Neuropathic pain component and its association with time elapsed since pain onset in patients with low back pain.

BACKGROUND: Time elapsed since pain onset might affect the likelihood of neuropathic component in low back pain. The aim of this study was to investigate the relationship between neuropathic pain component and pain duration in patients with low back pain and to identify factors associated with neuropathic pain component. METHODS: Patients with low back pain who received treatment at our clinic were enrolled. Neuropathic component was assessed using the painDETECT questionnaire at the initial visit. PainDETECT scores and the results for each item were compared according to pain duration category (< 3 months, 3 months to 1 year, 1 year to 3 years, 3 years to 10 years, and ≥ 10 years). A multivariate analysis was used to identify factors associated with neuropathic pain component (painDETECT score ≥ 13) in low back pain. RESULTS: A total of 1957 patients, including 255 patients who reported neuropathic-like pain symptoms (13.0%), fully satisfied the study criteria for analysis. No significant correlation between painDETECT score and pain duration was observed (ρ = -0.025, p = 0.272), and there were no significant differences between median painDETECT score or trend of change in the proportion of patients with neuropathic component and the pain duration category (p = 0.307, p = 0.427, respectively). The electric shock-like pain symptom was frequently reported in patients with acute low back pain, and the persistent pain pattern with slight fluctuations was predominant in chronic low back pain. The pattern of attacks with pain between them was much less common in patients with pain for 10 years or longer. Multivariate analysis revealed that a history of lumbar surgery, severe maximum pain, opioid use, lumbosacral radiculopathy, and sleep disturbance were significantly associated with a neuropathic component in low back pain. CONCLUSION: Time elapsed since current pain onset did not correlate with neuropathic pain component in patients with low back pain. Therefore, diagnostic and therapeutic approaches for this condition should be based on a multidimensional evaluation at assessment and not on pain duration alone.

Evaluation of Sagittal Spinopelvic Alignment on Analgesic Efficacy of Lumbar Epidural Steroid Injection in Geriatric Patients.

Background and Objectives: The aim of this study was to evaluate the impact of sagittal imbalance based on pelvic incidence−lumbar lordosis (PI-LL) mismatch on the analgesic efficacy of epidural steroid injection in geriatric patients. Materials and Methods: Patients aged 65 years or older who received lumbar epidural steroid injections under fluoroscopy were enrolled. The cutoff of PI-LL mismatch >20° was used as an indicator of a marked sagittal imbalance. The cross-sectional area of the psoas and paraspinal muscles, as well as the paraspinal fat infiltration grade were measured. A 50% or more decrease in pain score at four weeks after injection was considered as good analgesia. Variables were compared between PI-LL ≤ 20° and >20° groups and multivariate analysis was used to identify factors related to pain relief after injection. Results: A total of 237 patients consisting of 150 and 87 patients in the PI-LL ≤ 20° and >20° groups, respectively, were finally analyzed. Female patients, patients with lumbar surgery history, and the smaller cross-sectional area of the psoas muscles were predominantly observed in patients with sagittal imbalance. There was no difference in analgesic outcome after injection according to the PI-LL mismatch (good analgesia 60.0 vs. 60.9%, p = 0.889). Multivariate analysis showed that pre-injection opioid use, moderate to severe foraminal stenosis, and high-graded paraspinal fat infiltration were significantly associated with poor analgesia after injection. Conclusions: There was no significant correlation between sagittal spinopelvic alignment and pain relief after lumbar epidural steroid injection for geriatric patients.

Effects of dexmedetomidine on oxygenation and lung mechanics in patients with moderate chronic obstructive pulmonary disease undergoing lung cancer surgery: A randomised double-blinded trial.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a risk factor that increases the incidence of postoperative cardiopulmonary morbidity and mortality after lung resection. Dexmedetomidine, a selective α2-adrenoreceptor agonist, has been reported previously to attenuate intrapulmonary shunt during one-lung ventilation (OLV) and to alleviate bronchoconstriction. OBJECTIVE: The objective is to determine whether dexmedetomidine improves oxygenation and lung mechanics in patients with moderate COPD during lung cancer surgery. DESIGN: A randomised, double-blinded, placebo-controlled study. SETTING: Single university hospital. PARTICIPANTS: Fifty patients scheduled for video-assisted thoracoscopic surgery who had moderate COPD. Patients were randomly allocated to a control group or a Dex group (n = 25 each). INTERVENTIONS: In the Dex group, dexmedetomidine was given as an initial loading dose of 1.0  µg  kg(-1) over 10  min followed by a maintenance dose of 0.5  µg  kg(-1)  h(-1) during OLV while the control group was administered a comparable volume of 0.9% saline. Data were measured at 30  min (DEX-30) and 60  min (DEX-60) after dexmedetomidine or saline administration during OLV. MAIN OUTCOME MEASURES: The primary outcome was the effect of dexmedetomidine on oxygenation. The secondary outcome was the effect of dexmedetomidine administration on postoperative pulmonary complications. RESULTS: Patients in the Dex group had a significantly higher PaO2/FIO2 ratio (27.9 ±â€Š5.8 vs. 22.5 ±â€Š8.4 and 28.6 ±â€Š5.9 vs. 21.0 ±â€Š9.9 kPa, P < 0.05), significantly lower dead space ventilation (19.2 ±â€Š8.5 vs. 24.1 ±â€Š8.1 and 19.6 ±â€Š6.7 vs. 25.3 ±â€Š7.8%, P < 0.05) and higher dynamic compliance at DEX-30 and DEX-60 (P = 0.0001 and P = 0.0184) compared with the control group. In the Dex group, the PaO2/FIO2 ratio in the postoperative period was significantly higher (P = 0.022) and the incidence of ICU admission was lower than in the control group. CONCLUSION: Dexmedetomidine administration may provide clinically relevant benefits by improving oxygenation and lung mechanics in patients with moderate COPD undergoing lung cancer surgery. TRIAL REGISTRATION: ClinicalTrial.gov identifier: NCT 02185430.

Accuracy of pilot balloon palpation for cuff pressure assessment in small versus large sized tubes: a prospective non-randomized observational study.

Pilot balloon palpation is still a commonly used method to evaluate cuff pressure of the endotracheal tube after intubation. This study determined whether the size of the tracheal tube influenced the accuracy of pilot balloon palpation. A prospective observational analysis of 208 patients intubated with an endotracheal tube of internal diameter (ID) 6.0 or 8.0 was conducted. An anesthesiologist judged the cuff pressure by manual pilot balloon palpation, and then measured the cuff pressure with a pressure gauge. Cuff pressure exceeding 20-30 cmH2O was defined as false recognition. The intracuff pressure was significantly higher in ID 6.0 tube than in the ID 8.0 tube (41.9 ± 18.8 cmH2O vs. 30.3 ± 11.9 cmH2O, p < 0.001). The number of patients that were mistakenly perceived to have appropriate cuff pressure by pilot balloon palpation was significantly higher in the ID 6.0 group compared to the ID 8.0 group (85 (81.7%) vs. 64 (61.5%), p = 0.001). Therefore, a smaller tube size may further increase risk of inaccurate measurement by pilot balloon palpation and although pressure gauge is recommended for all sizes to maximize accuracy, groups with increased risk factors should be targeted for standardized use of the pressure gauge.

Neuropathic-like Pain Symptoms and Their Association with Muscle Strength in Patients with Chronic Musculoskeletal Pain.

The relationship between sarcopenia and pain remains unclear; thus, this study evaluated whether muscle strength is independently associated with neuropathic-like pain symptoms in patients with chronic musculoskeletal pain. A cut-off score of painDETECT ≥13 was used to indicate a possible neuropathic component. Handgrip strength was measured, and muscle mass was estimated. A total of 2599 patients, including 439 patients who reported neuropathic-like pain symptoms (16.9%), were included for analysis. Handgrip strength was significantly lower in patients experiencing neuropathic-like pain symptoms (23.23 ± 10.57 vs. 24.82 ± 10.43 kg, p < 0.001), and this result was chiefly found in female patients. However, there was no difference in estimated muscle mass. Shorter duration of pain, opioid usage, pain in lower limbs, sleep disturbance, and lower handgrip strength were significantly associated with neuropathic-like pain symptoms. In patients with handgrip strength below the reference values by sex, experiencing radiating pain and at least moderate sensory symptoms by light touch and thermal stimulation were more frequently reported. In conclusion, lower handgrip strength appeared to be an independent factor associated with symptoms suggestive of neuropathic pain in this population. Interventional studies are required to determine whether improvement in muscle strength can reduce the neuropathic pain component in chronic musculoskeletal pain.

The Effects of Dexmedetomidine on Myocardial Function Assessed by Tissue Doppler Echocardiography During General Anesthesia in Patients With Diastolic Dysfunction: A CONSORT-Prospective, Randomized, Controlled Trial.

Dexmedetomidine is a commonly used sedative and adjuvant agent to general anesthesia. The present was designed to evaluate the effects of dexmedetomidine on myocardial function by using tissue Doppler echocardiography during general anesthesia in patients with diastolic dysfunction.Forty patients undergoing orthostatic surgery with ejection fraction preserved diastolic dysfunction grade 2 or 3 were randomly allocated to the Control and Dex group (n = 20, each). In the Dex group, dexmedetomidine was given as an initial loading dose of 1.0 µg/kg over 10 minutes followed by a maintenance dose of 0.5 µg/kg/h. The ratio of peak early diastolic transmitral or transtricuspid inflow velocity to early diastolic mitral or tricuspid annular velocity (LV or RV E/e') and left or right ventricular myocardial performance index (LV or RV MPI) were measured at before and after the administration dexmedetomidine or saline.The Dex group showed significant decrease of heart rate (P = 0.038), and increase of mean blood pressure (P < 0.001), LV E/e' (P = 0.025), and LV MPI (P < 0.001) compared to those of the Control group on a linear mixed model analysis. Also, the Dex group showed significant increase of RV E/e' (P < 0.001) and RV MPI (P = 0.028) compared to those of the Control group.Intraoperative dexmedetomidine administration during general anesthesia was appeared to deteriorate biventricular function in patients with diastolic dysfunction. We suggest careful consideration and a need for reducing dosage when administrating dexmedetomidine in patients with diastolic dysfunction.