High rates of respiratory illnesses upon arrival: lessons from Team USA at the Santiago 2023 Pan American and Parapan American Games.

OBJECTIVE: To describe the incidence and characteristics of injuries and illnesses among Team USA athletes competing at the Santiago 2023 Pan American Games (PAG) and Parapan American Games (PPAG), with a particular focus on the incidence of respiratory illnesses and on injuries for sports new to the Olympic and Paralympic programmes. METHODS: Illnesses and injuries occurring among the 870 Team USA athletes competing in the Santiago 2023 PAG or PPAG were documented within Team USA's Injury and Illness Surveillance system. Illness and injury incidence per 1000 athlete-days (ADs) and incidence ratios (IR) were calculated, both with 95% CIs. RESULTS: Illness (IR 2.5, 95% CI 1.6, 3.9) and injury (IR 1.8, 95% CI 1.3, 2.5) rates were greater during PPAG compared with PAG. Illness rates were higher in the pre-opening ceremony period compared with the competition period for both PAG (IR 2.7, 95% CI 1.1, 5.9) and PPAG (IR 1.9, 95% CI 0.9, 3.8). Respiratory illness was the most common illness with 3.2% and 8.9% of all Team USA athletes reporting a respiratory illness during the PAG and PPAG, respectively. Sports that are relatively new to the Olympic/Paralympic programmes exhibited the highest injury rates during the Games: breaking (250.0 (91.7, 544.2) per 1000 ADs), Para taekwondo (93.8 (19.3, 274.0) per 1000 ADs) and surfing (88.9 (24.2, 227.6) per 1000 ADs). CONCLUSION: Respiratory illness rates were the most common type of illness during both PAG and PPAG and were more likely to occur prior to competition starting. Our data have identified high injury risk populations (breaking, surfing, Para taekwondo) and timing (pre-opening ceremony period) for further risk factor analysis.

A Multicenter Evaluation of a Firearm Safety Intervention in the Pediatric Outpatient Setting.

PURPOSE: Firearm injuries continue to be a common cause of injury for American children. This pilot study was developed to evaluate the feasibility of providing guidance about firearm safety to the parents of pediatric patients using a tablet-based module in the outpatient setting. METHODS: A tablet-based questionnaire that included a firearm safety message based on current best practice was administered to parents of pediatric patients at nine centers in 2018. Parents were shown a firearm safety video and then asked a series of questions related to firearm safety. RESULTS: The study was completed by 543 parents from 15 states. More than one-third (37%) of families kept guns in their home. The majority of parents (81%, n = 438) thought it was appropriate for physicians to provide firearm safety counseling. Two-thirds (63%) of gun owning parents who do not keep their guns locked said that the information provided in the module would change the way they stored firearms at home. CONCLUSION: Use of a tablet based firearm safety module in the outpatient setting is feasible, and the majority of parents are receptive to receiving anticipatory guidance on firearm safety. Further data is needed to evaluate whether the intervention will improve firearm safety practices in the home. LEVEL OF EVIDENCE: Level III.

Major Barbara Stimson: A Historical Perspective on the American Board of Surgery Through the Accomplishments of the First Woman to Achieve Board Certification.

: Dr. Barbara Bartlett Stimson, AB, MD, MedScD, FACS (1898-1986) was a pioneering orthopedic surgeon from a prominent American family who, in 1940, became the first woman certified by the American Board of Surgery (ABS, certificate number 860). It would be another 7 years and approximately 2500 candidates before the next female surgeon would be certified. A member of the third class to admit women to Columbia Medical School and the second female surgical resident to complete training at Columbia-Presbyterian Medical Center, Dr. Stimson was a confident and exceptionally accomplished trailblazer for women in surgery. In this biographical sketch based upon documents from the ABS, and the archives of Vassar College and the College of Physicians and Surgeons at Columbia-Presbyterian Medical Center, Dr. Stimson's motivations, attitudes, and unique accomplishments emerge as testimony to the exceptional career of this driven, self-possessed woman. Stimson was undaunted by the sex-based conventions of her time, and achieved a notable career as a surgeon in the profession she loved; first honing her skills at a busy urban fracture service in New York, then serving with distinction in the Royal Army Medical Corps during World War II, and finally returning to the states to become a respected leader in her field. Her life story and unprecedented ABS certification affirm her conviction that proven skill and ability can be used as a means of overcoming unfounded biases, and helped pave the way for future generations of board certified female surgeons in the United States.

Optimizing physician skill development for medical students: The four-part assessment.

BACKGROUND: Medical student performance has been poorly correlated with residency performance and warrants further investigation. We propose a novel surgical assessment tool to determine correlations with clinical aptitude. METHODS: Retrospective review of medical student assessments from 2013 to 2015. Faculty rating of student performance was evaluated by: 1) case presentation, 2) problem definition, 3) question response and 4) use of literature and correlated to final exam assessment. A Likert scale interrater reliability was evaluated. RESULTS: Sixty student presentations were scored (4.8 assessors/presentation). A student's case presentation, problem definition, and question response was correlated with performance (r = 0.49 to 0.61, p ≤ 0.003). Moderate correlations for either question response or use of literature was demonstrated (0.3 and 0.26, p < 0.05). CONCLUSION: Our four-part assessment tool identified correlations with course and examination grades for medical students. As surgical education evolves, validated performance and reliable testing measures are required.

Splenectomy is associated with higher infection and pneumonia rates among trauma laparotomy patients.

Splenectomy increases lifetime risk of thromboembolism (VTE) and is associated with long-term infectious complications, primarily, overwhelming post-splenectomy infection (OPSI). Our objective was to evaluate risk of VTE and infection at index hospitalization post-splenectomy. Retrospective review of all patients who received a laparotomy in the NTDB. Propensity score matching for splenectomy was performed, based on ISS, abdominal abbreviated injury score >3, GCS, sex and mechanism. Major complications, VTE, and infection rates were compared. Multiple logistic regression models were utilized to evaluate splenectomy-associated complications. 93,221 laparotomies were performed and 17% underwent splenectomy. Multiple logistic regression models did not demonstrate an association between splenectomy and major complications (OR 0.96, 95% CI 0.91-1.03, p = 0.25) or VTE (OR 1.05, 95% CI 0.96-1.14, p = 0.33). Splenectomy was independently associated with infection (OR 1.07, 95% CI 1.00-1.14, p = 0.045). Subgroup analysis of patients with infection demonstrated that splenectomy was most strongly associated with pneumonia (OR 1.41, 95% CI 1.26-1.57, p < 0.001). Splenectomy is not associated with higher overall complication or VTE rates during index hospitalization. However, splenectomy is associated with a higher rate of pneumonia.

A multidisciplinary initiative to standardize intensive care to acute care transitions.

QUALITY ISSUE: Transfers from intensive care units to acute care units represent a complex care transition for hospitalized patients. Within our institution, variation in transfer practices resulted in unpredictable processes in which patient safety concerns were raised. INITIAL ASSESSMENT: Key stakeholders were engaged across the institution. Patient safety ('incident') reports and a staff survey identified safety concerns. CHOICE OF A SOLUTION: Using lean methodology, current transfer processes were mapped for the four adult intensive care units and waste was identified. During a summit of key stakeholders an ideal transfer process was conceived and a structured handoff tool (checklist) was developed. A daily management system (DMS) was implemented to monitor adherence. EVALUATION: The primary process outcome was adherence to the standardized workflow. Audits at 4, 8, and 12 months after implementation indicated that the checklist was used for 100% of transfers. Secondary outcomes included the percentage of transfers completed within a pre-specified time window of 120 minutes, provider notification of patient arrival on the acute care unit, and staff survey responses assessing adequacy of transfer communication. LESSONS LEARNED: Prior work has shown that structuring handoffs can improve patient safety, but the novelty of this project was addressing the transfer process in its entirety, across silos of care. Factors leading to the success of this project were the involvement of key stakeholders across the entire institution early in the project development phase, employment of lean methodology, and implementation of tools to guide workflow adherence and track causes of deviation from the workflow.

Performance improvement and patient safety program-guided quality improvement initiatives can significantly reduce computed tomography imaging in pediatric trauma patients.

BACKGROUND: Morbidity and mortality of cervical spine (C-spine) injury in pediatric trauma patients are high, necessitating quick and accurate diagnosis. Best practices emphasize minimizing radiation exposure through decreased reliance on computed tomography (CT), instead using clinical assessment, physical examination, and alternate imaging techniques. We implemented an institutional performance improvement and patient safety (PIPS) program initiative for C-spine clearance in 2010 because of high rates of CT scans among pediatric trauma patients. METHODS: A retrospective review of pediatric trauma patients, aged 0 years to 14 years, in the pre- and post-PIPS implementation periods was conducted. Rates of C-spine CT, overall CT, other imaging modalities, radiation exposure, patient characteristics, and injury severity were compared, and compliance with PIPS protocol was reviewed. RESULTS: Patient characteristics and injury severity were similar before and after PIPS implementation. C-spine CT rates decreased significantly between groups (30% vs. 13%, p < 0.001), whereas C-spine plain x-ray rates increased significantly (7% vs. 25%, p < 0.001). There was no difference in C-spine magnetic resonance imaging between groups (12% vs. 10%, p = 0.11). In 2007, 71% of patients received a CT scan for any reason. However, the overall CT rate decreased significantly between groups (60% vs. 45%, p < 0.001). There was an estimated 22% decrease in lifetime attributable risk (LAR) for any cancer due to ionizing imaging exposure in males and 38% decrease in females between the pre- and post-PIPS groups. There was a 54% decrease in LAR for thyroid cancer in males and females between groups; 2014 compliance with the protocol was excellent (82-90% per quarter). CONCLUSIONS: Performance improvement and patient safety program-generated protocol can significantly decrease ionizing radiation exposure. We demonstrate that a simple protocol focused on C-spine imaging has high compliance, decreased C-spine CT scans, and decreased LAR for thyroid cancer. A secondary benefit is a reduction in total CT imaging, with an associated decrease in LAR for all cancers. LEVEL OF EVIDENCE: Therapeutic study, level IV; diagnostic study, level III.

The Impact of Pre-Hospital Administration of Lactated Ringer's Solution versus Normal Saline in Patients with Traumatic Brain Injury.

Lactated Ringer's (LR) and normal saline (NS) are both used for resuscitation of injured patients. NS has been associated with increased resuscitation volume, blood loss, acidosis, and coagulopathy compared with LR. We sought to determine if pre-hospital LR is associated with improved outcome compared with NS in patients with and without traumatic brain injury (TBI). We included patients receiving pre-hospital LR or NS from the PRospective Observational Multicenter Major Trauma Transfusion (PROMMTT) study. Patients with TBI (Abbreviated Injury Scale [AIS] head ≥3) and without TBI (AIS head ≤2) were compared. Cox proportional hazards models including Injury Severity Score (ISS), AIS head, AIS extremity, age, fluids, intubation status, and hospital site were generated for prediction of mortality. Linear regression models were generated for prediction of red blood cell (RBC) and crystalloid requirement, and admission biochemical/physiological parameters. Seven hundred ninety-one patients received either LR (n = 117) or NS (n = 674). Median ISS, AIS head, AIS extremity, and pre-hospital fluid volume were higher in TBI and non-TBI patients receiving LR compared with NS (p < 0.01). In patients with TBI (n = 308), LR was associated with higher adjusted mortality compared with NS (hazard rate [HR] = 1.78, confidence interval [CI] 1.04-3.04, p = 0.035). In patients without TBI (n = 483), no difference in mortality was demonstrated (HR = 1.49, CI 0.757-2.95, p = 0.247). Fluid type had no effect on admission biochemical or physiological parameters, 6-hour RBC, or crystalloid requirement in either group. LR was associated with increased mortality compared with NS in patients with TBI. These results underscore the need for a prospective randomized trial comparing pre-hospital LR with NS in patients with TBI.

A Clinical Tool for the Prediction of Venous Thromboembolism in Pediatric Trauma Patients.

IMPORTANCE: Although rare, the incidence of venous thromboembolism (VTE) in pediatric trauma patients is increasing, and the consequences of VTE in children are significant. Studies have demonstrated increasing VTE risk in older pediatric trauma patients and improved VTE rates with institutional interventions. While national evidence-based guidelines for VTE screening and prevention are in place for adults, none exist for pediatric patients, to our knowledge. OBJECTIVES: To develop a risk prediction calculator for VTE in children admitted to the hospital after traumatic injury to assist efforts in developing screening and prophylaxis guidelines for this population. DESIGN, SETTING, AND PARTICIPANTS: Retrospective review of 536,423 pediatric patients 0 to 17 years old using the National Trauma Data Bank from January 1, 2007, to December 31, 2012. Five mixed-effects logistic regression models of varying complexity were fit on a training data set. Model validity was determined by comparison of the area under the receiver operating characteristic curve (AUROC) for the training and validation data sets from the original model fit. A clinical tool to predict the risk of VTE based on individual patient clinical characteristics was developed from the optimal model. MAIN OUTCOME AND MEASURE: Diagnosis of VTE during hospital admission. RESULTS: Venous thromboembolism was diagnosed in 1141 of 536,423 children (overall rate, 0.2%). The AUROCs in the training data set were high (range, 0.873-0.946) for each model, with minimal AUROC attenuation in the validation data set. A prediction tool was developed from a model that achieved a balance of high performance (AUROCs, 0.945 and 0.932 in the training and validation data sets, respectively; P = .048) and parsimony. Points are assigned to each variable considered (Glasgow Coma Scale score, age, sex, intensive care unit admission, intubation, transfusion of blood products, central venous catheter placement, presence of pelvic or lower extremity fractures, and major surgery), and the points total is converted to a VTE risk score. The predicted risk of VTE ranged from 0.0% to 14.4%. CONCLUSIONS AND RELEVANCE: We developed a simple clinical tool to predict the risk of developing VTE in pediatric trauma patients. It is based on a model created using a large national database and was internally validated. The clinical tool requires external validation but provides an initial step toward the development of the specific VTE protocols for pediatric trauma patients.

Respiratory depression in the intoxicated trauma patient: are opioids to blame?

Providing effective pain management to acutely intoxicated trauma patients represents a challenge of balancing appropriate pain management with the risk of potential respiratory depression from opioid administration. The objective of this study was to quantify the incidence of respiratory depression in trauma patients acutely intoxicated with ethanol who received opioids as compared with those who did not and identify potential risk factors for respiratory depression in this population. Retrospective medical record review was conducted for subjects identified via the trauma registry who were admitted as a trauma activation and had a detectable serum ethanol level upon admission. Risk factors and characteristics compared included demographics, Injury Severity Score, Glasgow Coma Score, serum ethanol level upon arrival, urine drug screen results, incidence of respiratory depression, and opioid and other sedative medication use. A total of 233 patients were included (78.5% male). Patients who received opioids were more likely to have a higher Injury Severity Score and initial pain score on admission as compared with those who did not receive opioids. Blood ethanol content was higher in patients who did not receive opioids (0.205 vs 0.237 mg/dL, P = .015). Patients who did not receive opioids were more likely to be intubated within 4 hours of admission (1.7% vs 12.1%, P = .02). Opioid administration was not associated with increased risk of respiratory depression (19.7% vs 22.4%, P = .606). Increased cumulative fentanyl dose was associated with increased risk of respiratory depression. Increased cumulative fentanyl dose, but not opioid administration alone, was found to be a risk factor for respiratory depression.

Traumatic diaphragmatic injury in the American College of Surgeons National Trauma Data Bank: a new examination of a rare diagnosis.

BACKGROUND: Traumatic diaphragmatic injury (TDI) is a rarely diagnosed injury in trauma. Previous studies have been limited in their evaluation of TDI because of small population size and center bias. Although injuries may be suspected based on penetrating mechanism, blunt injuries may be particularly difficult to detect. The American College of Surgeons National Trauma Data Bank is the largest trauma database in the United States. We hypothesized that we could identify specific injury patterns associated with blunt and penetrating TDIs. METHODS: We examined demographics, diagnoses, mechanism of injury, and outcomes for patients with TDI in 2012 as this is the largest and most recent dataset available. Comparisons were made using chi-square or independent samples t test. RESULTS: There were a total of 833,309 encounters in the National Trauma Data Bank in 2012. Three thousand eight hundred seventy-three patients had a TDI (.46%). Of those, 1,240 (33%) patients had a blunt mechanism and 2,543 (67%) had a penetrating mechanism. Patients with blunt TDI were older (44 ± 19 vs 31 ± 13 years, P < .001), had a higher injury severity score (33 ± 14 vs 24 ± 15, P < .001), and a higher mortality rate (19.8% vs 8.8%, P < .001). Compared with patients with penetrating injuries, those with blunt TDI were more likely to have injuries to the thoracic aorta (2.9% vs .5%, P < .001), lung (48.7% vs 28.1, P < .001), bladder (5.9% vs .7%, P < .001), and spleen (44.8% vs 29.1%, P < .001). Penetrating TDI was associated with liver and hollow viscus injuries. CONCLUSIONS: Diaphragmatic injury is an uncommon but significant diagnosis in trauma patients. Blunt injuries may be more likely to be occult; however, a pattern of associated injuries to the aorta, lung, spleen, and bladder should prompt further workup for TDI.

A flexible postoperative debriefing process can effectively provide formative resident feedback.

BACKGROUND: Providing residents with formative operative feedback is one of the ongoing challenges in modern surgical education. This is highlighted by the recent American Board of Surgery requirement for formal operative assessments. A flexible and adaptable procedure feedback process may allow attending surgeons to provide qualitative and quantitative feedback to residents while encouraging surgeons-in-training to critically reflect on their own performance. STUDY DESIGN: We designed and implemented a flexible feedback process in which residents initiated a postoperative feedback discussion and completed a Procedure Feedback Form (PFF) with their supervising attending surgeon. Comparisons were made between the quantitative and qualitative assessments of attending and resident surgeons. Free text statements describing strengths and weaknesses were analyzed using grounded theory with constant comparison. RESULTS: We identified 346 assessments of 48 surgery residents performing 38 different cases. There was good inter-rater reliability between resident and attending surgeons' quantitative assessment, Goodman and Kruskal gamma > 0.65. Key themes identified on qualitative analysis included flow, technique, synthesis/decision, outcomes, knowledge, and communication/attitudes. Subthematic analysis demonstrated that our novel debriefing procedure was easily adaptable to a wide variety of clinical settings and grew more individualized for senior learners. CONCLUSIONS: This procedure feedback process is easily adaptable to a wide variety of cases and supports resident self-reflection. The process grows in nuance and complexity with the learner and may serve as a guide for a flexible and widely applicable postoperative feedback process.

Optimal timing of femur fracture stabilization in polytrauma patients: A practice management guideline from the Eastern Association for the Surgery of Trauma.

BACKGROUND: Femur fractures are common among trauma patients and are typically seen in patients with multiple injuries resulting from high-energy mechanisms. Internal fixation with intramedullary nailing is the ideal method of treatment; however, there is no consensus regarding the optimal timing for internal fixation. We critically evaluated the literature regarding the benefit of early (<24 hours) versus late (>24 hours) open reduction and internal fixation of open or closed femur fractures on mortality, infection, and venous thromboembolism (VTE) in trauma patients. METHODS: A subcommittee of the Practice Management Guideline Committee of the Eastern Association for the Surgery of Trauma conducted a systematic review and meta-analysis for the earlier question. RevMan software was used to generate forest plots. Grading of Recommendations, Assessment, Development, and Evaluations methodology was used to rate the quality of the evidence, using GRADEpro software to create evidence tables. RESULTS: No significant reduction in mortality was associated with early stabilization, with a risk ratio (RR) of 0.74 (95% confidence interval [CI], 0.50-1.08). The quality of evidence was rated as "low." No significant reduction in infection (RR, 0.4; 95% CI, 0.10-1.6) or VTE (RR, 0.63; 95% CI, 0.37-1.07) was associated with early stabilization. The quality of evidence was rated "low." CONCLUSION: In trauma patients with open or closed femur fractures, we suggest early (<24 hours) open reduction and internal fracture fixation. This recommendation is conditional because the strength of the evidence is low. Early stabilization of femur fractures shows a trend (statistically insignificant) toward lower risk of infection, mortality, and VTE. Therefore, the panel concludes the desirable effects of early femur fracture stabilization probably outweigh the undesirable effects in most patients.

Acupuncture-Related Pneumothorax.

Background: Acupuncture-related pneumothorax (PTX) is a poorly reported complication of thoracic needling. Recent Chinese literature reviews cited PTXs as the most common adverse outcome. Because of delayed presentation, this complication is thought to be underrecognized by acupuncturists and is largely addressed by hospital and emergency room personnel. The goal of this case study was to demonstrate common risk factors for a PTX, the mechanisms for its development, and protocols to use if one is suspected. Case: A 43-year-old, athletic female with chronic neck pain that was poorly managed with oral medications sought an alternative intervention for pain control. Her treatment plan consisted of weekly acupuncture sessions in the prone and supine positions targeting points along the Bladder, Gall Bladder, and Small Intestine meridians, as well as the right scapular Ah Shi point. She also received infrared lamp therapy. The aim of this approach was to help the patient achieve subjective pain reduction and increased range of motion. Results: One hour after her third treatment session, this patient experienced pleuritic chest pain and dyspnea. She was transported to a local Level-1 trauma center by emergency medical services and was diagnosed with a right-sided PTX. Conclusions: The acupoints addressed, a practitioner's knowledge of variations in anatomy, and a patient's body habitus and medical history are risk factors for PTX development. A patient's initial presentation does not predict future outcome. A benign presentation can evolve into a potentially life-threatening cardiovascular collapse. When PTX is suspected, discussing it with the patient and facilitating appropriate evaluation and intervention by a tertiary-care facility is warranted.

Cryopreserved red blood cells are superior to standard liquid red blood cells.

BACKGROUND: Liquid preserved packed red blood cell (LPRBC) transfusions are used to treat anemia and increase end-organ perfusion. Throughout their storage duration, LPRBCs undergo biochemical and structural changes collectively known as the storage lesion. These changes adversely affect perfusion and oxygen off-loading. Cryopreserved RBCs (CPRBC) can be stored for up to 10 years and potentially minimize the associated storage lesion. We hypothesized that CPRBCs maintain a superior biochemical profile compared with LPRBCs. METHODS: This was a prospective, randomized, double-blinded study. Adult trauma patients with an Injury Severity Score (ISS) greater than 4 and an anticipated 1-U to 2-U transfusion of PRBCs were eligible. Enrolled patients were randomized to receive either CPRBCs or LPRBCs. Serum proteins (haptoglobin, serum amyloid P, and C-reactive protein), proinflammatory and anti-inflammatory cytokines, d-dimer, nitric oxide, and 2,3-DPG concentrations were analyzed. Mann-Whitney U-test and Wilcoxon rank sum test were used to assess significance (p < 0.05). RESULTS: Fifty-seven patients were enrolled (CPRBC, n = 22; LPRBC, n = 35). The LPRBC group's final interleukin 8, tumor necrosis factor α, and d-dimer concentrations were elevated compared with their pretransfusion values (p < 0.05). After the second transfused units, 2,3-DPG was higher in the patients receiving CPRBCs (p < 0.05); this difference persisted throughout the study. Finally, serum protein concentrations were decreased in the transfused CPRBC units compared with LPRBC (p < 0.01). CONCLUSION: CPRBC transfusions have a superior biochemical profile: an absent inflammatory response, attenuated fibrinolytic state, and increased 2,3-DPG. A blood banking system using both storage techniques will offer the highest-quality products to critically injured patients virtually independent of periodic changes in donor availability and transfusion needs. LEVEL OF EVIDENCE: Therapeutic study, level II.

A systematic approach to basic chest radiograph interpretation: a cardiovascular focus.

In this column, I will provide a general overview to the indications and basic chest radiograph features such as density, views and technical quality. A systematic approach to radiographic interpretation is outlined. This proposed approach follows anatomical structures organized in alphabetical order (airway, bone, cardiac, diaphragm, extras and frame), while considering a range of pathophysiological findings. Common cardiovascular findings reviewed include atelectasis, pneumothorax, pleural effusions, congestive heart failure, pulmonary edema, consolidation and pneumonia. While chest radiography is an important diagnostic tool for monitoring patients, correlation to the patient's clinical assessment is always required.

Correlation of missed doses of enoxaparin with increased incidence of deep vein thrombosis in trauma and general surgery patients.

IMPORTANCE: Enoxaparin sodium is widely used for deep vein thrombosis (DVT) prophylaxis, yet DVT rates remain high in the trauma and general surgery populations. Missed doses during hospitalization are common. OBJECTIVE: To determine if missed doses of enoxaparin correlate with DVT formation. DESIGN, SETTING, AND PARTICIPANTS: Data were prospectively collected among 202 trauma and general surgery patients admitted to a level I trauma center. MAIN OUTCOMES AND MEASURES: Deep vein thrombosis screening was performed using a rigorous standardized protocol. RESULTS: The overall incidence of DVT was 15.8%. In total, 58.9% of patients missed at least 1 dose of enoxaparin. The DVTs occurred in 23.5% of patients who missed at least 1 dose and in 4.8% of patients who did not (P < .01). On univariate analysis, the need for mechanical ventilation (71.8% vs 44.1%), the performance of more than 1 operation (59.3% vs 40.0%), and male sex (75% vs 56%) were associated with DVT formation (P < .05 for all). A bivariate logistic regression was then performed, which revealed age 50 years or older and interrupted enoxaparin therapy as the only independent risk factors for DVT formation. The DVT rate did not differ between trauma and general surgery populations or in patients receiving once-daily vs twice-daily dosing regimens. CONCLUSIONS AND RELEVANCE: Interrupted enoxaparin therapy and age 50 years or older are associated with DVT formation among trauma and general surgery patients. Missed doses occur commonly and are the only identified risk factor for DVT that can be ameliorated by physicians. Efforts to minimize interrupted enoxaparin prophylaxis in patients at risk for DVT should be optimized.