Diagnosis of sepsis from a drop of blood by measurement of spontaneous neutrophil motility in a microfluidic assay.

Current methods for the diagnosis of sepsis have insufficient precision, causing regular misdiagnoses. Microbiological tests can help diagnose sepsis but are usually too slow to have an impact on timely clinical-decision making. Neutrophils have high sensitivity to infections, yet measurements of neutrophil surface markers, genomic changes, and phenotype alterations have had only a marginal effect on sepsis diagnosis. Here, we report a microfluidic assay that measures the spontaneous motility of neutrophils in the context of plasma, in one droplet of blood. We measured the performance of the assay in two independent cohorts of critically ill patients suspected of sepsis. In the first cohort, we developed a machine-learning-based scoring system (sepsis score) that segregated patients with sepsis from those without sepsis. In the second cohort, we validated the sepsis score in a double-blinded, prospective case-control study. For the 42 patients across the two cohorts, the assay identified sepsis patients with 97% sensitivity and 98% specificity. The neutrophil assay could potentially be used to accurately diagnose and monitor sepsis in larger populations of at-risk patients.

High-Fidelity Emergency Department Thoracotomy Simulator With Beating-Heart Technology and OSATS Tool Improves Trainee Confidence and Distinguishes Level of Skill.

OBJECTIVE: Resuscitative Thoracotomy or Emergency Department Thoracotomy (EDT) is a time-sensitive and potentially life-saving procedure. Yet, trainee experience with this procedure is often limited in both clinical and simulation settings. We sought to develop a high-fidelity EDT simulation module and assessment tool to facilitate trainee education. DESIGN: Using the Kern model for curricular development, a group of expert trauma surgeons identified EDT as a high-stakes, low-frequency procedure. Task analysis identified 5 key steps of EDT: (1) opening chest/rib spreader utilization; (2) pericardiotomy/cardiac repair; (3) open cardiac massage; (4) clamping aorta; and (5) control of pulmonary hilum. A high-fidelity simulator with beating-heart technology was built. The previously validated Objective Structured Assessment of Technical Skills (OSATS) was adapted to create the "EDT-OSATS" which assessed performance along several domains: (1) Surgical technique (key steps); (2) general skills; and (3) global rating. A pilot test was performed to compare board-certified trauma surgeons (i.e., Experts) with categorical general surgery interns (i.e., Novices). Each subject received preparatory materials, completed a presimulation quiz, performed a videotaped procedure on the EDT simulator, and completed a postmodule survey. Two independent raters scored performances using the EDT-OSATS. Groups were compared in descriptive and unadjusted analyses. We hypothesized that our EDT simulation module would distinguish between expert vs novice performance and improve trainee confidence. SETTING: Simulation laboratory at Massachusetts General Hospital in Boston, MA. PARTICIPANTS: Trauma surgeons (Experts, n = 6) and categorical general surgery interns (Novices, n = 8). RESULTS: Experts scored significantly higher than Novices on nearly all components of the EDT-OSATS, including: (1) surgical technique: pericardiotomy (4.2 vs 3.4, p = 0.040), cardiac massage (3.6 vs 2.4, p = 0.028), clamping aorta (4.1 vs 3.3, p = 0.035), control of pulmonary hilum (4.8 vs 3.4, p < 0.001); (2) general skills: time/motion (4.1 vs 2.9, p = 0.011), knowledge and handling of instruments (4.3 vs 3.1, p = 0.004), and (3) global rating (3.9 vs 2.9, p = 0.026). There was no statistical difference between groups on opening chest/rib spreader utilization (3.8 vs 3.3, p = 0.352) or procedure time (204sec vs 227sec, p = 0.401), though Experts scored numerically higher than Novices on every measure. Novices reported significantly increased confidence after the simulation (3.1 vs 1.4, p = 0.001). Ninety-three percent (13/14) of participants found the simulator realistic. CONCLUSIONS: Our novel high-fidelity beating-heart EDT simulator is realistic and improves trainee confidence in this low-frequency, high-stakes emergency procedure. The EDT-OSATS tool differentiates between performances of experienced surgeons vs novice trainees on the beating-heart simulator. This training module and accompanying assessment instrument hold promise as a learning tool for clinicians who may perform emergency department thoracotomy.

Early Protein Inadequacy Is Associated With Longer Intensive Care Unit Stay and Fewer Ventilator-Free Days: A Retrospective Analysis of Patients With Prolonged Surgical Intensive Care Unit Stay.

BACKGROUND: Failure to provide adequate nutrition in the intensive care unit (ICU) may be particularly harmful for patients with prolonged critical illness. We hypothesized that early nutrition inadequacy is more influential for those requiring a longer ICU stay versus those requiring a shorter stay. METHODS: We enrolled 280 adult patients with prolonged surgical ICU stay who were receiving enteral nutrition for >72 hours. Subjects were divided into 2 groups: shortICU (<14 days) and longICU (≥14 days). Nutrition deficits at ICU days 3 and 7 were calculated. To investigate whether early nutrient deficit was associated with ICU length of stay (LOS), hospital LOS, 28-day ventilator-free days, and discharge disposition (home/rehabilitation vs death/nursing home), we performed linear and logistic regression analyses controlling for age, sex, body mass index, and APACHE II (Acute Physiology and Chronic Health Evaluation). RESULTS: While the shortICU (n = 163) and longICU (n = 117) groups were similar in age, APACHE II, Injury Severity Score, energy/protein prescription, and enteral nutrition initiation within 48 hours, the longICU group was more commonly male (76% vs 61%, P = .007) and had higher body mass index (27.4 vs 25.6, P = .007). Significant interactions occurred: in the longICU group but not the shortICU group, protein deficits were associated with longer ICU stay and fewer 28-day ventilator-free days. CONCLUSIONS: Early protein deficits accumulating at ICU days 3 and 7 are associated with worse clinical outcomes among patients requiring longer ICU stays. Additional studies are required to confirm these findings.

Resolvin D2 Limits Secondary Tissue Necrosis After Burn Wounds in Rats.

Secondary burn necrosis is the expansion and deepening of the original burn injury several days after injury. Limiting the extent of secondary burn necrosis may improve outcomes. In this study, we examined the ability of the lipid mediator of inflammation-resolution resolvin D2 (RvD2) and chromatin-lysing enzyme (DNase) to reduce secondary burn necrosis. Male Wistar rats were injured using a brass comb with 4 prongs heated in boiling water. This method created 2 parallel rows of 4 rectangular burned areas separated by 3 unburned interspaces. Starting at 2 hours after the burn injury, rats received either 25 ng/kg RvD2 intravenously daily for 7 days or 200 U/kg DNase every 12 hours for 3 days. We documented the necrosis around the initial wounds by digital photography. We used laser Doppler to assess the total blood flux in the burn area. We evaluated the functionality of the capillary network in the interspaces by optical coherence tomography angiography. We performed histological examination of wound skin tissue samples collected at 14 days postburn. We found that the interspace areas were preserved and had higher blood flow in the RvD2-treated group, while the burn areas expanded into the interspace areas, which were confluent by 7 days postburn, in the control-untreated group. We found a larger monocyte-to-neutrophil ratio in the RvD2-treated group compared with the DNase-treated and control groups (P < .05). Overall, RvD2 suppresses secondary necrosis and starts regeneration, highlighting the role of inflammation resolution as a potential therapeutic target in burn care.

Elevated admission N-terminal pro-brain natriuretic peptide level predicts the development of atrial fibrillation in general surgical intensive care unit patients.

BACKGROUND: New onset atrial fibrillation (AF) in critically ill surgical patients is associated with significant morbidity and increased mortality. N-terminal pro-B type natriuretic peptide (NT-proBNP) is released by cardiomyocytes in response to stress and may predict AF development after surgery. We hypothesized that elevated NT-proBNP level at surgical intensive care unit (ICU) admission predicts AF development in a general surgical and trauma population. METHODS: From July to October 2015, NT-proBNP concentrations were measured at ICU admission. Abnormal NT-proBNP concentrations were defined by age-adjusted cut-offs. We examined the relationship between the development of AF and demographics, clinical variables, and NT-proBNP level using univariate analysis and a multivariable logistic regression model. RESULTS: Three hundred eighty-seven subjects were included in the cohort, none of whom were in AF at ICU admission. The median age was 63 years (52-73 years), and 40.3% were women. The risk of developing AF was higher for abnormal versus normal NT-proBNP (22% vs. 4%; p < 0.0001). Using optimal derived cutoffs (regardless of age), the risk of developing AF was 2% for NT-proBNP less than 600 ng/L, 15% for NT-proBNP of 600 ng/L to 1,999 ng/L, and 27% for NT-proBNP of 2,000 ng/L or greater. Multiple logistic regression analysis identified three independent predictors for new-onset AF: age, older than 70 years (odds ratio [OR], 3.7, 95% confidence interval [CI], 1.5-9.3), history of AF (OR, 25.3; 95% CI, 9.6-67.0), and NT-proBNP of 600 or greater (OR, 4.3; 95% CI, 1.3-14.2). When none or only one predictor was present, AF incidence was less than 1%. When all three predictors were present, AF incidence was 66%. For subjects 70 years or older but no history of AF, AF incidence was 12.8% when NT-proBNP was 600 or greater compared with 0% when NT-proBNP was less than 600. For subjects younger than 70 years with a history of AF, AF incidence was 44.4% when NT-proBNP was 600 or higher compared to 0% when NT-proBNP was less than 600. CONCLUSION: Elevated NT-proBNP at ICU admission in general surgical and trauma patients is predictive of AF development in the first 3 ICU days. Addition of NT-proBNP measurement to known risk factors can improve predictive power and identify patients who might potentially benefit from evidence-based prophylactic treatment for AF.

Hypophosphatemia in Enterally Fed Patients in the Surgical Intensive Care Unit.

INTRODUCTION: Hypophosphatemia has been associated with refeeding malnourished patients, but its clinical significance is unclear. We investigated the incidence of refeeding hypophosphatemia (RH) in the surgical intensive care unit (SICU) and its association with early enteral nutrition (EN) administration and clinical outcomes. METHODS: We performed a retrospective review of a 2-year database of patients receiving EN in the SICU. RH was defined as a post-EN phosphorus (PHOS) level decrement of >0.5 mg/dL to a nadir <2.0 mg/dL within 8 days from EN initiation. We investigated the risk factors for RH and examined its association with clinical outcomes using multivariable regression analyses. RESULTS: In total, 213 patients comprised our analytic cohort. Eighty-three of 213 (39%) individuals experienced RH and 43 of 130 (33%) of the remaining patients experienced non-RH hypophosphatemia (nadir PHOS level <2.0 mg/dL). Overall, there was a total 59% incidence of hypophosphatemia of any cause (N = 126). Nutrition parameters did not differ between groups; most patients were initiated on EN within 48 hours of SICU admission, and timing of EN initiation was not a significant predictor for the development of RH. The median hospital length of stay (LOS) was 21 and 24 days for those with and without RH, respectively ( P = .79); RH remained a nonsignificant predictor for hospital LOS in the multivariable analysis. CONCLUSIONS: RH is common in the SICU but is not related to timing or amount of EN. Hypophosphatemia is also common in the critically ill, but regardless of etiology, it was not found to be a predictor of worse clinical outcomes.

Cervical spine MRI in patients with negative CT: A prospective, multicenter study of the Research Consortium of New England Centers for Trauma (ReCONECT).

BACKGROUND: Although cervical spine CT (CSCT) accurately detects bony injuries, it may not identify all soft tissue injuries. Although some clinicians rely exclusively on a negative CT to remove spine precautions in unevaluable patients or patients with cervicalgia, others use MRI for that purpose. The objective of this study was to determine the rates of abnormal MRI after a negative CSCT. METHODS: Blunt trauma patients who either were unevaluable or had persistent midline cervicalgia and underwent an MRI of the C-spine after a negative CSCT were enrolled prospectively in eight Level I and II New England trauma centers. Demographics, injury patterns, CT and MRI results, and any changes in cervical spine management as a result of MRI imaging were recorded. RESULTS: A total of 767 patients had MRI because of cervicalgia (43.0%), inability to evaluate (44.1%), or both (9.4%). MRI was abnormal in 23.6% of all patients, including ligamentous injury (16.6%), soft tissue swelling (4.3%), vertebral disc injury (1.4%), and dural hematomas (1.3%). Rates of abnormal neurological signs or symptoms were not different among patients with normal versus abnormal MRI. (15.2 vs. 18.8%, p = 0.25). The c-collar was removed in 88.1% of patients with normal MRI and 13.3% of patients with an abnormal MRI. No patient required halo placement, but 11 patients underwent cervical spine surgery after the MRI results. Six of the eleven had neurological signs or symptoms. CONCLUSIONS: In a select population of patients, MRI identified additional injuries in 23.6% of patients despite a normal CSCT. It is uncertain if this is a true limitation of CT technology or represents subtle injuries missed in the interpretation of the scan. The clinical significance of these abnormal MRI findings cannot be determined from this study group. LEVEL OF EVIDENCE: Therapeutic study, level IV.

Hypophosphatemia in Enterally Fed Patients in the Surgical Intensive Care Unit: Common but Unrelated to Timing of Initiation or Aggressiveness of Nutrition Delivery.

INTRODUCTION: Hypophosphatemia has been associated with refeeding malnourished patients, but its clinical significance is unclear. We investigated the incidence of refeeding hypophosphatemia (RH) in the surgical intensive care unit (SICU) and its association with early enteral nutrition (EN) administration and clinical outcomes. METHODS: We performed a retrospective review of a 2-year database of patients receiving EN in the SICU. RH was defined as a post-EN phosphorus (PHOS) level decrement of >0.5 mg/dL to a nadir <2.0 mg/dL within 8 days from EN initiation. We investigated the risk factors for RH and examined its association with clinical outcomes using multivariable regression analyses. RESULTS: In total, 213 patients comprised our analytic cohort. Eighty-three of 213 (39%) individuals experienced RH and 43 of 130 (33%) of the remaining patients experienced non-RH hypophosphatemia (nadir PHOS level <2.0 mg/dL). Overall, there was a total 59% incidence of hypophosphatemia of any cause (N = 126). Nutrition parameters did not differ between groups; most patients were initiated on EN within 48 hours of SICU admission, and timing of EN initiation was not a significant predictor for the development of RH. The median hospital length of stay (LOS) was 21 and 24 days for those with and without RH, respectively (P = .79); RH remained a nonsignificant predictor for hospital LOS in the multivariable analysis. CONCLUSIONS: RH is common in the SICU but is not related to timing or amount of EN. Hypophosphatemia is also common in the critically ill, but regardless of etiology, it was not found to be a predictor of worse clinical outcomes.

Intraoperative Adverse Events in Abdominal Surgery: What Happens in the Operating Room Does Not Stay in the Operating Room.

OBJECTIVE: We sought to assess the impact of intraoperative adverse events (iAEs) on 30-day postoperative mortality, 30-day postoperative morbidity, and postoperative length of stay (LOS) among patients undergoing abdominal surgery. We hypothesized that iAEs would be associated with significant increases in each outcome. SUMMARY OF BACKGROUND DATA: The relationship between iAEs and postoperative clinical outcomes remains largely unknown. METHODS: The 2007 to 2012 institutional ACS-NSQIP and administrative databases for abdominal surgeries were matched then screened for iAEs using the Agency for Healthcare Research and Quality's 15 Patient Safety Indicator, "Accidental Puncture/Laceration". Each chart flagged during the initial screen was then manually reviewed to confirm whether an iAE occurred. Univariate then multivariable logistic regression models were constructed to assess the independent impact of iAEs on 30-day mortality, 30-day morbidity, and prolonged (≥7 days) postoperative LOS, controlling for preoperative/intraoperative variables (eg, age, comorbidities, ASA, wound classification), procedure type (eg, laparoscopic vs open, intestinal, foregut, hepatopancreaticobiliary vs abdominal wall procedure), and complexity (eg, adhesions; relative value units). Propensity score analyses were conducted with each iAE patient matched with 5 non-iAE patients. Sensitivity analyses were performed. RESULTS: A total of 9288 cases were included; 183 had iAEs. Most iAEs consisted of bowel (44%) or vessel (29%) injuries and were addressed intraoperatively (92%). In multivariable analyses, iAEs were independently associated with increased 30-day mortality [OR = 3.19, 95% confidence interval (CI) 1.52-6.71, P = 0.002], 30-day morbidity (OR = 2.68, 95% CI 1.89-3.81, P < 0.001), and prolonged postoperative LOS (OR = 1.85, 95% CI 1.27-2.70, P = 0.001). Postoperative complications associated with iAEs included deep/organ-space surgical site infection (OR = 1.94, 95% CI 1.20-3.14), P = 0.007), sepsis (OR = 2.14, 95% CI 1.32-3.47, P = 0.002), pneumonia (OR = 2.18, 95% CI 1.11-4.26, P = 0.023), and failure to wean ventilator (OR = 3.88, 95% CI 2.17-6.95, P < 0.001). Propensity score matching confirmed these findings, as did multiple sensitivity analyses. CONCLUSIONS: iAEs are independently associated with substantial increases in postoperative mortality, morbidity, and prolonged LOS. Quality improvement efforts should focus on iAE prevention, mitigation of harm after iAEs occur, and risk/severity-adjusted iAE tracking and benchmarking.

Surgery Clerkship Evaluations Are Insufficient for Clinical Skills Appraisal: The Value of a Medical Student Surgical Objective Structured Clinical Examination.

OBJECTIVE: Optimal methods for medical student assessment in surgery remain elusive. Faculty- and housestaff-written evaluations constitute the chief means of student assessment in medical education. However, numerous studies show that this approach has poor specificity and a high degree of subjectivity. We hypothesized that an objective structured clinical examination (OSCE) in the surgery clerkship would provide additional data on student performance that would confirm or augment other measures of assessment. DESIGN: We retrospectively reviewed data from OSCEs, National Board of Medical Examiners shelf examinations, oral presentations, and written evaluations for 51 third-year Harvard Medical School students rotating in surgery at Massachusetts General Hospital from 2014 to 2015. We expressed correlations between numeric variables in Pearson coefficients, stratified differences between rater groups by one-way analysis of variance, and compared percentages with 2-sample t-tests. We examined commentary from both OSCE and clinical written evaluations through textual analysis and summarized these results in percentages. RESULTS: OSCE scores and clinical evaluation scores correlated poorly with each other, as well as with shelf examination scores and oral presentation grades. Textual analysis of clinical evaluation comments revealed a heavy emphasis on motivational factors and praise, whereas OSCE written comments focused on cognitive processes, patient management, and methods to improve performance. CONCLUSIONS: In this single-center study, an OSCE provided clinical skills data that were not captured elsewhere in the surgery clerkship. Textual analysis of faculty evaluations reflected an emphasis on interpersonal skills, rather than appraisal of clinical acumen. These findings suggest complementary roles of faculty evaluations and OSCEs in medical student assessment.

A Pilot Study to Gauge Effectiveness of Standardized Patient Scenarios in Assessing General Surgery Milestones.

PURPOSE: Some General Surgery Milestones can be difficult to assess in traditional clinical settings and especially difficult to assess in junior residents. The purpose of this pilot study was to METHODS: A total of 9 categorical interns participated in a comprehensive, 4-module, SP scenario designed to evaluate and manage right upper quadrant pain. SP checklist scores (SP%) were converted to Milestone-equivalent scores for direct comparison (SP-C). Milestone scores were analyzed from 3 different sources: SP, faculty (FAC), and CCC. Interns completed course evaluations at the end of each session. Spearman's rho was used to determine correlations. Wilcoxon signed rank tests were used to test for differences between scores from different sources. RESULTS: Individual intern Milestone scores from the 3 sources (SP-C, FAC, and CCC) did not correlate. All 7 mean Milestone scores from SPs were significantly higher than from FAC and CCC. FAC and CCC scores were statistically equivalent except for Systems-Based Practice 1 (SBP1) and Patient Care 3 (PC3) where CCC scores were significantly higher than FAC. Mean SP% scores for PC1 were significantly lower than for PROF1, MK1, MK2, and ICS1 (p < 0.05). Interns felt the modules were moderately to very useful. CONCLUSIONS: Developing an SP scenario for Milestones evaluation is feasible. SPs, faculty observers, and CCC each use different data to provide a unique source of Milestone assessment. SP scenarios may be ideally suited to assess specific resident strengths and weaknesses and provide individualized feedback, thus augmenting traditional evaluations. Additional SP scenarios, assessing a broader range of skills and Milestones, are advisable for more reliable estimates of resident performance.

Low baseline (pre-injury) blood pressure predicts inpatient mortality in elderly trauma patients: A bi-institutional study.

OBJECTIVE: The relationship between baseline (i.e., pre-injury) blood pressure and trauma outcomes in elderly patients is unknown. We therefore aimed to identify the independent impact of baseline systolic blood pressure (SBP) on inpatient mortality among elderly trauma patients. METHODS: The 2004 to 2014 trauma registries of two Level I Trauma Centers were linked to electronic health records then reviewed to identify patients ≥65 years old with available baseline vital signs. Baseline SBP was defined as mean outpatient SBP within 2 years before injury. Trauma SBP was defined as first SBP reading after presentation for trauma. Baseline and Trauma SBP were classified as Low (<110 mm Hg), Normal (110-139 mm Hg), or High (≥140 mm Hg). Logistic multivariable regression models were constructed to assess the independent impact of Baseline SBP on inpatient mortality, controlling for demographics, comorbidities, injury mechanism/severity, and Trauma SBP. RESULTS: Of 37,494 patient admissions, 4,233 met inclusion criteria. Median age was 81 years; 63.6% were female. Mortality was 5.39%. In unadjusted analyses, mortality rates were 11.01%, 5.28%, and 4.52% in the Low, Normal, and High Baseline SBP groups, respectively (p = 0.001). In multivariable analyses, patients with Low Baseline SBP had significantly increased mortality risk [OR 3.19 (95% CI 1.62-6.26), p = 0.001] compared to patients with Normal Baseline SBP, in particular when they presented with Low Trauma SBP (<110 mm Hg) [OR 6.14 (2.17-17.36), p = 0.001] or Normal Trauma SBP (110-139 mm Hg) [OR 3.87 (1.43-10.45), p = 0.008]. The mortality risk associated with Low Baseline SBP was particularly elevated among patients with a pre-existing diagnosis of hypertension [OR 4.78 (1.97-11.62), p = 0.001]. CONCLUSION: Low baseline pre-injury SBP is independently associated with more than a threefold increase in inpatient mortality among elderly trauma patients and a fivefold increase in mortality risk among patients with pre-existing hypertension. Given that blood pressure control in the elderly offers a long-term survival advantage, the paradoxical finding of decreased survival after trauma warrants further investigation. LEVEL OF EVIDENCE: Prognostic/epidemiologic study, level III.

Diabetes insipidus uncovered during conservative management of complicated acute appendicitis.

Diabetes insipidus (DI) arises from impaired function of antidiuretic hormone, characterized by hypovolemia, hypernatremia, polyuria, and polydipsia. This case is a reminder of the rare but challenging obstacle that undiagnosed DI poses in fasting surgical patients, requiring prompt recognition and vigilant management of marked homeostatic imbalances.

Virtual Airway Skills Trainer (VAST) Simulator.

This paper presents a simulation of Virtual Airway Skill Trainer (VAST) tasks. The simulated tasks are a part of two main airway management techniques; Endotracheal Intubation (ETI) and Cricothyroidotomy (CCT). ETI is a simple nonsurgical airway management technique, while CCT is the extreme surgical alternative to secure the airway of a patient. We developed identification of Mallampati class, finding the optimal angle for positioning pharyngeal/mouth axes tasks for ETI and identification of anatomical landmarks and incision tasks for CCT. Both ETI and CCT simulators were used to get physicians' feedback at Society for Education in Anesthesiology and Association for Surgical Education spring meetings. In this preliminary validation study, total 38 participants for ETI and 48 for CCT performed each simulation task and completed pre and post questionnaires. In this work, we present the details of the simulation for the tasks and also the analysis of the collected data from the validation study.

Derivation and validation of a novel Emergency Surgery Acuity Score (ESAS).

BACKGROUND: There currently exists no preoperative risk stratification system for emergency surgery (ES). We sought to develop an Emergency Surgery Acuity Score (ESAS) that helps predict perioperative mortality in ES patients. METHODS: Using the 2011 American College of Surgeons' National Surgical Quality Improvement Program (ACS-NSQIP) database (derivation cohort), we identified all surgical procedures that were classified as "emergent." A three-step methodology was then performed. First, multiple logistic regression models were created to identify independent predictors (e.g., patient demographics, comorbidities, and preoperative laboratory variables) of 30-day mortality in ES. Second, based on the relative impact of each identified predictor (i.e., odds ratio), using weighted averages, a novel score was derived. Third, using the 2012 ACS-NSQIP database (validation cohort), the score was validated by calculating its C statistic and evaluating its ability to predict 30-day mortality. RESULTS: From 280,801 NSQIP cases, 18,439 ES cases were analyzed, of which 1,598 (8.7%) resulted in death at 30 days. The multiple logistic regression analyses identified 22 independent predictors of mortality. Based on the relative impact of these predictors, ESAS was derived with a total score range of 0 to 29. ESAS had a C statistic of 0.86; the probability of death at 30 days gradually increased from 0% to 36% then 100% at scores of 0, 11, and 22, respectively. In the validation phase, 19,552 patients were included, the mortality rate was 7.2%, and the ESAS C statistic stayed at 0.86. CONCLUSION: We have therefore developed and validated a novel score, ESAS, that accurately predicts mortality in ES patients. Such a score could prove useful for (1) preoperative patient counseling, (2) identification of patients needing close postoperative monitoring, and (3) risk adjustment in any efforts at benchmarking the quality of ES. LEVEL OF EVIDENCE: Prognostic/epidemiologic study, level III.

Cerium oxide nanoparticles exhibit minimal cardiac and cytotoxicity in the freshwater fish Catostomus commersonii.

Metal oxide nanomaterials can cause oxidative, cardiorespiratory, and osmoregulatory stress in freshwater fish. In contrast, cerium oxide nanoparticles (nCeO2) can have antioxidant effects but their aquatic toxicity has not been fully characterized. Heart rate and heart rate variability were followed in white sucker (Catostomus commersonii) acutely exposed to 1.0 mg L(-1) nCeO2 for 25 h. Malondialdehyde (MDA) was measured to assess oxidative tissue damage, and plasma cortisol, glucose, lactate, and osmolality were assessed as indicators of physiological and osmoregulatory stress. There was no MDA accumulation in gill or heart of fish exposed to nCeO2 and heart function was unchanged over the 25 h treatment. Plasma cortisol increased 6-fold but there was no change in plasma glucose or lactate. Cellular osmoregulatory toxicity was studied using an isolated red blood cell (RBC) model. In vitro exposure to 1.0 mg L(-1) nCeO2 for 1h had no effect on cell morphological parameters and did not sensitize RBCs to hemolysis under hypotonic stress. Overall, there were no indications of oxidative, cardiorespiratory, or osmoregulatory stress following acute exposure to nCeO2. Elevated plasma cortisol levels suggest that nCeO2 may exert mild toxicity to tissues outside of the cardiorespiratory system.

A hierarchical task analysis of cricothyroidotomy procedure for a virtual airway skills trainer simulator.

BACKGROUND: Despite the critical importance of cricothyroidotomy (CCT) for patient in extremis, clinical experience with CCT is infrequent, and current training tools are inadequate. The long-term goal is to develop a virtual airway skills trainer that requires a thorough task analysis to determine the critical procedural steps, learning metrics, and parameters for assessment. METHODS: Hierarchical task analysis is performed to describe major tasks and subtasks for CCT. A rubric for performance scoring for each task was derived, and possible operative errors were identified. RESULTS: Time series analyses for 7 CCT videos were performed with 3 different observers. According to Pearson's correlation tests, 3 of the 7 major tasks had a strong correlation between their task times and performance scores. CONCLUSIONS: The task analysis forms the core of a proposed virtual CCT simulator, and highlights links between performance time and accuracy when teaching individual surgical steps of the procedure.

Nutrition in the Surgical Intensive Care Unit: The Cost of Starting Low and Ramping Up Rates.

BACKGROUND: Calorie/protein deficit in the surgical intensive care unit (SICU) is associated with worse clinical outcomes. It is customary to initiate enteral nutrition (EN) at a low rate and increase to goal (RAMP-UP). Increasing evidence suggests that RAMP-UP may contribute to iatrogenic malnutrition. We sought to determine what proportion of total SICU calorie/protein deficit is attributable to RAMP-UP. MATERIALS AND METHODS: This is a retrospective study of a prospectively collected registry of adult patients (N = 109) receiving at least 72 hours of EN in the SICU according to the RAMP-UP protocol (July 2012-June 2014). Subjects receiving only trophic feeds or with interrupted EN during RAMP-UP were excluded. Deficits were defined as the amount of prescribed calories/protein minus the actual amount received. RAMP-UP deficit was defined as the deficit between EN initiation and arrival at goal rate. Data included demographics, nutritional prescription/delivery, and outcomes. RESULTS: EN was started at a median of 34.0 hours (interquartile range [IQR], 16.5-53.5) after ICU admission, with a mean duration of 8.7 ± 4.3 days. The median total caloric deficit was 2185 kcal (249-4730), with 900 kcal (551-1562) attributable to RAMP-UP (41%). The protein deficit was 98.5 g (27.5-250.4), with 51.9 g (20.6-83.3) caused by RAMP-UP (53%). CONCLUSIONS: In SICU patients initiating EN, the RAMP-UP period accounted for 41% and 53% of the overall caloric and protein deficits, respectively. Starting EN immediately at goal rate may eliminate a significant proportion of macronutrient deficit in the SICU.

The nature, patterns, clinical outcomes, and financial impact of intraoperative adverse events in emergency surgery.

BACKGROUND: Little is known about intraoperative adverse events (iAEs) in emergency surgery (ES). We sought to describe iAEs in ES and to investigate their clinical and financial impact. METHODS: The 2007 to 2012 administrative and American College of Surgeons-National Surgical Quality Improvement Program databases at our tertiary academic center were: (1) linked, (2) queried for all ES procedures, and then (3) screened for iAEs using the ICD-9-CM-based Patient Safety Indicator "accidental puncture/laceration". Flagged cases were systematically reviewed to: (1) confirm or exclude the occurrence of iAEs (defined as inadvertent injuries during the operation) and (2) extract additional variables such as procedure type, approach, complexity (measured by relative value units), need for adhesiolysis, and extent of repair. Univariate and multivariate analyses were performed to assess the independent impact of iAEs on 30-day morbidity, mortality, and hospital charges. RESULTS: Of a total of 9,288 patients, 1,284 (13.8%) patients underwent ES, of which 23 had iAEs (1.8%); 18 of 23 (78.3%) of the iAEs involved the small bowel or spleen, 10 of 23 (43.5%) required suture repair, and 8 of 23 (34.8%) required tissue or organ resection. Compared with those without iAEs, patients with iAEs were older (median age 62 vs 50; P = .04); their procedures were more complex (total relative value unit 46.7, interquartile range [27.5 to 52.6] vs 14.5 [.5 to 30.2]; P < .001), longer in duration (>3 hours: 52% vs 8%; P < .001), and more often required adhesiolysis (39.1% vs 13.5% P = .001). Patients with iAEs had increased total charges ($31,080 vs $11,330, P < .001), direct charges ($20,030 vs $7,387, P < .001), and indirect charges ($11,460 vs $4,088, P < .001). On multivariable analyses, iAEs were independently associated with increased 30-day morbidity (odds ratio, 3.56 [CI, 1.10 to 11.54]; P = .03) and prolonged postoperative length of stay (LOS; LOS >7 days; odds ratio, 5.60 [1.54 to 20.35]; P = .01]. A trend toward increased mortality did not reach statistical significance. CONCLUSIONS: In ES, iAEs are independently associated with significantly higher postoperative morbidity and prolonged LOS.

3D force/torque characterization of emergency cricothyroidotomy procedure using an instrumented scalpel.

Emergency Cricothyroidotomy (CCT) is a surgical procedure performed to secure a patient's airway. This high-stakes, but seldom-performed procedure is an ideal candidate for a virtual reality simulator to enhance physician training. For the first time, this study characterizes the force/torque characteristics of the cricothyroidotomy procedure, to guide development of a virtual reality CCT simulator for use in medical training. We analyze the upper force and torque thresholds experienced at the human-scalpel interface. We then group individual surgical cuts based on style of cut and cut medium and perform a regression analysis to create two models that allow us to predict the style of cut performed and the cut medium.