Persistent left superior vena cava in right hemiarch replacement under deep hypothermic circulatory arrest:A case report

BACKGROUND Persistent left superior vena cava(PLSVC),a relatively rare thoracic vascular malformation,can inconvenience perfusionists and operators when encountered during deep hypothermic circulatory arrest(DHCA).CASE SUMMARY Herein,we describe the case of a patient with concurrent giant aortic arch aneurysm,aortic stenosis,and PLSVC.To treat these conditions,we performed right hemiarch and aortic valve replacements under DHCA.Notably,we applied“bilateral superior vena cava retrograde cerebral perfusion(RCP)”for cerebral protection,which significantly optimized the surgical procedure and reduced the risk of postoperative complications.The patient was discharged 14 d after surgery with no complications.CONCLUSION Surgical intervention for PLSVC under DHCA can be performed using the bilateral superior vena cava RCP approach.

A novel rat model of cardiopulmonary bypass for deep hypothermic circulatory arrest without blood priming

Background Large animal cardiopulmonary bypass （CPB） models are expensive,and prevent assessment of neurocognitive function,and difficulties with long-term recovery.The purpose of this study was to establish a novel rat model of cardiopulmonary bypass for deep hypothermic circulatory arrest without blood priming.Methods Twenty adult male Sprague-Dawley rats weighing 450-560 g were randomized to CPB with deep hypothermic circulatory arrest （DHCA） and control groups,with 10 rats each.The experimental protocols,including blood and crystalloid fluid administration,anesthesia,orotracheal intubation,ventilation,cannulation,and heparinization were identical in both groups.After inducing cardiac arrest,the circuit was turned off and rats were left in a DHCA state for 15 minutes.Rats were rewarmed to 34℃ to 35℃ over a period of 36 to 42 minutes using CPB-assisted rewarming,a heating blanket,and a heating lamp along with administration of 0.1 mEq of sodium bicarbonate and 0.14 mEq of calcium chloride.The remaining priming volume was reinfused and animals were weaned from CPB.Results All CPB with DHCA processes were successfully achieved.Blood gas analysis and hemodynamic parameters were in the normal range.The vital signs of all rats were stable.Conclusions Our CPB circuit has several novel features,including a small priming volume,active cooling/rewarming processes,vacuum-assisted venous drainage,peripheral cannulation without thoracotomy or stemotomy,and an accurate means of monitoring peripheral tissue oxygenation.

Perioperative factors analysis in patients with aortic aneurysm and aortic dissection aneurysm

This study was undertaken to analyze the perioperative factors and complications that influence the final outcome after deep hypothermic circulatory arrest and superficial hypothermia during operations on aortic aneurysms from Jan 2000 to Jun 2004. The results show that deep hypthermic circulatory arrest group provided a high risk of pulmonary insufficiency-hypoxemia and temporary neurological dysfunction in complication but not increased the risk of hospital mortality.

A Cardiac Surgical Perspective on Hypothermia for Protection of Neural Tissues

Background: In clinical and basic science medicine, we often isolate ourselves in silos, unaware of developments in other related disciplines. Our team has had substantial experience, both in the operating room and in the laboratory, with protecting the brain and the spinal cord via hypothermia. Herein, we briefly share this experience with our colleagues in Neurology, eager for comments and advice from the neurologic perspective. Methods: 1) Clinical brain protection via deep hypothermic circulatory arrest (DHCA) for surgery of the aortic arch. For aortic arch replacement (performed for aortic arch aneurysm or aortic dissection), the aortic arch must be opened and native perfusion stopped. We have decades of experience in many hundreds of patients with this technique. This experience is reviewed. 2) Experimental protection of the spinal cord via cooling. We review our laboratory experience with a novel, recirculating cooling catheter for the vulnerable spinal cord. 3) Experimental protection of the brain via an intraventricular cooling catheter. We review our laboratory experience cooling the brain with a balloon-tipped catheter residing the lateral ventricles. Results: 1) Deep hypothermic circulatory arrest for aortic arch surgery provides superb brain protection for periods up to 45 minutes or longer. Clinical neurologic function, and quantitative neurologic tests, show excellent brain preservation. 2) The novel spinal cooling catheter provides excellent cooling of the spinal cord in a large animal model, without apparent injury of any type. 3) The intraventricular brain cooling catheter provides excellent cooling of the brain, documented by both direct temperature probe and high-tech brain imaging. Conclusions: We wish herein (in this article) to share this experience across our disciplines (Cardiac Surgery and Neurology). We welcome advice from the Neurology community on these surgically-directed methods for cooling and protection of neurological tissue in both the brain and the spinal cord.