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INTRODUCTION: Prolonged Casualty Care (PCC) is a military adaptation aimed at providing pre-hospital care in austere settings when evacuation is delayed or even impossible. Current lack of standardized medical equipment and size/weight restrictions of military packs during dismounted operations hinder effective PCC. We sought to design a standardized, practical, and effective prolonged field care kit (PFAK) to enable widespread implementation of PCC. MATERIALS AND METHODS: We reviewed Joint Trauma System Clinical Practice Guidelines to generate a list of potential contents of the PFAK. We obtained Institutional Review Board (IRB) exemption and then conducted stakeholder surveys of combat casualty care experts across the Joint Trauma System using a modified Delphi survey approach. We established a civil-military working group that provided in-depth qualitative feedback on the PFAK contents and provided an initial design of a long-range medical rucksack (LMR) to house it. Responses were analyzed using mean rank scores to help determine initial components of the PFAK. Tactical subject-matter experts tested and evaluated the PFAK and LMR prototype in austere conditions to refine the design. RESULTS: Review of the PCC Clinical Practice Guidelines generated 49 medications and 301 potential supplies as potential PFAK contents. The first Delphi survey was sent to 100 stakeholders (overall response rate of 60%). After the first survey, contents were narrowed to a list of the most essential 27 medications and 105 other components. Iterative prototypes of the PFAK and LMR were tested to determine ergonomics, portability, flexibility, and equipment compartmentalization to facilitate use in emergencies. The prototype was optimized to address the clinical, logistical, and tactical requirements of PCC across a variety of platforms and environmental conditions. CONCLUSIONS: Given the changing battlefield environment, efficient and effective PCC will play an increasingly important role in the management of combat trauma. The PFAK can meet this need by providing a practical and standardized resuscitation kit generated by expert military and trauma personnel consensus, carried conveniently in the LMR.
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Técnica Delphi , Humanos , Encuestas y Cuestionarios , Servicios Médicos de Urgencia/métodos , Servicios Médicos de Urgencia/tendencias , Servicios Médicos de Urgencia/normas , Medicina Militar/métodos , Medicina Militar/tendencias , Medicina Militar/instrumentación , Medicina Militar/normas , Heridas y Lesiones/terapia , Personal Militar/estadística & datos numéricosRESUMEN
OBJECTIVE: Leadership is an essential skill for surgeons, but it is not systematically taught in residency. The objective of this study was to explore the current experiences, motivators, and perspectives on leadership training of general surgery residents. DESIGN/SETTING/PARTICIPANTS: Semi-structured focus groups were conducted with 20 general surgery residents at an academic training program. Six in-person sessions (one for each postgraduate year and research) were recorded, transcribed, and de-identified. Data were inductively coded by 2 independent researchers and analyzed thematically. Discrepancies were discussed and resolved through consensus. RESULTS: Participants described developing their leadership skills prior to residency through formal (e.g., job and military) and informal (e.g., extracurricular) experiences. Most reported that leadership development during residency occurred informally (e.g., emulating mentors, trial-and-error). Evolving responsibilities and expectations shaped residents' leadership values: junior residents focused on student and task management and adaptation to new teams; mid-level residents emphasized emotional intelligence and delivery of resident feedback; and senior residents stressed team engagement, inspiring the team, and teaching/mentoring. Major transition periods between residency levels were identified as critical times for leadership training as they allow for self-reflection, motivating residents to participate in a leadership curriculum. Employing level appropriate and immediately applicable content during this time would encourage curriculum attendance and prepare residents for new roles. CONCLUSIONS: There is a lack of formal leadership training in general surgery residency. There is an opportunity to design and implement leadership training that engages surgical residents with level-relevant content and strategies. Transition periods offer optimal timing for maximal curricula uptake.
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Grupos Focales , Cirugía General , Internado y Residencia , Liderazgo , Investigación Cualitativa , Humanos , Cirugía General/educación , Femenino , Masculino , Adulto , Curriculum , Educación de Postgrado en Medicina/métodosRESUMEN
ABSTRACT: Severe traumatic brain injury (TBI) often initiates a systemic inflammatory response syndrome, which can potentially culminate into multiorgan dysfunction. A central player in this cascade is endotheliopathy, caused by perturbations in homeostatic mechanisms governed by endothelial cells due to injury-induced coagulopathy, heightened sympathoadrenal response, complement activation, and proinflammatory cytokine release. Unique to TBI is the potential disruption of the blood-brain barrier, which may expose neuronal antigens to the peripheral immune system and permit neuroinflammatory mediators to enter systemic circulation, propagating endotheliopathy systemically. This review aims to provide comprehensive insights into the "neuroendothelial axis" underlying endothelial dysfunction after TBI, identify potential diagnostic and prognostic biomarkers, and explore therapeutic strategies targeting these interactions, with the ultimate goal of improving patient outcomes after severe TBI.
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Lesiones Traumáticas del Encéfalo , Células Endoteliales , Humanos , Células Endoteliales/metabolismo , Lesiones Traumáticas del Encéfalo/terapia , Citocinas/metabolismo , Barrera Hematoencefálica/metabolismo , Activación de ComplementoRESUMEN
BACKGROUND: We have previously shown that partial REBOA (pREBOA) deployment in the thoracic aorta is safe for 2 to 4 hours, but it is unclear whether the distal blood flow after partial aortic occlusion would lead to ongoing hemorrhage. The objective of this study was to evaluate the hemostatic efficacy of pREBOA in a model of uncontrolled vascular injury. STUDY DESIGN: Female Yorkshire swine (n = 10, 40 to 45 kg) were anesthetized and instrumented. A through-and-through injury was created in the common iliac artery. The animals were randomly assigned to: (1) pREBOA-PRO deployment after 3 minutes and (2) control. Both groups were given normal saline resuscitation for hypotension. The pREBOA was adjusted to partial occlusion (distal mean arterial pressure of 30 mmHg), and then left without titration for 2 hours. Then, fresh frozen plasma was transfused and the vessel repaired. The balloon was deflated and the animals were monitored for 2 hours. In the critical care period, 2 L of normal saline was infused, norepinephrine was given for mean arterial pressure ≤55, and electrolytes and acidosis were corrected. Organs were examined for gross and histologic evidence of ischemic injuries. The primary endpoint was post-inflation blood loss. RESULTS: All the pREBOA animals survived until the end, whereas control animals had a mean survival time of 38.2 minutes (p < 0.05). The pREBOA group showed significantly less bleeding after balloon deployment (93.8 vs 1,980.0 mL, p < 0.05), and had appropriate lactate clearance, with minimal histologic distal organ ischemia. CONCLUSIONS: Partial aortic occlusion with the newly designed balloon can achieve the desired balance between effective hemorrhage control and adequate distal flow, without a need for ongoing balloon titration.
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Oclusión con Balón , Procedimientos Endovasculares , Choque Hemorrágico , Lesiones del Sistema Vascular , Porcinos , Femenino , Animales , Solución Salina , Modelos Animales de Enfermedad , Hemorragia/etiología , Hemorragia/terapia , ResucitaciónRESUMEN
BACKGROUND: It has previously been shown that administration of valproic acid (VPA) can improve outcomes if given within an hour following traumatic brain injury (TBI). This short therapeutic window (TW) limits its use in real-life situations. Based upon its pharmacokinetic data, we hypothesized that TW can be extended to 3 hours if a second dose of VPA is given 8 hours after the initial dose. METHOD: Yorkshire swine (40-45 kg; n = 10) were subjected to TBI (controlled cortical impact) and 40% blood volume hemorrhage. After 2 hours of shock, they were randomized to either (1) normal saline resuscitation (control) or (2) normal saline-VPA (150 mg/kg × two doses). First dose of VPA was started 3 hours after the TBI, with a second dose 8 hours after the first dose. Neurologic severity scores (range, 0-36) were assessed daily for 14 days, and brain lesion size was measured via magnetic resonance imaging on postinjury day 3. RESULTS: Hemodynamic and laboratory parameters of shock were similar in both groups. Valproic acid-treated animals had significantly less neurologic impairment on days 2 (16.3 ± 2.0 vs. 7.3 ± 2.8) and 3 (10.9 ± 3.6 vs. 2.8 ± 1.1) postinjury and returned to baseline levels 54% faster. Magnetic resonance imaging showed no differences in brain lesion size on day 3. Pharmacokinetic data confirmed neuroprotective levels of VPA in the circulation. CONCLUSION: This is the first study to demonstrate that VPA can be neuroprotective even when given 3 hours after TBI. This expanded TW has significant implications for the design of the clinical trial.
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Lesiones Traumáticas del Encéfalo , Choque Hemorrágico , Porcinos , Animales , Ácido Valproico/uso terapéutico , Choque Hemorrágico/tratamiento farmacológico , Solución Salina , Modelos Animales de Enfermedad , Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Resucitación/métodosRESUMEN
BACKGROUND: The clinical usage of the resuscitative endovascular balloon occlusion of the aorta (REBOA) is limited by distal ischemia resulting from complete aortic occlusion. We hypothesized that animals would physiologically tolerate the prolonged partial occlusion using the novel partially occluding REBOA (pREBOA) with survivable downstream injuries. METHODS: This study used the pREBOA-PRO catheter in a previously established swine model. Female Yorkshire swine (n = 10) underwent a volume-controlled hemorrhage (40% estimated blood). After 1 hour of shock (mean arterial pressure, 28-32 mm Hg), animals were randomized to partial occlusion for either 2 hours or 4 hours. The pREBOA was inflated in zone 1 to achieve partial occlusion defined as a distal systolic blood pressure (SBP) of 20 ± 2 mm Hg. The balloon was deflated at the end of the occlusion period, and animals were resuscitated for 2 hours. Tissues were examined for gross and histologic injury. The primary endpoint was histologic organ injury, and secondary end points were hemodynamic variables and degree of distal organ ischemia. RESULTS: All animals survived to the endpoint. Both groups had similar proximal and distal SBP at baseline, with a divergence of pressures ranging from 55 mm Hg to 90 mm Hg on inflation. The lactate levels increased throughout the occlusion and decreased approximately 40% during the observation period. More animals required norepinephrine and fluid in the 4-hour group compared with the 2-hour group. There was no gross small bowel ischemia noted in the 2-hour animals. The 4-hour group had surgically resectable patchy short segment ischemia. Neither group showed nonsurvivable organ ischemia on pathology or laboratory values. CONCLUSION: This is the first study showing that the zone 1 aorta can be occluded for over 4 hours using a new pREBOA device without need for balloon titration. In conclusion, simple changes in balloon design offer reliable partial aortic occlusion, with potentially survivable and surgically manageable downstream injuries.
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Oclusión con Balón , Procedimientos Endovasculares , Choque Hemorrágico , Animales , Femenino , Aorta/cirugía , Oclusión con Balón/métodos , Presión Sanguínea , Modelos Animales de Enfermedad , Procedimientos Endovasculares/métodos , Hemodinámica/fisiología , Hemorragia , Resucitación/métodos , Choque Hemorrágico/terapia , PorcinosRESUMEN
ABSTRACT: Injuries lead to an early systemic inflammatory state with innate immune system activation. Neutrophil extracellular traps (NETs) are a complex of chromatin and proteins released from the activated neutrophils. Although initially described as a response to bacterial infections, NETs have also been identified in the sterile postinjury inflammatory state. Peptidylarginine deiminases (PADs) are a group of isoenzymes that catalyze the conversion of arginine to citrulline, termed citrullination or deimination. PAD2 and PAD4 have been demonstrated to play a role in NET formation through citrullinated histone 3. PAD2 and PAD4 have a variety of substrates with variable organ distribution. Preclinical and clinical studies have evaluated the role of PADs and NETs in major trauma, hemorrhage, burns, and traumatic brain injury. Neutrophil extracellular trap formation and PAD activation have been shown to contribute to the postinjury inflammatory state leading to a detrimental effect on organ systems. This review describes our current understanding of the role of PAD and NET formation following injury and burn. This is a new field of study, and the emerging data appear promising for the future development of targeted biomarkers and therapies in trauma.
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Trampas Extracelulares , Desiminasas de la Arginina Proteica/genética , Desiminasas de la Arginina Proteica/metabolismo , Trampas Extracelulares/metabolismo , Citrulinación , Neutrófilos/metabolismo , Histonas/metabolismoRESUMEN
OBJECTIVE: Sonographers performing venous duplex ultrasound (VDUS) of patients with coronavirus disease 2019 (COVID-19) have an increased risk of exposure owing to their close contact with these patients for an extended period. The objective of the present study was to evaluate the efficacy of a modified COVID-19 VDUS protocol to reduce sonographer exposure to COVID-19 patients. METHODS: We performed a single-center retrospective review. Patients who had undergone VDUS under the modified COVID-19 protocol between March 1, 2020, and June 30, 2020, with a confirmed or presumed COVID-19 diagnosis at the VDUS were included. The modified COVID-19 protocol was defined as the ability of the sonographer to terminate the examination on detection of an acute deep vein thrombosis (DVT). The primary outcome measures were the number of anatomic deep venous segments recorded by the sonographer, which was used as a surrogate measure for sonographer exposure time, and the number of acute DVTs found on follow-up examinations in segments not visualized at the index VDUS. RESULTS: A total of 160 lower extremity VDUS (LEVDUS) scans and 72 upper extremity VDUS (UEVDUS) scans were performed using the modified COVID-19 protocol. The index VDUS had found an acute DVT for 44 of 160 patients (27.5%) who had undergone LEVDUS and 26 of 72 (36.6%) who had undergone UEVDUS. On follow-up imaging, 7 of 38 LEVDUS scans (17.9%) and 1 of 10 UEVDUS scans (10%) had demonstrated a new acute DVT. Malignancy and surgery 30 days before imaging were significantly associated with acute lower extremity DVT, and mechanical ventilation and extracorporeal membrane oxygenation were associated with acute upper extremity DVT. On the index VDUS, the average was 10.6 of 12 total visualized segments on LEVDUS and 6.4 of 10 total segments on UEVDUS. Of the index VDUS scans, 35.6% of the LEVDUS and 78.6% of the UEVDUS scans had been abbreviated. The index VDUS scans that were positive for acute DVT had had significantly fewer visualized segments for both lower (8.4 vs 11.5; P < .0001) and upper (4.2 vs 7.6) extremities (P < .0001). On the follow-up examinations, only one of eight new acute DVTs had been found in a patient whose index VDUS had been abbreviated and the corresponding segment not assessed. These findings did not affect the patient's clinical course. CONCLUSIONS: The modified COVID-19 VDUS protocol reduced sonographers' potential exposure time to COVID-19. Additionally, the clinical efficacy was maintained, with no missed DVTs, despite the abbreviation of the VDUS examinations.
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COVID-19 , Trombosis de la Vena , Humanos , Prueba de COVID-19 , COVID-19/complicaciones , Ultrasonografía Doppler Dúplex , Trombosis de la Vena/diagnóstico por imagen , Trombosis de la Vena/etiología , Trombosis de la Vena/terapia , Venas , Estudios RetrospectivosRESUMEN
INTRODUCTION: Tranexamic acid (TXA) is a standard component of Tactical Combat Casualty Care. Recent retrospective studies have shown that TXA use is associated with a higher rate of venous thromboembolic (VTE) events in combat-injured patients. We aim to determine if selective administration should be considered in the prolonged field care environment. MATERIALS AND METHODS: We performed a systematic review using the 2020 Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Clinical trials and observational studies of combat casualties published between January 1, 1960, and June 20, 2022, were included. We analyzed survival and VTE outcomes in TXA recipients and non-recipients. We discussed the findings of each paper in the context of current and future combat environments. RESULTS: Six articles met criteria for inclusion. Only one study was powered to report mortality data, and it demonstrated a 7-fold increase in survival in severely injured TXA recipients. All studies reported an increased risk of VTE in TXA recipients, which exceeded rates in civilian literature. However, five of the six studies used overlapping data from the same registry and were limited by a high rate of missingness in pertinent variables. No VTE-related deaths were identified. CONCLUSIONS: There may be an increased risk of VTE in combat casualties that receive TXA; however, this risk must be considered in the context of improved survival and an absence of VTE-associated deaths. To optimize combat casualty care during prolonged field care, it will be essential to ensure the timely administration of VTE chemoprophylaxis as soon as the risk of significant hemorrhage permits.
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Antifibrinolíticos , Ácido Tranexámico , Tromboembolia Venosa , Trombosis de la Vena , Humanos , Ácido Tranexámico/efectos adversos , Antifibrinolíticos/efectos adversos , Tromboembolia Venosa/tratamiento farmacológico , Trombosis de la Vena/complicaciones , Hemorragia/etiologíaRESUMEN
Mitochondrial dynamics are central to the pathophysiology of cellular damage and inflammatory responses. In the context of solid organ transplantation, mitochondria are implicated in immune activation in donor organs that occurs after brain death, as they are critical to the regulation of cellular stress response, cell death, and display energetic adaptations through the adjustment of respiratory capacity depending on the cellular milieu. Mitochondrial damage activates mitochondrial systems of fission, fusion, biogenesis, and mitochondrial autophagy, or mitophagy. The mechanistic pathways as well as therapies targeting mitochondrial physiology have been studied as plausible ways to mitigate the negative effects of brain death on donor organs, though there is no summative evaluation of the multiple efforts across the field. This mini-review aims to discuss the interplay of donor brain death, mitochondrial dynamics, and impact on allograft function as it pertains to heart, lung, liver, and kidney transplants.
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OBJECTIVE: The COVID-19 pandemic has played a lasting role on residency recruitment through the virtual interview process. The objective of this study was to 1) examine general surgery applicants' priorities and perceptions following pre-interview virtual open houses and 2) to assess applicant expectations and efficacy of the virtual interview day process. DESIGN/SETTING/PARTICIPANTS: This study utilized two voluntary and anonymous cross-sectional surveys administered via email to evaluate the virtual interview process of a general surgery residency program. The first was administered to registrants following completion of three open houses of various topics. The second was administered following each interview day. The post-open house survey had 78 respondents, two excluded for no open house attendance. The post-interview survey was completed by 44 applicants (62.9% response rate). RESULTS: Majority of respondents reported that attending virtual open houses made them want to apply to (90.9%) and improved their perception of the program (94.7%). Applicants who felt a sense of obligation to attend open houses (68.4%) were significantly more likely to feel that they contributed to the stress and time commitment of applications (81.8% vs 18.2%, p=0.028). Interview expectations were identified in recurrent themes: 1. Clear organization with breaks, 2. Interactive resident sessions, 3. Meetings with program leadership, 4. Additional information unavailable on other resources. The pre-interview social and interview day improved 90.2% of the applicants' perceptions of the program. The interview significantly improved applicants' ability to assess nearly all aspects of the program, notably resident camaraderie and culture (30.8% vs 97.4%, p=0.01) and strengths and weaknesses (30.8% vs 92.3%, p=0.04). CONCLUSIONS: While virtual open houses can improve applicants' perceptions and desire to apply to a program, the associated stress and obligation should be considered. Virtual interviews should provide information unavailable using other resources and provide avenues for conveying the resident culture and camaraderie.
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COVID-19 , Internado y Residencia , Humanos , Estudios Transversales , Motivación , Pandemias , COVID-19/epidemiologíaRESUMEN
BACKGROUND: MG53, a member of the tripartite motif (TRIM) protein family, plays an essential role in cell membrane repair and promotes cell survival. Recent studies show that systemic delivery of recombinant human MG53 (rhMG53) protein markedly attenuates tissue injury/inflammation, and facilitates healing. This study was performed to test whether intravenous administration of rhMG53 protein would decrease the lesion size in a clinically relevant large animal model of traumatic brain injury (TBI). METHOD: Yorkshire swine (40-45 kg; n = 5/group) were subjected to controlled cortical impact TBI and randomized to either: (1) rhMG53 protein (2 mg/kg, intravenous) or (2) normal saline control. Hemodynamics, intracranial pressure, and brain oxygenation were monitored for 7 hours. Brains were then harvested and sectioned into 5-mm slices and stained with 2,3,5-triphenyltetrazolium chloride to quantify the lesion size. Blood-brain barrier permeability of MG53 in the brain was determined by Western blot and immunohistochemistry. Bcl-2 and phospho-GSK ß levels were measured as makers of prosurvival pathway activation. RESULTS: Hemodynamic parameters were similar in both groups, but the lesion size in the rhMG53-treated group (2,517 ± 525.4 mm 3 ) was significantly ( p < 0.05) smaller than the control group (3,646 ± 740.1 mm 3 ). In the treated animals, rhMG53 was detected in the regions surrounding the TBI, but it was absent in the saline-treated control animals. Bcl-2 and phospho-GSK ß levels in the brains were upregulated in the rhMG53-treated animals. CONCLUSION: Intravenously administered rhMG53 localizes to the injured areas of the brain, with the treated animals demonstrating a significant attenuation in the brain lesion size following TBI.
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Lesiones Traumáticas del Encéfalo , Humanos , Animales , Porcinos , Modelos Animales de Enfermedad , Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Encéfalo , Presión Intracraneal , Inflamación , Proteínas Proto-Oncogénicas c-bcl-2RESUMEN
INTRODUCTION: Chemotherapy is increasingly administered prior to resection in patients with early-stage pancreatic adenocarcinoma, but the national prevalence of this practice is poorly understood. Our objectives were to (1) describe the utilization of upfront chemotherapy management of stage I pancreatic cancer; (2) define factors associated with the use of upfront chemotherapy and subsequent resection; and (3) assess hospital-level variability in upfront chemotherapy and subsequent resection. METHODS: The National Cancer Database was used to identify patients treated for clinical stage I pancreatic adenocarcinoma. Outcomes were receipt of upfront chemotherapy and surgical resection after upfront chemotherapy. Associations between patient/hospital factors and both initial management and subsequent resection were assessed by multivariable logistic regression. RESULTS: A total of 17,495 patients were included, with 26.6% receiving upfront chemotherapy. Upfront chemotherapy was more likely in patients who were ≥ 80 years of age (odds ratio [OR] 1.64, 95% confidence interval [CI] 1.39-1.93), had T2 tumors (OR 2.56, 95% CI 2.36-2.78), or were treated at a low-volume center (OR 2.10, 95% CI 1.63-2.71). Among patients receiving upfront chemotherapy, only 33.5% underwent subsequent resection. Resection was more likely in patients with T1 tumors (OR 1.22, 95% CI 1.04-1.43) and in those treated at high-volume centers (OR 4.03, 95% CI 2.90-5.60). Only 20.4% of hospitals performed resection in > 50% of patients after upfront chemotherapy. CONCLUSION: Rates of surgical resection after upfront chemotherapy are relatively low, and the proportion of patients who eventually undergo resection varies considerably between hospitals. The use of surgery after upfront chemotherapy in resectable pancreatic cancer should be considered as an internal quality-of-cancer-care measure.
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Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia Adyuvante/métodos , Pancreatectomía/estadística & datos numéricos , Neoplasias Pancreáticas/tratamiento farmacológico , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Anciano , Anciano de 80 o más Años , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Células Tumorales CultivadasRESUMEN
GOAL: To evaluate the relationship between the ACS Risk Calculator and NSQIP expected outcomes in elective colorectal resections. METHODS: The 2015 NSQIP morbidity report for elective colorectal procedures at a single institution was evaluated. Risk Calculator (RC) reports were completed for predicted risk. Correlation coefficients were calculated for the general relationship between the tools for complications. Receiver operator characteristic (ROC) curves compared the predictive accuracy of the tools to actual outcome measures of any complication, serious complications, readmissions, unplanned return to the operating room, and mortality. RESULTS: There was high correlation between NSQIP and the RC for any complication, but low correlation for serious complications. Predictive accuracy of both tools for identifying actual occurrences was poor, with area under the ROC<0.60 for all metrics with both tools, except NSQIP mortality, which had good accuracy. CONCLUSIONS: The tools were highly correlated for predicting complications in general, but neither was accurate for predicting actual outcomes. As underestimating risk and complications could have financial implications under value-based care, refinement could benefit informed consent and quality improvement at the institutional level.