Comparison of the effectiveness and safety of a new de-airing technique with a standardized carbon dioxide insufflation technique in open left heart surgery: A randomized clinical trial

Totally endoscopic atrial septal defect repair using transthoracic aortic cannulation in a 10.5-kg-boy

INTRODUCTION

Although totally endoscopic surgery (TES) has been widely applied for the treatment of atrial septal defect (ASD), small children receive few benefits from this technique due to risks of the femoral cannulation.

CASE PRESENTATION

A 23-month-old boy, weighing 10.5 kg, with the diagnosis of sinus venosus ASD underwent successful repair by TES. We performed this surgery through 4 small trocars (one 12 mm trocar and three 5 mm trocars), without robotic assistance. In this case, we inserted the arterial cannula directly into the ascending aorta instead of the femoral artery (FA). The defects were repaired on the beating heart with CO₂ insufflation.

DISCUSSION

Femoral cannulation in small children pose some risks, such as increased arterial line pressure, critical lower limb ischaemia, and post-operative iliac or femoral arterial stenosis. Putting the arterial cannula directly into the ascending aorta is a good solution but is difficult to be performed through TES, especially in small children. The major concern of operating on the beating heart is the air embolism, which requires special preventative methods.

CONCLUSION

Transthoracic aortic cannulation may facilitate TES in small children. However, the safety and efficacy of this approach needs to be validated by larger studies preferably randomised controlled trials.

Atheroembolization and potential air embolization during aortic declamping in open repair of a pararenal aortic aneurysm: A case report

•

A case of microembolization in open repair of a pararenal aneurysm is presented.

•

Only a few out of hundreds of small arteries contained cholesterol emboli.

•

There was a possibility of remaining air in the aorta/graft at aortic de-clamping.

•

Air could have been whipped into pulsating blood causing air microembolization.

•

Air microembolization in open repair of pararenal aneurysms needs to be studied.

Introduction

When ischemic events ascribable to microembolization occur during open repair of proximal abdominal aortic aneurysms, a likely origin of atheroembolism is not always found.

Presentation of case

A 78-year old man with enlargement of the entire aorta underwent open repair for a pararenal abdominal aortic aneurysm using supraceliac aortic clamping for 20 min. Then the graft was clamped, the supraceliac clamp was removed, and the distal and right renal anastomoses were also completed. The patient was stable throughout the operation with only transient drop in blood pressure on reperfusion. Postoperatively the patient developed ischemia, attributable to microembolization, in legs, small intestine, gall bladder and kidneys. He underwent fasciotomy, small bowel and gall bladder resections. Intestinal absorptive function did not recover adequately and he died after 4 months. Microscopic examination of hundreds of intestinal, juxtaintestinal mesenteric, and gall bladder arteries showed a few ones containing cholesterol emboli.

Discussion

It is unsure whether a few occluded small arteries out of several hundred could have caused the ischemic injury alone. There had been only moderate backbleeding from aortic branches above the proximal anastomosis while it was sutured. Inadvertently, remaining air in the graft, aorta, and aortic branches may have been whipped into the pulsating blood, resulting in air microbubbles, when the aortic clamp was removed.

Conclusion

Although both atheromatous particles and air microbubbles are well-known causes of iatrogenic microembolization, the importance of air microembolization in open repair of pararenal aortic aneurysms is not known and need to be studied.

Pulmonary collapse alone provides effective de-airing in cardiac surgery: a prospective randomized study

OBJECTIVES

We previously described and showed that the method for cardiac de-airing involving: (1) bilateral, induced pulmonary collapse by opening both pleurae and disconnecting the ventilator before cardioplegic arrest and (2) gradual pulmonary perfusion and ventilation after cardioplegic arrest is superior to conventional de-airing methods, including carbon dioxide insufflation of the open mediastinum. This study investigated whether one or both components of this method are responsible for the effective de-airing of the heart.

METHODS

Twenty patients scheduled for open, left heart surgery were randomized to two de-airing techniques: (1) open pleurae, collapsed lungs and conventional pulmonary perfusion and ventilation; and (2) intact pleurae, expanded lungs and gradual pulmonary perfusion and ventilation.

RESULTS

The number of cerebral microemboli measured by transcranial Doppler sonography was lower in patients with open pleurae 9 (6-36) vs 65 (36-210), p = 0.004. Residual intra-cardiac air grade I or higher as monitored by transesophageal echocardiography 4-6 minutes after weaning from cardiopulmonary bypass was seen in few patients with open pleurae 0 (0%) vs 7 (70%), p = 0.002.

CONCLUSIONS

Bilateral, induced pulmonary collapse alone is the key factor for quick and effective de-airing of the heart. Gradual pulmonary perfusion and ventilation, on the other hand, appears to be less important.

Anesthetic Management for Cardiopulmonary Bypass

Cardiopulmonary bypass has revolutionized the practice of cardiac surgery and allows safe conduct of increasingly complex cardiac surgery. A brief review of the bypass circuit is undertaken in this review. A more thorough review of the anesthetic management is accomplished including choice of anesthetic medications and their effects. The inflammatory response to cardiopulmonary bypass is reviewed along with interventions that may help ameliorate the inflammation.

Simple Technique to Verify CO2 Diffusion with the CarbonAid� Device

It has become common practice in cardiac surgery to flood the operative field with CO₂ to facilitate deairing of the heart. However, CO₂ delivery is variable and verification of CO₂ delivery can be challenging. We report a simple, reliable method to confirm CO₂ delivery. This technique ensures that the benefits of CO₂ delivery are provided to the patient during the operation.

Comparison between transcranial Doppler and Coulter counter for detection of lipid micro embolization from mediastinal shed blood reinfusion during cardiac surgery

INTRODUCTION

Lipid micro embolization (LME) from re-transfused shed blood has been postulated to be a potential reason for short- and long-term cognitive dysfunction after cardiac surgery. The purpose of this investigation was to evaluate if transcranial Doppler (TCD) has the capacity to detect LME.

METHODS

Thirteen patients undergoing cardiopulmonary bypass surgery were investigated. Each patient's cerebral circulation was monitored with transcranial Doppler during the first two minutes after re-transfusion of shed blood and blood was simultaneously sampled and characterised by a Coulter counter.

RESULTS

Strong correlation was found between embolic loads, as measured by transcranial Doppler and Coulter counter (r=0.79, P<0.005).

CONCLUSIONS

This pilot study shows that non-invasive monitoring by transcranial Doppler could be a potential tool to monitor LME during cardiopulmonary bypass surgery.