Thermometer
Do not use an electronic thermometer and a simple mercury or alcohol one. The normal human temperature is between 35.5 and 36.8⁰C. Maintaining a temperature of about 37.0 - 37.3⁰C for days means you have inflammation. Lab test your blood for deviation in the ESR (Erythrocyte Sedimentation Rate). If it is increased this is confirmation for the presence of an inflammatory process. Inflammatory process is caused by numerous reasons - from the the harmless one to the most dangerous one. An example of a consistently high sedimentation rate but absolutely normal temperature is for example the presence of bacteria into the renal pelvis in women which in turn can be a chronic condition continuing for decades without creating a health hazard.
Allergic conditions cause increased sedimentation rate for months. Colds also raise the sediment but only up to 10 days after full recovery of the illness took place.
Blood pressure monitor
Measures the values of the heart rate, systolic and diastolic blood pressure. Systolic is called the pressure value that the heart creates in its contraction at the time of pumping blood to the aorta and diastolic is the pressure when the heart relaxes when it is being filled with blood through vena cava (superior and inferior). Accurate measurement of blood pressure is obtained using apparatus with a hand pump and stethoscope but more expensive electronic analogues give the same accuracy values which is a great convenience when you need to measure your own blood pressure being alone at home for example.
Why is it so important to regularly measure this indicator? When blood pressure is high or low our body is experiencing stress of many different types progressively leading to severe chronic diseases so measure your blood pressure regularly. If after measuring commonly you do not have high or low values it is enough to control your blood pressure 2 - 3 times a week but if you are hypertensive or hypotonic it is imperative measurements to be carried out every day in order to correct the water-salt balance in your body which is explained in details in paragraph "Water - the best of diuretics".
Glucometer
Measures the content of glucose is blood. The measurement is done in the morning immediately after getting up on an empty stomach as with the lancing device that is part of the measuring set prick the tip of one of your fingers and place a drop of blood on the measuring strip. If you do not have such device for monitoring at home it is needed to go to a medical laboratory where venous blood for testing will be taken from you. The values for the lower and upper limit of blood glucose (taken capillary or venous) are indicated in paragraph "Laboratory Tests Range Values".
Pulse Oximeter and Heart Rate Monitor
Measures the heart rate and oxygen saturation of hemoglobin. It should be placed on one of the fingers. If your saturation is within 94 - 99% and your heart rate at rest is 60 - 80 beats per minute (BPM) then you have an excellent level of binding of oxygen to hemoglobin in red blood cells in your lungs and your heart works without undue dynamics. When you lie down saturation and pulse fall. It is common your pulse during sleep to fall to 50 - 55 beats/min and when you just lie on the bed or sit on a chair to be between 55 - 65 beats/min. Usually respiratory rate at rest (the number of breaths per minute) for an adult should be around 16. If your pulse frequently falls below 60 beats/min in the active part of the day when you're not lying it is necessary to visit a cardiologist for medical examination.