Almost everything exists on a continuum. Pain management is no different.
The idea of completely good, or completely bad, pain management may not even be appropriate in describing the extremes, because clear distinctions are imaginary.
Anesthesia exists along a continuum. For some medications there is no bright line that distinguishes when their pharmacological properties bring about the physiologic transition from the analgesic to the anesthetic effects. Furthermore, each individual patient may respond differently to different types of medications.
The definitions of sedation/analgesia as Moderate or Deep provide excellent examples.
Moderate sedation/analgesia: (“Conscious Sedation”): a drug-induced depression of consciousness during which patients respond purposefully to verbal commands, either alone or accompanied by light tactile stimulation. No interventions are required to maintain a patent airway, and spontaneous ventilation is adequate. Cardiovascular function is usually maintained. CMS, consistent with ASA guidelines, does not define moderate or conscious sedation as anesthesia (71 FR 68690-1).
Deep sedation/analgesia: a drug-induced depression of consciousness during which patients cannot be easily aroused but respond purposefully following repeated or painful stimulation. The ability to independently maintain ventilatory function may be impaired. Patients may require assistance in maintaining a patent airway, and spontaneous ventilation may be inadequate. Cardiovascular function is usually maintained. Because of the potential for the inadvertent progression to general anesthesia in certain procedures, it is necessary that the administration of deep sedation/analgesia be delivered or supervised by a practitioner as specified in 42 CFR 482.52(a).
Respond purposefully is in the description of both. Respond purposefully should also be in the description of minimal sedation/analgesia and the description of no sedation/analgesia. The difference is the amount of stimulus required – following repeated or painful stimulus vs. to verbal commands, either alone or accompanied by light tactile stimulation. This is the primary difference.
Patients may require assistance in maintaining a patent airway,
Does that mean that a patient who does not require assistance in maintaining a patent airway is not receiving Deep sedation/analgesia?
and spontaneous ventilation may be inadequate.
Does that mean that a patient with adequate spontaneous ventilation is not receiving Deep sedation/analgesia?
What if supplemental oxygen is provided in anticipation of the potential for hypoxia, but the patient never becomes hypoxic?
What if supplemental oxygen is provided in response to hypoxia, the hypoxia resolves and does not return, but no ventilatory assistance is provided?
Should the following be added to the moderate sedation/analgesia definition?
Because of the potential for the inadvertent progression to deep sedation/analgesia in certain procedures, . . . .
If that is true, then what about adding the following to the definition of minimal sedation?
Because of the potential for the inadvertent progression to moderate sedation/analgesia in certain procedures, . . . .
Only no sedation/analgesia does not qualify for this kind of warning, but my point is not to provide a slippery slope justification for unethically withholding sedation/analgesia.
I am pointing out what a continuum means.
All of this raises the question, What is too much?
We cannot really consider that question without also raising the question, What is not enough?
How do we differentiate among the various possibilities of sedation/analgesia?
We differentiate according to the response of the patient, not so much according to whether the patient responds to verbal, painful, or repeated stimuli, but by the response to the question, Do you want more pain/sedation medicine?
One determines how we respond to potential ventilation needs of the patient, while the other determines how we respond to the sedation/analgesia needs of the patient.
What is too much?
That seems to depend on where the patient is on the sedation/analgesia continuum as determined by someone other than the patient.
What is not enough?
That seems to depend on where the patient is on the sedation/analgesia continuum as determined by the patient.
We cannot ask one question without implying the other question, so why do we address them in isolation so often?
 Revised appendix A, interpretive guidelines for hospitals— state operations manual, anesthesia services.
Centers for Medicare & Medicaid Services (CMS).
Effective December 2, 2011.
Free Full Text Download in PDF Format from CMS.