Makindo Medical Notes.com

Related Subjects: |Respiratory Failure |Non invasive ventilation (NIV) |Intubation and Mechanical Ventilation

About

• Carbon dioxide embolism can occur during insufflation of the abdomen in laparoscopic surgery.
• This can cause haemodynamic instability as the embolism may cause obstructive shock by blocking the outflow of the right ventricle.

Aetiology

• Insertion of the insufflation needle into a solid organ or large vessel can lead to a carbon dioxide embolism.
• As the embolism travels through the venous system this can cause obstruction of the right side of the heart leading to haemodynamic compromise.
• There is a significant risk during bariatric surgery as organs such as the liver can be significantly enlarged.

Clinical

• A sudden drop in EtCO₂ during insufflation is commonly seen in a carbon dioxide embolism. Although it can also lead to an increase in EtCO₂.
• New murmurs during surgery can be caused by a carbon dioxide embolism. These are referred to as “mill-wheel" murmurs.
• Carbon dioxide can lead to haemodynamic collapse and cardiac arrest.
• If a large vessel has been cannulated by the insufflation needle, then there is a risk of haemorrhage during insufflation and after removal of the needle.

Investigations

• CA TOE is the best investigation to determine a carbon dioxide embolism.

Pathology

• Carbon dioxide is used to create pneumoperitoneum as it is inert, cheap (collected as a by-product of other manufacturing processes) and less combustible than air.
• As the carbon dioxide embolus travels to the right side of the heart it can cause obstruction, prevent blood flow into the pulmonary vasculature. It can also raise pulmonary pressure (pulmonary hypertension). There is a risk of right and left heart failure, hypotension leading to cardiac arrest and arrhythmia.
• Unlike an air embolism, there is typically less effect on pulmonary function is seen with a carbon dioxide embolism, for example bronchospasm.
• There is a risk of a paradoxical embolus if the patient has a patent foramen ovale.

Management

• Early recognition is key, as insufflation should be immediately stopped, and the abdomen should be deflated.
• The patient should be oxygenated with 100% oxygen.
• Ensure that you are not delivering nitrous to the patient.
• Rapid volume resuscitation to increase central venous pressure may help to overcome the obstruction cause by the emboli.
• Vasopressors or inotropes may be required to maintain cardiac output.
• Place in left lateral decubitus and Trendelenburg. This may move the embolism to the apex of the right atrium, thereby removing the obstruction.
• If central venous access is in situ, then consider aspiration.
• Extracorporeal membrane oxygenation or hyperbaric oxygen could be considered.
• ALS algorithm if cardiac arrest.

References

• Park, Eun Young, Ja-Young Kwon, and Ki Jun Kim. "Carbon dioxide embolism during laparoscopic surgery." Yonsei medical journal 53.3 (2012): 459-466.