I Gave 16 Units Inj.human Mixtard To A Patient At

I gave 16 Units inj.human mixtard to a patient at 9pm.He was unconscious at 4am with GRBS of 36.He was maintaining a heart rate of 120,SpO2 95%without oxygen and pupils were reacting to light.dextrose 25% 200 ml was administered,blood sugar raised to 258.He was intubated due to his poor GCS.He exhibits decorticate posturing to painful stimulus.This happened 2 days ago,but still he is in coma,hemodynamically stable.He is a patient with Ca pancreas with spine mets and undergone whipples at 2013.Is this condition reversible?Is there any hope that he can regain his conciousness back?