Generally, waking from a coma depends on why the person is in a coma. Strictly defined a coma could be considered any GCS score of 8 or less.
Pharmacologically induced comas (with pentobarbital) are used by most trauma neurosurgeons as a late option for medical treatment of elevated intracranial pressure trying to prevent secondary injury. Earlier treatments include raising head of bed, sedation, paralytics, hyperventilation, ventriculostomy (drain CSF), and Mannitol or hypertonic saline (osmotic agents). If these options fail, then at least at my hospital, we would consider a barbituate coma. So, if your friend got to the point where he is in a barb coma, MOST likely he was already in coma from the traumatic brain injury itself (primary injury, rotational/angular injury with Diffuse Axonal Injury likely) and is having a lot of cerebral edema with elevated intracranial pressure that was likely being treated with other earlier options as above, but these options likely were not completely successful. The barb coma will likely be a deeper coma (hopefully) than the coma that was secondary to the trauma itself. Barb coma helps lower intracranial pressure (ICP) and reduces the metabolic demands of the brain, decreasing the brain's oxygen requirements. It can take several days to have the effects of the barbs wear off after the barb drop has been stopped. Most patients are monitored with continuous EEG's to prove the patient is in burst-supression.
Now, assuming the patient did not herniate, stroke a large segment of their brain, have a large intracerebral hemorrhage, and did not have severe diffuse axonal injury involving the brainstem or midbrain, and he doesn't have diffuse bilateral cerebral injury... then he has a chance of recovering from the coma that the trauma itself is causing. Also assuming there isn't any secondary injury from the elevated intracranial pressure.
2 weeks is not usually enough time to see if a person is going to "wake" up from a coma, although it sometimes happens this fast. It also depends on what level of coma they are in. If they are withdrawing or better (Motor score of 4 or 5) then they have a MUCH better chance of recovering to consciousness than if they are posturing (motor score of 2 or 3). In fact it is very rare from someone to regain consciousness with decerebrate posturing.
I have seen many people regain consciousness with a motor score of 4 or higher, but not all do. Sometimes it takes MONTHS even up to a year or two. Generally, you will have the maximal recovering from the traumatic injury within 2 years. After 2 years it is highly unlikely to make any siginificant improvements in neurological function. Of those that do wake up, many are never the same, and are never able to live "normal" lives... but some do. Even the higher functioning of them typically have cognitive deficits including concentration difficulties, memory problems, and higher order executive functioning.
Regarding the doctors looking for pictures for reconstructing his face, they are likely not neurosurgeons and may or may not be aware of the severity of his brain injury and the likelihood of him regaining consciousness.
As others have stated, you should talk directly with the neurosurgeons responsible for his care to get the most accurate prognosis of your friend, but many times even the neurosurgeon taking care of the patient can't know for sure.
This was mostly a little medical candy for the med students on this site.
