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The 145 recruited patients undergoing elective orthopedic lower-limb surgery had 1 of the following: body mass index greater than 35 kg/m 2 and poorly palpable or impalpable spinous processes, moderate to severe lumbar scoliosis, or previous lumbar spinal surgery. Patients were randomized to receive spinal anesthesia by the conventional surface landmarkYguided technique (group LM) or by ultrasound-guided technique (group US). The study procedures were performed 30 to 45 minutes before surgery. For patients in the LM group, surface landmarks were graded on a 4-point scale as easy, moderate, difficult, or impossible to palpate. After dural puncture was confirmed, spinal anesthesia was provided with 15 mg 0.5% bupivacaine and 100 Kg morphine. Motor and sensory block to the T7 dermatome or higher within 30 minutes of injection indicated successful spinal anesthesia.Patients in the US group had surface anatomic landmarks assessed and graded as was done for the LM group. Ultrasound imaging of the lumbar spine was done using a systematic scanning protocol. A parasagittal oblique view of the lumbosacral spine was obtained, and the L2-3 to L4-5 interlaminar spaces were marked by counting up from the sacrum. A transverse view was then obtained with the same interspinous and interlaminar spaces identified by visualizing the intrathecal space between the ligamentum flavumYdural mater complex and posterior aspect of the vertebral body. The midline location of each interlaminar space was marked on the skin. The intersection of these 2 markings was used to guide a midline approach to spinal anesthesia, which then was provided in the same manner as for the LM group. The primary outcome was the rate of successful dural puncture on the first needle insertion. Secondary outcomes included number of needle insertion attempts for successful puncture, number of needle passes, time required to establish landmarks, time to perform the spinal anesthetic, total procedure time, block-associated pain score, and patient satisfaction with the block procedure.The study was stopped early because an unplanned interim analysis found a substantial difference in all outcomes related to ease of performance of spinal anesthesia. Of the 145 patients, 120 completed the study (60 patients in each group). Successful dural puncture on the first needle insertion attempt was achieved in 65% of group US patients compared with 32% in group LM. The median numbers of needle insertion attempts were 1 in group US and 2 in group LM; the median numbers of needle passes to achieve dural puncture were 6 in group US and 13 in group LM. Time to establish landmarks was 6.7 T 3.1 and 0.6 T 0.5 minutes in the US and LM groups, respectively. This time was partially offset by a reduction in the time needed to perform spinal anesthesia in the 2 groups (5.0 T 4.9 and 7.3 T 7.6 minutes, in the US and LM groups, respectively). The total procedure time was 12.2 T 6.0 minutes in group US and 7.9 T 7.7 minutes in group LM. A subgroup analysis of patients with BMI of greater than 35...

No abstract

None of the preoperative psychosocial measures were associated with the moderate to severe acute pain after VATS. Average expected postoperative pain was the only measure associated with the development of moderate to severe acute pain after VATS.

While cross-subsidization is understood theoretically as involving the sustainability of a cost allocation scheme, it is invoked in regulatory policy contexts, such as the divestiture of AT&T, where costs of serving unregulated markets may be bome by ratepayers of regulated monopolies. We analyze two cross-subsidization tactics--cost misallocation and distorted technological choice--under a spectrum of regulatory cost allocation policies. These tactics lead to higher prices in regulated markets and inefficient production in unregulated markets. Welfare effects are discussed; we conclude with observations on strategic behavior and regulatory policy.