Landon was diagnosed with hypernatremic dehydration (a high concentration of sodium in the blood), cardiac arrest from hypovolemic shock (a condition where the liquid portion of the blood is dangerously low), and hypoxic - ischemic encephalopathy (a brain injury caused by oxygen deprivation). (romper.com)
Death can still ensue because of hypovolemic shock if not severe electrolyte abnormalities and acid - base imbalances. (mypetneedsthat.com)
There is a medical condition called hypovolemic shock. (faith.org.uk)