THE HUMAN BODY

1. LESSON 5 THE HUMAN BODY

2. Introduction • Body is composed of different organs and tissues working together • Minor injury or illness may damage only a specific body part or function • Serious injury or sudden illness can threaten vital body functions • Understanding human body can help you recognize effects of injuries and illnesses

3. Special terms are used by health care providers for body regions Directional and positional terms used to describe relationship of body structures Body Regions and Directions

4. Body Regions and Cavities • Extremities refers to both arms and legs • Thorax refers to chest area enclosed by the ribs • Thoracic cavity is area inside chest • Abdomen refers to area immediately below thoracic cavity

5. Body Regions and Cavities (continued) • Abdominal cavity includes stomach, intestines, other organs • Pelvis refers to area below abdomen: pelvic bones between hip and lower spine • Pelvic cavity contains bladder and other organs • Spine, or spinal column, refers to bones of neck and back and nerves, or spinal cord, that run through vertebrae

6. Used to describe specific injuries or signs and symptoms Upper and lower quadrants divided by line passing through umbilicus Quadrants based on anatomical position, with face forward and palms facing forward Abdominal Quadrants

7. Directional Terms All positional and directional terms are based on anatomical position: • Right and left refer to patient’s right and left, divided by midline down center of body • Lateral and medial • Anterior and posterior • Proximal and distal • Superior and inferior • Prone and supine

8. Body Systems • Organs have one or more specific functions • The organs that work together for a specific function are called a body system • Body systems are closely interrelated and work together

9. Examples of Interrelated Body Systems • Blood carries oxygen from lungs to body cells • Nerve sensors detect amount of oxygen and carbon dioxide in the blood and speed up or slow down heart beat and breathing to change oxygen level • If body temperature drops, muscles in extremities start shivering to produce heat, which is carried by blood to vital organs

10. Key Body Systems • Most fundamental for life are the respiratory and cardiovascular systems • Body cells need a constant supply of oxygen • Any failure of breathing or blood circulation threatens life within minutes

11. Pathophysiology • “Patho” refers to an abnormality • Understanding what can go wrong in each body system from injury or illness is important for giving emergency care

12. Respiratory System

13. To bring air into lungs To allow oxygen from air to enter blood To remove carbon dioxide from blood into air breathed out (exhaled) This process is called respiration Functions of Respiratory System

14. Respiratory System: Primary Organs

15. The Breathing Process Breathing depends on muscular movements under control of nervous system: • When the diaphragm contracts/moves down, thoracic cavity and lungs expand, pulling air into lungs • Intercostal muscles assist with ventilation • In lungs, oxygen enters blood and carbon dioxide leaves blood • When diaphragm relaxes and moves up, thoracic cavity contracts, and air carrying carbon dioxide flows back out of lungs

16. Emergency Conditions Related to the Respiratory System • Respiration can be affected by different injuries and illnesses • An airway obstruction is blockage of airway preventing air flow • Inadequate oxygenation due to low oxygen, poison gas, lung infection, etc. • A broken rib may puncture a lung, making breathing ineffective • A penetrating injury into lungs may alter lung pressures keeping lungs from filling with air

17. Emergency Conditions Relatedto the Respiratory System (continued) • Poisoning or drug overdose may depress nervous system functions, slowing or stopping breathing • Asthma is a common illness in which airway tissues swell making it hard to breathe • In infants and children, anatomical structures are smaller and airway is more easily obstructed • Uncorrected respiratory problem is the primary cause of cardiac arrest in infants and children

18. Cardiovascular System

19. Functions of the Cardiovascular System • To transport oxygen and nutrients in the blood to all parts of body • To remove carbon dioxide and other wastes

20. Cardiovascular System: Primary Organs • Heart • Blood • Blood vessels

21. The Blood • Red blood cells carry oxygen to body cells • White blood cells are an important part of the immune system • Plasma is the liquid substance of blood • Blood also carries glucose to body cells for energy • Blood clotting factors help control bleeding

22. Pathway of Blood Ventricles pump blood through 2 loops or cycles in body: • Right ventricle pumps blood to lungs picking up oxygen and releasing carbon dioxide • Blood returns to left atrium, from which it moves to left ventricle • Left ventricle pumps oxygenated blood into body to release oxygen and pick up carbon dioxide for removal • Blood returns to right atrium, moving to right ventricle to be pumped again to lungs

23. Pulses • Pulsing blood pressure changes occur in arteries that can be felt as pulse • Commonly measured pulses: • Carotid • Femoral • Radial • Brachial

24. Heart rate, measured as pulse, is affected by many factors Average resting heart rate in adult males is 6472 beats/minute; in females, 7280 beats/minute Heart rate of infants and children is higher With exercise, fever or emotional excitement, heart rate increases to meet body’s greater need for oxygen Heart Rate

25. Emergency Conditions Related tothe Cardiovascular System • Cells begin to die in vital organs such as brain after only a few minutes without oxygen • Shock is a life-threatening condition that occurs when vital body organs are not receiving enough oxygen • Oxygen delivery diminished by injury or illness affecting heart, blood, or blood vessels • Severe bleeding leaves not enough blood in circulation to provide body with oxygen • Arterial bleeding is most severe  blood may spurt out under pressure, leading to life-threatening shock

26. Emergency Conditions Related to the Cardiovascular System(continued) • Bleeding from veins generally slower but can still be serious or life threatening if it continues • Capillary bleeding usually minor and stops by itself as blood clots • Problems affecting blood volume (bleeding, repeated vomiting or diarrhea, or burns) affect circulation • Blood vessel problems (inability to constrict) cause poor circulation; may occur with spinal cord injuries, infection or anaphylaxis

27. Cardiovascular Illnesses • Stroke is problem involving arteries in brain; reduced circulation may cause mental and physical impairments • If heart muscle does not receive enough oxygenated blood because of blocked cardiac arteries, cardiac muscle tissue may die • The heart may stop (cardiac arrest) • Dysrhythmia (or arrhythmia), an irregular heartbeat, may reduce heart’s pumping ability • Fibrillation, a serious dysrhythmia, common after heart attack • Any problem affecting the heart rate or strength of contractions can cause poor circulation and shock (poisoning, heart disease)

28. Musculoskeletal System

29. Functions of the Musculoskeletal System • Skeletal system provides shape and support for body as a whole • Muscles act on bones, allowing for movement • Groups of bones protect vital internal organs: • Ribs protect heart and lungs • Skull protects brain • Vertebrae protect spinal cord • Pelvic bones protect bladder and other organs

30. Musculoskeletal System: Primary Organs • Bones • Muscles • Tendons • Ligaments

31. Types of Muscles • Skeletal muscles create body movements and also produce heat  usually under voluntary control • Smooth muscles such as in the esophagus and blood vessels are usually under involuntary control • Cardiac muscle is also involuntary but is unique in that the heart produces its own stimuli to contract

32. Emergency Conditions Related tothe Musculoskeletal System • Most fractures are not life-threatening • In a dislocation, one or more bones move out of position in joint • Sprain is stretching and tearing ofligaments and other structures in a joint • Strain is muscle or tendon tear usually caused by overexerting muscle

33. Musculoskeletal InjuriesAssociated with Other Injuries • Vertebral fractures likely to injure spinal cord and cause nervous system damage • Fractures of femur often cause much soft-tissue damage, bleeding and femoral artery damage • Pelvis fracture may damage bladder/other organs in pelvic cavity or femoral arteries • A skull fracture may cause brain damage

34. Nervous System

35. Nervous System: Primary Functions • Sensory receptors gather information about environment and send to brain • Brain integrates and analyzes information • Nerve signals from brain lead to actions throughout body to accomplish tasks or maintain homeostasis

36. Nervous System: Primary Organs • Brain • Spinal cord • Sensory receptors • Nerves

37. Emergency Conditions Related to the Nervous System • Head and spinal injuries • Serious or life threatening • Injury to part of brain or stroke • May destroy or impair one or more functions • Damage to spinal cord • Complete loss of function to body area or paralysis

38. Emergency Conditions Related to the Nervous System (continued) • Altered mental status from: • Head injuries • Any injury causing decreased oxygenation • Sudden illness (e.g., stroke, seizure, diabetes) • Severe infection or fever • Poisoning or drug overdose

39. Nervous System Effects Associated with Other Injuries • Injuries and some illnesses also affect nervous system • Pain results from damage to nerve fibers in many areas of body • Crushing pain in chest may be caused by heart attack • Abdominal pain that begins in umbilicus and settles into lower abdomen on right side may be a sign of appendicitis • Pain should always be taken seriously

40. Other Body Systems

41. Integumentary System: Primary Functions • Protect body • Help regulate body temperature • Help prevent water loss • Sensation (e.g., touch, pressure, pain, temperature)

42. Emergency Conditions Related to the Integumentary System • Cuts and scrapes • Bleeding • Openings in skin • Allow pathogens into body • Heat and chemical burns • Loss of body heat • Loss of body fluid

43. Importance of Skin Condition • Skin often reveals important information about body condition • Skin of hypothermia patient • Skin of heatstroke patient • Skin of patient with low blood oxygen levels • Skin of patient in shock • Many sudden illnesses cause sweating and skin color changes (flushed or pale)

44. Gastrointestinal System • Digests food and extracts nutrients • Organs easily injured by traumatic forces

45. Emergency Conditions Related to the Gastrointestinal System • Abdominal cavity not protected by bones, gastrointestinal organs may be easily injured by traumatic forces • In closed injury, pain or tenderness along with swollen, rigid abdomen may suggest internal injury • In an open wound, internal organs may be exposed, raising risk of infection • Ingested poison is absorbed in the same manner as nutrients from food and enters the bloodstream to affect body • Various illnesses may cause vomiting or diarrhea, which can lead to dehydration especially in infants • Vomiting blood is likely sign of a serious internal injury

46. Removes metabolic wastes from body in urine Helps body maintain fluid and electrolyte balances Functions of the Urinary System

47. Blood transports wastes to kidneys Kidneys filter wastes and produce urine Urinary System: Primary Organs

48. Emergency Conditions Related to the Urinary System • Traumatic injury may damage organs • Look for blood in urine • Health problems • May cause change in urination • Dehydration • Lack of urination

49. Female Produces eggs Supports and nurtures fetus in uterus Childbirth Lactation Male Produces and transports sperm Reproductive System

50. Emergency Conditions Related to the Reproductive System • Abdominal injuries may damage genitals or reproductive organs – such wounds may require special care, including concern for patient’s privacy • Complications may develop in pregnancy • Childbirth may occur unexpectedly away from a health care facility