Multimodal postoperative pain management

A comparison of 2 intravenous patient-controlled analgesia modes after spinal fusion surgery: Constant-rate background infusion versus variable-rate feedback infusion, a randomized controlled trial

BACKGROUND

Conventional intravenous patient-controlled analgesia (PCA), which usually involves constant-rate background infusion plus demand dosing, may cause adverse effects or insufficient analgesia. When variable-rate feedback infusion plus demand dosing mode is used, the infusion rate can be changed according to the patient's needs.

METHODS

In this prospective randomized double-blind study, 78 adults who were undergoing spinal fusion surgery were randomly allocated to either the constant-rate background infusion plus demand dosing group (group C) or the variable-rate feedback infusion plus demand dosing group (group V). The number of demands, volume delivered, numerical rating scale (NRS) score, adverse effects and the use of rescue analgesics were examined at 30 minutes after the operation in the post-anesthesia care unit, and at 6, 12, 24, and 48 hours.

RESULTS

The number of demands was significantly lower in group V than in group C at 12-24 hours (4.59 ± 4.31 vs 9.21 ± 6.79 times, P = .001) and over the total period. The volume delivered via PCA was significantly lower in group V than in group C at 12 to 24 hours (13.96 ± 13.45 vs 21.19 ± 8.66 mL, P = .006), 24 to 48 hours (13.39 ± 12.44 vs 33.6 ± 12.49 mL, P = .000), and over the total period. NRS scores, administration of rescue analgesics, and postoperative nausea and vomiting showed no between-group differences.

CONCLUSIONS

Variable-rate feedback infusion plus the demand dosing mode can control postoperative pain more efficiently, with lower dosages of analgesics, than constant-rate background infusion plus demand dosing in patients who undergo spinal fusion surgery.

Randomized clinical trial of dexketoprofen/tramadol 25 mg/75 mg in moderate-to-severe pain after total hip arthroplasty

Background. The aim was to evaluate the analgesic efficacy and safety of the dexketoprofen/tramadol 25 mg/75 mg fixed-dose combination vs dexketoprofen (25 mg) and tramadol (100 mg) in moderate-to-severe acute pain after total hip arthroplasty.

Methods. This was a randomized, double-blind, parallel-group study in patients experiencing pain of at least moderate intensity on the day after surgery, compared with placebo at first administration to validate the pain model. The study drug was administered orally every 8 h throughout a 5 day period. Rescue medication, metamizole 500 mg, was available during the treatment period. The evaluation of efficacy was based on patient assessments of pain intensity and pain relief. The primary end point was the mean sum of the pain intensity difference values throughout the first 8 h (SPID₈).

Results. Overall, 641 patients, mean age 62 (range 29–80) yr, were analysed; mean (sd) values of SPID₈ were 247 (157) for dexketoprofen/tramadol, 209 (155) for dexketoprofen, 205 (146) for tramadol, and 151 (159) for placebo. The primary analysis confirmed the superiority of the combination over dexketoprofen 25 mg (P=0.019; 95% confidence interval 6.4–73) and tramadol 100 mg (P=0.012; 95% confidence interval 9.5–76). The single components were superior to placebo (P<0.05), confirming model sensitivity. Most secondary analyses supported the superiority of the combination. The incidence of adverse drug reactions was low and similar among active treatment groups.

Conclusion. The efficacy results confirmed the superiority of dexketoprofen/tramadol over its single components, even at higher doses (tramadol), with a safety profile fully in line with that previously known for these agents in monotherapy.

Clinical trial registration. EudraCT 2012-004548-31 (https://www.clinicaltrialsregister.eu/ctr-search/search?query=eudract_number:2012-004548-31);

ClinicalTrials.gov NCT01902134 (https://www.clinicaltrials.gov/ct2/show/NCT01902134?term=NCT01902134&rank=1).

Impact of preoperative continuous femoral blockades on morphine consumption and morphine side effects in hip-fracture patients: A randomized, placebo-controlled study

BACKGROUND

Upon arrival at the emergency department, hip-fracture pain relief is usually carried out via systemic opioids. Continuous nerve blocks are efficient in the postoperative period, but have not been evaluated preoperatively. This study compared the reduction in morphine consumption and related side effects of a continuous femoral block with a single shot block in hip-fracture patients.

METHODS

Hip-fracture patients admitted to the emergency department received a femoral nerve catheter, with a single lidocaine injection. They were then randomized to ropivacaine (group R) or saline continuous infusion (placebo, group P) in a double-blind manner. Morphine consumption and side effects were prospectively collected until the 24th postoperative hour.

RESULTS

Sixty patients were included and 55 analyzed. There were no significant differences between the 2 groups regarding fracture types, delay before surgery (median [Q1-Q3]: 21.3 [14.5-29.4] versus 20.8 [15.7-36.2] hours for groups R and P, respectively; P=0.87) and catheter duration (47.5 [39.8-52.4] versus 42.5 [32.1-50.5] hours, P=0.29). Total morphine consumption was not significantly decreased in group R (5 [0-14] versus 8 [4.5-11] mg, P=0.3) and pain scores were similar (mean±SD; VAS 29±15/100 versus 33±13, P=0.3). We observed a significant reduction in morphine adverse effects (31% versus 69% for groups R and P, respectively; P<0.01), mainly nausea (31% versus 59%, P=0.03). One morphine side effect could be avoided for every 5 patients treated.

CONCLUSION

Preoperative continuous femoral blockades using ropivacaine reduce morphine side effects (mainly nausea) in hip-fracture patients without reducing morphine consumption.

Administration of analgesics after rotator cuff repair: a prospective clinical trial comparing glenohumeral, subacromial, and a combination of glenohumeral and subacromial injections

BACKGROUND

Local analgesic injections are commonly used for pain relief after shoulder surgery. The aim of this study was to compare the efficacy of local injections administered in the glenohumeral joint, the subacromial space, or both locations after arthroscopic rotator cuff repair.

METHODS

Between March 2011 and December 2011, 121 consecutive patients who had undergone arthroscopic rotator cuff repair surgery were enrolled in the study and all patients were randomly allocated to 3 groups. In group 1, 40 patients received a postoperative glenohumeral injection of bupivacaine (20 mL) and lidocaine (10 mL). In group 2, 42 patients received the same postoperative injection, but it was administered in the subacromial space. In group 3, 39 patients received the same amount of local anesthesia but with half injected in the glenohumeral joint and half in the subacromial space. The visual analog scale was used to assess pain intensity before surgery and at postoperative hours 1, 2, 6, 12, and 24. Demerol was used as a postinjection rescue analgesic, and the total number of administrations was recorded at each time point.

RESULTS

There were no significant differences between groups in patient age, sex, or rotator cuff tear size (P > .05). The visual analog scale scores for pain between each group were not significantly different at any time point, including before surgery (P > .05). In addition, the amount of supplementary analgesic administered was not significantly different between the groups (P > .05).

CONCLUSION

Injection of local analgesics after arthroscopic rotator cuff repair relieves postoperative pain regardless of the injection location.

Evaluation of a Multimodal Approach to Postoperative Pain in Patients Undergoing Flank Incision in the Urology Operating Room

OBJECTIVE

In this study, we evaluated subcutaneous (sc) morphine in combination with multimodal analgesia for postoperative pain control after radical nephrectomy and pyeloplasty with flank incision.

METHODS

Forty-nine patients under The American Society of Anesthesiologists Physical Status classification (ASA) I-III aged 18-85 years undergoing radical nephrectomy and pyeloplasty with flank incision were included in this prospective, randomised study. The patients were divided into two groups (Group O [n=25] and Group M [n=24]) and received standard general anaesthesia. Tramadol (100 mg) and paracetamol (100 mg) were given intravenously before fascia closure and 20 mL of 0.25% levobupivacaine was injected locally at surgical incisions in all patients. Patients in Group M also received 0.1 mg kg(-1) morphine subcutaneously. Patient-controlled analgesia (PCA) with tramadol was used for postoperative pain control in both groups. Postoperative pain scores (VAS), vital parameters, side effects, the need for rescue analgesia during 24 hours postoperatively, and patient satisfaction were recorded.

RESULTS

Groups were comparable with respect to demographic data, ASA status, and duration of surgery. There were no significant differences between the groups in postoperative PCA tramadol consumption, rescue analgesia, side effects, or vital parameters. Postoperative pain scores (VAS) in Group M were significantly lower at 30, 45, 60, and 120 minutes compared to Group O (p<0.05).

CONCLUSION

In patients undergoing radical nephrectomy and pyeloplasty with flank incision, subcutaneous morphine in combination with multimodal analgesia decreases early postoperative pain scores compared to multimodal analgesia alone.

Complementary and alternative medicine: nurses' attitudes and knowledge

Despite significant evidence for the integration of complementary and alternative medicine (CAM) into professional nursing practice, gaps exist regarding nurses' baseline knowledge, beliefs of efficacy, and learning needs for further education to facilitate the integration of CAM into nursing practice. The top three conditions which adults identified for using CAM were back pain, neck pain, and joint pain. CAM can offer nurses additional treatment options for managing their patients' pain and discomfort. The California Board of Registered Nursing (BRN) identifies that nurses can help provide the missing link between conventional Western medicine and CAM therapies. Nurses cannot successfully advocate for CAM therapies, nor understand their patients' prior use of such treatments, unless they themselves are familiar with both the risks and the benefits of these practices. It is necessary to first establish nurses' baseline knowledge and beliefs related to CAM so that adequate educational programs can be initiated to help mitigate the barriers to incorporating CAM into the acute care setting. This descriptive study explores registered nurses' attitudes and knowledge related to CAM by using the Nurse Complementary and Alternative Medicine Nursing Knowledge and Attitudes Survey developed by Rojas-Cooley and Grant. Nurses in this study demonstrated limited self-reported knowledge of basic CAM terminology and CAM practices.

Multimodal approach to postoperative pain control in patients undergoing rotator cuff repair

PURPOSE

This prospective study was undertaken to compare the effectiveness and safety of a multimodal pain control protocol with those of intravenous patient-controlled analgesia in rotator cuff repair.

METHODS

Seventy patients scheduled for rotator cuff repair were randomized to either a multimodal pain control group (group 1, 40 patients) or an intravenous patient-controlled analgesia group (group 2, 30 patients). We compared these two groups with respect to level of pain before surgery to the fifth postoperative day, duration of postoperative rehabilitation, consumption of additional analgesics, and adverse effects.

RESULTS

Mean visual analogue scale scores immediately after surgery (day 0) and on postoperative days 1-5 were 6.9, 5.5, 4.3, 3.3, 3.0, and 2.6 in group 1 and 7.8, 5.9, 4.4, 4.7, 4.3, and 3.7 in group 2. Pain relief was significantly better in group 1 on days 0, 3, 4, and 5 (P = 0.026, 0.006, 0.010, and 0.009, respectively). Furthermore, functional recovery occurred earlier in group 1. No significant differences were observed between the two groups with respect to nausea, vomiting, urinary retention, and headache (n.s.), but group 1 was found to be significantly less likely to experience dizziness or urticaria (P = 0.007, 0.017, respectively). One other significant difference was observed: 1 patient (2.5%) in group 1 and 6 patients (20%) in group 2 discontinued regimen because of medication-related adverse effects (P = 0.016).

CONCLUSION

The multimodal pain control protocol was found to offer more effective postoperative pain control with fewer adverse effects than intravenous patient-controlled analgesia. However, achieving adequate pain control within the first 48 h of surgery remains challenging, and thus, the developments of more effective and safer multimodal pain control protocols are required.

Tapentadol in the management of chronic low back pain: a novel approach to a complex condition?

Chronic pain affects approximately 1 in 5 people in Europe, and around half of sufferers receive inadequate pain management. The most common location is the lower back. Pharmacological treatment of this condition is challenging because of the range of causative mechanisms and the difficulty of balancing analgesic efficacy and tolerability. An international panel of clinical pain specialists met in September, 2009, to discuss the treatment of chronic low back pain, and to review preclinical and clinical data relating to the new analgesic, tapentadol. A lack of consensus exists on the best treatment for low back pain. The range of regularly prescribed pharmacological agents extends from nonopioids (paracetamol, NSAIDs, and COX-2 inhibitors) to opioids, antidepressants and anticonvulsants. Pain relief may be compromised, however, by an undetected neuropathic component or intolerable side effects. Treatment is potentially life-long and effective analgesics are urgently needed, with demonstrable long-term safety. Combining separate agents with different mechanisms of action could overcome the limitations of present pharmacological therapy, but clinical evidence for this approach is currently lacking. Tapentadol combines μ-opioid agonism with noradrenaline reuptake inhibition in a single molecule. There is strong evidence of synergistic antinociception between these two mechanisms of action. In preclinical and clinical testing, tapentadol has shown efficacy against both nociceptive and neuropathic pain. Preclinical data indicate that tapentadol’s μ-opioid agonism makes a greater contribution to analgesia in acute pain, while noradrenaline reuptake inhibition makes a greater contribution in chronic neuropathic pain models. Tapentadol also produces fewer adverse events than oxycodone at equianalgesic doses, and thus may have a ‘μ-sparing effect’. Current evidence indicates that tapentadol’s efficacy/tolerability ratio may be better than those of classical opioids. However, further research is needed to establish its role in pain management.

Tapentadol in pain management: a μ-opioid receptor agonist and noradrenaline reuptake inhibitor

Several mechanisms can be proposed to explain an apparent synergistic analgesic action between μ-opioid and α(2)-adrenergic receptor agonists. Combining both effects in a single molecule eliminates the potential for drug-drug interactions inherent in multiple drug therapy. Tapentadol is the first US FDA-approved centrally acting analgesic having both μ-opioid receptor agonist and noradrenaline (norepinephrine) reuptake inhibition activity with minimal serotonin reuptake inhibition. This dual mode of action may make tapentadol particularly useful in the treatment of neuropathic pain. Having limited protein binding, no active metabolites and no significant microsomal enzyme induction or inhibition, tapentadol has a limited potential for drug-drug interactions. Clinical trial evidence in acute and chronic non-cancer pain and neuropathic pain supports an opioid-sparing effect that reduces some of the typical opioid-related adverse effects. Specifically, the reduction in treatment-emergent gastrointestinal adverse effects for tapentadol compared with equianalgesic pure μ-opioid receptor agonists results in improved tolerability and adherence to therapy for both the immediate- and extended-release formulations of tapentadol.

21. Phantom pain

Phantom pain is pain caused by elimination or interruption of sensory nerve impulses by destroying or injuring the sensory nerve fibers after amputation or deafferentation. The reported incidence of phantom limb pain after trauma, injury or peripheral vascular diseases is 60% to 80%. Over half the patients with phantom pain have stump pain as well. Phantom pain can also occur in other parts of the body; it has been described after mastectomies and enucleation of the eye. Most patients with phantom pain have intermittent pain, with intervals that range from 1 day to several weeks. Even intervals of over a year have been reported. The pain often presents itself in the form of attacks that vary in duration from a few seconds to minutes or hours. In most cases, the pain is experienced distally in the missing limb, in places with the most extensive innervation density and cortical representation. Although there are still many questions as to the underlying mechanisms, peripheral as well as central neuronal mechanisms seem to be involved. Conservative therapy consists of drug treatment with amitriptyline, tramadol, carbamazepine, ketamine, or morphine. Based on the available evidence some effect may be expected from drug treatment. When conservative treatment fails, pulsed radiofrequency treatment of the stump neuroma or of the spinal ganglion (DRG) or spinal cord stimulation could be considered (evidence score 0). These treatments should only be applied in a study design.

Tapentadol immediate-release for acute pain

Tapentadol is a novel opioid agent with a dual mode of analgesic action. The inhibition of norepinephrine combined with moderate opioid agonist activity results in fewer gastrointestinal adverse effects compared with equianalgesic doses of oxycodone. Having no active metabolites and minimal protein binding, tapentadol provides improved tolerability with a lower potential for pharmacokinetic drug-drug interactions or accumulation with impaired renal or hepatic function when compared with oxycodone. Tapentadol immediate-release is currently US FDA approved for moderate-to-severe acute pain in adults.

The determination and application of fixed-dose analgesic combinations for treating multimodal pain

When the pathophysiology of a medical condition is multimodal, ie, related to multiple physiological causes or mediated by multiple pathways, the optimal strategy can be to use a drug or a combination of drugs that contribute multiple mechanisms to the therapeutic endpoint. In such situations, a rational multimodal approach can also result in the fewest adverse effects. We discuss the quantitative analysis of multimodal action using the treatment of pain as a practical example and give examples of its application to some widely used analgesic drugs.

PERSPECTIVE

This article reviews the medical relevance of the quantitative evaluation of drug combinations, using pain and combinations of analgesics as specific examples. Such measure can help clinicians who seek to maximize therapeutic effect while simultaneously minimizing adverse effects.

Tapentadol immediate release: a new treatment option for acute pain management

The undertreatment of acute pain is common in many health care settings. Insufficient management of acute pain may lead to poor patient outcomes and potentially life-threatening complications. Opioids provide relief of moderate to severe acute pain; however, therapy with pure μ-opioid agonists is often limited by the prevalence of side effects, particularly opioid-induced nausea and vomiting. Tapentadol is a novel, centrally acting analgesic with 2 mechanisms of action, μ-opioid receptor agonism and norepinephrine reuptake inhibition. The analgesic effects of tapentadol are independent of metabolic activation and tapentadol has no active metabolites; therefore, in theory, tapentadol may be associated with a low potential for interindividual efficacy variations and drug-drug interactions. Previous phase 3 trials in patients with various types of moderate to severe acute pain have shown that tapentadol immediate release (IR; 50 to 100 mg every 4 to 6 hours) provides analgesia comparable to that provided by the pure μ-opioid agonist comparator, oxycodone HCl IR (10 or 15 mg every 4 to 6 hours), with a lower incidence of nausea, vomiting, and constipation. Findings suggest tapentadol may represent an improved treatment option for acute pain.

Efficacy of multimodal pain control protocol in the setting of total hip arthroplasty

BACKGROUND

This study evaluated the benefits and safety of a multimodal pain control protocol, which included a periarticular injection of local anesthetics, in patients undergoing total hip arthroplasty.

METHODS

Between March 2006 and March 2007, 60 patients undergoing unilateral total hip arthroplasty were randomized to undergo either a multimodal pain control protocol or a conventional pain control protocol. The following parameters were compared: the preoperative and postoperative visual analogue scales (VAS), hospital stay, operative time, postoperative rehabilitation, additional painkiller consumption, and complication rates.

RESULTS

There was no difference between the groups in terms of diagnosis, age, gender, and BMI. Although both groups had similar VAS scores in the preoperative period and on the fifth postoperative day, there was a significant difference between the groups over the four-day period after surgery. There were no differences in the hospital stay, operative time, additional painkiller consumption, or complication rate between the groups. The average time for comfortable crutch ambulation was 2.8 days in the multimodal pain control protocol group and 5.3 days in the control group.

CONCLUSIONS

The multimodal pain control protocol can significantly reduce the level of postoperative pain and improve patients' satisfaction, with no apparent risks, after total hip arthroplasty.

Extended-release epidural morphine (DepoDur): review and safety analysis

Extended-release epidural morphine (EREM) provides effective postoperative analgesia for 48 h following injection. It is administered as a single bolus into the lumbar epidural space, and is indicated for lower abdominal and lower extremity surgery associated with moderate-to-severe pain. While its efficacy has been well documented in randomized controlled trials, the safety and clinically appropriate dosing are less well defined. A meta-analysis approach was used to assess the adverse effects of EREM (n = 801) in comparison with intravenous opioids and standard epidural morphine. EREM 15 mg or greater was associated with a trend towards a higher incidence of hypoventilation (odds ratio: 0.48; 95% confidence interval [CI]: 0.21-1.09; p = 0.081; number-needed-to-treat [NNT] = 14) compared with placebo. The incidence of pruritus was significantly higher for all EREM doses compared with both placebo (p = 0.004) and standard epidural morphine (p = 0.03). Vomiting was also increased with EREM 15 mg or greater compared with placebo (odds ratio: 0.40; 95% CI: 0.18-0.89; p = 0.02; NNT = 5). A multimodal analgesic regime is recommended to permit the use of lower EREM doses, thus reducing the risk for adverse effects including respiratory depression. Prophylactic time-contingent antiemetics are also recommended when EREM is used.

Propoxyphene prescribing among populations older and younger than age 65 in a tertiary care hospital

OBJECTIVE

To evaluate the proportion of patients aged 65 years and older who are prescribed propoxyphene (PP) versus those aged 65 and younger.

DESIGN

Retrospective cross-sectional study.

SETTING

Tertiary care facility.

PARTICIPANTS

Adult patients admitted to the hospital between January 1, 2005, and June 30, 2005, and prescribed either hydrocodone (HC) or PP.

MAIN OUTCOME MEASURE

The primary outcome measure was the proportion of PP orders prescribed for patients older versus younger than age 65. The secondary outcomes were to identify other variables occurring in higher proportions among patients who were prescribed PP versus HC.

RESULTS

Of the 7,910 patients reviewed, 7,295 patients 92.2% were prescribed HC and 615 (7.8%) were prescribed PP. In a random sample of 1,065 patients, the prescribing pattern of PP for subjects > or =65 (221/615, 35.9%), was significantly higher than for HC (128/450, 28.4%), P = 0.0122. In a random selection of the larger sample, there were 44/108 (40.7%) in the PP group and 22/120 subjects (18.3%) > or =65 in the HC group (P = 0.0003). Among PP users, there was a higher percentage of females (P = 0.0150), more subjects with narcotic allergies (P < 0.0001), and more subjects with a history of fractures (P = 0.0232).

CONCLUSIONS

Compared with nationally reported data, the rate of PP prescribing is relatively low. However, despite the recommendation to avoid the use of PP in elderly patients, its use occurs in a higher proportion of patients age 65 years or older than in younger patients. Studies evaluating the prescribing rates of potentially inappropriate medications should be put in context by comparing reported data with that of a younger cohort.