Rostik Zajtchuk

Initial and Long-term Results in the Management of Primary Chest Wall Neoplasms

One hundred ten patients with primary chest wall neoplasms were analyzed for long-term results. The diagnosis of 59 malignant and 51 benign tumors was confirmed by the Armed Forces Institute of Pathology. No deaths were associated with primary definitive therapy. Among the five most frequently encountered malignant tumor types, five-year survivals were obtained in 9 of 17 (53%) patients with fibrosarcoma, 8 of 9 (89%) patients with chondrosarcoma, 2 of 8 (25%) patients with solitary chest wall plasmacytoma (multiple myeloma), 1 of 6 (17%) patients with Ewings sarcoma, and 2 of 4 (50%) of patients with osteogenic sarcoma. Although the five-year survival appears to indicate therapeutic success in patients with Ewings sarcoma and osteogenic sarcoma, patients with chondrosarcoma or fibrosarcoma may have a more protracted course, and those with solitary plasmacytoma usually develop multiple myeloma. The findings suggest that radical surgical excision is the treatment of choice for chondrosarcoma; radical surgical excision combined with chemotherapy, for fibrosarcoma and osteogenic sarcoma; surgical excision combined with radiation and chemotherapy, for Ewings sarcoma; and systemic surveillance and therapy, for pathologically confirmed solitary plasmacytoma.

Prevention of Ventricular Fibrillation After Myocardial Revascularization

Ventricular fibrillation during reperfusion after aortic cross-clamping for coronary artery bypass grafting may cause subendocardial injury. We investigated the use of lidocaine to prevent ventricular fibrillation during this period. In a blind, prospective, randomized trial, 91 consecutive patients undergoing elective coronary artery bypass graft procedures were given lidocaine (2 mg/kg) or normal saline immediately before removal of the aortic cross-clamp. The groups were similar with respect to demographic, clinical, and intraoperative variables. Myocardial preservation techniques were similar in both groups. Of 47 patients receiving lidocaine, 38 recovered a supraventricular rhythm without ventricular fibrillation, compared with only 5 of 44 patients in the control group (p less than .001). When ventricular fibrillation occurred, patients in the control group required a greater number of direct-current countershocks (2.31 versus 1.86) to convert to sinus rhythm. Transient heart block, requiring temporary pacing, developed in 3 patients in the lidocaine group, compared with 1 patient in the control group. There was no significant difference between the groups in the requirement for perioperative inotropic support (6 of 47 versus 6 of 44) or the number of myocardial infarctions (2 of 47 versus 1 of 44), and there were no deaths in either group. Lidocaine infusion immediately before removal of the aortic cross-clamp significantly reduces the incidence of ventricular fibrillation during the reperfusion period after cardiopulmonary bypass.

Evaluation of Serum Creatine Kinase and Lactate Dehydrogenase in Experimental Myocardial Infarction, Atriotomies, and Thoracotomies

Myocardial infarction causes elevation of the serum myocardial-associated isoenzyme of creatine kinase (CK-MB) and a serum isoenzyme of lactate dehydrogenase (LDH1). Since atrial myocardium has as much CK-MB as ventricular myocardium, surgical manipulation of the atrium could cause elevation of serum CK-MB in the postoperative period. The distribution of LDH isoenzymes is different between atrial and ventricular myocardium. Hence, surgical procedures on the atrium could, theoretically, cause different changes in serum LDH isoenzymes than those seen after acute myocardial infarction. This study was conducted to ascertain whether surgical manipulation of the atrium could cause changes in these two serum enzyme systems that might be confused with those seen after acute myocardial infarction. Right thoracotomies were performed on 20 dogs. Each dog then was assigned randomly to one of four groups: thoracotomy (control), placement of atrial pursestring sutures, atriotomy, or acute perioperative myocardial infarction. Serum total and isoenzyme distributions of CK and LDH were measured for 48 hours in all animals. The results suggest that significant elevations of serum CK-MB occurred even after small atriotomies. Confirmation of a ventricular myocardial origin of postoperative serum CK-MB bands was obtained by analysis of serum LDH isoenzymes in that the ratio of LDH1 to LDH2 and the absolute value of serum LDH1 became elevated only after acute perioperative myocardial infarction and not after atriotomy.

An Analysis of the Isoenzymes of Creatine Phosphokinase and Lactic Dehydrogenase in the Esophagus

Surgical manipulation of muscular organs can cause alterations of the serum isoenzymes of creatine phosphokinase (CPK) and lactic dehydrogenase (LDH), which are frequently used to confirm the diagnosis of myocardial infarction (MI). Since the content of these enzymes and their isoenzymes has not been established for the esophagus, an experiment was conducted to evaluate and compare the enzymes in postmortem specimens from humans and fresh canine specimens. One gram transmural esophageal sections were taken from specimens having no demonstrable disease. All samples were homogenized individually in Ringers lactate solution and centrifuged, and the supernatants were analysed for the respective isoenzyme distributions by agarose gel electrophoresis. From the study we drew the following conclusions: (1) all three isoenzymes of CPK (including CPK-MB, the myocardialisoenzyme) are present in the esophagus; (2) LDH, the isoenzyme of LDH most prevalent in myocardium, is the least common of the five isoenzymes of LDH in the esophagus; (3) the dog is an appropriate model for studying changes of these isoenzymes after operation; and (4) any potential confusion in diagnosing postoperative MI due to esophageal CPK-MB in the serum can be resolved, theoretically, by analyzing LDH serum isoenzymes. In myocardial infarction, LDH becomes the predominant isoenzyme, whereas esophageal injury should be associated, theoretically, with a serum LDH isoenzyme pattern in which LDH is the least prevalent isoenzyme.

Rib fracture healing in experimental flail chest.

Sixteen dogs were placed under general anesthesia and flail segments of the left chest were created by transecting ribs 7,8,9, and 10 anteriorly and posteriorly. Fractures were 10 cm apart so that a 10-cm flail segment encompassing four ribs was created. In Group I, the control (N = 5), the chest wall muscles were closed without any stabilization of the fractures. Group II (N = 5) had stabilization of both anterior and posterior fracture sites by polypropylene sutures. Group III (N = 6) had stabilization of the fractures in ribs 7 and 8 with 2.5-cm bone grafts taken from the left fourth rib. Ribs 9 and 10 were stabilized by polypropylene sutures. The study established a canine model for flail chest. It also showed that strut stabilization of rib fractures with bone grafts promotes better healing than suture stabilization. It suggests that using bone grafts taken from another rib to stabilize flail segments may be unsatisfactory since the rib used as a donor showed no signs of regeneration at 30 days.