Infiltration: cool, pale, swollen site with a slow drip — stop and remove.
Before you read
Test yourself first: 5 questions
Question 1 of 5
What is the purpose of the gastric access port found on many supraglottic airway devices?
Answer: A. The gastric port opens at the device tip in the upper esophagus, so a gastric tube can be passed to vent air and fluid from the stomach — lowering aspiration risk and easing ventilation. It is not a medication or capnography channel; capnography attaches at the ventilation port, and the cuff has its own pilot line.
Question 2 of 5
A patient with an opioid overdose is on nasal-cannula capnography. Which change gives the EARLIEST warning that she is about to stop breathing?
Answer: A. Capnography reports each breath as it happens: slowing respirations appear as taller, widely spaced waveforms, and apnea as a flat line — well before oxygen reserves are used up. Pulse oximetry lags by minutes, especially on supplemental oxygen, and pupil or heart-rate findings do not track breathing breath by breath.
Question 3 of 5
Gastric contents begin flowing out of the gastric access port of a correctly placed supraglottic airway. Chest rise and the capnography waveform are unchanged. The correct interpretation is that:
Answer: A. The gastric channel exists to let stomach air and fluid escape rather than rise into the pharynx; drainage with preserved chest rise and waveform means the device is working. It does not mean tracheal placement, which would show no gastric flow, nor cuff failure, and stopping ventilation for an apneic patient allows hypoxia while achieving nothing.
Question 4 of 5
Waveform capnography on an intubated patient shows a sudden fall from 38 to near zero with no waveform. The most likely cause is:
Answer: A. An abrupt loss of waveform means either no air is passing the sensor or no blood is delivering CO2 to the lungs — a dislodged tube, or arrest. Both demand immediate action. Hypoventilation raises the value rather than eliminating it, and bronchospasm changes the waveform's shape while preserving it.
Question 5 of 5
A patient with severe bronchospasm shows a capnography waveform with a steep, sloping upstroke. This 'shark fin' shape reflects:
Answer: A. The sloping upstroke comes from alveoli emptying at different rates through narrowed lower airways, so the plateau never becomes flat. It is a shape change, which distinguishes it from a leak or a misplacement — those alter the amplitude or abolish the waveform entirely.
Keep the streak going with more questions like these, each with a full rationale.
Key points to remember
- Infiltration: cool, pale, swollen site with a slow drip — stop and remove.
- Circulatory overload: crackles and distended neck veins — slow to a keep-open rate.
- IO in the proximal tibia or humeral head; never in a fractured bone.
- A continuous capnography waveform is the best confirmation of an advanced airway.
- Normal end-tidal CO2 is 35–45 mmHg; a sudden rise during CPR suggests ROSC.
Field priorities
- Never re-advance a needle into its catheter.
- Uncontrolled bleeding without head injury: aim for a radial pulse, not a normal pressure.
- Intubated and worsening: DOPE — displacement, obstruction, pneumothorax, equipment.
Coaching the patient
- Drip rate = volume × drop factor ÷ minutes.
Red flags: act now
- Waveform lost after moving the patient
- Right-only breath sounds (tube too deep)
Vascular Access & Capnography: FAQs
What are the priority actions for Vascular Access & Capnography in the field?
Never re-advance a needle into its catheter. Uncontrolled bleeding without head injury: aim for a radial pulse, not a normal pressure. Intubated and worsening: DOPE — displacement, obstruction, pneumothorax, equipment.
What findings in Vascular Access & Capnography change your plan or your transport decision?
Waveform lost after moving the patient. Right-only breath sounds (tube too deep).
What do I need to know about Vascular Access & Capnography for the NREMT?
Infiltration: cool, pale, swollen site with a slow drip — stop and remove. Circulatory overload: crackles and distended neck veins — slow to a keep-open rate. IO in the proximal tibia or humeral head; never in a fractured bone. A continuous capnography waveform is the best confirmation of an advanced airway.
What should the crew communicate or document for Vascular Access & Capnography?
Drip rate = volume × drop factor ÷ minutes.
