Publications

OBJECTIVE

To evaluate contemporary national trends and outcomes of open pyeloplasty (OP) vs minimally invasive pyeloplasty (MIP) in the treatment of ureteropelvic junction obstruction using the National Surgical Quality Improvement Program database.

METHODS

Patients treated by OP or MIP between 2006 and 2011 were identified by The International Classification of Diseases, Ninth Revision, Clinical Modification codes corresponding to pyeloplasty as their primary operative procedure. Perioperative variables were analyzed using the chi-square and the Student t test. Multiple logistic regressions were used to identify morbidities and readmission risk factors.

RESULTS

Three hundred fifty-five patients were identified. Of them, 20.2% of cases were OP and 79.8% were MIP. There was a significant increase in MIP from 33% in 2006 to 83% in 2011 (P <.001). A total of 11.7% of patients in the MIP group underwent outpatient surgery (P = .002). Patients treated at a teaching hospital were over 3 times more likely to undergo MIP (odds ratio = 3.17; P = .001). There was significantly longer hospitalization in OP vs MIP (3.9 vs. 2.2 days; P = .001). OP was associated with significantly increased risk of reoperation or postoperative morbidity compared with MIP (11.1% vs. 4.2%; P = .02). Multivariate analysis confirmed a higher rate of overall morbidity in the OP cohort (P = .03). Male patients had significantly higher postoperative morbidity or reoperation rates (odds ratio = 4.38; P = .002). There was no significant difference in operative time between groups (P = .2).

CONCLUSION

Within the American College of Surgeons National Surgical Quality Improvement Program hospitals, MIP is associated with decreased reoperation and postoperative morbidity compared with OP.

IMPORTANCE

There is a paucity of data assessing the effect of increased surgical duration on the incidence of venous thromboembolism (VTE).

OBJECTIVE

To examine the association between surgical duration and the incidence of VTE.

DESIGN, SETTINGS, AND PARTICIPANTS

Retrospective cohort of 1,432,855 patients undergoing surgery under general anesthesia at 315 US hospitals participating in the American College of Surgeons National Surgical Quality Improvement Program from 2005 to 2011.

EXPOSURE

Duration of surgery.

MAIN OUTCOMES AND MEASURES

The rates of deep vein thrombosis (DVT), pulmonary embolism (PE), and VTE within 30 days of the index operation. Surgical duration was standardized across Current Procedural Terminology codes using a z score. Outcomes were compared across quintiles of the z score. Multiple logistic regression models were developed to examine the association while adjusting for patient demographics, clinical characteristics, and comorbidities.

RESULTS

The overall VTE rate was 0.96% (n = 13,809); the rates of DVT and PE were 0.71% (n = 10,198) and 0.33% (n = 4772), respectively. The association between surgical duration and VTE increased in a stepwise fashion. Compared with a procedure of average duration, patients undergoing the longest procedures experienced a 1.27-fold (95% CI, 1.21-1.34; adjusted risk difference [ARD], 0.23%) increase in the odds of developing a VTE; the shortest procedures demonstrated an odds ratio of 0.86 (95% CI, 0.83-0.88; ARD, -0.12%). The robustness of these results was substantiated with several sensitivity analyses attempting to minimize the effect of outliers, concurrent complications, procedural differences, and unmeasured confounding variables.

CONCLUSIONS AND RELEVANCE

Among patients undergoing surgery, an increase in surgical duration was directly associated with an increase in the risk for VTE. These findings may help inform preoperative and postoperative decision making related to surgery.

Macrostructures based on natural polymers are subject to large attention, as the application range is wide within the food and pharmaceutical industries. In this study we present nanocomplexes (NCXs) made from electrostatic self-assembly between negatively charged alginate and positively charged fish sarcoplasmic proteins (FSP), prepared by bulk mixing. A concentration screening revealed that there was a range of alginate and FSP concentrations where stable NCXs with similar properties were formed, rather than two exact concentrations. The size of the NCXs was 293 ± 3 nm, and the zeta potential was -42 ± 0.3 mV. The NCXs were stable in water, gastric buffer, intestinal buffer and HEPES buffered glycose, and at all pH values from 2 to 9 except pH 3, where they aggregated. When proteolytic enzymes were present in the buffer, the NCXs were degraded. Only at high concentrations the NCXs caused a decreased viability in HeLa and U2OS cell lines. The simple processing procedure and the high stability of the NCXs, makes them excellent candidates for use in the food and pharmaceutical industry.