8.3 Disaster Preparedness & Interprofessional Care

Disaster Preparedness and Crisis Standards of Care

In disaster scenarios, such as a mass casualty incident (MCI), toxic gas exposure, or a respiratory pandemic, the demand for critical care resources can quickly exceed availability. Hospitals transition through three levels of care:

1. Conventional Care: Normal daily operations and resource availability.
2. Contingency Care: Adapting practices to maintain standard care (e.g., using transport ventilators for long-term ICU care).
3. Crisis Standards of Care: Resource allocation protocols are activated to maximize the number of lives saved under severe shortages.

Ventilator Allocation and Triage Protocols

When the demand for mechanical ventilators exceeds the hospital's physical supply, an ethical framework based on utilitarianism (maximizing the greatest good for the greatest number) is enacted.

• SOFA Score: Triage protocols utilize the Sequential Organ Failure Assessment (SOFA) score to objectively evaluate organ system function (respiratory, coagulatory, hepatic, cardiovascular, renal, and neurological). Patients with the lowest SOFA scores (highest likelihood of short-term survival) are prioritized for ventilator allocation.
• The Triage Officer: Ethical guidelines require that a designated Triage Officer or Triage Committee—independent of the patient's direct care team—makes all decisions regarding ventilator allocation or withdrawal. This prevents conflicts of interest for the bedside clinician. The RT executes these decisions but does not make the final allocation determination.
• Alternative Ventilator Use: The RT must adapt by repurposing non-traditional devices for invasive ventilation, including anesthesia machines, high-end transport ventilators, and bi-level positive airway pressure (BiPAP) machines configured with appropriate alarms and filters.

Bulk Oxygen Systems and Conservation Protocols

A major vulnerability in respiratory disasters is the hospital's bulk liquid oxygen supply.

• Vaporization Limits: Liquid oxygen is stored at $-184^\circ\text{F}$ ($-120^\circ\text{C}$). Before entering the hospital pipeline, it must pass through ambient air vaporizers to convert it to gas. Under extreme demand (e.g., dozens of patients receiving high-flow nasal cannula at 60 L/min), the vaporization rate is exceeded, causing the vaporizers to freeze. This drops pipeline pressure, risking a facility-wide loss of oxygen.
• Oxygen Conservation Protocol:
  • Permissive Hypoxemia: Adjust target oxygen saturations to 88% to 92% (or $PaO_2$ of 55-80 mmHg) for all patients without carbon monoxide poisoning, acute coronary syndrome, or pregnancy.
  • HFNC Restrictions: Restrict the use of High-Flow Nasal Cannula (HFNC) and non-invasive ventilation, which consume up to 60-80 L/min of 100% oxygen. Shift stable patients to reservoir masks or standard nasal cannulas.
  • Ventilator Bias Flow: Turn down bias flow on mechanical ventilators if adjustable, as continuous bias flow consumes oxygen during expiration.

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Interprofessional Communication and Collaboration

Sentinel events in the ICU are frequently linked to communication breakdowns. Standardizing handoffs and daily rounding is essential.

The SBAR Communication Tool

The Situation-Background-Assessment-Recommendation (SBAR) framework provides a structured format for conveying critical clinical information:

• Situation: State the immediate reason for the contact.
  • Example: "Dr. Chen, this is Sarah from Respiratory. I am calling regarding Mr. Davis in ICU Bed 6. He has developed sudden respiratory distress and his oxygen saturation has dropped to 82%."
• Background: Provide relevant clinical history.
  • Example: "He is a 58-year-old male with severe ARDS who has been intubated for 3 days. He is currently on Volume Control ventilation with a PEEP of 14 cm H2O and $FiO_2$ of 60%."
• Assessment: Share your clinical evaluation of the situation.
  • Example: "His peak inspiratory pressure has jumped from 32 to 52 cm H2O, and his plateau pressure has risen from 26 to 45 cm H2O. I note absent breath sounds on the left side with tracheal deviation to the right. I suspect a left-sided tension pneumothorax."
• Recommendation: Propose a specific action plan.
  • Example: "I recommend an immediate needle decompression followed by a chest tube insertion. I have the decompression kit at the bedside. Do you agree?"

Daily Multidisciplinary Rounds (MDR)

Bedside rounding involves the intensivist, bedside nurse, respiratory therapist, pharmacist, and dietitian. During MDR, the RT's role is to present a concise respiratory profile:

1. Current Vent Settings: Mode, set rate vs. total rate, tidal volume, PEEP, $FiO_2$, and peak/plateau pressures.
2. Weaning Parameters: Present spontaneous tidal volume, respiratory rate, and the Rapid Shallow Breathing Index (RSBI) (f/Vt, where a value $< 105$ predicts weaning success).
3. Daily Awakening Coordination: Coordinate the daily Sedation Vacation (managed by nursing) with the Spontaneous Breathing Trial (SBT, managed by RT).
4. Airway Integrity: Report recent cuff pressures (maintained between 20 and 30 cm H2O to prevent tracheal necrosis and micro-aspiration) and the position of the ETT at the lip.

Therapist-Driven Protocols (TDPs)

TDPs are physician-approved clinical algorithms that authorize the RT to assess the patient and adjust respiratory therapies independently.

• Benefits: TDPs reduce the duration of mechanical ventilation, lower VAP rates, and decrease ICU length of stay by allowing immediate clinical adjustments without waiting for a physician's written order. Examples include oxygen titration protocols, bronchodilator weaning protocols, and ventilator liberation protocols.