Evaluate pain management modalities in the acutely injured patient.
Review the pharmacology of acetaminophen (paracetamol), nonsteroidal anti-inflammatory drugs, opioids, tramadol, local anesthetics, and ketamine in trauma patients.
Discuss the role of antidepressants, anticonvulsants, benzodiazepines, alpha 2 agonists, and entonox for acute pain in trauma.
Discuss the role of multimodal analgesia for trauma patients.
The widely accepted definition of pain was developed by a taxonomy task force of the International Association for the Study of Pain: “Pain is an unpleasant sensory and emotional experience that is associated with actual or potential tissue damage or described in such terms” . Managing pain can be challenging in most scenarios and providing adequate pain relief forms a vital part in the initial management of trauma. Inadequate analgesia in acute situations can have deleterious effects on the immune system, healing process, and autonomic activity and can lead to the development of a chronic pain state (see Chapter 35).
PATHOPHYSIOLOGY OF STRESS RESPONSE TO INJURY AND PAIN
Pain is a protective response. This reflex response has an effect on multiple systems in the body. These include exaggerated stress response, sleep deprivation, altered glucose homeostasis, increased sympathetic nervous system activation, and altered gastrointestinal, renal, and endocrine function. The stress response produced has effects on various organ systems additionally such as cardiovascular, immune, endocrine, and respiratory systems. Thus, the stress response to injury is a complex hormonal and neurologic phenomenon. In a trauma patient, the consequences of this response are multifactorial.