The Initial Impact of Tele-Critical Care on the Surgical Services of a Community Military Hospital.

Introduction: Mortality is reduced in hospitals staffed with intensivists, however, many smaller military hospitals lack intensivist support. Naval Hospital Camp Pendleton (NHCP) is a Military Treatment Facility (MTF) that operates a 6-bed Intensive Care Unit (ICU) north of its referral center, Naval Medical Center San Diego (NMCSD). To address a gap in NHCP on-site intensivist coverage, a comprehensive Tele-Critical Care (TCC) support system was established between NHCP and NMCSD. To examine the initial impact of telemedicine on surgical ICU patients, we compare NHCP surgical ICU admissions before and after TCC implementation. Materials and methods: Patient care by remote intensivist was achieved utilizing video teleconferencing technology, and remote access to electronic medical records. Standardization was promoted by adopting protocols and mandatory intensivist involvement in all ICU admissions. Surgical ICU admissions prior to TCC implementation (pre-TCC) were compared to those following TCC implementation (post-TCC). Results: Of 828 ICU admissions, 21% were surgical. TCC provided coverage during 35% of the intervention period. Comparing pre-TCC and post-TCC periods, there was a significant increase in the percentage of surgical ICU admissions [15.3 % vs 24.6%, p = 0.01] and the average monthly APACHE II score [4.1vs 6.5, p = 0.03]. The total number of surgical admissions per month also increased [3.9 vs 6.3, p = 0.009]. No adverse outcomes were identified. Conclusion: Implementation of TCC was associated with an increase in the scope and complexity of surgical admissions with no adverse outcomes. Surgeons were able to safely expand the surgical services offered requiring perioperative ICU care to patients who previously may have been transferred. Caring for these types of patients not only maintains the operational readiness of deployable caregivers but patient experience is also enhanced by minimizing transfers away from family. Further exploration of TCC on surgical case volume and complexity is warranted.

Risk factors for deep vein thrombosis and pulmonary embolism after traumatic injury: A competing risks analysis.

BACKGROUND: Venous thromboembolism, including deep vein thrombosis (DVT) and pulmonary embolism (PE), is typically reported as a composite measure of the quality of trauma center care. Given that recent data suggesting postinjury DVT and PE are distinct clinical processes, a better understanding may result from analyzing them as independent, competing events. Using competing risks analysis, we evaluated our hypothesis that the risk factors and timing of postinjury DVT and PE are different. METHODS: We examined all adult trauma patients admitted to our Level I trauma center from July 2006 to December 2011 who received at least one surveillance duplex ultrasound of the lower extremities and who were at high risk or greater for DVT. Outcomes included DVT and PE events, and time-to-event from admission. We used competing risks analysis to evaluate risk factors for DVT while accounting for PE as a competing event, and vice versa. RESULTS: Of 2,370 patients, 265 (11.2%) had at least one venous thromboembolism event, 235 DVT only, 19 PE only, 11 DVT and PE. Within 2 days of admission, 38% of DVT cases had occurred compared with 26% of PE. Competing risks modeling of DVT as primary event identified older age, severe injury (Injury Severity Score, ≥ 15), mechanical ventilation longer than 4 days, active cancer, history of DVT or PE, major venous repair, male sex, and prophylactic enoxaparin and prophylactic heparin as associated risk factors. Modeling of PE as the primary event showed younger age, nonsevere injury (Injury Severity Score, < 15), central line placement, and prophylactic heparin as relevant factors. CONCLUSION: The risk factors for PE and DVT after injury were different, suggesting that they are clinically distinct events that merit independent consideration. Many DVT events occurred early despite prophylaxis, bringing into question the preventability of postinjury DVT. We recommend trauma center quality reporting program measures be revised to account for DVT and PE as unique events. LEVEL OF EVIDENCE: Epidemiologic, level III.

The rate of deep vein thrombosis doubles in trauma patients with hypercoagulable thromboelastography.

BACKGROUND: Venous thromboembolism (VTE) in trauma can occur in patients at low risk. Conventional coagulation tests do not predict VTE. Studies investigating thromboelastography (TEG) for VTE risk are conflicting and have not included routine surveillance to detect deep vein thrombosis (DVT). We undertook a prospective study of TEG to evaluate its utility in predicting VTE. METHODS: We conducted a prospective cohort study on all adult trauma patients admitted to our Level I trauma center from 2013 to 2015. TEG was performed immediately on arrival to the trauma bay. Hypercoagulable TEG was defined as reaction time (R) below, angle (α) above, or maximum amplitude (MA) above reference ranges. All patients received mechanical and/or pharmacologic prophylaxis and were followed up for DVT with our ultrasound surveillance protocol. The primary outcome was lower-extremity DVT. After bivariate analysis of variables related to DVT, those with p values of 0.100 or less were included for multivariate logistic regression. RESULTS: A total of 983 patients were evaluated with TEG on admission; of these, 684 (69.6%) received at least one surveillance ultrasound during the index admission. Lower-extremity DVT was diagnosed in 99 (14.5%) patients. Hypercoagulability based on admission TEG occurred in 582 (85.1%) patients. The lower-extremity DVT rate was higher in patients with hypercoagulable TEG than in those without hypercoagulable TEG (15.6% vs. 8%; p = 0.039). Multivariate analysis showed hypercoagulable TEG remained associated with DVT after adjustment for relevant covariates available at admission, with an odds ratio of 2.41 (95% confidence interval, 1.11-5.24; p = 0.026). CONCLUSION: Most trauma patients were hypercoagulable at admission and remained at risk of developing DVT. The rate of DVT doubled in patients with hypercoagulable TEG indices despite prophylaxis. Beyond its current clinical roles, TEG is useful for assessing DVT risk, particularly in patients otherwise perceived to be at low risk. LEVEL OF EVIDENCE: Prognostic study, level II.

Determining the magnitude of surveillance bias in the assessment of lower extremity deep venous thrombosis: A prospective observational study of two centers.

BACKGROUND: Venous thromboembolism (VTE) remains a significant cause of morbidity and mortality in trauma. Controversy exists regarding the use of lower extremity duplex ultrasound screening and surveillance (LEDUS). Advocates cite earlier diagnosis and treatment of deep venous thrombosis (DVT) to prevent clot propagation and pulmonary embolism (PE). Opponents argue that LEDUS identifies more DVT (surveillance bias) but does not reduce the incidence of PE. We sought to determine the magnitude of surveillance bias associated with LEDUS and test the hypothesis that LEDUS does not decrease the incidence of PE after injury. METHODS: We compared data from two Level 1 trauma centers: Scripps Mercy Hospital, which used serial LEDUS, and Christiana Care Health System, which used LEDUS only for symptomatic patients. Beginning in 2013, both centers prospectively collected data on demographics, injury severity, and VTE risk for patients admitted for more than 48 hours. Both centers used mechanical and pharmacologic prophylaxis based on VTE risk assessment. RESULTS: Scripps Mercy treated 772 patients and Christiana Care treated 454 patients with similar injury severity and VTE risk. The incidence of PE was 0.4% at both centers. The odds of a DVT diagnosis were 5.3 times higher (odds ratio, 5.3; 95% confidence interval, 2.5-12.9; p < 0.0001) for patients admitted to Scripps Mercy than for patients admitted to Christiana Care. Of the 80 patients who developed DVT, PE, or both, 99% received prophylaxis before the event. Among those who received pharmacologic prophylaxis, the VTE rates between the two centers were not statistically significantly different (Scripps Mercy, 11% vs. Christiana Care, 3%; p = 0.06). CONCLUSION: The odds of a diagnosis of DVT are increased significantly when a program of LEDUS is used in trauma patients. Neither pharmacologic prophylaxis nor mechanical prophylaxis is completely effective in preventing VTE in trauma patients. VTE should not be considered a "never event" in this cohort. LEVEL OF EVIDENCE: Prognostic/epidemiologic study, level III; therapeutic study, level III.

Venous thromboembolic risk assessment models should not solely guide prophylaxis and surveillance in trauma patients.

BACKGROUND: Venous thromboembolism (VTE) risk assessment models exist to stratify patients at risk for VTE and guide surveillance and prophylaxis. We evaluated the only two models developed specifically for trauma patients: the Trauma Embolic Scoring System (TESS) and the Risk Assessment Profile (RAP). METHODS: Clinical and demographic data on patients admitted from July 2006 to December 2011 who underwent surveillance lower extremity duplex ultrasound were recorded. Patients were excluded if they were missing one or more of the variables required to calculate either TESS or RAP. Patients received prophylaxis according to American College of Chest Physicians guidelines. TESS and RAP scores were calculated retrospectively and compared between patients with VTE and patients without VTE. High risk was defined by the models as TESS score of 7 or greater and RAP score of 5 or greater. RESULTS: A total of 2,868 patients received surveillance lower extremity duplex ultrasound. TESS score was calculated for 2,140 patients; 215 developed VTE, 110 (51%) of whom had TESS score less than 7. The sensitivity and specificity at a cutoff point of 7 were 49% and 72%, respectively. RAP score was calculated for 1,505 patients; 152 developed VTE, 26 (17%) of whom had RAP score of less than 5. The sensitivity and specificity at a cutoff point of 5 were 83% and 37%, respectively. The area under the receiver operating characteristic curve for each model was 0.66. CONCLUSION: A clinically significant number of patients who developed VTE were classified as low risk by both TESS and RAP. The indications for VTE surveillance and chemoprophylaxis should not be based exclusively on these scores. These results suggest that additional variables should be sought to improve risk assessment for VTE following trauma. LEVEL OF EVIDENCE: Care management study, level III.

Heparin versus enoxaparin for prevention of venous thromboembolism after trauma: A randomized noninferiority trial.

BACKGROUND: Research comparing enoxaparin with unfractionated heparin (UFH) given every 12 hours for venous thromboembolism (VTE) prophylaxis after trauma overlooks original recommendations that UFH be given every 8 hours. We conducted a prospective, randomized, noninferiority trial comparing UFH every 8 hours and standard enoxaparin every 12 hours. We hypothesized that the incidence of VTE in trauma patients receiving UFH every 8 hours would be no more than 10% higher than that in patients receiving enoxaparin every 12 hours. METHODS: Trauma patients who met criteria for VTE prophylaxis at a Level I trauma center were randomly assigned to 5,000-U UFH every 8 hours or 30-mg enoxaparin every 12 hours between November 2012 and September 2014. Surveillance duplex ultrasound was performed twice weekly on intensive care unit patients and weekly on ward patients. Primary end points were deep vein thrombosis diagnosed by duplex ultrasound and pulmonary embolism diagnosed by computed tomography angiography. RESULTS: Of 495 randomized patients, 220 received UFH and 216 received enoxaparin for analysis. Overall, 105 in the UFH group and 103 in the enoxaparin group underwent VTE surveillance or diagnostic testing. In the analysis of randomized patients who received treatment, UFH was noninferior compared with enoxaparin (absolute VTE risk difference, 3.1%; 95% confidence interval, -1.6% to 7.7%; p = 0.196); however, in the screening ultrasound group, the noninferiority of UFH was inconclusive (absolute VTE risk difference, 6.5%; 95% confidence interval, -2.9% to 15.8%; p = 0.179). The two treatments did not differ with regard to adverse events. The pharmaceutical cost for the regimen of UFH ($2,809) was nearly 20-fold lower than that for enoxaparin ($54,138). CONCLUSION: A regimen of UFH every 8 hours may be noninferior to enoxaparin every 12 hours for the prevention of VTE following trauma. Given UFH's cost advantage, the use of UFH for VTE prophylaxis may offer greater value. LEVEL OF EVIDENCE: Therapeutic/care management study, level II.

Does resuscitation with plasma increase the risk of venous thromboembolism?

BACKGROUND: Resuscitation with blood products improves survival in patients with traumatic hemorrhage. However, the risk of venous thromboembolic (VTE) complications associated with fresh frozen plasma (FFP) resuscitation is unknown. We hypothesized that a higher ratio of FFP to packed red blood cells (PRBCs) given during acute resuscitation increases the risk of VTE independent of severity of injury and shock. METHODS: The records of patients admitted from April 2007 to December 2011 who had surveillance lower extremity duplex ultrasounds were retrospectively reviewed. Patients who received at least 1 U of PRBCs within 24 hours of admission were included. Patients who died without VTE were excluded. The relationship between FFP and VTE was evaluated using logistic regression. RESULTS: A total of 381 patients met inclusion criteria, of whom 77 (20.2%) developed VTE. In patients who required less than 4 U of PRBCs, increasing units of FFP were associated with an increasing risk for VTE, with each unit of FFP having an adjusted odds ratio of 1.27 (95% confidence interval, 1.04-1.54, p = 0.015). Conversely, in patients who required four or greater units of PRBCs, FFP in equal or greater ratios than PRBCs was not associated with VTE. CONCLUSION: Each unit of FFP increased VTE risk by 25% in patients who required less than 4 U of PRBCs. In patients who required 4 U or greater PRBCs, FFP administration conferred no increased risk of VTE. This suggests that FFP should be used cautiously when early hemodynamic stability can be achieved with less than 4 U of PRBCs. LEVEL OF EVIDENCE: Care management study, level III.

Below-knee deep vein thrombosis: an opportunity to prevent pulmonary embolism?

BACKGROUND: The prevention of venous thromboembolic disease following trauma is a priority. In contrast to above-knee deep vein thrombosis (AKDVT), the management of below-knee deep vein thrombosis (BKDVT) is controversial because the risk of pulmonary embolism (PE) has not been firmly established. We hypothesized that BKDVT and AKDVT have an equivalent risk for PE in trauma patients. METHODS: We identified patients from July 2006 to December 2011 with BKDVT and/or AKDVT diagnosed by lower extremity duplex ultrasound (LEDU) and patients with PE diagnosed by computed tomography angiogram. Time of DVT onset, progression or regression, and time of PE were assessed. The BKDVT and AKDVT patient groups were defined by the location of DVT on initial LEDU. The use of therapeutic anticoagulation and inferior vena cava filter (IVCF) were compared between the BKDVT and AKDVT groups. RESULTS: Of 11,330 patients evaluated during the study period, 2,881 (25.4%) underwent surveillance LEDU, and 251 (8.7%) of these patients had DVT alone or associated with PE. BKDVT progressed to AKDVT and/or PE in 21 patients (12.9%). PE rates were 6.1% and 1.1% in the BKDVT and AKDVT groups, respectively (p = 0.1). There was a higher rate of therapeutic anticoagulation and/or IVCF in the AKDVT group than in the BKDVT group (86% vs. 24%, p < 0.0001). CONCLUSION: In our study population, BKDVT was associated with a higher rate of PE compared with AKDVT, which was likely secondary to the treatment of AKDVT. Because BKDVT progressed to AKDVT or PE in 1 of 8 patients, BKDVT should not be ignored in trauma patients. Aggressive chemical prophylaxis and perhaps therapeutic anticoagulation or IVCF should be considered in patients with BKDVT. Further investigation is warranted to confirm these conclusions. LEVEL OF EVIDENCE: Therapeutic study, level IV.

Pulmonary embolism without deep venous thrombosis: De novo or missed deep venous thrombosis?

BACKGROUND: Pulmonary embolus (PE) is thought to arise from a deep venous thrombosis (DVT). Recent data suggest that PE can present without DVT, inferring that PE can originate de novo (DNPE). We examined the relationship between DVT and PE in trauma patients screened for DVT with duplex sonography (DS). We sought to validate the incidence of PE without evidence of DVT and to examine the clinical significance of this entity. METHODS: We reviewed the medical records of all trauma patients from July 2006 to December 2011 with PE who also had serial surveillance DS (groin to ankle). Demographics, severity of injury, interventions, signs and symptoms of PE, as well as chest computerized tomography findings were collected. Patients with no DS evidence of DVT either before or within 48 hours of PE diagnosis (DNPE) were compared with those with DVT (PE + DVT). RESULTS: Of 11,330 patients evaluated by the trauma service, 2,881 patients received at least one DS. PE occurred in 31 of these patients (1.08%): 19 (61%) were DNPE, and 12 (39%) were PE + DVT. Compared with patients with PE + DVT, patients with DNPE were significantly younger and had more rib fractures, pulmonary contusions, infections, pulmonary symptoms, and peripherally located PEs on computerized tomography. CONCLUSION: This is the first report of the clinical course of DNPE without embolic origin in a population with comprehensive duplex surveillance. In our series, DNPE seems to be more prevalent after trauma, to be clinically distinct from PE following DVT, and to likely represent a local response to injury or inflammation; however, further research is warranted to fully understand the pathophysiology of DNPE. LEVEL OF EVIDENCE: Care management study, level III.

Isolated traumatic brain injury and venous thromboembolism.

BACKGROUND: Traumatic brain injury (TBI) is considered an independent risk factor of venous thromboembolism (VTE). However, the role of TBI severity in VTE risk has not been determined. We hypothesized that increased severity of brain injury in patients with isolated TBI (iTBI) is associated with an increased incidence of VTE. METHODS: The records of patients admitted from June 2006 to December 2011 were reviewed for injury data, VTE risk factors, results of lower extremity surveillance ultrasound, and severity of TBI. Patients were identified by DRG International Classification of Diseases-9th Rev. codes for TBI, and only those with a nonhead Abbreviated Injury Scale (AIS) score of 1 or lower, indicating minimal associated injury, were included. The association of iTBI and VTE was determined using a case-control design. Among iTBI patients, those diagnosed with VTE (cases) were matched for age, sex, and admission year to those without VTE (controls). Data were analyzed using conditional logistic regression. RESULTS: There were 345 iTBI patients: 41 cases (12%) and 304 controls (88%). A total of 151 controls could not be matched to an appropriate case and were excluded. Of the remaining 153 controls, 1 to 16 controls were matched to each of the 41 VTE cases. Compared with the controls, the cases had a higher mean head-AIS score (4.4 vs. 3.9, p = 0.001) and overall Injury Severity Score (20.4 vs. 16.8, p = 0.001). Following adjustment for all factors found to be associated with VTE (ventilator days, central line placement, operative time > 2 hours, chemoprophylaxis, history of VTE, and history of cancer), the cases were significantly more likely to have a greater head injury severity (head-AIS score ≥ 5; odds ratio, 5.25; 95% confidence interval, 1.59-17.30; p = 0.006). CONCLUSION: The incidence of VTE in iTBI patients was significantly associated with the severity of TBI. VTE surveillance protocols may be warranted in these high-risk patients, as early detection of VTE could guide subsequent therapy. LEVEL OF EVIDENCE: Epidemiologic/prognostic study, level III.