Machine learning based DNA melt curve profiling enables automated novel genotype detection.

Surveillance for genetic variation of microbial pathogens, both within and among species, plays an important role in informing research, diagnostic, prevention, and treatment activities for disease control. However, large-scale systematic screening for novel genotypes remains challenging in part due to technological limitations. Towards addressing this challenge, we present an advancement in universal microbial high resolution melting (HRM) analysis that is capable of accomplishing both known genotype identification and novel genotype detection. Specifically, this novel surveillance functionality is achieved through time-series modeling of sequence-defined HRM curves, which is uniquely enabled by the large-scale melt curve datasets generated using our high-throughput digital HRM platform. Taking the detection of bacterial genotypes as a model application, we demonstrate that our algorithms accomplish an overall classification accuracy over 99.7% and perform novelty detection with a sensitivity of 0.96, specificity of 0.96 and Youden index of 0.92. Since HRM-based DNA profiling is an inexpensive and rapid technique, our results add support for the feasibility of its use in surveillance applications.

Lower Extremity Arterial Reconstruction in Octogenarians and Older.

BACKGROUND: Despite previous single-institution studies showing that lower extremity arterial reconstruction (LEAR) in octogenarians and older patients may be undertaken with acceptable postoperative morbidity and mortality, there continues to be significant reluctance, in the vascular surgical community, to undertaking these complex revascularization procedures in this very elderly population. We undertook this study in an effort to determine the outcomes of LEAR in octogenarians and older patients on a national level. METHODS: The American College of Surgeons' National Surgical Quality Improvement Program database was queried to identify all patients who underwent LEAR between January 1, 2005 and December 31, 2009. Patient demographics and presenting comorbidities were recorded, and multivariate analyses were performed to compare outcomes in patients 80 and older to those in younger patients. RESULTS: There were 19,028 patients who underwent open infrainguinal LEAR during this time period. Patients ≥80 comprised 18% (3,486 patients), and patients <80 years comprised 82% (15,542 patients). Multivariate analysis demonstrated that patients aged ≥80 years had an increased likelihood of mortality (odds ratio [OR] 1.79; 95% confidence interval [CI] 1.42-2.26), cardiovascular (OR, 1.46; 95% CI, 1.12-1.89), respiratory (OR, 1.37; 95% CI, 1.12-1.67), and renal (OR, 1.57; 95% CI, 1.27-1.95) complications. There was, however, no significant difference in the likelihood of graft failure (OR, 1.04; 95% CI, 0.86-1.27), wound infection (OR, 0.92; 95% CI, 0.79-1.06), or major amputation (OR, 0.59; 95% CI, 0.13-2.74) between these 2 groups. CONCLUSIONS: LEAR in octogenarians is associated with an increased risk of postoperative morbidity and mortality but no increased risk of wound infection, amputation, or graft failure.

Incremental Cost of Emergency Versus Elective Surgery.

OBJECTIVE: To determine hospital costs and the adjusted risk of death associated with emergent versus elective surgery. BACKGROUND: Emergency surgery has a higher cost and worse outcomes compared with elective surgery. However, no national estimates of the excess burden of emergency surgery exist. METHODS: Nationwide Inpatient Sample (NIS) data from 2001 to 2010 were analyzed. Patients aged 18 years or older who underwent abdominal aortic aneurysm repair, coronary artery bypass graft, or colon resection for neoplasm were included. Using generalized linear models with propensity scores, cost differences for emergent versus elective admission were calculated for each procedure. Multivariable logistic regression was performed to investigate the adjusted odds of mortality comparing elective and emergent cases. Discharge-level weights were applied to analyses. RESULTS: A total of 621,925 patients, representing a weighted population of 3,057,443, were included. The adjusted mean cost difference for emergent versus elective care was $8741.22 (30% increase) for abdominal aortic aneurysm repair, $5309.78 (17% increase) for coronary artery bypass graft, and $7813.53 (53% increase) for colon resection. If 10% of the weighted estimates of emergency procedures had been performed electively, the cost benefit would have been nearly $1 billion, at $996,169,160 (95% confidence interval [CI], $985,505,565-$1,006,834,104). Elective surgery patients had significantly lower adjusted odds of mortality for all procedures. CONCLUSIONS: Even a modest reduction in the proportion of emergent procedures for 3 conditions is estimated to save nearly $1 billion over 10 years. Preventing emergency surgery through improved care coordination and screening offers a tremendous opportunity to save lives and decrease costs.

Estimating the influence of maternal height on under-five mortality in Nigeria.

This study uses a nationally representative data sample to assess the effect of maternal height as an intergenerational influence on under-five mortality. Data from the 2003 and 2008 Nigerian Demographic Health Survey (NDHS) (n = 41,005) selecting women aged 15 to 49 yrs whose most recent births were within 5 years (n = 23,568), were analyzed. The outcome measure was under-five mortality. Independent variables included maternal height categorized as > or = 63 inch, 61-62.9 inch, 59.1-60.9 inch, < 59.1 inch. Confounding factors were controlled for. A multivariable logistic regression was used to obtain odds ratio estimates along with their respective confidence interval. After adjusting for confounding factors, we found that each 1 inch increase in maternal height, was associated with a decreased odds of mortality OR 0.98 (95% CI 0.97-0.99). The OR of under-five mortality when comparing women > or = 63 inch versus women < 59.1 inch was 1.13 (95% CI 0.98-1.31). The population attributable fraction of child death due to maternal short stature was 0.36.

Characterizing lobular carcinoma of the male breast using the SEER database.

BACKGROUND: Lobular carcinoma of the male breast is rare. We sought to investigate the clinical characteristics, treatment, and outcomes of men and women with lobular breast cancer, using a population-based database. METHODS: We reviewed the Surveillance, Epidemiology, and End Results database 1988-2008 and identified patients with a lobular breast cancer diagnosis (invasive lobular carcinoma [ILC] and lobular carcinoma in situ [LCIS]) using the "International Classification of Diseases for Oncology, Third Edition" codes. Bivariate analyses compared the male and female patients on demographics, clinical characteristics, and treatment modalities. Multivariate logistic regression analysis determined the risk-adjusted likelihood of receiving treatment. Survival analysis was done and hazard ratios were obtained using Cox proportional models. RESULTS: Overall, 133,339 patients were identified, including 133,168 women (99.9%) and 171 men (0.1%). Most had ILC (82.08%). The median age was 66 ± 20 y for the men and 61 ± 21 y for the women. The men with ILC were more likely to have poorly differentiated tumors (26.45% versus 15.61%; P < 0.001) and stage IV disease (9.03% versus 4.18%; P = 0.005) than were the women. The cancer-specific 5-year survival rates for ILC were 82.9% for the men and 91.9% for the women. Adjusted survival was better for patients with ILC receiving surgery plus radiotherapy than patients receiving neither (hazard ratio 0.52, 95% confidence interval 0.49-0.56). Women with ILC had a 55% increased odds of receiving surgery plus radiotherapy compared with men (odds ratio 1.55, 95% confidence interval 1.08-2.22). CONCLUSIONS: ILC presents at a higher grade and stage in men. The difference in disease characteristics and survival rates suggests that the treatment of men with lobular breast cancer should be adjusted to improve their outcomes.

Surgical management of esophageal diverticulum: a review of the Nationwide Inpatient Sample database.

BACKGROUND: Esophageal diverticulum is rare in the United States. The mainstay treatment of symptomatic esophageal diverticulum is surgical correction. Much of the available information regarding esophageal diverticulum and its surgical management has been derived from small studies and institutional reviews. Our study objective was to investigate the demographics, perioperative conditions, and predictors of outcomes after surgical treatment of acquired esophageal diverticulum using a nationally representative database. METHODS: A retrospective review using the Nationwide Inpatient Sample database from 2000-2009 was performed for patients with acquired esophageal diverticulum. The patients were stratified into Zenker's diverticulum (ZD) or non-Zenker's diverticulum (NZD) subgroups. The covariates retrieved included age, gender, ethnicity, insurance type, and Charlson comorbidity index. A multivariate analysis was performed to determine the predictors of postoperative morbidity. Discharge-level weights were applied. RESULTS: Overall, a total of 4253 patients met our inclusion criteria, 3197 (75%) with ZD and 1056 (25%) with NZD. In the ZD group, the mean age was 73 ± 12.3 y, and most were men (55%) and white (67%). The mean length of stay was 5.82 ± 8.08 d, and the mortality rate was 1.2%. The most common complication was septicemia or sepsis (2.0%). The black patients had higher odds of postoperative morbidity than the white patients (odds ratio [OR] 2.29, 95% confidence interval [CI] 1.02-5.17). The risk of overall postoperative morbidity was 52% greater for women (OR 1.52, 95% CI 1.01-2.29). An increasing Charlson comorbidity index was an independent predictor of morbidity. In the NZD group, the mean age was 69 ± 13.9 y, and most were also men (51%) and white (63%). The mean length of stay was 8.13 ± 10.56 d, and the mortality rate was 1.6%. The most common complication was air leak (3.1%). The black and Hispanic patients had higher odds of postoperative morbidity than the white patients (OR 1.97, 95% CI 1.05-3.72 and OR 2.37, 95% CI 1.06-5.30, respectively). An increasing Charlson comorbidity index was an independent predictor of morbidity. Compared with laparoscopy, the risk of developing postoperative morbidity was higher with the thoracotomy procedure (OR 7.45, 95% CI 1.11-50.18). CONCLUSIONS: Using a nationally representative database, our study found that female gender, black race, and the presence of comorbidities were associated with increased postoperative morbidity among patients with ZD. Among the patients with NZD, black and Hispanic patients had worse postoperative morbidity than the white patients, and the presence of comorbidities was associated with increased postoperative morbidity. Thoracotomy for the correction of NZD was associated with increased postoperative morbidity compared with the laparoscopic approach.

Diabetes mellitus is not associated with major morbidity following open abdominal aortic aneurysm repair.

BACKGROUND: It has been suggested that there is an increased morbidity and mortality risk for diabetics undergoing elective aortic surgery. This, however, is not universally accepted. In this study, we utilize a national database to determine if diabetes is associated with adverse outcomes following open, elective, infrarenal abdominal aortic aneurysm (AAA) repair. METHODS: The American College of Surgeons' National Surgical Quality Improvement Program database was queried to identify all patients who underwent an open, elective, nonruptured AAA repair from January 1, 2005 to December 31, 2007. Patient demographics, comorbidities, and outcomes were compared by diabetes status. Multivariate analysis was performed adjusting for demographics and comorbidities. RESULTS: There were 2110 American College of Surgeons' National Surgical Quality Improvement Program patients who underwent an open, elective, nonruptured AAA repair during this time period. Of these patients, 245 (11.6%) had diabetes mellitus. The overall mortality rate was 3.7% (5.3% for diabetics and 3.5% for nondiabetics, P = 0.171). On bivariate analysis, diabetics were more likely to present preoperatively with cardiovascular and renal comorbidities. Postoperatively, there was no significant difference in mortality or in cardiac, pulmonary, or renal complications. Diabetics were more likely to develop superficial surgical site infections (SSIs) (4.5% versus 1.6%, P = 0.002). On multivariate regression, there was no difference in mortality or major complications between diabetics and nondiabetics (OR 1.4, 95% CI 0.68-2.71). Diabetics, however, were almost three times more likely to develop superficial SSIs (OR 2.8, 95% CI 1.29-6.00). CONCLUSIONS: Diabetes mellitus is not associated with significantly worse major outcomes following open, elective, infrarenal AAA repair. Diabetics, however, are more likely to develop superficial SSIs.

Open reduction internal fixation versus hemiarthroplasty versus total hip arthroplasty in the elderly: a review of the National Surgical Quality Improvement Program database.

BACKGROUND: Total hip arthroplasty (THA), hemiarthroplasty (HA), and open reduction internal fixation (ORIF) are treatment options for femoral neck fractures. However, the optimal surgical treatment remains unclear. The present study aimed to describe the 30-d postoperative outcomes of THA, HA, and ORIF among patients aged ≥65 y with femoral neck fractures within a national surgical database. MATERIALS AND METHODS: A retrospective analysis of the American College of Surgeons National Surgical Quality Improvement Program for January 2005 through December 2009 was conducted. We included patients aged ≥65 y who had undergone THA, HA, or ORIF for femoral neck fractures. We collected information on patient demographics, comorbidities, risk factors, and complication rates. A logistic regression model was used to assess the variation in overall morbidity and mortality after surgery. RESULTS: Overall, 3423 patients met the inclusion criteria: 674 underwent ORIF, 428 HA, and 2321 THA. Most patients were white (83.6%, n = 2862), female (64.4%, n = 2204), and >70 y old (78.4%, n = 2682). On adjusted multivariate analysis, no differences were found in the 30-d mortality rates among the ORIF, HA, and THA groups. Patients who underwent ORIF (odds ratio 0.51, 95% confidence interval 0.27-0.94) and HA (odds ratio 0.43, 95% confidence interval 0.22-0.84) had a lower likelihood of developing respiratory complications compared with those who underwent THA. CONCLUSIONS: No differences were found in the 30-d mortality rates among the ORIF, HA, and THA groups. ORIF and HA resulted in a lower likelihood of developing respiratory complications than THA.

National cost of trauma care by payer status.

BACKGROUND: Several studies have described the burden of trauma care, but few have explored the economic burden of trauma inpatient costs from a payer's perspective or highlighted the differences in the average costs per person by payer status. The present study provides a conservative inpatient national trauma cost estimate and describes the variation in average inpatient trauma cost by payer status. METHODS: A retrospective analysis of patients who had received trauma care at hospitals in the Nationwide Inpatient Sample from 2005-2010 was conducted. Our sample patients were selected using the appropriate "International Classification of Diseases, Ninth Revision, Clinical Modification" codes to identify admissions due to traumatic injury. The data were weighted to provide national population estimates, and all cost and charges were converted to 2010 US dollar equivalents. Generalized linear models were used to describe the costs by payer status, adjusting for patient characteristics, such as age, gender, and race, and hospital characteristics, such as location, teaching status, and patient case mix. RESULTS: A total of 2,542,551 patients were eligible for the present study, with the payer status as follows: 672,960 patients (26.47%) with private insurance, 1,244,817 (48.96%) with Medicare, 262,256 (10.31%) with Medicaid, 195,056 (7.67%) with self-pay, 18,506 (0.73%) with no charge, and 150,956 (5.94%) with other types of insurance. The estimated yearly trauma inpatient cost burden was highest for Medicare at $17,551,393,082 (46.79%), followed by private insurance ($10,772,025,421 [28.72%]), Medicaid ($3,711,686,012 [9.89%], self-pay ($2,831,438,460 [7.55%]), and other payer types ($2,370,187,494 [6.32%]. The estimated yearly trauma inpatient cost burden was $274,598,190 (0.73%) for patients who were not charged for their inpatient trauma treatment. Our adjusted national inpatient trauma yearly costs were estimated at $37,511,328,659 US dollars. Privately insured patients had a significantly higher mean cost per person than did the Medicare, Medicaid, self-pay, or no charge patients. CONCLUSIONS: The results of the present study have demonstrated that the distribution of trauma burden across payers is significantly different from that of the overall healthcare system and suggest that although the burden of trauma is high, the burden of self-pay or nonreimbursed inpatient services is actually lower than that of overall medical care.

Plasma Biomarker for Post-concussive Syndrome: A Pilot Study Using an Alternating Current Electro-Kinetic Platform.

Background: Technology platforms that afford biomarker discovery in patients suffering from traumatic brain injury (TBI) remain an unmet medical need. Here, we describe an observational pilot study to explore the utility of an alternating current electrokinetic (ACE) microchip device in this context. Methods: Blood samples were collected from participating subjects with and without minor TBI. Plasma levels of glial fibrillary acidic protein (GFAP), Tau, ubiquitin C-terminal hydrolase L1 (UCH-L1), and cell-free DNA (cfDNA) were determined in subjects with and without minor TBI using ACE microchip device followed by on-chip immunofluorescent analysis. Post-concussive symptoms were assessed using the Rivermead Post Concussion Symptoms Questionnaire (RPCSQ) at one-month follow-up. Results: Highest levels of GFAP, UCH-L1, and Tau were seen in two minor TBI subjects with abnormality on head computed tomography (CT). In patients without abnormal head CT, Tau and GFAP levels discriminated between plasma from minor-TBI and non-TBI patients, with sensitivity and specificity of 64-72 and 50%, respectively. Plasma GFAP, UCH-L1, and Tau strongly correlated with the cumulative RPCSQ score. Plasma UCH-L1 and GFAP exhibited highest correlation to sensitivity to noise and light (r = 0.96 and 0.91, respectively, p < 0.001). Plasma UCH-L1 and Tau showed highest correlation with headache (r = 0.74 and 0.78, respectively, p < 0.001), sleep disturbance (r = 0.69 and 0.84, respectively, p < 0.001), and cognitive symptoms, including forgetfulness (r = 0.76 and 0.74, respectively, p < 0.001), poor concentration (r = 0.68 and 0.76, respectively, p < 0.001), and time required for information processing (r = 0.77 and 0.81, respectively, p < 0.001). cfDNA exhibited a strong correlation with depression (r = 0.79, p < 0.01) and dizziness (r = 0.69, p < 0.01). While cfDNA demonstrated positive correlation with dizziness and depression (r = 0.69 and 0.79, respectively, p < 0.001), no significant correlation was observed between cumulative RPCSQ and cfDNA (r = 0.07, p = 0.81). Conclusion: We provide proof-of-principle results supporting the utility of ACE microchip for plasma biomarker analysis in patients with minor TBI.

An Age-Based Analysis of Pediatric Melanoma: Staging, Surgery, and Mortality in the Surveillance, Epidemiology, and End Results Database.

The pediatric melanoma population is not well described, and current guidelines for their management are not well defined. Our study aims to identify this population, treatment modalities, and outcomes using a national population-based database. We reviewed the Surveillance, Epidemiology, and End Results database (2004-2008). Patients ≤21 years old with melanoma were included and grouped into ≤12 years of age, 13 to 18 years, and 19 to 21 years. Clinical characteristics were analyzed across the groups. A total of 1255 patients were included: 52.7 per cent were 19 to 21 years of age, 36.3 per cent were 13 to 18 years of age, and 11.0 per cent were ≤12 years of age. The 19- to 21-year-olds had the highest proportion of stage I (50.5%) versus ≤12 years of age (31.9%); the ≤12-year-olds had the highest proportion of stage IV (3.6%) versus 19 to 21 years of age (0.9%), P < 0.001. The 19- to 21-year-olds had the highest proportion receiving wide local excisions only (34.8%) versus ≤12 years of age (26.4%); the ≤12-year-olds had the highest proportion of patients without any surgeries (16.0%) versus 13 to 18 years of age (9.4%), P = 0.169. On adjusted analysis, the 19- to 21-year-olds had worse survival compared with ≤12 years of age (hazard ratio: 5.26, P = 0.017, 95% confidence interval 1.34-20.65). Disparities were found in the ≤12-year-old melanoma population, as they had later stage melanomas, less invasive surgery, and lower survival. Clearer prognostic factors are needed to better elucidate their management.

Trauma associated splenic artery aneurysms: an analysis of the National Trauma Data Bank.

BACKGROUND: Trauma associated splenic artery aneurysm (SAA) is potentially life threatening and infrequently studied. We evaluated the subject using a large trauma database. METHODS: The National Trauma Data Bank (2002 to 2006) was queried. All patients aged greater than or equal to 18 years with a primary diagnosis of SAA (International Classification of Diseases: Ninth Revision code 442.83) were identified. Data on demographics, injury severity, pre-existing comorbidities, surgical interventions, complications, and mortality were analyzed. RESULTS: One hundred twenty-four patients were included with a mean age of 40 ± 13 years and 72% were male. Mean Injury Severity Score was 24 ± 12. All patients suffered blunt trauma, and 5% of the patients (n = 6) had systolic blood pressure less than 90 mm Hg on arrival. The most frequent interventions were surgical ligation of aneurysm (45%), bronchoscopy (35%), endovascular procedures (27%), splenectomy (27%), and thoracostomy tube (25%). About 1.7% developed pulmonary collapse. Mean length of stay was 13 days and mortality was 1.6%. CONCLUSIONS: Trauma associated SAA has low mortality and most patients require surgical intervention. Pulmonary dysfunction and invasive pulmonary procedures are frequent despite low rate of chest injuries possibly due to anatomic proximity of lung and spleen.

The impact of coagulopathy on traumatic splenic injuries.

BACKGROUND: Patients with pre-injury coagulopathy have worse outcomes than those without coagulopathy. This article investigated the risk-adjusted effect of pre-injury coagulopathy on outcomes after splenic injuries. METHODS: Review of the National Trauma Data Bank from 2007 to 2010 comparing mortality and complications between splenic injury patients with and without a pre-injury bleeding disorder. RESULTS: Of 58,896 patients, 2% had a bleeding disorder. Coagulopathic patients had higher odds of mortality (odds ratio, 1.3), sepsis (odds ratio, 2.0), acute respiratory distress syndrome (odds ratio, 2.6), acute renal failure (odds ratio, 1.5), cardiac arrest (odds ratio, 1.5), and overall complications (odds ratio, 2.4). The higher odds of myocardial infarction did not achieve statistical significance (odds ratio, 1.6). CONCLUSIONS: Pre-injury coagulopathy in patients with splenic injury has a negative impact on cardiac arrest, sepsis, acute respiratory distress syndrome, acute renal failure, and mortality. The higher likelihood of myocardial infarction did not reach statistical significance.

Assessment of racial and sex disparities in open femoral fractures.

BACKGROUND: Open femoral fractures are common; however, many factors may affect treatment protocol. We aim to assess any racial/ethnic or sex disparities associated with the definitive fixation of open femoral fractures. METHODS: ICD-9 codes from the National Trauma Data Bank (2007 to 2010) for patients greater than or equal to 18 years with open femoral fractures who underwent operative management at level I or II trauma centers were identified and analyzed. RESULTS: Of the 9,406 cases, the majority were White (61%), men (73%), and aged between 25 and 44 years (41%). The odds of definitive fixation after hospital day 2 (odds ratio [OR] .96, 95% confidence interval [CI] .82 to 1.09, P = .53) or any complication (OR .96, 95% CI .79 to 1.15, P = .69) were not associated with race/ethnicity. Men were 17% less likely to have surgery after hospital day 2 (OR .83, 95% CI .78 to .96, P < .001), and 18% more likely to have a complication (OR 1.18, 95% CI 1.03 to 1.35, P = .02). CONCLUSIONS: There are no racial/ethnic disparities associated with the timing of definitive fixation. Men are more likely to undergo fixation earlier than women; however, they are more likely to have a complication. Fixation within the first 2 hospital days may decrease complications.

African-American Men with Low-Risk Prostate Cancer: Modern Treatment and Outcome Trends.

OBJECTIVE: To investigate the clinical characteristics and treatment patterns for African-American (AA) men with low-risk prostate cancer (PCa) using a national, population-based dataset. METHODS: We conducted a retrospective review of the Surveillance Epidemiology and End Results database 2004-2008. AA men aged ≥40 years with low-risk PCa were identified. For comparison, white men were selected using the same selection criteria. We reviewed all recorded treatment modalities. Definitive treatment (DT) was defined as undergoing radiotherapy or prostatectomy. RESULTS: Overall, 7246 AA men and 47,154 white men met the criteria. Most of the patients had PSA level between 4.1 and 6.9 ng/mL (56.2 %) and received DT (76 %). Black men were younger (mean age: 62(±8) vs. 65(±10) years), less likely to receive DT (adjusted odds ratio (AOR), 0.71 [0.67-0.76]), and of those receiving DT, less likely to undergo prostatectomy (AOR, 0.58 [0.54-0.62]). Patients receiving DT had lower crude cancer-specific and overall mortality (0.17 vs. 0.41 % and 2.9 vs. 7.8 %, p value < 0.001, respectively, among blacks). The difference in overall mortality was largest among ≥ 75 years (5.6 vs. 18.2 %). Across age groups, blacks had higher all-cause mortality (AOR, 1.45 [1.13-1.87] and 1.56[1.31-1.86] for <65 and ≥ 65 years, respectively). CONCLUSION: Our study of a large modern cohort of men with low-risk PCa demonstrates significant lower receipt of DT, lower receipt of prostatectomy among those receiving DT, and lower survival for black men compared to their white counterparts. Older men were less likely to receive DT. Patients who received DT had better survival. The survival difference was most striking among the elderly.

Open abdominal surgery: a risk factor for future laparoscopic surgery?

BACKGROUND: This study seeks to investigate the outcomes of laparoscopic procedures in patients with previous open abdominal surgery. METHODS: Using data from the National Surgical Quality Improvement Program (2005 to 2009), we identified patients who had undergone laparoscopic cholecystectomy, Nissen fundoplication, Heller myotomy, splenectomy, Roux-en-Y, sleeve gastrectomy, gastric band, appendectomy, or colectomy. Patients were then classified as to whether adhesiolysis (AD) was also carried out. Bivariate and multivariate analysis was used to compare groups. RESULTS: A total of 162,415 patients met our inclusion criteria, comprising 4,501 (3%) in the AD group and 157,913 (97%) in the nonadhesiolysis (NAD) group. Patient who had received lysis of adhesion were older, had 41% higher odds of overall complications, 17% higher adjusted mean lysis of adhesion (P < .001), and 26% higher adjusted mean operation duration (P < .001). CONCLUSIONS: A history of previous open abdominal surgery increases the potential complication rate and hospital length of stay during subsequent laparoscopic surgery. The extent of this relationship deserves further investigation.

Optimal time for early laparoscopic cholecystectomy for acute cholecystitis.

IMPORTANCE: There is growing evidence in support of performing early laparoscopic cholecystectomy (LC) for acute cholecystitis. However, the definition of early LC varies from 0 through 10 days depending on the research protocol. The optimum time to perform early LC is still unclear. OBJECTIVES: To determine whether outcomes after early LC for acute cholecystitis vary depending on time from presentation to surgery and to determine the optimum time to perform LC for acute cholecystitis. DESIGN, SETTING, AND PARTICIPANTS: We performed a retrospective review of prospectively collected data from the Nationwide Inpatient Sample (NIS) for 2005 through 2009. The population-based sample included 95,523 adults (18 years and older) who underwent LC within 10 days of presentation for acute cholecystitis. INTERVENTIONS: Patients were categorized and analyzed in 2 ways based on length of time from presentation to surgery. First, patients were categorized into 3 groups: 0 through 1 day, 2 through 5 days, and 6 through 10 days. Second, we compared outcomes for each incremental preoperative day (days 0-5). MAIN OUTCOMES AND MEASURES: Outcomes of interest were mortality, length of stay, complications, and cost. Propensity score matching and generalized linear modeling were used. The hypothesis being tested was formulated after data collection was complete. RESULTS: A total of 95,523 patients were selected. After matching the 3 groups based on propensity scores, patients who underwent surgery during days 2 through 5 and days 6 through 10 had increasingly worse outcomes when compared with those undergoing surgery on days 0 through 1. The odds of mortality were 1.26 (95% CI, 1.00-1.58) and 1.93 (95% CI, 1.38-2.68), and the odds of postoperative infections were 0.88 (95% CI, 0.69-1.12) and 1.53 (95% CI, 1.05-2.23) for days 2 through 5 and days 6 through 10, respectively. Adjusted mean hospital cost increased from $8974 (days 0-1) to $17,745 (days 6-10). Analysis by each incremental day revealed the optimal time of surgery to be within the first 48 hours of presentation. CONCLUSIONS AND RELEVANCE: Laparoscopic cholecystectomy performed within 2 days of presentation of acute cholecystitis yielded the best outcomes and lowest costs. Although causality could not be established, delaying LC was associated with more complications, higher mortality, and higher costs.

Lower extremity arterial reconstruction in obese patients.

BACKGROUND: Previous reports have noted that obese patients undergoing lower extremity arterial reconstruction have higher complication rates compared with nonobese patients. We evaluated the effect of obesity on outcomes following open infrainguinal arterial reconstruction on a national level. METHODS: A query of the American College of Surgeons' National Surgical Quality Improvement Program Database was conducted to identify all adult patients who underwent open infrainguinal lower extremity arterial reconstruction from 2005 to 2009. Postoperative outcomes were analyzed in different body mass index groups. RESULTS: Obese and morbidly obese patients had a higher risk of wound infection when compared with normal weight patients (odds ratios 2.1 and 2.7, P < .05). Obese patients had a lower mortality when compared with normal weight patients (odds ratio .83, P < .05). CONCLUSIONS: Obesity was associated with an increase in wound infection after open lower extremity arterial reconstruction. Obesity, but not morbid obesity, was associated with decreased mortality.

Body mass index in blunt trauma patients with hemorrhagic shock: opposite ends of the body mass index spectrum portend poor outcome.

BACKGROUND: There are controversial data on the relationship between trauma and body mass index. We investigated this relationship in traumatic hemorrhagic shock. METHODS: The "Glue Grant" database was analyzed, stratifying patients into underweight, normal weight (NW), overweight, Class I obesity, Class II obesity, and Class III obesity. Predictors of mortality and surgical interventions were statistically determined. RESULTS: One thousand nine hundred seventy-six patients were included with no difference in injury severity between groups. Marshall's score was elevated in overweight (5.3 ± 2.7, P = .016), Class I obesity (5.8 ± 2.7, P < .001), Class II obesity (5.9 ± 2.8, P < .001), and Class III obesity (6.3 ± 3.0, P < .001) compared with NW (4.8 ± 2.6). Underweight had higher lactate (4.8 ± 4.2 vs 3.3 ± 2.5, P = .04), were 4 times more likely to die (odds ratio 3.87, confidence interval 2.22 to 6.72), and were more likely to undergo a laparotomy (odds ratio 2.06, confidence interval 1.31 to 3.26) than NW. CONCLUSION: Early assessment of body mass index, with active management of complications in each class, may reduce mortality in traumatic hemorrhagic shock.

Outcomes of trauma care at centers treating a higher proportion of older patients: the case for geriatric trauma centers.

BACKGROUND: The burden of injury among older patients continues to grow and accounts for a disproportionate number of trauma deaths. We wished to determine if older trauma patients have better outcomes at centers that manage a higher proportion of older trauma patients. METHODS: The National Trauma Data Bank years 2007 to 2011 was used. All high-volume Level 1 and Level 2 trauma centers were included. Trauma centers were categorized by the proportion of older patients seen. Adult trauma patients were categorized as older (≥65 years) and younger adults (16-64 years). Coarsened exact matching was used to determine differences in mortality and length of stay between older and younger adults. Risk-adjusted mortality ratios by proportion of older trauma patients seen were analyzed using multivariate logistic regression models and observed-expected ratios. RESULTS: A total of 1.9 million patients from 295 centers were included. Older patients accounted for one fourth of trauma visits. Matched analysis revealed that older trauma patients were 4.2 times (95% confidence interval, 3.99-4.50) more likely to die than younger patients. Older patients were 34% less likely to die if they presented at centers treating a high versus low proportion of older trauma (odds ratio, 0.66; 95% confidence interval, 0.54-0.81). These differences were independent of trauma center performance. CONCLUSION: Geriatric trauma patients treated at centers that manage a higher proportion of older patients have improved outcomes. This evidence supports the potential advantage of treating older trauma patients at centers specializing in geriatric trauma. LEVEL OF EVIDENCE: Prognostic and epidemiologic study, level III.