*4.1.6 Number of intubation attempts*

The NAP4 registry has found the number of attempts, and trials are significantly associated with higher rate of aspiration 22% regurgitation, 13% aspiration were reported after the second attempts [1].

## *4.1.7 Underlying pathologies*

#### *4.1.7.1 Diabetes mellitus*

Diabetes is a common metabolic and endocrine disease, complicated with diabetic gastroparesis, known as gastric paralysis. It was found that hemoglobin A1c value of more than 7%, could lead to delayed gastric emptying, by decreasing the frequency of gastric contraction, while the risk score of aspiration increase significantly [16].

#### *4.1.7.2 Advanced age*

Old age is an independent risk factor for delayed gastric emptying, as it is common in elderly patient to have anorexia, dyspepsia and impaired gastric peristalsis [17].
