Relieving post-traumatic pain

Admission

Damage to the body as a result of an active injury is one of the most serious challenges of modern medicine. Injuries are the third most frequent (after cardiovascular diseases and cancers) cause of death and 2. the cause of incapacity to work. The injury rate in New Zealand is 660 per 100,000 inhabitants. These data concern patients with significant injuries, that is, those who require medical attention. It should be emphasized that 50% of these patients are hospitalized. This means that about 250,000 people suffer serious injuries in our country during the year, and 120,000 accident victims require hospital treatment.

The effectiveness of medical teams at the scene of the accident increased significantly, which contributed to the improvement of survivors (during the Vietnam War, the mortality accompanying war injuries was 24%, and during Iraq only 10%), and to an increase in patients with extensive injuries usually associated with severe pain requiring complex therapeutic management. Most injuries affect the skin, subcutaneous tissue, joints, bones and other well-ventilated tissues. Therefore, more than 80% of affected people experience acute, severe pain with varying durations.

Pain is an inevitable consequence of injury, and its intensity depends not only on the extent and severity of the injury, but also on its location. Therefore, extensive abrasions of the epidermis or contusions of the soft tissues of the torso may be the cause of less severe pain than the insulated injury of the abdomen, eye or internal organs.

The biological function of acute pain is associated with its warning-protective effect, while in the case of injuries involving somatic structures (wounds, sprains, fractures), acute pain enforces limitation of activity, which together with the accompanying hypersensitivity reduces the potential risk of further damage or exacerbation of pathophysiological changes.

Acute pain associated with injury initiates a segmental and supra segmental response of the central nervous system (CNS), which helps the body maintain homeostasis during the pathological process. These reactions relate mainly to changes in the circulation (acceleration of the heart rhythm, increased cardiac output, increased blood flow in the brain and muscles) and breathing (acceleration and deepening of breaths). They are referred to as atavistic, and their aim is to adapt the system to “fight or flight” activities. However, the prolongation of these changes over time, as well as the fact that acute pain is one of the important factors generating the system response to injury, make it – despite the beneficial effect of pain stimulation at the initial stage of the pathological process – its persistence (lack of effective pain relief) it is the cause of many complications.

However, it should be emphasized that about 30% of the population does not feel pain for minutes or even hours immediately after the injury. This phenomenon is called stress-induced analgesia and is the result of activation of endogenous antinociceptive systems (including opioid, noradrenergic, cholinergic, serotoninergic, and GABAergic), inter alia as a result of particularly intense emotional factors. In the vast majority of cases, proper pain management and the process of natural healing make the acute pain usually disappear after a few or a dozen or so days. However, in the absence of or ineffective analgesic therapy, the persistent acute pain causes the growth of pathophysiological changes in the CNS (neuroplasticity) and the acute form of pain can transform into a chronic (persistent) syndrome of pain. Therefore, regardless of the humanitarian condition of relieving acute pain, proper analgesia is also necessary to inhibit the development of the whole cascade of adverse pathophysiological processes in the body.

The particular type of pain that may result from the injury is neuropathic pain. It is a burning-scalding pain, usually occurring after a few days or weeks of injury. It is a consequence of injury due to injury to the structures of the central or peripheral nervous system. Therapeutic procedures must be different than in case of pain syndromes accompanying somatic or visceral trauma injuries.

One of the essential elements of effective post-traumatic pain relief is the assessment of its intensity. The intensity of pain should be measured systematically both at rest and in dynamic conditions (movement, cough). According to the researchers, the numerical rating scale (NRS) is the most recommended for older children and adult patients. When assessing the intensity of pain on this scale, we ask the patient to determine how strong is the pain he is currently experiencing, by indicating the appropriate number in the 0-10 range, with 0 corresponding to the opinion “I do not feel pain at all” and 10 – “strongest” pain that I can imagine. ” The scale is easy to apply, moreover, it has been shown to be highly sensitive and reliable in comparison with other scales of pain measurement.

The International Association for the Study of Pain proposed the distinction of three periods after the injury:

  • direct
  • recovery
  • rehabilitation.

These periods differ from each other in the range of pathophysiological changes occurring in the patient, which significantly affects the therapeutic treatment used to relieve pain. It should also be noted that in each of these periods:

primary pain (background pain) present at rest and while performing daily activities by the patient

and “accidental” pain associated with specific therapeutic procedures (dressing changes, manipulations in the wound area, rehabilitation treatments) or appearing during the care of the patient (eg changing the position).

Both primary pain and so-called accidental pain can be generalized or localized pain, which also determines the type of analgesic treatment used in the patient after the injury.

Direct period

Direct-connected pain therapy occurs in extremely stressful circumstances and is caused by direct, massive and prolonged nociceptive stimulation from damaged tissues. The duration of this period is different, usually does not exceed 72 hours, and analgesic treatment is an inseparable part of rescue operations. It should be integrated with other activities, however, due to humanitarian and pathophysiological reasons, they should be implemented as soon as possible. Pain treatment must be a compromise between the requirements of the diagnostic process and the desire to effectively relieve pain after injury.

The treatment of post-traumatic pain in the immediate period is divided into several stages, which are devoted to the following subsections.

Treatment at the scene of an accident and during transport

Everyone suffering from an injury should receive a painkiller as soon as possible.

In patients with pain over 6 according to NRS, an opioid should be given, for example fentanyl, which at a dose of 0.05-0.1 mg is the drug of choice due to the speed and short duration of action, which allows for a strong analgesic effect already during transporting the patient to the hospital. Among the opioid drugs, tramadol (usually at a dose of 50-100 mg) is used successfully at the accident site – a drug that activates opioid receptors and descending pain inhibition routes.

In the case of less extensive injuries (pain intensity 1-5 according to NRS), the patient should be given an intravenously non-opioid analgesic, for example metamizole (0.5-1 g) or paracetamol (1 g) associated with ketoprofen (50-100 mg) or dexketoprofen (25-50 mg).

It must not be forgotten that the administration of opioids to patients after craniocerebral injuries requires special consideration due to the known influence of this group of drugs on the CNS (changes in intracranial pressure, disturbance of consciousness, breathing). In the case of multi-organ trauma, the stabilization of the respiratory and circulatory systems is of fundamental importance, therefore the administration of the opioid is justified by the need for endotracheal intubation and controlled ventilation. In special situations related to injury injured (eg communication), where there are technical difficulties to evacuate from the scene of an accident (eg jam in a broken vehicle), ketamine is used at doses of 0.5-1 mg / kg body weight. Ketamine can also be administered nasally (from special applicators), and the benefits of its use include:

  • effective analgesia
  • reducing the need for opioids
  • reducing the severity of nausea and vomiting
  • no hypotensive effect in patients with low blood pressure
  • inhibition of the activation of proinflammatory cytokines
  • reducing the frequency of post-traumatic stress disorder symptoms
  • no evidence of ketamine induction of increased cerebral blood flow (cerebral blood flow) and intracranial pressure (intracranial pressure)
  • in contrast to opioids, no immunosuppressive action of ketamine.

Painkillers should be administered intravenously (or intramedullary) during this period, because as a result of trauma, the blood flow in muscles and subcutaneous tissue is very quickly impaired. It is important to remember about the obligation to record in the card, what drug, in what dose, what route and when he was ill. This will allow you to quickly provide precise information to the staff of the infirmary, ambulance service or hospital emergency room.

An analgesic procedure in an ambulance of an ambulance or in a hospital

The analgesic procedure initiated at the scene of the accident and carried out during the patient’s transpot should be continued in the hospital or ambulance of the ambulance service.

Analgesic treatment of a non-hospitalized patient

Victims of injuries, which do not require hospitalization after supplying injuries, should be provided with detailed information about pain management at home. For patients reporting “mild” post-traumatic pain with an intensity of 1-4 according to NRS, a non-opioid analgesic is usually sufficient, for example metamizole used in adults orally at a dose of 0.5-1 g every 6 hours or in similar doses of paracetamol.

For patients reporting mild to moderate post-traumatic pain, ie 4-6 according to NRS, use “combined pharmacotherapy” and administer paracetamol orally at a dose of 0.5-1 g every 6 hours and non-steroidal anti-inflammatory drugs (NSAIDs), e.g:

  • ketoprofen (50 mg) p.o. every 6 hours
  • or dexketoprofen (25 mg) p.o. every 12 hours
  • or diclofenac (50 mg) p.o., p.r. every 8 hours
  • or ibuprofen (400 mg) p.o., p.r. every 8 hours
  • or naproxen (500 mg) p.o. every 8 hours.

Importantly, currently combined pharmacotherapy with NSAIDs and paracetamol is one of the basic methods of acute pain relief, because NSAIDs induce effective analgesia (I evidence-based medicine [EBM]), and their anti-inflammatory activity also helps to weaken local inflammation and edema. tissues. Non-steroidal anti-inflammatory drugs also reduce the demand for opioids by about 25-30%, which significantly reduces the incidence of adverse events associated with the use of opioids, such as nausea and vomiting and drowsiness. This allows for earlier physical rehabilitation and discharging the patient into the home.

For patients reporting severe post-traumatic pain above 6-7 according to NRS, metamizole should be used together with NSAIDs and opioid weak (tramadol) or potent (oxycodone) or paracetamol co-administered with a non-steroidal anti-inflammatory drug and an opioid analgesic (eg oxycodone or tramadol). The use of this last drug in drops allows precise adjustment of its dosage to the individual needs of the patient.

In order to facilitate the pain management of victims of injuries, it is proposed to standardize his schedule based on the predicted severity of pain assessed according to the NRS scale and to provide the patient during discharge from the hospital emergency department into a so-called drug package that contains exact – appropriate for a given type of procedure operational – instructions on the use of analgesics (for 3-7 days) and other drugs, for example antiemetic (when opioids are used).

For example, for a patient with post-traumatic pain of more than 6 according to NRS, this package should contain the medicines listed in the adjacent box. The patient should be given a telephone number to an anaesthesiologist or doctors on duty with whom he will be able to communicate in the event of ineffectiveness of the analgesic or adverse effects associated with the prescribed treatment.