Each specific topic is discussed indepth by an international authority and follows with a discussion by an equally authoritative source from a different country. The chapters are comprehensive and current; the discussions are critical and thought provoking. Recent research advances are discussed in context of their clinical applicability. Tables nicely summarize many important clinical series throughout the text. The current results of the large clinical study groups are presented as well as future plans for the study groups presently underway. Opinions are infrequently expressed in the absence of supporting data. There is a noticeable variation in style throughout the book, but continuity is remarkably well preserved, without redundancy. The international editorial board has successfully constructed a most attractive clinical reference on the topic of lung cancer, which is the leading cause of death from malignancy in the United States. As Dr. Carmack Holmes points out in the text, a small increase in the survival rate of lung cancer victims would affect a large number of patients. The information disseminated through this book represents a serious attempt at improving that survival rate. This book should gain appreciation from all surgeons, internists, and radiologists who treat patients with pulmonary malignancy and should be required reading for surgical house officers after the third year of training. San Antonio, TX