Background: Optimal needle depth in transforaminal epidural injection (TFEI) is determined by body measurements and is influenced by the needle entry angle. Physician can choose the appropriate needle length and perform the procedure more effectively if depth is predicted in advance. Methods: This retrospective study included patients with lumbosacral pain from a single university hospital. The skin depth from the target point was measured using magnetic resonance imaging transverse images. The depth was measured bilaterally for L4 and L5 TFEIs at 15°, 20°, and 25° oblique angles from the spinous process. Results: A total of 4,632 measurements of 386 patients were included. The lengths of the left and right TFEI at the same level and oblique angle were assessed, and no statistical differences were identified. Therefore, linear regression analysis was performed for bilateral L4 and L5 TFEIs. The R-squared values of height and weight combined were higher than the height, weight, and body mass index (BMI). The following equation was established: Depth (mm) = a – b (height, cm) + c (weight, kg).Based on the equation, maximal BMI capable with a 23G, 3.5-inch, Quincke-type point spinal needle was presented for three different angles (15°, 20°, and 25°) at lumbar levels L4 and L5. Conclusions The maximal BMI that derived from the formulated equation is listed on the table, which can help in preparations for morbid obesity. If a patient has bigger BMI than the one in the table, the clinician should prepare longer needle than the usual spinal needle.

Background: The coronavirus disease 2019 (COVID-19) pandemic has caused significant changes. This study aimed to investigate the impact of COVID-19 on patients with chronic pain. Methods: Patients with chronic pain from 23 university hospitals in South Korea participated in this study. The anonymous survey questionnaire consisted of 25 questions regarding the following: demographic data, diagnosis, hospital visit frequency, exercise duration, time outside, sleep duration, weight change, nervousness and anxiety, depression, interest or pleasure, fatigue, daily life difficulties, and self-harm thoughts. Depression severity was evaluated using the Patient Health Questionnaire-9 (PHQ-9). Logistic regression analysis was used to investigate the relationship between increased pain and patient factors. Results: A total of 914 patients completed the survey, 35.9% of whom had decreased their number of visits to the hospital, mostly due to COVID-19. The pain level of 200 patients has worsened since the COVID-19 outbreak, which was more prominent in complex regional pain syndrome (CRPS). Noticeable post-COVID-19 changes such as exercise duration, time spent outside, sleep patterns, mood, and weight affected patients with chronic pain. Depression severity was more significant in patients with CRPS. The total PHQ-9 average score of patients with CRPS was 15.5, corresponding to major depressive orders. The patients’ decreased exercise duration, decreased sleep duration, and increased depression were significantly associated with increased pain. Conclusions COVID-19 has caused several changes in patients with chronic pain.During the pandemic, decreased exercise and sleep duration and increased depression were associated with patients’ increasing pain.

BACKGROUND: Most depth of anesthesia (DOA) monitors rely on the temporal characteristics of a single-channel electroencephalogram (EEG) and cannot provide spatial or connectivity information. Phase lag entropy (PLE) reflects DOA by calculating diverse connectivity from temporal patterns of phase relationships. The aim of this study was to compare the performance of PLE and bispectral index (BIS) monitors for assessing DOA during anesthesia induction, nerve integrity monitoring (NIM), and anesthesia emergence. METHODS: Thirty-five patients undergoing elective thyroid surgery with recurrent laryngeal nerve NIM received propofol and remifentanil via target-controlled infusion. After applying PLE and BIS monitors, propofol infusion was initiated at a calculated effect site concentration (Ce) of 2 µg/mL and then increased in 1-µg/mL Ce increments. After propofol Ce reached 5 μg/mL, a remifentanil infusion was begun, and anesthesia induction was considered complete. During NIM, PLE and BIS values were compared at a specific time points from platysma muscle exposure to subcutaneous tissue closure. PLE and BIS values were recorded continuously from preanesthetic state to full recovery of orientation; bias and limits of agreement between monitors were calculated. RESULTS: PLE and BIS values decreased progressively with increasing propofol Ce during anesthetic induction and increased by stages during emergence. The prediction probabilities of PLE and BIS for detecting propofol Ce changes were 0.750 and 0.756, respectively, during induction and 0.749 and 0.746, respectively, during emergence. No aberrant PLE or BIS values occurred during NIM. Correlation coefficients for BIS and PLE were 0.98 and 0.92 during induction and emergence, respectively. PLE values were significantly higher than BIS values at full recovery of orientation. Estimated bias between monitors was −4.16 ± 8.7, and 95% limits of agreement were −21.21 to 12.89. CONCLUSION: PLE is a reasonable alternative to BIS for evaluating consciousness and DOA during general anesthesia and during NIM. TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0003490
Anesthesia ; Anesthesia, General ; Bias (Epidemiology) ; Consciousness ; Consciousness Monitors ; Electroencephalography ; Entropy ; Humans ; Information Services ; Propofol ; Recurrent Laryngeal Nerve ; Subcutaneous Tissue ; Superficial Musculoaponeurotic System ; Thyroid Gland