Suppressed basal melting in the eastern Thwaites Glacier grounding zone.

Thwaites Glacier is one of the fastest-changing ice-ocean systems in Antarctica1-3. Much of the ice sheet within the catchment of Thwaites Glacier is grounded below sea level on bedrock that deepens inland4, making it susceptible to rapid and irreversible ice loss that could raise the global sea level by more than half a metre2,3,5. The rate and extent of ice loss, and whether it proceeds irreversibly, are set by the ocean conditions and basal melting within the grounding-zone region where Thwaites Glacier first goes afloat3,6, both of which are largely unknown. Here we show-using observations from a hot-water-drilled access hole-that the grounding zone of Thwaites Eastern Ice Shelf (TEIS) is characterized by a warm and highly stable water column with temperatures substantially higher than the in situ freezing point. Despite these warm conditions, low current speeds and strong density stratification in the ice-ocean boundary layer actively restrict the vertical mixing of heat towards the ice base7,8, resulting in strongly suppressed basal melting. Our results demonstrate that the canonical model of ice-shelf basal melting used to generate sea-level projections cannot reproduce observed melt rates beneath this critically important glacier, and that rapid and possibly unstable grounding-line retreat may be associated with relatively modest basal melt rates.

Initiating statistical process control to improve quality outcomes in colorectal surgery.

BACKGROUND: Unexpected variations in postoperative length of stay (LOS) negatively impact resources and patient outcomes. Statistical process control (SPC) measures performance, evaluates productivity, and modifies processes for optimal performance. The goal of this study was to initiate SPC to identify LOS outliers and evaluate its feasibility to improve outcomes in colorectal surgery. METHODS: Review of a prospective database identified colorectal procedures performed by a single surgeon. Patients were grouped into elective and emergent categories and then stratified by laparoscopic and open approaches. All followed a standardized enhanced recovery protocol. SPC was applied to identify outliers and evaluate causes within each group. RESULTS: A total of 1294 cases were analyzed--83% elective (n = 1074) and 17% emergent (n = 220). Emergent cases were 70.5% open and 29.5% laparoscopic; elective cases were 36.8% open and 63.2% laparoscopic. All groups had a wide range in LOS. LOS outliers ranged from 8.6% (elective laparoscopic) to 10.8% (emergent laparoscopic). Evaluation of outliers demonstrated patient characteristics of higher ASA scores, longer operating times, ICU requirement, and temporary nursing at discharge. Outliers had higher postoperative complication rates in elective open (57.1 vs. 20.0%) and elective lap groups (77.6 vs. 26.1%). Outliers also had higher readmission rates for emergent open (11.4 vs. 5.4%), emergent lap (14.3 vs. 9.2%), and elective lap (32.8 vs. 6.9%). Elective open outliers did not follow trends of longer LOS or higher reoperation rates. CONCLUSIONS: SPC is feasible and promising for improving colorectal surgery outcomes. SPC identified patient and process characteristics associated with increased LOS. SPC may allow real-time outlier identification, during quality improvement efforts, and reevaluation of outcomes after introducing process change. SPC has clinical implications for improving patient outcomes and resource utilization.

Prone jackknife position is not necessary to achieve a cylindrical abdominoperineal resection: demonstration of the lithotomy position.

This video demonstrates a laparoscopic abdominal perineal resection for a fixed 4.8-cm mass involving the posterior and left rectal walls and left puborectalis, 2 cm from the anal verge (see Video, Supplemental Digital Content 1, http://links.lww.com/DCR/A127). We detail the steps of the procedure, all completed in lithotomy, including lateral-to-medial dissection; identification and protection of the left ureter and presacral nerves; division of the inferior mesenteric artery; medial-to-lateral dissection, with meeting the previous dissection plane; total mesorectal excision and pelvic dissection; perineal dissection and layered closure; and abdominal inspection and colostomy creation. Total operative time was 181 minutes. The specimen total mesorectal excision was complete with a negative circumferential radial margin (greater than 1 cm). Final pathology was T3N2M0.

Process control to measure process improvement in colorectal surgery: modifications to an established enhanced recovery pathway.

BACKGROUND: After more than a decade of improvement, our enhanced recovery pathway had patients who had undergone laparoscopic colectomy going home a mean 3.7 days postoperatively. We wondered if adding a transverse abdominus plane block and intravenous acetaminophen to an established pathway would improve outcomes and resource use. OBJECTIVE: The aim of this study was to evaluate the impact of modification of an enhanced recovery pathway on patient outcomes. DESIGN: This was a case-matched study. METHODS: After the addition of transverse abdominus plane blocks and acetaminophen to the enhanced recovery pathway 12 months ago, review of a prospective database was performed. Patients were matched by procedure type, age, and sex. SETTINGS: This study was performed at a tertiary referral center. PATIENTS: Patients undergoing elective major laparoscopic colorectal surgery from 2010 to 2012 were included. MAIN OUTCOME MEASURES: The primary outcome measures were hospital length of stay, readmission rate, postoperative complications, and the cost of the hospital episode before and after the amendment of our enhanced recovery pathway. RESULTS: Two hundred eight elective major laparoscopic cases were evaluated. Both groups were similar in demographics and comorbidities. Length of stay was significantly shorter once transverse abdominus plane blocks and acetaminophen were introduced (p < 0.01), dropping from 3.7 to 2.6 days. There were significantly more complications in the prechange group (p = 0.02), but no significant differences in readmissions or mortality. Direct costs were similar, but there was a $500 increase in total margin per case (p = 0.004) with the pathway changes. With the use of statistical process control to examine the effect on outliers, there was significantly less variation in the mean length of stay (2.29 vs 1.90 days, p < 0.01) after the addition of transverse abdominus plane blocks and intravenous acetaminophen. LIMITATIONS: The single-surgeon, single-institution design was a limitation of this study. CONCLUSIONS: The addition of a transverse abdominus plane block and acetaminophen significantly reduced length of stay more than that seen with a previously established pathway. Statistical process control demonstrated that our pathway changes significantly reduced the spread of outliers around our mean length of stay.

Comparative effectiveness of laparoscopic versus robot-assisted colorectal resection.

BACKGROUND: During the past 20 years, laparoscopy has revolutionized colorectal surgery. With proven benefits in patient outcomes and healthcare utilization, laparoscopic colorectal surgery has steadily increased in use. Robotic surgery, a new addition to colorectal surgery, has been suggested to facilitate and overcome limitations of laparoscopic surgery. Our objective was to compare the outcomes of robot-assisted laparoscopic resection (RALR) to laparoscopic resections (LAP) in colorectal surgery. METHODS: A national inpatient database was evaluated for colorectal resections performed over a 30-month period. Cases were divided into traditional LAP and RALR resection groups. Cost of robot acquisition and servicing were not measured. Main outcome measures were hospital length of stay (LOS), operative time, complications, and costs between groups. RESULTS: A total of 17,265 LAP and 744 RARL procedures were identified. The RALR cases had significantly higher total cost ($5,272 increase, p < 0.001) and direct cost ($4,432 increase, p < 0.001), significantly longer operating time (39 min, p < 0.001), and were more likely to develop postoperative bleeding (odds ratio 1.6; p = 0.014) than traditional laparoscopic patients. LOS, complications, and discharge disposition were comparable. Similar findings were noted for both laparoscopic colonic and rectal surgery. CONCLUSIONS: RALR had significantly higher costs and operative time than traditional LAP without a measurable benefit.

Tolerance values of benthic macroinvertebrates for stream biomonitoring: assessment of assumptions underlying scoring systems worldwide.

Tolerance values (TVs) based on benthic macroinvertebrates are one of the most widely used tools for monitoring the biological impacts of water pollution, particularly in streams and rivers. We compiled TVs of benthic macroinvertebrates from 29 regions around the world to test 11 basic assumptions about pollution tolerance, that: (1) Arthropoda are < tolerant than non-Arthropoda; (2) Insecta < non-Insecta; (3) non-Oligochaeta < Oligochaeta; (4) other macroinvertebrates < Oligochaeta + Chironomidae; (5) other macroinvertebrate taxa < Isopoda + Gastropoda + Hirudinea; (6) Ephemeroptera + Plecoptera + Trichoptera (EPT) < Odonata + Coleoptera + Heteroptera (OCH); (7) EPT < non-EPT insects; (8) Diptera < Insecta; (9) Bivalvia < Gastropoda; (10) Baetidae < other Ephemeroptera; and (11) Hydropsychidae < other Trichoptera. We found that the first eight of these 11 assumptions were supported despite regional variability. In addition, we examined the effect of Best Professional Judgment (BPJ) and non-independence of TVs among countries by performing all analyses using subsets of the original dataset. These subsets included a group based on those systems using TVs that were derived from techniques other than BPJ, and groups based on methods used for TV assignment. The results obtained from these subsets and the entire dataset are similar. We also made seven a priori hypotheses about the regional similarity of TVs based on geography. Only one of these was supported. Development of TVs and the reporting of how they are assigned need to be more rigorous and be better described.

Economic and ecological costs and benefits of streamflow augmentation using recycled water in a California coastal stream.

Streamflow augmentation has the potential to become an important application of recycled water in water scarce areas. We assessed the economic and ecological merits of a recycled water project that opted for an inland release of tertiary-treated recycled water in a small stream and wetland compared to an ocean outfall discharge. Costs for the status-quo scenario of discharging secondary-treated effluent to the ocean were compared to those of the implemented scenario of inland streamflow augmentation using recycled water. The benefits of the inland-discharge scenario were greater than the increase in associated costs by US$1.8M, with recreational value and scenic amenity generating the greatest value. We also compared physical habitat quality, water quality, and benthic macroinvertebrate community upstream and downstream of the recycled water discharge to estimate the effect of streamflow augmentation on the ecosystem. The physical-habitat quality was higher downstream of the discharge, although streamflow came in unnatural diurnal pulses. Water quality remained relatively unchanged with respect to dissolved oxygen, pH, and ammonia-nitrogen, although temperatures were elevated. Benthic macroinvertebrates were present in higher abundances, although the diversity was relatively low. A federally listed species, the California red-legged frog (Rana draytonii), was present. Our results may support decision-making for wastewater treatment alternatives and recycled water applications in Mediterranean climates.

Optimizing cost and short-term outcomes for elderly patients in laparoscopic colonic surgery.

BACKGROUND: Elderly patients often are regarded as high-risk for major abdominal surgery because of a lack of functional reserve and associated medical comorbidities. The goal of this study was to compare the cost of care and short-term outcomes of elderly and nonelderly patients undergoing laparoscopic colectomy. Our hypothesis was that elderly patients managed with laparoscopic colorectal surgery and an enhanced recovery protocol (ERP) can realize the same benefits of lower hospital length of stay (LOS) without increasing hospital costs or readmission rates. METHODS: Review of a prospective database identified all patients that underwent an elective laparoscopic colectomy from 2009 to 2012. Patients were stratified into elderly (≥70 years old) and nonelderly (<70 years old) cohorts. The main outcome measures were discharge disposition, hospital costs, hospital LOS, and 30-day readmission rates between the laparoscopic and open groups. RESULTS: A total of 302 nonelderly (66%) and 153 elderly (34%) patients were included in the analysis. The elderly cohort had significantly higher comorbidities than the nonelderly group. There were no mortalities. Operative variables (procedure time, blood loss, and intraoperative complications) were similar. At discharge, significantly more elderly patients required temporary nursing or home care. There were no significant differences in short-term outcomes of LOS, 30-day readmission rates, or costs for the episode of care between the two groups. CONCLUSIONS: Combining laparoscopic colectomy with an ERP is cost-effective and results in similar short-term outcomes for the elderly and nonelderly patients. Despite higher comorbidities, elderly patients realized the same benefits of shorter LOS with similar hospital costs and readmission rates.

Integrating hospital administrative data to improve health care efficiency and outcomes: "the socrates story".

Evaluation of health care outcomes has become increasingly important as we strive to improve quality and efficiency while controlling cost. Many groups feel that analysis of large datasets will be useful in optimizing resource utilization; however, the ideal blend of clinical and administrative data points has not been developed. Hospitals and health care systems have several tools to measure cost and resource utilization, but the data are often housed in disparate systems that are not integrated and do not permit multisystem analysis. Systems Outcomes and Clinical Resources AdministraTive Efficiency Software (SOCRATES) is a novel data merging, warehousing, analysis, and reporting technology, which brings together disparate hospital administrative systems generating automated or customizable risk-adjusted reports. Used in combination with standardized enhanced care pathways, SOCRATES offers a mechanism to improve the quality and efficiency of care, with the ability to measure real-time changes in outcomes.

Simulation and its role in training.

Despite its short history, surgical simulation has been successfully introduced into surgical residency programs in an effort to augment training. A wide range of simulator types and levels of complexity have proven an effective teaching method for surgical trainees. They have been used for training in areas such as general surgery, urology, gynecology, and ophthalmology among others. Coincident with the introduction of simulators is the need for objective evaluation of skills learned on them, which has led to the development and validation of multiple evaluation tools. This article evaluates the drivers for simulation, types of simulators, training, and evaluation of them especially as it pertains to laparoscopic colorectal surgery.