The evaluation of pain is extremely difficult due to its subjective nature. We need to move to an evaluation of acute pain that not only takes the patient’s perception into account, but also, for the first time, incorporates objective measures of pain into a global assessment matrix.
When a patient is in pain, either from an injury or surgical procedure, the pertinent question should be, “is the pain tolerable?” Each of us has a threshold at which point the addition of an analgesic should be considered to prevent the consequences of untreated acute pain.
Hot topic: The opiod pain paradox
This threshold should not be based on an arbitrary numerical value, but whether the pain is tolerable for that individual. Once the patient states that their pain is intolerable, we then attempt to correlate this subjective feeling with the following objective measures prior to the initiation, maintenance and escalation or de-escalation of analgesic treatment.
Here is a mnemonic to aid in remembering the objective measures of acute pain:
Opioids Rarely Help Bodily Pain
· Observation—Is the patient grimacing, screaming, diaphoretic, combative, crying, sleeping, drowsy, etc.? This observation must be made after confirming that the physical/verbal symptoms are not due to delirium, hypoxemia, hypercarbia, acidosis or other metabolic issues that may be confused with the outward appearance of discomfort. Once it is established that the physical signs are due to pain, you can proceed with analgesic treatment. If, however, you have not established that your observation is from pain, or if the patient appears drowsy, somnolent or obtunded, do not give analgesics.
· Respiratory Rate—In my opinion, respiratory rate in the presence of a patient stating that their pain is intolerable is the most important indicator and guide for analgesic therapy. A normal respiratory range is between 12-20 breaths per minute. These are actual breaths associated with ventilation of a normal tidal volume. They are not attempted, shallow or obstructed respirations. Once it is confirmed that there are no abnormal neurologic, metabolic or psychological issues involved, the respiratory rate may now be assessed. A true respiratory rate greater than 20 with a patient stating intolerable pain is a good indication for analgesic treatment. If, however, the respiratory rate is less than 12, I would not initiate or escalate opioid analgesic therapy.