Gabapentin reduces preoperative anxiety and pain catastrophizing in highly anxious patients prior to major surgery: a blinded randomized placebo-controlled trial

Efficacy and Safety of Anxiolytics in Mohs Micrographic Surgery: A Randomized, Double-Blinded, Placebo-Controlled Trial

BACKGROUND

Patient anxiety can complicate surgical outcomes by elevating blood pressure, increasing the need for postoperative pain management, and reducing overall patient satisfaction. Despite the use of anxiolytic medications in outpatient procedures, there is limited comparative evidence on the efficacy and safety of these agents in Mohs micrographic surgery.

OBJECTIVE

To compare the effectiveness and safety of different preprocedural anxiolytic agents in Mohs surgery on perioperative patient anxiety and patient satisfaction.

MATERIALS AND METHODS

A double-blinded, randomized, placebo-controlled trial was conducted of 6 different preprocedural anxiolytic agents (lorazepam, diazepam, alprazolam, gabapentin, pregabalin, and melatonin) in 350 patients undergoing Mohs surgery. Anxiety and vital signs were recorded.

RESULTS

Diazepam demonstrated a statistically significant, sustained reduction in anxiety levels compared with placebo ( p = .03). Gabapentin significantly reduced early anxiety ( p = .02). Alprazolam showed a trend to early anxiety reduction ( p = .08). Lorazepam ( p = .73), pregabalin ( p = .53), and melatonin ( p = .24) failed to reduce patient anxiety compared with placebo at any time point. No anxiolytic significantly impacted any patient vital sign or cognition.

CONCLUSION

Although short-acting benzodiazepines and gamma-aminobutyric acid medications may have transient anxiolytic effects, a single oral dose of 5 mg of diazepam can provide a sustained anxiolytic effect in Mohs surgery, with excellent patient safety.

Pain, Anxiety, and the Continuous Use of Opioids and Benzodiazepines in Trauma Intensive Care Unit Survivors: An Exploratory Study

OBJECTIVE

To evaluate at-home opioid and benzodiazepine use, the degrees of pain and anxiety, and the incidence of probable withdrawal in post-discharge Trauma Intensive Care Unit (TICU) survivors.

METHODS

This was an exploratory study of post-TICU survivors who had participated in a previous study of opioid and benzodiazepine withdrawal. We surveyed survivors by telephone asking for retrospective information (during their first 4-months postdischarge- Time 1) and current information (around 2-years post-discharge- Time 2).

RESULTS

A mostly male (82%), young (median 38 years [IQR, 28-52]) sample of 27 TICU survivors reported using opioids (56%) at Time 1 for a median of 30 (IQR,14-90) days. Twelve percent of 26 survivors were still using opioids at Time 2. Sixty percent of the survivors had pain during Time 1, a median pain score of 6 (IQR, 5-8) on a 0-10 numeric rating scale (NRS).; 57% had pain at Time 2, median NRS score=6 (IQR, 4-7). Sixty-five percent of survivors had anxiety during Time 1, NRS median=7 (IQR, 5-9); 50% had anxiety at Time 2, NRS median= 6 (IQR, 3-7). At Time 1, 26% used prescribed benzodiazepines, and 12% used benzodiazepines at Time 2. Five and one of the 27 patients reported symptoms of opioid or benzodiazepine withdrawal, respectively, upon discontinuation or weaning.

CONCLUSION

Many TICU survivors had discontinued opioid/benzodiazepine prescriptions by 4-months post discharge while half reporting pain/anxiety for up to 2-years. Investigating the effects of acute-to-chronic pain in ICU survivors and gaining a better understanding of the mechanisms of prolonged opioid use are warranted.

Factors Related to Neuropathic Pain following Lower Extremity Amputation

BACKGROUND

Lower extremity amputations are common, and postoperative neuropathic pain (phantom limb pain or symptomatic neuroma) is frequently reported. The use of active treatment of the nerve end has been shown to reduce pain but requires additional resources and should therefore be performed primarily in high-risk patients. The aim of this study was to identify the factors associated with the development of neuropathic pain following above-the-knee amputation, knee disarticulation, or below-the-knee amputation.

METHODS

Retrospectively, 1565 patients with an average follow-up of 4.3 years who underwent a primary above-the-knee amputation, knee disarticulation, or below-the-knee amputation were identified. Amputation levels for above-the-knee amputations and knee disarticulations were combined as proximal amputation level, with below-the-knee amputations being performed in 61 percent of patients. The primary outcome was neuropathic pain (i.e., phantom limb pain or symptomatic neuroma) based on medical chart review. Multivariable logistic regression was performed to identify independent factors associated with neuropathic pain.

RESULTS

Postoperative neuropathic pain was present in 584 patients (37 percent), with phantom limb pain occurring in 34 percent of patients and symptomatic neuromas occurring in 3.8 percent of patients. Proximal amputation level, normal creatinine levels, and a history of psychiatric disease were associated with neuropathic pain. Diabetes, hypothyroidism, and older age were associated with lower odds of developing neuropathic pain.

CONCLUSIONS

Neuropathic pain following lower extremity amputation is common. Factors influencing nerve regeneration, either increasing (proximal amputations and younger age) or decreasing (diabetes, hypothyroidism, and chronic kidney disease) it, play a role in the development of postamputation neuropathic pain.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Long-Term Opioid Use Following Surgery for Symptomatic Neuroma

BACKGROUND

 Identifying patients at risk for prolonged opioid use following surgery for symptomatic neuroma would be beneficial for perioperative management. The aim of this study is to identify the factors associated with postoperative opioid use of >4 weeks in patients undergoing neuroma surgery.

METHODS

 After retrospective identification, 77 patients who underwent surgery for symptomatic neuroma of the upper or lower extremity were enrolled. Patients completed the Patient-Reported Outcomes Measurement Information System (PROMIS) depression, Numeric Rating Scale (NRS) pain score, and a custom medication questionnaire at a median of 9.7 years (range: 2.5-16.8 years) following surgery. Neuroma excision followed by nerve implantation (n = 39, 51%), nerve reconstruction/repair (n = 18, 23%), and excision alone (n = 16, 21%) were the most common surgical treatments.

RESULTS

 Overall, 27% (n = 21) of patients reported opioid use of more than 4 weeks postoperatively. Twenty-three patients (30%) reported preoperative opioid use of which 11 (48%) did not report opioid use for >4 weeks, postoperatively. In multivariable logistic regression, preoperative opioid use was independently associated with opioid use of >4 weeks, postoperatively (odds ratio [OR] = 4.4, 95% confidence interval [CI]: 1.36-14.3, p = 0.013).

CONCLUSION

 Neuroma surgery reduces opioid use in many patients but patients who are taking opioids preoperatively are at risk for longer opioid use. Almost one-third of patients reported opioid use longer than 4 weeks, postoperatively.

Hemodynamic, Echocardiographic, and Sedative Effects of Oral Gabapentin in Healthy Cats

The study objective was to evaluate sedative, hemodynamic, and echocardiographic effects of cats receiving single-dose, oral gabapentin. A prospective, double-blinded, placebo-controlled, crossover study was conducted with 10 client-owned cats. Vital parameters, physical exam, blood pressure, echocardiography, and sedation scoring were performed at each visit within 2 hr of receiving either a placebo or gabapentin capsule. Vital parameters, blood pressure recordings, and echocardiographic measurements were compared between baseline, gabapentin, and placebo; interobserver agreement for sedation scoring and correlation between variables were also evaluated. Seven of 10 cats exhibited mild sedation within 120 min after receiving gabapentin, and no adverse events occurred. Significant differences were detected with two-dimensional fractional shortening (P = .022), left ventricular internal diameter in systole using M-mode (P = .014), and left atrial volume (P < .0001). Interobserver agreement for sedation scoring was near-perfect (κ = 0.84). No significant correlation was found for gabapentin dosage and sedation score. Single-dose oral gabapentin is well tolerated in healthy cats and produces a modest decrease in several echocardiographic parameters of systolic function; however, all affected variables remained within established reference ranges. These results suggest gabapentin may be an appropriate sedative to administer before echocardiography in cats necessitating mild sedation.

Perioperative Gabapentin in Pediatric Thoracic Surgery Patients-Randomized, Placebo-Controlled, Phase 4 Trial

OBJECTIVE

To determine whether the use of perioperative gabapentin reduces postoperative pain and anxiety, decreases ropivacaine consumption and side effects, and improves patient satisfaction.

DESIGN

Randomized, placebo-controlled, phase 4 trial.

BLINDING

Participants, care providers, investigators, data analysts.

SETTING

Department of Thoracic Surgery of the Institute of Tuberculosis and Lung Disease, Rabka Zdrój Branch, Poland.

SUBJECTS

Forty patients undergoing the Ravitch procedure.

METHODS

Patients aged nine to 17 years were randomized into a gabapentin (preoperative 15 mg/kg, treatment) or placebo group. Postoperative analgesia included gabapentin (7.5 mg/kg) or placebo two times per day for three days, epidural ropivacaine + fentanyl, paracetamol, nonsteroidal anti-inflammatory drugs, and metamizol as a "rescue drug." Pain, anxiety, analgesic consumption, side effects, and patient satisfaction were recorded.

RESULTS

There was no statistically significant difference in median pain scores (numerical rating scale < 1/10) or incidence of adverse side effects between the gabapentin group (N = 20) and the placebo group (N = 20). Postoperative anxiety scores were significantly lower than before surgery in the gabapentin group (6 [4-8] vs 7 [6-8.5], P < 0.01) and remained unchanged in the placebo group (6 [5-6.5] vs 6 [5-7], P = 0.07). Gabapentin-treated patients received a lower number of doses of ondansetron when compared with the placebo group (6 [5-6] vs 7 [6-9], P = 0.02). A significant negative association was found between patient satisfaction and postoperative state anxiety in the gabapentin group (R = -0.51, P = 0.02).

CONCLUSIONS

Perioperative administration of gabapentin resulted in a decrease of postoperative anxiety in pediatric patients undergoing the Ravitch procedure.

The Clinical Difference between Gabapentin and Pregabalin: Data from a Pilot Comparative Trial

BACKGROUND

Similar anticonvulsants, such as gabapentin and pregabalin are recommended in neuropathic pain management, however little is known about their clinical differences in cases of low back pain. This paper aims to highlight some of the possible clinical differences between gabapentin and pregabalin in low back pain.

METHODS

Patients with moderate to severe low back pain were recruited. Eligible patients were randomised to receive either pregabalin (300 mg/day)or gabapentin (800 mg/day) for six weeks. The primary outcome measure was pain intensity according to the Visual Analogue Score (VAS) at baseline and at six weeks. The secondary outcome measures were: anxiety, insomnia, fatigue and the self-rated (GCI), measured at baseline, second, fourth, and the sixth week.

RESULTS

A total of 64 patients, pregabalin group (n=28), gabapentin group (n=36) completed the study. While pregabalin group showed a significantly lower pain score (p=0.039). The gabapentin group showed significant improvement in anxiety (p=0.001), insomnia (p=0.001), general fatigue (p=0.009), physical fatigue (p=0.001), reduce activity (p=0.001), and mental fatigue (p=0.014) higher than that of pregabalin. No difference in (GCI) was seen at six weeks.

CONCLUSION

This is the first trial aimed at comparing gabapentin with pregabalin in NLBP. Although the results are preliminary, in our pilot study pregabalin was found to be superior in pain reduction, gabapentin demonstrated better effect on anxiety, insomnia and fatigue symptoms. The results are preliminary and studies with a larger sample size are still required.

GPR30 receptor promotes preoperative anxiety-induced postoperative hyperalgesia by up-regulating GABAA-α4β1δ subunits in periaqueductal gray in female rats

BACKGROUND

G-protein coupled estrogen receptor 30 (GPR30) was proved the specific estrogen receptor relating to mechanical hyperalgesia. Studies have shown that the GABA_A receptor subunits α4, β1, and δ in the periaqueductal gray (PAG) neurons promote the descending facilitation system. This study inquired into whether and how GPR30 and GABA_A-α4β1δ in the PAG promote preoperative anxiety-induced postoperative hyperalgesia in female rats.

METHODS

All the female rats were subjected to the single prolonged stress (SPS) to stimulate preoperative anxiety. Subsequently, mechanical allodynia was evaluated before and after the incision, based on the paw withdrawal mechanical threshold (PWMT). The selective GPR30 agonist G1 and antagonist G15 were locally microinjected into the PAG. The expression of GPR30, protein kinase A (PKA), and GABA_A receptor subunits α4, β1, and δ in the PAG neurons were detected using western blotting and immunofluorescence.

RESULTS

Behavioral testing revealed that Group S and Group I decreased the nociceptive threshold levels of PWMT in female rats. PWMT in Group S + I decreased more than that of Group S and Group I. Further, results of western blotting showed the expression of GPR30, PKA, and GABA_A α4, β1, and δ subunits significantly up-regulated in Group S + I, and immunofluorescence indicated that the neurons of PAG in Group S + I appeared simultaneously immunopositive for GPR30 and GABA_A α4, β1, and δ receptors. After microinjection of G1 into the PAG, female rats with plantar incision continued to exhibit significant hyperalgesia until postoperative 48 h. On the other hand, microinjection of G15 with SPS and plantar incision procedure relieved postoperative hyperalgesia in female rats. Western blotting demonstrated that intra-PAG injection of G15 markedly decreased the GPR30, PKA, and GABA_A α4, β1, and δ levels in Group G15 + I.

CONCLUSIONS

Our results indicate that the GPR30-PKA-GABA_Aα4β1δ pathway in the PAG promotes preoperative anxiety-induced postoperative hyperalgesia in female rats. This mechanism might be a potential novel therapeutic target for hyperalgesia in females.

Gabapentin increases expression of δ subunit-containing GABAA receptors

BACKGROUND

Gabapentin is a structural analog of the inhibitory neurotransmitter γ-aminobutyric acid (GABA). Its anticonvulsant, analgesic and anxiolytic properties suggest that it increases GABAergic inhibition; however, the molecular basis for these effects is unknown as gabapentin does not directly modify GABA type A (GABA_A) receptor function, nor does it modify synaptic inhibition. Here, we postulated that gabapentin increases expression of δ subunit-containing GABA_A (δGABA_A) receptors that generate a tonic inhibitory conductance in multiple brain regions including the cerebellum and hippocampus.

METHODS

Cell-surface biotinylation, Western blotting, electrophysiologic recordings, behavioral assays, high-performance liquid chromatography and gas chromatography-mass spectrometry studies were performed using mouse models.

FINDINGS

Gabapentin enhanced expression of δGABA_A receptors and increased a tonic inhibitory conductance in neurons. This increased expression likely contributes to GABAergic effects as gabapentin caused ataxia and anxiolysis in wild-type mice but not δ subunit null-mutant mice. In contrast, the antinociceptive properties of gabapentin were observed in both genotypes. Levels of GABA_A receptor agonists and neurosteroids in the brain were not altered by gabapentin.

INTERPRETATION

These results provide compelling evidence to account for the GABAergic properties of gabapentin. Since reduced expression of δGABA_A receptor occurs in several disorders, gabapentin may have much broader therapeutic applications than is currently recognized. FUND: Supported by a Foundation Grant (FDN-154312) from the Canadian Institutes of Health Research (to B.A.O.); a NSERC Discovery Grant (RGPIN-2016-05538), a Canada Research Chair in Sensory Plasticity and Reconsolidation, and funding from the University of Toronto Centre for the Study of Pain (to R.P.B.).

Use of Gabapentin in the Treatment of Substance Use and Psychiatric Disorders: A Systematic Review

Objective: Gabapentin (GBP) is an anticonvulsant medication that is also used to treat restless legs syndrome (RLS) and posttherapeutic neuralgia. GBP is commonly prescribed off-label for psychiatric disorders despite the lack of strong evidence. However, there is growing evidence that GBP may be effective and clinically beneficial in both psychiatric disorders and substance use disorders. This review aimed to perform a systematic analysis of peer-reviewed published literature on the efficacy of GBP in the treatment of psychiatric disorders and substance use disorders. Methods: This review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The PubMed and Ovid MEDLINE literature databases were screened and filtered by using specific search terms and inclusion/exclusion criteria. The full texts of selected studies were subsequently retrieved and reviewed. The search terms generated 2,604 results from the databases. After excluding all duplicates, 1,088 citations were left. Thereafter, we applied inclusion and exclusion criteria; a total of 54 papers were retained for detailed review. Results: This literature review concludes that GBP appears to be effective in the treatment of various forms of anxiety disorders. It shows some effectiveness in bipolar disorder as an adjunctive therapeutic agent, while the evidence for monotherapy is inconclusive. In substance use disorders, GBP is effective for acute alcohol withdrawal syndrome (AWS) with mild to moderate severity; it reduces cravings, improves the rate of abstinence, and delays return to heavy drinking. GBP may have some therapeutic potential in the treatment of opioid addiction and cannabis dependence, but there is limited evidence to support its use. No significant benefit of GBP has been conclusively observed in the treatment of OCD, PTSD, depression, or cocaine and amphetamine abuse. Conclusion: GBP appears to be effective in some forms of anxiety disorders such as preoperative anxiety, anxiety in breast cancer survivors, and social phobia. GBP has shown to be safe and effective in the treatment of alcohol dependence. However, the literature suggests that GBP is effective as an adjunctive medication rather than a monotherapy. More clinical trials with larger patient populations are needed to support gabapentin's off-label use in psychiatric disorders and substance use disorders. It is worth noting that numerous clinical studies that are discussed in this review are open-label trials, which are inherently less rigorously analyzed. Therefore, more extensive investigations are required to examine not only the efficacy of GBP, but also its safety and tolerance.

Efficacy of Non-pharmacological Methods of Pain Management in Children Undergoing Venipuncture in a Pediatric Outpatient Clinic: A Randomized Controlled Trial of Audiovisual Distraction and External Cold and Vibration

PURPOSE

Venipuncture generates anxiety and pain in children. The primary aim of the study was to evaluate two non-pharmacological techniques, vibration combined with cryotherapeutic topical analgesia by means of the Buzzy® device and animated cartoons, in terms of pain and anxiety relief during venipuncture in children.

DESIGNS AND METHODS

150 children undergoing venipuncture were randomized into four groups: the 'no method' group, the Buzzy® device group, the animated cartoon group and the combination of Buzzy® and an animated cartoon group. Children's pain and anxiety levels along with parents' and nurses' anxiety levels were evaluated by means of validated grading scales.

RESULTS

Overall children's pain increased less in the non-pharmacological intervention groups as compared to the group without intervention. Notably, the difference was statistically significant in the animated cartoon group for children's perception of pain. Children's anxiety and parents' anxiety decreased more in non-pharmacological interventions groups as compared to the group without intervention.

CONCLUSIONS

The study showed the effectiveness of non-pharmacological methods of pain management during venipuncture. Notably, distraction with animated cartoons was superior in terms of children's perception of pain when compared to Buzzy®, and to the combination of cartoons and Buzzy®. Buzzy® was significantly effective at the secondary analysis for children younger than 9. Children's and parents' anxiety is decreased by non-pharmacological methods. Furthermore, nurses' involvement in pediatric care can be enhanced.

PRACTICE IMPLICATIONS

Non-pharmacological methods of pain management during venipuncture represent an easy way to achieve an increased level of compliance among children and parents.

Pharmacological challenge studies with acute psychosocial stress

Chronic stress is known to affect many psychiatric disorders, and studies of responses to acute stress may reveal processes that ultimately lead to maladaptive responses to chronic stress. Many studies have used simulated public speaking tasks to induce stress in the laboratory and, of interest to this review, the tasks have been used to assess the effects of both therapeutic and nonmedical drugs on stress reactivity. Here we review 38 studies that examined effects of single doses of drugs on subjective, cardiovascular and hormonal responses to an acute social stressor in healthy volunteers. Most studies have used the Trier Social Stress Test (TSST), or variations on it involving public speaking or mental arithmetic. Pharmacological studies with the TSST (ph-TSST) have been conducted for three main reasons: i) to determine the clinical effectiveness of psychiatric medications to reduce stress responses, ii) to investigate the neurochemical mechanisms involved in the stress response, and iii) to determine whether drugs of abuse relieve, or occasionally worsen, responses to acute stress. The review indicates that standard anxiolytic medications consistently reduce subjective responses to the TSST, whereas single doses of antidepressants produce mixed effects. Mechanistic studies indicate that several neurotransmitter systems are involved in the stress response, including serotonin, norepinephrine, GABA, glutamate, opioids, and endocannabinoids. Among drugs of abuse, alcohol and cannabinoids exert some stress-dampening effects, whereas caffeine, nicotine, and amphetamines tend to increase stress responses. Comparing outcome measures of the responses to stress, subjective ratings of anxiety are among the most sensitive indices of the stress response, with cortisol levels second and cardiovascular responses least sensitive. We conclude that the TSST is a valuable tool to study the clinical effectiveness of medications for stress-related disorders, and that it is important to use standardized procedures to enable comparisons across studies.

Dose-related beneficial and harmful effects of gabapentin in postoperative pain management - post hoc analyses from a systematic review with meta-analyses and trial sequential analyses

Background

During the last 15 years, gabapentin has become an established component of postoperative pain treatment. Gabapentin has been employed in a wide range of doses, but little is known about the optimal dose, providing the best balance between benefit and harm. This systematic review with meta-analyses aimed to explore the beneficial and harmful effects of various doses of gabapentin administered to surgical patients.

Materials and methods

Data in this paper were derived from an original review, and the subgroup analyses were predefined in an International Prospective Register of Systematic Reviews published protocol: PROSPERO (ID: CRD42013006538). The methods followed Cochrane guidelines. The Cochrane Library’s CENTRAL, PubMed, EMBASE, Science Citation Index Expanded, Google Scholar, and FDA database were searched for relevant trials. Randomized clinical trials comparing gabapentin versus placebo were included. Four different dose intervals were investigated: 0–350, 351–700, 701–1050, and >1050 mg. Primary co-outcomes were 24-hour morphine consumption and serious adverse events (SAEs), with emphasis put on trials with low risk of bias.

Results

One hundred and twenty-two randomized clinical trials, with 8466 patients, were included. Sixteen were overall low risk of bias. No consistent increase in morphine-sparing effect was observed with increasing doses of gabapentin from the trials with low risk of bias. Analyzing all trials, the smallest and the highest dose subgroups demonstrated numerically the most prominent reduction in morphine consumption. Twenty-seven trials reported 72 SAEs, of which 83% were reported in the >1050 mg subgroup. No systematic increase in SAEs was observed with increasing doses of gabapentin.

Conclusion

Data were sparse, and the small number of trials with low risk of bias is a major limitation for firm conclusions. Taking these limitations into account, we were not able to demonstrate a clear relationship between the dosage of gabapentin and opioid-sparing or harmful effects. These subgroup analyses are exploratory and hypothesis-generating for future trialists.

Gabapentin for post-operative pain management - a systematic review with meta-analyses and trial sequential analyses

BACKGROUND

Perioperative pain treatment often consist of combinations of non-opioid and opioid analgesics, 'multimodal analgesia', in which gabapentin is currently used. The aim was to document beneficial and harmful effects of perioperative gabapentin treatment.

METHODS

Randomized clinical trials comparing gabapentin vs. placebo or active placebo in adult surgical patients receiving gabapentin perioperatively were included. This review was conducted using Cochrane standards, trial sequential analysis (TSA), and Grading of Recommendations Assessment, Development, and Evaluation (GRADE). The primary outcomes were 24-h opioid consumption and incidence of serious adverse events (SAE).

RESULTS

One hundred and thirty-two trials with 9498 patients were included. Thirteen trials with low risk of bias reported a reduction in 24-h opioid consumption of 3.1 mg [0.5, 5.6] [corrected]. In the analysis of gabapentin as add-on analgesic to another non-opioid analgesic regimen found a mean reduction in 24-h morphine consumption of 1.2 mg [-0.3, 2.6; TSA-adjusted CI: -0.3, 2.6] in trials with low risk of bias. [corrected]. Nine trials with low risk of bias reported a risk ratio of SAEs of 1.61 [0.91; 2.86; TSA-adjusted CI: 0.57, 4.57].

CONCLUSION

Based on GRADE assessment of the primary outcomes in trials with low risk of bias, the results are low or very low quality of evidence due to imprecision, inconsistency, and in some outcomes indirectness. Firm evidence for use of gabapentin is lacking as clinically relevant beneficial effect of gabapentin may be absent and harm is imminent, especially when added to multimodal analgesia.

Moving without moving: immediate management following lumbar spine surgery using a graded motor imagery approach: a case report

Representational body maps are dynamically maintained in the brain and negatively influenced by neglect, decreased movement and pain. Graded motor imagery (GMI) utilizing various tactile and cognitive processes has shown efficacy in decreasing pain, disability and movement restrictions in musculoskeletal pain. Limited information is known about the cortical changes patients undergo during lumbar surgery (LS), let alone the therapeutic effect of GMI for LS. A 56-year-old patient underwent LS for low back pain, leg pain and progressive neurological deficit. Twenty-four hours prior to and 48 h after LS various psychometric, physical movement and tactile acuity measurements were recorded. Apart from predictable postoperative increases in pain, fear-avoidance, disability and movement-restrictions, pressure pain thresholds (PPT), two-point discrimination (TPD) and tactile acuity was greatly reduced. The patient underwent six physiotherapy (PT) treatments receiving a GMI program aimed at restoring the PPT, TPD and tactile acuity. The results revealed that GMI techniques applied to a patient immediately after LS caused marked improvements in movement (flexion average improvement/session 3.3 cm; straight leg raise average 8.3°/session) and an immediate hypoalgesic effect. GMI may provide PT with a non-threatening therapeutic treatment for the acute LS patient and establish a new role for PT in acute LS patients.

The Psychopharmacology Algorithm Project at the Harvard South Shore Program: An Algorithm for Generalized Anxiety Disorder

This revision of previous algorithms for the pharmacotherapy of generalized anxiety disorder was developed by the Psychopharmacology Algorithm Project at the Harvard South Shore Program. Algorithms from 1999 and 2010 and associated references were reevaluated. Newer studies and reviews published from 2008-14 were obtained from PubMed and analyzed with a focus on their potential to justify changes in the recommendations. Exceptions to the main algorithm for special patient populations, such as women of childbearing potential, pregnant women, the elderly, and those with common medical and psychiatric comorbidities, were considered. Selective serotonin reuptake inhibitors (SSRIs) are still the basic first-line medication. Early alternatives include duloxetine, buspirone, hydroxyzine, pregabalin, or bupropion, in that order. If response is inadequate, then the second recommendation is to try a different SSRI. Additional alternatives now include benzodiazepines, venlafaxine, kava, and agomelatine. If the response to the second SSRI is unsatisfactory, then the recommendation is to try a serotonin-norepinephrine reuptake inhibitor (SNRI). Other alternatives to SSRIs and SNRIs for treatment-resistant or treatment-intolerant patients include tricyclic antidepressants, second-generation antipsychotics, and valproate. This revision of the GAD algorithm responds to issues raised by new treatments under development (such as pregabalin) and organizes the evidence systematically for practical clinical application.

Effect of gabapentin pretreatment on myoclonus after etomidate: a randomized, double-blind, placebo-controlled study

AIM

To evaluate the effects of three different doses of gabapentin pretreatment on the incidence and severity of myoclonic movements linked to etomidate injection.

METHOD

One hundered patients, between 18 and 60 years of age and risk category American Society of Anesthesiologists I-II, with planned elective surgery under general anesthetic were included in the study. The patients were randomly divided into four groups and 2h before the operation were given oral capsules of placebo (Group P, n=25), 400mg gabapentin (Group G400, n=25), 800mg gabapentin (Group G800, n=25) or 1200mg gabapentin (Group G1200, n=25). Side effects before the operation were recorded. After preoxygenation for anesthesia induction 0.3mgkg(-1) etomidate was administered for 10s. A single anesthetist with no knowledge of the study medication evaluated sedation and myoclonic movements on a scale between 0 and 3. Two minutes after induction, 2μgkg(-1) fentanyl and 0.8mgkg(-1) rocuronium were administered for tracheal intubation.

RESULTS

Demographic data were similar. Incidence and severity of myoclonus in Group G1200 and Group G800 were significantly lower than in Group P; sedation incidence and level were appreciably higher compared to Group P and Group G400. While there was no difference in the incidence of myoclonus between Group P and Group G400, the severity of myoclonus in Group G400 was lower than in the placebo group. In the two-hour period before induction other than sedation none of the side effects related to gabapentin were observed in any patient.

CONCLUSION

Pretreatment with 800mg and 1200mg gabapentin 2h before the operation increased the level of sedation and reduced the incidence and severity of myoclonic movements due to etomidate.

Caring for the surgically anxious patient: a review of the interventions and a guide to optimizing surgical outcomes

BACKGROUND

Preoperative surgical anxiety is an unpleasant and common reaction exhibited by patients who are scheduled for surgical procedures. Beyond emotional effects on the patient, it can also have negative repercussions on the surgery including longer hospital stays and poorer outcomes. Given the widespread impacts of preoperative anxiety, it is critical for surgeons to gain a better understanding of how to identify and reduce surgical anxiety in their patients.

DATA SOURCES

This study used the PubMed database to review the current literature to evaluate screening tools and interventions for surgically anxious patients.

CONCLUSIONS

Psychiatric anxiety surveys are currently the most appropriate form of assessment for surgical anxiety. Patient education is important for preventing and reducing anxiety levels in patients. Both nonpharmacological and pharmacological interventions have been shown to be effective in reducing patient anxiety and treatment should be based on patient preference, resources available, and the surgeon's experience.

Can Preoperative Psychological Assessment Predict Outcomes After Temporomandibular Joint Arthroscopy?

PURPOSE

Psychological assessment has been used successfully to predict patient outcomes after cardiothoracic and bariatric surgery. The purpose of this study was to determine whether preoperative psychological assessment could be used to predict patient outcomes after temporomandibular joint arthroscopy.

MATERIALS AND METHODS

Consecutive patients with temporomandibular dysfunction (TMD) who could benefit from arthroscopy were enrolled in a prospective cohort study. All patients completed the Millon Behavior Medicine Diagnostic survey before surgery. The primary predictor variable was the preoperative psychological scores. The primary outcome variable was the difference in pain between the pre- and postoperative periods. The Spearman rank correlation coefficient and the Pearson product-moment correlation were used to determine the association between psychological factors and change in pain. Univariable and multivariable analyses were performed using a mixed-effects linear model and multiple linear regression. A P value of .05 was considered significant.

RESULTS

Eighty-six patients were enrolled in the study. Seventy-five patients completed the study and were included in the final analyses. The mean change in visual analog scale (VAS) pain score 1 month after arthroscopy was -15.4 points (95% confidence interval, -6.0 to -24.7; P < .001). Jaw function also improved after surgery (P < .001). No association between change in VAS pain score and each of the 5 preoperative psychological factors was identified with univariable correlation analyses. Multivariable analyses identified that a greater pain decrease was associated with a longer duration of preoperative symptoms (P = .054) and lower chronic anxiety (P = .064).

CONCLUSIONS

This study has identified a weak association between chronic anxiety and the magnitude of pain decrease after arthroscopy for TMD. Further studies are needed to clarify the role of chronic anxiety in the outcome after surgical procedures for the treatment of TMD.

Premedication with gabapentin, alprazolam or a placebo for abdominal hysterectomy: Effect on pre-operative anxiety, post-operative pain and morphine consumption

Background and Aims:

Utility of gabapentin for pre-operative anxiolysis as compared to commonly administered alprazolam is not evident. The aim of the present study was to compare the effects of pre-operative oral gabapentin 600 mg, alprazolam 0.5 mg or a placebo on pre-operative anxiety along with post-operative pain and morphine consumption.

Methods:

Seventy five patients scheduled for abdominal hysterectomy under general anaesthesia were included. Groups gabapentin, alprazolam and placebo, received oral gabapentin 600 mg, alprazolam 0.5 mg and one capsule of oral B-complex forte with Vitamin C respectively, on the night prior to surgery and 2 h prior to surgery. Visual analogue scale (VAS) was used to measure the anxiety and post-operative pain. All patients received patient-controlled analgesia. Statistical tests used were Kruskal–Wallis test, Wilcoxon signed rank test and one-way ANOVA.

Results:

Alprazolam provided significant anxiolysis (median [interquartile range] baseline VAS score 35 [15.5, 52] to 20 [6.5, 34.5] after drug administration; P = 0.007). Gabapentin did not provide significant decrease in anxiety (median [interquartile range] VAS score 21 [7.5, 41] to 20 [6.5, 34.5]; P = 0.782). First analgesic request time (median [interquartile range in minutes]) was longer in group gabapentin (17.5 [10, 41.25]) compared to group placebo (10 [5, 15]) (P = 0.019) but comparable to that in group alprazolam (15 [10, 30]). Cumulative morphine consumption at different time periods and total morphine consumption (mean [standard deviation]) at the end of study period (38.65 [18.04], 39.91 [15.73], 44.29 [16.02] mg in group gabapentin, alprazolam and placebo respectively) were comparable.

Conclusion:

Gabapentin 600 mg does not have significant anxiolytic effect compared to alprazolam 0.5 mg. Alprazolam 0.5 mg was found to be an effective anxiolytic in the pre-operative period. Neither alprazolam nor gabapentin, when compared to placebo showed any opioid sparing effects post-operatively.

Gabapentin prophylaxis for postoperative nausea and vomiting in abdominal surgeries: a quantitative analysis of evidence from randomized controlled clinical trials

INTRODUCTION

Postoperative nausea and vomiting (PONV) is frequently encountered in the surgical recovery room. Abdominal surgery is one important risk factor for increased incidence of PONV. Gabapentin, an anticonvulsant with known postoperative analgesic properties, has shown some activity against PONV. Results from clinical trials evaluating the anti-emetic efficacy of gabapentin are conflicting. The present meta-analysis was performed to examine this issue.

METHODS

Seventeen randomized placebo-controlled trials reporting PONV with preoperative gabapentin administration in patients undergoing abdominal surgery were included for analysis. Outcomes evaluated were nausea, vomiting, composite PONV and the use of rescue anti-emetic medication in the postoperative period.

RESULTS

The pooled relative risk (RR), estimated using the random effects model of the metafor package for R, was 0.76 (95% CI 0.58-0.98) for nausea, 0.62 (0.45-0.85) for vomiting, 0.71 (0.39-1.28) for data represented as composite PONV (possibly biased by a single study, as observed in the sensitivity analysis), and 0.6 (0.41-0.89) for rescue anti-emetic use. There was a significant RR reduction for nausea and vomiting when propofol was not used as induction and/or maintenance for anaesthesia. In the abdominal hysterectomy subgroup, there was a significant RR reduction for vomiting but not for nausea.

DISCUSSION

The present analysis provides evidence supporting preoperative gabapentin as a pharmacotherapy for prevention of PONV in patients undergoing abdominal surgeries. Future studies comparing preoperative gabapentin with 5HT3 antagonists are needed to precisely define its role in PONV.

Pain catastrophizing as a risk factor for chronic pain after total knee arthroplasty: a systematic review

BACKGROUND

Total knee arthroplasty (TKA) is a common and costly surgical procedure. Despite high success rates, many TKA patients develop chronic pain in the months and years following surgery, constituting a public health burden. Pain catastrophizing is a construct that reflects anxious preoccupation with pain, inability to inhibit pain-related fears, amplification of the significance of pain vis-à-vis health implications, and a sense of helplessness regarding pain. Recent research suggests that it may be an important risk factor for untoward TKA outcomes. To clarify this impact, we systematically reviewed the literature to date on pain catastrophizing as a prospective predictor of chronic pain following TKA.

METHODS

We searched MEDLINE, EMBASE, and PsycINFO databases to identify articles related to pain catastrophizing, TKA, risk models, and chronic pain. We reviewed titles and abstracts to identify original research articles that met our specified inclusion criteria. Included articles were then rated for methodological quality. including methodological quality. Due to heterogeneity in follow-up, analyses, and outcomes reported across studies, a quantitative meta-analysis could not be performed.

RESULTS

We identified six prospective longitudinal studies with small-to-mid-sized samples that met the inclusion criteria. Despite considerable variability in reported pain outcomes, pain catastrophizing was identified as a significant predictor of chronic pain persisting ≥3 months following TKA in five of the studies assessed. Limitations of studies included lack of large-scale data, absence of standardized pain measurements, inadequate multivariate adjustment, such as failure to control for analgesic use and other relevant covariates, and failure to report non-significant parameter estimates.

CONCLUSION

This study provides moderate-level evidence for pain catastrophizing as an independent predictor of chronic pain post-TKA. Directions for future research include larger, well-controlled studies with standard pain outcomes, identification of clinically-relevant catastrophizing cut-offs that predict pain outcomes, investigation of other psychosocial risk factors, and assessment of interventions aimed to reduce pain catastrophizing on chronic pain outcomes following TKA surgery.

The distinctive significance of analgesic drugs and olfactory stimulants on learned pain in mice

Chronic pain is often intractable to analgesics, and in animals it involves a conditioned nociceptive response (CR) - learned pain. The neural pathways of nociception and olfactory function in the brain overlap. The influence of olfactory stimuli on acute pain has been studied in some depth in animal and human models, but the influence of olfactory stimuli on learned pain has not been understood. We examined the effects of analgesic drugs and olfactory stimulants (preferred or repellent odor) on acute pain, the unconditioned nociceptive response (UCR) and the CR in mice. The CR was provoked by repeated injection of formalin into the hind-paw in animals in the same context, which elicited the typical pain behaviors of paw licking (including biting). The analgesic drugs acetaminophen, fentanyl, gabapentin and fluvoxamine diminished the UCR but did not affect the CR. In contrast, the preferred odor reduced both the UCR and the CR. Our findings suggest that, like chronic pain, the CR is resistant to analgesic drugs and that preferred odor suppress the neural pathways that mediate the CR of pain perception.

Acute pain management

This article updates acute pain management in ambulatory surgery and proposes a practical three-step approach for reducing the impact and incidence of uncontrolled surgical pain. By identifying at-risk patients, implementing multimodal analgesia, and intervening promptly with rescue therapies, the anesthesiologist may improve outcomes, reduce cost, and optimize the patient's experience and quality of recovery.

Predictors of postoperative pain trajectories in adolescent idiopathic scoliosis

STUDY DESIGN

Prospective observational study.

OBJECTIVE

To determine the typical trajectory of pain during the first 6 months after spinal fusion surgery for adolescent idiopathic scoliosis (AIS) and the extent to which certain demographic, medical, and psychological variables modify this trajectory.

SUMMARY OF BACKGROUND DATA

Pain after spinal fusion surgery for AIS may not improve predictably with elapsed healing time, and limited data exist on predictors of the course of pain during the initial months after surgery.

METHODS

Fifty patients ages 11 to 17 (mean = 14.5, standard deviation = 1.9) with AIS and undergoing posterior spinal fusion surgery comprised the study sample. Pain outcomes were assessed at 4 time points after surgery (2-week, 6-week, 3-month, and 6-month postsurgery). Preoperative predictor variables comprising demographics, baseline Cobb angle, body mass index, baseline pain, and psychological variables (anxiety, negative mood, and confidence in ability to control pain) were assessed 2 weeks before surgery. Perioperative predictor variables comprising pain, pain coping efficacy, negative mood, surgery length, length and lowest level of fusion, and analgesic use were assessed by self-report or record review. Multilevel growth models were used to evaluate hypotheses pertaining to predictors of pain trajectories.

RESULTS

Pain level on average declined predictably with days since surgery (b = -0.14 to -0.19, P < 0.01). For 22% of adolescents, pain was at or above baseline levels through 6 months after surgery. Greater baseline pain and anxiety predicted slower improvement in pain, whereas greater confidence in ability to control pain predicted more rapid declines in pain. None of the demographic or medical variables reliably modified postsurgical pain trajectories.

CONCLUSION

Although pain typically declines predictably with healing time from spinal fusion surgery for AIS, higher preoperative levels of pain and anxiety may be risk factors for chronic postsurgical pain whereas greater pain coping efficacy may help optimize postsurgical pain outcomes.

LEVEL OF EVIDENCE

3.

Patients with chronic pain

Preoperative evaluation of patients with chronic pain is important because it may lead to multidisciplinary preoperative treatment of patients' pain and a multimodal analgesia plan for effective pain control. Preoperative multidisciplinary management of chronic pain and comorbid conditions, such as depression, anxiety, deconditioning, and opioid tolerance, can improve patient satisfaction and surgical recovery. Multimodal analgesia using pharmacologic and nonpharmacologic strategies shifts the burden of analgesia away from simply increasing opioid dosing. In more complicated chronic pain patients, multidisciplinary treatment, including pain psychology, physical therapy, judicious medication management, and minimally invasive interventions by pain specialists, can improve patients' satisfaction and surgical outcome.