The Variation of Withdrawal of Life Sustaining Therapy in Older Adults With Traumatic Brain Injury.

INTRODUCTION: The decision to withdraw life sustaining treatment (WDLST) in older adults with traumatic brain injury is subject to wide variability leading to nonbeneficial interventions and unnecessary use of hospital resources. We hypothesized that patient and hospital factors are associated with WDLST and WDLST timing. METHODS: All traumatic brain injury patients ≥65 with Glasgow coma scores (GCS) of 4-11 from 2018 to 2019 at level I and II centers were selected from the National Trauma Data Bank. Patients with head abbreviated injury scores 5-6 or death within 24 h were excluded. Bayesian additive regression tree analysis was performed to identify the cumulative incidence function (CIF) and the relative risks (RR) over time for withdrawal of care, discharge to hospice (DH), and death. Death alone (no WDLST or DH) served as the comparator group for all analyses. A subanalysis of the composite outcome WDLST/DH (defined as end-of-life-care), with death (no WDLST or DH) as a comparator cohort was performed. RESULTS: We included 2126 patients, of whom 1957 (57%) underwent WDLST, 402 (19%) died, and 469 (22%) were DH. 60% of patients were male, and the mean age was 80 y. The majority of patients were injured by fall (76%, n = 1644). Patients who were DH were more often female (51% DH versus 39% WDLST), had a past medical history of dementia (45% DH versus 18% WDLST), and had lower admission injury severity score (14 DH versus 18.6 WDLST) (P < 0.001). Compared to those who DH, those who underwent WDLST had a lower GCS (9.8 versus 8.4, P < 0.001). CIF of WDSLT and DH increased with age, stabilizing by day 3. At day 3, patients ≥90 y had an increased RR of DH compared to WDLST (RR 2.5 versus 1.4). As GCS increased, CIF and RR of WDLST decreased, while CIF and RR of DH increased (RR on day 3 for GCS 12: WDLST 0.42 versus DH 1.31).Patients at nonprofit institutions were more likely to undergo WDLST (RR 1.15) compared to DH (0.68). Compared to patients of White race, patients of Black race had a lower RR of WDLST at all timepoints. CONCLUSIONS: Patient and hospital factors influence the practice of end-of-life-care (WDLST, DH, and death), highlighting the need to better understand variability to target palliative care interventions and standardize care across populations and trauma centers.

Shock associated with endothelial dysfunction in omental microvessels.

BACKGROUND: Impaired microvascular function leads to a poor outcome in a variety of medical conditions. Our aim was to determine whether vasodilator responses to acetylcholine (Ach) are impaired in human omental arterioles from patients with severe trauma. MATERIALS AND METHODS: Patients with massive blood loss and severe shock requiring damage control procedures were included. Tissues were collected at the first (FEL) and the second explorative laparotomy (SEL). Control tissues were collected from nontrauma patients. Freshly isolated 50-200-µm-diameter omental arterioles were analysed using videomicroscopy. Dihydroethidine and DCF-DA fluorescence were used to assess reactive oxygen species (ROS) production. MnTBAP was used to determine the contribution of excess vascular superoxide contribution to endothelial dysfunction. RESULTS: After constriction (30-50%) with endothelin-1, dilation to graded doses of Ach (10-9 -10-4 M) was greater in control vessels compared to FEL and SEL (max dilation at 10-4 M (MD) = 25 ± 3%, n = 8; and 59 ± 8%, n = 8, respectively, and controls MD = 93 ± 10%, n = 6, P < 0·05). Fluorescence imaging of ROS production showed significant increases in superoxide (225·46 ± 12·86; 215·77 ± 10·75 vs. 133·75 ± 7·26, arbitrary units; P < 0·05) and peroxide-related ROS (240·8 ± 20·42; 234·59 ± 28·86, vs. 150·78 ± 15·65, arbitrary units; P < 0·05), in FEL and SEL microvessels compared to control, respectively. FEL pretreated with MnTBAP demonstrated significant improvement in Ach-induced vasodilation (25·5 ± 3·0% vs. 79·5 ± 8·2%; P < 0·05). CONCLUSIONS: Severe shock associated with microvascular endothelial dysfunction enhances production of ROS in human omental tissues. The altered flow regulation may contribute to a mismatch between local blood supply and demand, exacerbating abnormal tissue perfusion and function.

Analysis of Injury Metrics From Experimental Cardiac Injuries From Behind Armor Blunt Trauma Using Live Swine Tests: A Pilot Study.

INTRODUCTION: Warfighters are issued hard body armor designed to defeat ballistic projectiles. The resulting backface deformation can injure different thoracoabdominal organs. Developed over decades ago, the behind armor blunt impact criterion of maximum 44 mm depth in clay continues to be used independent of armor type or impact location on the thoracoabdominal region covered by the armor. Because thoracoabdominal components have different energy absorption capabilities, their mode of failures and mechanical properties are different. These considerations underscore the lack of effectiveness of using the single standard to cover all thoracoabdominal components to represent the same level of injury risk. The objective of this pilot study is to conduct cardiac impact tests with a live animal model and analyze biomechanical injury candidate metrics for behind armor blunt trauma applications. MATERIALS AND METHODS: Live swine tests were conducted after obtaining approvals from the U.S. DoD. Trachea tubes. An intravenous line were introduced into the swine before administering anesthesia. Pressure transducers were inserted into lungs and aorta. An indenter simulating backface deformation profiles produced by body armor from military-relevant ballistics to human cadavers delivered impact to the heart region. The approved test protocol included 6-hour monitoring and necropsies. Indenter accelerometer signals were processed to compute the velocity and deflection, and their peak magnitudes were obtained. The deflection-time signal was normalized with respect to chest depth along the impact axis. The peak magnitude of the viscous criterion, kinetic energy, force, momentum and stiffness were obtained. RESULTS: Out of the 8 specimens, 2 were sham controls. The mean total body mass and soft tissue thickness at the impact site were 81.1 ± 4.1 kg and 3.8 ± 1.1 cm. The peak velocities ranged from 30 to 59 m/s, normalized deflections ranged from 15 to 21%, and energies ranged from 105 to 407 J. The range in momentum and stiffness were 7.0 to 13.9 kg-m/s and 22.3 to 79.9 N/m. The maximum forces and impulse data ranged from 2.9 to 11.7 kN and 1.9 to 5.8 N-s. The peak viscous criterion ranged from 2.0 to 5.3 m/s. One animal did not sustain any injuries, 2 had cardiac injuries, and others had lung and skeletal injuries. CONCLUSIONS: The present study applied blunt impact loads to the live swine cardiac region and determined potential candidate injury metrics for characterization. The sample size of 6 swine produced injuries ranging from none to pure skeletal to pure organ trauma. The viscous criterion metric associated with the response of the animal demonstrated a differing pattern than other variables with increasing velocity. These findings demonstrate that our live animal experimental design can be effectively used with testing additional samples to develop behind armor blunt injury criteria for cardiac trauma in the form of risk curves. Injury criteria obtained for cardiac trauma can be used to enhance the effectiveness of the body armor, reduce morbidity and mortality, and improve warfighter readiness in combat operations.

Matched-pair hybrid test paradigm for behind armor blunt trauma using an experimental animal model.

Background: The current behind armor blunt trauma (BABT) injury criterion uses a single penetration limit of 44 mm in Roma Plastilina clay and is not specific to thoracoabdominal regions. However, different regions in the human body have different injury tolerances. This manuscript presents a matched-pair hybrid test paradigm with different experimental models and candidate metrics to develop regional human injury criteria. Methods: Live and cadaver swine were used as matched pair experimental models. An impactor simulating backface deformation profiles produced by body armor from military-relevant ballistics was used to deliver BABT loading to liver and lung regions in cadaver and live swine. Impact loading was characterized using peak accelerations and energy. For live swine, physiological parameters were monitored for 6 hours, animals were euthanized, and a detailed necropsy was done to identify injuries to skeletal structures, organs and soft tissues. A similar process was used to identify injuries to the cadaver swine for targeted thoracoabdominal regions. Results: Two cadavers and one live swine were subjected to BABT impacts to the liver. One cadaver and one live swine were subjected to BABT impacts to the left lung. Injuries to both regions were similar at similar energies between the cadaver and live models. Conclusions: Swine is an established animal for thoracoabdominal impact studies in automotive standards, although at lower insult levels. Similarities in BABT responses between cadaver and live swine allow for extending testing protocols to human cadavers and for the development of scaling relationships between animal and human cadavers, acting as a hybrid protocol between species and live and cadaver models. Injury tolerances and injury risk curves from live animals can be converted to human tolerances via structural scaling using these outcomes. The present experimental paradigm can be used to develop region-based BABT injury criteria, which are not currently available.

Undetected penetrating bladder injuries presenting as a spontaneously expulsed bullet during voiding: a rare entity and review of the literature.

BACKGROUND: Patients presenting with a penetrating missile lodged in the pelvis are at risk for having a urinary tract injury. Once in the bladder, the missile can become impacted in the urethra, causing retention that requires extraction. Rarely, the missile can be expulsed spontaneously through the urethra. OBJECTIVES: To describe the world literature regarding undetected penetrating bladder injuries presenting as spontaneously voided bullets and to contribute an additional case to the literature. CASE REPORT: We present a case report of a 37-year-old man who sustained a gunshot wound to the right buttock, with an undetected urinary system injury and subsequent spontaneous voiding of a bullet. CONCLUSION: There have been <10 cases reported in the literature of spontaneously expulsed bullets from the urethra, all of which were undetected injuries on initial presentation. Physicians should be aware of the potential for undetected urinary tract injuries in patients with penetrating missiles to the pelvis and understand the appropriate evaluation and management strategies for these injuries.

Optimizing discharge opioid prescribing in trauma patients: A quasi-experimental study.

BACKGROUND: Patients prescribed higher opioid dosages are at increased risk of overdose and death without added pain reduction. Increases in opioid prescribing continue to fuel the epidemic. We hypothesized a comprehensive guideline to standardize opioid prescribing would decrease postdischarge dosages for patients experiencing trauma without requiring additional refills. METHODS: This quasiexperimental study compared opioid prescribing by trauma providers before and after the implementation of a departmental guideline on April 1, 2019, aimed at aligning opioid prescription patterns with Centers for Disease Control and Prevention recommendations. Patients prescribed opioids before implementation were the control group, whereas patients prescribed opioids after were the intervention group. The primary outcome was the proportion of patients receiving ≥50 morphine milligram equivalents per day. RESULTS: We identified 293 and 280 patients experiencing trauma in the control and intervention groups, respectively. There were no differences between the groups' Injury Severity Score (P = .69) or the frequency of having a procedure performed (P = .80). Total morphine milligram equivalents and maximum morphine milligram equivalents per day were 16% and 25% lower, respectively, in the intervention group compared with the control group (P < .001). The proportion of trauma patients prescribed ≥50 morphine milligram equivalents per day at discharge decreased from 57% to 18% after implementation (P < .001). The proportion of trauma patients prescribed ≥90 morphine milligram equivalents per day also decreased, from 37% to 14% (P < .001). There was no significant increase in the frequency of refill requests (P = .105) or refill prescriptions (P = .099) after discharge. CONCLUSION: A departmental guideline aimed at optimizing opioid prescription patterns successfully lowers the amount of morphine milligram equivalents prescribed to trauma patients and improves compliance with Centers for Disease Control and Prevention recommendations.

A Novel Paradigm to Develop Regional Thoracoabdominal Criteria for Behind Armor Blunt Trauma Based on Original Data.

INTRODUCTION: For behind armor blunt trauma (BABT), recent prominent BABT standards for chest plate define a maximum deformation distance of 44 mm in clay. It was developed for soft body armor applications with limited animal, gelatin, and clay tests. The legacy criterion does not account for differing regional thoracoabdominal tolerances to behind armor-induced injury. This study examines the rationale and approaches used in the legacy BABT clay criterion and presents a novel paradigm to develop thoracoabdominal regional injury risk curves. MATERIALS AND METHODS: A review of the original military and law enforcement studies using animals, surrogates, and body armor materials was conducted, and a reanalysis of data was performed. A multiparameter model analysis describes survival-lethality responses using impactor/projectile (mass, diameter, and impact velocity) and specimen (weight and tissue thickness) variables. Binary regression risk curves with ±95% confidence intervals (CIs) and peak deformations from simulant tests are presented. RESULTS: Injury risk curves from 74 goat thorax tests showed that peak deflections of 44.7 mm (±95% CI: 17.6 to 55.4 mm) and 49.9 mm (±95% CI: 24.7 to 60.4 mm) were associated with the 10% and 15% probability of lethal outcomes. 20% gelatin and Roma Plastilina #1 clay were stiffer than goat. The clay was stiffer than 20% gelatin. Penetration diameters showed greater variations (on a test-by-test basis, difference 36-53%) than penetration depths (0-12%) across a range of projectiles and velocities. CONCLUSIONS: While the original authors stressed limitations and the importance of additional tests for refining the 44 mm recommendation, they were not pursued. As live swine tests are effective in developing injury criteria and the responses of different areas of the thoracoabdominal regions are different because of anatomy, structure, and function, a new set of swine and human cadaver tests are necessary to develop scaling relationships. Live swine tests are needed to develop incapacitation/lethal injury risk functions; using scaling relationships, human injury criteria can be developed.

Trauma surgeon-performed peripheral arterial repairs are associated with equivalent outcomes when compared with vascular surgeons.

BACKGROUND: Civilian extremity trauma with vascular injury carries a significant risk of morbidity, limb loss, and mortality. We aim to describe the trends in extremity vascular injury repair and compare outcomes between trauma and vascular surgeons. METHODS: We performed a single-center retrospective review of patients 18 years or older with extremity vascular injury requiring surgical intervention between January 2009 and December 2019. Demographics, injury characteristics, operative course, and hospital course were analyzed. Descriptive statistics were used to examine management trends, and outcomes were compared for arterial repairs. Multivariate regression was used to evaluate surgeon specialty as a predictor of complications, readmission, vascular outcomes, and mortality. RESULTS: A total of 231 patients met our inclusion criteria; 80% were male with a median age of 29 years. The femoral vessels were most commonly injured (39.4%), followed by the popliteal vessels (26.8%). Trauma surgeons performed the majority of femoral artery repairs (82%), while vascular surgeons repaired the majority of popliteal artery injuries (84%). Both had a similar share of brachial artery repairs (36% vs. 39%, respectively). There were no differences in complications, readmission, vascular outcomes, and mortality. Median time from arrival to operating room was significantly shorter for trauma surgeons. There was a significant downward trend between 2009 and 2017 in the proportion of total and femoral vascular procedures performed by trauma surgeons. On multivariate regression, surgical specialty was not a significant predictor of need for vascular reintervention, prophylactic or delayed fasciotomies, postoperative complications, or readmissions. CONCLUSION: Traumas surgeons arrived quicker to the operating and had no difference in short-term clinical outcomes of brachial and femoral artery repairs compared with patients treated by vascular surgeons. Over the last decade, there has been a significant decline in the number of open vascular repairs done by trauma surgeons. LEVEL OF EVIDENCE: Therapeutic/Care Management, Level IV.

Time-course and mechanisms of restored vascular relaxation by reduced salt intake and angiotensin II infusion in rats fed a high-salt diet.

OBJECTIVE: This study determined the mechanisms and time-course of recovery of vascular relaxation in middle cerebral arteries (MCAs) of salt-fed Sprague-Dawley rats returned to a low-salt (LS) diet (0.4% NaCl) or infused with low-dose angiotensin II (ANG II). METHODS: Rats were fed a high-salt (HS) diet (4% NaCl) for 3 days or 4 weeks before returning to an LS diet for various periods. Other rats fed a HS diet (HS+ANG II) received a chronic (3 days) intravenous (i.v.) infusion of a low dose of ANG II (5 ng kg(-1) min(-1)) to prevent salt-induced ANG II suppression. RESULTS: The HS diet eliminated the increase in cerebral blood flow in response to acetylcholine (ACh) infusion and the relaxation of MCA in response to ACh, iloprost, cholera toxin, and reduced PO2. Recovery of vascular relaxation was slow, requiring at least 2 weeks of the LS diet, regardless of the duration of exposure to a HS diet. Hypoxic dilation was mediated by cyclo-oxygenase metabolites and ACh-induced dilation was mediated via nitric oxide in LS rats and in HS rats returned to the LS diet or receiving ANG II infusion. CONCLUSIONS: Returning to a LS diet for 2 weeks or chronic 3-day ANG II infusion restores the mechanisms that normally mediate cerebral vascular relaxation.

Ketamine infusion for pain control in elderly patients with multiple rib fractures: Results of a randomized controlled trial.

BACKGROUND: Rib fractures are associated with increased mortality, particularly in the elderly. While opiate-based pain regimens remain the cornerstone of rib fracture management, issues related to opioids have driven research into alternative analgesics. Adjunctive ketamine use in lieu of opioids continues to increase but little evidence exists to support its efficacy or safety within the elderly trauma population. METHODS: A prospective, randomized, double-blind placebo-controlled trial of elderly patients (age, ≥65 years) with three or more rib fractures admitted to a Level I trauma center was conducted. Exclusion criteria included Glasgow Coma Scale score less than 14, and chronic opiate use. Groups were randomized to either low-dose ketamine (LDK) at 2 µg·kg·min or an equivalent rate of 0.9% normal saline. The primary outcome was reduction in numeric pain scores (NPS). Secondary outcomes included oral morphine equivalent (OME) utilization, epidural rates, pulmonary complications, and adverse events. RESULTS: Thirty (50.8%) of 59 were randomized to the experimental arm. Groups were similar in makeup. Low-dose ketamine failed to reduce 24-hour NPS or OME totals. Subgroup analysis of 24 patients with Injury Severity Score greater than 15 demonstrated that LDK was associated with a reduction in OME utilization the first 24-hours (25.6 mg vs. 42.6 mg, p = 0.04) but at no other time points. No difference in other secondary outcomes or adverse events was noted. CONCLUSION: Low-dose ketamine failed to affect NPS or OME within the overall cohort, but a decrease in OME was observed in those with an Injury Severity Score greater than 15. Additional studies are necessary to confirm whether LDK benefits severely injured elderly patients. LEVEL OF EVIDENCE: Therapeutic, level I.

Ketamine infusion for pain control in adult patients with multiple rib fractures: Results of a randomized control trial.

BACKGROUND: Rib fractures occur in up to 40% of trauma patients and are associated with increased mortality. Opiate-based pain regimens remain the cornerstone of rib fracture management; however, concerns around opioids have fostered interest in alternative analgesics. Ketamine is currently being used in lieu of opioids, but little evidence exists supporting its use within the trauma population. METHODS: A prospective, randomized, double-blind placebo-controlled trial of adult patients with three or more rib fractures admitted to a Level I trauma center was conducted. Exclusion criteria included age older than 64 years, Glasgow Coma Scale score less than 13, and chronic opiate use. The experimental arm received low-dose ketamine (LDK) at 2.5 µg·kg·min while the placebo cohort received an equivalent rate of 0.9% normal saline. All infusions were continued for 48 hours. The primary outcome was reduction in numeric pain score (NPS) during the first 24 hours. Secondary outcomes studied included oral morphine equivalent (OME) utilization, length of stay, epidural rates, pulmonary complications, and adverse events. RESULTS: Forty-five (49%) of 91 patients were randomized to the experimental arm. Both groups were similar in makeup. Overall, 74.7% were male, had a median age of 49 years, and an Injury Severity Score (ISS) of 14. Low-dose ketamine was not associated with a significant reduction in 24-hour NPS or OME totals. Subgroup analysis of 45 severely injured patients (ISS, >15) demonstrated that LDK was associated with a significant reduction in OME utilization during the first 24 hours (35.7 vs. 68, p = 0.03), 24 hours to 48 hours (64.2 vs. 96, p = 0.03), and overall (152.1 vs. 198, p = 0.048). No difference in other secondary outcomes or adverse events was noted. CONCLUSION: Low-dose ketamine failed to decrease NPS or OME within the overall cohort, but a decrease in OME was observed among patients with an ISS greater than 15. Confirmatory studies are necessary to determine if LDK is a useful adjunct among severely injured patients. LEVEL OF EVIDENCE: Therapeutic study, level II.

Intermittent intravenous pantoprazole and continuous cimetidine infusion: effect on gastric pH control in critically ill patients at risk of developing stress-related mucosal disease.

BACKGROUND: This study aimed to assess intermittent intravenous (IV) pantoprazole for control of gastric acid and the possible prevention of upper gastrointestinal (UGI) bleeding in intensive care units (ICU) patients. METHODS: This was a multicenter, randomized, open-label, dose-ranging pilot study of IV pantoprazole (40 mg q24 hour; 40 mg q12 hour; 80 mg q24 hour; 80 mg q12 hour; 80 mg q8 hour) or continuously infused cimetidine (300 mg bolus; 50 mg/h) in patients at risk for UGI bleeding. The primary endpoint was percent time gastric pH >/=4.0. UGI bleeding and pneumonia were measured as secondary endpoints. RESULTS: Two hundred two ICU patients were randomized. Gastric pH was well controlled by all treatments. Gastric pH control improved from day 1 to day 2 in all pantoprazole groups, whereas there was decreased pH control in the cimetidine group. There were no cases of protocol defined UGI bleeding in any treatment group. Adverse event frequency and pneumonia incidence were similar between pantoprazole and cimetidine treated patients. CONCLUSIONS: This pilot study indicates that intermittent IV pantoprazole effectively controls gastric pH and may protect against UGI bleeding in high risk ICU patients without the development of tolerance.

Clinical significance of computed tomography contrast extravasation in blunt trauma patients with a pelvic fracture.

INTRODUCTION: Blunt pelvic fractures can be associated with major pelvic bleeding. The significance of contrast extravasation (CE) on computed tomography (CT) is debated. We sought to update our experience with CE on CT scan for the years 2009-2014 to determine the accuracy of CE in predicting the need for angioembolization. METHODS: This is a retrospective review of the trauma registry and our electronic medical record from a Level I trauma center. Patients seen from July 1, 2009, to September 7, 2014, with blunt pelvic fractures and contrast-enhanced CT were included. Standard demographic, clinical, and injury data were obtained. Patient records were queried for CE, performance of angiography, and angioembolization. Positive patients were those where CE was associated with active bleeding requiring angioembolization. All other patients were considered negative. RESULTS: There were 497 patients during the study time period with blunt pelvic fracture meeting inclusion criteria, and 75 patients (15%) had CE. Of those patients with CE, 30 patients (40%) underwent angiography, and 17 patients (23%) required angioembolization. The sensitivity, specificity, positive predictive value, and negative predictive value of CE on CT were 100%, 87.9%, 22.7%, and 100%, respectively. Two patients without CE underwent angiography but did not undergo embolization. Patients with CE had higher mortality (13 vs. 6%, p < 0.05) despite not having higher ISS scores. CONCLUSIONS: This study reinforces that CE on CT pelvis with blunt trauma is common, but many patients will not require angioembolization. The negative predictive value of 100% should be reassuring to trauma surgeons such that if a modern CT scanner is used, and there is no CE seen on CT, then the pelvis will not be a source of hemorrhagic shock. All of these findings are likely due to both increased comfort with observing CEs and the increased sensitivity of modern CT scanners. LEVEL OF EVIDENCE: Therapeutic/care management study, level IV.

Effective retention of primary survey skills by medical students after participation in an expanded Trauma Evaluation and Management course.

BACKGROUND: The Trauma Evaluation and Management (TEAM) module orients medical students to the initial assessment of an injured patient. At the Medical College of Wisconsin, a course based on expanded TEAM (eTEAM) was developed for junior medical students. This study determined whether eTEAM improved the ability to perform and retain primary survey skills. METHODS: Objective Structured Clinical Examination methodology was used to compare 2 groups of senior medical students 1 year after receiving either a 2-hour lecture or eTEAM. RESULTS: Students receiving eTEAM performed the primary survey much better than those receiving lecture alone. The overall Objective Structured Clinical Examination scores did not differ between groups. CONCLUSIONS: Medical students participating in eTEAM retained the ability to perform a primary survey in proper sequence 1 year later better than students receiving the information in lecture format only.

Rib fracture stabilization in patients sustaining blunt chest injury.

Conservative management for the majority of patients with severe chest injuries has produced a reduction in mortality, complications, and hospital length of stay. More recently, operative stabilization of rib fractures has been used with the implication of improved outcome. We assessed the impact of operative rib fracture stabilization on outcome among trauma patients. A matched case-control study of patients undergoing operative rib fracture stabilization was performed. Thirty patients undergoing rib stabilization were matched with 30 controls. Length of intensive care unit (controls, 14.1 +/- 2.7 vs cases, 12.1 +/- 1.2, P = 0.51) and total hospital (controls, 21.1 +/- 3.9 vs cases, 18.8 +/- 1.8, P = 0.59) stay were similar for both groups. There was a trend toward fewer total ventilator days for operative patients (6.5 +/- 1.3 days vs 11.2 +/- 2.6 days, P = 0.12). Ventilator days for operative patients from the time of stabilization was 2.9 +/- 0.6 days compared with 9.4 +/- 2.7 days in controls (P = 0.02). Rib fracture fixation may reduce ventilator requirements in trauma patients with severe thoracic injuries. Long-term functional outcomes need to be assessed to ascertain the impact of this procedure.

The value of process measures in evaluating an evidence-based guideline.

BACKGROUND: Linking the process of evidence-based guidelines to outcomes is difficult. We hypothesized that the process of implementing an evidence-based clinical guideline for blunt splenic trauma would reduce resource consumption and improve outcome. METHODS: Time periods were divided into period 1 (7/1/96-6/30/99) and period 2 (7/1/99-6/30/01). On 7/1/99 our American College of Surgeons-verified level I trauma center instituted an evidence-based approach for managing splenic trauma incorporating hemodynamic normality as the process measure triggering clinical decisions. Outcomes included the number of hemodynamically normal patients treated without operation, patient death, length of stay, and cost. RESULTS: Two hundred thirty-one patients had blunt splenic injury; 115 patients were seen during period 1 and 116 during period 2. Hemodynamically normal patients undergoing splenectomy decreased during period 2 (P<.05). Median length of stay was 8 days in period 1 and 6 days in period 2 (P<.03). Cost per patient was $34,972 US dollars in period 1 and $24,037 US dollars in period 2 (P<.03). The mortality rate was unchanged. CONCLUSIONS: Compliance with evidence-based data in the management of blunt splenic injury improved rates of nonoperative management, decreased hospital days, and did not change mortality rates. An evidence-based clinical guideline evaluated with process measures can reduce resource use and improve outcome in a trauma program.

Optimizing drug therapy in the surgical intensive care unit.

This article provides a review of commonly prescribed medications in the surgical ICU, focusing on sedatives, antipsychotics, neuromuscular blocking agents, cardiovascular agents, anticoagulants, and antibiotics. A brief overview of pharmacology is followed by practical considerations to aid prescribers in selecting the best therapy within a given category of drugs to optimize patient outcomes.

Mechanisms underlying increased reactivity of pulmonary arteries contralateral to a localized high-flow anastomosis.

OBJECTIVES: Our model of a systemic-pulmonary shunt exhibits enhanced reactivity of pulmonary arteries contralateral to a localized shunt between the left lower lobe pulmonary artery and aorta relative to those of ipsilateral or control pulmonary arteries 48 hours after anastomosis. We examined the contribution of nitric oxide, cyclooxygenase, lipoxygenase, or cytochrome P450 production to mediating this enhanced reactivity. METHODS: We created a surgical end-to-side anastomosis of the left lower lobe pulmonary artery to the aorta. Forty-eight hours later, we tested tension of pulmonary artery rings from the right and left lower lobes for contraction to the thromboxane mimetic U46619 in the presence of vehicle or inhibitors of nitric oxide synthase, cyclooxygenase, cytochrome P450, or lipoxygenase. Western blots of pulmonary artery homogenates were probed for endothelial nitric oxide synthase or isoforms metabolizing arachidonic acid. Eicosanoid products from intact pulmonary artery rings were detected using labeled arachidonic acid and high-performance liquid chromatography separation. RESULTS: Enhanced reactivity of unshunted right pulmonary arteries over that of left pulmonary arteries from high-flow hosts was not eliminated by inhibitors of nitric oxide synthase, cyclooxygenase, cytochrome P450. Treatment with 2 different lipoxygenase inhibitors, nordihydroguaiaretic acid and cinnamyl-3,4-dihydroxy-α-cyanocinnamate, closed the difference in contractility of shunted and unshunted pulmonary arteries. Pulmonary arteries contralateral to shunts metabolized arachidonic acid to 12-hydroxyeicosatetraenoic acid in greater quantities than analogous pulmonary arteries from the experimental left or control pulmonary arteries. CONCLUSIONS: Forty-eight hours after anastomosis, enhanced reactivity of contralateral pulmonary arteries is attributable in part to increased lipoxygenase products as opposed to nitric oxide or other eicosanoid products.

Effects of a localized high-flow anastomosis between the aorta and left lower lobe pulmonary artery on great vessel flow and pulmonary arterial reactivity in the contralateral lung.

OBJECTIVES: We sought to assess the effects of a localized anastomosis between the aorta and left lower lobe pulmonary artery on flows through central vessels and on the vascular reactivity of small pulmonary arteries distal or contralateral to the shunt. METHODS: Flow rates in major vessels and tensions from small pulmonary arteries from the left and right lower lobes were determined 48 hours after creation of an end-to-side anastomosis of the left lower lobe pulmonary artery to the aorta. RESULTS: Anastomoses increased flow through the left lower lobe pulmonary artery from 194±6 to 452±18 mL/min immediately after anastomosis to 756±19 mL/min by the time of harvest (n=88, P<.05). Flow rates in main pulmonary arteries from hosts with anastomoses were lower (557±26 vs 1033±244 mL/min), whereas aortic root flows were not different from control values (1370±53 vs 1120±111 mL/min; P=.07). Wet/dry weights of both lungs and aortic flow rates were proportional to shunt flow rates. Pulmonary artery rings harvested from the right (unshunted) lobes of high-flow hosts exhibited increased reactivity to the thromboxane agonist U46619 and phenylephrine relative to those of left pulmonary arteries from the same animal or those of control hosts. CONCLUSIONS: Our studies are the first to identify enhanced reactivity of pulmonary arteries in a lung contralateral to a localized high-output shunt between an aorta and pulmonary artery. These observations suggest that patients with localized systemic-to-pulmonary shunt could exhibit modified vascular tone in remote pulmonary arteries.