Unexplained intraoperative cardiac tamponade during thoracoscopic lobectomy: a case report.

Background: Cardiac tamponade is a life-threatening emergency characterized by reduced cardiac output and circulatory failure. It most commonly occurs during cardiac surgery, interventional cardiology procedures, pericardiocentesis, or central venous catheterization, as well as in the setting of acute myocardial infarction or aortic dissection. To the best of our knowledge, cardiac tamponade during video-assisted thoracoscopic surgery (VATS) lobectomy has not been reported and may has an insidious presentation, making diagnosis challenging in the absence of obvious pericardial injury. Case presentation: We report a case of unexplained intraoperative cardiac tamponade in a 74-year-old man undergoing VATS left upper lobectomy. During hilar vessel dissection, the blood pressure decreased to 82/65mmHg. The heart rate increased to 95 beats/min, requiring norepinephrine infusion (0.2-0.3 μg·kg⁻¹·min⁻¹) to maintain blood pressure. However, no bleeding was evident in the surgical field, hemoglobin and lactate levels remained stable, and oxygenation and airway pressures were unchanged. After considering and excluding major differential diagnoses, including tension pneumothorax, hypovolemic shock, and pulmonary embolism, intraoperative point-of-care transthoracic echocardiography (TTE) was performed and revealed pericardial effusion with echocardiographic features of cardiac tamponade. Creation of a pericardial window with drainage of approximately 200 mL of bloody fluid. Immediately, blood pressure rose to 170/90 mmHg and heart rate decreased to 82 beats per minute. No definitive source of bleeding was identified during the operation. On postoperative day1, the patient developed paroxysmal atrial fibrillation, which resolved after treatment with amiodarone. Serial TTE on postoperative days 1, 2, and 6 showed no significant abnormalities. The chest tube was removed on postoperative day 6, and the patient was discharged the following day. Conclusion: During VATS lobectomy, intraoperative hypotension that cannot be explained by blood loss or changes in ventilation parameters, particularly when accompanied by a narrowed pulse pressure, should prompt consideration of occult cardiac tamponade. Early point-of-care ultrasonography and timely pericardial drainage are essential for rapid diagnosis and hemodynamic stabilization.