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Chapter 30: Glossary

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Chapter 30: Glossary

Abdominal thrusts: The procedure used to help clear an upper airway obstruction in a choking individual who is awake but unable to make sounds.  

ABG: See arterial blood gas

Acid-Base Balance: Refers to the balance of acid and alkaline compounds.  Measured on the pH scale, an increase in acids causes a decrease in pH; an increase in alkaline compounds causes an increase in pH.  The lungs and kidneys are the primary organs that work to establish acid-base balance.  See Respiratory acidosis, Metabolic acidosis, Respiratory acidosis, and Respiratory alkalosis.

Acrocyanosis: A bluish or purplish discoloration of the hands, feet, and distal parts of the face caused by disruptions in circulation. This condition is usually caused by decreased oxygenation to the tissues.

ACS: See Acute Coronary Syndrome

Acute Coronary Syndrome: This syndrome refers to diseases that can reduce coronary blood flow and ultimately can lead to cardiac ischemia or infarction.  Typically, classified as either STEMI or NSTE-ACS.

Acute Life-Threatening Events Recognition and Treatment Program: Program designed by a facility to ensure the early identification and treatment of pre-arrest patients as well as identify if a patient is deteriorating even after interventions are performed.  The program often includes involving the family and patient to alert staff of changes in the condition of the patient.

Acute Respiratory Distress Syndrome: This disorder occurs when fluid builds up in the alveoli causing the lungs not to receive enough air. In most cases, this is often caused by sepsis, inhalation of substances, and severe pneumonia.  With the decreased oxygen, less oxygen moves into the blood and, therefore, less oxygen is available on the cellular level.  The most common symptom is severe shortness of breath with rapid respiratory rate and hypotension.

Adenosine: Medication used as a second-line treatment for supraventricular tachycardia when vagal maneuvers have not stopped the arrhythmia.  Side effects include shortness of breath and hypotension.  Not useful for atrial fibrillation and flutter or ventricular tachycardia.  Side effects may include chest pain, skin flushing, ventricular ectopy, and bradycardia.  The dose is an initial rapid push of 6 mg followed by a normal saline bolus.  A 12 mg dose can be given 1 to 2 minutes after an ineffective initial dose.

Adjunctive therapies: Additional therapies used in ACLS that helps to stabilize the patient to reduce long-term mortality.

AED: See Automated external defibrillator

Afterload: The pressure which the heart must use to eject blood during systole.  This measurement is influenced by the aortic pressure of the left ventricle and pulmonary artery pressure of the right ventricle.  When afterload increases, the cardiac output decreases.

Agonal gasps: Also called agonal respirations, it is an abnormal respiratory pattern characterized by gasping or struggling to breathe due to a decrease in the oxygen circulating in the blood.

Airway obstruction: A partial or complete blockage of any of the breathing passages that lead to the lungs.  Airway obstruction is usually classified as upper or lower obstruction and can be caused by mechanical or disease-specific causes.

ALERT Program: See Acute Life-Threatening Events Recognition and Treatment Program

Algorithm: The set of sequential steps prescribed to treat a specific condition.

Alternative airway: An adjunct that is often used to ensure that the patient is adequately ventilated.  The alternative airways usually used include the endotracheal tube or laryngeal mask.

Amiodarone: Medication used to control arrhythmias, including ventricular tachycardia and fibrillation, supraventricular tachycardia, wide complex tachycardia, and atrial fibrillation.  Common side effects include hypotension, toxicity, visual changes, pneumonitis, and gastrointestinal symptoms.  The initial dose is 300 mg with a second dose of 150 mg if needed.

Analgesia: Refers to the loss of pain sensation from a deliberate disruption of the neural pathways between the sensory organ and the brain.  

Apnea: A temporary cessation of breathing that results in no movement of air into or out of the lungs.  

ARDS: See Acute Respiratory Distress Syndrome

Arrhythmia: A medical condition in which the heart beats in an abnormal rhythm.  In the infant, PEA and bradycardia are the most common arrhythmias.

Arterial blood gas: Measurement of pH, pCO2, pO2, and HCO3 in an arterial blood sample.  Normal values in the adult population are: pH = 7.35-7.45; pCO2 =27-41mmHg; pO2 = 80-100mmHg; and HCO3 = 19-27 mmol/L.

Assessment, Primary: Includes an assessment of Airway-Breathing-Circulation-Disability-Exposure approach (ABCDE) to evaluate the respiratory function, cardiac function, and neurologic function of the patient. This also includes taking the patient’s vital signs.

Assessment, Secondary: Includes a history of the present illness and a focused physical assessment based on the patient’s current condition.

Asystole: Also called cardiac standstill or flatline.  In this state, the heart has stopped beating, and the patient has no cardiac output or heart muscle activity.

Atrial fibrillation: Abnormal heart rhythm caused by the irregular beating of the atria out of coordination with the ventricles.

Atrial flutter: An electrocardiogram rhythm used to describe various sorts of atrial tachycardia.  This condition may often display as a second-degree heart block as the atrial rate becomes very rapid.  This rhythm can be treated with medication, cardiac pacing, or cardioversion.  In rare recurrent cases, ablation therapy or surgical procedures might be necessary.

Atrioventricular (AV) node: Part of the electrical system of the heart, the AV node coordinates the electrical conduction between the right atrium and right ventricle. The AV node is activated by impulses from the SA node.

Atrioventricular block: Also called AV block, this condition is an impairment of electrical impulses from the cardiac atria to the ventricles in the heart.  This is usually caused by a block at the atrioventricular junction. Further classified as a first, second, or third degree.

Atropine: Drug of choice for the treatment of symptomatic bradycardia.  May be useful for AV block but will not be useful for Mobitz Type II block, PEA, or asystole.  The provider should be prudent in cases of hypoxia and MI since atropine significantly increases oxygen demand.  Usually given in a dose of 0.5 mg every 3 to 5 minutes.  Doses less than 0.5 mg may cause slowing of the heart.

ATV: see Automatic Transport Ventilator

Automated external defibrillator: A portable device that evaluates the heart rhythm and delivers an appropriate electrical shock to the heart when a shockable rhythm is detected.

Automatic Transport Ventilator: ATVs are small, lightweight ventilators that can be used in an out-of-hospital respiratory or cardiac arrest to support ventilations until the patient can be transported to the hospital.  Depending on the model, the ATV may have the capability of providing CPAP or BiPAP.  Advantages over manual ventilation include control of rate and volume, reduction of the chance of hyperventilation, ability to titrate oxygen more closely to prevent hyper- or hypo-oxygenation, audible warning of possible airway obstruction, and freeing a rescuer to perform other tasks.  Limitations include: operator education on the machine, oxygen must be available in sufficient quantities, and the ability to “feel” lung compliance is not available.

Autonomy: An ethical concept that preserves the patient’s right to make choices about their treatment, including the right to refuse treatment.

AV Block: See atrioventricular block.

AVPU response scale: A system used to evaluate an individual’s responsiveness quickly.  The mnemonic stands for: Alert (fully awake and alert), Voice (responds to voice commands), Pain (responds only to pain), Unresponsive (does not respond to voice or pain).

Bag-Valve Mask Ventilation: A BVM is a hand-held device that requires a rescuer to provide breaths to patients who have inadequate or absent breathing.  Any healthcare provider should be trained to use this essential part of the resuscitation standard equipment.  The BVM can be used without additional oxygen, but if higher oxygen concentrations are required, supplemental oxygen must be available.

Barrier device: A device between the patient and rescuer that is used for rescue breathing. This device protects both individuals from the transfer of microorganisms.

Basic Life Support: The most basic level of medical care that can be used by field personnel or trained bystanders to support the injured or ill patient until definitive treatment can be delivered at a hospital.

Beneficence: The ethical concept that implies that caregivers will do what is in the best interest of the patient.

Biphasic defibrillator: The biphasic defibrillator is the standard in most Emergency departments. These defibrillators can be adjusted to increase or decrease the current and is more efficient at lower power than the older monophasic defibrillator. The biphasic defibrillator delivers a shock from two vectors. By delivering a lower power, there is less chance for damage to the heart muscle.

BLS: See Basic Life Support

Bradycardia: An abnormally slow heart rate for the individual’s age.  In the adult population, the normal heart rate is 60 to 100 beats per minute. The heart rate normally varies with activity.  

Bradypnea: A lower than normal respiratory rate (usually less than 12 to 18 breaths per minute for an adult).

BVM: See bag-valve-mask ventilation

C-A-B Sequence: The current and preferred CPR sequence that teaches Chest Compressions, Airway management, and breathing.  The rationale for this order is that the individual cannot survive without circulation, but can survive for a short time without additional oxygen entering the circulation.

Calcium channel blockers: Also called calcium antagonists since these medications block calcium from entering cells. They relax arterial walls and are often used to lower blood pressure.

Calcium: The most abundant mineral in the body, calcium is required for cardiac contraction and vasodilation.  Typically, calcium levels are held relatively constant in the body as the body can readily pull calcium from the bones.

Capillary refill time: The time it takes for color to return to a capillary bed after pressure is applied.  In newborns and younger children, the pressure is often applied to the sternum for several seconds.  Normal capillary refill time in the neonate is 3 seconds; in adults and older children, the normal time is less than 2 seconds.

Carbon dioxide detector: A device used to detect the amount of carbon dioxide to prevent excessive levels of carbon dioxide in systemic circulation.

Carbon dioxide: Often represented as CO2, carbon dioxide is a colorless gas that is a by-product of respiration that occurs during normal expiration.

Cardiac Arrest: The sudden cessation of heart function.  In the pediatric population, a cardiac arrest is rarely a primary event; instead, it is usually the result of deteriorating respiratory function leading to respiratory failure and ultimately to cardiac arrest.  This condition is often called cardiopulmonary arrest or failure.

Cardiac markers: Biomarkers that measure the function of the heart. They are used to diagnose cardiac disease and MI.

Cardiac output: The volume of blood pumped by the ventricle each minute.  Normally, this is calculated as heart rate X stroke volume. The pediatric population has a higher normal cardiac output than adults, usually as a result of the higher normal heart rate.

Cardiac tamponade: A serious but rare condition in which the heart is compressed due to fluid accumulation in the pericardial sac around the heart.  The cause is usually chest trauma.  Symptoms include restlessness, decreased level of consciousness, tachypnea, and sharp chest pain.  Treatment will include pericardial tap and management of blood pressure.

Cardiopulmonary resuscitation, high quality: High quality CPR refers to the current American Heart Association recommendations of a compression rate of 100 to 120 per minute for all ages and a compression depth of at least two inches for adults and a depth of at least one-third of the anterior-posterior diameter of the chest for infants and children (usually 1.5 to 2 inches).

Carina: On the trachea, the point at which the two mainstem bronchi branch out.

Central cyanosis: Bluish or purplish discoloration of the lips and mucous membranes.  Although it can be caused by certain congenital deformities, it is most often the result of decreased oxygen in the blood.

Chain of Survival: According to the AHA ACLS standards, the Chain of Survival include those steps that must be done to increase the chance for positive outcomes in a cardiac arrest situation.  The steps include: Calling for trained emergency care, Early and high-quality CPR, Early application of shock therapy (defibrillation) as appropriate, and Early ACLS as appropriate.  Inability to perform any of these steps may result in increased morbidity and mortality in an arrest situation.

CHF: See Congestive heart failure

Cincinnati Prehospital Stroke Scale: An easy-to-use assessment that can be used by laypersons and medical personnel.  In this scale, the person doing the assessment looks at the patient’s facial droop, arm drift, and clearness of speech.  Abnormal findings on any of these parameters are suggestive of stroke requiring immediate intervention.  

Closed-loop communication: A communication technique that involves the sender sending a message which is repeated back by the individual receiving the message.  If the message is correct, the original sender responds with a “yes” message.  

Compression fraction: Defined as the portion of CPR time during which compressions are actually being performed during cardiopulmonary resuscitation.  To improve survival rates, the rescuer should strive for a compression fraction of 60 to 80%.

Compression-only CPR:  Lay rescuers who are not trained in full CPR or who feel uncomfortable with the process are encouraged to learn compressions-only CPR to maintain sufficient circulation until definitive assistance arrives.  If an AED is readily available, the lone rescuer should use the AED before beginning CPR.

Compression-ventilation ratio: Refers to the number of chest compressions and breaths during cardiopulmonary resuscitation.  For single-rescuer situations, the ratio is 30 compressions for 2 ventilations for all ages.  When two rescuers are available, the compression-ventilation ratio remains at 30 to 2 for adults but changes to 15 compressions to two ventilations for the pediatric population.

Congestive heart failure: Characterized by severe shortness of breath, irregular heartbeat, and fatigue, CHF is a common heart disease often caused by coronary artery disease that leads to damage to muscles of the heart.  

Contiguous leads: On a 12-lead ECG, the leads that look at the same anatomical areas of the heart. The term is also used to describe precordial leads that are next to each other. Used to diagnose the area of injury in the heart. Inferior leads are II, III, and aVF; Lateral leads are I, aVL, V5, and V6; Septal leads are V1 and V2; Anterior leads are V3 and V4. 

Continuous positive airway pressure (CPAP): A form of ventilation that applies continuous air pressure throughout the respiratory cycle to keep airways open.  Typically used in individuals who can breathe on their own.

Continuous Quality Improvement: The focus of CQI is to improve outcomes by improving: the education of the community, CPR quality, rapid response systems, and post-cardiac arrest care.  In this process, the team sets goals, develops processes to meet the goals, measures progress, and holds individuals accountable.

Coronary angiography: Used in cardiac catheterization, the coronary angiogram is a specialized x-ray with a radioactive agent that highlights occlusion of arteries of the heart. 

Coronary arteries: The blood vessels that supply blood to the myocardium.  The two large coronary arteries are the left main and the right coronary arteries.  The left main further divides into the left anterior descending artery that supplies blood to the left ventricle and atrium and the circumflex artery that circles the heart and supplies blood to the outside and back of the heart.  

Coronary atherosclerosis: Narrowing of a cardiac artery usually due to buildup of plaque.

Coronary thrombosis: Formation of a blood clot in one of the vessels of the heart. 

CPAP: See continuous positive airway pressure.

CPR, High Quality: See Cardiopulmonary resuscitation

CQI: See Continuous Quality Improvement

Cricoid pressure: No longer routinely recommended in ACLS, in this maneuver, a provider applies pressure on the cricoid cartilage of the neck to occlude the esophagus and make the glottis more visible.

Cricothyrotomy: An emergency procedure to establish an airway when a patent airway cannot be established by positioning or placement of an airway.  Typically, the cricothyrotomy is only performed when the airway is obstructed or when a facial injury prevents the provider from establishing an airway.

Cyanosis: A bluish or purplish discoloration of the skin due to decreased oxygen in the blood.  See acrocyanosis and central cyanosis.

Debriefing, cold: Documentation of the resuscitation at a later time after the resuscitation efforts.  This is typically done in a face-to-face meeting after the team has had an opportunity to process the events of the resuscitation.  The goal of a cold debriefing is to capture the effective and ineffective parts of the effort to improve care for all patients for continuous quality improvement.

Debriefing, hot: A meeting immediately following resuscitation efforts when the team has the best memory of events that occurred during the resuscitation.  The goal of a hot debriefing is to capture the effective and ineffective parts of the effort to improve care for all patients for continuous quality improvement.

Defibrillation: The definitive treatment for ventricular tachycardia or fibrillation that consists of delivering an unsynchronized shock to the cardiac muscle using a defibrillator.

Depolarization: In the normal heart, the SA node begins the electrical activity by sending a signal through the atria, causing those chambers to contract (P wave on the ECG). When the impulse reaches the AV node, the ventricles contract (QRS on the ECG).

Dopamine: A vasopressor commonly indicated for the treatment of cardiogenic or distributive shock.  Dopamine will increase the patient’s SVR, heart rate, and contractility of the heart. Given as an infusion at a titrated rage between 2 and 20 micrograms per kg body weight per minute.  Hypovolemia should be corrected before administration.

DOPE: Mnemonic to be used to remind the team of possible causes of respiratory deterioration after intubation (Displaced ETT, Obstructed ETT, Pneumothorax, Equipment failure).

Early Warning Sign Systems: A system defined by the facility that includes signs and symptoms that should result in specific interventions by the care team. Signs and symptoms include respiratory rate, oxygen saturation decrease, use of supplemental oxygen, elevated or decreased temperature, low or high systolic blood pressure, increased or decreased heart rate, and altered level of consciousness.

E-C technique: A one-handed technique for holding a face mask on the patient during ventilation.  In this technique, the thumb and index finger form a C over the top and bottom of the mask and the other three fingers for an E by holding the individual’s mandible.  Unless the rescuer has large hands, this technique is less effective in adults than in children.

ECG: See electrocardiogram.

Echocardiogram: Non-invasive ultrasound test that evaluates the heart muscle and valves.

Edema: The abnormal collection of fluid in soft tissues resulting in swelling.  In adults, usually appears in the lower extremities.  In the fetus, edema in fetal compartments (abdominal, pleural, or pericardial) is a serious condition that can be fatal to the developing fetus.

Ejection fraction: Measurement of the amount of blood being pumped by the heart with each contraction.  EF is typically expressed as a percentage with normal being between 55 and 70%.  Lower EF measurements may be indicative of heart failure.

Electrocardiogram (ECG): A non-invasive recording of the electrical activity of the heart.  Electrodes are placed in specific locations on the individual’s skin to record activity in all areas of the heart.

Endotracheal intubation: Also called tracheal intubation; the placement of a plastic tube into the trachea to keep the individual’s airway open and provide a means for administering epinephrine during resuscitation.  In the infant, endotracheal intubation is always done through the mouth.  

End-tidal Carbon Dioxide: Used to determine the adequacy of CPR, end-tidal CO2  is a non-invasive measurement of exhaled carbon dioxide through a capnograph. If the measurement is less than 10 mm Hg, blood flow to the lungs is decreased, and the team should assume that compressions or airway management are not optimal.

Epiglottis: An elastic cartilage shaped like a flap that overlies the glottis.

Epinephrine: A naturally occurring hormone that aids in the regulation of the sympathetic autonomic nervous system.  As a powerful vasopressor, epinephrine (or adrenaline) increases blood pressure, heart rate, and cardiac output.  In resuscitation, epinephrine is used as a cardiac stimulant to treat persistent bradycardia, cardiac arrest rhythms, anaphylaxis, and hypotension.  In cardiac arrest, the dose is 1mg every 3 to 5 minutes of a 1:10000 solution.  This may be followed by an infusion at a rate of 0.1 to 0.5 mcg per kg per minute.  

ET tube: A plastic tube that is used in the endotracheal intubation procedure to keep the airway patent.

EWSS: See Early Warning Signs Symptoms

Exclusion criteria: Those findings that would alert a provider that a patient is not a good candidate for treatment. May be absolute (should never be done) or relative (the provider should use clinical judgment when making the treatment decision).

Extracorporeal Cardiopulmonary Resuscitation: Known by different names (ECLS and ECMO), this is a type of mechanical circulatory support for patients with cardiogenic shock that is not responsive to medical treatment.  These technologies provide temporary support for cardiac output and oxygenation until definitive treatment is established.

FBAO: Foreign body airway obstruction.  See Airway obstruction.

Fibrinolytic checklist: The steps the team should go through to determine a patient’s suitability for fibrinolytic treatment.

Fibrinolytic Therapy: Use of fibrinolytic agents such as recombinant tissue plasminogen activator (rTPA) to dissolve clots in coronary vessels.  

Fibrinolytics: Medications used to dissolve clots by attacking the fibrin in the clot.

First degree AV block: A cardiac dysrhythmia caused by an obstruction in the heart’s conduction system at the AV node. The impulse through the AV node is slowed, causing a prolonged PR interval on the ECG.

Flow-inflating bag: One of the two types of manual ventilation bag; the flow-inflating bag requires a constant flow of air into the bag.  This bag is a good choice for neonates since the provider can maintain fine control of tidal volume.  Also, see self-inflating bag.

Foreign body obstruction: Obstruction of the upper airway due to aspiration of food or small objects.  Particularly in the pediatric population, this type of obstruction should be considered when there is inspiratory stridor, tachypnea, or increased inspiratory effort.

FRC: See functional residual capacity.

Functional residual capacity (FRC): Refers to the amount of air left in the lungs at the end of passive expiration.  During passive expiration, the lungs and chest wall are in equilibrium, and there is no pressure on the respiratory muscles.  The air remaining in the lungs makes it easier to fill the lungs with the next inspiration.  If inhalation and exhalation are not in balance, the patient will have a decreased ability to absorb oxygen or remove carbon dioxide.

Gasping: Abnormal respiratory effort in which the individual attempts to inhale or exhale with quick ineffective breaths.  The clinician should immediately intervene to provide effective ventilation.

GCS: See Glasgow Coma Scale

Glasgow Coma Scale: Method for evaluating the level of consciousness to determine the severity of head injury using eye-opening, best verbal response, and best motor response.  Mild = 13-15; Moderate = 9-12; Severe = 3-8.  The team must understand the modifications necessary for evaluating the child and infant.

Glottis: An opening of the larynx, a passageway into the trachea.

Glucose:  Amount of sugar in the blood.  Normal glucose in the adult is 80 to 120 mg per dL of blood before meals.  At bedtime, the normal level is 100 to 140 mg per dL.

H’s and T’s: The most common causes of cardiac arrest including hypovolemia, hypoxia, hydrogen ion excess, hypo/hyperkalemia, hypothermia, tension pneumothorax, tamponade, toxins, and thrombosis (pulmonary or coronary).  Correction of these disorders will often resolve the cardiac arrest situation.

Head-tilt chin-lift maneuver: Technique for opening the airway in which the patient’s head is tilted and chin is lifted, so the head is in the “sniffing” position.  This technique should NOT be used if there is a suspected cervical spine injury.  Instead, in this population, the team should use the jaw-thrust maneuver.

Hemorrhagic stroke: Brain infarction caused by rupture of a blood vessel with bleeding into the brain.

Heparin: Medication used for its anticoagulant effects. 

Hypercapnia: Abnormally high carbon dioxide level in the blood.  This is caused by the retention of carbon dioxide.  The body’s normal mechanism for this condition is to increase the respiratory rate.

Hypercarbia: Greater than normal carbon dioxide levels in the blood resulting in respiratory alkalosis.  Usually caused by hypoventilation.

Hyperglycemia: Above the normal level of sugar in the blood.  Normal glucose in the adult is 80 to 120 mg per dL of blood before meals.  At bedtime, the normal level is 100 to 140 mg per dL.

Hyperkalemia: Higher than normal potassium level.  Normal potassium level is between 3.5 and 5.5 millimoles per liter.  Hyperkalemia is a normal variation in extremely premature infants. Variations in the adult population are associated with increased morbidity and mortality.

Hypertension: Hypertension is defined as blood pressure higher than normal expected.  In 2017, the American Heart Association and American College of Cardiology redefined the guidelines for blood pressure.  In the new guidelines, the following categories apply:

Category Definition
Normal < 120/80 mm Hg
Elevated Systolic BP 130-139 AND diastolic BP <80 mm Hg
Stage 1 Systolic BP 130-139 OR diastolic BP 80-89 mm Hg
Stage 2 Systolic >139 OR diastolic at least 90 mm Hg
Hypertensive Crisis Systolic >180 OR diastolic >120 mm Hg

Hyperthermia: A higher than normal temperature. Normal adult temperature is 97.0 to 99.0 degrees Fahrenheit (36.1 to 37.2 degrees Centigrade).

Hypocapnia: Less than normal carbon dioxide levels in the blood resulting in respiratory alkalosis.  Usually caused by hyperventilation, it can lead to tetany, dizziness, and confusion.

Hypoglycemia: A lower than normal blood glucose level.  Normal glucose in the adult is 80 to 120 mg per dL of blood before meals.  At bedtime, the normal level is 100 to 140 mg per dL.

Hypokalemia: Lower than normal potassium level.  Normal potassium level is between 3.5 and 5.5 millimoles per liter.  Hyperkalemia is a normal variation in extremely premature infants. Variations in the adult population are associated with increased morbidity and mortality.

Hypotension: A lower than normal blood pressure.  

Hypothermia: A lower than normal temperature.  Normal adult temperature is 97.0 to 99.0 degrees Fahrenheit (36.1 to 37.2 degrees Centigrade).

Hypovolemia: A lower than normal blood volume.  Normal adult blood volume is approximately 9% of total body weight.  In the average adult, this is approximately 3.5 to 5.0 liters.

Hypovolemic shock: Significant blood or body fluid loss resulting in a sudden drop in blood volume that can lead to the inability for the heart to pump enough oxygen to the vital organs.

Hypoxemia, permissive: Refers to the concept of allowing lower than normal oxygen levels in arterial blood to prevent the risks of high oxygen therapy.  

Hypoxemia: Abnormally low level of oxygen in arterial blood most often caused by respiratory disorders or obstruction.

Hypoxia: Inadequate oxygen supply at the tissue level to meet the metabolic demands of the individual.  Causes of hypoxia can include pulmonary disease, congenital heart disease, airway obstruction, or sepsis.  Hypoxia will often lead to hyperventilation.  

IHCA: See In-hospital Cardiac Arrest

In-hospital Cardiac Arrest: A cardiac arrest that occurs within the confines of an acute care hospital.  Improved outcomes are associated with in-hospital arrest, but, more importantly, with post-arrest care that occurs in the hospital setting.

Inspiratory time: The time for inhalation.  In a ventilated individual, it is the amount of time to deliver the tidal volume to the lung.  

Intraosseous (IO) access: Circulatory access through the bone marrow when the umbilical vein or other IV access is not readily available.  In the case of cardiac arrest, IO access is a quick and easy way to establish circulatory access.  Contraindicated if there is a long-bone fracture in the extremity.  

Intravenous (IV) access: Circulatory access through a vein.  During CPR, this is the route of choice if a site can be obtained without interrupting compressions.  Due to the size of veins in a neonate, this route is less commonly used than IO or umbilical vein access.

Invasive arterial blood pressure: IBP monitoring measures the arterial blood pressure by inserting an arterial line into an accessible artery.

IO: See intraosseous access.

Ischemic changes: On the ECG, changes (usually in the ST-segment and T-wave) that indicate that myocardial damage (ischemia) has occurred. This usually involves ST deviation from the isoelectric line and changes in the T wave.

Ischemic stroke: Brain infarction caused by occlusion of a blood vessel that supplies the brain resulting in decreased oxygen to the cells and cellular death.

IV: See intravenous access.

Jaw-thrust maneuver: Technique for opening the airway of a patient when a cervical spine injury is possible.  The provider pushes the lower jaw forward while maintaining the neck in a neutral position.  

Lactic acidosis: A type of metabolic acidosis, lactic acidosis can be caused by hypoglycemia, hypoxia, seizures, kidney disease, certain poisonings, and prolonged dehydration.  Any of these disorders can cause the blood pH to be lower than normal.

Laryngeal mask: A supraglottal airway that keeps the individual’s airway open.  Easier to insert than an endotracheal tube, the laryngeal mask helps to ensure an airtight seal on top of the glottis.

Laryngoscope: A type of endoscope used to visualize the larynx.  The laryngoscope is typically a rigid instrument equipped with a light that illuminates the vocal cords.

Larynx: An anatomical segment that connects the pharynx and the trachea.

LEAN (meds for ET tube): Those medications that can be safely administered via an ET tube. The meds are lidocaine, epinephrine, atropine, and Narcan.

Lidocaine: Antiarrhythmic medication indicated for ventricular fibrillation or pulseless ventricular tachycardia, wide-complex tachycardia with pulses, and in rapid sequence intubation.  Lidocaine decreases the automaticity of the cardiac fibers and decreases intracranial pressure.  In cardiac arrest, the initial dose is 1 to 1.5 mg/kg body weight, followed by a dose of 0.5 to 0.75 mg per kg for refractory ventricular fibrillation.  This should be followed by an infusion of 1 to 4 mg per minute.

Lower airway obstruction: Refers to the obstruction of the bronchi and bronchioles in the chest cavity.  

Magnesium sulfate: Bronchodilator and electrolyte replacement indicated for refractory asthma, Torsades de pointes, and low magnesium levels.  Relaxes smooth muscle and acts as antiarrhythmic.  Not recommended for cardiac arrest due to VF or pulseless VT.  In cases where it is indicated, the dose is 1 to 2 grams diluted in 10 mL of D5W.

Main bronchi: Major air passageway leading to the right and left lungs.

Manual defibrillator: A defibrillator that requires medical decision-making and rhythm analysis by the provider to deliver a shock. An automated defibrillator interprets the rhythm and recommends a shock when appropriate.

Mechanical capture: When non-invasive, transcutaneous pacing is implemented, mechanical capture is the contraction of the heart that results in a pulse and increased cardiac output.

Metabolic acidosis: When the kidneys cannot remove acids, body fluids become acidosis.  In the pediatric population, the most common type is diabetic ketoacidosis.  Severe and long-lasting diarrhea can cause too much sodium bicarbonate to be lost.  Finally, lactic acidosis can be caused by hypoglycemia, hypoxia, seizures, kidney disease, certain poisonings, and prolonged dehydration.  

Metabolic alkalosis: When the blood has high levels of bicarbonate, and the kidneys cannot excrete the excess, the blood pH increases.  This is typically due to decreased oxygenation, fever, lung disease, and high altitude.  Symptoms include muscle spasms and tremor, nausea and vomiting, tingling, and confusion. 

Monomorphic Ventricular Tachycardia: Ventricular tachycardia in which the heart beats originate from the same source and the QRS complexes look similar on the ECG.

Monophasic defibrillator: The monophasic defibrillator is the older style of a defibrillator that has been replaced by the biphasic in most EDs. These defibrillators deliver a shock in a single direction from one chest electrode to the other. Higher energy levels must be used with a monophasic defibrillator which can result in heart damage.

Myocardial oxygen demand: The amount of oxygen the heart needs to function optimally. The demand is related to the level of activity of the heart.

Myocarditis: Inflammation of the middle layer (myocardium) of the heart.  A viral infection is the most common cause of myocarditis.

Myocardium: The thick, middle layer of the heart wall that contains primarily contractile muscle cells.

Naloxone: Also called Narcan, this medication can be given to reverse respiratory depression caused by opioid overdose.  Most emergency responders (police, fire, EMS) now carry naloxone.  A lay rescuer who has been trained can also give naloxone to reverse an opioid overdose.

Nasopharyngeal airway: Airway adjunct used in the management of less severe cases of airway obstruction. The NPA is inserted through the nose and to the base of the tongue to prevent the tongue from covering the epiglottis.

Nasopharynx: The upper part of the throat behind the nose and above the soft palate.  

National Institutes of Health Stroke Scale (NIHSS): A tool used to quantify the level of impairment caused by a stroke at a particular point in time.

Nitrates: Vasodilators that increase the diameter of blood vessels, causing decreased work of the heart and decreased blood pressure.

Nitroglycerin: A specific nitrate used to decrease pain and blood pressure in AMI.

Non-shockable rhythms: Cardiac arrhythmias that will NOT respond to cardioversion or defibrillation.  The two rhythms include PEA and asystole.  They are considered non-shockable since they do not have an electrically identifiable spike.

Non-ST-segment myocardial infarction: One of the forms of acute coronary syndrome, the NSTE-ACS symptoms include those associated with unstable angina.  NSTE-ACS is differentiated from STEMI by analysis of the ST-segment on the ECG.  For the NSTE-ACS, the ST-segment is normal.  Typically, damage due to this type of MI is less than for the STEMI.

Norepinephrine: A vasopressor indicated for the treatment of hypotensive shock that is not responsive to fluid resuscitation.  The usual dosage is 0.1 to 0.5 mcg per kg body weight per minute.

Normal Sinus rhythm: The cardiac rhythm that results when the electrical impulse originates in the sinus node and travels through the normal conduction pathway to produce the rhythm that is characteristic of a healthy heart at rest.

Normothermia: A normal temperature.  For the newborn, the normal range is 97.7 to 99.5 degrees Fahrenheit (36.5 to 37.5 degrees Centigrade).

NPA: See nasopharyngeal airway.

NSTE-ACS: see Non-ST-segment myocardial infarction

OHCA: See Out-of-hospital Cardiac Arrest

Opioid toxicity: Overdose due to excessive opioids resulting in decreased respirations and loss of consciousness.

Oropharyngeal airway: An airway adjunct used to maintain an open airway by preventing the tongue from falling back over the epiglottis and causing airway obstruction.

Orthostatic intolerance: Low blood pressure and dizziness when standing. The symptoms usually subside when the individual lies down.

Out-of-hospital Cardiac Arrest: A cardiac arrest that occurs in any location other than an acute care hospital.  Differences in the availability of treatment modalities make the survival of an OHCA more unlikely than survival from an IHCA.  It is estimated that there are approximately 35,000 OHCA events each year.

Oxygen blender: A device that mixes oxygen with compressed air.  This device allows the clinician to deliver less than 100% oxygen but greater than room air (21%) oxygen.

Oxygen saturation: The percentage of oxygen-rich hemoglobin relative to the total hemoglobin.  At the time of birth, all infants will have an oxygen saturation of less than 70%.  Within the first 10 minutes, the normal neonate’s oxygen saturation should be 85 to 95%. Normal for a child and adult will be >94% when breathing room air.

Oxygen: The chemical element that is often specified as O2.  Room air contains approximately 21% oxygen at sea level.  Recommendations are to begin resuscitation at room air and then titrate based on pulse oximetry.

Paroxysmal supraventricular tachycardia (PSVT): A type of supraventricular tachycardia that usually begins and ends abruptly. May causes shortness of breath, palpitations, and lightheadedness.

PCI: See Percutaneous Coronary Intervention

PEA: See pulseless electrical activity.

Peak Expiratory Flow Rate: Measures the patient’s maximum speed of expiration.  PEFR is measured using a peak flow meter.  This measurement is most reliable in adolescents and adults who understand the measurement process and is less useful in young children.  The normal PEFR is based on gender, age, and height.

Peak inspiratory pressure (PIP): The highest pressure in the lungs during the inspiratory phase.  Studies have shown that infants who require a high peak inspiratory pressure during mechanical ventilation are more likely to die of respiratory causes.

PEEP: See Positive end-expiratory pressure.

PEFR: see Peak Expiratory Flow Rate

Percutaneous Coronary Intervention: Along with fibrinolytics, one of the most commonly used interventions to treat STEMI.  In this procedure, stents are placed in the occluded cardiac vessel to hold the vessel open mechanically. As compared with fibrinolytic therapy, studies show that PCI has better long-term results for keeping vessels open with less risk of stroke and death.

Perfusion pressure: The difference between the diastolic pressure in the aorta and the left ventricular end-diastolic pressure.

Pericardiocentesis: Aspiration of fluid from around the heart.

Peripheral cyanosis: Blue or purple discoloration of the hands and feet.  Normal in the neonate, this is a sign of decreased oxygenation in the older individual.

PETCO2: See End-tidal Carbon Dioxide

PIP: See peak inspiratory pressure.

Pneumothorax: A condition in which a lung is partially or completely collapsed.  A common cause of a pneumothorax is trauma to the chest.  Another common cause in all age groups is over-inflation of the lungs from aggressive ventilation that causes the alveoli to rupture.

Polymorphic Ventricular Tachycardia: Ventricular tachycardia in which the heart beats originate from different sources and the QRS complexes look different on the ECG.

Positive End-expiratory pressure (PEEP): A form of ventilation that applies air pressure at the end of exhalation in the respiratory cycle to keep airways from collapsing during rest.  

Positive pressure ventilation (PPV): Technique of artificial respiration using a mechanical ventilator to force air into the lungs of the patient.  PPV is used when spontaneous breathing is either inadequate or absent.  The first ventilator was a negative pressure model known as the iron lung.  Cumbersome and limiting, the negative pressure ventilator is rarely used.  PPV is administered through a tube to expand the lungs.  When the ventilator breath stops, passive recoil of the chest occurs causing exhalation. PPV is accomplished by volume cycled ventilators (those that terminate the inspiration at a preset volume), pressure cycled ventilators (those that terminate the inspiration at a preset pressure), or time cycled ventilators (those that terminate the inspiration at a preset time).  

Post-cardiac arrest Care: Measures used to reduce morbidity and mortality after successful resuscitation.  Most important during the period following ROSC is: maintaining adequate blood pressure, running serial EKGs, therapeutic hypothermia, and monitoring the oxygenation using waveform capnography as indicated.

PPV: See Positive pressure ventilation.

Precordial thump: A procedure that can be used in V-Fib or pVT in a witnessed arrest in which a defibrillator is not available. The caregiver strikes the patient in the middle of the sternum with a closed fist.

Preload: Refers to the end-diastolic volume that increases the volume of the ventricles before contraction of the ventricles.

Priority-based multiple-rescuer response: The protocol that designates who on a team performs what functions and in what order.  A resuscitation often begins with one rescuer, and other team members join the team as they are available.  Facility protocol will designate what the essential duties are and who will accomplish each task in the context of the team.

Procainamide: An antiarrhythmic that works as a sodium channel blocker.

PSAP: See Public Safety Answering Points.

Public Safety Answering Points: A community-based protocol that trains EMS dispatchers to do “just in time” training to members of the public who might discover a patient in cardiac arrest.

Pulmonary edema: Accumulation of fluid in the air spaces in the lungs that results in impaired exchange and eventually respiratory failure.

Pulmonary embolism: Mechanical blockage of a blood vessel in the lungs leading to chest pain, cough, and shortness of breath.  A PE can result in obstructive shock leading to low cardiac output, decreased tissue perfusion, and an increase in systemic vascular resistance to compensate for the other issues.

Pulse oximetry: The measurement of oxygen through the skin.  Pulse oximetry should always be available and utilized when resuscitation is anticipated or when supplementary oxygen or PPV is administered after birth.  Studies show that there is no benefit to resuscitation with high oxygen concentrations (> 65%) as compared to low concentrations (21-30%).

Pulseless electrical activity (PEA): A common arrhythmia during resuscitation in which the cardiac monitor shows electrical activity without palpable pulses.  In this situation, defibrillation is not the treatment of choice.  Instead, the team must continue CPR and quickly identify the cause of the arrest from the Hs and Ts.  The most common cause of PEA is hypoxemia.

Pulseless ventricular tachycardia: Life-threatening cardiac arrhythmia characterized by a rate greater than 180 beats per minute, wide QRS complex, lack of palpable pulse, and the rhythm originates in the ventricles rather than the atrial node.

pVT: See Pulseless ventricular tachycardia

Quantitative Waveform Capnography: Non-invasive and continuous measurement of end-tidal carbon dioxide.  This is the best way to verify ventilation in the intubated patient during cardiopulmonary resuscitation.  It is the most reliable method for detecting the return of spontaneous circulation.

Rapid Response Team: An RRT is a way to proactively predict and intervene when a patient in the hospital is deteriorating.  In the best scenario, the family and visitors are trained to recognize small changes in the patient’s condition or mentation that might indicate that his condition is worsening.  When the RRT is summoned, the team can intervene quickly and forestall a full deterioration that might result in full cardiopulmonary arrest.

Recombinant Tissue Plasminogen Activator: rTPA is a laboratory-produced tissue plasminogen activator used to treat ischemic stroke.  

Recovery position: Following the return of effective circulation and breathing, the rescuer should roll the patient onto his side with the head in a dependent position.  This position will help to maintain a patent airway by decreasing pressure on the patient’s lungs and allowing emesis to flow out of his mouth.

Refractory: In the heart, the time when the muscle cannot contract. It is the time immediately following a contraction.

Reperfusion therapy: Any treatment that restores blood flow. This may include removal of a blockage or dissolving a clot in an occluded artery.

Repolarization: In the normal heart, the successive relaxation of the atria and ventricles following the contraction of the chambers. T-wave on the ECG.

Respiratory acidosis: When the lungs cannot remove carbon dioxide, body fluids become acidic resulting in respiratory acidosis.  This disorder is most often caused by chest injuries or chronic lung or airway disease. Symptoms include shortness of breath and confusion.

Respiratory alkalosis: When the blood has low levels of carbon dioxide, the blood pH increases.  This is typically due to decreased oxygenation, fever, lung disease, and high altitude.  Symptoms include muscle spasms and tremor, nausea and vomiting, tingling, and confusion. 

Respiratory arrest: Absent or extremely inadequate oxygenation and ventilation.  This condition assumes that the patient has a palpable pulse and circulation.

Respiratory distress: In infants, the primary cause is a lack of development of the lungs and lack of surfactant. Without surfactant, the alveoli of the lungs deflate and are increasingly hard to inflate.  Although uncommon in term infants after 39 weeks gestation, respiratory distress in this population commonly is due to congenital abnormalities, very rapid labor, or problems during delivery that reduce blood flow to the infant.  In older children and adults, airway obstruction is often the cause of this disorder.

Respiratory failure: Occurs when the gas exchange between the air and the blood cannot match the metabolic demands of the body.  Signs and symptoms of impending respiratory failure include bradypnea or tachypnea, tachycardia or bradycardia, hypertension, stridor, diminished breath sounds, paradoxical chest wall movement, wheezing, and use of accessory muscles during respiration. Respiratory failure is the most common cause of morbidity and mortality in the pediatric population.

Return of Spontaneous Circulation: Refers to the return of cardiac and significant respiratory effort after a cardiac arrest event.  Signs of ROSC include palpable pulses, spontaneous movement, respiratory effort, and blood pressure that can be measured.

ROSC: See Return of Spontaneous Circulation

RRT: See Rapid Response Teams

rTPA: See Recombinant Tissue Plasminogen Activator

SAMPLE: A mnemonic used during resuscitation to remind the team of further questions to consider before, during, and after resuscitation.  The mnemonic stands for Signs/Symptoms, Allergies, Medications, Past medical history, Last meal, and Events leading up to the precipitating event.

Second degree AV block (Type 1 and Type 2): A cardiac dysrhythmia caused by an obstruction in the heart’s conduction system at the AV node. In Type 1, the impulse through the AV node is progressively increased, resulting in increasingly long PR intervals until a QRS is completely missing on the ECG. In Type 2, you will see more than one P wave for every conducted QRS complex. 

Self-inflating bag: One of the two types of manual ventilation bag; the self-inflating bag refills itself when the provider stops squeezing the bag.  Also, see a flow-inflating bag.

Shock, Hypovolemic: Low volume shock usually caused by fluid loss from nausea, vomiting, infections, or electrolyte imbalance.  As fluids decrease in the body, the heart must work harder and beat faster to maintain cardiac output.

Shock: A life-threatening medical condition characterized by rapid breathing, cool skin, rapid and weak pulse, dizziness, faintness, and, ultimately, decreased blood pressure.  Categorized as compensated or decompensated.  Also typed as anaphylactic, cardiogenic, distributive, hemorrhagic, hypovolemic, and septic.

Shockable rhythms: An arrhythmia that can be interrupted by electrical shock.  The two rhythms are VF and pulseless VT.

Sinoatrial (SA) node: Sometimes called the heart’s pacemaker, the SA node is the small group of cells in the right atrium that produces an electrical impulse through the heart that causes it to contract.

Sinus tachycardia: A rhythm that originates in the atria but has a faster than expected heart rate for the individual’s age.

SOC: See Systems of Care

Sodium bicarbonate: An electrolyte that acts as an alkalinizing agent.  Although less commonly used in resuscitation than in the past, sodium bicarbonate continues to be indicated for very severe metabolic acidosis, certain poisonings, and hyperkalemia.

Sotalol: An antiarrhythmic that is another option for the treatment of arrhythmias.

ST-Elevation Myocardial Infarction: Often called STEMI, this heart attack is characterized by cardiac muscle damage due to a decreased blood supply to a part of the heart.  This MI is seen as ST-segment elevation on the ECG. Also, see N-STEMI.

STEMI: see ST-Elevation Myocardial Infarction

Stridor: An abnormal breath sound that is usually described as high-pitched or crowing. It is often associated with airway obstruction.

Stroke volume: Refers to the volume of blood pumped out of the left ventricle with each contraction.  

Stroke: Typically classified as hemorrhagic (bleeding into the brain) or ischemic (blocked artery), a stroke is often referred to as a “brain attack” since blood flow to a part of the brain is diminished or absent causing deprivation of oxygen to that part of the brain.  Symptoms may include weakness or paralysis, difficulty speaking or understanding speech, and confusion.

Suction equipment: Including the catheter and machine, suction equipment is used to clear the airway of secretions.  Initial suctioning of the newborn might be done by a bulb syringe.  

Supraglottic airway devices: Adjunct airway devices such as a laryngeal mask that are used to manage the patient’s airway during cardiac arrest.

Supraventricular tachycardia: A fast heart rhythm that originates above the ventricles.  Signs and symptoms of SVT include chest pain, diaphoresis, shortness of breath, and dizziness.

SVT: See Supraventricular tachycardia

Synchronized cardioversion: Delivery of low energy shock that is timed to be delivered at a particular point in the QRS complex when the rhythm is in the refractory period, and the arrhythmia is most likely to be interrupted.  The purpose is to restore normal cardiac activity and to convert atrial fibrillation, atrial flutter, atrial tachycardia, and supraventricular tachycardia when medications have not been successful.

Systems of Care: The AHA guidelines stress the importance of the development of total systems of care with training for all levels from community members, emergency response systems, physicians, and hospitals.

Tachycardia, Stable: Abnormally high heart rate.  In the adult population, the normal heart rate is 60 to 100 beats per minute. The heart rate normally varies with activity.  A faster than normal heart rate can be caused by infection, illness, fever, and medications.  Stable tachycardia is characterized by no significant signs or symptoms.  The team must support the patient while attempting to identify the underlying cause of the tachycardia.

Tachycardia, unstable:  Abnormally high heart rate.  In the adult population, the normal heart rate is 60 to 100 beats per minute. The heart rate normally varies with activity.  A faster than normal heart rate can be caused by infection, illness, fever, and medications.  Unstable tachycardia is characterized by a lower than normal cardiac output that causes serious signs and symptoms.

Tachypnea: Abnormally high respiratory rate (typically greater than 12 to 18 breaths per minute for an adult).  Tachypnea is a sign of impending respiratory failure in all age groups, so should be monitored and treated.

Targeted Temperature Management: See Therapeutic hypothermia

Therapeutic hypothermia: Lowering the core temperature using cooling devices.  Typically used after cardiac arrest to shunt blood from the periphery to the vital organs (brain, heart, and lungs).  The temperature is usually lowered to 89-93 degrees Fahrenheit (32-34 degrees Centigrade) and maintained for 24 hours or less.

Third-degree AV block: A cardiac dysrhythmia caused by an obstruction in the heart’s conduction system that causes an impulse not to move into the ventricle. At this point, an accessory pacemaker in the ventricle will begin to generate the QRS complexes. On the ECG, the P waves will usually be regular but will not be associated with the QRS complexes.

Thoracentesis: A procedure in which a catheter is inserted into the pleural space as a method of removing air or fluid inside the thoracic cavity.

Thyroid cartilage: A thick cartilage surrounding the larynx to protect it.

Torsades de Pointes: A heart arrhythmia that is often described as a polymorphic ventricular tachycardia.  The danger of this arrhythmia is that it can degenerate into ventricular tachycardia or ventricular fibrillation that can result in sudden cardiac death.

Toxins: Poisons that may be produced by the body or introduced from an external source.

Trachea: The segment of the airway between the larynx and the carina.

Transthoracic pacing: The regulation of the heart rate by an artificial pacemaker whose electrodes are attached to the external chest wall.

Troponin: One of the biomarkers that measure proteins that are released when the cardiac muscle is damaged. An elevated troponin may be an indicator of AMI.

Upper airway obstruction: Refers to a blockage of the trachea, larynx, or throat that impairs air movement into the lungs.  

Vagal maneuvers: Refers to techniques to slow supraventricular tachycardic rhythms.  Bearing down as if having a bowel movement, carotid massage, and immersing the face in ice water are common vagal maneuvers that may slow rapid rhythms.

Valsalva maneuver: Refers to the technique of exhaling forcefully against a closed nose and mouth.  This technique may be successful in slowing a tachycardic cardiac rhythm.

Vascular resistance: Refers to the resistance of blood flow through vessels in the circulatory system.  When in the peripheral circulation, this resistance is known as systemic vascular resistance (SVR).  In the lungs, it is termed pulmonary vascular resistance (PVR).

Vasopressin: An alternative to epinephrine for refractory ventricular fibrillation not relieved by shock.  May also be used for asystole, PEA and septic shock.  The clinician should be aware of the potential for angina, so should be avoided in patients with coronary artery disease.  The dose is 40 units to replace the first or second dose of epinephrine.  Can be followed by an infusion of 0.02 to 0.04 units per minute.

Ventilation-perfusion mismatch: The ventilation-perfusion ratio assesses the adequacy of the respiratory process.  When there is a mismatch, it is an indication that either the lungs are receiving oxygen with no blood flow or blood flow with no oxygen.

Ventricular Fibrillation: A cardiac arrhythmia that is characterized by fibrillation of the ventricles of the heart instead of effective contractions.  In the pediatric population, this arrhythmia is uncommon and occurs mostly in the context of preexisting cardiomyopathy.

Verapamil: A calcium channel blocker used to treat hypertension, anginal chest pain, and supraventricular tachycardia.

VF: See Ventricular Fibrillation

Vocal cords: Made up of two membranous tissues at opposite locations that project medially from the walls of the larynx, they form a slit across the glottis. The edges of the vocal folds vibrate when an airstream passes through causing modulation to produce the voice.

Wide complex tachycardia: A special type of tachycardia in which the QRS complex is greater than 120 ms due to slow ventricular depolarization.

Wolff-Parkinson-White syndrome: A supraventricular tachycardia resulting from an unusual electrical conduction pathway (bundle of Kent) between the atria and ventricles. The ECG will show a shortened PR interval and a characteristic delta wave with a tachycardic heart rate.

Work of breathing: Refers to the energy required to inhale and exhale.  The calculation is typically measured as Joules/Liter or Joules/minute.  In a normal resting individual, approximately 3% of total energy is consumed during the process of breathing.  The calculation is the work of breathing = Pressure X Volume.  If either of these factors increases, the work of breathing also increases.