Capnography: Current and Future Use by EMS Presented by: Tim Ludwig EMT-P

Objective To provide an overview of capnography and its uses in the pre-hospital setting. Define terms that are associated with capnography and cardio/respiratory function Review the physiological process’ Understand/Apply how capnography can be used today for first responders.

What is Capnography? Capnography = the amount of carbon dioxide measured at the end of each exhaled breath. Measured by both numeric value and waveforms. – Capnometer: the numeric measurement of CO2 – Capnogram: the waveform that is displayed – ETCO2/PetCO2: the level of partial pressure of carbon dioxide released at the end of expiration.

Example of Capnography Waveform

LifePak 15 Normal respiratory pattern and waveform capnography displayed

Cannula utilized to monitor ETCO2 levels Can record exhaled CO2 from the nostrils as well as from the mouth.

Normal Respiratory Waveform

ETCO2 vs. PACO2 ETCO2 (PetCO2) Detected via capnography Appears in the waveform/numeric values caputured on monitor with exhaled breaths Normal ETCO2 values are mmHg. Some experts may claim normal 30-43mmHg. PACO2 From Arterial Blood Gas (ABG) samples Normal PACO2 values are 35-45mmHg

Capnography Vs. Pulse Oximetry Pulse Oximetry measures the results of breathing in oxygen. Measured in the tissues. (cap refill, finger pulse oxymetry) Capnography measures the results of the use of oxygen with CO2 being the byproduct and measured with the exhaled breath.

Why is this important to me? Provides the ability to monitor the effectiveness of CPR specifically with compressions. 100% accuracy with confirmation of well placed advanced airway. Changes in patient condition can be displayed immediately. Ability to assist with additional medical finding with ongoing assessment.

Effectiveness of CPR Effective compression measured by CO2 measurment of 10 – 20 mmHG Ineffective compressions will show CO2 measurement <10 mmHG Time to switch to restore effective CPR. The most basic techniques, can often times be overlooked.

Placement of Advanced Airway Capnography will confirm proper ET Tube placed more efficiently than colormetric devices. Capnography is recommended with utilization of CPAP devices. Can/should be measured whenever oxygen is placed on patient regardless of the delivery method.

Hypoventilation vs. Hyperventilation

Decreased ETCO2 Increased Rate Increased tidal volume Decreased metabolic rate Fall in body temp Decreased cardiac output Diabetic Ketoacidosis

Increased ETCO2 Levels Decrease in respiratory rate Decrease in tidal volume Increase in metabolic rate Overdose Sedation Intoxication Posticatal Head trauma Stroke Rise in body temperature

Future of Capnography in EMS Research continues to justify use in pre- hospital settings. Recent studies for the detection of pulmonary emboli. Can utilize to assist anxiety patients respirations. Possible use to assist in triage of patients during a bioterrorism attack.