[1] DANDERYD HOSP,KAROLINSKA INST,DEPT ANAESTHESIA & INTENS CARE,STOCKHOLM,SWEDEN
[2] DANDERYD HOSP,KAROLINSKA INST,DIV PEDIAT,STOCKHOLM,SWEDEN
[3] KAROLINSKA INST,DEPT PHYSIOL,S-10401 STOCKHOLM,SWEDEN
[4] KAROLINSKA INST,INST ENVIRONM MED,S-10401 STOCKHOLM,SWEDEN