What Could Cause Numbness?

On a recent motorcycle trip I suffered all over numbness especially in my face, hands and legs. I couldn't open my mouth very far and my lips were tightly puckered. I also lost all function in both hands and my leg muscles were having spasms. My o2 sat was 88 until I was on oxygen for an hour or so. No high blood sugar. No abnormalities on ekg ( I do have a history of tachycardia). Bp was a 148/99. Electrolytes were normal. I'm 34 and otherwise healthy.. any insight on the cause ?