ASD and VSD Flow Dynamics and Anesthetic Management

Abstract

Atrial septal defects and ventricular septal defects are often encountered in patients presenting for treatment under anesthesia. The flow mechanisms for both defects are predominantly left to right shunting prior to long-term maladaptive changes that may occur. Close examination of the shunt dynamics demonstrates a minor right to left shunt that occurs as well. The article discusses these dynamics and the impact on an anesthetic plan.

Anaesthetic management of an infant posted for ventricular septal defect closure with right-sided eventration of diaphragm

“…At times, the PH may exceed aortic outflow pressure leading to a right –to-left shunt with consequent desaturation, hypoxia and cyanosis. [ 7 ] In the present scenario, there was a possibility of worsening of PH and shunt reversal in the presence of already existent pulmonary hypoplasia and systemic hypotension due to mediastinal shift which eventually could lead to hypoxaemia. Hence, measures were taken to prevent high flows and high inflation pressures which would aggravate this precarious situation.…”

“…At the same time, anaesthetic goals of managing VSD such as optimisation of preload, avoidance of hypovolaemia, maintaining normal SVR and preventing acute increases in PVR due to hypoxia, hypercarbia, acidosis and sympathetic stimulation were adhered to. [ 7 ] As there was a probability of right ventricular dysfunction in the presence of severe PH, inotropic supports such as adrenaline and milrinone were used during weaning from cardiopulmonary bypass. In diaphragmatic eventration, use of inhalation agents is controversial as it may inhibit hypoxic pulmonary vasoconstriction and worsen V/Q mismatch so, isoflurane was used, as it inhibits HPV least.…”

Left superior pulmonary vein connected to superior vena cava vein in a patient with situs inversus totalis: A challenging diagnosis

“…In the present case, early LA contrast was observed during transthoracic but not during transesophageal echocardiography, performed minutes apart. This discordance likely results from acute changes in the pressure gradient across the defect, to which stress and/or conscious sedation may have contributed, similarly to what may occur in “classical” atrial septal defects . It is common practice to restrain bubble studies to transesophageal echocardiography; our case demonstrates that injecting bubbles also during the transthoracic examination might provide additional diagnostic clues.…”

Pulmonary Congestion Due to Right and Left Heart Output Mismatching: A Case Report and Literature Review

“…In some congenital heart disease patients, such as atrial septal defect (ASD) or ventricular septal defect (VSD) patients, there will be a mismatching between the right and left heart cardiac output (Yen, 2015). However, there will be a balance between the right heart inflow and outflow tract.…”