What is Phlebotomy

Phlebotomy 

What is phlebotomy?

The term phlebotomy is derived from the Greek words, phlebo, which relates to veins, and tomy, which relates to cutting. In ancient times, phlebotomy was practiced to withdraw blood using various means, including knives, crude lancets, leeches, blood cups or bowls, pumps, and glass syringes. In some cultures, phlebotomy was thought

to cleanse or purify the body and/or get rid of unwanted spirits. However, today, modern phlebotomy equipment and practices are very advanced. The current definition of phlebotomy can be summarized as the incision of a vein for collecting a blood sample (a portion of blood removed that is small enough so as not to cause harm) for laboratory testing or other therapeutic purposes (e.g., blood donations). Synonymous words are venesection or venesection, and the phlebotomist, or blood collector, is the individual who performs phlebotomy.

Anatomy and Physiology Overview

The design of the human body is elaborate and sophisticated. Anatomy is the study of its physical structure and physiology is the study of its functional processes. A human body can be divided into eight structural levels:

1. Atoms (carbon, hydrogen, oxygen, nitrogen, iron, etc.)
2. Molecules (chemical constituents)
3. Organelles or small structures within cells
4. Cells (the basic living units of all plants and animals)
5. Tissues (groups of similar cells)
6. Organs (two or more tissues)
7. Organ systems (groups of organs)
8. The organism (the human body) itself Trillions of cells make up each individual, Similar groups of cells are

combined into tissues, such as muscles or nerves, and tissues are combined into systems, such as the circulatory or reproductive system. These organ systems work simultaneously to serve the needs of the body. No one system works independently of the others.

INTEGUMENTARY SYSTEM

Structure and Function 

The integumentary system consists of:

• Skin
• Hair
• Sweat glands (sudoriferous) and oil glands (sebaceous)
• Teeth
• Fingernails

It serves for protection and regulatory functions such as insulation, thermal regulation, excretion, and the production of vitamin D. Skin is the largest organ of the body (covering about 3,000 square inches and weighing about 6 pounds), protecting the deeper tissues by providing a barrier to entering microorganisms and foreign bodies and by protecting from hazardous exposures such as heat and cold. The skin also prevents water loss or allows for perspiration as needed by the body during exercise or fever or due to weather conditions. Sebaceous glands in the skin produce oils for hair and skin protection, and sweat glands produce perspiration, which helps

cool the body as needed and eliminates some waste. Melanin in the skin provides skin color and protects underlying tissues from absorbing ultraviolet rays. Ultraviolet light stimulates production of inactive vitamin D in the skin. The liver and kidneys then activate vitamin D so that it is beneficial to the body. Other functions of the skin are to store fat in the layers next to the underlying tissues and to allow an individual to experience sensations such as touch, temperature, pain, and pressure.

Hair on the head provides protection by acting as a heat insulator; eyebrows keep perspiration out of the eyes; eyelashes protect eyes from foreign objects; and hairs in the nasal passages filter out dust and harmful microorganisms. Likewise, fingernails protect the tips of the hands. Teeth aid in breaking up food to begin the digestive process.

Disorders of the Integumentary System

• Bacterial infections, such as acne and impetigo (caused by Staphylococcus aureus)
• Decubitis ulcers, also known as bedsores or pressure ulcers, are caused by partial blood flow obstruction to the soft tissue as a result of inactivity or constant pressure or friction to an area of the skin. Common in bedridden patients or those confined to a wheelchair; affected sites are the hips, coccyx, elbows, knees, ankles, etc.
• Viral infections, such as fever blisters or cold sores
• Rubeola, rubella, chickenpox, and herpes zoster (shingles)
• Fungal infections, such as ringworm and athlete’s foot
• Allergic reactions, such as urticaria
• Dermatitis (inflammation of the dermal layers of skin), eczema (red, itchy, skin inflammations), and psoriasis (red, scaly patches on skin)
• Insect bites and burns
• Skin cancers, such as malignant melanoma