Is capnography used by ED nurses? It may give life-saving information

Valuable tool not routinely used in ED

Is your intubated patient being transporte d for radiological studies? This increases the chance of disastrous consequences due to an unrecognized displaced or dislodged endotracheal (ET) tube, warns Catherine Payne, RN, MSN, CCRN, CEN, an ED nurse at the University of California Davis Medical Center in Sacramento.

"Partial dislodgments of tubes have been found to be several times more dangerous to patients than complete removal of the tube," she says, explaining that capnography can prevent life-threatening situations due to early recognition of tube displacement.

"We all know, and studies are showing, that when we move a patient, there is a risk of ET tube displacement," says Sean Hall, RN, an ED nurse at Mount Desert Island Hospital in Bar Harbor, ME, who teaches waveform capnography as a Maine Emergency Medical Services (EMS) paramedic instructor. "With waveform capnography, displacement of an ET tube is detected almost instantly."

If there is a change in the patient's respiratory status, adds Hall, capnography, coupled with good respiratory assessment skills, can save a patient's life due to early intervention.

Capnography provides a continuous confirmation of tube placement, says Payne, and a way to maintain ETCO2 levels to avoid hyperventilation and hypocapnia. "Pulse oximetry can take several minutes to detect changes in saturation, whereas capnography can reflect changes in about 10 seconds," she says.

More critically ill in ED

Capnography can alert you to low values of carbon dioxide, which may indicate the need for more aggressive therapeutic interventions, says Payne, whose ED implemented a standard of care in 2008 requiring ETCO2 monitoring for all intubated patients.

Critically ill patients are staying longer in the ED due to a lack of available staffed intensive care unit (ICU) beds, says Payne, and the standard of care should be the same in the ED as in the ICU. "Capnography is one example of an adjunct therapy needed to assist in monitoring patients to prevent potential complications," she says.

There are many potential complications associated with mechanical ventilation, she adds, adding that the artificial airway poses a risk for obstruction, displacement, or dislodgment. "This requires ED nurses to rapidly identify a life-threatening situation that requires immediate intervention," she says.

Follow EMS lead

Payne surveyed 94 emergency nurses caring for intubated patients who had been trained on the use of capnography, and 95% agreed that capnography improved patient care.1

"This provides evidence that monitoring intubated patients with capnography is considered necessary by ED nurses," says Payne, noting that this tool isn't routinely used by the ED nurse, despite recommendations from several medical societies in support of the use of ETCO2 monitoring.

ED nurses "should follow the EMS lead," according to Hall, adding that the expense of the technology is one reason capnography isn't widely used in smaller EDs.

"The standard in pre-hospital care has risen to using waveform capnography," says Hall. "Many EMS agencies are already ahead of the curve, with training and equipment in place."

New protocols for Maine EMS are in effect, he reports, which require that any patient with a transglottic device or ET tube be placed on either adult or pediatric use waveform capnography.

Some hospitals have the capability to do waveform capnography, adds Hall, which he says is especially useful in traumatic brain injury, sepsis, and respiratory emergencies.

"With capnography, one is able to prevent hyperventilation in a traumatic brain injury by keeping ETCO2 between 35 and 45," he explains. "As we all know, hyperventilation can cause increased intercranial pressures, which can result in poor outcomes in those patients."

Some hospitals have the equipment and policies in place, says Hall, but may lack the education component. If ED nurses become proficient in capnography, says Hall, this will greatly improve management of ventilated patients, and the use of side stream waveform capnography will greatly improve the care of respiratory patients.

"I personally have used this technology with outstanding results," says Hall. "Used in conjunction with a pulse oximetry, it can show improvement or decline. This can have a dramatic impact on the patient's course of treatment." (See related story, below, on use in patients with respiratory compromise.)


  1. Payne C. Nurses' perceptions on the use and effectiveness of capnography in the emergency department. February 11, 2011. California State University-Chico, Digital Repository.


For more information on use of capnography by ED nurses, contact:

  • Anne Eizyk, BA, RN, CEN, Emergency Department, St. Elizabeth Healthcare, Florence, KY. Phone: (859) 212-5441. Fax: (859) 212-4337. E-mail:
  • Sean Hall, RN/Paramedic/CCT, Emergency Department, Mount Desert Island Hospital, Bar Harbor, ME. Phone: (207) 288-8439. E-mail:
  • Catherine Payne, RN, MSN, CCRN, CEN, University of California Medical Center, Sacramento. Phone: (916) 686-2571. E-mail:

Monitoring ETCO2 may mean fewer treatments

Using tool can be challenging

Capnography "is a fantastic tool that is not being utilized enough in the ED," says Anne Eizyk, BA, RN, CEN, an ED nurse at St. Elizabeth Healthcare in Florence, KY.

After months of reading about capnography use in the ED and studying waveforms, Eizyk was finally able to use the tool on two nonconscious sedation patients and apply the information to her assessments. "Using the end-tidal carbon dioxide [ETCO2] monitor in our department is sometimes a bit of a challenge," she explains, adding that hospital policy requires that ETCO2 be monitored while giving conscious sedation.

"But using it in patients with respiratory compromise can also give us very useful information, if one is familiar with the implications of the waveforms," she says.

However, although there are two ETCO2 monitors in the ED, only one has the capability of monitoring the waveform, she explains. "It can be piggybacked onto any of our cardiac monitors, but sometimes it takes time to locate it. It seems that it is often out for repair," says Eizyk. The other monitor is connected to an infusion syringe pump for patient-controlled anesthesia, and because it only displays numbers, it is only used when administering conscious sedation, she explains.

Despite these challenges, Eizyk was able to locate the monitor and the tubing before receiving a woman in her 50s in respiratory distress who was brought in by paramedics. The patient presented wearing a 100% non-rebreather, sitting in a tripod position, and was tachypneic and tachycardic with a pulse oximetry in the low 80% range.

"Surprisingly, I heard more lung sounds than I thought I would, but they were decreased," says Eizyk, who took the patient off the non-rebreather and placed her on 4 L oxygen per the ETCO2 nasal cannula, and studied the waveform.

"From reading this waveform, I could deduce that despite her increased respiratory rate, she was still retaining a large amount of carbon dioxide," says Eizyk. "Because of her lung disease, she was not able to fully exhale. Her baseline remained elevated."

Monitoring the ETCO2 waveform probably saved the patient from getting a few more bronchodilator treatments in the ED, she says, adding that just two treatments were given.

With a few bronchodilator treatments, Eizyk saw that the baseline was decreasing, the waves were becoming less tall and narrow, and her respiratory rate was becoming normal. "This information was more helpful to me than just following her pulse oximetry or constantly listening to her lung sounds, which really didn't change that much after therapy," says Eizyk.