It is possible to inflate an air mattress using a vacuum that includes a hose attachment. Before beginning, be sure to empty the vacuum of dust and debris, and run the vacuum outside for a few minutes to make sure it is entirely empty.
To begin, lay the air mattress out on the floor and spread it flat. Open the valve and place the nozzle of the vacuum hose over or into the valve on the mattress, adjusting for the tightest fit. If the fit remains loose, adapters are available from camping or sporting goods stores. Use the reverse or exhaust mode on the vacuum to fill the mattress with air. Once the mattress is inflated, remove the vacuum and quickly close the mattress valve.