Upvote:8
The probable medical reason is pleural efflusion, caused by hypovolemic shock and congestive heart failure.
Hypovolemic shock, also called hemorrhagic shock, is a life-threatening condition that results when you lose more than 20 percent (one-fifth) of your bodyβs blood or fluid supply.
This would likely have been a result of the flogging prior to the crucifixion.
From gotquestions.org:
Those who were flogged would often go into hypovolemic shock, a term that refers to low blood volume. In other words, the person would have lost so much blood he would go into shock.
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Prior to death, the sustained rapid heartbeat caused by hypovolemic shock also causes fluid to gather in the sack around the heart and around the lungs. This gathering of fluid in the membrane around the heart is called pericardial effusion, and the fluid gathering around the lungs is called pleural effusion. This explains why, after Jesus died and a Roman soldier thrust a spear through Jesusβ side (probably His right side, piercing both the lungs and the heart), blood and water came from His side just as John recorded in his Gospel (John 19:34).