Recognizing And Monitoring The Painful Patient Susan Clark, LVT, VTS(ECC) The Fifth Vital Sign. Pain control is part of the accepted standard of care in veterinary medicine. The ability to recognize the many ways in which our patients may exhibit pain is an important part of patient monitoring. How does pain affect your patient? Reluctant to move. Unwilling to eat. Hypertension Tachycardia Anxiety Poor quality of life. When pain is controlled. Up and moving sooner. Eating sooner. Healing quicker. Improved life quality. Home sooner! Happy pet, happy owner! SYMPTOMS OF PAIN Restlessness Reluctance to move Depression Aggression Anxiety 1
Avoidance Vocalizing Tense/Guarding Licking/ Chewing May turn to look at painful area Changes in facial expression or posture Prayer Posture Splinting Before pain medication. After pain meds.. Acute vs Chronic Arthritis Neoplasia Chronic disease Trauma Surgery Acute illness 2
WIND-UP (Allodynia) Patients who have been in pain for some time (hours to days) can become overly sensitive to any stimulus, which will be perceived as painful. Patients in wind-up may require larger doses of analgesics to bring pain under control. Anticipatory Patients may come to anticipate that what we are about to do will cause pain. These patients often react when approached, before being touched or moved. PAIN ASSESSMENT Assessment of pain is a subjective opinion. There will always be some variance from person to person. The use of a pain scoring system with specific guidelines will help to standardize how you assess pain in your clinic. 3
2006/PW Hellyer, SR Uhrig, NG Robinson Colorado State University Pain should be frequently monitored along with other parameters such as temperature, pulse, respiration & blood pressure. Is pain control needed? Is current pain control working? Observe patient before approaching cage. Observe patient during interaction, and with gentle palpation of affected area. 4
Medications Opioids Non-steroidal anti-inflammatory drugs (NSAID) Alpha-2 Adrenergic Agonist Corticosteroids N-methyl-D-aspartate (NMDA) Receptor Antagonist Local Anesthetics Miscellaneous mu agonists Partial mu agonist Partial agonist/ antagonist OPIOIDS morphine, hydromorphone, methadone, fentanyl, codeine Strongest pain control, may cause respiratory depression, decreased G.I. motility, nausea; reversal agent available (naloxone) buprenorphine, tramadol Mild to moderate pain control, rare respiratory depression, can be partially reversed. Buprenorphine has a strong affinity to mu receptors and may take over receptors from pure mu agonist. butorphanol Mild pain control at best, for short time frame (< 1 hour). Good sedative effects. Kappa agonist. WILL ANTAGONIZE MU AGONIST. NSAIDS carprofen, meloxicam, deracoxib, firocoxib, robenacoxib, etc. COX-1 or COX-2 inhibitors Anti-inflammatory, antipyretic, analgesic. Can cause GI upset; gastric ulceration. Contraindicated for use in patients with renal or hepatic compromise. Caution with use in cats. Alpha-2 Adrenergic Agonist dexmetetomidine Strong sedative effects. Mild analgesic properties. Best used in conjunction with opioids. Can cause peripheral & cardiac vasoconstriction, bradycardia, hypertension. Most side effects are avoided with low dose constant rate infusions (CRI). Do not use in patients with cardiac, hepatic or renal disease, or unstable patients. Reversal agent available. (atipamezole) Corticosteroids prednisone, dexamethasone Anti-inflammatory agent. No direct analgesic effects. May be helpful for cases in which NSAIDS are contraindicated. May cause GI ulceration. Long term use may lead to iatrogenic Cushing s Disease; must wean to avoid iatrogenic Addison s Disease. 5
NMDA Receptor Antagonist Ketamine Dissociative anesthetic. Mild analgesia. Best used in multimodal CRI. May cause elevated heart rate, dysphoria. Local Anesthetic lidocaine Short acting (1 to 3 hours) Analgesic effects with IV administration. (Unknown action) May cause nausea. (when given IV) bupivacaine Last ~ 6 hours. Epidurals, soaker cath., other blocks. bupivacaine liposome suspension. Last ~ 72 hours. Gama-aminobutyric acid (GABA) analogue gabapentin Used for neuropathic and chronic pain, in conjunction with other analgesics. May cause sedation, vomiting, diarrhea. Muscle Relaxers i.e. methocarbamol Anxiolytics & Sedatives diazepam; midazolam trazodone May increase risk of serotonin syndrome. Use with caution in patients with hepatic dz. acepromazine Can cause vasodilation. Avoid in unstable patients or those with cardiac dz. Multimodal Analgesia Combining analgesics from different categories can have a synergistic effect, for increased analgesia. Often lower doses of each may be used, reducing the risk of side effects. 6
Constant Rate Infusions (CRI) Delivers steady dose of medication into bloodstream. LOCAL ANESTHETIC BLOCKS Incisional Splash Regional Soaker cath. Chest tube Epidurals Possible side effects of analgesics. Dysphoria Nausea Sedation Weakness Abnormal heart rate Serotonin syndrome Renal/Hepatic compromise Symptoms of Dysphoria Anxious Vocalizing Flailing Abnormal mentation Other Interventions Cold compress Warm compress Acupuncture Laser Therapy Massage Pain management = Standard of Care Use of a pain score assessment is helpful for continued monitoring. There are many options available to treat both acute and chronic pain. IN SUMMARY. 7
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