What to give a patient in respiratory distress or requiring sedation?

Management of Respiratory Distress and Sedation in Acute Care

For patients in respiratory distress or requiring sedation, midazolam is the first-line sedative medication, with oxygen therapy titrated to maintain SpO2 of 88-92% in patients at risk of hypercapnic respiratory failure or 94-98% in other patients. 1

Oxygen Therapy Management

Initial Approach

• For patients in respiratory distress, oxygen therapy should be titrated to achieve target oxygen saturations of 94-98% in most patients and 88-92% in those at risk of hypercapnic respiratory failure 1
• Oxygen should be entrained as close to the patient as possible to minimize leakage and optimize delivery 1
• Continuous monitoring of oxygen saturation via pulse oximetry is essential prior to, during, and after any procedure involving sedation 1

Advanced Respiratory Support

• High-flow nasal oxygen (HFNO) and non-invasive ventilation (NIV) should be used only in selected patients with hypoxemic respiratory failure 1
• NIV should be considered if the patient has mild respiratory distress, but should be used with airborne precautions due to potential for aerosolization 1
• If respiratory distress and/or hypoxemia cannot be alleviated after standard oxygen therapy, consider HFNO or NIV with close monitoring 1
• If conditions do not improve or worsen within 1-2 hours of NIV, tracheal intubation and invasive mechanical ventilation should be implemented promptly 1

Sedation Management

Midazolam Administration

• Midazolam is a potent short-acting benzodiazepine that is often prescribed for sedation in respiratory distress 1, 2
• For adult sedation/anxiolysis during procedures:
  • Initial dose: 0.5 to 2 mg IV (titrated to effect)
  • Total dose: Usually does not exceed 5 mg 2
• For continuous IV infusion in critical care settings:
  • Loading dose: 0.05 to 0.2 mg/kg administered over at least 2-3 minutes
  • Maintenance: 0.06 to 0.12 mg/kg/hr (1 to 2 mcg/kg/min) 2

Important Precautions with Sedation

• Midazolam is 3-4 times more potent per mg than diazepam; slow administration and individualization of dosage is essential 2
• Continuous monitoring of respiratory and cardiac function (pulse oximetry) is required for all patients receiving midazolam 2
• Titration to effect with multiple small doses is essential; allow 3-5 minutes between doses to assess peak CNS effect 2
• Immediate availability of resuscitative drugs and equipment is mandatory 2

Sedation in Patients with NIV

• In agitated/distressed patients on NIV, intravenous morphine 2.5-5 mg (± benzodiazepine) may provide symptom relief and improve NIV tolerance 1
• Sedation should only be used with close monitoring 1
• Infused sedative/anxiolytic drugs should only be used in an HDU or ICU setting 1

Special Considerations

Cardiovascular Support

• In cases of cardiovascular collapse, fluid resuscitation should be initiated promptly 1
• For severe cardiovascular collapse, consider inotropes and vasopressors:
  • Dopamine and epinephrine may be preferable to norepinephrine due to their additional tachycardic actions 1
  • Dopamine can be administered at 2-20 μg/kg/min and titrated to increase systolic blood pressure 1

End-of-Life Considerations

• For patients at the end of life requiring palliative sedation, midazolam is often the first choice 1
• If mild sedation is ineffective, deeper levels of sedation should be implemented, especially in cases of refractory suffering when death is imminent 1
• For patients who are imminently dying, routine monitoring of vital signs is not necessary; the only critical parameters are those pertaining to comfort 1

Potential Complications and Management

• Excessive single doses or rapid IV administration of midazolam may result in respiratory depression, airway obstruction, and/or arrest 2
• The risk of these effects is increased in debilitated patients, those receiving concomitant CNS depressants, and patients without an endotracheal tube 2
• In case of respiratory depression, consider reducing the sedation dose or, if necessary, careful administration of a benzodiazepine antagonist (flumazenil) 1
• For patients receiving oxygen during procedures, significant arterial oxygen desaturation (SpO2 <90% or fall of 4% or more that is prolonged) should be corrected by supplemental oxygen 1

Remember that patient response to sedative agents and resultant respiratory status is variable. Sedation is a continuum, and patients may move easily from light to deep sedation with potential loss of protective reflexes 2.