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Objectives

Understanding the factors contributing to improved postoperative patient outcomes remains paramount. For complex abdominal operations such as pancreaticoduodenectomy (PD), the influence of provider and hospital volume on surgical outcomes has been described. The impact of resident experience is less well understood.

Methods

We reviewed perioperative outcomes after PD at a single high-volume center between 2006 and 2012. Resident participation and outcomes were collected in a prospectively maintained database. Resident experience was defined as postgraduate year (PGY) and number of PDs performed.

Results

Forty-three residents and four attending surgeons completed 686 PDs. The overall complication rate was 44 %; PD-specific complications (defined as pancreatic fistula, delayed gastric emptying, intraabdominal abscess, wound infection, and bile leak) occurred in 28 % of patients. The overall complication rates were similar when comparing PGY 4 to PGY 5 residents (55.3 vs. 43.0 %; p?>?0.05). On univariate analysis, there was a difference in PD-specific complications seen between a PGY 4 as compared to a PGY 5 resident (44 vs. 27 %, respectively; p?=?0.016). However, this was not statistically significant when adjusted for attending surgeon. Logistic regression demonstrated that as residents perform more cases, PD-specific complications decrease (OR?=?0.97; p?<?0.01). For a resident's first PD case, the predicted probability of a PD-specific complication is 27 %; this rate decreases to 19 % by resident case number 15.

Conclusions

Complex cases, such as PD, provide unparalleled learning opportunities and remain an important component of surgical training. We highlight the impact of resident involvement in complex abdominal operations, demonstrating for the first time that as residents build experience with PD, patient outcomes improve. This is consistent with volume–outcome relationships for attending physicians and high-volume hospitals. Maximizing resident repetitive exposure to complex procedures benefits both the patient and the trainee.  相似文献   
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BACKGROUND: Clinical assessment of vitamin D status often relies on measuring total circulating 25-hydroxyvitamin D3 (25OHD3), but much of each vitamin D metabolite is bound to plasma vitamin D-binding protein (DBP), such that the percentage of free vitamin is very low. We hypothesized that measurement of free rather than total 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and 25OHD3 may provide better assessment of vitamin D status. We therefore aimed to assess vitamin D status in men with idiopathic osteoporosis, in whom possible secondary causes of osteoporosis had been excluded, and to determine the extent of change in biologically active "free" vitamin D caused by variation in plasma DBP concentrations. METHODS: We measured 1,25(OH)2D3 and 25OHD3 in plasma samples from 56 men with idiopathic osteoporosis [mean (SD) age, 59.6 (13.6) years; range, 21-86 years] and 114 male controls [62.4 (10.4) years; range, 44-82 years]. RESULTS: Mean total plasma 25OHD3 in the 56 men with osteoporosis and the 114 controls was 44.7 (21) and 43.3 (17) nmol/L, respectively; total plasma 1,25(OH)2D3 measured in randomly selected men with osteoporosis (n = 50) and controls (n = 50) was 90 (37) and 103 (39) pmol/L, respectively. Mean plasma DBP was significantly higher (P <0.001) in men with osteoporosis [224 (62) mg/L; n = 56] than in the controls [143 (34) mg/L; n = 114], but calculated free plasma 25OHD3 and 1,25(OH)2D3 were significantly lower in the osteoporotic men than in controls [6.1 (3.1) vs 9.1 (4.4) pmol/L (P <0.00001) and 77 (37) vs 142 (58) fmol/L (P <0.00001), respectively]. CONCLUSIONS: Measurement of total vitamin D metabolites alone, although providing a crude assessment of vitamin D status, may not give an accurate indication of the free (biologically active) form of the vitamin. The ratio of total 25OHD3 and 1,25(OH)2D3 to plasma DBP, rather than total circulating vitamin D metabolites, may provide a more useful index of biological activity. Further studies are required to substantiate this hypothesis.  相似文献   
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Antioxidant status in rheumatoid arthritis and role of antioxidant therapy   总被引:7,自引:0,他引:7  
BACKGROUND: Oxygen free radicals have been implicated as mediators of tissue damage in patients of rheumatoid arthritis (RA). This study was designed to elucidate plasma oxidant/antioxidant status in rheumatoid arthritis, with the aim of evaluating the importance of antioxidant therapy in the management of this disease. METHODS: The study included 40 patients of rheumatoid arthritis who were randomly divided into two subgroups of 20 each. One group received conventional treatment for 12 weeks and in the other group conventional treatment was supplemented with antioxidants for the same duration. Twenty age- and sex-matched normal individuals constituted the control group. Blood samples of controls and patients were collected at the time of presentation and analyzed for total thiols, glutathione, vitamin C and malondialdehyde (MDA-marker of oxidative stress). The investigations were repeated in the patients after 12 weeks. RESULTS: The blood concentrations of total thiols, glutathione and vitamin C were found to be significantly lower in rheumatoid arthritis patients as compared to healthy controls, while the concentrations of MDA were much higher. There was a statistically significant increase in the posttreatment concentrations of these antioxidants, along with a decrease in the concentrations of MDA. CONCLUSIONS: The antioxidant defense system is compromised in rheumatoid arthritis patients. There is a shift in the oxidant/antioxidant balance in favor of lipid peroxidation, which could lead to the tissue damage observed in the disease. The results suggest the necessity for therapeutic co-administration of antioxidants along with conventional drugs to such patients. However, due to the limited number of cases included in this study, more studies may be required to substantiate the results and arrive at a definite conclusion, in terms of safety and efficacy of adding on antioxidant therapy for the treatment of RA.  相似文献   
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