Dr. Chase is trying to intubate a patient when having a glove on his right hand alone. Seconds earlier he had gloves on both his hands, as well as just seconds after.
The tick House pulls out at the end has six legs (which is excellently visible in a close-up on his gloved hand) - this would indicate it is an insect. But ticks are arachnids, not insects; and, as all other arachnids (such as spiders or scorpions), they have eight legs, while the insects have six.
The intubation scene in "Safe" is unique in the series: it commits the least amount of errors in the procedure. The head of the patient's bed is lowered (done every time), all the pillows are removed from beneath her head (usually one is left beneath, which is incorrect), Foreman hyperextends the patient's neck (usually this is never seen in the series), and then Chase inserts the laryngoscope and intubates the patient.
When Melinda's heart rate began decreasing towards the conclusion, administration of atropine would do nothing because the heart becomes denervated post-transplant.
The auto injection pen used in the first scene is to be injected into a major muscle group like the upper thigh. injecting into the shin of the lower leg would be ineffective.
Tics do not inject venom.
After House finds the tick and he and Wilson are walking down the hall House falls down. It is discovered that Houses cane has broken and Wilson informs him that somebody must have filed his cane in half while he (House) was sleeping. If that was the case then moments earlier when House used his cane to keep Foreman from accessing the elevator buttons then the cane would have broken during that struggle.
Dr. Foreman explains to the patient's parents that when blood is spun in a centrifuge, the white blood cells, being heaviest, migrate to the bottom of the tube, followed by red cells, platelets, and plasma, in that order. In fact, the red cells are heaviest and fill the bottom of the tube, followed by white cells and platelets (more or less together), and plasma.