Citations

Background A "teachable moment" is an event that motivates spontaneous behavior change. Some evidence suggests that major surgery for a smoking-related illness can serve as a teachable moment for smoking cessation. This study tested the hypotheses that surgery increases the likelihood of smoking cessation and that cessation is more likely after major surgical procedures compared with outpatient surgery. Methods Secondary analyses were performed of longitudinal biennial survey data (1992-2004) from the nationally representative Health and Retirement Study of U.S. adults older than 50 yr, determining the relationship between the incidence of smoking cessation and the occurrence of surgery. Results Five thousand four hundred ninety-eight individuals reported current smoking at enrollment, and 2,444 of them (44.5%) quit smoking during the period of examination. The incidence of quitting in smokers undergoing major surgery was 20.6/100 person-years of follow-up and 10.2/100 person-years in those undergoing outpatient surgery. In a multivariate negative binomial regression model, the incidence rate ratio of quitting associated with major surgery was 2.02 (95% CI: 1.67-2.44) and that of those associated with outpatient surgery was 1.28 (95% CI: 1.09-1.50). Estimates derived from national surgical utilization data show that approximately 8% of all quit events in the United States annually can be attributed to the surgical procedures analyzed. Conclusions Undergoing surgery is associated with an increased likelihood of smoking cessation in the older U.S. population. Cessation is more likely in association with major procedures compared with outpatient surgery. These data support the concept that surgery is a teachable moment for smoking cessation.

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.