A few years ago I spoke with the German physician who conducted the low dose trials along with the deep coma treatment. Based on his findings at that time he had decided to stop the low dose trials, he found that there was limited benefit to the patients and it required ongoing booster treatments. He advised me against it, instead he recommended lidocaine infusions before trying the deep coma option. I have a copy of his published findings some where in my files which I can send to you if you pm me with your email. I know further research has been done in the USA and elsewhere but I am not aware of any published findings. Lidocaine definitely has far less side effects than ketamine and is quite effective.

MsL