Respiratory Rate
ABCs
definitions
- normal adult resting RR → 12–20 breaths/min
- tachypnea → > 20 · bradypnea → < 12
- RR ≥ 30 or < 8 → major red flag
- RR < 8 → severe bradypnea / hypoventilation, risk of respiratory arrest (absent effective breathing)
- confirm → recount manually for a full minute
- document pattern, depth, work of breathing, ability to speak, O₂ device/flow, SpO₂, mental state, hemodynamics
- if hypoxemic or O₂ requirement rising → follow oxygen desaturation pathway
HPI & examination
- onset, duration, trend, baseline RR, O₂ requirement
- by suspected cause
- dyspnea, cough, sputum, fever or pleuritic pain → infection / pulmonary disease
- wheeze or chest tightness → asthma / COPD
- sudden pleuritic pain, hemoptysis, syncope, immobility, leg swelling → PE
- sudden unilateral pain, reduced breath sounds → pneumothorax
- orthopnea, PND, edema, weight gain → pulmonary edema
- chest pain, diaphoresis, palpitations → ACS / arrhythmia
- diabetes, polyuria, vomiting, abdominal pain → DKA
- vomiting, diarrhea, renal disease, toxin exposure → metabolic acidosis
- pain, anxiety, fever, anemia, pregnancy, hyperthyroid symptoms
- opioids, sedatives, alcohol or other respiratory depressants
- head injury, stroke symptoms, seizures, raised ICP, neuromuscular weakness
- recent surgery, aspiration, procedures, trauma
- focused examination
- airway patency; respiratory effort, accessory muscles, paradoxical breathing, fatigue; ability to speak
- chest expansion, wheeze, crackles, unequal or absent air entry
- JVP, heart sounds, peripheral edema; perfusion and hemodynamics
- neurological state, pupils, neuromuscular weakness
- DVT, infection, metabolic dehydration signs
workup
organize by suspected physiology, not a fixed panel:
- oxygenation / ventilation → pulse oximetry, O₂ device/flow; ABG when accurate PaO₂/PaCO₂ needed; VBG can initially screen pH and CO₂ (cannot assess PaO₂)
- metabolic → glucose, ketones, bicarbonate, electrolytes, renal function, lactate when indicated
- infection / inflammation → CBC, CRP ± PCT, cultures, source-directed imaging when indicated
- cardiac → ECG, troponin, BNP, bedside echo when indicated
- PE → clinical probability first (Wells score · MDCalc ↗︎); D-dimer only if probability low to intermediate; CTPA if indicated
- anemia → CBC
- neurological / toxicological → glucose, medication/toxin review, directed imaging
calculator NEWS2 · MDCalc ↗︎ · supplements, does not replace, clinical assessment
management
A · hypoxemia / hypoxemic respiratory failure
- follow oxygen desaturation pathway; titrate O₂ to target using device appropriate to severity
- ABG when severe, worsening, or accurate PaO₂/PaCO₂ needed
- treat the cause: pneumonia, pulmonary edema, PE, pneumothorax, asthma / COPD, aspiration, mucus plugging, ARDS
- escalate support (conventional O₂ → HFNO → CPAP/NIV → intubation) by cause, work of breathing and gas exchange
- do not delay definitive treatment: tension pneumothorax, high-risk PE, other immediately reversible causes
B · hypercapnia / hypoventilation
- assess airway, respiratory effort, consciousness and ABG
- at risk of hypercapnic failure → controlled O₂ targeting 88–92% while gases assessed
- treat cause: bronchodilators + steroids for obstructive exacerbation, reverse respiratory depressants, secretion management, neuromuscular/obesity-hypoventilation/chest-wall management
- persistent acute hypercapnic acidosis after initial treatment → urgent respiratory / ICU review; NIV per cause-specific protocol (COPD threshold: persistent pH < 7.35 with PaCO₂ > 6.5 kPa after optimal therapy; verify against local protocol)
- reduced consciousness, inability to protect airway, severe exhaustion, NIV contraindication/failure, worsening acidosis → urgent ICU/anesthesia assessment for invasive ventilation
suspected opioid toxicity
- support oxygenation and ventilation first (bag-mask if needed), regardless of pathway below
- therapeutic / iatrogenic opioid respiratory depression (patient on prescribed opioids, not a suspected overdose)
- naloxone: 0.1 mg IV and titrate (opioid-dependent); 0.4 mg IV/IM if peri-arrest or severe depression (two-pathway detail)
- reassess RR and effort after 2–3 min; repeat in small increments
- goal: adequate ventilation, not complete arousal (especially opioid-dependent patients). Over-reversal risks severe pain, withdrawal, agitation, pulmonary edema
- recurrent depression → naloxone infusion at two-thirds of total effective bolus dose per hour; observe several hours beyond last dose, longer for long-acting agents (methadone, modified-release morphine, buprenorphine)
- severe overdose, apnea or life-threatening poisoning
- larger, repeated doses (e.g. 0.4–2 mg IV, repeated every 2–3 min) alongside immediate ventilatory support, per international guidance (AHA 2025 ECC)
- no response after appropriate repeated dosing → reconsider diagnosis
- either pathway → involve senior/toxicology/ICU early, especially for recurrent depression, unclear picture, or unexpected non-response
C · compensatory tachypnea from metabolic / systemic disease
- do not suppress compensatory hyperventilation
- treat underlying cause: DKA, sepsis, lactic acidosis, renal failure, salicylate toxicity, fever, pain, severe anemia
- DKA or severe metabolic acidosis → fluids, insulin / electrolytes or cause-specific treatment (hyperglycemia / DKA)
- if intubation considered in severe metabolic acidosis, call ICU/anesthesia early: failing to match high minute ventilation causes rapid deterioration
D · bradypnea
- assess airway; provide assisted ventilation if breathing inadequate
- look for opioids/sedatives, neurological injury, raised ICP, severe hypothyroidism, hypothermia, neuromuscular weakness
- reverse treatable toxins
- do not rely on oxygen alone when ventilation is failing
escalation
call senior / ICU / anesthesia urgently for
- RR ≥ 30 or < 8 (NEWS2 red flag) with any of the below, or a rapidly changing trajectory
- apnea, gasping or ineffective breathing
- inability to protect the airway
- severe work of breathing, exhaustion, deteriorating effort
- altered consciousness
- persistent / worsening hypoxemia or rising O₂ requirement
- acute hypercapnic respiratory acidosis
- hemodynamic instability
- need for HFNO, NIV, intubation, or support beyond ward capability
evidence
| source | type |
|---|---|
| RCP NEWS2 (Dec 2017, current) | international guideline |
| BTS/ICS acute hypercapnic respiratory failure guideline | international guideline |
| BTS emergency oxygen guidance | international guideline |
| NHS England Patient Safety Alert, inappropriate naloxone doses (2014) | international guideline |
| Kuwait MOH naloxone / opioid-reversal protocol | local-protocol verification required |
dosing follows international guidance (BNF, NHS England Patient Safety Alert 2014, AHA 2025 ECC). Verify naloxone preparation, route, and dosing against current Kuwait/MOH or hospital protocol.
Verify indication, dose, allergies, interactions, renal/hepatic function and local protocols before prescribing.
free the on-call checklist covers the whole shift on one printable page.
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Last clinically reviewed · 17 August 2026 · Last updated · September 2026