Effective Treatment Of Acute Pain Research Articles

The Treatment of Acute Pain in the Emergency Department: A White Paper Position Statement Prepared for the American Academy of Emergency Medicine

BackgroundPain is one of the most common reasons patients present to the emergency department (ED). Emergency physicians should be aware of the numerous opioid and nonopioid alternatives available for the treatment of pain. ObjectivesTo provide expert consensus guidelines for the safe and effective treatment of acute pain in the ED. MethodsMultiple independent literature searches using PubMed were performed regarding treatment of acute pain. A multidisciplinary panel of experts in Pharmacology and Emergency Medicine reviewed and discussed the literature to develop consensus guidelines. RecommendationsThe guidelines provide resources for the safe use of opioids in the ED as well as pharmacological and nonpharmacological alternatives to opioid analgesia. Care should be tailored to the patient based on their specific acute painful condition and underlying risk factors and comorbidities. ConclusionsAnalgesia in the ED should be provided in the most safe and judicious manner, with the goals of relieving acute pain while decreasing the risk of complications and opioid dependence.

Evidence-Based Mini-Review: Are Systemic Corticosteroids an Effective Treatment for Acute Pain in Sickle Cell Disease?

An 18-year-old African-American male with sickle cell disease (SCD) is admitted to the hospital with a vaso-occlusive pain crisis affecting his chest and right upper extremity. He has a history of asthma but does not have a fever or respiratory symptoms, and a chest X-ray is negative for an infiltrate. He is treated with intravenous fluids and morphine. You are asked about the potential efficacy of systemic corticosteroids as an adjunctive treatment for pain control.

Causes and Consequences of Inadequate Management of Acute Pain

Intense acute pain afflicts millions of patients each year. Despite the recently increased focus on the importance of pain control, management of acute pain has remained suboptimal. The objective of this study was to identify through a review of recent literature the barriers to effective treatment of acute pain and the potential consequences of inadequate pain management. A comprehensive literature review was conducted to identify articles relevant to the management of acute pain. Information regarding the underlying causes of inadequate pain management, as well as the sequelae associated with undermanaged pain was extracted and summarized. Studies indicate that treatment of acute pain remains suboptimal due to attitudes and educational barriers on the part of both physicians and patients, as well as the intrinsic limitations of available therapies. Inadequate management of acute pain negatively impacts numerous aspects of patient health, and may increase the risk of developing chronic pain. Although opioids are the preferred treatment for most moderate to severe acute pain, their side effects can impede their use, and thus, their clinical effectiveness. Analgesic regimens with an improved efficacy/tolerability balance have the potential to improve acute pain management, and thus reduce the incidence of chronic pain. Studies examining the use of multiple analgesics with different mechanisms of action suggest that multimodal therapies may offer an improved efficacy/tolerability balance over single agent regimens. There exists a significant need for effective, well-tolerated analgesic therapies to limit the negative consequences of undermanaged acute pain. The use of multimodal therapy has demonstrated increasing promise and is supported by current practice guidelines.

Roles of adenosine receptor subtypes on the antinociceptive effect of sildenafil in rat spinal cord

We recently found that the antinociceptive effects produced by intrathecal administration of sildenafil, a phosphodiesterase 5 inhibitor, were reversed by a nonspecific adenosine receptor antagonist, suggesting that adenosine receptors are involved in sildenafil-induced antinociception. Four adenosine receptor subtypes have been identified: A 1, A 2A, A 2B, and A 3. We examined the involvement of spinal adenosine receptor subtypes in the antinociceptive effects of intrathecal sildenafil. Intrathecal catheters were implanted in male SD rats, and nociception was assessed using the formalin test, which consisted of a subcutaneous injection of 50 μl of 5% formalin solution into the hind paw. We examined the effects of an adenosine A 1 receptor antagonist (CPT), an adenosine A 2A receptor antagonist (CSC), an adenosine A 2B receptor antagonist (alloxazine), and an adenosine A 3 receptor antagonist (MRS 1220) on sildenafil-induced antinociception. Intrathecal sildenafil suppressed formalin-induced flinching during phases 1 and 2 of the test in a dose-dependent manner. Intrathecal CPT, CSC, alloxazine, and MRS 1220 all suppressed the antinociceptive effects of sildenafil during both phases of the formalin test. These results suggest that sildenafil is an effective treatment for acute pain and the facilitated pain state at the spinal level. Additionally, spinal adenosine A 1, A 2A, A 2B, and A 3 receptors may play a role in sildenafil-induced antinociception.

How to design an opioid drug that causes reduced tolerance and dependence

Mu opioid receptor (MOR) agonists such as morphine are extremely effective treatments for acute pain. In the setting of chronic pain, however, their long-term utility is limited by the development of tolerance and physical dependence. Drug companies have tried to overcome these problems by simply "dialing up" signal transduction at the receptor, designing more potent and efficacious agonists and more long-lasting formulations. Neither of these strategies has proven to be successful, however, because the net amount of signal transduction, particularly over extended periods of drug use, is a product of much more than the pharmacokinetic properties of potency, efficacy, half-life, and bioavailability, the mainstays of traditional pharmaceutical screening. Both the quantity and quality of signal transduction are influenced by many regulated processes, including receptor desensitization, trafficking, and oligomerization. Importantly, the efficiency with which an agonist first stimulates signal transduction is not necessarily related to the efficiency with which it stimulates these other processes. Here we describe recent findings that suggest MOR agonists with diminished propensity to cause tolerance and dependence can be identified by screening drugs for the ability to induce MOR desensitization, endocytosis, and recycling. We also discuss preliminary evidence that heteromers of the delta opioid receptor and the MOR are pronociceptive, and that drugs that spare such heteromers may also induce reduced tolerance.

Therapie chronischer Schmerzen

Pain is one of the major complaints leading to doctor visits. Therefore basic knowledge of frequent pain diagnoses and possible treatment approaches is essential. Numerous medical and interventional therapeutic options are available for causal or symptomatic treatment of pain. The treatment of neuropathic pain is often difficult and demands special knowledge. Antidepressants like amitriptyline and anticonvulsive drugs are the first choice in these cases. Also interventional approaches are useful, such as spinal cord stimulation for angina pectoris. For the treatment of complex regional pain syndrome and phantom pain the use of mirror feed-back is a new effective method for pain relief. The only way to prevent from development of chronic pain is the early and effective treatment of acute pain.

Choix de l'analgésie systémique selon le terrain

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.

Treatment of Pain Due to Vaso-Occlusive Crises (VOC) in Adults with Sickle Cell Disease (SCD): Limited Awareness of Available Guidelines.

SCD is characterized by frequent VOC marked by severe pain often requiring emergency department visits and inpatient admissions for treatment with parenteral opioids. Guidelines for managing pain due to VOC, published in the US (in 1999 and 2002) and England (in 2003) suggest: 1) rapid initiation of parenteral opioids (within 15–30 min of arrival); 2) use of an adequate opioid starting dose (usually 5–10 mg or 0.1 mg/kg of morphine intravenously); 3) use of frequent repeat opioid doses (every 15–30 min) until pain is significantly improved; and 4) selection of an alternative treatment regimens based on an individual’s prior opioid-response history. However, attending physicians on the adult hematology service were generally unaware of the existence of these guidelines. Thus, all standard textbooks in internal medicine (N=7), hematology (N=3) and emergency medicine (N=3) available in hard-copy or on-line at the Yale University School of Medicine library and published after 2002 were reviewed for recommendations regarding: a) treatment of pain due to VOC; b) treatment of pain due to acute myocardial infarction; and c) treatment of bleeding due to Hemophilia A. For treatment of pain due to VOC, none of the texts indicated a target time for initiating opioid therapy and only 2 texts commented on the need to individualize therapy based on patient history. Suggested starting doses of opioids were not given in 5 of 13 references and were lower than guideline recommendations in one additional text. The frequency of opioid administration was not noted in 6 reference books; only 2 texts suggested repeat doses within a 20–30 minute interval; one text suggested an interval of 1 to 3 hours; and the other 4 texts suggested intervals of 2 to 4 hours. Overall, appropriate initial opioid doses were provided in 7 texts (54%); recommendations for dosing frequency were consistent with guidelines in 2 texts (15%); the need to individualize therapy based on patient history was noted in 2 texts (15%); and no text indicated a target time for the initiation of analgesic therapy. In 1996, guidelines for opioid use in the treatment of pain due to acute myocardial infarction suggested doses of 2–4 mg of intravenous morphine administered as often as every 5 minutes. Of the 10 relevant internal medicine and emergency medicine texts reviewed, recommendations were not given in one text but both the morphine dose and frequency of administration were consistent with these guidelines in the remaining 9 (90%). Finally, for hemophilia A, all 13 reference works provided specific and consistent directions for the calculation of Factor VIII treatment requirements while 10 texts (77%) described available Factor VIII preparations. In conclusion, standard texts do not present adequate infomation to permit effective treatment of acute pain in SCD. Since guidelines for frequent opioid use to treat pain due to acute myocardial infarction are given in most texts, this cannot be explained by constraints on recommending opioid therapy per se. Nor can it be explained by the rarity of SCD since more detailed information is provided for the treatment of hemophilia, an even less common disorder. It is of note then that only 5 of 13 texts (38%) reassure readers that narcotic addiction is infrequent in SCD patients while 9 of 10 texts (90%) offer this reassurance when discussing cancer pain treatment. Thus, greater educational efforts are needed to facilitate pain treatment in the VOC of SCD.

Chronischer Schmerz im ärztlichen Alltag

Acute or chronic pain are the most frequent reasons to seek medical help. Primarily acute pain is a symptom and warning sign. However, insufficient treatment of acute pain may induce a change to a chronic long lasting pain illness. Therefore a consequent immediate treatment is essential. Chronic pain is a bio-psycho-social illness. In this situation pharmacotherapy or any other monotherapy alone is no longer effective. Interdisciplinary treatment is needed. Effective treatment of acute pain to prevent from long lasting pain episodes is an essential and the only way to prevent from enormous financial consequences of chronic pain.

Preventing the Development of Complex Regional Pain Syndrome after Surgery

COMPLEX regional pain syndrome (CRPS), previously known as reflex sympathetic dystrophy (RSD), is used to describe a syndrome of pain and sudomotor or vasomotor instability. This pain syndrome usually has an initiating noxious event in the periphery, is not limited to the distribution of a single nerve, and is disproportionate to the inciting event. The Consensus Conference of the International Association for the Study of Pain has subclassified CRPS into two forms: CRPS I (formerly RSD) and CRPS II (formerly causalgia). According to the International Association for the Study of Pain, the diagnosis of CRPS I requires (1) continuing pain, allodynia, or hyperalgesia disproportionate to the injury; (2) evidence at some time of edema, changes in skin blood flow, or abnormal sudomotor activity in the region of pain; and (3) no other conditions that would otherwise account for the degree of pain and dysfunction. Motor disturbances and trophic changes, such as altered nail and hair growth, may be observed in some cases. CRPS II is a pain syndrome that starts after a nerve injury and is not necessarily limited to the distribution of the injured nerve. The diagnostic criteria are the same as those of CRPS I. Patients with CRPS I or CRPS II can have sympathetically maintained pain or sympathetically independent pain. Sympathetically maintained pain, a term introduced in 1986 by Roberts, is pathologic pain that is supported by sympathetic efferent activity, circulating catecholamines, and/or increased sensitivity of -adrenergic receptors. Sympathetically maintained pain is identified by the ability to lessen the pain by sympatholytic blocks or interventions. Sympathetically independent pain has components of pain from sources other than sympathetic innervation and is believed to be most commonly observed in advanced cases of CRPS that do not respond to sympathetic blocks. Patients with CRPS may present with components of only sympathetically maintained pain or sympathetically independent pain or, more commonly, a combination of pain from each. Despite increasing research interest, little is known regarding which patients are at increased risk for development of postoperative CRPS and what the optimal perioperative treatment strategy is for those patients undergoing surgery who have a previous history of CRPS. This review outlines the surgical procedures that are believed to increase risk for development of CRPS and describes pharmacologic and regional analgesic techniques that may be of benefit for preventing the development of CRPS after surgery.

Double-blind, randomized, placebo-controlled trial comparing rofecoxib with dexketoprofen trometamol in surgical dentistry

Rofecoxib, a selective cyclooxygenase-2 inhibitor, and dexketoprofen trometamol, a single isomer non-steroidal anti-inflammatory drug (NSAID), are available for the treatment of acute pain. Both are claimed to have fewer adverse effects than traditional NSAIDs. We have compared them in a clinical setting. We performed a double-blind randomized controlled trial involving 120 patients undergoing surgical removal of a single mandibular third molar at the Edinburgh Dental Institute. Those who developed moderate pain within 4 h of the procedure were allocated to one of three groups: rofecoxib 50 mg (Group RO, n=37); dexketoprofen trometamol 25 mg (Group DE, n=42); or placebo (Group PL, n=41). Participants monitored pain intensity and pain relief for 24 h using visual analogue scales (VAS) and verbal rating scales (VRS). The summed, time-weighted pain relief score to 8 h derived from the VRS (TOTPAR 8) was used as the primary outcome variable. No significant difference was demonstrated between Groups RO and DE using TOTPAR 8 as the primary outcome variable. Both drugs were significantly different compared with placebo. Rescue analgesia during the trial period was required by only 15 out of 37 subjects in Group RO, but 35 out of 42 subjects in Group DE. The median times to use of rescue medication were 150 (Group PL), 398 (Group DE) and 1440 min (Group RO). Both drugs were well tolerated and adverse events reported were mild to moderate in severity. Rofecoxib and dexketoprofen trometamol are effective treatments for acute pain using a dental pain model and are well tolerated. Rofecoxib has a longer duration of action as a single dose and gave adequate analgesia for over half of that study group; patients in the dexketoprofen trometamol group needed more rescue analgesia.

Clinically Important Change in the Visual Analog Scale after Adequate Pain Control

Abstract Objectives: To define the minimum clinically important difference (MCID) for the visual analog scale (VAS) of pain severity by measuring the change in VAS associated with adequate pain control. Methods: The authors conducted a prospective, observational study. Adult emergency department (ED) patients with acute pain (<72 hours) were eligible. Patients rated their pain severity on a 100‐mm VAS on presentation and at discharge. Patients were asked if they would accept any analgesic, then if they would accept a parenteral analgesic before treatment. At discharge, they were asked whether they had received adequate pain control. Results: The authors enrolled 143 patients (mean age, 36 years; 54% female). The mean decrease in VAS was −30.0 mm (95% confidence interval [CI] =−36.4 to −23.6) for the 116 of 143 (81%) patients with adequate pain control at discharge vs. −5.7 (95% CI =−11.2 to −0.3) for the 27 with inadequate pain control (p < 0.001). At discharge, the mean VAS was 31.3 mm for those with adequate pain control vs. 55.1 for those without. Mean VAS for the 114 of 143 patients who would accept any analgesics initially was 64.7 vs. 47.1 for the 29 reporting no analgesic need. Initially, 77 patients would accept parenteral analgesics (mean VAS = 72.5 mm). Conclusions: A mean reduction in VAS of 30.0 mm represents a clinically important difference in pain severity that corresponds to patients' perception of adequate pain control. Defining MCID based on adequate analgesic control rather than minimal detectable change may be more appropriate for future analgesic trials, when effective treatments for acute pain exist.