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The clinical course and subsequent deterioration due to choking progress rapidly. In ideal circumstances, bystanders should resolve the airway obstruction, because even the promptest EMS agencies will not arrive in time to perform needed interventions.

Patients presenting with complete airway obstruction should receive abdominal thrusts or the Heimlich maneuver [11, 14, 15]. In the classic Heimlich procedure, the rescuer positions him or herself behind the sitting or standing patient, placing his or her arms around the chest at the level of the epigastrium. The rescuer places one fist against the epigastrium, using the other hand to apply quick upwards thrusts. The rescuer repeats the process until the obstruction clears [15]. Studies of a circumferential “horizontal” abdominal thrust with the same hand placement as the Heimlich, but with straight backward thrust, has shown similar airway pressures as for the Heimlich. Since this approach is below the ribcage, there is less likelihood to damage the internal organs or ribs [16].

For the unconscious patient, current Advanced Cardiac Life Support (ACLS) guidelines recommend performing standard CPR chest compressions [10]. The only caveat is that before giving breaths, rescuers should look inside the mouth to visualize and remove any foreign bodies. Abdominal compressions and blind finger sweeps are no longer recommended for unconscious persons [10, 11].

For infants less than 1 year of age, the rescuer typically positions the victim with the head downward, alternating back blows with chest compressions. Bulb suction, visualized finger sweeps, and back blows often work well without the need for chest compressions [10, 11, 17].

EMS personnel responding to a choking emergency must be prepared to manage the advanced stages of crisis and must act quickly on arriving at the scene. Bystanders may have failed to recognize that the patient is choking, leading emergency medical dispatchers to miscategorize the call as a condition other than choking (e.g., respiratory distress, chest pain, or unconscious person) due to inaccurate or incomplete information from the 9‐1‐1 caller. Bystanders may have already made unsuccessful attempts to clear the obstruction with the Heimlich maneuver. The patient may be unconscious or in cardiac arrest.

On confirming the presence of complete airway obstruction, rescuers should perform the Heimlich maneuver or chest compressions [10, 11, 18]. In cases of partial airway obstruction, rescuers should monitor for signs of cyanosis, inadequate breathing, or unconsciousness, signifying the need to immediately provide the Heimlich maneuver or chest compressions. If the Heimlich maneuver does not resolve the obstruction, ALS personnel may attempt to directly visualize the airway with a laryngoscope, making efforts to remove visualized foreign bodies using Magill forceps [19]. A table maneuver where the choking person is laid prone over a table, head and arms hanging over the side, and then receives sharp back blows from the rescuer between the scapula, has been successful in case studies [20]. Using a head down, inverted approach allows gravity to help expel the foreign body as seen in children, provided it can be done safely and without injuring the rescuer or victim [21]. Foreign bodies below the vocal cords may be more problematic. Anecdotal reports suggest using a rigid suction catheter in these situations. A cadaver study and case studies are promising for a portable, nonpowered, suction generating device called the LifeVac® that provides pressures far greater than any of the aforementioned techniques [22]. Although data in this area are lacking, intubation is risky in these cases and may further lodge the foreign body. As a last resort, rescuers may consider performing cricothyroidotomy or transtracheal jet ventilation. This approach will only work if the surgical airway is placed below the foreign body. There are anecdotal reports of using high‐pressure jet ventilation to eject entrapped foreign bodies. However, there are no organized reports of choking management using cricothyroidotomy or jet ventilation.

For patients with partial airway obstructions, there are additional management options. The patient should be encouraged to cough and expel the object. High‐flow supplemental oxygen may be appropriate, although the sensation of the mask may make the patient feel uncomfortable, aggravating the situation. If the patient is able to adequately move air, it may be acceptable, and even preferable, to carefully transport the patient to the hospital for definitive care. In these cases, close monitoring of vital signs, oxygen saturation, respiratory effort, and level of consciousness are essential.

Monitoring end‐tidal carbon dioxide may also help to reveal early clinical deterioration, though research data on this are lacking. EMS personnel should provide advanced notification to the receiving facility so that the emergency department can prepare its equipment and summon appropriate personnel. Because this is an airway emergency, it typically makes the most sense to go to the nearest hospital. At the receiving hospital, the patient may require urgent sedation, direct or video laryngoscopy, or surgical airway intervention by an emergency physician, otolaryngologist, anesthesiologist, or surgeon. Many emergency departments have a “difficult airway” algorithm that involves summoning various specialists to provide assistance in these emergency airway situations.

Many postchoking victims refuse EMS care and/or transport. In general, however, it is recommended that patients who have their choking resolved before EMS arrival, or by EMS clinicians, be transported to the hospital for further evaluation to ensure that no complications have occurred [10, 13, 15]. This recommendation is based primarily on case reports of laryngospasm, pulmonary edema, anoxic brain injury, and retained foreign body occurring after choking episodes. In addition, there are case reports of damaged internal organs following abdominal and chest thrusts [23]. A patient who persists in refusing transport should be made aware of these possible risks.

As a final consideration, an anaphylactic reaction may masquerade as an upper airway obstruction, especially if the patient has recently eaten nuts [24]. If the history and presentation are suggestive of this situation, EMS clinicians should consider therapy with epinephrine and antihistamines.