Harsha Shanthanna

Benefits and safety of gabapentinoids in chronic low back pain: A systematic review and meta-analysis of randomized controlled trials.

Background and objective Chronic Low Back Pain (CLBP) is very common, with a lifetime prevalence between 51% and 80%. In majority, it is nonspecific in nature and multifactorial in etiology. Pregabalin (PG) and Gabapentin (GB) are gabapentinoids that have demonstrated benefit in neuropathic pain conditions. Despite no clear rationale, they are increasingly used for nonspecific CLBP. They necessitate prolonged use and are associated with adverse effects and increased cost. Recent guidelines from the National Health Service (NHS), England, expressed concerns on their off-label use, in addition to the risk of misuse. We aimed to assess the effectiveness and safety of gabapentinoids in adult CLBP patients. Methods Electronic databases of MEDLINE, EMBASE, and Cochrane were searched from their inception until December 20th, 2016. We included randomized control trials reporting the use of gabapentinoids for the treatment of CLBP of >3 months duration, in adult patients. Study selection and data extraction was performed independently by paired reviewers. Outcomes were guided by Initiative on Methods, Measurement and Pain Assessment in Clinical Trials guidelines, with pain relief and safety as the primary outcomes. Meta-analyses were performed for outcomes reported in 3 or more studies. Outcomes were reported as mean differences (MDs) or risk ratios (RRs) with their corresponding 95% confidence intervals (CIs), and I2 in percentage representing the percentage variability in effect estimates that could be explained by heterogeneity. GRADE (Grading of Recommendations Assessment, Development, and Evaluation) was used to assess the quality of evidence. Results Out of 1,385 citations, eight studies were included. Based on the interventions and comparators, studies were analyzed in 3 different groups. GB compared with placebo (3 studies, n = 185) showed minimal improvement of pain (MD = 0.22 units, 95% CI [−0.5 to 0.07] I2 = 0%; GRADE: very low). Three studies compared PG with other types of analgesic medication (n = 332) and showed greater improvement in the other analgesic group (MD = 0.42 units, 95% CI [0.20 to 0.64] I2 = 0; GRADE: very low). Studies using PG as an adjuvant (n = 423) were not pooled due to heterogeneity, but the largest of them showed no benefit of adding PG to tapentadol. There were no deaths or hospitalizations reported. Compared with placebo, the following adverse events were more commonly reported with GB: dizziness-(RR = 1.99, 95% CI [1.17 to 3.37], I2 = 49); fatigue (RR = 1.85, 95% CI [1.12 to 3.05], I2 = 0); difficulties with mentation (RR = 3.34, 95% CI [1.54 to 7.25], I2 = 0); and visual disturbances (RR = 5.72, 95% CI [1.94 to 16.91], I2 = 0). The number needed to harm with 95% CI for dizziness, fatigue, difficulties with mentation, and visual disturbances were 7 (4 to 30), 8 (4 to 44), 6 (4 to 15), and 6 (4 to 13) respectively. The GRADE evidence quality was noted to be very low for dizziness and fatigue, low for difficulties with mentation, and moderate for visual disturbances. Functional and emotional improvements were reported by few studies and showed no significant improvements. Conclusions and relevance Existing evidence on the use of gabapentinoids in CLBP is limited and demonstrates significant risk of adverse effects without any demonstrated benefit. Given the lack of efficacy, risks, and costs associated, the use of gabapentinoids for CLBP merits caution. There is need for large high-quality trials to more definitively inform this issue. Trial registration PROSPERO CRD42016034040

Early and effective use of ketamine for treatment of phantom limb pain

Treatment for phantom limb pain is difficult and challenging. There is often suboptimum treatment with fewer than 10% receiving lasting relief. Treatments based broadly on other neuropathic pains may not be appropriate for a clinical success. We report a case of phantom limb pain, which proved resistant to multiple analgesics, including opioids and continuous epidural blockade. Treatment with intravenous (IV) ketamine as an alternate day infusion, gave complete remission of phantom limb pain. This demonstrates an early and effective use of a potent NMDA antagonist for treatment of phantom limb pain. Mechanisms underlying phantom limb pain are briefly discussed.

Comparative study of ultrasound-guided continuous femoral nerve blockade with continuous epidural analgesia for pain relief following total knee replacement

Background: Regional analgesia is widely used for total knee replacement surgeries (TKR) as it has lesser side-effects and better analgesic efficacy when compared with traditional oral analgesics. Peripheral nerve blockade has also been utilized, including continuous infusion techniques. With the use of ultrasound, the needle and catheter placement can be done accurately under real-time guidance. This may prove a more suitable approach compared with the epidural technique. Aims: Post-operative analgesia in TKR patients was compared between continuous epidural analgesia (CEA) and continuous femoral block (CFB) techniques. VAS scores and use of rescue analgesic were used as parameters. Secondary aims included comparison of rehabilitation scores and side-effects in the form hypotension, vomiting, itching and urinary retention. Settings and Design: Randomised, controlled, non-blinded study done in a tertiary care private hospital. Methods: Forty-two patients fulfilling the study criteria were randomised into the CEA and CFB groups. In total, four patients: three in the CFB group and one in the CEA group, were excluded because of catheter migration. Statistical Analysis: Mean VAS score at 6, 6–24, 24–48 and 48–72 h were considered. Significance was assessed at the 5% level. Results and Conclusion: VAS scores were significantly high (P=0.001) in the femoral group at 6 h, after which there was a declining trend, and scores were essentially similar from 24 h. Common side-effects were more common in the CEA group. Our study shows that CFB gives equivalent analgesia compared with CEA in TKR patients with clinically meaningful decrease in side-effects.

Ultrasound guided selective cervical nerve root block and superficial cervical plexus block for surgeries on the clavicle.

We report the anaesthetic management of two cases involving surgeries on the clavicle, performed under superficial cervical plexus block and selective C5 nerve root block under ultrasound (US) guidance, along with general anaesthesia. Regional analgesia for clavicular surgeries is challenging. Our patients also had significant comorbidities necessitating individualised approach. The first patient had a history of emphysema, obesity, and was allergic to morphine and hydromorphone. The second patient had clavicular arthritis and pain due to previous surgeries. He had a history of smoking, Stevens-Johnson syndrome, along with daily marijuana and prescription opioid use. Both patients had an effective regional block and required minimal supplementation of analgesia, both being discharged on the same day. Interscalene block with its associated risks and complications may not be suitable for every patient. This report highlights the importance of selective regional blockade and also the use of US guidance for an effective and safe block.

Hyperbaric Versus Isobaric Bupivacaine for Spinal Anesthesia: Systematic Review and Meta-analysis for Adult Patients Undergoing Noncesarean Delivery Surgery

BACKGROUND: It is widely believed that the choice between isobaric bupivacaine and hyperbaric bupivacaine formulations alters the block characteristics for the conduct of surgery under spinal anesthesia. The aim of this study was to systematically review the comparative evidence regarding the effectiveness and safety of the 2 formulations when used for spinal anesthesia for adult noncesarean delivery surgery. METHODS: Key electronic databases were searched for randomized controlled trials, excluding cesarean delivery surgeries under spinal anesthesia, without any language or date restrictions. The primary outcome measure for this review was the failure of spinal anesthesia. Two independent reviewers selected the studies and extracted the data. Results were expressed as relative risk (RR) or mean differences (MDs) with 95% confidence intervals (CIs). RESULTS: Seven hundred fifty-one studies were identified between 1946 and 2016. After screening, there were 16 randomized controlled clinical trials, including 724 participants, that provided data for the meta-analysis. The methodological reporting of most studies was poor, and appropriate judgment of their individual risk of bias elements was not possible. There was no difference between the 2 drugs regarding the need for conversion to general anesthesia (RR, 0.60; 95% CI, 0.08–4.41; P = .62; I2 = 0%), incidence of hypotension (RR, 1.15; 95% CI, 0.69–1.92; P = .58; I2 = 0%), nausea/vomiting (RR, 0.29; 95% CI, 0.06–1.32; P = .11; I2 = 7%), or onset of sensory block (MD = 1.7 minutes; 95% CI, −3.5 to 0.1; P = .07; I2 = 0%). The onset of motor block (MD = 4.6 minutes; 95% CI, 7.5–1.7; P = .002; I2 = 78%) was significantly faster with hyperbaric bupivacaine. Conversely, the duration of motor (MD = 45.2 minutes; 95% CI, 66.3–24.2; P < .001; I2 = 87%) and sensory (MD = 29.4 minutes; 95% CI, 15.5–43.3; P < .001; I2 = 73%) block was longer with isobaric bupivacaine. CONCLUSIONS: Both hyperbaric bupivacaine and isobaric bupivacaine provided effective anesthesia with no difference in the failure rate or adverse effects. The hyperbaric formulation allows for a relatively rapid motor block onset, with shorter duration of motor and sensory block. The isobaric formulation has a slower onset and provides a longer duration of both sensory and motor block. Nevertheless, the small sample size and high heterogeneity involving these outcomes suggest that all the results should be treated with caution.

A brief overview of systematic reviews and meta-analyses

Systematic reviews (SRs) are performed to acquire all evidence to address a specific clinical question and involve a reproducible and thorough search of the literature and critical appraisal of eligible studies. When combined with a meta-analysis (quantitatively pooling of results of individual studies), a rigorously conducted SR provides the best available evidence for informing clinical practice. In this article, we provide a brief overview of SRs and meta-analyses for anaesthesiologists.

Gabapentinoids for chronic low back pain: a protocol for systematic review and meta-analysis of randomised controlled trials

Introduction Chronic low back pain (CLBP) is a common condition and causes significant pain, distress and disability across the world. It is multifactorial in aetiology and is challenging to manage. Although the underlying mechanism of pain is predominantly non-specific, many argue that there is a substantial neuropathic pain element. Neuropathic pain is more severe, with significant disability. Gabapentinoids, including gabapentin and pregabalin, have proven efficacy in some neuropathic pain conditions. Despite no clear evidence, a substantial population of patients with CLBP are treated with gabapentinoids. Objectives We aim to assess whether the use of gabapentinoids is effective and safe in the treatment of predominant CLBP, by conducting a systematic review and meta-analysis of randomised control trials (RCTs). Methodology We will search the databases of MEDLINE, EMBASE and Cochrane for RCTs published in English language and have used gabapentinoids for the treatment of CLBP. Study selection and data extraction will be performed independently by paired reviewers using structured electronic forms, piloted between pairs of reviewers. The review outcomes will be guided by Initiative on Methods, Measurement and Pain Assessment in Clinical Trials guidelines, with pain relief as the primary outcome. We propose to carry out meta-analysis if there are three or more studies in a particular outcome domain, using a random effects model. Pooled outcomes will be reported as weighted mean differences or standardised mean differences and risk ratios with their corresponding 95% CIs, for continuous outcomes and dichotomous outcomes, respectively. Rating of quality of evidence will be reported using GRADE summary of findings table. Discussion The proposed systematic review will be able to provide valuable evidence to help decision-making in the use of gabapentinoids for the treatment of CLBP. This will help advance patient care and potentially highlight limitations in existing evidence to direct future research. Ethics and dissemination Being a systematic review, this study would not necessitate ethical review and approval. We plan to report and publish our study findings in a high impact medical journal, with online access. Trial registration number CRD42016034040.

Intrathecal hyperbaric versus isobaric bupivacaine for adult non-caesarean-section surgery: systematic review protocol

Introduction Bupivacaine is the most commonly used local anaesthetic for spinal anaesthesia (SA). There are two forms of commercially available bupivacaine; isobaric bupivacaine (IB): a formulation with a specific gravity or density equal to cerebrospinal fluid, and hyperbaric bupivacaine (HB): a formulation with density heavier than cerebrospinal fluid. The difference in densities of the two available preparations is believed to affect the diffusion pattern that determines the effectiveness, spread and side-effect profile of bupivacaine. This systematic review will summarise the best available evidence regarding the effectiveness and safety on the use of HB compared with IB, when used to provide SA for surgery. Primarily, we will analyse the need for conversion to general anaesthesia. As secondary outcomes, we will compare the incidence of hypotension, incidence of nausea/vomiting, the onset time and duration of anaesthesia. Methods and analysis We will search key electronic databases using search strategy (1) injections, spinal OR intrathecal OR subarachnoid; (2) bupivacaine OR levobupivacaine; (3) hypobaric OR isobaric OR plain; (4) baricity. We will search MEDLINE, EMBASE and Cochrane databases, from their inception for randomised controlled trials, with no restrictions on language. Caesarean section surgery will be excluded. 2 reviewers will independently extract the data using a standardised form. Extracted items will include study characteristics, risk of bias domains, as per modified Cochrane risk of bias, participant disposition and study outcomes. We will conduct a meta-analysis for variables that can be compared across the studies. We will evaluate clinical heterogeneity by qualitatively appraising differences in study characteristics in participants, interventions and the outcomes assessed. We will report our findings as relative risks (dichotomous), and weighted mean differences (continuous) for individual outcomes, along with their 95% CIs. Ethics and dissemination We plan to submit, and will publish, our findings in a peer-reviewed scientific journal, and present our results at national and international meetings. Trial registration number CRD42015017672.

Abnormal vaginal bleeding after epidural steroid injection: is there a cause for concern?

Commentary on: Suh-Burgmann E, Hung YY, Mura J. Abnormal vaginal bleeding after epidural steroid injection: a paired observation cohort study. Am J Obstet Gynecol 2013;209:206.e1–6.[OpenUrl][1][CrossRef][2][PubMed][3][Web of Science][4] Epidural steroid injections (ESI) are the most commonly performed intervention for chronic axial pain. In the USA alone, the number of ESIs administered to Medicare recipients almost doubled between 2000 and 2004 (from 740 845 to 1 437 962 procedures/year).1 A recent systematic review found high-quality evidence that ESI for sciatica results in small, short-term (>2 weeks but ≤3 months) improvements in pain and disability; however, neither effects remained significant at ≥12 months of follow-up.1 ESI are associated with adverse effects that may be related to the technical approach or due to the effect of the steroids themselves,2 but there is very limited … [1]: {openurl}?query=rft.jtitle%253DAm%2BJ%2BObstet%2BGynecol%26rft.volume%253D157%26rft.spage%253D865%26rft_id%253Dinfo%253Adoi%252F10.7326%252F0003-4819-157-12-201212180-00564%26rft_id%253Dinfo%253Apmid%252F23362516%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [2]: /lookup/external-ref?access_num=10.7326/0003-4819-157-12-201212180-00564&link_type=DOI [3]: /lookup/external-ref?access_num=23362516&link_type=MED&atom=%2Febmed%2F19%2F2%2Fe16.atom [4]: /lookup/external-ref?access_num=000312583200016&link_type=ISI

Airway management in the presence of cervical spine instability: A cross-sectional survey of the members of the Indian Society of Neuroanaesthesiology and Critical Care

Background and Aims: There is a paucity of clinical practice guidelines for the ideal approach to airway management in patients with cervical spine instability (CSI). The aim of this survey was to evaluate preferences, perceptions and practices regarding airway management in patients with CSI among neuroanaesthesiologists practicing in India. Methods: A 25-item questionnaire was circulated for cross-sectional survey to 378 members of the Indian Society of Neuroanaesthesiology and Critical Care (ISNACC) by E-mail. We sent four reminders and again submitted our survey to non-responders during the 2017 annual ISNACC meeting. Apart from demographic information, the survey captured preferred methods of intubation and airway management for patients with CSI and their justification. Regression analysis was used to identify factors associated with the use of indirect technique for intubation. Results: Only 122 out of the 378 anaesthesiologists responded to our survey. Most respondents were senior consultants, working in training hospitals, and performed ≥25 intubations per year for CSI patients. The majority of neuroanaesthesiologists (78.7%; n = 96) preferred indirect techniques for elective intubation. However, 45 anaesthesiologists (36.9%) preferred indirect techniques for emergency intubation. In an adjusted analysis, preference for patients to be conscious during intubation was significantly associated with the use of indirect techniques (odds ratio = 3.79; confidence interval = 1.52–9.49, P < 0.01). Conclusions: Among ISNACC members, indirect techniques are preferred for elective intubation of patients with CSI, while direct laryngoscopy is preferred for emergency intubation.