Plot hole: When Wilson does an ultrasound to check for cancer in Alex' ovaries he fails to notice the fact that she doesn't have a uterus. If he mistook her bladder for her uterus, which sometimes happens, she would have appeared to be missing her bladder instead. Yet Wilson doesn't pick up on anything being missing.
Plot hole: In the scene with Mikey in the NICU, the alarms start to go off, stating that he is in distress. The nurse screams "He's in V-fib!" and everyone rushes around him. In the next shot they show the heart monitor just before Chase shocks Mikey's heart. The problem is that the heart rate is so fast with one wide complex that it would actually be Supraventricular Tachycardia with 1 Premature Ventricular Contraction (SVT with 1 PVC), which is far less serious than V-fib and wouldn't require the heart to be shocked.
Plot hole: Since the doctors do not know the identity of the patient, Cole and Thirteen are given the car keys they found on the man and instructed to go to the area where he was found and try it in every car door. When House calls them, Thirteen says, "His car was towed and the tow gate's locked." House tells them to break in to the car impound. Given the only way for them to identify the car was using the keys, if the car's been towed away then it wasn't there for them to try the key in the first place.littlestar
Plot hole: The doctors tell House that blood tests did not show anything wrong with the teenage boy, but near the end of the episode, he realises that it is naphthalene poisoning. Naphthalene poisoning is something that is easily noticed by doctors through blood tests.