Question

A lady presented to the emergency department with a stab injury to the left side of the abdomen. She was haemodynamically stable and a contrast-enhanced CT scan revealed a laceration in the spleen. Laparoscopy was planned, but the patient's pO2 suddenly dropped as soon as the pneumoperitoneum was created. What is the most likely cause?

• A. Gas embolism through splenic vessels
• B. Injury to the left lobe of the diaphragm
• C. Inferior vena cava compression
• D. Injury to the colon

Hint:

Open vein plus pressurised CO2 the moment you insufflate equals gas in the circulation.

Answer 1

The Correct Option is A

Focus on timing and anatomy. The oxygen level crashed the instant gas was pushed into the belly, and the patient already had a torn spleen, an organ packed with thin-walled veins. When you insufflate the abdomen for laparoscopy, you pressurise it with carbon dioxide. If a large vein is lying open, that pressurised gas can be driven straight into the venous blood. The gas bubbles flow back to the right side of the heart and lodge in the pulmonary arteries, where they form an air lock that stops blood from picking up oxygen, so the $pO_2$ falls at once. Compare the alternatives. A diaphragm tear hurts breathing but does not give a knife-edge desaturation locked to insufflation. Squeezing the inferior vena cava drops the blood pressure rather than the oxygen. A colon injury causes contamination, not sudden hypoxia. The clean link between making the pneumoperitoneum and the immediate oxygen drop, in a patient with open splenic veins, is a carbon dioxide gas embolism.\[\boxed{\text{Gas embolism through splenic vessels}}\]