BACKGROUND
Accurately estimating surgical risks is critical for shared decision making and informed consent. The Centers for Medicare and Medicaid Services may soon put forth a measure requiring surgeons to provide patients with patient-specific, empirically-derived estimates of postoperative complications. Our objectives were (1) to develop a universal surgical risk estimation tool, (2) to compare performance of the universal vs. prior procedure-specific Surgical Risk Calculators, and (3) to allow surgeons to empirically adjust the estimates of risk.
STUDY DESIGN
Using standardized clinical data from 393 ACS NSQIP hospitals, a web-based tool was developed to allow surgeons to easily enter 21 preoperative factors (demographics, comorbidities, procedure). Regression models were developed to predict 8 outcomes based on the preoperative risk factors. The universal model was compared to procedure-specific models. To incorporate surgeon input, a subjective Surgeon Adjustment Score, allowing risk estimates to vary within the estimate's confidence interval, was introduced and tested with 80 surgeons using 10 case scenarios.
RESULTS
Based on 1,414,006 patients encompassing 1,557 unique CPT codes, a universal Surgical Risk Calculator model was developed which had excellent performance for mortality (c-statistic=0.944; Brier=0.011[ where scores approaching zero are better]), morbidity (c-statistic=0.816, Brier=0.069), and 6 additional complications (c-statistics>0.8). Predictions were similarly robust for the universal calculator vs. procedure-specific calculators (e.g., colorectal). Surgeons demonstrated considerable agreement on the case scenario scoring (80-100% agreement), suggesting reliable score assignment between surgeons.
CONCLUSIONS
The ACS NSQIP Surgical Risk Calculator is a decision-support tool based on reliable multi-institutional clinical data which can be used to estimate the risks of most operations. The ACS NSQIP Surgical Risk Calculator will allow clinicians and patients to make decisions using empirically derived, patient-specific postoperative risks.
The role of cytosolic calcium oscillation has long been recognized in the regulation of cellular and molecular interactions. Information embedded in calcium oscillation can provide molecular cues for cell behavior such as cell differentiation. Although calcium dynamics are versatile and likely to depend on the cell type, the calcium dynamics in human mesenchymal stem cells (hMSCs) and its role in differentiation are yet to be fully elucidated. In the present study we characterized the calcium oscillation profiles in hMSCs before and after subjecting the cells to the osteoinductive factors. Our findings indicate that the calcium spikes decreased rapidly with osteodifferentiation to a level observed in terminally differentiated human osteoblasts. In addition, the calcium oscillations appear to serve as a bidirectional signal during hMSC differentiation. While an altered calcium oscillation pattern may be an indicator for hMSC differentiation, it is also likely to be involved in directing hMSC differentiation. Treatment of hMSCs with a noninvasive electrical stimulation, for example, not only altered the calcium oscillations but also facilitated osteodifferentiation. Regulation of calcium oscillation by external physical stimulation could amplify hMSC differentiation into a tissue-specific lineage and may offer an alternate biotechnology to harness the unique properties of stem cells.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.