LEARNING OBJECTIVE: Recall basic life support techniques for upper airway obstruction, respiratory failure, and cardiac arrest.

Basic life support is the emergency technique for recognizing and treating upper airway obstruction and failures of the respiratory system and heart. The primary emphasis should be on the ABCs of basic life support: maintaining an open airway to counter upper airway obstruction; restoring breathing to counter respiratory arrest; and restoring circulation to counter cardiac arrest.


The assurance of breathing takes precedence over all other emergency measures. The reason for this is simple: If a person cannot breathe, he cannot survive.

Many factors may cause a person’s airway to become fully or partially obstructed. A very common cause of obstruction with both adults and children is improperly chewed food that becomes lodged in the airway (an event commonly referred to as a “cafe coronary”). Additionally, children have a disturbing tendency to swallow foreign objects while at play. Another cause for upper airway obstruction occurs during unconsciousness, when the tongue may fall back and block the pharynx (fig. 4-1). When the upper airway is obstructed, the heart will normally continue to beat until oxygen deficiency becomes acute. Periodic checks of the carotid artery must be made to ensure that circulation is being maintained.

Partial Airway Obstruction

The signs of partial airway obstruction include unusual breath sounds, cyanosis, or changes in breathing pattern. Conscious patients will usually make clutching motions toward their neck, even when the obstruction does not prevent speech. Encourage conscious patients with apparent partial obstructions to cough. If the patient is unable to cough, begin to treat the patient as if this were a complete obstruction. (This also applies to patients who are cyanotic.)

Figure 4-1.—Tongue blocking airway.

Complete Airway Obstruction

Conscious patients will attempt to speak but will be unable to do so. Nor will they be able to cough. Usually, patients will display the universal distress signal for choking by clutching their neck. The unconscious patient with a complete airway obstruction exhibits none of the usual signs of breathing: rise and fall of the chest and air exchange through the nose and/or mouth. A complete blockage is also indicated if a correctly executed attempt to perform artificial ventilation fails to instill air into the lungs.

Opening the Airway

Many problems of airway obstruction, particularly those caused by the tongue, can be corrected simply by repositioning the head and neck. If repositioning does not alleviate the problem, more aggressive measures must be taken.


When a patient is unresponsive, you must determine if he is breathing. This assessment requires the patient to be positioned properly with the airway opened.

Before repositioning patients, it is imperative that you remember to check them for possible spinal injuries. If there is no time to immobilize these injuries and the airway cannot be opened with the victim in the present position, then great care must be taken when repositioning. The head, neck, and back must be moved as a single unit. To do this, adhere to the following four steps (see figure 4-2).

Figure 4-2.—The four steps to reposition the victims of spinal injuries.

Step 1—Kneel to the side of the victim in line with the victim’s shoulders, but far enough away so that the victim’s body will not touch yours when it is rolled toward you. Straighten the victim’s legs, gently but quickly. Then move the victim’s closer arm along the floor until it reaches straight out past the head.

Step 2—Support the back of the victim’s head with one hand while you reach over with the other hand to grasp under the distant armpit.

Step 3—Pull the patient toward you while at the same time keeping the head and neck in a natural straight line with the back. Resting the head on the extended arm will help you in this critical task.

Step 4—Roll the patient onto his back and reposition the extended arm.

Once the patient is supine with the arms alongside the body, you should position yourself at the patient’s side. By positioning yourself at the patient’s side, you can more easily assess whether the patient is breathing. If the patient is not breathing, you are already positioned to perform artificial respirations (also referred to as rescue breathing) and chest com­pressions.

Either one of two maneuvers—the head tilt-chin lift maneuver or the jaw-thrust maneuver—may be used to open an obstructed airway. When performing these maneuvers, you may discover foreign material or vomitus in the mouth that needs to be removed. Do not spend very much time to perform this task. Liquids or semiliquids should be wiped out with the index and middle finger covered by a piece of cloth. Solid material should be extracted with a hooked index finger.

HEAD TILT-CHIN LIFT MANEUVER.—The head tilt-chin lift maneuver is the primary method used to open the airway. To perform the head tilt-chin lift maneuver, place one of your hands on the patient’s forehead and apply gentle, firm, backward pressure using the palm of your hand. Place the fingers of the other hand under the bony part of the chin. Lift the chin forward and support the jaw, helping to tilt the head back. See figure 4-3. This maneuver will lift the patient’s tongue away from the back of the throat and provide an adequate airway.

Figure 4-3.—Head tilt-chin lift maneuver.

PRECAUTIONS: When performing the head tilt-chin lift maneuver, do not press too deeply into the soft tissue under the chin. Undue pressure in this location may obstruct the airway. In addition, make sure the mouth is kept open so exhalation and inhalation are not hindered.

JAW-THRUST MANEUVER.—The jaw-thrust maneuver is considered an alternate method for opening the airway. This maneuver is accomplished by kneeling near the top of the victim’s head, grasping the angles of the patient’s lower jaw, and lifting with both hands, one on each side. This will displace the mandible (jawbone) forward while tilting the head backward. Figure 4-4 illustrates the jaw-thrust maneuver. If the lips close, retract the lower lip with your thumb. If mouth-to-mouth breathing is necessary, close the nostrils by placing your cheek tightly against them.

Figure 4-4.—Jaw-thrust maneuver.


The jaw-trust technique without head tilt is considered the safest approach to opening the airway of patients with suspected neck injuries because it usually can be done without extending the neck.

Foreign-Body Airway Obstruction Management

Foreign-body airway obstruction should be considered in any victim—especially a younger victim –who suddenly stops breathing, becomes cyanotic, or loses consciousness for no apparent reason.

The Heimlich maneuver (subdiaphragmatic abdominal thrusts) is recommended for relieving foreign-body airway obstruction. By elevating the diaphragm, the Heimlich maneuver can force air from the lungs to create an artificial cough intended to expel a foreign body obstructing the airway. Each individual thrust should be administered with the intent of relieving the obstruction. It may be necessary to repeat the thrust several times to clear the airway. Five thrusts per sequence is recommended.

When you perform this maneuver, you should guard against damage to internal organs, such as rupture or laceration of abdominal or thoracic viscera. To minimize this possibility, your hands should never be placed on the xiphoid process of the sternum or on the lower margins of the rib cage. They should be below this area but above the navel and in the midline.

Regurgitation may occur as a result of abdominal thrusts. Be prepared to position the patient so aspiration does not occur.

HEIMLICH MANEUVER WITH VICTIM STANDING OR SITTING.—To perform the Heimlich maneuver with victim standing or sitting, stand behind the victim, wrap your arms around the victim’s waist, and proceed as follows:

Step 1—Make a fist with one hand.

Step 2—Place the thumb side of the fist against the victim’s abdomen, in the midline slightly above the navel and well below the tip of the xiphoid process.

Step 3—Grasp the fist with the other hand and press the fist into the victim’s abdomen with a quick upward thrust. See figure 4-5.

Figure 4-5.—Administering the Heimlich maneuver to a conscious victim who is standing.

Step 4—Repeat the thrusts and continue until the object is expelled from the airway or the patient becomes unconscious. Each new thrust should be a separate and distinct movement.

HEIMLICH MANEUVER WITH VICTIM LYING DOWN.—To perform the Heimlich maneuver with victim lying down, proceed as follows:

Step 1—Place the victim in the supine position (face up).

Step 2—Kneel astride the victim’s thighs and place heel of one hand against the victim’s abdomen, in the midline slightly above the navel and well below the tip of the xiphoid.

Step 3—Place the second hand directly on top of the first.

Step 4—Press into the abdomen with a quick upward thrust. See figure 4-6.

Figure 4-6.—Administering the Heimlich maneuver to an unconscious victim who is lying down.

If you are in the correct position, you will have a natural mid-abdominal position and are unlikely to direct the thrust to the right or left. A rescuer too short to reach around the waist of an unconscious victim can use this technique. The rescuer can use their body weight to perform the maneuver.

CHEST THRUSTS WITH VICTIM STANDING OR SITTING.—This technique is used only in the late stages of pregnancy or in the markedly obese victim. To perform chest thrusts with victim standing or sitting, proceed as follows:

Step 1—Stand behind the victim, with your arms directly under the victim’s armpits, and encircle the victim’s chest.

Step 2—Place the thumb side of your fist on the middle of the victim’s sternum (breastbone), taking care to avoid the xiphoid process and the margins of the rib cage.

Step 3—Grab your fist with the other hand and perform backward thrust until the foreign body is expelled or the victim becomes unconscious. See figure 4-7.

Figure 4-7.—Administering the chest thrust to a conscious victim who is standing.

CHEST THRUSTS WITH VICTIM LYING DOWN.—Chest thrusts should be used only for victims in the late stages of pregnancy and when the Heimlich maneuver cannot be applied effectively to the unconscious, markedly obese victim. To perform chest thrusts with victim lying down, proceed as follows:

Step 1—Place the victim on his back and kneel close to the victim’s side.

Step 2––Place the heel of your hand on the lower portion of the sternum (in the same manner as you would when performing chest compressions).

Step 3––Deliver each thrust firmly and distinctly, with the intent of relieving the obstruction.

MANUAL REMOVAL OF FOREIGN BODY.—A foreign body can be removed by performing a “finger sweep.” This procedure, however, must be performed on unconscious victims only (though not on seizure victims). To perform a finger sweep, proceed as follows:

Step 1––With the victim’s face up, open the victim’s mouth by grasping both the tongue and lower jaw between the thumb and fingers and lifting the jaw. This action draws the tongue away from the back of the throat and away from a foreign body that may be lodged there. This step alone may partially relieve the obstruction.

Step 2––Insert the index finger of the other hand down along the inside of the cheek and deeply into the throat to the base of the tongue.

Step 3––Use a hooking action to dislodge the foreign body and maneuver it into the mouth so that it can be removed. See figure 4-8.

Figure 4-8.—Finger sweep.

It is sometimes necessary to use the index finger to push a foreign body against the opposite side of the throat to dislodge and remove it. Be careful not to force the object deeper into the airway. If the foreign body comes within reach, grasp and remove it.


The second aspect of basic life support is to restore breathing in cases of respiratory arrest. Failure of the breathing mechanism may be caused by various factors. They include complete airway obstruction, insufficient oxygen in the air, inability of the blood to carry oxygen (e.g., carbon monoxide poisoning), paralysis of the breathing center of the brain, and external compression ofthe body. Respiratory arrest is usually but not always immediately accompanied by cardiac arrest. Periodic checks of the carotid pulse must be made, and you must be prepared to start cardiopulmonary resuscitation (CPR).

Signs of respiratory arrest are an absence of respiratory effort, a lack of detectable air movement through the nose or mouth, unconsciousness, and a cyanotic discoloration of the lips and nail beds.

Determining Breathlessness

Figure 4-9.—Determining breathlessness.

To assess the presence or absence of breathing (fig. 4-9), you should use the following procedures:

Step 1—Place your ear over the patient’s mouth and nose, while maintaining an open airway.

Step 2—While observing the patient’s chest

Recovery Position

If the patient is unresponsive, has no evidence of trauma, and is obviously breathing adequately, place the patient in the “recovery position.” See figure 4-10. In the recovery position, the airway is more likely to remain open, and an unrecognized airway obstruction caused by the tongue is less likely to occur. It is important to continue close observation of the patient who has been placed in the recovery position until he becomes responsive.

Figure 4-10.—A patient in the recovery position.

To place a patient in the recovery position, roll the patient onto his side so that the head, shoulders, and torso move simultaneously without twisting. If the patient has sustained trauma or trauma is suspected, the patient should NOT be moved.

Artificial Ventilation

If a patient is in respiratory arrest, artificial ventilations must be started immediately. Any delay could result in brain damage or death. The purpose of artificial ventilation is to provide air exchange until natural breathing is re-established. Artificial ventilation should be given only when natural breathing has been suspended; it must not be given to a person who is breathing naturally. Do not assume that a person’s breathing has stopped merely because the person is unconscious or has been rescued from water, from poisonous gas, or from contact with an electric wire.

Techniques of artificial ventilation include mouth-to-mouth, mouth-to-nose, mouth-to-stoma, and mouth-to-mask. These techniques as they apply to adult patients are discussed in the following sections.

MOUTH-TO-MOUTH.—Artificial ventilation with the mouth-to-mouth technique is a quick, effective way to provide oxygen to the patient. The exhaled air contains enough oxygen to supply the patient’s needs.

To perform mouth-to-mouth ventilation, the airway must be open. To open the airway, perform the head tilt-chin lift orjaw-thrust maneuver. If there is no spontaneous breathing, start artificial ventilation by pinching the nose closed with your thumb and index finger. Take a deep breath and seat your lips around the patient’s mouth (creating an airtight seal), and give two slow ventilations (1 1/2 to 2 seconds per breath). See figure 4-11. Allow enough time for the lungs to deflate between ventilations. If the patient still does not respond, continue mouth-to-mouth ventilations at the rate of 10 to 12 ventilations per minute or one breath every 5 seconds. Periodically, check the pupils for reaction to light; constriction is a sign of adequate oxygenation.

Figure 4-11.—Mouth-to-mouth ventilation.


When performing artificial ventilation and the lungs cannot be inflated adequately, repeat head tilt-chin lift or jaw-thrust maneuver, and again attempt ventilation. If the lungs still do not inflate adequately, assume the airway is obstructed by a foreign object.

MOUTH-TO-NOSE .—Mouth-to-nose ventilation is effective when the patient’s mouth cannot be opened (lockjaw), extensive facial or dental injuries occur, or an airtight seal of the mouth cannot be achieved. Figure 4-12 shows an example of this procedure.

Figure 4-12.—Mouth-to-nose ventilation.

To administer this technique, tilt the head back with one hand on the patient’s forehead and use the other hand to lift the jaw (as in the head tilt-chin lift maneuver). Close the victim’s mouth. Take a deep breath, seal your lips around the patient’s nose, and give two ventilations. Allow the victim’s lungs to deflate passively after each ventilation. If the victim does not respond, then you must fully inflate the lungs at the rate of 10 to 12 ventilations per minute or one breath every 5 seconds until the victim can breathe spontaneously.

MOUTH-TO-STOMA.—A casualty who has had surgery to remove part of the windpipe will breathe through an opening in the front of the neck called a stoma. Cover the casualty's mouth with your hand, take a deep breath, and seal your mouth over the stoma. Breathe slowly, using the procedures for mouth-to-mouth breathing. Do not tilt the head back. (In some situations, a person may breathe through the stoma as well as his nose and mouth. If the casualty’s chest does not rise, cover his mouth and nose, and continue breathing through the stoma.)

MOUTH-TO-MASK.—The mouth-to-mask breathing device includes a transparent mask with a one-way valve mouth piece. The one-way valve directs the rescuer’s breath into the patient’s airway while diverting the patient's exhaled air away from the rescuer. Some devices have an oxygen adaptor that permits the administration of supplemental oxygen.

Mouth-to-mask is a reliable form of ventilation since it allows the rescuer to use two hands to create a seal. Follow the steps below to perform the mouth-to-mask technique.

Step 1—Place the mask around the patient’s mouth and nose, using the bridge of the nose as a guide for correct position. Proper positioning of the mask is critical because gaps between the mask and the face will result in air leakage.

Step 2––Seal the mask by placing the heel and thumb of each hand along the border of the mask and compressing firmly to provide a tight seal around the margin of the mask.

Step 3––Place your remaining fingers along the bony margin of the jaw and lift the jaw while performing a head tilt.

Step 4––Give breaths in the same sequence and at the same rate as in mouth-to-mouth resuscitation; observe the chest for expansion.

Gastric Distention

Sometimes during artificial ventilation, air is forced into the stomach instead of into the lungs. The stomach becomes distended (bulges), indicating that the airway is blocked or partially blocked, or that ventilations are too forceful. This problem is more common in children but can occur with adults as well. A slight bulge is of little worry, but a major distention can cause two serious problems. First, it reduces lung volume: the distended stomach forces the diaphragm up. Second, there is a strong possibility of vomiting.

The best way to avoid gastric distention is to position the head and neck properly and/or limit the volume of ventilations delivered.


The American Red Cross (arc) states that no attempt should be made to force air from the stomach unless suction equipment is on hand for immediate use.

If suction equipment is ready and the patient has a marked distention, you can turn the patient on his side facing away from you. With the flat ofyour hand, apply gentle pressure between the navel and the rib cage. Be prepared to use suction should vomiting occur.


Cardiac arrest is the complete stoppage of heart function. If the patient is to live, action must be taken immediately to restore heart function. The symptoms of cardiac arrest include absence of carotid pulse, lack of heartbeat, dilated pupils, and absence of breathing.

A rescuer knowing how to administer cardiopulmonary resuscitation (CPR) greatly increases the chances of a victim’s survival. CPR consists of external heart compression and artificial ventilation. External heart compression is performed on the outside of the chest, and the lungs are ventilated by the mouth-to-mouth, mouth-to-nose, mouth-to­stoma, or mouth-to-mask techniques. To be effective, CPR must be started within 4 minutes of the onset of cardiac arrest. The victim should be supine on a firm surface.

CPR should not be attempted by a rescuer who has not been properly trained. If improperly done, CPR can cause serious damage. It must never be practiced on a healthy individual. For training purposes, use a training aid instead. To learn this technique, see your medical education department or an American Heart Association- or American Red Cross-certified Hospital medical technician, nurse, or physician.

One-Rescuer CPR

The rescuer must not assume that a cardiac arrest has occurred solely because the victim is lying on the floor and appears to be unconscious. First, try to rouse the victim by gently shaking the shoulders and trying to obtain a response (e.g., loudly ask: “Are you OK?”). If there is no response, place the victim supine on a firm surface. Always assume neck injuries in unconscious patients. Kneel at a right angle to the victim, and open the airway using the head tilt-chin lift or jaw-thrust methods described previously. Attempt to ventilate. If unsuccessful, reposition the head and again attempt to ventilate. If still unsuccessful, deliver five abdominal thrusts (Heimlich maneuver) or chest thrusts to open the airway. Repeat the thrust sequence until the obstruction is removed.

DETERMINING PULSELESSNESS.—Once the airway has been opened, check for the carotid pulse. The carotid artery is most easily found by locating the larynx at the front of the neck and then sliding two fingers down the side of the neck toward you (fig. 4-13). The carotid pulse is felt in the groove between the larynx and the sternocleidomastoid muscle. If the pulse is present, ventilate as necessary. If the pulse is absent, locate the sternum and begin chest compressions.

Figure 4-13.—Locating the carotid pulse.

PROPER POSITIONING OF HANDS ON STERNUM.—To locate the sternum, use the middle and index fingers of your lower hand to locate the lower margin ofthe victim’s rib cage on the side closest to you (fig. 4-14). Then move your fingers up along the edge of the rib cage to the notch where the ribs meet the sternum in the center of the lower chest. Place your middle finger on the notch and your index finger next to it. Place the heel of your other hand along the midline of the sternum next to your index finger. Remember to keep the heel of your hand off the xiphoid (tip of the sternum). A fracture in this area may damage the liver, causing hemorrhage and death.

Figure 4-14.—Proper position of hands on the sternum for chest compressions.

CHEST COMPRESSIONS.—Place the heel of one hand directly on the sternum and the heel of the other on top of the first. Interlock your fingers or extend them straight out and KEEP THEM OFF THE VICTIM’S CHEST! Effective compression is accomplished by locking your elbows into position, straightening your arms, and positioning your shoulders directly over hands so that the thrust for each chest compression is straight down on the sternum. See figure 4-15. The sternum should be depressed approximately 1 1/2 to 2 inches (for adults). Release chest compression pressure between each compression to allow blood to flow into the chest and heart. When releasing chest compression pressure, remember to keep your hands in place on the chest.

Figure 4-15.—Proper position of the rescuer.

Not only will you feel less fatigue if you use the proper technique, but a more effective compression will also result. Ineffective compression occurs when the elbows are not locked, the rescuer is not directly over the sternum, or the hands are improperly placed on the sternum.

PERFORMANCE AND REASSESSMENT OF CPR.—When one rescuer performs CPR, the ratio of compressions to ventilations is 15 to 2, and it is performed at a rate of 80 to 100 compressions per minute. Vocalize: “one and, two and, three and,...” until you reach 15. After 15 compressions, you must give the victim two slow ventilations (1 Y2 to 2 seconds). Continue for four full cycles. Quickly check for the carotid pulse and spontaneous breathing. If there are still no signs of recovery, continue CPR with compressions. Reassess the patient every few minutes thereafter.

If a periodic check reveals a return of pulse and respiration, discontinue CPR and place the victim in the recovery position. Continue monitoring the victim and be prepared to restart CPR.

Two-Rescuer CPR

If there are two people trained in CPR on the scene, one should perform chest compressions while the other performs ventilations. The compression rate for two-rescuer CPR is the same as it is for one-rescuer CPR: 80 to 100 compressions per minute. However, the compression-ventilation ratio is 5 to 1, with a pause for ventilation of 1 Y2 to 2 seconds consisting primarily of inspiration. Exhalation occurs during chest compressions.

Two-rescuer CPR should be performed with one rescuer positioned at the chest area and the other positioned beside the victim’s head. The rescuers should be on opposite sides of the victim to ease position changes when one rescuer gets tired. Changes should be made on cue without interrupting the rhythm.

The victim’s condition must be monitored to assess the effectiveness of the rescue effort. The person ventilating the patient assumes the responsibility for monitoring pulse and breathing. To assess the effectiveness of the partner’s chest compressions, the rescuer should check the pulse during compressions. To determine if the victim has resumed spontaneous breathing and circulation, chest compressions must be stopped for 5 seconds at the end of the first minute (20 cycles) and every few minutes thereafter.


Although it has fallen out to favor with some agencies, two-person CPR remains a viable method of resuscitation.

CPR for Children and Infants

CPR for children (1to 8 years old) is similar to that for adults. The primary differences are that the heel of only one hand is used to apply chest compressions, and ventilations are increased to a rate of 20 breaths per minute (once every 3 seconds). Chest compressions are performed on the lower half of the sternum (between the nipple line and the notch). The chest should be depressed approximately one-third to one-half (about 1 to 1 Y2 inches) the total depth of the chest.

For infants (under 1 year old), CPR is performed with the infant supine on a hard, flat surface. The hard surface may be the rescuer’s hand or arm, although using the arm to support the infant during CPR enables the rescuer to transport the infant more easily while continuing CPR. See figure 4-16. Once the infant is positioned on a hard surface, the airway should be opened using the head tilt-chin lift or jaw-thrust maneuver. Both maneuvers, however, must be performed very carefully and gently to prevent hyperextension of the infant’s neck. Pulselessness is determined by palpating the brachial artery (fig. 4-17). If the infant has no pulse and is not breathing, CPR must be started immediately.

Figure 4-16.—Infant supported on rescuer’s arm, and proper placement of fingers for chest compressions.

Figure 4-17.—Palpating brachial artery pulse in an infant.

To perform CPR on an infant, place your mouth over the infant’s nose and mouth, creating a seal. Give two slow breaths (1to 1 Y2 seconds per breath) to the infant, pausing after the first breath to take a breath. Pausing to take a breath after the first breath of each pair of breaths maximizes oxygen content and minimizes carbon dioxide concentration in the delivered breaths. Perform chest compressions by using two fingers to depress the middle of the sternum approximately 1/2 to 1 inch. See figures 4-16 and 4-18 for proper finger positioning for chest compressions.

Figure 4-18.—Locating proper finger position to perform chest compressions in infants.

For both infants and children, the compression rate should be at least 100 compressions per minute. Compressions must be coordinated with ventilations at a 5-to-1 ratio. The victim should be reassessed after 20 cycles of compressions and ventilations (approximately 1 minute) and every few minutes thereafter for any sign of resumption of spontaneous breathing and pulse. If the child or infant resumes effective breathing, place the victim in the recovery position.