Assessing Pain in Mechanically Ventilated Patients

Pain Management


On January 1, 2001, pain management standards went into effect for Joint Commission accredited ambulatory care facilities, behavioral health care organizations, critical access hospitals, home care providers, hospitals, office-based surgery practices, and long term care providers. The pain management standards address the assessment and management of pain. The standards require organizations to:


-Recognize the right of patients to appropriate assessment and management of pain
-Screen patients for pain during their initial assessment and, when clinically required, during ongoing, periodic re-assessments
-Educate patients suffering from pain and their families about pain management


Assessment of Pain


The National Pharmaceutical Council and Joint Commission on Accreditation of Healthcare Organizations (JCAHO) recommends that an assessment of pain includes the following:


Patient history that includes:
-Qualities of the pain, such as intensity, duration, location, and exacerbating or alleviating factors
-Past and present strategies for pain management and their outcomes
-Medical problems—past and present—that could influence care
-Family history
-Psychological or psychosocial factors that could influence treatment
-Effect of pain on daily living
-The patient’s (and family’s) expectations for pain management
-Physical examination to find source of pain and to reassure patient that pain is being taken seriously
-Diagnostic tests to supplement, but not replace, the patient’s assessment
-Patient should be instructed to report any change in pain so that reassessment can occur


Barriers to Pain Assessment


Mechanically ventilated patients are often unable to report and describe pain as easily as a non-intubated patient. Their ability to self report may be hampered by delirium, cognitive and communication limitations level of consciousness, presence of an endotracheal tube, sedatives, and neuromuscular blocking agents.


The Thunder Project II, sponsored by the American Association of Critical Care Nurses, in a study of over 6,000 patients, ages 4 to 97, revealed that even simple procedures in the ICU were associated with various levels of pain.  These procedures include turning, wound drain removal, femoral catheter removal, central line placement, and non-burn, wound dressing changes.  Mechanically ventilated patients often try to communicate pain to their nurses.  Some techniques used to report pain in the mechanically-ventilated include grabbing the nurse’s arm, signaling with their eyes, and moving their legs up and down (Puntillo, 1990).  Some conscious, intubated patients can self-report and provide some information regarding their pain.  This self-report is the most accurate indicator of pain and should be taken seriously.  Other indicators should also be considered when providing pain relief include (in order) pathologic conditions or procedures that usually cause pain, behaviors (i.e. facial expressions, body movements, crying), reports from family members, and lastly physiologic measures such as blood pressure and respiratory rate.

For mechanically ventilated patients, it is important to remember that neither sedatives (propofol, benzodiazepines) nor paralyzing agents (cisatracurium, rocuronium) provide pain control. Most patients on sedation will require adjunctive use of an opioid to maintain comfort while intubated.  Opioid use in neuromuscular blockade is highly recommended for every patient due to inability to express physical reactions to pain.

There are pain assessment tools available such as the FLACC pain scale, COMFORT behavioral scale, Behavioral Pain Scale, and the Critical Care Pain Observation Tool.

Before use of a pain assessment tool:

-Obtaining a self report from the patient. Obtaining a self-report should be attempted- this is the most accurate form of pain assessment. Because barriers to self reporting, such as level of consciousness can wax and wane and impact ability to self-report, serial assessment for the ability to self-report should be conducted

-Assess Potential Causes of Pain/Discomfort. Sources of pain in critically ill patients include the existing medical condition, traumatic injuries, surgical/medical procedures, invasive instrumentation, blood draws, and other routine care such as suctioning, turning, positioning, drain and catheter removal, and wound care . Verbal adult patients describe a constant baseline aching pain with intermittent procedure-related pain descriptors such as sharp, stinging, stabbing, shooting, and awful pain; thus it should be assumed that those unable to report pain also experience these sensations. In addition, immobility, hidden infection, and early decubiti can cause pain and discomfort.

- Observe Patient Behavior. Facial tension and expressions such as grimacing, frowning, and wincing are often seen in critically ill patients experiencing pain. Physical movement, immobility, and increased muscle tone may indicate the presence of pain. Tearing and diaphoresis in the sedated paralyzed and ventilated patient represents autonomic responses to discomfort. Behavioral pain scales are not appropriate for pharmacologically paralyzed infants, children, adults, or those who are flaccid and cannot respond behaviorally to pain. Assume pain is present and administer analgesics appropriately to patients who are given muscle relaxants and/or deep sedation and experience conditions and procedures thought to be painful. Patients may exhibit distress behaviors as a result of the fear and anxiety associated with being in the intensive care unit. An analgesic trial or surrogate reporting may be helpful in distinguishing distress behaviors from pain behaviors.

Analgesic Trial

To perform an analgesic trial, an analgesic is given and time is allowed for it to take effect.  The patient's behavior is observed to see if there is a change in a perceived pain expressing behavior (teeth grinding, restlessness, etc.).  If behaviors improve- pain should be assumed to be the cause and the analgesic should be continued as needed in addition to non-pharmacologic interventions.

Surrogate Reporting
Parents of children, caregivers, and family members can help identify specific pain indicators for critically ill individuals. A family member's repot of their impression of a patient's pain and response to an intervention should be included as one aspect of a pain assessment in the critically ill patient.

Vital Sign Changes

Relying on changes in vital signs as a primary indicator of pain can be misleading because these may also be attributed to underlying physiologic conditions, homeostatic changes, and medications. There is limited evidence that supports the use of vital signs as a single indicator of pain; however, both physiologic and behavioral responses often increase temporarily with a sudden onset of pain.  Changes in physiologic measures should be considered a cue to begin further assessment for pain or other stressors. Absence of increased vital signs does not indicate absence of pain.

Pain Assessment Tools

FLACC Pain Assessment Tool

The acronym FLACC stands for face, legs, activity, cry and consolability.  These five categories are assessed and scored appropriately according to observed behavior.  The lowest score is a 0, representing no pain and continues thorough 10, with higher scores correlating to a higher level of pain.  The FLACC pain scale is designed for patients ages 2-7 years old, and while it can be used to rate pain in ventilated patients, it is not appropriate for adults in rating components such as 'cry' and 'consolability'.  There is also very little data to support its use in adult patients.  The majority of the FLACC pain scale seems easily modifiable to assess pain in a ventilated pediatric patient, however, 'cry' may require an interpretation by the observer, since a patient is inaudible while on the ventilator.

COMFORT Behavioral Scale

The COMFORT behavioral scale scores eight characteristics from one to five, resulting in a score of eight to forty, with discomfort increasing with higher numerical value.  The patient's alertness, agitation, respiratory response, physical movements, blood pressure, heart rate, muscle tone, and facial expression are observed and points are awarded accordingly.  The scale is fairly comprehensive, as it addresses behavior as well as vital sign changes.  This scale was developed for children, but can be used for infants, children, and adults in the critical care or operative setting who are unable to self report.

Behavioral Pain Scale (BPS)
The Behavioral Pain Scale or BPS uses four categories that are each rated 0-2 based on observation.  A score of zero indicates no pain, with higher numbers indicating a higher level of pain.  The BPS is applicable to intubated, sedated patients of any age.

Critical Care Pain Observation Tool
The Critical Care Pain Observation Tool or CPOT

has four components: facial expression, body movements, muscle tension, and compliance with the ventilator for intubated patients or vocalization for extubated patients. Each of these behaviors is assigned a rating of 0 to 2, with 0 representing no pain and discomfort increasing with higher numerical values.  In studies, the CPOT has shown validity through significant associations between patient self reports of pain and CPOT pain ratings.  The Critical Care Pain Observation tool is valid for any mechanically ventilated patient.

About this Education Tool:
This blog is intended to educate health care providers about the importance of an accurate pain assessment in mechanically ventilated patients and to provide different pain scales for the assessment of pain.  It may also be accessed by families and friends of patients that are mechanically ventilated, to help explain what health care providers are observing to assess whether their loved one is uncomfortable or in pain.  Using a blog as an educational tool is advantageous because it can be accessed by anyone who has access to the internet.  A blog is also a public forum where users can post comments or questions.  The only disadvantages to using a blog are that a user has to have access to a computer with internet, and not everyone is comfortable and fluent in blogging.


Resources (using 6th ed. APA)

Herr, K., Coyne, P., Key, T., Merkel, S., Pelosi-Kelly, J., and Wild, L. (2006). Pain assessment in nonverbal patients: Clinical recommendations: Intubated and/or unconscious persons: Guiding principles for the assessment of pain. American Society of Pain Management Nursing, 7(2), 44-52.

The Joint Commision (2011). Facts about Pain Management.  Retrived June 30, 2011 from http://www.jointcommission.org/pain_management/

Kabes, A., Graves, J., and Norris, J. (2009). Further validation of the nonverbal pain scale in intensive care patients. Critical Care Nurse, 29(1), 59-66.

doi: 10.4037/ccn2009992

National Institutes of Health (2007). NIH Pain Consortium: Pain Scales. Retrieved July 2, 2011 from http://painconsortium.nih.gov/pain_scales/index.html

Sessler, C. N., Grap. M., and Ramsay M. (2008). Evaluating and monitoring analgesia and sedation in the intensive care unit. Critical Care, 12, 112-117.

doi:10.1186/cc6148

Voepel-Lewis, T., Zanotti, J., Dammeyer, J.A., and Merkel, S. (2010). Reliability and validity of the face, legs, activity, cry, consolability behavioral tool in assessing acute pain in critically ill patients. American Journal of Critical Care, 19(1), 55-61.