Conservative Management of Chylothorax after Coronary Artery Bypass Grafting

Abstract

Chylothorax is rare as a sequela to cardiac surgery. Its prevalence in cardiothoracic procedures is 0.3% to 1.5%; after median sternotomy, it is still more unusual.1,2 It is more frequent in pediatric than in adult cardiothoracic surgery. 3-5Postoperative chylothorax is associated with high rates of morbidity and mortality. 6 It can cause metabolic disturbances, nutritional deficiencies, respiratory disorders, immunodeficiency and infections, prolonged hospitalization, and high treatment costs. 7,8 Chylothorax after coronary artery bypass grafting (CABG) is rare, but it occurs most often if the left internal mammary artery (LIMA) has been used as a graft. We describe 2 cases of chylothorax that developed in adults after CABG, both of which were treated successfully with medical therapy alone. Case Reports Patient 1A 60-year-old man was admitted to our institution after a sudden onset of chest pain that radiated to his left arm. Coronary angiographic results led our heart team to perform CABG.After a median sternotomy, the LIMA was harvested as a peduncle, the pleura was incised, and the saphenous vein was harvested. First, the reversed saphenous vein graft was anastomosed to the 2nd diagonal branch (D2). Then the LIMA was anastomosed to the left anterior descending coronary artery (LAD). After the proximal anastomosis, the patient was weaned from cardiopulmonary bypass.The operative and first postoperative days were eventless. On the 2nd postoperative day, pale pink discoloration of the pleural drainage fluid was noticed. Chylothorax was diagnosed when biochemical analysis of the pleural fluid revealed total cholesterol, 43 mg/dL; triglycerides, 398 mg/dL; glucose, 67 mg/dL; and total protein, 2.7 g/dL. Pleural drainage was 100 to 250 mL/d.From the outset, the patient was given nothing by mouth but received, via total parenteral nutrition (TPN), a low-fat diet rich in medium-chain fatty acids (MCFA) (total calorie intake, 1,800 kcal/d. In addition, intravenous somatostatin was started (infusion rate of 3.5 µg/kg/hr for the first 48 hr, increased to 5 µg/kg/hr for the next 48 hr, and then to 7 µg/kg/hr for the 3rd 48 hr). No side effects-such as hypersensitivity, hypotension, or hypoglycemia-were noted.On the 7th postoperative day, the patient's oral intake of a low-fat diet was started. The pleural drainage fluid decreased during the course of this conservative therapy. The chest tube was removed on postoperative day 13, after the drainage of fluid had ceased. Follow-up chest radiography yielded normal results. The patient was dis-

Chylothorax after coronary artery bypass surgery. Report of a case and review of the literature

“…If it doesn't respond to conservative management, invasive management must be adopted. This complication can lead to deleterious consequences like immunosuppression, dehydration, malnutrition and respiratory dysfunction in a patient who is already recovering form a major open-heart surgery [6]. But luckily, the incidence is rare [1].…”

“…Most authors have used a dose of 50e100 mg subcutaneously for 10e14 days. If somatostatin is used, it must be used intravenously because of its short half-life [6]. Side effects such as hypoglycemia and hypotension should be looked for when treating patients with octreotide.…”

Conservative Treatment of Chylothorax After Coronary Artery Bypass Grafting: Case Report

“…[1][2][3][4] Koroner baypas cerrahisi sonrası ise %009 gibi çok daha nadir bir oranda görülmektedir. 5 Anterior mediasten cerrahisinde (timus, aort anevrizması ya da koarktasyonu veya duktus arteriyozus cerrahisi) aberran lenfatikler, LIMA hazırlanmasında proksimal böl-gede lenfatik yollar yada duktus yaralanabilir.…”

“…2,3 Şilotoraks tedavisinde oktreotid dışında sklerozan bir madde olan OK-432 (Picibanil), antiinflamatuar ilaçlarla (biyotalk, antibiyotik) kimyasal plörodez yapılabilir ya da intravenöz (IV) etilefrin HCl'nin sempatomimetik etkisiyle ana lenfatik kanallardaki düz kas etkisiyle şiloz akıntı azaltılabilir. 1 Medikal tedaviye rağmen 1.000 mL/gün ve üzerinde drenaj olan riskli hastalarda plöroperitoneal şant, lenfatiklerin transabdominal perkütan embolizasyon ve blokajı başarılı sonuçlar verebilir. Perkütan kateter embolizasyonun başarısı %50'den azdır.…”

Surgical technique and chylothorax following coronary artery bypass grafting

“…According to our experience, we suggest that the surgeon should maximize the left internal mammary artery conduit's length at the proximal end of the pedicle. [ 2 ] Damage to lymphatic channels during LIMA harvesting by electrocautery as already stated by the authors is the main destructive mechanism. Another probable cause is the division of the thymus gland and damage to the thymic lymphatic channels by electrocautery, in cases like aortic or mitral valve replacement when LIMA is not involved.…”