Risk factors:
(1) elevated pressures of carbon dioxide gas
(2) large denuded surface exposed
(3) perforation of a large vein
Findings depend on the size of the embolus:
(1) abrupt changes in end tidal carbon dioxide tension (ET CO2), with an initial increase followed by a decrease
(2) oxygen desaturation on pulse oximetry
(3) unchanged airway pressure
(4) possibly a cardiac murmur (hydroaeric "millwheel" type)
(5) obstructed blood flow with right sided heart failure, increased pulmonary artery pressure and acute pulmonary edema. Patients may exhibit tachypnea, gasping and diffuse pulmonary wheezing.
(6) decreased cardiac output with hypotension and cyanosis
(7) ECG changes including tachyarrhythmias, ventricular fibrillation and cardiac arrest
(8) rare complications include passage of gas through a patent foramen ovale to cause arterial occlusion
Confirmation: transesophageal echocardiography
Management:
(1) Discontinue insufflation and deflate accumulated gas.
(2) Place the patient in the left lateral decubitus position (Durant's position) to relieve any mechanical obstruction in the right ventricular outflow tract.
(3) Placement of a central venous catheter can sometimes release the gas bubble.
(4) Cardiopulmonary bypass may be needed in some patients to release the gas.
