Respiratory and Airway Management — Flashcards

Flashcard 41: Thiopentone produces dose-related central respiratory depression, producing a characteristic ventilatory pattern called '_____''

Answer: double apnea

Flashcard 42: _____ faced Ring-Adair-Elwyn (RAE) endotracheal tube is preferred for oral and dental surgeries

Answer: North

Flashcard 43: HFNC _____ the positive end-expiratory pressure (PEEP), and reduces the work of breathing

Answer: increases

Flashcard 44: If an airway fire occurs during laser airway surgery, it should be extinguished with _____

Answer: saline

Flashcard 45: On capnography, a progressive increase in the EtCO2 plateau height (while maintaining a normal waveform shape) represents: _____

Answer: Hypoventilation

Extra: Hypoventilation results in CO2 retention, which manifests on capnography as a progressive increase in the height of the EtCO2 plateau. Conversely, hyperventilation leads to a decrease in EtCO2 levels.

Flashcard 46: What is the recommended tidal volume (Vt) for standard lung-protective mechanical ventilation?

Answer: 6-8 mL/kg of Ideal Body Weight (IBW)

Extra: Lung-protective ventilation aims to prevent volutrauma and ventilator-induced lung injury (VILI). It is critical to calculate the volume based on **Ideal Body Weight (IBW)** based on height and gender, rather than actual weight, to avoid overdistension. In patients with ARDS, even lower volumes (4-6 mL/kg IBW) are recommended.

Flashcard 47: Which anesthetic technique/agent is often preferred for maintenance during laser airway surgery to minimize the risk of airway fire?

Answer: Total Intravenous Anesthesia (TIVA) with Propofol

Extra: Maintenance with volatile agents (e.g., Sevoflurane, Isoflurane) is also acceptable as they are non-flammable. However, **TIVA with Propofol** is often preferred to facilitate lower oxygen concentrations and tubeless techniques (e.g., high-frequency jet ventilation or spontaneous ventilation). **Key Laser Safety Points:** 1. **Avoid Nitrous Oxide (N2O):** It supports combustion. 2. **Low FiO2:** Keep oxygen concentration at the minimum required (usually <30%). 3. **Laser-resistant ETT:** If using a tube, use a specially wrapped or copper/stainless steel tube with saline in the cuff.

Flashcard 48: For laser airway sx, the concn of inspired O2 should be as _____ as possible

Answer: low

Flashcard 49: A biphasic or "dual-peak" capnography waveform (double-sloped expiratory plateau) is characteristic of:

Answer: Single lung transplant

Extra: A biphasic or "dual-peak" capnogram (double-sloped expiratory plateau) occurs in single-lung transplant patients because the native and transplanted lungs have different compliance and resistance (different time constants), leading to asynchronous emptying.

Flashcard 50: Phase _____ of normal capnography is sharp rise in pCO2 to a plateau indicating sampling of transitional gas between the airways and alveoli

Answer: II