| Vital Sign | Definition |
|---|---|
| Blood pressure | The pressure or tension of the blood within the systemic arteries, maintained by the contraction of the left ventricle, the resistance of the arterioles and capillaries, the elasticity of the arterial walls, as well as the viscosity and volume of the blood (Stedman, 1995). |
| Heart rate | A measure of the heart's beat, recorded as the number of beats per minute (Stedman, 1995). |
| Temperature | The degree of temperature, an indicator of the presence of disease, or health threat independent of other signs gathered from simple physical diagnosis. |
| Respiratory rate | Frequency of breathing, recorded as the number of breaths per minute (Stedman, 1995). |
| Oxygen saturation | Oxyhemoglobin saturation according to the absorption of light. It can provide early warning of pulmonary or cardiovascular deterioration (Tintinalli, Kelen & Stapczynski, 2000). |
| Pain | A noxious sensation transmitted by specialized nervous structures to the brain, where its perception is modified by cognition and emotion (Paris, 1989; Tintinalli, et al., 2000). |