What is the recommended protocol for procedural sedation?

Comprehensive Guide to Procedural Sedation Protocol

Pre-Procedure Patient Evaluation

Conduct a focused assessment examining airway anatomy (Mallampati score, neck mobility, jaw opening), cardiovascular status (blood pressure, heart rate, rhythm), respiratory function (baseline oxygen saturation, lung sounds), and current medications including anticoagulants, opioids, and benzodiazepines. 1 Document ASA Physical Status classification, as ASA-PS III-IV patients require dose reductions of approximately 80% and slower titration. 1

Critical Assessment Components:

• Airway evaluation: Look specifically for difficult facial/neck anatomy, limited mouth opening (<3 cm), short thyromental distance, obesity with thick neck, and history of obstructive sleep apnea 1
• Cardiovascular risk: Identify patients with compromised myocardial function, intravascular volume depletion, or abnormally low vascular tone (sepsis), as these patients are more susceptible to hypotension 2
• Fasting status: Document time and nature of last oral intake, but do not delay urgent or emergent procedures based on fasting time alone 1

The evidence clearly shows that aspiration during procedural sedation is extremely rare, and preprocedural fasting has no impact on complications or outcomes. 1 In a prospective study of 1,014 children, 56% did not meet fasting guidelines yet no aspiration episodes occurred. 1

Personnel Requirements

A dedicated sedation monitor (separate from the proceduralist) must be present throughout the procedure, trained in recognizing apnea and airway obstruction. 1 This monitor may perform minor interruptible tasks once stable sedation is achieved. 1

Personnel Roles and Qualifications:

• Sedation provider: Must be trained in general anesthesia or have equivalent training in airway management and resuscitation 1
• Sedation monitor: Typically a registered nurse, must continuously observe airway patency, ventilation quality, and patient responsiveness 1
• For deep sedation: A dedicated sedation provider (not performing the procedure) is optimal, though time-sensitive emergencies may proceed with appropriate backup if the procedure can be immediately halted 1

Registered nurses with adequate training should be permitted to administer all procedural sedation medications under direct supervision of the ordering provider. 1 This includes propofol, ketamine, and other agents intended for general anesthesia.

Equipment and Emergency Preparedness

Immediately available in the procedure room: 1

• Appropriately sized airway equipment (oral/nasal airways, laryngeal mask airways)
• Positive pressure ventilation device (bag-valve-mask)
• Suction apparatus in working order
• Supplemental oxygen delivery systems
• Reversal agents: naloxone for opioids, flumazenil for benzodiazepines
• Functional defibrillator or automated external defibrillator

Within 5 minutes: Advanced airway equipment for endotracheal intubation and personnel with advanced life support skills (code blue team or equivalent) 1

Intravenous Access

Establish intravenous access before administering sedation medications. 1 The single exception is for nitrous oxide and intranasal medications, where IV access may be optional. 1 Cardiologists and most proceduralists should insist on IV access for all procedures. 1

Medication Selection and Administration

Medications NOT Intended for General Anesthesia:

Benzodiazepines (midazolam), opioids (fentanyl), and dissociative agents (ketamine) should be titrated slowly in small incremental doses. 1

Medications Intended for General Anesthesia:

Propofol, etomidate, and ketamine (when used for deep sedation) require slow titration with sufficient time between doses for peak effect assessment (approximately 2 minutes). 1

Propofol Dosing Protocol:

• MAC sedation initiation: Infuse at 100-150 mcg/kg/min for 3-5 minutes, OR administer 0.5 mg/kg slowly over 3-5 minutes 2
• MAC sedation maintenance: 25-75 mcg/kg/min initially, then decrease to 25-50 mcg/kg/min 2
• Elderly/debilitated/ASA-PS III-IV: Reduce dose to 80% of usual adult dosage; avoid rapid bolus administration 2
• Critical warning: Propofol should only be administered by those trained in general anesthesia due to significant risks 3

Ketamine Advantages:

Ketamine, propofol, methohexital, "ketofol," and etomidate are ideal for patients requiring rapid recovery and potential discharge without a responsible adult, given their rapid onset, short duration, and quick recovery times. 4

Physiologic Monitoring Protocol

Continuous Monitoring Requirements:

• Ventilation: Continual observation of respiratory rate, chest wall movement, and breath sounds 1
• Oxygenation: Continuous pulse oximetry until no longer at risk for hypoxemia 1
• Cardiac monitoring: Continuous heart rate and rhythm assessment 1
• Level of consciousness: Monitor response to verbal commands every 5 minutes during moderate sedation 1

Intermittent Monitoring:

• Blood pressure: Assess before sedation, then every 5-15 minutes during procedure and recovery 1
• More frequent monitoring required for patients with cardiovascular disease or those at higher risk 1

Capnography:

When capnography is used to directly measure ventilatory status, high-flow supplemental oxygen can be safely administered throughout the procedure, providing immediate evidence of apnea or hypopnea. 1 Without capnography, supplemental oxygen is commonly avoided to allow pulse oximetry to detect ventilatory compromise earlier. 1

Supplemental Oxygen Strategy

Administer supplemental oxygen during moderate procedural sedation unless specifically contraindicated. 1 High-flow pre-oxygenation delays oxygen desaturation by up to 6 minutes in healthy adults and 2-4 minutes in children with patent airways, permitting safe tolerance of brief respiratory depression without positive pressure ventilation. 1

Management of Complications

Respiratory Depression Protocol:

1. Stimulate patient: Encourage or physically stimulate deep breathing 1
2. Administer supplemental oxygen 1
3. Provide positive pressure ventilation if spontaneous ventilation inadequate 1
4. Administer reversal agents if airway control or ventilation remains inadequate:
   • Naloxone for opioid-induced depression 1
   • Flumazenil for benzodiazepine-induced depression 1

Critical caveat: Acute reversal of opioid analgesia may cause pain, hypertension, tachycardia, or pulmonary edema. 1 Do not use sedation regimens intended to include routine reversal. 1

Hypotension Management:

Clinically important hypotension is rare during procedural sedation in patients without serious systemic disease. 1 Patients with compromised myocardial function, volume depletion, or sepsis are more susceptible and require more frequent blood pressure monitoring. 1, 2

Recovery and Discharge Criteria

Observe patients in an appropriately staffed area until near baseline consciousness and no longer at increased risk for cardiorespiratory depression. 1

Specific Discharge Requirements:

• Monitor ventilation and circulation at regular intervals (every 5-15 minutes) until suitable for discharge 1
• Continue oxygenation monitoring until no risk for hypoxemia 1
• After reversal agents, observe sufficient time to ensure sedation doesn't recur when antagonist effect dissipates 1

For patients without a responsible adult for discharge: With appropriate medication selection (ketamine, propofol, methohexital, etomidate) and proper observation protocols, patients can be safely discharged 2-4 hours post-procedure without pharmacodynamic or pharmacokinetic justification for requiring a responsible adult. 4

Quality Improvement and Safety Culture

Implement a quality improvement process based on established reporting protocols for adverse events and unsatisfactory sedation. 1 Strengthen patient safety through team training, simulation drills, and checklist implementation. 1 Create an emergency response plan for activating code blue teams or emergency medical services. 1

Documentation Requirements:

Record level of consciousness, ventilatory status, oxygenation, and hemodynamics: 1

• Before sedative administration
• After sedative administration
• At regular intervals during procedure
• During initial recovery
• Just before discharge

Special Populations

Pediatric Patients:

• Utilize developmentally appropriate interventions to reduce fear and anxiety 1
• Enlist child life specialists when available 1
• Younger children may require higher maintenance infusion rates than older children 2
• Immobilization devices should generally be used, not as substitute for non-pharmacological interventions 1

Cardiac Patients:

High-volume cardiac catheterization laboratories frequently encounter post-cardiac arrest and cardiogenic shock patients, requiring different risk assessment than standard procedural sedation. 1 Immediate availability (<5 minutes) for endotracheal intubation is ideal, with focus on stimulation, repositioning, and bag-mask ventilation for cardiologists without intubation expertise. 1