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Polycyclic aromatic hydrocarbons (PAHs) are major air pollutants that are ubiquitously produced by the combustion of organic materials, and it is extremely important to identify their pollution sources. In this study, molecular fingerprinting and compound class-specific radiocarbon dating (CCSRA) were performed on PAHs from canal sediments and air samples collected in Kolkata, India's third largest city (population approximately 16 million), where PAHs pollution has been a serious problem. Average PAH (Σ12-parent PAHs) concentrations in air samples were 65.1 ng m–3 in summer and 70.9 ng m–3 in winter and in canal sediments were 32.7 µg g–1, which are classified as "very high-level" pollution. Molecular fingerprinting using methyl-PAH/PAH (MPAHs/PAHs) ratios and isomer pair ratios with molecular weights of 178, 202, 228, and 276 suggested that wood and coal combustion were the dominant sources of PAHs in the sediment, and that atmospheric PAHs were influenced by oil combustion in addition to them. The fraction of contemporary carbon (ƒC) of sedimentary PAHs (0.056–0.100), together with the extremely low MPAHs/PAHs ratio results, lead to the conclusion that the major source of the high concentration of PAHs in the canals is from coal combustion. On the other hand, the ƒC of atmospheric PAHs (0.272–0.369) was close to the share of biomass fuels in India's domestic fuel consumption in 2011 (about 35%). Furthermore, the observed ƒC-discrepancy between atmospheric and sedimentary PAHs in the same urban environment was interpreted to give an insight into the loading pathway of PAHs to canal sediments in Kolkata. [ABSTRACT FROM AUTHOR]

Author(s): Tasuku Fujii [sup.1], Yasuyuki Shibata [sup.2], Yasutaka Ban [sup.3], Akira Shitaokoshi [sup.3], Kunihiko Takahashi [sup.4], Shigeyuki Matsui [sup.4], Kimitoshi Nishiwaki [sup.1] Author Affiliations: (1) grid.27476.30, 0000 0001 0943 978X, [...], Purpose Thoracic paravertebral block (TPVB) provides a unilateral nerve block at multiple intercostal levels allowing injection of a local anesthetic into paravertebral space (PVS) via a needle or catheter. However, the most effective injection method remains unclear. This study compared the real-time spread of ropivacaine between two paravertebral injection methods using thoracoscopy. Methods Thirty-four patients scheduled for thoracoscopic surgery were randomly allocated into the Needle or Catheter groups, and performed transverse in-plane ultrasound-guided TPVB. The Needle group received 20 ml of 0.5% ropivacaine via a needle placed into the lateral edge of PVS; the Catheter group received the same dose of ropivacaine via a catheter inserted 5 cm into PVS. The primary outcome was the spreading pattern of ropivacaine in each group. The secondary outcome was intraoperative vasopressor requirement after paravertebral injection. Results In the Needle group, all cases showed ropivacaine spread to multiple intercostal levels, mainly across the ribs. Contrastingly, the Catheter group showed variable spreading patterns; multiple intercostal levels (n = 10) [across the ribs (n = 4), anterolateral aspect of the vertebral bodies (n = 6)] or unobservable spreading (no change; n = 7) (P = 0.007). Vasopressors were required in two and ten cases in the Needle and Catheter groups, respectively (P = 0.010). Conclusion Paravertebral injection via a needle typically resulted in spreading to multiple intercostal levels, especially across the ribs on the peripheral side of injection site, whereas injection via a catheter resulted in variable spreading patterns. Therefore, injections via needles are more stable.

Author(s): Takahiro Tamura [sup.1] , Shuichi Yokota [sup.2] , Shigeki Ito [sup.3] , Yasuyuki Shibata [sup.1] , Kimitoshi Nishiwaki [sup.1] Author Affiliations: (Aff1) 0000 0001 0943 978X, grid.27476.30, Department of [...], Purpose Previous work showed that 20 mL of local anesthetic (LA) did not spread into the paravertebral space (PVS) via the intramuscular quadratus lumborum block (QLBi). If spread of LA into the PVS can be achieved by increasing the total LA volume, QLBi can be more effective. We hypothesized that a larger volume of LA for the QLBi would spread into the PVS. Methods This crossover volunteer study included five healthy men. For comparison, both the ultrasound-guided QLB type 2 (QLB2) and QLBi were employed on opposite sides of each volunteer, and the spread of LA solution (0.7 mL/kg) mixed with contrast media in the PVS was assessed 1 h after the first injection using magnetic resonance imaging. Sensory loss was evaluated by pinprick 90 min post-injection. Each volunteer underwent both QLB types, and the same procedures were administered on opposite sides 7 days after the first experiment. Results In total, 20 QLB blocks (10 QLB2 and 10 QLBi) were performed. LA did not spread into the PVS after the QLBi. The sensory block area included the lower abdomen after the QLB2, but not after the QLBi. The sensory block area did not extend to the upper abdominal region or the midline of the lower abdomen with either block method. Conclusion LA administered by the QLB2 spreads into the PVS of T10-T12, resulting in lower and lateral abdominal sensory loss. In contrast, LA administered by the QLBi does not spread into the PVS and results in only lateral abdominal sensory loss.

Author(s): Takahiro Tamura [sup.1] [sup.2] , Shoichi Mori [sup.3] , Atsushi Mori [sup.4] , Masahiko Ando [sup.5] , Shuichi Yokota [sup.1] , Yasuyuki Shibata [sup.2] , Kimitoshi Nishiwaki [sup.2] Author [...], Purpose We conducted a comparative study to evaluate analgesic efficacy between paravertebral block via the surgical field (PVB-sf), in which the catheter was inserted into the ventral side of the sympathetic trunk in the paravertebral space by a thoracic surgeon under thoracoscopic visualization, and epidural block (Epi) using ropivacaine for post-thoracotomy pain relief. Methods Lung cancer patients scheduled for lobectomy via thoracotomy were randomly allocated to receive either PVB-sf or Epi (n = 36 per group). Before thoracotomy closure, 0.375% ropivacaine was administered as a bolus (PVB-sf, 20 mL; Epi, 5 mL), followed by a 300-mL continuous infusion of 0.2% ropivacaine at 5 mL/h. Postoperative pain was assessed using a visual analog scale (VAS) score at various time points, including the primary endpoint of 2 h after ropivacaine bolus injection. Sensory block area, vital signs, serum ropivacaine concentrations, and side effects were also evaluated. Results The Epi group showed significantly lower VAS scores and blood pressure and a wider sensory block area than the PVB-sf group at all evaluation time points. While the mean serum ropivacaine concentration in the PVB-sf group was significantly higher than that in the Epi group until 1 h after injection of the ropivacaine bolus, there was no significant difference at any subsequent assessment point. The incidence of side effects was similar between the groups. Conclusion The Epi was superior to PVB-sf for the management of post-thoracotomy pain in this patient cohort. The number of dermatomes anaesthetized by Epi was greater than that anaesthetized by PVB-sf. No difference in complication rates was observed between the two groups.