Misc. Pain Topics

Question 1

What is Allodynia?

Answer 1

Pain due to a stimulus that does not normally produce pain

Question 2

What is an example of Allodynia?

Answer 2

Fibromyalgia

Question 3

What is Alogenic?

Answer 3

A stimulus that is normally expected to produce pain

Question 4

What is an example of allogenic pain?

Answer 4

Surgical incision

Question 5

What is analgesia?

Answer 5

No pain is sensed in response to a stimulus that produces pain

Question 6

What is an example of analgesia?

Answer 6

Opioid analgesics relieve pain caused by ICH

Question 7

What is dysesthesia?

Answer 7

An abnormal and unpleasant sense of touch

Question 8

What is an example of Dysesthesia?

Answer 8

Burning sensation from diabetic neuropathy

Question 9

What is hyperalgesia?

Answer 9

Exaggerated pain response to a painful stimulus

Question 10

What is an example of hyperalgesia?

Answer 10

Opioid induced hyperalgesia from burn pain from opioids

Question 11

What is neuralgia?

Answer 11

Neuralgia is pain localized to a dermatome

Question 12

What is an example of neuralgia?

Answer 12

Herpes Zoster (shingles)

Question 13

What is neuropathy?

Answer 13

Impaired nerve function

Question 14

What is an example of neuropathy?

Answer 14

Silent myocardial ischemia from diabetic neuropathy

Question 15

What is paresthesias?

Answer 15

Abnormal sensation described as pins and needles

Question 16

What is an example of paresthesias?

Answer 16

Nerve stimulation during regional anesthesia

Numbness and tingling from a stroke

Question 17

Describe complex regional pain syndrome.

Answer 17

Complex Regional Pain Syndrome is characterized by neuropathic pain with autonomic involvement.

Risk factors include:
- Female Gender
- Previous Trauma
- Previous Surgery

Type 1 (Reflex Sympathetic Dystrophy)
Type 2 (Causalgia)

The key distinction is that type 2 is always preceded by nerve injury but type one is not.

Question 18

What are some treatment modalities for chronic regional pain syndrome?

Answer 18

Ketamine infusion
Memantine (another NMDA antagonist)
Gabapentin
Regional sympathetic block
Physical therapy
Steroids
Amitriptyline

Question 19

What are some drugs used to treat chronic pain?

Answer 19

Answer: Tricyclic antidepressants, SSRI, SNRI

Tricyclic antidepressants: Amitriptyline, Nortriptyline, Imipramine

SNRI: Venalfaxine, Duloxetine, milnacipran

SSRI: Fluoxetine, Citalopram

Question 20

What can the combination of SNRI and SSRIs cause?

Answer 20

Answer: Serotonin Syndrome

Serotonin syndrome is a potentially life-threatening drug-induced toxidrome associated with increased serotonergic activity in both the PNS and CNS.

It is characterized by dose-relavent spectrum of:
- free serotonin

S/sx of Serotonin syndrome include:

Question 21

Describe a thoracic paravertebral block

Answer 21

Answer: LA is infected into the paravertebral space (a potential space) targets the ventral ramus of the spinal nerve as it exits the vertebral foramen

Creates a unilateral sensory and sympathetic block along that specific dermatome.

Think of the paravertebral block as a single shot, unilateral epidural block.

You have to perform one block t each dermatome to be anesthetized

Question 22

When are the best times to utilize a thoracic paravertebral block?

Answer 22

Breast surgery, Thoracotomy and Rib Fracture

Question 23

What is the celiac plexus block utilized for?

Answer 23

Answer: Useful for management of cancer pain of the upper abdominal organs

Some examples include the:
- Distal esophagus
- Stomach
- Liver
- Pancreas
- Small intestine
- Colon (except the descending colon)

Question 24

What are some examples of complications with the celiac plexus block?

Answer 24

Orthostatic Hypotension
Retroperitoneal hematoma
Hematuria
DIarrhea
AAA dissection
Back pain
Retrograde migration of the inject ate (problem if a neurolytic is used)

Question 25

What is the superior hypogastric plexus block useful for?

Answer 25

Answer: the block is useful for the management of cancer pain of the pelvic organs

Examples include: uterus, ovaries, prostate and descending colon

Question 26

What are some complications that can be associated with the superior hypogastric plexus block?

Answer 26

A complication of the superior hypogastric plexus block include retrograde migration of the inject ate (a problem if a neurolytic is used)

Question 27

What is a sphenopalatine block useful for?

Answer 27

Answer: A sphenopalatine block can be used to relieve postural puncture headaches.

Question 28

What is a retrobulbar block?

Answer 28

Answer: The optic nerve is unique because it is the only cranial nerve that is part of the central nervous system (it’s enveloped by the meningeal sheath and bathed in CSF).

because of this, a LA is injected into the optic sheath is permitted direct entry to the brain

It is like giving a subarachnoid block in the optic sheath

Question 29

How does the LA work in a retrobulbar block?

Answer 29

LA is injected into the optic sheath can migrate towards the optic chasm where it anesthetizes CN2 and 3 on the opposite side of the block. This results in contralateral amaurosis (blondness)

LA that reaches the brainstem can cause APNEA (post-retrobulbar block apnea syndrome).

This complication typically becomes evident 2-5 minutes after injection. Spontaneous ventilation usually resumes in 15-20 minutes, but a full recovery may require up to an hour

Question 30

What is it important to assess in the retrobulbar block before performing?

Answer 30

Answer: the contralateral pupil before performing a retrobulbar block. If the pupil starts small but dilates shortly after the block, you should anticipate the development of post-retrobulbar block apnea syndrome

** BE READY TO PROVIDE CARDIOPULMONARY SUPPORT UNTIL LA IS CLEARED FROM CSF ***