Showing posts with label ETCO2. Show all posts
Showing posts with label ETCO2. Show all posts

Sunday, October 19, 2025

Understanding MARCH - The Relevance of Respiratory Assessment

Image retrieved from tccc.org.ua

From the MARCH Mnemonic Series – Tactical Trauma Care for EMS Providers

After controlling massive hemorrhage and ensuring a patent airway, the next priority in the MARCH sequence is Respiration. 

Effective breathing is critical for oxygen delivery and carbon dioxide removal. When trauma impairs the chest wall or lungs, hypoxia and shock can develop rapidly - even when the airway is clear.

In tactical or prehospital settings, respiratory compromise is often caused by thoracic injury, such as a gunshot, stab wound, or blast trauma. 

These injuries can lead to life-threatening conditions like tension pneumothorax or open chest wounds, both of which are preventable causes of death when identified and treated early.

This article - the third in a five-part series - will focus on that next critical step: 

R – Respiration

Respiration refers to the body’s ability to move air into and out of the lungs and to exchange gases at the alveolar level. 

Any disruption - mechanical, anatomical, or physiological - can cause hypoxia and threaten survival. 

The responder’s task is to rapidly assess, seal, decompress, and support breathing as needed.

Image retrieved from tccc.org.ua

Principles of Respiratory Management

1. Assess the Casualty’s Breathing

Begin by evaluating rate, depth, and effort of respirations. Look, listen, and feel for:

  • Asymmetrical chest rise or movement
  • Difficulty speaking, gasping, or labored breathing
  • Cyanosis around lips or fingertips
  • Tracheal deviation, jugular venous distention, or subcutaneous emphysema
  • Penetrating trauma to the chest or upper abdomen
If you’re operating in a tactical environment, conduct this assessment as efficiently as safety allows—rapid but systematic.

2. Expose and Inspect for Chest Injuries

Visually inspect the anterior, lateral, and posterior thorax for entry and exit wounds, contusions, or deformities. In low-light or confined spaces, gloved hands may detect what the eyes can’t.

  • Sucking chest wounds (open pneumothorax) occur when air enters the pleural space through a chest wall defect.
  • These must be sealed immediately with a vented or occlusive chest seal to prevent the progression to tension pneumothorax.
Modern products like the HyFin® Vent Chest Seal or FoxSeal™ are designed for field reliability and are standard in most tactical trauma kits.

Image retrieved from tccc.org.ua

3. Manage a Tension Pneumothorax

A tension pneumothorax occurs when air becomes trapped in the pleural space and cannot escape, collapsing the lung and compressing the heart and great vessels.
Signs may include:

  • Severe respiratory distress
  • Decreased or absent breath sounds on one side
  • Hypotension and tachycardia
  • Tracheal deviation (a late sign)
Image retrieved from tccc.org.ua

Intervention:

If tension pneumothorax is suspected and equipment/training allow, perform needle decompression:

  • Use a 14-gauge, 3.25-inch (8.25 cm) needle or catheter.
  • Insert into the 5th intercostal space, anterior axillary line (or 2nd intercostal space, midclavicular line if indicated).
  • Listen for escaping air and observe for improvement in breathing and perfusion.
Always reassess, if symptoms recur, repeat decompression or prepare for chest tube insertion at higher care levels.

Image retrieved from tccc.org.ua

4. Support Oxygenation and Ventilation

If available and appropriate, administer supplemental oxygen to maintain SpO₂ above 94%. 

For inadequate respirations, assist with bag-valve-mask (BVM) ventilation while maintaining airway alignment. In prolonged field care, consider monitoring SpO₂ and ETCO₂, if resources allow, to guide ongoing management.

5. Continue Monitoring and Reassessment

The chest is dynamic, bleeding, air leakage, or mechanical disruption can recur with movement or time. Reassess chest rise, breath sounds, and patient condition frequently during evacuation.

Key Takeaway for EMS and Tactical Providers

Thoracic trauma demands vigilance. While hemorrhage and airway compromise often draw attention first, unrecognized respiratory failure can kill just as quickly. The tactical provider must be proficient in identifying chest injuries, applying chest seals, and performing needle decompression when indicated.

In short: find the holes, seal the leaks, relieve the pressure, and keep the oxygen moving.

Coming Up Next: Part Four – Circulation

Once bleeding is controlled, the airway is secure, and breathing is restored, it’s time to assess circulation—the body’s ability to perfuse vital organs. 

In Part Four of our MARCH series, we’ll explore recognition and management of shock, fluid resuscitation strategies, and maintaining perfusion in both field and tactical environments.

Because after oxygen, the mission is to keep it flowing where it matters most.

Further Reading:

American College of Surgeons Committee on Trauma. (2022) Advanced Trauma Life Support (10th Ed). Chicago, IL: American College of Surgeons.

Bledsoe, B. E., Cherry, R. A. & Porter, R. S (2023) Paramedic Care: Principles and Practice (6th Ed) Boston, MA: Pearson Education

Butler, F. K. (2017) Tactical Combat Casualty Care: Beginnings. Wilderness & Environmental Medicine 28 (2S): S12-S17. 
Retrieved from https://pubmed.ncbi.nlm.nih.gov/28284483/ on October 8, 2025

Butler, F. K., Bennett, B., & Wedmore, C. I. (2017) Tactical Combat Casualty Care and Wilderness Medicine: Advancing Trauma Care in Austere Environments. Emergency Medicine Clinics of North America 35 (2): 391-407. Retrieved from https://pubmed.ncbi.nlm.nih.gov/28411934/ on October 8, 2025

Committee on Tactical Combat Casualty Care (2023) Tactical Combat Casualty Care (TCCC) Guidelines for Medical Personnel. Defense Health Agency, Joint Trauma System. Retrieved from https://jts.health.mil on October 8. 2025

National Association of Emergency Medical Technicians NAEMT (2020) TECC: Tactical Emergency Casualty Care Course Book (2nd Ed). Burlington, MA: Jones & Bartlett Learning

National Association of Emergency Medical Technicians NAEMT (2023) Tactical Emergency Casualty Care (TECC) Guidelines. NAEMT Education Division

National Association of Emergency Medical Technicians NAEMT (2025) PHTLS: Prehospital Trauma Life Support, Military Edition eBook (10th Ed). Burlington, MA: Jones & Bartlett Learning 

Saturday, May 25, 2024

EMS Research - Chest Decompressions: The Driver of CPR Efficacy


The study aims was to optimize cardiopulmonary resuscitation (CPR) efficacy by investigating the relationship between key CPR metrics: compression rate, depth, and recoil velocity.

The goal was to model the impact of these variables on CPR effectiveness, particularly through their influence on end-tidal carbon dioxide (ETCO2), which is a marker of perfusion.

The study emphasizes the crucial role of chest recoil in CPR effectiveness. The findings suggest that CPR guidelines should prioritize maximum chest recoil to improve hemodynamics and increase the chances of survival during cardiac arrest.

The research advocates for an increased focus on chest recoil in CPR training and guidelines, potentially leading to improved outcomes in cardiac arrest scenarios by enhancing the quality of perfusion during resuscitation efforts.
Further Reading:
Chandran, K., AlgazeGonzalez, I.M., Wang, S., & Davis, D.P. (2024) Chest Decompressions - the Driver of CPR Efficacy: Exploring The Relationship Between Compression Rate, Depth, Recoil Velocity & End-Tidal CO2. Taylor & Francis Online Accessed May 25, 2024

Thursday, February 15, 2024

EMS Patient Monitoring - Capnography 4


Understanding the capnography waveform is essential. A consistent waveform indicates proper ventilation, while irregularities may signal airway or respiratory issues.

Considerations:

Equipment Calibration: Regular calibration of capnography equipment is essential to maintain accuracy in CO2 measurements.

Interference with Nasal Cannula: Nasal cannulas may result in lower ETCO2 readings due to air dilution. Consider using an alternative sampling method if necessary.

Low Perfusion States: In low perfusion states, such as during cardiac arrest, capnography may be less reliable in reflecting true ETCO2 levels.

Temperature Compensation: Capnography measurements are temperature-dependent. Providers should be aware of the need for temperature compensation to ensure accurate readings.

Limitations:

Airway Anomalies: Some airway anomalies or pathologies may affect capnography readings. Providers should be cautious in interpreting results in such cases.

Equipment Malfunction: Malfunctions in the capnography equipment can lead to inaccurate readings. Regular maintenance and checks are necessary.

Rebreathing: Rebreathing or partial rebreathing masks can result in elevated ETCO2 levels, affecting the accuracy of monitoring.

Sampling Rate: Inadequate sampling rates may result in delayed detection of changes in ETCO2 levels. Ensure the capnography device has an appropriate sampling rate.

Pulmonary Embolism: In cases of massive pulmonary emboli, capnography may show a decrease in ETCO2 due to reduced perfusion to the lungs.

EMS providers should undergo proper training to interpret capnography data accurately and be aware of the limitations and special considerations in various clinical scenarios.

Regular education and updates on capnography technology are crucial to providing optimal patient care.

Further Reading:

Capnography: Principles and Practice by Michael K. Copeland

Capnography, King of the ABC’s: A Systematic Approach for Paramedics" by Troy Valente

Paramedic Care: Principles & Practice: by Bryan E. Bledsoe, Robert S. Porter, and Richard A. Cherry


Tuesday, February 13, 2024

EMS Patient Monitoring - Capnography 3


ETCO2 monitoring is a valuable tool for EMS Providers as it provides real-time information about a patient's respiratory status and overall physiological condition. Here's how ETCO2 is useful for EMS providers:
Ventilation Assessment: ETCO2 levels reflect the adequacy of ventilation. Monitoring ETCO2 helps EMS providers assess whether a patient is effectively eliminating CO2 through ventilation.
Confirmation of Airway Placement: ETCO2 is commonly used to confirm proper placement of an endotracheal tube or other advanced airway devices. A sudden increase in ETCO2 during intubation indicates successful placement within the trachea, whereas low or absent readings may suggest esophageal or misplaced airway.
Circulatory Status Indicator: Changes in ETCO2 levels can provide insight into the patient's circulatory status. A sudden decrease in ETCO2 may indicate reduced cardiac output, potentially signaling cardiac arrest or severe shock.
Monitoring During CPR: ETCO2 monitoring is crucial during cardiopulmonary resuscitation (CPR). A sudden increase in ETCO2 levels during CPR may indicate return of spontaneous circulation (ROSC), while persistently low levels may suggest poor perfusion and the need for intervention.
Detection of Respiratory Distress or Failure: ETCO2 is a sensitive indicator of respiratory distress or failure. A sudden decrease in ETCO2 may signal respiratory compromise, allowing providers to intervene promptly.
Prognostic Tool: Persistent low ETCO2 levels during CPR are associated with a poorer prognosis. Monitoring ETCO2 trends can help providers make informed decisions about the effectiveness of resuscitative efforts.
Guidance During Procedural Sedation: EMS providers can use ETCO2 monitoring to ensure adequate ventilation during procedural sedation. This is particularly important when administering sedatives or analgesics that may depress respiratory function.
Trauma Assessment: In trauma patients, ETCO2 monitoring can aid in identifying respiratory distress due to thoracic injuries or other traumatic conditions.
Early Detection of Respiratory Complications: Monitoring ETCO2 allows for the early detection of respiratory complications, such as hypoventilation or respiratory depression, enabling timely intervention.
Further Reading:
Capnography: Principles and Practice by Michael K. Copeland
Capnography, King of the ABC’s: A Systematic Approach for Paramedics" by Troy Valente

Paramedic Care: Principles & Practice" by Bryan E. Bledsoe, Robert S. Porter, and Richard A. Cherry 

Sunday, February 11, 2024

EMS Patient Monitoring - Capnography 2


The choice of monitoring device depends on factors such as the patient's condition, the level of invasiveness required, and the specific clinical scenario.

Mainstream and sidestream capnography are the most commonly used methods for continuous ETCO2 monitoring.

The devices used to measure end-tidal CO2 (ETCO2) typically include:

Capnometers: These are basic devices that measure and display the numerical value of ETCO2. They are commonly used in various medical settings.

Capnographs: More advanced devices that not only display the numerical value of ETCO2 but also provide a continuous graphical representation known as the capnogram.

The capnogram displays the CO2 concentration over time, showing inhalation, exhalation, and the phase where little or no CO2 is present (representing the end-tidal point).

Mainstream Capnography: With mainstream capnography, the sensor is placed directly in the patient's airway, usually at the end of an endotracheal tube or an adapter connected to a ventilation device.

This type of capnography provides immediate and accurate measurements but may add dead space to the breathing circuit.

Sidestream Capnography: With sidestream capnography, a sampling tube diverts a small portion of the patient's exhaled air to a separate sensor away from the patient.

This method is less invasive and reduces the dead space in the breathing circuit. It is commonly used in non-intubated patients and during procedural sedation.

Colorimetric Devices: These devices provide a color change based on the CO2 concentration. They are often used as a quick and cost-effective method for verifying endotracheal tube placement but may not provide continuous monitoring.

Portable Capnography Devices: There are compact and portable capnography devices designed for prehospital and emergency use by EMS providers. These devices are lightweight, battery-operated, and provide essential monitoring capabilities in various environments.

Further Reading:

Capnography: Principles and Practice by Michael K. Copeland

Capnography, King of the ABC’s: A Systematic Approach for Paramedics" by Troy Valente

Infinium (ND) What is a Capnograph https://infiniummedical.com/what-is-capnography/ Accessed January 16, 2024

Paramedic Care: Principles & Practice" by Bryan E. Bledsoe, Robert S. Porter, and Richard A. Cherry


Friday, February 09, 2024

EMS Patient Monitoring - Capnography 1


Widely embraced across diverse medical settings, including the exigencies of emergency medical services, the precision of intensive care units, the intricacies of operating rooms, and the nuanced demands of procedural sedation, capnography emerges as a multifaceted sentinel for healthcare providers.

Capnography is an indispensable asset within the realm of prehospital and emergency medical care, serving as a dynamic window into a patient's physiological landscape. This monitoring technique engages in the continuous, real-time measurement and graphical representation of carbon dioxide (CO2) concentration, specifically known as end-tidal CO2 (ETCO2), within a patient's exhaled breath.

By offering an unbroken stream of insights into both respiratory and circulatory dynamics, capnography provides a comprehensive understanding of a patient's evolving physiological status.

End-Tidal CO2 (ETCO2), the focal point of capnography, unveils the partial pressure or concentration of carbon dioxide at the culmination of each exhaled breath. This metric, expressed in millimeters of mercury (mmHg) or as a percentage, furnishes EMS providers with real-time, actionable information regarding a patient's respiratory well-being.

As a consequence, ETCO2 monitoring emerges as a linchpin in the delivery of timely and informed interventions, ensuring the optimization of patient care in critical and time-sensitive situations.

The word ‘capnography’ has its roots in Greek. The term is derived from the Greek word ‘kapnos’ meaning ‘smoke’, and the suffix ‘-graphy’, which refers to the process of recording. The name reflects its focus on the measuring of carbon dioxide which, historically, has been associated with the term ‘smoke’ due to its visible presence in combustion processes

Further Reading:

Capnography: Principles and Practice by Michael K. Copeland

Capnography, King of the ABC’s: A Systematic Approach for Paramedics" by Troy Valente

Paramedic Care: Principles & Practice" by Bryan E. Bledsoe, Robert S. Porter, and Richard A. Cherry