Respiratory Rate in Prehospital Care

Respiratory rate is one of the fundamental vital signs and serves as a critical indicator of a patient’s respiratory and overall physiological status. Despite its importance, it is often under-assessed or inaccurately measured in pre-hospital settings.

This article highlights the significance of accurately assessing respiratory rate, provides guidance on proper measurement techniques, and discusses the clinical implications of abnormal respiratory rates.

Assessing Respiratory Rate

Accurate assessment begins with observing the patient’s breathing without making them aware of your focus. Awareness can cause the patient to alter their breathing pattern, leading to inaccurate measurements.

Discreet Observation: While still palpating the radial pulse—but no longer counting it—begin assessing the patient’s respiratory rate. Continuing to hold the patient’s wrist serves to distract them from the fact that you are observing their breathing.

Visual Cues: Watch the rise and fall of the patient’s chest or abdomen. Each full cycle of rise and fall counts as one breath.

Note Breathing Phases: Pay attention to any asymmetries between the expiratory and inspiratory phases. For instance, a prolonged expiratory phase is common in asthma exacerbations and patients with Chronic Obstructive Pulmonary Disease (COPD).

Additional Observations: Look for use of accessory muscles, nasal flaring, or pursed-lip breathing, which may indicate respiratory distress.

Calculating Respiratory Rate

To ensure the most accurate measurement:

Count for 60 Seconds: Assess the patient’s respiratory rate over a full minute to calculate the number of breaths per minute. While some practitioners count for 30 seconds and multiply by two, a full 60-second count reduces the margin of error, especially in patients with irregular breathing patterns.

Consistency: Perform the measurement when the patient is at rest, if possible, to avoid activity-induced variations.

Normal Respiratory Rates

In healthy adults, the normal respiratory rate ranges between 12-20 breaths per minute. It’s essential to recognize that factors like stress, fever, or physical activity can temporarily influence this rate.

Normal respiratory rates vary significantly with age:

Infants (<1 year): 30-60 breaths per minute

Toddlers (1-3 years): 24-40 breaths per minute

Pre-schoolers (4-5 years): 22-34 breaths per minute

School-age Children (6-12 years): 18-30 breaths per minute

Adolescents (13-18 years): 12-20 breaths per minute

Note: Children have higher metabolic rates and oxygen demands, making them more susceptible to rapid respiratory compromise.

Respiratory Rate Abnormalities

Understanding deviations from the normal range is crucial for early intervention.

Definition: A respiratory rate of more than 20 breaths per minute.

Possible Causes: Acute asthma attacks, pneumonia, pulmonary embolism, anxiety, pain, fever, or metabolic acidosis.

Clinical Significance: Tachypnoea is often a compensatory mechanism for hypoxia or hypercapnia and may precede more severe respiratory compromise.

Definition: A respiratory rate fewer than 12 breaths per minute.

Possible Causes: Opiate overdose, head injury, increased intracranial pressure, or severe hypoxia.

Clinical Significance: Bradypnoea can lead to hypoventilation, resulting in elevated carbon dioxide levels and respiratory acidosis.

Key Points

Bibliography

American Heart Association (2020). CPR & ECC Guidelines. cpr.heart.org. Available at: https://cpr.heart.org/en/resuscitation-science/cpr-and-ecc-guidelines

Joint Royal Colleges Ambulance Liaison Committee, & Association of Ambulance Chief Executives. (2022). JRCALC Clinical Guidelines 2022. Class Professional Publishing

National Institute for Health and Care Excellence (2007). Overview | Acutely ill adults in hospital: recognising and responding to deterioration | Guidance | NICE. Nice.org.uk. Available at: https://www.nice.org.uk/guidance/cg50

Resuscitation Council UK (2021). 2021 Resuscitation Guidelines. Resuscitation Council UK. Available at: https://www.resus.org.uk/library/2021-resuscitation-guidelines