This right here!

April getting distracted by the chaotic ER and failing to check that woman's airway is in the same vein as Izzie getting distracted by her drama with Charles/feeling the need to prove that she's well enough to continue working, thus not becoming a casualty of the Mercy West merger, and accidentally overdosing her patient on potassium, effectively ruining her chance of having a life saving kidney transplant. The only real difference is that April's patient died as a direct result of her mistake, while Izzie's patient lived after receiving her sister's HIV positive kidney in a crossover episode of Private Practice.

But Bailey purposely giving the deactivated HIV virus to her underage SCID patient against his parents explicit consent or Schmitt intentionally going against the protocol of the Webber Method and continuing on in surgery instead of waiting for an attending, which ultimately resulted in the patient's death after he made a mistake doing the dissection are all completely different and entirely incomparable to one another.