Oxygen (O₂) is a gas. It has no taste, odor, or color. It is a basic need required for life. Death occurs within minutes if breathing stops. Brain damage and serious illness can occur without enough oxygen. Illness, surgery, and injuries affect the amount of oxygen in the blood and cells.

You assist in the care of persons with oxygen needs. You must give safe and effective care.

Factors affecting oxygen needs

The respiratory and circulatory systems must function properly for cells to get enough oxygen. Any disease, injury, or surgery involving these systems affects the intake and use of oxygen. Body systems depend on each other. Altered function of any system (for example, the nervous, musculo-skeletal, or urinary system) affects oxygen needs. Oxygen needs are affected by:

• Respiratory system. Structures must be intact and function properly. An open (patent) airway is needed. Alveoli (air sacs) must exchange O₂ and carbon dioxide (CO₂).

• Circulatory system. Blood must flow to and from the heart. Narrowed vessels affect blood flow. Capillaries and cells must exchange O₂ and CO₂.

• Red blood cell count. Red blood cells (RBCs) contain hemoglobin. Hemoglobin picks up O₂ in the lungs and carries it to the cells. The bone marrow must produce enough RBCs. Poor diet, chemotherapy, and leukemia affect bone marrow function. Blood loss also reduces the number of RBCs.

• Nervous system. Nervous system diseases and injuries can affect respiratory muscles. Breathing may be difficult or impossible. Brain damage affects respiratory rate, rhythm, and depth. Narcotics and depressant drugs affect the brain. They slow respirations. O₂ and CO₂ blood levels also affect brain function. Respirations increase to bring in more O₂. They also increase to rid the body of excess CO₂.

• Aging. Respiratory muscles weaken. Lung tissue is less elastic. Strength for coughing decreases. The person must cough and remove secretions from the upper airway. Otherwise, pneumonia (inflammation and infection of the lung) can develop. Respiratory complications are risks after surgery.

• Exercise. O₂ needs increase with exercise. Respiratory rate and depth increase to bring in O₂. Persons with heart and respiratory diseases may have enough oxygen at rest. However, even slight activity can increase O₂ needs. Their bodies may not be able to bring in O₂ and carry it to the cells.

• Fever. O₂ needs increase. Respiratory rate and depth increase to meet the body’s needs.

• Pain. O₂ needs increase. Respirations increase to meet this need. Chest and abdominal injuries and surgeries often involve respiratory muscles. It hurts to breathe in and out.

• Drugs. Some drugs depress the respiratory center in the brain. Respiratory depression means slow, weak respirations at a rate of fewer than 12 per minute. Respirations are too shallow to bring enough O₂ into the lungs. Respiratory arrest is when breathing stops. Narcotics (morphine, Demerol, and others) can have these effects. (Narcotic comes from the Greek word narkoun. It means stupor or to be numb.) In safe amounts, these drugs relieve severe pain. Substance abusers are at risk for respiratory depression and respiratory arrest from drug over-doses.

• Smoking. Smoking causes lung cancer and chronic obstructive pulmonary disease (COPD). It is a risk factor for coronary artery disease.

• Allergies. An allergy is a sensitivity to a substance that causes the body to react with signs and symptoms. Runny nose, wheezing, and congestion are common. Mucous membranes in the upper airway swell. With severe swelling, the airway closes. Shock and death are risks. Pollens, dust, foods, drugs, insect bites, and cigarette smoke often cause allergies. Chronic bronchitis and asthma are risks.

• Pollutant exposure. A pollutant is a harmful chemical or substance in the air or water. Examples are dust, fumes, toxins, asbestos, coal dust, and sawdust. They damage the lungs. Pollutant exposure occurs in home, work, and public settings.

• Nutrition. The body needs iron and vitamins (vitamin B₁₂, vitamin C, and folate) to produce RBCs.

• Alcohol. Alcohol depresses the brain. Excessive amounts reduce the cough reflex and increase the risk of aspiration. Obstructed airway and pneumonia are risks from aspiration.

Altered respiratory function

Respiratory function involves three processes. Respiratory function is altered if even one process is affected.

• Air moves into and out of the lungs.

• O₂ and CO₂ are exchanged at the alveoli.

• The blood carries O₂ to the cells and removes CO₂ from them.

Hypoxia

Hypoxia means that cells do not have enough (hypo) oxygen (oxia). Without enough oxygen, cells cannot function properly. Anything affecting respiratory function can cause hypoxia. The brain is very sensitive to inadequate O₂. Restlessness is an early sign. So are dizziness and disorientation. Report the signs and symptoms in Box 28-1 at once.

Hypoxia threatens life. All organs need oxygen to function. Oxygen is given. The cause of hypoxia is treated.

Abnormal respirations

Normal adult respirations are 12 to 20 per minute. They are quiet, effortless, and regular. Both sides of the chest rise and fall equally. These breathing patterns are abnormal (Fig. 28-1):

• Tachypnea—rapid (tachy) breathing (pnea). Respirations are more than 20 per minute. Fever, exercise, pain, pregnancy, airway obstruction, and hypoxemia are common causes. Hypoxemia is a reduced amount (hypo) of oxygen (ox) in the blood (emia).

• Bradypnea—slow (brady) breathing (pnea). Respirations are fewer than 12 per minute. Drug over-dose and nervous system disorders are common causes.

• Apnea—lack or absence (a) of breathing (pnea). It occurs in sudden cardiac arrest and respiratory arrest. Sleep apnea is another type of apnea.

• Hypoventilation—respirations (ventilation) are slow (hypo), shallow, and sometimes irregular. Lung disorders affecting the alveoli are common causes. Pneumonia is an example. Other causes include obesity, airway obstruction, and drug side effects. Nervous system and musculo-skeletal disorders affecting the respiratory muscles also are causes.

• Hyperventilation—respirations (ventilation) are rapid (hyper) and deeper than normal. Causes include asthma, emphysema, infection, fever, nervous system disorders, hypoxia, anxiety, pain, and some drugs.

• Dyspnea—difficult, labored, or painful (dys) breathing (pnea). Heart disease and anxiety are common causes.

• Cheyne-Stokes respirations—respirations gradually increase in rate and depth. Then they become shallow and slow. Breathing may stop (apnea) for 10 to 20 seconds. Drug over-dose, heart failure, renal failure, and brain disorders are common causes. Cheyne-Stokes are common when death is near.

• Orthopnea—breathing (pnea) deeply and comfortably only when sitting (ortho). Common causes are emphysema, asthma, pneumonia, angina, and other heart and respiratory disorders.

• Biot’s respirations—rapid and deep respirations followed by 10 to 30 seconds of apnea. They occur with nervous system disorders.

• Kussmaul respirations—very deep and rapid respirations. They signal diabetic coma.

Fig. 28-1 Some abnormal breathing patterns. (Modified from Talbot L, Meyers-Marquardt M: *Pocket guide to critical care assessment,* ed 3, St Louis, 1997, Mosby.)

Assisting with assessment and diagnostic tests

Altered respiratory function may be an acute or chronic problem. Report your observations promptly and accurately (Box 28-2). Quick action is needed to meet the person’s oxygen needs. Measures are taken to correct the problem and to prevent it from becoming worse.

Box 28-2

Signs and Symptoms of Altered Respiratory Function

• Hypoxia: signs and symptoms of (see Box 28-1)

• Breathing pattern: abnormal

• Shortness of breath or complaints of being “winded” or “short-winded”

• Cough (note frequency and time of day)

• Dry and hacking

• Harsh and barking

• Productive (produces sputum) or non-productive

• Sputum (mucus from the respiratory system)

• Color: clear, white, yellow, green, brown, or red

• Odor: none or foul odor

• Consistency: thick, watery, or frothy (with bubbles or foam)

• Hemoptysis: bloody (hemo) sputum (ptysis means to spit); note if the sputum is bright red, dark red, blood-tinged, or streaked with blood

• Respirations: noisy

• Wheezing

• Wet-sounding

• Crowing sounds

• Chest pain (note location)

• Constant or comes and goes

• Person’s description (stabbing, knife-like, aching)

• What makes it worse (movement, coughing, yawning, sneezing, sighing, deep breathing)

• Cyanosis (bluish color)

• Vital signs: changes in

• Position

• Sitting upright

• Leaning forward or hunched over a table

See Focus on Communication: Assisting With Assessment and Diagnostic Tests.

FOCUS ON COMMUNICATION

Assisting With Assessment and Diagnostic Tests

The questions you ask the person aid the nurse in the assessment step of the nursing process. For example:

• “Do you need more pillows?”

• “Do you want the head of your bed raised more?”

• “How often are you coughing?”

• “Are you coughing anything up?”

• “Please use a tissue when you cough up mucus, then put on your signal light. The nurse needs to observe the mucus.”

The doctor orders tests to find the cause of the problem. These tests are commonly done in hospitals:

• Chest x-ray (CXR). An x-ray is taken of the chest to study lung changes.

• Lung scan. The lungs are scanned to see what areas are not getting air or blood. The person inhales radioactive gas. Radioactive means to give off radiation. A radioisotope is injected into a vein. A radioisotope is a substance that gives off radiation. Lung tissue getting air and blood flow “take up” the substance.

• Bronchoscopy. A scope (scopy) is passed into the trachea and bronchi (broncho). Airway structures are checked for bleeding and tumors. Tissue samples (biopsies) are taken. Or mucous plugs and foreign objects are removed. The person is NPO (non per os; nothing by mouth) for 6 to 8 hours before the procedure. This reduces the risks of vomiting and aspiration. An anesthetic is given. After the procedure, the person is NPO and observed carefully until the gag and swallow reflexes return. This can take about 2 hours.

• Thoracentesis. The pleura (thora) is punctured. Air or fluid is removed (centesis) from it. The doctor inserts a needle through the chest wall into the pleural sac (Fig. 28-2, p. 446). Injury or disease can cause the sac to fill with air, blood, or fluid. Anti-cancer drugs can be injected into the pleural sac. The procedure takes a few minutes. Vital signs are taken. Then a local anesthetic is given. The person sits up and leans forward. He or she must not talk, cough, or move suddenly. Afterward a dressing is applied to the puncture site. Vital signs are taken. A chest x-ray is taken to detect lung damage. The person is observed for shortness of breath, dyspnea, cough, sputum, chest pain, cyanosis, vital sign changes, and other respiratory signs and symptoms.

• Pulmonary function tests. These measure the amount of air moving into and out of the lungs (volume). They also measure how much air the lungs can hold (capacity). The person takes as deep a breath as possible. Using a mouthpiece, the person blows into a machine (Fig. 28-3, p. 446). The tests help assess the risk for lung diseases or post-operative lung complications. They also measure the progress of lung disease and its treatment. Fatigue is common after the tests. The person needs to rest.

• Arterial blood gases (ABGs). A radial, femoral, or brachial artery is punctured to obtain arterial blood. Laboratory tests measure the amount of O₂ in the blood. Bleeding from the artery must be prevented. Pressure is applied to the artery for at least 5 minutes after the procedure. Pressure is applied longer if there are blood-clotting problems.