Inclusion Criteria:  Subjects with Multiple myeloma Subjects must be 18 years old Karnosfsky Performance of greater than 70 percent Adequate hepatic, cardiac and pulmonary function Subjects should have New York Heart Association Functional Classification of: Class 1 or Class II.  Exclusion Criteria:  Pregnant or breastfeeding Severe chronic obstructive pulmonary disease requiring oxygen supplementation History of spontaneous pneumothorax Active ear/sinus infection Sinus surgery within the last 5 years Claustrophobia History of recurrent seizures within 5 years of study enrollment Evidence of pneumothorax or significant pulmonary fibrosis on chest imaging within 60 days of transplant Prior chest surgery involving thoracotomy or prior direct irradiation to the lungs Subjects who have had intrathecal chemotherapy within 2 weeks of starting preparative regimen or cranial irradiation within 4 weeks of starting preparative regimen Active and uncontrolled viral, fungal or bacterial infection Use of tobacco 72 hours prior to transplant