Malpractice insurance protects hospitals and emergency room medical providers. The insurance companies have a regiment of lawyers whose job it is to aggressively fight medical malpractice cases. They are usually not particularly anxious to hurry the case along.
Generally, the longer the delay, the more likely that key witnesses become unavailable. Or they may hope that the plaintiff will become disheartened and accept a settlement offer. Medical malpractice cases are very difficult. As a general rule, medical malpractice suits progress slowly, often taking months or even years to conclude.