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Overview of Respiratory Arrest


Vanessa Moll

, MD, DESA, Emory University School of Medicine, Department of Anesthesiology, Division of Critical Care Medicine

Last full review/revision Apr 2020
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Interruption of pulmonary gas exchange for > 5 minutes may irreversibly damage vital organs, especially the brain. Cardiac arrest almost always follows unless respiratory function is rapidly restored. However, aggressive ventilation may also have negative hemodynamic consequences, particularly in the periarrest period and in other circumstances when cardiac output is low. In most cases, the ultimate goal is to restore adequate ventilation and oxygenation without further compromising a tentative cardiovascular situation.

Etiology of Respiratory Arrest

Respiratory arrest (and impaired respiration that can progress to respiratory arrest) can be caused by

  • Airway obstruction

  • Decreased respiratory effort

  • Respiratory muscle weakness

Airway obstruction

Obstruction may involve the

  • Upper airway

  • Lower airway

Upper airway obstruction may occur in infants < 3 months, who are usually nose breathers and thus may have upper airway obstruction secondary to nasal blockage. At all ages, loss of muscular tone with decreased consciousness may cause upper airway obstruction as the posterior portion of the tongue displaces into the oropharynx. Other causes of upper airway obstruction include blood, mucus, vomitus, or foreign body; spasm or edema of the vocal cords; and pharyngolaryngeal tracheal inflammation (eg, epiglottitis Epiglottitis Epiglottitis is a rapidly progressive bacterial infection of the epiglottis and surrounding tissues that may lead to sudden respiratory obstruction and death. Symptoms include severe sore throat... read more Epiglottitis , croup Croup Croup is acute inflammation of the upper and lower respiratory tracts most commonly caused by parainfluenza virus type 1 infection. It is characterized by a brassy, barking cough and inspiratory... read more Croup ), tumor, or trauma. Patients with congenital developmental disorders often have abnormal upper airways that are more easily obstructed.

Decreased respiratory effort

Decreased respiratory effort reflects central nervous system (CNS) impairment due to one of the following:

  • Central nervous system disorder

  • Adverse drug effect

  • Metabolic disorder

Central nervous system disorders that affect the brain stem (eg, stroke Overview of Stroke Strokes are a heterogeneous group of disorders involving sudden, focal interruption of cerebral blood flow that causes neurologic deficit. Strokes can be Ischemic (80%), typically resulting... read more Overview of Stroke , infection, tumor) can cause hypoventilation. Disorders that increase intracranial pressure usually cause hyperventilation initially, but hypoventilation may develop if the brain stem is compressed.

Drugs that decrease respiratory effort include opioids and sedative-hypnotics (eg, barbiturates, alcohol; less commonly, benzodiazepines). Combinations of these drugs further increase the risk of respiratory depression (1 Etiology references Respiratory arrest and cardiac arrest are distinct, but inevitably if untreated, one leads to the other. (See also Respiratory Failure, Dyspnea, and Hypoxia.) Interruption of pulmonary gas exchange... read more ). Usually, an overdose (iatrogenic, intentional, or unintentional) is involved, although a lower dose may decrease effort in patients who are more sensitive to the effects of these drugs (eg, older patients, deconditioned patients, patients with chronic respiratory insufficiency or obstructive sleep apnea). The risk for opioid-induced respiratory depression (ORID) is most common in the immediate postoperative recovery period but persists throughout a hospital stay and beyond. OIRD can lead to catastrophic outcomes such as severe brain damage or death. (2 Etiology references Respiratory arrest and cardiac arrest are distinct, but inevitably if untreated, one leads to the other. (See also Respiratory Failure, Dyspnea, and Hypoxia.) Interruption of pulmonary gas exchange... read more )

In December 2019, the US Food and Drug Administration (FDA) issued a warning that gabapentinoids (gabapentin, pregabalin) may cause serious breathing difficulties in patients using opioids and other drugs that depress the CNS, those who have underlying respiratory impairment such as patients with chronic obstructive pulmonary disease Chronic Obstructive Pulmonary Disease (COPD) Chronic obstructive pulmonary disease (COPD) is airflow limitation caused by an inflammatory response to inhaled toxins, often cigarette smoke. Alpha-1 antitrypsin deficiency and various occupational... read more Chronic Obstructive Pulmonary Disease (COPD) (COPD), or older patients.

CNS depression due to severe hypoglycemia or hypotension ultimately compromises respiratory effort.

Respiratory muscle weakness

Weakness may be caused by

  • Neuromuscular disorders

  • Fatigue

Respiratory muscle fatigue can occur if patients breathe for extended periods at a minute ventilation exceeding about 70% of their maximum voluntary ventilation (eg, because of severe metabolic acidosis Metabolic Acidosis Metabolic acidosis is primary reduction in bicarbonate (HCO3−), typically with compensatory reduction in carbon dioxide partial pressure (Pco2); pH may be markedly low or slightly subnormal... read more or hypoxemia).

Etiology references

  • 1. Izrailtyan I, Qiu J, Overdyk FJ, et al: Risk factors for cardiopulmonary and respiratory arrest in medical and surgical hospital patients on opioid analgesics and sedatives. PLoS One Mar 22;13(3):e019455, 2018. doi: 10.1371/journal.pone.0194553

  • 2. Lee LA, Caplan RA, Stephens LS, et al: Postoperative opioid-induced respiratory depression: A closed claims analysis. Anesthesiology 122: 659–665, 2015. doi: 10.1097/ALN.0000000000000564

Symptoms and Signs

With respiratory arrest, patients are unconscious or about to become so.

Patients with hypoxemia may be cyanotic, but cyanosis can be masked by anemia or by carbon monoxide or cyanide intoxication. Patients being treated with high-flow oxygen may not be hypoxemic and therefore may not exhibit cyanosis or desaturation until after respiration ceases for several minutes. Conversely, patients with chronic lung disease and polycythemia may exhibit cyanosis without respiratory arrest. If respiratory arrest remains uncorrected, cardiac arrest follows within minutes of onset of hypoxemia, hypercarbia, or both.

Impending respiratory arrest

Before complete respiratory arrest, patients with intact neurologic function may be agitated, confused, and struggling to breathe. Tachycardia and diaphoresis are present; there may be intercostal or sternoclavicular retractions. Patients with CNS impairment or respiratory muscle weakness have feeble, gasping, or irregular respirations and paradoxical breathing movements. Patients with a foreign body in the airway may choke and point to their necks, exhibit inspiratory stridor, or neither. Monitoring end-tidal carbon dioxide can alert practitioners to impending respiratory arrest in decompensating patients.

Infants, especially if < 3 months, may develop acute apnea without warning, secondary to overwhelming infection, metabolic disorders, or respiratory fatigue.

Patients with asthma Asthma Asthma is a disease of diffuse airway inflammation caused by a variety of triggering stimuli resulting in partially or completely reversible bronchoconstriction. Symptoms and signs include dyspnea... read more or with other chronic lung diseases may become hypercarbic and fatigued after prolonged periods of respiratory distress and suddenly become obtunded and apneic with little warning, despite adequate oxygen saturation.

Diagnosis of Respiratory Arrest

  • Clinical evaluation

Respiratory arrest is usually clinically obvious; treatment begins simultaneously with diagnosis. The first consideration is to exclude a foreign body obstructing the airway; if a foreign body is present, resistance to ventilation is marked during mouth-to-mask or bag-valve-mask ventilation Bag-Valve-Mask Devices If no spontaneous respiration occurs after airway opening and no respiratory devices are available, rescue breathing (mouth-to-mask or mouth-to-barrier device) is started; mouth-to-mouth ventilation... read more . Foreign material may be discovered during laryngoscopy for endotracheal intubation (for removal, see Clearing and Opening the Upper Airway Clearing and Opening the Upper Airway Airway management consists of Clearing the upper airway Maintaining an open air passage with a mechanical device Sometimes assisting respirations (See also Overview of Respiratory Arrest.) read more ).

Treatment of Respiratory Arrest

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