“All That” alum Christy Knowings’ cause of death has been revealed to be cardiac arrest. Knowings died Aug. 11 at 46 years old. The former Nickelodeon star’s death certificate obtained by People Wednesday lists acute hypoxic respiratory failure and status asthmaticus as conditions leading to her death, with asthma being the underlying cause. Acute hypoxic respiratory failure is a life-threatening condition in which there’s not enough oxygen or too much carbon dioxide in your body, while status asthmaticus is an extreme asthma attack that doesn’t get better with standard treatments, according to the Cleveland Clinic. One of Knowings’ family…









