Sunday, March 21, 2010

Use of End-tidal Co2 Monitoring to Detect Hypoventilation and Sedation in Pain Management

Statement of Problem
Pain management of the post-operative patient is important because pain control improves a patient’s ability to ambulate, deep breath, and decreases length of stay in the hospital. Pain is the fifth vital sign and is assessed in Post Anesthesia Care Unit (PACU) every fifteen minutes. Opioid use preoperatively has brought with it new challenges in pain management. Because patients are more tolerant to opioids nurses are giving higher doses of opioids than ever before. The combination of increased amounts of opioids given and anesthesia has created a new problem. Patients receiving higher doses of opioids are at risk for over sedation.

Over sedation is defined as a change in mental status, decrease in respiratory rate (hypoventilation) below ten breaths per minute, and drop in pulse oximerty (PO %) below 92%. Hypoventilation is dangerous situation which can lead to apnea, increase Co2 blood levels, and chest wall rigidity. The standard of care in the PACU for hypoventilation and sedation is to perform wake up regime and apply supplemental oxygen.

Research has shown that applying supplemental oxygen may improve the PO% reading but does not improve ventilation. Patients may have normal PO% and yet have apenic episodes. End-tidal Co2 (ETCO2) monitoring may be the solution to this problem; as the pulse oxemitry measures oxygenation the ETCO2 measures ventilation. Could ETCO2 monitoring be a tool in guiding the PACU nurse as she medicates by detecting hypoventilation and sedation?

Review of Research Literature

Cashman and Dolin(2004) did a medline research of 800 articles which 167 articles where chosen to determine effects of pain medication, such as respiratory depression and hypotension, given to patients after surgery. They were able to use the research to define what respiratory depression from analgesic use is: respiratory rate less than ten breaths per minute, PO% less than 90%, and Co2 level of 50 mm Hg. Fitzpatrick (2000) for his thesis designed a research project which compared the typical Etco2 monitor with nasal prong ETCO2 monitor. The conclusion showed that readings between the two kinds of devices showed positive correlation. This research will open the door to the newer hand held device which is non-invasive and can be used on non-intubated patient.

Sipkodd (2006) and D’Archy (2009) discuss research that shows using ETCO2 monitoring in conjunction with pulse oximetry provide increase patient safety in detecting increase hypoventilation and sedation when medicating with opioids. Both Core Curriculum for PeriAnesthesia Nursing (2004) and Core Curriculum for Critical Care Nursing2006) address potentials problems of pain management and sedation.

Aim of Project

The aim of this project is to find an ETCO2 monitor that can be used at bedside or in conjunction with current hemodynamic monitoring system in the PACU setting to detect hypoventilation and sedation to increase patient safety in pain management.

Outline of the Project

First, clear and through definition of problem will need to be explored and current practices in PACU need review? Next, research of the different ETCO2 devices available and discover accuracy, affordability and ease of use for bedside care. Thirdly, design simple three week study of using ETCO2 monitor in conjunction with PO in detecting hypoventilation and sedation and possibly comparing two or three different ETCO2 devices. Project and conclusion will be presented to Nursing Practice Council and Nursing Informatics 103 class.


Alspach, J. (2006). Core Curriculum for Critical Care Nursing. St. Louis: Saunders.

Cashman, J., & Dolan, S. (2004). Respiratory and hemodynamic effects of acute postoperative pain management: evidence from published data. British Journal of Anaesthesia , 212-223.

D'Archy, Y. (March/April 2009). Tip your cap to capnography. Nursing made incrediably easy , 5-6.

Fitzpatrick, L. (2001). Correlation between end-tidal carbon dioxide measured by capnoxygen mask and nasal cannula. Uniformed Services University of the Health Sciences.

Fu, E., Downs, J., Miguel, R., Schweiger, J., & Smith, R. (2003). Supplemental oxygen impairs detection of hypoventilation by pluse oximetry. Chest , 1552-8.

Quinn, D., & L., S. (2004). Perianesthesia Nursing Core Curriculum. St. Louis: Saunders.

Spikoff, M. (2006, July 24). Adding O2 and Co2 moitoring to PCA improves patient safety. Drug Source , p. 14.

No comments:

Post a Comment