RESUMO
BACKGROUND: Measuring fluid status during intraoperative hemorrhage is challenging, but detection and quantification of fluid overload is far more difficult. Using a porcine model of hemorrhage and over-resuscitation, it is hypothesized that centrally obtained hemodynamic parameters will predict volume status more accurately than peripherally obtained vital signs. METHODS: Eight anesthetized female pigs were hemorrhaged at 30 ml/min to a blood loss of 400 ml. After each 100 ml of hemorrhage, vital signs (heart rate, systolic blood pressure, mean arterial pressure, diastolic blood pressure, pulse pressure, pulse pressure variation) and centrally obtained hemodynamic parameters (mean pulmonary artery pressure, pulmonary capillary wedge pressure, central venous pressure, cardiac output) were obtained. Blood volume was restored, and the pigs were over-resuscitated with 2,500 ml of crystalloid, collecting parameters after each 500-ml bolus. Hemorrhage and resuscitation phases were analyzed separately to determine differences among parameters over the range of volume. Conformity of parameters during hemorrhage or over-resuscitation was assessed. RESULTS: During the course of hemorrhage, changes from baseline euvolemia were observed in vital signs (systolic blood pressure, diastolic blood pressure, and mean arterial pressure) after 100 ml of blood loss. Central hemodynamic parameters (mean pulmonary artery pressure and pulmonary capillary wedge pressure) were changed after 200 ml of blood loss, and central venous pressure after 300 ml of blood loss. During the course of resuscitative volume overload, changes were observed from baseline euvolemia in mean pulmonary artery pressure and central venous pressure after 500-ml resuscitation, in pulmonary capillary wedge pressure after 1,000-ml resuscitation, and cardiac output after 2,500-ml resuscitation. In contrast to hemorrhage, vital sign parameters did not change during over-resuscitation. The strongest linear correlation was observed with pulmonary capillary wedge pressure in both hemorrhage (r2 = 0.99) and volume overload (r2 = 0.98). CONCLUSIONS: Pulmonary capillary wedge pressure is the most accurate parameter to track both hemorrhage and over-resuscitation, demonstrating the unmet clinical need for a less invasive pulmonary capillary wedge pressure equivalent.
Assuntos
Soluções Cristaloides/administração & dosagem , Hidratação/efeitos adversos , Hemodinâmica , Hemorragia/fisiopatologia , Animais , Volume Sanguíneo , Modelos Animais de Doenças , Feminino , Ressuscitação , Suínos , Sinais VitaisRESUMO
BACKGROUND: Multiple patient factors may convey increased risk of 30-day morbidity and mortality after laparoscopic vertical sleeve gastrectomy (LVSG). Assessing the likelihood of short-term morbidity is useful for both the bariatric surgeon and patient. Artificial neural networks (ANN) are computational algorithms that use pattern recognition to predict outcomes, providing a potentially more accurate and dynamic model relative to traditional multiple regression. Using a comprehensive national database, this study aims to use an ANN to optimize the prediction of the composite endpoint of 30-day readmission, reoperation, reintervention, or mortality, after LVSG. METHODS: A cohort of 101,721 LVSG patients was considered for analysis from the 2016 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program national dataset. Select patient factors were chosen a priori as simple, pertinent and easily obtainable, and their association with the 30-day endpoint was assessed. Those factors with a significant association on both bivariate and multivariate nominal logistic regression analysis were incorporated into a back-propagation ANN with three nodes each assigned a training value of 0.333, with k-fold internal validation. Logistic regression and ANN models were compared using area under receiver-operating characteristic curves (AUROC). RESULTS: Upon bivariate analysis, factors associated with 30-day complications were older age (P = 0.03), non-white race, higher initial body mass index, severe hypertension, diabetes mellitus, non-independent functional status, and previous foregut/bariatric surgery (all P < 0.001). These factors remained significant upon nominal logistic regression analysis (n = 100,791, P < 0.001, r2= 0.008, AUROC = 0.572). Upon ANN analysis, the training set (80% of patients) was more accurate than logistic regression (n = 80,633, r2= 0.011, AUROC = 0.581), and it was confirmed by the validation set (n = 20,158, r2= 0.012, AUROC = 0.585). CONCLUSIONS: This study identifies a panel of simple and easily obtainable preoperative patient factors that may portend increased morbidity after LSG. Using an ANN model, prediction of these events can be optimized relative to standard logistic regression modeling.
Assuntos
Gastrectomia , Laparoscopia , Redes Neurais de Computação , Obesidade , Adulto , Estudos de Coortes , Biologia Computacional , Bases de Dados Factuais , Feminino , Gastrectomia/efeitos adversos , Gastrectomia/mortalidade , Gastrectomia/estatística & dados numéricos , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/mortalidade , Laparoscopia/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Morbidade , Obesidade/epidemiologia , Obesidade/mortalidade , Obesidade/cirurgia , Readmissão do Paciente/estatística & dados numéricos , Reoperação/estatística & dados numéricosRESUMO
BACKGROUND: Laparoscopic Roux-en-Y gastric bypass (LRYGB) is a common, safe and effective bariatric procedure. Bleeding is a significant source of postoperative morbidity. We aimed to determine the incidence, outcomes, and predictors of postoperative bleeding after LRYGB. METHODS: LRYGB patients included in the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) 2015 dataset were identified. Preoperative and intraoperative factors were tested for associations with bleeding using univariable and multivariable logistic regression analysis. Outcomes of length of stay, in-hospital mortality, 30-day mortality, discharge disposition, and 30-day complications among patients with and without clinically significant postoperative bleeding were compared using multivariable regression. RESULTS: In the 43,280 LRYGB patients included in this analysis, postoperative bleeding occurred in 652 (1.51%) patients. Of these, 165 (25.3%) underwent a re-operation and 97 (14.9%) underwent an unplanned endoscopy for 'bleeding'. Postoperative bleeding was associated with a longer median postoperative length of stay (4 vs. 2 days), higher in-hospital mortality (1.23 vs. 0.04%), higher 30-day mortality (1.38 vs. 0.15%), discharge to an extended-care facility (3.88 vs. 0.6%), and higher rates of major complications (all P < 0.05). Independent predictors of postoperative bleeding included; a history of renal insufficiency (OR 2.55, 95% CI 1.43-4.52), preoperative therapeutic anticoagulation (OR 2.44, 95% CI 1.69-3.53), and revisional surgery (OR 1.45, 95% CI 1.06-1.97). Intraoperative associated factors included conversions (OR 3.37, 95% CI 1.42-7.97), and drain placement (OR 1.40, 95% CI 1.18-1.67). Robotic approaches resulted in independently lower postoperative bleeding rates (OR 0.50, 95% CI 0.32-0.77). CONCLUSIONS: Postoperative bleeding occurs in 1.5% of patients undergoing a LRYGB and is associated with significantly increased morbidity and mortality. We have identified patient and operative factors that are independently associated with postoperative bleeding.
Assuntos
Derivação Gástrica/métodos , Laparoscopia , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias , Hemorragia Pós-Operatória , Adulto , Idoso , Feminino , Mortalidade Hospitalar , Humanos , Incidência , Laparoscopia/métodos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/mortalidade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Hemorragia Pós-Operatória/epidemiologia , Hemorragia Pós-Operatória/etiologia , Melhoria de QualidadeRESUMO
Inferior mesenteric artery (IMA) aneurysms are a rare entity, attributing to 1% of Splanchnic aneurysms (Edogawa S, Shibuya T, Kurose K et al. Inferior mesenteric artery aneurysm: case report and literature review. Ann Vasc Dis 2013;6:98-101), often found incidentally on evaluation for other intra-abdominal pathologies. Similar to other visceral arterial aneurysms, there is an estimated 20-50% risk of potentially fatal rupture and repair is generally recommended. We report 2 patients with IMA aneurysms, using them as cases to illustrate feasibility of both open and endovascular management options. Patient 1 is a 69-year-old male with bilateral claudication found to have an asymptomatic 20-mm IMA aneurysm. This patient underwent aortobifemoral bypass with branch polytetrafluoroethylene graft to distal IMA after excision of IMA aneurysm. Patient 2 is a 32-year-old male who underwent an ex vivo renal artery aneurysm repair and was noted on routine follow-up to have an incidental saccular 1.5-cm IMA aneurysm for which he underwent endovascular coil embolization. Both patients had an unremarkable postoperative course with a notable absence of stigmata of bowel ischemia.
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Aneurisma/terapia , Implante de Prótese Vascular , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Artéria Mesentérica Inferior/cirurgia , Adulto , Idoso , Aneurisma/diagnóstico por imagem , Aneurisma/cirurgia , Prótese Vascular , Implante de Prótese Vascular/instrumentação , Angiografia por Tomografia Computadorizada , Humanos , Masculino , Artéria Mesentérica Inferior/diagnóstico por imagem , Politetrafluoretileno/química , Desenho de Prótese , Resultado do TratamentoRESUMO
OBJECTIVE: Inspired by the limited facility of the Penn classification, the authors aimed to determine a rapid and optimal preoperative assessment tool to predict surgical mortality after acute Stanford type-A aortic dissection (AAAD) repair. DESIGN: Patients who underwent an attempted surgical repair of AAAD were determined using a de-identified single institution database. The charts of 144 patients were reviewed retrospectively for preoperative demographics and surrogates for disease severity and malperfusion. Bivariate analysis was used to determine significant (p≤0.05) predictors of in-hospital and 1-year mortality, the primary endpoints. Receiver operating characteristic curve generation was used to define optimal cut-off values for continuous predictors. SETTING: Single center, level 1 trauma, university teaching hospital. PARTICIPANTS: The study included 144 cardiac surgical patients with acute type-A aortic dissection presenting for surgical correction. INTERVENTIONS: Surgical repair of aortic dissection with preoperative laboratory samples drawn before patient transfer to the operating room or immediately after arterial catheter placement intraoperatively. MEASUREMENTS AND MAIN RESULTS: The study cohort comprised 144 patients. In-hospital mortality was 9%, and the 1-year mortality rate was 17%. Variables that demonstrated a correlation with in-hospital mortality included an elevated serum lactic acid level (odds ratio [OR] 1.5 [1.3-1.9], p<0.001), a depressed ejection fraction (OR 0.91 [0.86-0.96], p = .001), effusion (OR 4.8 [1.02-22.5], p = 0.04), neurologic change (OR 5.3 [1.6-17.4], p = 0.006), severe aortic regurgitation (OR 8.2 [2.0-33.9], p = 0.006), and cardiopulmonary resuscitation (OR 6.8 [1.7-26.9], p = 0.01). Only an increased serum lactic acid level demonstrated a trend with 1-year mortality using univariate Cox regression (hazard ratio 1.1 [1.0-1.1], p = 0.006). Receiver operating characteristic analysis revealed optimal cut-off lactic acid levels of 6.0 mmol/L and 6.9 mmol/L for in-hospital and 1-year mortality, respectively. CONCLUSION: Lactic acidosis, ostensibly as a surrogate for systemic malperfusion, represents a novel, accurate, and easily obtainable preoperative predictor of short-term mortality after attempted AAAD repair. These data may improve identification of patients who would not benefit from surgery.
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Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Hiperlactatemia/diagnóstico , Doença Aguda , Idoso , Dissecção Aórtica/mortalidade , Aneurisma Aórtico/mortalidade , Biomarcadores/sangue , Feminino , Mortalidade Hospitalar , Humanos , Hiperlactatemia/complicações , Ácido Láctico/sangue , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Valor Preditivo dos Testes , Cuidados Pré-Operatórios/métodos , Prognóstico , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Procedimentos Cirúrgicos Vasculares/mortalidadeRESUMO
OBJECTIVES: Unregulated intraoperative distension of human saphenous vein (SV) graft leads to supraphysiologic luminal pressures and causes acute physiologic and cellular injury to the conduit. The effect of distension on tissue viscoelasticity, a biophysical property critical to a successful graft, is not well described. In this investigation, we quantify the loss of viscoelasticity in SV deformed by distension and compare the results to tissue distended in a pressure-controlled fashion. MATERIALS AND METHODS: Unmanipulated porcine SV was used as a control or distended without regulation and distended with an in-line pressure release valve (PRV). Rings were cut from these tissues and suspended on a muscle bath. Force versus time tracings of tissue constricted with KCl (110 mM) and relaxed with sodium nitroprusside (SNP) were fit to the Hill model of viscoelasticity, using mean absolute error (MAE) and r2-goodness of fit as measures of conformity. RESULTS: One-way ANOVA analysis demonstrated that, in tissue distended manually, the MAE was significantly greater and the r2-goodness of fit was significantly lower than both undistended tissues and tissues distended with a PRV (p<0.05) in KCl-induced vasoconstriction and SNP-induced vasodilation. CONCLUSIONS: Unregulated manual distension of SV graft causes loss of viscoelasticity and such loss may be mitigated with the use of an in-line PRV.
Assuntos
Ponte de Artéria Coronária/métodos , Endotélio Vascular/fisiopatologia , Veia Safena/cirurgia , Animais , Humanos , Suínos , VasoconstriçãoRESUMO
Traditional methods of intraoperative human saphenous vein preparation for use as bypass grafts can be deleterious to the conduit. The purpose of this study was to characterize acute graft preparation injury, and to mitigate this harm via an improved preparation technique. Porcine saphenous veins were surgically harvested (unprepared controls, UnP) and prepared using traditional (TraP) and improved preparations (ImP). The TraP used unregulated radial distension, marking with a surgical skin marker and preservation in heparinized normal saline. ImP used pressure-regulated distension, brilliant blue FCF-based pen marking and preservation in heparinized Plasma-Lyte A. Rings from each preparation were suspended in a muscle bath for characterization of physiologic responses to vasoactive agents and viscoelasticity. Cellular viability was assessed using the methyl thiazolyl tetrazolium (MTT) assay and the terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay for apoptosis. Contractile responses to potassium chloride (110 mM) and phenylephrine (10 µM), and endothelial-dependent and independent vasodilatory responses to carbachol (0.5 µM) and sodium nitroprusside (1 µM), respectively, were decreased in TraP tissues compared to both UnP and ImP tissues (p ⩽ 0.05). TraP tissues demonstrated diminished viscoelasticity relative to UnP and ImP tissues (p ⩽ 0.05), and reduced cellular viability relative to UnP control (p ⩽ 0.01) by the MTT assay. On the TUNEL assay, TraP tissues demonstrated a greater degree of apoptosis relative to UnP and ImP tissues (p ⩽ 0.01). In conclusion, an improved preparation technique prevents vascular graft smooth muscle and endothelial injury observed in tissues prepared using a traditional approach.
Assuntos
Preservação de Órgãos/métodos , Veia Safena/transplante , Coleta de Tecidos e Órgãos/métodos , Vasoconstrição , Vasodilatação , Animais , Anticoagulantes/farmacologia , Apoptose , Sobrevivência Celular , Elasticidade , Eletrólitos/farmacologia , Heparina/farmacologia , Modelos Animais , Preservação de Órgãos/efeitos adversos , Soluções para Preservação de Órgãos/farmacologia , Veia Safena/efeitos dos fármacos , Veia Safena/patologia , Veia Safena/fisiopatologia , Cloreto de Sódio/farmacologia , Sus scrofa , Fatores de Tempo , Coleta de Tecidos e Órgãos/efeitos adversos , Rigidez Vascular , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , ViscosidadeRESUMO
INTRODUCTION: Laparoscopic Roux-en-Y gastric bypass (LRYGB) has become the gold standard for surgical weight loss. The success of LRYGB may be measured by excess body mass index loss (%EBMIL) over 25 kg/m(2), which is partially determined by multiple patient factors. In this study, artificial neural network (ANN) modeling was used to derive a reasonable estimate of expected postoperative weight loss using only known preoperative patient variables. Additionally, ANN modeling allowed for the discriminant prediction of achievement of benchmark 50% EBMIL at 1 year postoperatively. METHODS: Six hundred and forty-seven LRYGB included patients were retrospectively reviewed for preoperative factors independently associated with EBMIL at 180 and 365 days postoperatively (EBMIL180 and EBMIL365, respectively). Previously validated factors were selectively analyzed, including age; race; gender; preoperative BMI (BMI0); hemoglobin; and diagnoses of hypertension (HTN), diabetes mellitus (DM), and depression or anxiety disorder. Variables significant upon multivariate analysis (P < .05) were modeled by "traditional" multiple linear regression and an ANN, to predict %EBMIL180 and %EBMIL365. RESULTS: The mean EBMIL180 and EBMIL365 were 56.4 ± 16.5 % and 73.5 ± 21.5%, corresponding to total body weight losses of 25.7 ± 5.9% and 33.6 ± 8.0%, respectively. Upon multivariate analysis, independent factors associated with EBMIL180 included black race (B = -6.3%, P < .001), BMI0 (B = -1.1%/unit BMI, P < .001), and DM (B = -3.2%, P < .004). For EBMIL365, independently associated factors were female gender (B = 6.4%, P < .001), black race (B = -6.7%, P < .001), BMI0 (B = -1.2%/unit BMI, P < .001), HTN (B = -3.7%, P = .03), and DM (B = -6.0%, P < .001). Pearson r(2) values for the multiple linear regression and ANN models were 0.38 (EBMIL180) and 0.35 (EBMIL365), and 0.42 (EBMIL180) and 0.38 (EBMIL365), respectively. ANN prediction of benchmark 50% EBMIL at 365 days generated an area under the curve of 0.78 ± 0.03 in the training set (n = 518) and 0.83 ± 0.04 (n = 129) in the validation set. CONCLUSIONS: Available at https://redcap.vanderbilt.edu/surveys/?s=3HCR43AKXR, this or other ANN models may be used to provide an optimized estimate of postoperative EBMIL following LRYGB.
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Derivação Gástrica , Laparoscopia , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Redução de Peso , Adulto , Índice de Massa Corporal , Feminino , Derivação Gástrica/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Redes Neurais de Computação , Obesidade Mórbida/fisiopatologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Resultado do TratamentoRESUMO
INTRODUCTION: Laparoscopic adjustable gastric banding (LAGB) represents a safe and effective bariatric procedure, particularly for patients over 50. Preoperative risk factors for impaired post-LAGB excess weight loss are not well characterized for this population. This study aimed to identify demographics, characteristics or comorbidities associated with excess weight loss at 6 and 12 months postoperatively (EWL180 and EWL365, respectively) for these patients. METHODS: One hundred and seventeen LAGB patients >50 years of age from 2005 to 2014 were retrospectively reviewed for factors potentially associated with EWL180 and EWL365. Rationally selected variables chosen for analysis included age, race, gender, initial body mass index and preoperative weight loss; comorbidities assessed included hypertension, psychiatric disorders and diabetes mellitus (DM). Variables correlated with EWL180 or EWL365 on bivariate linear regression analysis (P ≤ .05) were input into multivariate linear regression analysis to confirm independent association. RESULTS: Preoperative DM (B = -9.1% EWL; 95% CI -13.6, -4.5%; P < .001) and African-American race (B = -8.8% EWL; 95% CI -17.3, -0.3%; P = .05) were independent risk factors for impaired EWL180. Only DM was a risk factor for impaired EWL365 (B = -9.7% EWL; 95% CI -17.7, -1.8%; P = .02). CONCLUSIONS: LAGB is a successful operation in patients >50 years of age. Preoperative DM is an independent risk factor for impaired EWL in this cohort.
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Diabetes Mellitus Tipo 2/complicações , Gastroplastia/métodos , Laparoscopia , Obesidade Mórbida/cirurgia , Redução de Peso , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade Mórbida/complicações , Estudos Retrospectivos , Fatores de Risco , Resultado do TratamentoRESUMO
INTRODUCTION: Bariatric surgery is the most effective method for producing sustained weight loss, improving obesity-associated comorbidities and reducing inflammation in the morbidly obese population. The red cell distribution width (RDW) is a novel marker of inflammation that is usually reported as part of a complete blood count. In this study, we tested our hypothesis that red cell distribution width might represent a novel biomarker predictive of excess body-mass index loss (EBMIL) following laparoscopic Roux-en-Y gastric bypass (LRYGB). METHODS: Five hundred and forty-seven LRYGB patients included from a single institution were individually reviewed, noting both preoperative RDW and percent excess BMI loss at 6 months and 1 year post-LRYGB (%EBMIL180 and %EBMIL365, respectively). Bivariate and multivariate linear regression analysis was conducted between age, gender, initial body-mass index (BMI0) and RDW and each of the two endpoints, to assess the independence of RDW as a predictor of postoperative success. RESULTS: The median RDW was 13.9 (13.3-14.6) %, and median EBMIL180 and EBMIL365 were 55.4 (45.2-66.7) % and 71.3 (58.9-87.8) %, respectively. After controlling for age, gender and BMI0, RDW was associated with %EBMIL365 (B = -1.4 [-2.8 to -0.002] %, P = .05), but not %EBMIL180 (B = -0.6 [-1.6 to 0.5] %, P = .30. Upon Kruskal-Wallis analysis, patients with a preoperative RDW > 15.0 % had significantly lower %EBMIL than those in the <13.0 % (P < .001) and 13.0-15.0 % (P < .01) strata. CONCLUSIONS: RDW is predictive of EBMIL at 1 year following LRYGB. This represents a novel preoperative biomarker that may provide clinically useful prognostic information.
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Índices de Eritrócitos , Derivação Gástrica/métodos , Obesidade Mórbida/cirurgia , Adulto , Cirurgia Bariátrica , Biomarcadores/sangue , Feminino , Humanos , Laparoscopia/métodos , Análise dos Mínimos Quadrados , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade Mórbida/sangue , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Redução de PesoRESUMO
BACKGROUND: The above-knee amputation (AKA) is an operation of last resort with high postoperative morbidity and mortality. This study identifies preoperative risk factors predictive of both 30-day mortality and extended length of stay (LOS) in AKA patients. METHODS: Two hundred ninety-five AKA patients from 2004 to 2013 from a single institution were retrospectively reviewed using a deidentified electronic medical record. Rationally selected factors potentially influencing 30-day mortality and LOS were chosen, including demographics, etiologies, vascular surgical history, lifestyle factors, comorbidities, and laboratory values. Variables trending with one of the end points on bivariate analysis (P ≤ 0.10) were entered into multivariate forward stepwise regression models to determine independence as a risk factor (P ≤ 0.05). Subgroup analysis of AKA patients without a traumatic, burn, or malignant etiology was similarly conducted. RESULTS: Within the 295 patient cohort, 60% of the patients were male, 18% were African American, mean age was 58 years and mean body mass index was 28 kg/m(2). The 30-day mortality rate was 9%, and mean postoperative LOS of discharged patients was 9.3 days. Upon logistic regression, thrombocytopenia (platelet count < 250 × 10(6)/mL, P < 0.001, odds ratio 6.1) and preoperative septic shock (P = 0.02, odds ratio 5.1) were identified as independent risk factors for 30-day mortality. Upon linear regression, burn etiology (P < 0.001, B = 15.8 days), leukocytosis (white blood cell count > 12 × 10(6)/mL, P < 0.001, B = 6.2 days), and guillotine amputation (P < 0.001, B = 7.6 days) were independently associated with prolonged LOS. Excluding patients with AKAs due to trauma, burn, or malignancy, only thrombocytopenia (platelet count < 250 × 10(6)/mL, P < 0.001, odds ratio 10.2) and leukocytosis (white blood cell count > 12 × 10(6)/mL, P = 0.01, B = 5.2 days) were independent risk factors for in-hospital mortality and prolonged LOS, respectively. CONCLUSIONS: Preoperative septic shock and thrombocytopenia are independent risk factors for 30-day mortality after AKA, while burn etiology, leukocytosis, and guillotine amputation contribute to prolonged LOS. Awareness of these risk factors may help enhance both preoperative decision making and expectations of the hospital admission.
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Amputação Cirúrgica/efeitos adversos , Amputação Cirúrgica/mortalidade , Mortalidade Hospitalar , Tempo de Internação , Doença Arterial Periférica/cirurgia , Adulto , Idoso , Distribuição de Qui-Quadrado , Registros Eletrônicos de Saúde , Feminino , Humanos , Modelos Lineares , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/mortalidade , Doença Arterial Periférica/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Tennessee , Fatores de Tempo , Resultado do TratamentoRESUMO
OBJECTIVE: Ruptured abdominal aortic aneurysm (rAAA) carries a high mortality rate, even with prompt transfer to a medical center. An artificial neural network (ANN) is a computational model that improves predictive ability through pattern recognition while continually adapting to new input data. The goal of this study was to effectively use ANN modeling to provide vascular surgeons a discriminant adjunct to assess the likelihood of in-hospital mortality on a pending rAAA admission using easily obtainable patient information from the field. METHODS: Of 332 total patients from a single institution from 1998 to 2013 who had attempted rAAA repair, 125 were reviewed for preoperative factors associated with in-hospital mortality; 108 patients received an open operation, and 17 patients received endovascular repair. Five variables were found significant on multivariate analysis (P < .05), and four of these five (preoperative shock, loss of consciousness, cardiac arrest, and age) were modeled by multiple logistic regression and an ANN. These predictive models were compared against the Glasgow Aneurysm Score. All models were assessed by generation of receiver operating characteristic curves and actual vs predicted outcomes plots, with area under the curve and Pearson r(2) value as the primary measures of discriminant ability. RESULTS: Of the 125 patients, 53 (42%) did not survive to discharge. Five preoperative factors were significant (P < .05) independent predictors of in-hospital mortality in multivariate analysis: advanced age, renal disease, loss of consciousness, cardiac arrest, and shock, although renal disease was excluded from the models. The sequential accumulation of zero to four of these risk factors progressively increased overall mortality rate, from 11% to 16% to 44% to 76% to 89% (age ≥ 70 years considered a risk factor). Algorithms derived from multiple logistic regression, ANN, and Glasgow Aneurysm Score models generated area under the curve values of 0.85 ± 0.04, 0.88 ± 0.04 (training set), and 0.77 ± 0.06 and Pearson r(2) values of .36, .52 and .17, respectively. The ANN model represented the most discriminant of the three. CONCLUSIONS: An ANN-based predictive model may represent a simple, useful, and highly discriminant adjunct to the vascular surgeon in accurately identifying those patients who may carry a high mortality risk from attempted repair of rAAA, using only easily definable preoperative variables. Although still requiring external validation, our model is available for demonstration at https://redcap.vanderbilt.edu/surveys/?s=NN97NM7DTK.
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Aneurisma da Aorta Abdominal/mortalidade , Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/mortalidade , Ruptura Aórtica/cirurgia , Implante de Prótese Vascular/mortalidade , Técnicas de Apoio para a Decisão , Procedimentos Endovasculares/mortalidade , Mortalidade Hospitalar , Redes Neurais de Computação , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Aneurisma da Aorta Abdominal/diagnóstico , Ruptura Aórtica/diagnóstico , Área Sob a Curva , Implante de Prótese Vascular/efeitos adversos , Bases de Dados Factuais , Procedimentos Endovasculares/efeitos adversos , Feminino , Parada Cardíaca/mortalidade , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Choque/mortalidade , Tennessee , Fatores de Tempo , Resultado do Tratamento , Inconsciência/mortalidadeRESUMO
OBJECTIVE: Prompt carotid endarterectomy (CEA) in clinically significant carotid stenosis is important in the prevention of neurologic sequelae. The greatest benefit from surgery is obtained by prompt revascularization on diagnosis. It has been demonstrated that black patients both receive CEA less frequently than white patients do and experience worse postoperative outcomes. We sought to test our hypothesis that black race is an independent risk factor for a prolonged time from sonographic diagnosis of carotid stenosis warranting surgery to the day of operation (TDO). METHODS: From 1998 to 2013 at a single institution, 166 CEA patients were retrospectively reviewed using Synthetic Derivative, a de-identified electronic medical record. Factors potentially affecting TDO, including demographics, preoperative cardiac stress testing, degree of stenosis, smoking status, and comorbidities, were noted. Multivariate analysis was performed on variables that trended with prolonged TDO on univariate analysis (P < .10) to determine independent (P < .05) predictors of TDO. Subgroup analyses were further performed on the symptomatic and asymptomatic stenosis cohorts. RESULTS: There were 32 black patients and 134 white patients studied; the mean TDO was 78 ± 17 days vs 33 ± 3 days, respectively (P < .001). In addition to the need for preoperative cardiac stress testing, black race was the only variable that demonstrated a trend with (P < .10) or was an independent risk factor for (P < .05) prolonged TDO among all patients (B = 42 days; P < .001) and within the symptomatic (B = 35 days; P = .08) and asymptomatic (B = 35 days; P = .003) cohorts. On Kaplan-Meier analysis, black patients in each stratum of symptomatology (all, symptomatic, and asymptomatic patients) experienced prolonged TDO (log-rank, P < .03 for all three groups). CONCLUSIONS: Black race is a risk factor for a temporal delay in CEA for carotid stenosis. Awareness of this disparity may help surgeons avoid undesirable delays in operation for their black patients.
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Negro ou Afro-Americano , Estenose das Carótidas/etnologia , Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas , Disparidades em Assistência à Saúde/etnologia , Tempo para o Tratamento , Idoso , Estenose das Carótidas/diagnóstico por imagem , Registros Eletrônicos de Saúde , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Lineares , Masculino , Análise Multivariada , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Tennessee/epidemiologia , Fatores de Tempo , Ultrassonografia , População BrancaRESUMO
BACKGROUND: Conversion of sleeve gastrectomy to Roux-en-Y gastric bypass is indicated primarily for unsatisfactory weight loss or gastroesophageal reflux disease (GERD). This study aimed to use a comprehensive database to define predictors of 30-day reoperation, readmission, reintervention, or mortality. An artificial neural network (ANN) was employed to optimize prediction of the composite endpoint (occurrence of 1+ morbid event). METHODS: Areview of 8895 patients who underwent conversion for weight-related or GERD-related indications was performed using the 2021 MBSAQIP national dataset. Demographics, comorbidities, laboratory values, and other factors were assessed for bivariate and subsequent multivariable associations with the composite endpoint (P ≤ .05). Factors considered in the multivariable model were imputed into a three-node ANN with 20% randomly withheld for internal validation, to optimize predictive accuracy. Models were compared using receiver operating characteristic (ROC) curve analysis. RESULTS: 39% underwent conversion for weight considerations and 61% for GERD. Rates of 30-day reoperation, readmission, reintervention, mortality, and the composite endpoint were 3.0%, 7.1%, 2.1%, .1%, and 9.1%, respectively. Of the nine factors associated with the composite endpoint on bivariate analysis, only non-white race (P < .001; odds ratio 1.4), lower body-mass index (P < .001; odds ratio .22), and therapeutic anticoagulation (P = .001; odds ratio 2.0) remained significant upon multivariable analysis. Areas under ROC curves for the multivariable regression, ANN training, and validation sets were .587, .601, and .604, respectively. DISCUSSION: Identification of risk factors for morbidity after conversion offers critical information to improve patient selection and manage postoperative expectations. ANN models, with appropriate clinical integration, may optimize prediction of morbidity.
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Gastrectomia , Derivação Gástrica , Refluxo Gastroesofágico , Redes Neurais de Computação , Obesidade Mórbida , Complicações Pós-Operatórias , Reoperação , Humanos , Derivação Gástrica/métodos , Derivação Gástrica/mortalidade , Feminino , Masculino , Gastrectomia/mortalidade , Gastrectomia/métodos , Pessoa de Meia-Idade , Adulto , Reoperação/estatística & dados numéricos , Obesidade Mórbida/cirurgia , Refluxo Gastroesofágico/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/mortalidade , Readmissão do Paciente/estatística & dados numéricos , Estudos RetrospectivosRESUMO
Background: The vertical banded gastroplasty (VBG) is a historic restrictive bariatric operation often requiring further surgery. In this investigation utilizing the 2021 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) national dataset, we aim to better define the outcomes of VBG conversions.Methods: We queried the 2021 MBSAQIP dataset for patients who underwent a conversion from a VBG to Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG). Demographics, comorbidities, laboratory values, and additional patient factors were examined. Rates of key consequential outcome measures 30-day readmission, reoperation, reintervention, mortality, and a composite endpoint (at least 1 of the 4) were further calculated.Results: We identified 231 patients who underwent conversion from VBG to SG (n = 23), RYGB (n = 208), or other anatomy (n = 6), of which 93% of patients were female, and 22% of non-white race. The median age was 56 years and body-mass index (BMI) was 43 kg/m2. The most common surgical indications included weight considerations (48%), reflux (25%), anatomic causes (eg, stricture, fistula, and ulcer; 10%), and dysphagia (6.5%). Thirty-day morbidity rates included reoperation (7.8%), readmission (9.1%), reintervention (4.3%), mortality (.4%), and the composite endpoint (15%). Upon bivariate analysis, we did not identify any specific risk factor for the 30-day composite endpoint.Discussion: One-stage VBG conversions to traditional bariatric anatomy are beset with higher 30-day morbidity relative to primary procedures. Additional MBSAQIP data will be required for aggregation, to better characterize the risk factors inherent in these operations.
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Background Animal models of distributive hypotension and resuscitation allow the assessment of hemodynamic monitoring modalities and resuscitation strategies. The fluid-first paradigm for resuscitation is currently being challenged with clinical trials. In this investigation, venous return and perfusion are assessed, and full hemodynamics are characterized, in a porcine model of endotoxemic hypotension with and without fluid pre-loading. Methods Two groups of six pigs had the induction of standardized endotoxemic hypotension ("critical hypotension"). Group 1 underwent four 10 cc/kg crystalloid boluses, and Group 2 was not fluid pre-resuscitated. Both groups underwent progressive norepinephrine (NE) up-titration to 0.25 mcg/kg/minute over 30 minutes. Vital signs, central parameters, and laboratory values were obtained at baseline, "critical hypotension," after each bolus and during NE administration. Results Endotoxemia decreased the systemic vascular resistance (SVR) in Group 1 (1031±106 dyn/s/cm-5 versus 738±258 dyn/s/cm-5; P=0.03) and Group 2 (1121±196 dyn/s/cm-5 versus 759±342 dyn/s/cm-5; P=0.003). In Group 1, the four fluid boluses decreased heart rate (HR), pulmonary capillary wedge pressure (PCWP), and central venous pressure (CVP) (P<0.05). No changes were observed in blood pressure, cardiac output (CO), or lactate. NE up-titration increased HR in Group 1 and decreased CVP in both groups. Higher final CVP (11 {3} versus 4 {4} mmHg; P=0.01) and PCWP (5 {1} versus 2 {2} mmHg; P=0.005) values were observed in Group 1 relative to Group 2, reflecting increased venous return. Conclusions Porcine endotoxemic hypotension and resuscitation were robustly characterized. In this model, fluid loading improved venous return with NE, though perfusion (CO) was preserved by increased NE-induced chronotropy.
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BACKGROUND: Cardiac output (CO) is a valuable proxy for perfusion, and governs volume responsiveness during resuscitation from distributive shock. The underappreciated venous system has nuanced physiology that confers valuable hemodynamic information. In this investigation, deconvolution of the central venous waveform by the fast Fourier transformation (FFT) algorithm is performed to assess its ability to constitute a CO surrogate in a porcine model of endotoxemia-induced distributive hypotension and resuscitation. STUDY DESIGN: Ten pigs were anesthetized, catheterized, and intubated. A lipopolysaccharides infusion protocol was used to precipitate low systemic vascular resistance hypotension. Four crystalloid boluses (10 cc/kg) were then given in succession, after which heart rate, mean arterial pressure, thermodilution-derived CO, central venous pressure (CVP), and the central venous waveform were collected, the last undergoing fast Fourier transformation analysis. The amplitude of the fundamental frequency of the central venous waveform's cardiac wave (f0-CVP) was obtained. Heart rate, mean arterial pressure, CVP, f0-CVP, and CO were plotted over the course of the boluses to determine whether f0-CVP tracked with CO better than the vital signs, or than CVP itself. RESULTS: Distributive hypotension to a 25% mean arterial pressure decrement was achieved, with decreased systemic vascular resistance (mean 918 ± 227 [SD] dyne/s/cm-5 vs 685 ± 180 dyne/s/cm-5; p = 0.038). Full hemodynamic parameters characterizing this model were reported. Slopes of linear regression lines of heart rate, mean arterial pressure, CVP, f0-CVP, and CO were -2.8, 1.7, 1.8, 0.40, and 0.35, respectively, demonstrating that f0-CVP values closely track with CO over the 4-bolus range. CONCLUSIONS: Fast Fourier transformation analysis of the central venous waveform may allow real-time assessment of CO during resuscitation from distributive hypotension, possibly offering a venous-based approach to clinical estimation of volume responsiveness.
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Endotoxemia , Hipotensão , Suínos , Animais , Débito Cardíaco/fisiologia , Hemodinâmica , Hipotensão/etiologia , Hipotensão/terapia , Ressuscitação/métodosRESUMO
BACKGROUND: Preoperative anemia has been suggested as a contraindication to gastric bypass. Using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement database, this study sought to determine the role of preoperative hematocrit on 30-day morbidity and mortality after laparoscopic Roux-en-Y gastric bypass for weight loss. METHODS: A cohort of 31 981 patients was reviewed for factors associated with a composite primary end point including 30-day reoperation, readmission, reintervention, or mortality, including degree of anemia. Analyzed separately by gender, factors significant on bivariate analysis were included in nominal logistic multivariate analysis to assess for independent significance of the hematocrit level as a risk factor for the primary end point. RESULTS: Upon multivariate analysis, the hematocrit level was significantly associated with the 30-day end point in the male cohort (P = .05), specifically, severe anemia (hematocrit <35%) conferred an increased risk relative to a normal hematocrit (odds ratio 1.5, P = .03). There was no association of hematocrit with the 30-day end point in the female cohort. CONCLUSION: Bariatricians should carefully consider the appropriateness of a gastric bypass over a less anemogenic procedure such as sleeve gastrectomy in patients, particularly men with preoperative anemia.
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Anemia/complicações , Derivação Gástrica/efeitos adversos , Derivação Gástrica/mortalidade , Adulto , Anemia/sangue , Contraindicações de Procedimentos , Feminino , Hematócrito , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/cirurgia , Readmissão do Paciente , Período Pré-Operatório , ReoperaçãoRESUMO
The objective of this study was to assess the results of a structured remediation program for surgical residents scoring poorly on the American Board of Surgery In-Training Examination®. Residents scoring below the threshold (<20th percentile) were placed in a remediation program consisting of textbook-based review and mandatory weekly quizzes overseen by the program director. The effects of the program were assessed over a five-year period (2014-2018). Of 168 tests taken, 23 (13.7%) instances of scoring below the threshold occurred (average percentile 11, range 1-19). Postremediation scores in the subsequent year improved with a median (IQR) percentile increase of 29 [23.5, 46] (P < 0.001). Two residents scored below the threshold twice; all others continued to score above the threshold. Participation in a structured remediation program results in dramatic improvement in American Board of Surgery In-Training Examination® performance, and a single occurrence of poor performance does not necessarily lead to a permanent handicap in academic performance.
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Competência Clínica , Educação de Pós-Graduação em Medicina/organização & administração , Cirurgia Geral/educação , Internato e Residência/organização & administração , Ensino de Recuperação/organização & administração , Adulto , Currículo , Bases de Dados Factuais , Avaliação Educacional , Feminino , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos , Inquéritos e Questionários , Estados UnidosRESUMO
Measures to reduce postoperative bleeding (POB) after bariatric surgery is skewed toward laparoscopic sleeve gastrectomy (LSG). We use 2015 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) to characterize the differences in bleeding rates between LSG and laparoscopic Roux-en-Y gastric bypasses (LRYGB). Propensity score matching and multivariable logistic regressions tested for independent differences in POB rates. A total of 168,093 patients from 742 centers were identified in the data set. After selection 36,925 patients with LRYGB and 20,020 patients with LSG were included in the analysis. A total of 710 (1.25%) patient suffered a POB. The independent odds of POB were 38% lower for patients having LSG compared with those having LRYGB (odds ratio, 0.62; 95% confidence interval=0.51-0.76). This difference is more pronounced with intraoperative securing of the staple line. Appropriate measures to reduce POB after each type of bariatric procedure is warranted.