Page 291 Guide to Pain Management in Low-Resource Settings

Breakthrough Pain, the Pain Emergency, and Incident Pain 279

• Temporary fl ares of severe or excruciating pain in (described as aching, dull, and drilling) is opioids.
the previous 24 hours Depending on the intensity of pain, the route of ap-
plication is chosen. In “excruciating” pain (NRS score
How is breakthrough pain assessed? of 9–10), the time interval between an oral opioid and
pain reduction would be considered to be too long (usu-
Currently, there is no validated assessment tool for ally 30 to 45 minutes) and intravenous (i.v.) titration of
breakthrough pain, but the assessment of breakthrough an opioid would be indicated (usually 5–10 minutes). In
pain should involve: moderate to high pain (NRS score of 6–8), oral opioids
• Taking a pain history may be used. All immediate-release opioids are suitable
• Examining the painful area as i.v. or oral breakthrough pain medications.
• Appropriate investigations. It is a good idea to combine opioids with nono-
• Assessment of pain intensity with well-known pioid analgesics such as metamizol, ibuprofen, or diclof-
tools: e.g., verbal rating scale or numerical or vi- enac, if the patient is not already taking them regularly.
sual analogue scale)
Practical questions about
How can breakthrough pain breakthrough pain
be managed?
I am afraid of respiratory depression. Is
As always, the best strategy for treatment of break- worrying about this typical opioid side
through pain would seem to be treatment of the cause eff ect justifi ed?
of the pain, but unfortunately, most of the time, a Pain is an antagonist for all depressing eff ects of opi-
cause of pain that could be eliminated immediately is oids. As long as the pain and the opioid dose are bal-
not apparent. anced, there will be only tolerable sedation and no
Breakthrough pain is a heterogeneous condi- respiratory depression. Since the principle of break-
tion, and its management therefore may involve the through pain management is opioid titration, this bal-
use of a variety of treatments, rather than the use of ance between pain intensity and opioid side eff ects
a single, standard treatment. Th e most appropriate can be found easily. Th e goal of titration is not no pain
treatment(s) will be determined by a number of dif- (NRS score of 0), as at the doses required, side eff ects
ferent factors, including the etiology of the pain (e.g., would prevail, but a tolerable pain level (NRS score of
cancer-related, non-cancer-related), the pathophysi- 3–4). Th en respiratory depression should not be a ma-
ology of the pain (e.g., nociceptive, neuropathic), the jor concern. However, in rare instances, pain intensity
characteristics of the pain (e.g., episode duration), the may not change, but the patient may become more and
characteristics of the patient (e.g., performance sta- more sedated. In these extreme situations, the patient
tus), the acceptability of diff erent interventions, the must be woken up to be able to tell you that the pain is
availability of diff erent interventions, and the expense still excruciating.
of diff erent interventions.
First, you should evaluate whether break- How can a patient be heavily sedated,
through pain may be lessened by nonpharmacological but still in excruciating pain?
methods, such as repositioning or bed rest, rubbing or Th e explanation is that a patient can have pain that is
massage, application of heat or cold, and distraction and not “opioid sensitive,” meaning that because of the type
relaxation techniques. Also, never forget to check the of pain (e.g., neuropathic pain) or tolerance eff ects (rap-
fullness of the bladder in cases of acute pain exacerba- id dose escalation with opioids prior to breakthrough
tion in the lower abdominal region, especially in non- pain), the opioids are not working. Th erefore, the pa-
communicating or sedated patients. tient is only experiencing the side eff ects of the opioids.
Unfortunately, there is relatively little evidence Alternative techniques to relieve the pain have
to support the use of these interventions in the treat- to be considered. In neuropathic pain, oral carbam-
ment of breakthrough pain episodes. azepine or oral/i.v. phenytoin might work, otherwise
Second, if pharmacological intervention is es- i.v. ketamine or S-ketamine in analgesic doses might
sential, the drug class of choice in nociceptive pain be indicated (0.2–0.4 mg/kg or 0.05–0.2 mg/kg body