| HOP | high oxygen pressure |
|---|---|
| HOT | health-oriented telecommunication; human old tuberculin; hyperbaric oxygen therapy; Hypertension Opt... |
| HPO | high-presure oxygen; hydroperoxide; hydrophilic ointment; hypertrophic pulmonary osteoarthropathy |
| HPPO | high partial pressure of oxygen; hydroxyphenyl pyruvate oxidase |
| IPPO | intermittent positive-pressure inflation with oxygen |