True compassion means not only feeling another's pain but also being moved to help relieve it...(Daniel Goleman)

Wednesday, February 13, 2019

Overview of a Pain Clinic


 Chronic pain is often defined as a pain that lasts for more than 3 months. It is often considered a disease of the brain. Patients of chronic pain present with a constellation of signs and symptoms with often and ill-defined pathophysiology. It usually consists of a heterogeneous group of patient population suffering from various kind of central nervous system disorder. The disease may lead to a complex presentation involving sensory, emotional, cognitive, modulatory and autonomic changes.

Managing such a patient and pain clinic requires an overall care of the patient’s constant pain in question, focusing on successful control of pain (acute on chronic and chronic) along with consideration of the distressful symptoms of the disease, prevention of side effects and therapeutic modalities while keeping the patient comfortable.

Pain management is thus an interdisciplinary subject requiring health care members working as a team. Each member contributes a unique blend of knowledge and clinical practice in the care of patient. Effective pain control results in decreased morbidity and mortality as well as an improved patient satisfaction with healthcare.

Apart from the disease process itself that initiated the pain, chronic pain is influenced by a combination of genetics, stress, behavioural, cultural and emotional factors. A persistent pain of long duration can cause changes in the nervous system thus making the pain a distinct chronic disease by itself. It can then lead to certain other symptoms like depression, anxiety as well as decreased physical activity.

Management of a chronic pain patient should start at Primary health care level. Primary health care forms the first point of contact of an individual with the healthcare system. The need of the hour is to train the staff, to make them better educated in understanding pain and its various causes and to collaborate with pain specialists in case of persistence of pain despite treatment.

Setting up a pain clinic
Bonica has been credited with the development of modern multidisciplinary pain clinic. He was an anaesthetist working at an army Hospital in the USA following World War II and is considered as father of modern pain management. He observed that patients with causalgia responded well to nerve blocks whereas, others with more chronic pain problems did not. Bonica discussed about his patients with other specialists in related fields to arrive at a diagnosis and a treatment plan was charted out thus, making his efforts a multidisciplinary approach which was later found to be more effective and efficient.

Pain clinic
Pain clinic is usually an OPD based service where patients with pain who are not incapacitated and do not need continuous assessment on a daily basis are seen. The basic aim here is to treat the patient’s pain and not the underlying disease. Therefore a thorough evaluation from various specialities is a prerequisite before referral to a pain clinic.

there are different types of pain clinics like single modalities clinic using ‘nerve block’; acupuncture; electrical nerve stimulation; physiotherapy’ counselling etc. In this case specialists from a single stream man the clinic.

Pain clinic can be syndrome oriented like ‘low back pain’ or ‘headache’ clinic.

Multidisciplinary pain clinics treat various pain syndromes when they present. They often have facility for keeping a patient admitted for a procedure. They play a more active role in patient management as compared to procedure based clinics.

A pain Clinic can function on its own or it may be a part of a larger Institution like a Medical College or a Hospital.

Members of the pain management team
Being an interdisciplinary subject professionals from various streams are part of the team which include anaesthesiologist, rheumatologist, physiatrist, orthopedician, neurologist, neurosurgeon and psychiatrist. The team should be headed by a team leader.
An anaesthesiologist is in a unique position to coordinate with other specialities. The ability and skill to interact with members of the team, expertise in the technical skill to administer sedation and pain relief propels him to be a leader. In practice the success of continuing the program is usually based on anaesthesiologist and psychiatrist whereas other medical specialists contribute as required.

Auditing
It is mandatory to audit the efficacy of the service frequently depending on the policy of the institution. It can be used as a tool for learning in addition to improving the quality of service.

Some chronic conditions presenting to the pain clinic
Non malignant
     Acute herpes zoster
     Post herpetic neuralgia
     CRPS 1 and 2
     Sympathetic mediated pain
     Diabetic neuropathy
     Phantom pain
     Vasomotor rhinitis
     Myofascial pain syndrome
     Fibromyalgia
     Low back pain
     Failed back syndrome
     Headache
     Lumbago
     Frozen shoulder
     Plantar fasciitis
     Urogenital pain
     Chronic pelvic pain
     Post-surgical pain

Malignant pain
     Cancer pain with or without bony secondaries
     Terminally ill cancer patients
     AIDS patient




Tuesday, January 17, 2017

Does the Moon affect Joint Pain?

I have been attending to some patients referred to me for pain management. Most of the patients who visit an Anesthesiologist at the OPD clinic for pain problems usually suffer from chronic pain; from Rheumatoid arthritis to Osteoarthritis and so on. 

With the advent of various medications, nerve blocks and therapies most of the pain intensity can be fairly controlled. However, a patient suffering from a chronic condition often has a complete to near complete pain-free period interspersed between periods of exacerbations when the pain intensity is beyond control of usual routine medications and require top up therapy. 

During one of my OPD attendees was a middle aged male of 40 years who had been living with seronegative Rheumatoid Arthritis over the past 5 years. He was on DMARDs (Methotrexate 15mg weekly and Sulfasalazine 1 gm daily) along with Folic Acid supplementation with which his disease was under fair control. 

However, he visited me on one occasion with an acute exacerbation of his condition and he rated his pain as an 8 out of 10. As an initial therapy NSAID and Paracetamol were prescribed which provided him adequate relief and he was at ease. But he returned to the clinic with another exacerbation after four weeks. While taking the clinical history, he mentioned that the moon brought on his pain. On further probing he revealed that he felt as if his pain was worse on near-full moon and full moon nights. He informed us that it had been like this over the last six months with an accuracy of +/-2 to 3 days when he considered the severity of his pain with the phase of the moon (Full moon night) 

His case was intriguing and so I decided to enquire other patients who presented with chronic pain of more than a year duration if they had also had a similar predicament. Surprisingly four out of fifteen patients had observed such an event. As the weeks passed with the passage of the next full moon another three patients also reported an exacerbation of their pain. However I decided not to consider these three cases as I had a feeling that discussion about the phase of moon and pain might have biased their opinion. 

Back from the chamber I enquired some of my fellow colleagues if they had similar cases but a mixed opinion arose out of the discussion. Some of them laughed it off while some justified it with the moon’s gravity. Internet research also gave a mixed opinion. While some felt that brighter nights led to less melatonin and hence more time needed to fall asleep coupled with more instances of break in the night time sleep that led to increased intensity of pain (1) but such claims on sleep quality was refuted by others (2). Some others postulated that the moon’s enhanced gravitational pull on full moon nights which led to synovial capsule stretching that led to enhanced sensation of pain from the damaged tissues because of the pull. The justification was that gravity was an important factor affecting the closed synovial cavity (3,4). 

In a large study (PAIN OUT) involving 10 international hospitals participating in the research project, 12,224 patient data sets were assessed where hospitalized patients were asked for their pain after surgery and pain treatment side effects using numerical ratings scales from 0 to 10. Kurskal–Wallis H-tests were applied to find out if the four moon phases had any significant outcome differences. The only items that show statistically significant differences were pain interference with sleep and drowsiness. The most effected sub-groups that showed statistically significant connections to lunar phases in some variables were men and elderly people (5). 

In a study from NASA where effect of microgravity on cartilage homeostasis was studied it was found that the combined effects of radiation and microgravity simulated exposed chondrocytes to undergo morphological rearrangement of the actin cytoskeleton. Gene expression analyses confirmed that cells exposed to both radiation and simulated microgravity express more collagen I and less collagen II and aggrecan, which is characteristic for de-differentiated chondrocytes (6).

Therefore, variability of opinion and research findings on the various aspects of the subject may be narrowed down by further research on the topic.


References:

x
1.
Cajochen C, Songül AE, Mirjam M, al e. Evidence that the Lunar Cycle Influences Human Sleep. Current Biology. 2013; 23(15): p. 1485–1488.
2.
Haba-Rubio J, Marques-Vidal P, Tobback N, al e. Bad sleep? Don't blame the moon! A population-based study. Sleep Med. 2015; 16(11): p. 1321-6.
3.
4.
Mcminn. Last's Anatomy: Regional and Applied. In.: Elsevier Australia; 2003. p. 542.
5.
Komann M, Weinman C, Meissner W. Howling at the moon? The effect of lunar phases on post-surgical pain outcome. Br J Pain. 2014; 8(2): p. 72–77.
6.
x



Tuesday, November 1, 2016

 long-glanded blue coral snake to provide next generation analgesic?


Long-glanded blue coral snake of southeast Asia also known as "killer of killers" can help to reduce a lot of human suffering. This visually striking snake with a vibrant blue body and a blood red head is a specialist feeder that preys on other fast moving, venomous snakes.

It has the world’s biggest venom glands which grow up to one quarter of its body length.The snake can grow up to two metres long and its venom glands can reach 60 centimetres. It has a fondness for eating young king cobra snakes and because it feeds on other venomous snakes which are capable of profound retaliation, it needs to be able to immobilise its prey almost instantly.

Therefore the long-glanded blue coral snake has developed venom which administers a lightning strike electrical spasm throughout the body. Like scorpions it causes its prey to completely spasm.

The study, published in the journal Toxin, reveals how it achieves such a feat. The venom of the blue coral snake contains a number of unusual peptides that switch on all of its victim’s nerves at once, causing it to become instantly paralysed.

So what does this have to do with human health?

According to Dr Fry (associated with the research), it works to act on a particular type of sodium channel that is important for the treatment of pain in humans. “Even if it doesn’t itself become a drug, which it still may, it already immediately teaches us about how those channels work which means we have more data for drug design,” he said.

However like plenty of other species, the long-glanded blue coral snake faces a tough and uncertain future. It’s an incredibly rare snake and it’s becoming only rarer. It is found in the monsoonal forest in southeast Asia which are being wiped out at an alarming rate.

So, conservation efforts are equally important in preserving such rare pieces of evolution which may hold the key towards elimination of human suffering and creation of a better tomorrow.

Wednesday, December 16, 2015

New Drug of Abuse: Gabapentin




Gabapentin is increasingly being used by patients in methadone maintenance programs to get a high.

Increasing availability, infrequent drug testing, and potentiation of euphoria when combined with opioids have likely all contributed to gabapentin misuse.

  • Drug Abuse Warning Network (DAWN) data show that ED visits involving thenonmedical use of gabapentin have increased by 90% in the United States since 2008. 
  • DAWN data also suggest that 20% of patients in treatment may misuse or abuse gabapentin.

Meanwhile, there has been a rise in gabapentin prescribing.

Current advice on prescribing Gabapentin: use caution. Don't necessarily avoid prescribing it, but be careful and prescribe it from visit to visit. Don't just give somebody six refills and say you will see them in 6 months. 


Tuesday, May 12, 2015

Pre-emptive analgesia

Ñ Pre-emptive analgesia is an antinociceptive treatment that prevents establishment of altered processing of afferent input, which amplifies postoperative pain.

Ñ Concept of preemptive analgesia was formulated by Crile

Ñ DEFINITION: Treatment  that:
ü  Starts before surgery
ü  Prevents the establishment of central sensitization by incisional injury ( covers period of surgery)
ü  Prevents establishment of central sensitization caused by incisional and inflammatory injury (covers the period of surgery and the initial postoperative period).

Ñ Strategies:
ü  Local skin infiltration-pre and post operative

ü  PCM and NSAIDS: reduces inflammation, pain , fever:
Ø  Diclofenac - used in orally, per-rectally,intramuscularly and continuous infusion.Single dose: 1.0 - 2.0 mg/kg; maximum dose; 3mg /kg /day. Interval: 6- 8 hours.
Ø  Paracetamol - can be administered in orally, infusion and per-rectally. Single dose: 10 - 15 mg/kg; maximum dose: 60mg/kg/day. Interval: 4- 6 hours.

ü  Intravenous  Opioids:
Sites of action:
Ø  Periaqueductal Grey (PAG), Limbic system
Ø  Caudal brain stem (nucleus raphe magus, magnocellular reticular formation)
Ø  Spinal cord
Mechanism of action:
Ø  inhibition of neuronal activity
Ø  inhibit the release of neurotransmitters
Ø  activate descending inhibitory systems

ü  Epidural anaesthesia, Nerve blocks: Commonly practiced agents are Bupivacaine and Lidocaine with or without Epinephrine (1:200,000 or 5 ug/ml).

ü  Both agents can be given local infiltration, intrathecal, caudal or epidural and peripheral nerve block (llioinguinal and iliohypogastric nerve block, penile nerve block, intercostal nerve block, brachial plexus block etc.).

ü  Alpha 2 agonists:
Ø  play a key part in the descending modulation of pain.
Ø  Descending supraspinal pathways include the periaqueductal gray area of the midbrain, stimulation of which results in widespread analgesia.
Ø  In particular, stimulation of alpha-2 receptors located in the locus ceruleus and parabrachial nucleus of the medulla affords analgesia through G-protein mediated potassium channel conductance

ü  NMDA  receptor antagonists:
Ø  Magnesium, Ketamine : Combinations of ketamine and magnesium potentiate each other.Combinations are more effective analgesics than either alone; Superadditive (>90%) effect of coadministration allows for reduced doses of each; thus, less side effects. 
ü  Others:
Ø   Dextromethorphan, Methadone
Ø   Tricyclic antidepressants, Nicotine agonists

ü  repeated episodes of constant noxious input primes NMDA receptors for chronic pain state (central sensitization)