High Prevalence of Neuropathic Pain Component in Patients with Low Back Pain : Evidence from Meta-Analysis

BACKGROUND: Low back pain (LBP) is a complex syndrome which includes a nociceptive (NcP) component, a neuropathic (NeP) component, or a mixture of components (mixed pain). The NeP component (NePC) in LBP is defined as the presence of NeP with or without an NcP. OBJECTIVE: This meta-analysis aimed at assessing the pooled prevalence of NePC in patients with LBP and at identifying the factors causing significant heterogeneity in reported prevalence. STUDY DESIGN: Meta-analysis. METHODS: A systematic literature search was carried out, with inclusion of all epidemiological studies describing the NeP prevalence levels in LBP patients while using standard diagnostic methods. The "pooled prevalence rate (PPR)" of NePC, either on its own or in combination with NcP, was calculated. A pre-specified subgroup analysis was carried out, considering LBP duration, presence of leg pain, diagnostic method(s), and questionnaire(s) used. RESULTS: The meta-analysis included 20 studies relating to a total of 14,269 LBP patients, of whom 7,969 patients (55.8%) were identified as presenting with NePC. The pooled PR (95% CI) of NePC in patients with LBP was 0.47 (0.40 - 0.54), while the pooled PR of NcP was 0.56 (0.48 - 0.63). Higher NePC pooled PR values were identified in LBP with leg pain as compared to uncomplicated LBP (respectively: 0.60; 0.47 - 0.73 vs 0.27; 0.23 - 0.31; Pinteraction < 0.01). LIMITATIONS: The quality of the included studies was assessed using ad-hoc criteria. Due to the limited number of available studies, one may need to be cautious in reaching conclusions about the impact of disease duration on NePC prevalence values. We pooled studies which used a range of different diagnostic methods, with putatively different sensitivity/specificity diagnosing levels. CONCLUSIONS: Overall, high NePC prevalence levels were here identified in LBP patients. As the pain is a subjective phenomenon and there is no gold standard for the diagnosis of NePC, there is the possibility that the pooled effect estimate may alter depending upon the diagnostic method used. KEY WORDS: Neuropathic pain, nociceptive pain, low back pain, symptom-based questionnaire, chronicity.Peer reviewedFinal Published versio

Newer anticoagulants and their impact on interventional pain procedures

Heparins and coumarins have been ruling the anticoagulant class for the past 60 years, but the trend in the drug discovery, prominence of target-based approach, and high-throughput screening has brought newer molecules in the forefront. Newer oral anticoagulants (NOACs) with different therapeutic challenges have largely come up in the past 5 years and overcome the limitations of traditional anticoagulants. The debate for specific guidelines for their use has been on for years. Interventional pain physicians admonished that available guidelines for regional anesthesia in patients receiving anticoagulants were insufficient as pain procedures covered a far broader gamut reflecting diverse goals. Hence, experts from different groups and committees got together and summed up guidelines and stratified interventional pain procedures based separately on patient- and procedure-specific factors. Here, in this review, we discuss the NOACs and their impact on interventional pain procedures

Review Article - Complex regional pain syndrome: A review

Complex regional pain syndrome (CRPS) is a challenging neuropathic pain state, quite difficult to comprehend and treat. Its pathophysiological mechanisms are unclear and its treatment is difficult. Multiple factors play a role in the generation and maintenance of CRPS. A close interdisciplinary collaboration amongst the psychologist, physical and occupational therapists, neurologist and pain medicine consultants is necessary to achieve optimal treatment effects. The primary goals of managing patients with this syndrome are to: 1) perform a comprehensive diagnostic evaluation, 2) be prompt and aggressive in treatment interventions, 3) assess and reassess the patient's clinical and psychological status, 4) be consistently supportive, and 5) strive for the maximal amount of pain relief and functional improvement. This article reviews the different aspects of CRPS including definition, classification, epidemiology and natural history, clinical presentation, pathophysiology and management

Long-term safety and efficacy of intralesional injection of triamcinolone acetonide for sternal keloid pain and pruritis: A double-blind comparison of two concentrations

Background: Intralesional injection of triamcinolone acetonide (TAC) is the most frequently used treatment modality for keloids or hypertrophic scars. However, 20 mg/mL, triamcinolone is reported to have 50% incidence of adverse sequelae. We compared the long-term safety and efficacy of 10 mg/mL with 20 mg/mL intralesional injection of TAC on sternal keloid pain. Methods: Thirty adult patients presenting with pain and/or pruritis at sternal keloid site were randomized into one of the two groups. In group T20 patient received 1 mL of 20 mg/mL TAC, whereas in group T10 patients received 1 mL of 10 mg/mL of TAC intralesional every 2 weeks for a total of 3-4 treatments. Visual analog scale (VAS) scores for pain and pruritis, keloid/scar height, and any adverse sequelae were recorded at 2 weeks interval till 2 months and then at 6, 12, and 15 months. Primary outcome of the study was the percentage of patient developing side effects. Secondary outcome measures were VAS score for pain and itching, keloid height, and recurrence rate of pain or itching. Results: There was a significant decrease in VAS score for pain, pruritis, and keloid height after drug administration in both groups. Side effects was observed in 6 (40%) patients in group T20 and 1 (6.7%) patients in group T10 (P = 0.04). Two patients (13.3%) in group T20 and one in group T10 (6.7%) did not have any improvement in their pain/pruritis scores. Recurrence rate was 13.3% (2 patients) in T20 group compared with 20% (3 patients) in group T10 at 15 months after initial response. Conclusion: Intralesional injection of TAC in concentration of 10 mg/mL is as efficacious as 20 mg/mL for sternal keloid pain but is associated with significantly less side effects

Effective dose 50 of desflurane for laryngeal mask airway removal in anaesthetized children in cataract surgeries with subtenon block

Background: Quantification of the depth of desflurane anesthesia required for laryngeal mask airway (LMA) removal in children has been done with the use of intravenous fentanyl or caudal anesthesia. This study aimed to determine the end-tidal concentration of desflurane required for LMA removal in children without the use of caudal or opioid analgesia in children undergoing elective cataract surgery. Materials and Methods: Our study enrolled 25 American Society of Anesthesiologists I and II children aged 2-10 years, undergoing elective cataract surgery. Anesthesia was induced with sevoflurane and oxygen/nitrous oxide using face mask and a size 2 LMA inserted. A subtenon block was administered in all children before surgical incision. Desflurane was used for maintenance of anesthesia. Predetermined end tidal concentration of desflurane was maintained for 10 min at the end of surgery before LMA removal was attempted. End tidal concentrations were increased/decreased using the Dixon up-down method (with 0.5% as a step size) in the next patient depending on the previous patient′s response. Patient responses to LMA removal were classified as "movement" or "no movement." Results: 50% effective dose (ED 50 ) for successful removal of the LMA with desflurane in the presence of subtenon block was 3.6% (3.20-3.97%) and that the 95% ED 95 was 4.648% (4.15-6.47%). Conclusion: Laryngeal mask airway removal can be successfully accomplished in 50% and 95% anesthetized children at 3.6% and 4.65% end-tidal desflurane concentration

Effect of dexmedetomidine on emergence agitation using desflurane in pediatric cataract surgery

Background: In this study, we compared effectiveness of two doses of dexmedetomidine (0.15 μg/kg and 0.3 μg/kg) in preventing desflurane-induced emergence agitation (EA) in pediatric patients undergoing elective cataract surgery. Methods: It is a prospective double-blinded randomized study conducted on 65 American Society of Anesthesiologists 1 children (2–10 years) who underwent elective cataract surgery at our institute. They were randomized into two equal groups, who received either dexmedetomidine 0.15 μg/kg (Group D0.15) or dexmedetomidine 0.30 μg/kg (Group D0.3) intravenously after induction of anesthesia. An observer blinded to groups recorded heart rate (HR), arterial blood pressure, oxygen saturation, end-tidal carbon dioxide, and respiratory rate (RR) at regular intervals and evaluated preoperative anxiety, state of agitation, and postoperative pain using validated scores. Results: Both groups (Group D0.15, n = 27 vs. Group D0.3, n = 26) were demographically identical. In intraoperative period, the difference in HRs was significantly lower in Group D0.3from 5 min till 15 min of the surgery (P < 0.05), but thereafter, from 20 min till end of surgery, the rates were comparable in both the groups, whereas RR and blood pressure fluctuations were comparable throughout. Postoperative pain scores and postoperative agitation score were significantly lower in Group D0.3than D0.15at all time intervals (P < 0.05). Conclusions: In our study, 0.3 μg/kg intravenous dexmedetomidine was found to be superior to 0.15 μg/kg group in effectively reducing EA and postoperative pain, without producing adverse effects such as hypotension or bradycardia

Metallic Stents for Proximal Tracheal Stenosis: Is It Worth the Risk?

Objective. To demonstrate the risk associated with blocked proximal tracheal stents when a patient presents with acute respiratory distress, with blockage of stent and what is the best management we can offer without damage to the stent and its associated complications. Case Report. A 22-yr-old, male patient, presented in severe respiratory distress. He had history of corrosive poisoning for which he was tracheotomised. A stainless steel wire mesh stent was placed in the trachea, from the subglottis, to just above the carina. One month later, he presented with a critically compromised airway with severe respiratory distress. Emergency tracheostomy was done and the metallic stent had to be cut open, in order to provide an airway. Conclusion. Management of blocked proximal stents with patient in respiratory distress remains a challenge. Formation of granulation tissue is common and fibreoptic bronchoscopic assisted intubation may not always be possible. A regular follow up of all patients with stents is essential. Placement of stents within a few centimetres of cricotracheal junction should not be encouraged for long term indications

Best neonatal outcome following emergency cesarean delivery in nonreassuring fetal heart rate: General or a low-dose spinal anesthesia

Aims: Spinal hypotension using conventional local anesthetic doses for elective cesarean delivery (CD) has been associated with fetal acidosis. The optimum anesthetic technique for laboring women with nonreassuring fetal heart trace (FHR) and its effects on neonatal outcome has not been well studied. Materials and Methods: Thirty laboring parturients with a nonreassuring FHR undergoing emergency CD (category 2) were included in this study. The parturients were randomized to receive a low-dose spinal anesthesia (LDSA group) 8 mg hyperbaric 0.5% bupivacaine with 20 μg fentanyl, or standard general anesthesia (GA group). Systolic blood pressure was maintained at >100 mmHg till delivery of the fetus using phenylepherine boluses. The primary outcome variable was cord blood gas base excess >8 meq/L. Statistical Analysis: Assuming an SD of 7.5 and difference of 5 as clinically significant difference in base deficit, we required 15 patients in each group with α of 0.05 and power of 90%. Student′s t test, two-way repeated measures analysis of variance (ANOVA) and Chi square test were used to analyze the data. Results: The incidence of fetal acidosis was higher in the GA group. Lower APGAR scores at 1 and 5 min and a greater need for immediate resuscitation was observed in fetuses exposed to GA. All patients in the LDSA group achieved adequate surgical block as well as stable hemodynamics. No adverse event was observed with either of the techniques. Conclusion: A LDSA is associated with better neonatal outcome in women with nonreassuring FHR as compared with GA