Blood pressure is the pressure exerted by the blood on the walls of the blood vessels. Unless indicated otherwise, blood pressure is understood to mean arterial blood pressure, i.e., the pressure in the large arteries, such as the brachial artery (in the arm). The pressure of the blood in other vessels is lower than the arterial pressure. Blood pressure values are universally stated in millimetres of mercury (mm Hg), and are always given relative to atmospheric pressure—the absolute pressure of the blood in an artery with mean arterial pressure stated as 100 mm, on a day with atmospheric pressure of 760 mm, is 860 mm.
The systolic pressure is defined as the peak pressure in the arteries during the cardiac cycle; the diastolic pressure is the lowest pressure (at the resting phase of the cardiac cycle). The mean arterial pressure and pulse pressure are other important quantities.
Typical values for a resting, healthy adult are approximately 120 mmHg systolic and 80 mmHg diastolic (written as 120/80 mmHg), with large individual variations. These measures of blood pressure are not static, but undergo natural variations from one heartbeat to another or throughout the day (in a circadian rhythm); they also change in response to stress, nutritional factors, drugs, or disease.

Measurement
Invasive measurement
Arterial blood pressure (BP) is most accurately measured invasively by placing a cannula into a blood vessel and connecting it to an electronic pressure transducer. This invasive technique is regularly employed in intensive care medicine, anesthesiology, and for research purposes, but it is, rarely, associated with complications such as thrombosis, infection, and bleeding.

Non-invasive measurement
The non-invasive auscultatory (from the Latin for listening) and oscillometric measurements are simpler and quicker, require less expertise in fitting, have no complications, and are less unpleasant and painful for the patient, at the cost of somewhat lower accuracy and small systematic differences in numerical results. These methods actually measure the pressure of an inflated cuff at the points where it just occludes blood flow, and where it just permits unrestricted flow. These are the methods more commonly used for routine examinations and monitoring.

Normal values of blood pressure
Normal ranges for blood pressure in adult humans are:
Systolic between 90 and 135 mmHg (or 90 and 135 Torr, 12 to 18 kPa)
Diastolic between 50 and 90 mmHg (or 50 and 90 Torr, 7 to 12 kPa)
In children the observed normal ranges are lower; in the elderly, they are often higher, largely because of reduced flexibility of the arteries. Clinical trials demonstrate that people who maintain blood pressures at the low end of these pressure ranges have much better long term cardiovascular health and are considered optimal. The principal medical debate is the aggressiveness and relative value of methods used to lower pressures into this range for those who don't maintain such pressure on their own. Elevations, more commonly seen in older people, though often considered normal, are associated with increased morbidity and mortality. The clear trend from double blind clinical trials (for the better strategies and agents) has increasingly been that lower BP is found to result in less disease and better long-term outcomes.

In medicine, blood sugar is a term used to refer to levels of glucose in the blood. Blood sugar concentration, or serum glucose level, is tightly regulated in the human body. Glucose, transported via the bloodstream, is the primary source of energy for the body's cells.
Normally, blood glucose levels stay within narrow limits throughout the day: 4 to 8 mmol/l (70 to 150 mg/dl). Levels rise after meals and are usually lowest in the morning, before the first meal of the day.
Diabetes mellitus is the most prominent disease related to failure of blood sugar regulation.
Though it is called "blood sugar", other sugars besides glucose are found in the blood, like fructose and galactose. However, only glucose levels are regulated via insulin and leptin.

Direct health effects of blood sugar problems
If blood sugar levels drop too low, a potentially fatal condition called hypoglycemia develops. Symptoms may include lethargy, impaired mental functioning, irritability, and loss of consciousness.
If levels remain too high, appetite is suppressed over the short term. Long-term hyperglycemia causes many of the long-term health problems associated with diabetes, including eye, kidney, and nerve damage.

The body mass index (BMI) or Quetelet Index is a measure of the weight of an individual scaled according to height. It is used as a simple means of classifying sedentary individuals according to their body fat content. As a rough guideline for adults a BMI of less than 20 implies underweight, over 25 is overweight, and over 30 is obese. It is calculated by taking the weight of the individual in kilograms and dividing by the square of the height in meters. It was originally developed between 1830 and 1850 by the Belgian polymath, Adolphe Quetelet during the course of developing "social physics".
BMI = weight (kg) / height squared (m2)
or (a version adapted for Imperial units):
BMI = 703 x weight (lb) / height squared (in2)

Recommendations

Body fat percentage is the fraction of the total body mass that is adipose tissue. This index is often used as a means to monitor progress during a diet or as a measure of physical fitness for certain sports, such as body building. It is more accurate as a measure of health than body mass index (BMI) since it directly measures body composition and there are separate body fat guidelines for men and women. However, its popularity is less than BMI because most of the techniques used to measure body fat percentage require equipment and skills that are not readily available.

Recommendations

In medicine, a person's pulse is the throbbing of their arteries as an effect of the heart beat. It can be felt at the neck, at the wrist and other places.

The pulse results from pressure waves moving through the blood vessels, which are pliable; it is not caused by the forward movement of the blood. When the heart contracts, blood are ejected into the aorta and the aorta stretches. At this point the wave of distention (pulse wave) is most pronounced, but relatively slow-moving (3 to 5 m/s). As it travels towards the peripheral blood vessels, it gradually diminishes and becomes faster. In the large arterial branches, its velocity is 7 to 10 m/s; in the small arteries, it is 15 to 35 m/s. The pressure pulse is 15 or more times more rapidly transmitted than the blood flow.

The term pulse is also used, although incorrectly, to denote the frequency of the heart beat, usually measured in beats per minute. In most people, the pulse is an accurate measure of heart rate. Under certain circumstances, including arrhythmias, some of the heart beats are ineffective and the aorta is not stretched enough to create a palpable pressure wave. The pulse is irregular and the heart rate can be (much) higher than the pulse rate. In this case, the heart rate should be determined by auscultation of the heart apex, in which case it is not the pulse. The pulse deficit (difference between heart beats and pulsations at the periphery) should be determined by simultaneous palpation at the radial artery and auscultation at the heart apex.

A normal pulse rate for a healthy adult, while resting, can range from 60 to 90 beats per minute (BPM). During sleep, this can drop to as low as 40 BPM; during strenuous exercise, it can rise as high as 200–220 BPM. Generally, pulse rates are higher in younger persons. A resting heart rate for an infant is as high as or higher than an adult's pulse rate during strenuous exercise.

Besides its rate, the pulse has other qualities which reflect the state of the cardiovascular system, such as its rhythm, fullness and the shape of the pulse wave. Certain diseases cause characteristic changes in these qualities. The absence of a pulse at the temple of the skull can be a sign of giant cell arteritis; absent or decreased pulses in the limbs may indicate peripheral artery occlusive disease.

Pulses are manually palpated with fingers or thumb. When palpating the carotid artery, the femoral artery or the brachial artery, the thumb may be used. However, the thumb has its own pulse which can interfere with detecting the patient's pulse at other points, where two or three fingers should be used. Fingers or thumb must be placed near an artery and pressed gently against a firm structure, usually a bone, in order to feel the pulse.

Common pulse points
radial pulse - located on the thumb side of the wrist.
ulnar pulse - located on the little finger side of the wrist.
carotid pulse - located in the neck.
brachial pulse - located between the biceps and triceps, on the medial side of the elbow cavity.
femoral pulse - located in the thigh.
popliteal pulse - located behind the knee in the popliteal fossa.
dorsalis pedis pulse - located on top of the foot.
tibialis posterior pulse - located in the back of the ankle behind the medial malleolus.
temporal pulse - located on the temple directly in front of the ear.

An electrocardiogram (ECG or EKG, abbreviated from the German Elektrokardiogramm) is a graphic produced by an electrocardiograph, which records the electrical voltage in the heart in the form of a continuous strip graph. It is the prime tool in cardiac electrophysiology, and has a prime function in screening and diagnosis of cardiovascular diseases.

Uses

The ECG has a wide array of uses:
Determine whether the heart is performing normally or suffering from abnormalities (eg. extra or skipped heartbeats - cardiac arrhythmia).
May indicate acute or previous damage to heart muscle (heart attacks) or ischaemia of heart muscle (angina).
Can be used for detecting potassium, calcium, magnesium and other electrolyte disturbances.
Allows the detection of conduction abnormalities (heart blocks and in bundle branch blocks).
As a screening tool for ischaemic heart disease during an exercise tolerance test.
Can provide information on the physical condition of the heart (eg: left ventricular hypertrophy, mitral stenosis).
Can suggest non-cardiac disease (e.g. pulmonary embolism, hypothermia)

Electroencephalography is the neurophysiologic measurement of the electrical activity of the brain by recording from electrodes placed on the scalp or, in special cases, on the cortex. The resulting traces are known as an electroencephalogram (EEG) and represent so-called brainwaves. This device is used to assess brain damage, epilepsy and other problems. In some jurisdictions it is used to assess brain death. EEG can also be used in conjunction with other types of neuroimaging.
Neuroscientists and biological psychiatrists use EEGs to study the function of the brain by recording brainwaves during controlled behavior of human volunteers and animals in lab experiments. Theories to explain sleep often rely on EEG patterns recorded during sleep sessions. In addition, the procedure is used clinically to assist in the diagnosis of epilepsy.

Wave types
Delta is the frequency range up to 4 Hz and is often associated with the very young and certain encephalopathies and underlying lesions. It is seen in stage 3 and 4 sleep.
Theta is the frequency range from 4 Hz to 8 Hz and is associated with drowsiness, childhood, adolescence and young adulthood. This EEG frequency can sometimes be produced by hyperventilation. Theta waves can be seen during hypnagogic states such as trances, hypnosis, deep day dreams, lucid dreaming and light sleep and the preconscious state just upon waking, and just before falling asleep.
Alpha (Berger's wave) is the frequency range from 8 Hz to 12 Hz. It is characteristic of a relaxed, alert state of consciousness and is present by the age of two years. Alpha rhythms are best detected with the eyes closed. Alpha attenuates with drowsiness and open eyes, and is best seen over the occipital (visual) cortex. An alpha-like normal variant called mu is sometimes seen over the motor cortex (central scalp) and attenuates with movement, or rather with the intention to move.
Sensorimotor rhythm (SMR) is a middle frequency (about 12–16 Hz) associated with physical stillness and body presence.
Beta is the frequency range above 12 Hz. Low amplitude beta with multiple and varying frequencies is often associated with active, busy or anxious thinking and active concentration. Rhythmic beta with a dominant set of frequencies is associated with various pathologies and drug effects.
Gamma is the frequency range approximately 26–80 Hz. Gamma rhythms appear to be involved in higher mental activity, including perception, problem solving, fear, and consciousness.