Respiratory emergencies

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Template:TOC-right In emergency medicine, ensuring the airway is not obstructed is usually the first priority in assessment and immediate measures. [1] The mnemonic "ABCD" gives the immediate priorities:

  • Airway: There must be a clear path from the nose or mouth to the lungs. Even if the patient is incapable of active breathing, air can be supplied externally, but if there is no way to oxygenate the blood, the brain will be irreparably damaged in 4-5 minutes at normal body temperature
  • Breathing: If the patient is making no respiratory effort, oxygen can be supplied externally, initially by mouth-to-mouth artificial respiration, manual bag-valve-mask device, or a mechanical ventilator. When the patient is breathing ineffficiently, supplemental oxygen may be adequate, or it may be necessary to paralyze the respiratory muscles and take over mechanical ventilation.
  • C:irculation. Blood needs to move, through regular or artificial heartbeat, or interventions to restore circulation.

Whenever there is even mild respiratory distress, emergency personnel must plan for contingencies; some conditions, such as anaphylactic shock can progress from itching and wheezing, to complete airway obstruction, in minutes.

If there is active respiratory distress or a strong index of suspicion that it is imminent, other supportive steps should be taken. A breathing patient should be put on oxygen. Establish at least two large-bore intravenous lines, draw several tubes of venous blood according to the local protocol, and attach the patient to a cardiac monitor-defibrillator. Attach a pulse oximeter, and, when available, a pulse capnometer. Take vital signs. Position the patient to assist respiration.

Immediate airway management

Without a patent airway, all other resuscitative efforts will be futile. The examiner begins by assessing the patient's level of consciousness and efficiency of breathing. If the patient is conscious, able to speak, not cyanotic, and has nonemergent vital signs and chest sounds, assessment can proceed to the evaluating urgent but not immediately life-threatening conditions. [2]

The following conditions justify immediate intubation:[3]

  1. No breathing at all (apnea)
  2. Glasgow Coma Scale < 9
  3. Sustained seizure activity.
  4. Unstable mid-face trauma.
  5. Airway injuries.
  6. Large flail segment or respiratory failure.
  7. High aspiration risk.
  8. Inability to otherwise maintain an airway or oxygenation.


Intubation

Preparation

  • Rapid sequence intubation

Nonsurgical airways

Invasive airways

Managing intubated patients in the ER

Other immediate threats to life

Upper airway obstruction

Neurologic impairments to respiration

Tension pneumothorax

Acute Respiratory Distress Syndrome

Severe aspiration into the respiratory tract

Severe pulmonary edema

Severe asthma

Asthma is, when acquired, usually a lifelong disease. The standard of treatment is to suppress the hyperimmune response, which, through the release of inflammatory factors, will lead to increasing difficulty. Criteria for an immediate asthmatic crisis include an inability to speak and intense perspiration. If the patient has difficulty in speaking and still has trouble breathing when in an optimal resting position, consider the exacerbation as severy. According to the diagnostic criteria of the U.S. National Asthma Education and Prevention Program.[4] Severe asthma has dyspnea at rest and can speak only with difficulty. The peak expiratory flow rate <40 percent predicted or personal best. The situation is Life threatening when respiratory distress makes it impossible to speak, the patient is perspiring, and the peak expiratory flow rate, if it can be taken, is <25 percent predicted or personal best.

Laryngospasm

Severe chronic obstructive pulmonary disease

Pulmonary fibrosis

Urgent threats to life

Chest wall defects

Lung collapse or mechanical problem

Insufficient lung parenchymal function

Airway disease

Pulmonary vascular disease

Neurogenic respiratory distress

Metabolically induced respiratory distress

Pleurisy

References

  1. The only intervention, assuming the patient is in a physically safe space, which will take priority is defibrillation for a witnessed cardiac arrest. Of course, if the patient is in a burning car or similar situation, extrication is an even higher priority.
  2. Boozer, Harriet L & Melissa M Cheeseman (2004), Chapter 8, Compromised Airway, in Stone, CK and Humphries R, Current Emergency Diagnosis & Treatment (5th ed.), Lange Medical Books/McGraw-Hill
  3. Editor, Trauma.org (November 24, 2006), Airway management of the Trauma Victim
  4. National Asthma Education and Prevention Program, Expert Panel Report III: Guidelines for the diagnosis and management of asthma, National Heart, Lung, and Blood Institute, 2007., NIH publication no. 08-4051