**2. Optimal pain management**

International Association for the study of pain (IASP) has revised, 1979 definition of pain in 2020 considering concepts, challenges and compromises and stated "An unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage" and is relevant for pain management [8].

Pain perception and expression is associated with molecular biology which includes transmission of signals from an injury, transmitting through spinothalamic tract to thalamus in the brain, in nanoseconds, the signals move to limbic system. Alteration in the limbic system, changes in neurotransmitters, tissue receptors lead to high expression of pain, anxiety, frustration, and major depression.

#### **2.1 Acute pain**

*Pain Management - Practices, Novel Therapies and Bioactives*

(**Figure 1**).

before treatment plan [2].

World Health Organization (WHO) present definition comprises: "Palliative care is an approach that improves the quality of life of patients and their families facing the problem associated with life-threatening illness, through the prevention and relief of suffering by means of early identification and impeccable assessment and treatment of pain and other problems, physical, psychosocial and spiritual." More recently "Palliative Approach, Palliative Care and End of Life Care" has been accepted internationally as well as also "Early, Integrated, Collaborative and Inter-professional Care". Advanced care planning, goals of care, and good communication with relevant language and words reduce distress of patient and family

Now palliative care has patients with palliative approach, palliative care, end of life care and survivorship with cancer or organ failure. Dr. Pippa Hawley explained the value of a visual "Bow Tie Model" as a disease management and palliative care

The Gold Standards Framework from the UK has prognostic indicators; general, cancer, and organ failure trajectories, which are important and useful to consider,

triangles can be adopted for cancer and non-cancer interventions [1].

were limited in Canada and other parts of the world.

were minor and could be better in Canada [3].

*supportive care or some individuals can be at the end of life.*

At the end of last century, pain management and scientific research had improved but chronic pain and palliative care specialists with present knowledge

In 2007, Boulanger et al., did a study whether chronic non-cancer pain has improved, though more patients were receiving medical analgesics, the changes

Genetics play a major role with physical, psychological health or illness and our knowledge and management is improving [4, 5]. Nutrition has a role in pain management and requires learning care providers, patients, and families [6]. Optimal pain management requires history, physical examination, investigations, and appropriate interventions. In the past four to five years "opioid crisis" increased deaths due to the use of illicit fentanyl [7]. "Pain crisis" is an experience of a patient relating to pain and requires immediate interventions, whereas "opioid crisis" relates to substance use disorder or an error with medication or illicit drug use. IASP, pain and palliative care societies across the world are encouraging physi-

cians and interprofessional team members to consider interventions for pain management, clinical research and in the past three decades, several peer reviewed manuscripts have been published for pain management with such evidence and knowledge, can reduce pain in an individual and community can prosper.

*Bow Tie Model: Bow Tie Model: Palliative care is an interdisciplinary coordination at the time of diagnosis and the timelines can vary in an individual head towards survivorship with cure or illness is controlled and requires* 

**4**

**Figure 1.**

Acute pain like "stubbed toe or a needlestick" disappears in a few minutes secondary to the antinociceptive nervous system triggered and the pain stimuli release endorphins within the brain, and enkephalins in the brain stem, which block the transmission of pain signals at different levels and the ion channels are functioning.

However, the acute pain secondary to cell injury caused by pressure, heat, chemicals, or physical stimulus; damaged cells release lysosomes which causes inflammation within hours and magnifies the pain signals through the release of signaling chemicals such as prostaglandins, arachidonic acid and leukotrienes in the nervous system and involves glutamate at low levels. Ion channels may not function appropriately thus endorphins may not be active [9].

Acute nerve injury associated with acute neuropathic pain, e.g., broken bone, amputation.

#### **2.2 Chronic pain**

Acute, nociceptive, and inflammatory pain can transition to chronic pain, if the pain persists more than 3 months in an individual. In this period of transition, the ion channel function may not be normal, and endorphins may not be active.

Following an acute injury; infection, crush or nerve injury, degeneration of tissues, micro, macro vascular insufficiency, and cancer the recovery is low, and healing is slower, leading to chronic pain associated with poor quality of life.

Palliative and end of life care, some patients who are dependent, frail and require extensive nursing care may have pain crisis along with delirium. Identifying the difference between the symptoms, pain and delirium, using appropriate pharmacological interventions are useful. Refractory symptoms like delirium, respiratory distress, seizures may need palliative sedation. Patients with pain and agitation may require analgesic and intermittent or palliative sedation [10].

#### **2.3 Cancer and pain**

Advanced cancer trajectory leads to end of life, pain crisis or delirium and other co-morbidities need to be considered. However, if patient responds to intervention, almost 50% of them are in survivorship and not end of life, requiring long-term pain and symptom management. Cancer pain is often a "mixed pain" as inflammation around primary or metastasis is common [11].

#### *Pain Management - Practices, Novel Therapies and Bioactives*

**Figure 2.** *Pain classification: acute, chronic, and acute on chronic pain.*
