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12.1.1. Health indicators

Health indicators

The disease is the alteration of the normal functioning of the organism. The health indicators indicate its good condition.

Vital signs

The vital signs are the set of values ​​that inform us about the state of health of a person. The most important ones are:

Body temperature

The thermometer is the instrument used to measure the temperature, which is normally between 36.5 and 37.2 ºC. The temperature may vary depending on the ambient temperature, the time it is taken or if there is a disease.

Thermometers have traditionally been made of mercury, but they are toxic to human health and the environment, which is why they are no longer manufactured in Europe. Now, they are made of other materials and digital, easy to use, such as the infrared thermometer , which measures the temperature in the ear.

The body temperature can be measured in the mouth, armpit or rectum, although we should not compare values for different results. Depending on the result, these situations can occur:

  • Hypothermia: Below normal temperature (36.5 ºC) when exposed to low temperatures.
  • Low-grade fever: Between 37.1 and 37.9 ºC.
  • Fever: More than 38 ºC .

Interactive activity: Comparison between influenza and malaria.

The pulse

The pulse is produced by the expansion of the arteries when the heart contracts. It can be detected in parts of the body where the arteries are close to the skin, such as in the wrists and neck.

In a healthy adult, the pulse has a constant rate of 60 - 80 beats per minute, although it varies depending on age, if you have just done physical exercise or if you have a fever, for example. Depending on the frequency, these situations can occur:

  • Arrhythmia: The heart rhythm is irregular.
  • Tachycardia: The heart beats too fast without having done physical exercise.
  • Bradycardia: The heart beats too slow.

Respiratory rate

With pulmonary ventilation, air enters the lungs so that the blood takes in its oxygen and carries away the carbon dioxide (CO2) from the cells.

A healthy person, at rest, has a respiratory rate of 12 to 18 inspirations per minute, with regular respiratory movements.

The apnea is a disease that some people who habitually snore, where breathing stops occur (apneas) between inspiration and expiration. It does not let them rest during sleeping hours and they are drowsy during the day.

Blood pressure

The  blood pressure is the force exerted by the blood on the walls of blood vessels. The blood pressure depends on several factors:

  • Pumping force of the heartIt depends on age, physical exercise and emotional state.
  • Amount of blood expelled in each beat. If the pumped volume is large, the blood pressure on the arterial walls is higher. It depends on physical exercise, type of diet, age, etc.
  • Elasticity of the vessels. If they are very elastic, do not have cholesterol plaques, etc., the blood pressure will be lower.

Blood pressure is given with two values:

  • Systolic pressure, better known as "the maximum" or "the high". Pressure exerted by the blood on the arterial walls when it leaves the heart, passes into the arteries and deforms them.
  • Diastolic pressure, known as "the minimum" or "the low". Pressure exerted by the blood on the arterial walls when the heart relaxes and the blood empties the arteries passing towards the arterioles and veins.

Normal blood pressure values would be between 120-140 millimeters of mercury for systolic pressure (maximum) and between 70-90 millimeters of mercury for diastolic pressure (minimum). If the person has higher blood pressure values, the person is said to suffer from hypertension or high blood pressure. If they are lower values, hypotension or low blood pressure.

Other indicators

In addition to vital signs, there are other parameters that can inform us about our state of health:

  • Weight: It can indicate a disease related to eating. It depends on the size, sex, age and constitution. We must weigh ourselves on an empty stomach, barefoot and without clothes.
  • Vital capacity: Indicates the maximum volume of air that can be exchanged in a single lung ventilation (inspiration and expiration).
  • CBC: The analysis of blood shows the number of blood cells and the chemical composition of the blood plasma. They may indicate some alteration.
  • Urinalysis: Indicates the chemical composition of urine, detecting if there is any foreign substance or if the results obtained are out of the ordinary.


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