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Purpose The purpose was to compare open and arthroscopic acromioclavicular joint (ACJ) resection. Methods We retrospectively reviewed 103 patients (105 shoulders) who underwent ACJ resection between 2000 and 2005. There were 56 women and 47 men with a mean age of 48 years. The mean duration of follow‐up was 51 months (range, 15 to 91 months). Arthroscopic ACJ resection by use of a direct approach was performed in 81 shoulders (group A), and open ACJ resection was performed in 24 shoulders (group B). Results were graded according to pain relief both subjectively and objectively with cross‐body adduction testing and direct palpation of the ACJ, subjective shoulder value, Constant score, and improved function. Results The Constant scores increased from 50 (range, 34 to 65) to 89 (range, 39 to 100) in group A ( P < .0001) and from 46 (range, 22 to 63) to 87 (range, 43 to 100) in group B ( P < .0001). There was no statistical difference in the postoperative normalized Constant score between group A and group B ( P = .47). Pain with cross‐body adduction testing and palpation of the ACJ improved in 76 shoulders (94%) in group A and 22 shoulders (92%) in group B. No patients had signs or symptoms of ACJ anteroposterior instability. Revision ACJ resection was performed in 5 patients (5 shoulders [6.2%]) in group A and 1 shoulder (4.2%) in group B ( P = .37). The radiographs of the patients who underwent revision showed that 3 patients (3.7%) from group A had regrowth of the distal clavicle; in addition, 2 patients (2.5%) from group A and 1 patient (4.3%) from group B had incomplete distal clavicle excision. Conclusions This study did not show a significant difference in the outcome between arthroscopic and open ACJ resection. Incomplete excision and regrowth of the distal clavicle are the most common causes of revision. Although only the arthroscopic group showed a small percentage of patients (3.7%) with regrowth of the distal clavicle, the number is too small to assume that this complication is the result of the arthroscopic technique only. Level of Evidence Level IV, therapeutic case series.

Oxygen consumption beyond the proximal tubule is mainly determined by active solute reabsorption, especially in the thick ascending limb of the Loop of Henle. Furosemide-induced suppression of oxygen consumption (FSOC) involves inhibition of sodium transport in this segment, which is normally accompanied by a marked decrease in the intrarenal deoxyhemoglobin detectable by blood oxygen level-dependent (BOLD)-magnetic resonance imaging (MRI). This study tested the hypothesis that the magnitude of BOLD-MRI signal change after furosemide is related to impaired renal function in renovascular hypertension. In 16 pigs with unilateral renal artery stenosis, renal hemodynamics, function, and tubular function (FSOC and fluid concentration capacity) were evaluated in both kidneys using MR and multidetector computerized tomography (MDCT) imaging. Animals with adequate FSOC (23.6 ± 2.2%, P > 0.05 vs. baseline) exhibited a mean arterial pressure (MAP) of 113 ± 7 mmHg, and relatively preserved glomerular filtration rate (GFR) of 60 ± 4.5 ml/min, comparable to their contralateral kidney (66 ± 4 ml/min, P > 0.05). In contrast, animals with low FSOC (3.1 ± 2.1%, P = NS vs. baseline) had MAP of 124 ± 9 mmHg and GFR (22 ± 6 ml/min) significantly lower than the contralateral kidneys (66 ± 4 ml/min, P < 0.05). The group with preserved GFR and FSOC showed an increase in intratubular fluid concentration as assessed by MDCT that was greater than that observed in the low GFR group, suggesting better preservation of tubular function in the former group. These results suggest that changes in BOLD-MRI after furosemide can differentiate between underperfused kidneys with preserved tubular function and those with tubular dysfunction. This approach may allow more detailed physiologic evaluation of poststenotic kidneys in renovascular hypertension than previously possible.

Unilateral renal artery stenosis (RAS) leads to atrophy of the stenotic kidney and compensatory enlargement of the contralateral kidney. Although the two-kidney, one-clip (2K1C) model has been extensively used to model human RAS, the cellular responses in the stenotic and contralateral kidneys, particularly in the murine model, have received relatively little attention. We studied mice 2, 5, and 11 wk after unilateral RAS. These mice became hypertensive within 1 wk. The contralateral kidney increased in size within 2 wk after surgery. This enlargement was associated with a transient increase in expression of phospho-extracellular signal-regulated kinase (p-ERK), the proliferation markers proliferating cell nuclear antigen and Ki-67, the cell cycle inhibitors p21 and p27, and transforming growth factor-β, with return to baseline levels by 11 wk. The size of the stenotic kidney was unchanged at 2 wk but progressively decreased between 5 and 11 wk. Unlike the contralateral kidney, which showed minimal histopathological alterations, the stenotic kidney developed progressive interstitial fibrosis, tubular atrophy, and interstitial inflammation. Surprisingly, the stenotic kidney showed a proliferative response, which involved largely tubular epithelial cells. The atrophic kidney had little evidence of apoptosis, despite persistent upregulation of p53; expression of cell cycle regulatory proteins in the stenotic kidney was persistently increased through 11 wk. These studies indicate that in the 2K1C model, the stenotic kidney and contralateral, enlarged kidney exhibit a distinct temporal expression of proteins involved in cell growth, cell survival, apoptosis, inflammation, and fibrosis. Notably, an unexpected proliferative response occurs in the stenotic kidney that undergoes atrophy.

Background Anesthetics administered to immature brains may cause histopathological changes and long-term behavioral abnormalities. The association between perinatal exposure to anesthetics during Cesarean delivery (CD) and development of learning disabilities (LD) was determined in a population-based birth cohort. Methods The educational and medical records of all children born to mothers residing in five townships of Olmsted County, Minnesota from 1976-1982 and remaining in the community at age 5 were reviewed to identify those with LDs. Cox proportional hazards regression was used to compare rates of LD between children delivered vaginally and via CD (with general or regional anesthesia). Results Of the 5,320 children in this cohort, 497 were delivered via CD (under general anesthesia n = 193, and regional anesthesia n = 304). The incidence of LD depended on mode of delivery (P = 0.050, adjusted for sex, birth weight, gestational age, exposure to anesthesia before age 4 yr, and maternal education). LD risk was similar in children delivered by vagina or CD with general anesthesia, but was reduced in children receiving CD with regional anesthesia (hazard ratio = 0.64, 95% confidence interval 0.44 to 0.92; P = 0.017 for comparison of CD under regional anesthesia compared to vaginal delivery). Conclusion Children exposed to general or regional anesthesia during CD are not more likely to develop LD compared to children delivered vaginally, suggesting that brief perinatal exposure to anesthetic drugs does not adversely affect long-term neurodevelopmental outcomes. The risk of LD may be lower in children delivered by CD whose mothers received regional anesthesia.

Background Abstinence from smoking can improve postoperative outcomes, and surgery is also an excellent opportunity for smokers to permanently quit. One strategy for perioperative tobacco interventions is that anesthesiologists Ask, Advise, and Refer (AAR) -- Ask their patients about tobacco use, Advise them to abstain, and Refer them to resources such as telephone quit-lines. This pilot project determined the feasibility and acceptability of the AAR strategy in anesthesiology practices. Methods An educational program, including presentations, written materials, and Web-based resources, was developed and disseminated to 14 U.S. anesthesiology practices, representing both academic and private practices, who agreed to implement the AAR strategy as a part of their routine clinical practice. Three months after implementation, a survey was administered to those members of these practices who were instructed in the AAR strategy. Results There were 97 respondents (75% response rate). Since the pilot project began, 91%, 79%, and 58% of respondents reported that they frequently or almost always asked, advised, and referred their patients who smoke, respectively. The majority of respondents (56%) agreed that they were responsible for helping patients get the help they need to quit smoking. Most (74%) also agreed that they planned to incorporate the AAR strategy into their routine practice. Conclusion These results suggest that the AAR strategy is potentially feasible and well-accepted in anesthesiology clinical practice. Further work will be needed to define whether these practices and attitudes can be sustained and whether they are ultimately effective in modifying perioperative smoking behavior in surgical patients.