Search PubMed⌕ Search

Biomedical subjects

Todd E Rasmussen

Publications and source records attributed to Todd E Rasmussen.

At least 19 recordsLinked to original sources
PubMed2006

Upper extremity vascular injury: a current in-theater wartime report from Operation Iraqi Freedom.

Past wartime experience and recent civilian reports indicate upper extremity (UE) vascular injury occurs less often and with less limb loss than lower extremity (LE) injury. Given advances in critical care, damage control techniques, and military armor technology, the objective of this evaluation was to define contemporary patterns of UE injury and effectiveness of vascular surgical management in UE vascular injury during Operation Iraqi Freedom (OIF). From 1 September 2004 through 31 August 2005, 2,473 combat-related injuries were treated at the central echelon III surgical facility in Iraq. Patients with UE vascular injuries upon arrival were reviewed. Vessels injured were delineated. Therapeutic interventions, early limb viability, and complication rates following vascular repair were recorded. Of casualties treated during the study period, 43 (1.7%) UE and 83 (3.3%) LE vascular injuries were identified. Of the UE injuries, 11 (26%) had been operated on at forward locations and six (14%) had temporary shunts in place upon arrival at our facility. Injury levels included 10 (23%) subclavian-axillary, 25 (58%) brachial, and 10 (23%) distal to the brachial bifurcation. Two patients had multilevel injury. Twenty-eight grafts were placed, and 10 vessel repairs and eight ligations were performed. Two (4.7%) brachial interposition grafts required removal due to infection. Four (9.3%) subacute brachial graft thromboses occurred. Four (9.3%) patients underwent early UE amputation. In this most recent U.S. military evaluation of wartime UE vascular injury, UE injury appears rare, with LE injury twice as frequent. Yet, UE limb loss appears more substantial than noted previously. These findings are likely related to significant tissue destruction occurring with the combined mechanisms of injury sustained in OIF.

Amputation, Surgical↗
PubMed2006

Children treated at an expeditionary military hospital in Iraq.

OBJECTIVE: To describe the treatment of children at an expeditionary military hospital in wartime Iraq. DESIGN: Descriptive, retrospective study. SETTING: The 332nd Air Force Theater Hospital in Balad, Iraq, January 1, 2004, to May 31, 2005. PATIENTS: All 85 children (of 1626 total patients) evaluated and treated at the hospital during the study period. INTERVENTIONS: Indicated surgical procedures performed on children. MAIN OUTCOME MEASURES: Age, sex, diagnosis, injury, operations, and complications for children during the study period. RESULTS: The 85 children (age range, 1 day to 17 years; mean, 8 years) represented 5.2% of all patients. Thirty-four (61%) of the 56 children for whom sex was recorded were male. Injury was the diagnosis for 48 children (56%). Of these, the cause was fragmentation wound in 25 children (52%), penetrating trauma in 11 (23%), burn in 9 (19%), and blunt trauma in 3 (6%). The site of injury was the lower extremity in 18 children (38%), head in 11 (23%), upper extremity in 8 (17%), abdomen in 8 (17%), and chest in 3 (6%). Nontraumatic conditions had congenital, infectious, gastrointestinal, and neoplastic causes. During the study, 134 operations were performed on 63 children. There were 5 deaths. CONCLUSIONS: Expeditionary military hospitals will encounter both injured and noninjured children seeking medical care. To optimize the care of these children, it will be necessary to provide the proper personnel, training, and equipment.

Adolescent↗
PubMed2006

The use of temporary vascular shunts as a damage control adjunct in the management of wartime vascular injury.

BACKGROUND: While the use of vascular shunts as a damage control adjunct has been described in series from civilian institutions no contemporary military experience has been reported. The objective of this study is to examine patterns of use and effectiveness of temporary vascular shunts in the contemporary management of wartime vascular injury. MATERIALS: From September 1, 2004 to August 31, 2005, 2,473 combat injuries were treated at the central echelon III surgical facility in Iraq. Vascular injuries were entered into a registry and reviewed. Location of shunts was divided into proximal and distal, and shunt patency, complications and limb viability were examined. RESULTS: There were 126 extremity vascular injuries treated. Fifty-three (42%) had been operated on at forward locations and 30 of 53 (57%) had temporary shunts in place upon arrival to our facility. The patency for shunts in proximal vascular injuries was 86% (n = 22) compared with 12% (n = 8) for distal shunts (p < 0.05). All shunts placed in proximal venous injuries were patent (n = 4). Systemic heparin was not used and there were no shunt complications. All shunted injuries were reconstructed with vein in theater and early viability for extremities in which shunts were used was 92%. CONCLUSIONS: Temporary vascular shunts are common in the management of wartime vascular injury. Shunts in proximal injuries including veins have high patency rates compared with those placed in distal injuries. This vascular adjunct represents a safe and effective damage control technique and is preferable to attempted reconstruction in austere conditions.

Blood Vessel Prosthesis Implantation↗
PubMed2006

Experience with wound VAC and delayed primary closure of contaminated soft tissue injuries in Iraq.

BACKGROUND: Wartime missile injuries are frequently high-energy wounds that devitalize and contaminate tissue, with high risk for infection and wound complications. Debridement, irrigation, and closure by secondary intention are fundamental principles for the management of these injuries. However, closure by secondary intention was impractical in Iraqi patients. Therefore, wounds were closed definitively before discharge in all Iraqi patients treated for such injures at our hospital. A novel wound management protocol was developed to facilitate this practice, and patient outcomes were tracked. This article describes that protocol and discusses the outcomes in a series of 88 wounds managed with it. METHODS: High-energy injuries were treated with rapid aggressive debridement and pulsatile lavage, then covered with negative pressure (vacuum-assisted closure [VAC]) dressings. Patients underwent serial operative irrigation and debridement until wounds appeared clean to gross inspection, at which time they were closed primarily. Patient treatment and outcome data were recorded in a prospectively updated database. RESULTS: Treatment and outcomes data from September 2004 through May 2005 were analyzed retrospectively. There were 88 high-energy soft tissue wounds identified in 77 patients. Surprisingly, for this cohort of patients the wound infection rate was 0% and the overall wound complication rate was 0%. CONCLUSION: This series of 88 cases is the first report of the use of a negative pressure dressing (wound VAC) as part of the definitive management of high-energy soft tissue wounds in a deployed wartime environment. Our experience with these patients suggests that conventional wound management doctrine may be improved with the wound VAC, resulting in earlier more reliable primary closure of wartime injuries.

Bandages↗
PubMed2006

Echelons of care and the management of wartime vascular injury: a report from the 332nd EMDG/Air Force Theater Hospital, Balad Air Base, Iraq.

The objective of this report is to provide a contemporary in-theater account on the systematic management of wartime vascular injury. Included are strategies at each echelon of care that affect the treatment of these injuries. In addition, the aim of this report is to present a modern wartime vascular registry describing rates and distribution of injury in what is now a mature military conflict. A 15-month review (September 1, 2004 through December 1, 2005) from the central level III echelon facility in Iraq (332nd EMDG/Air Force Theater Hospital) presented by the in-theater Consultants for Vascular Surgery. During this period 13 460 casualties were treated at or evacuated through our location, 3096 (23%) with battle-related injuries. Vascular injuries comprised 6.6% (N = 209) of battle-related trauma in the following distribution: extremity 79% (n = 166), neck 13% (n = 27), thoracoabdominal 8% (n = 16). Three levels (formerly echelons) of care are active in theater each with strategies that affect vascular injury management: Level 1: use of commercial tourniquets; level 2: use of temporary vascular shunts as damage control adjuncts; and level 3: definitive repair of arterial and venous injuries in theater using autologous vein. Evacuation patterns and the position of the Air Force Theater Hospital have allowed the formation of a contemporary wartime vascular registry. The rate of vascular injury appears increased compared to that of Vietnam with extremity injuries most prevalent. Effective strategies are in place at each of 3 levels of care that affect the management of vascular injury.

Blood Vessels↗
PubMed2006

Management of blunt peripheral arterial injury.

The recognition of blunt vascular injury has increased in recent years due to an improved understanding of blunt mechanical forces, mechanisms of injury, and awareness that such injuries are often occult. This has been aided by improved quality and expanded availability of noninvasive studies. As a result, outcomes following blunt vascular injury have improved. Compared to penetrating vascular injury and other vascular disease processes, blunt vascular injury has unique features that make it useful to consider as a distinct clinical entity. Manifestations of blunt vascular injury may develop in a delayed fashion and present with more subtle findings, such as a pulse deficit or diminished ankle-brachial pressure index. The objective of this review is to present a brief historical perspective on blunt vascular injury as well as an appraisal of current diagnostic and treatment strategies. Blunt vascular injury will be discussed in distinct anatomic regions, including cervical and upper and lower extremity and evidence-based management strategies developed.

Angiography↗
PubMed2005

The endovascular management of recurrent aortic hypoplasia and coarctation in a 15-year-old male.

A 15-year-old male complained of easy fatigability, leg weakness, and pain on exertion with episodes of syncope while playing baseball. His past medical history was significant for aortic coarctation associated with a congenital bovine hypoplastic aortic arch. A recent arteriogram revealed innominate and left common carotid artery stenosis as well as recurrent coarctation. He had previously undergone three Dacron patch aortoplasties. At the age of 7, he underwent a fourth operation for recurrent coarctation and because of extensive scar tissue in the region of his prior procedures, a left subclavian artery-to-descending aortic bypass was performed. An endovascular repair to deal with the recent recurrence was performed because of prior surgical difficulties. Percutaneous balloon-expandable stents were placed in the aortic coarctation, innominate, and the left common carotid arteries. Postprocedure, ankle brachial indices were >1 and the patient remains asymptomatic after 1 year.

Adolescent↗
PubMed2005

What imaging studies are necessary for abdominal aortic endograft sizing? A prospective blinded study using conventional computed tomography, aortography, and three-dimensional computed tomography.

OBJECTIVE: Preoperative imaging modalities for endovascular abdominal aortic aneurysm repair (EVAR) include conventional computed tomography (CT), aortography with a marking catheter, and three-dimensional computed tomography (3D CT). Although each technique has advantages, to date no study has compared in a prospective manner the reproducibility of measurements and impact on graft selection of all three modalities. The objective of this study was to determine the most useful imaging studies in planning EVAR. METHODS: Twenty patients being considered for EVAR were enrolled prospectively to undergo a conventional CT scan and aortography. The CT scans were then reconstructed into 3D images using Preview Treatment Planning Software (Medical Media Systems, West Lebanon, NH). Four measurements of diameter and six of length were made from each modality in determining the proper graft for EVAR. RESULTS: Measurements from all three modalities were reproducible with intraobserver correlation coefficients of 0.79 to 1.0 for aortography, 0.87 to 1.0 for CT, and 0.96 to 1.0 for 3D CT. Measurements between observers were also similar from each modality; interobserver correlations were 0.70 to 0.97 for aortography, 0.76 to 0.97 for CT, and 0.73 to 0.99 for 3D CT. Significant differences ( P < .01) in diameter measurements were noted at D2 with aortography compared with 3D CT, whereas differences in length measurements were found between CT and 3D CT at L4 (nonaneurysmal right iliac) ( P < .01). The correlation between CT and 3D CT for most length measurements was acceptable (0.63 to 1.0). Aortography for diameters correlated poorly (0.35 to 0.67) with 3D CT. When the endograft selected by aortography/CT or 3D CT alone was compared with the actual endograft used, there was agreement in 11 of 11 patients when adjusted for +/- one size in diameter or length. CONCLUSION: Reproducible and comparable measures of diameter and length can be obtained by each of three imaging modalities available for endograft sizing. As a single imaging modality, 3D CT appears to have the best correlation for both diameters and lengths; however, the difference is not sufficient enough to alter endograft selection. Three-dimensional CT may be reserved for challenging aortic anatomy where small differences in measurements would affect patient or graft selection for EVAR.

Aged↗
PubMed2005

Contemporary management of wartime vascular trauma.

OBJECTIVE: The treatment of wartime injuries has led to advances in the diagnosis and treatment of vascular trauma. Recent experience has stimulated a reappraisal of the management of such injuries, specifically assessing the effect of explosive devices on injury patterns and treatment strategies. The objective of this report is to provide a single-institution analysis of injury patterns and management strategies in the care of modern wartime vascular injuries. METHODS: From December 2001 through March 2004, all wartime evacuees evaluated at a single institution were prospectively entered into a database and retrospectively reviewed. Data collected included site, type, and mechanism of vascular injury; associated trauma; type of vascular repair; initial outcome; occult injury; amputation rate; and complication. Liberal application of arteriography was used to assess these injuries. The results of that diagnostic and therapeutic approach, particularly as it related to the care of the blast-injured patient, are reviewed. RESULTS: Of 3057 soldiers evacuated for medical evaluation, 1524 (50%) sustained battle injuries. Known or suspected vascular injuries occurred in 107 (7%) patients, and these patients comprised the study group. Sixty-eight (64%) patients were wounded by explosive devices, 27 (25%) were wounded by gunshots, and 12 (11%) experienced blunt traumatic injury. The majority of injuries (59/66 [88%]) occurred in the extremities. Nearly half (48/107) of the patients underwent vascular repair in a forward hospital in Iraq or Afghanistan. Twenty-eight (26%) required additional operative intervention on arrival in the United States. Vascular injuries were associated with bony fracture in 37% of soldiers. Twenty-one of the 107 had a primary amputation performed before evacuation. Amputation after vascular repair occurred in 8 patients. Of those, 5 had mangled extremities associated with contaminated wounds and infected grafts. Sixty-seven (63%) patients underwent diagnostic angiography. The most common indication was mechanism of injury (42%), followed by abnormal examination (33%), operative planning (18%), or evaluation of a repair (7%). CONCLUSIONS: This interim report represents the largest analysis of US military vascular injuries in more than 30 years. Wounding patterns reflect past experience with a high percentage of extremity injuries. Management of arterial repair with autologous vein graft remains the treatment of choice. Repairs in contaminated wound beds should be avoided. An increase in injuries from improvised explosive devices in modern conflict warrants the more liberal application of contrast arteriography. Endovascular techniques have advanced the contemporary management and proved valuable in the treatment of select wartime vascular injuries.

Adult↗
PubMed2004

Evidence of nanobacterial-like structures in calcified human arteries and cardiac valves.

Mechanisms mediating vascular calcification remain incompletely understood. Nanometer scale objects hypothesized to be a type of bacteria (nanobacteria) are associated with calcified geological specimens, human kidney stones, and psammona bodies in ovarian cancer. Experiments were designed to evaluate human vascular tissue for the presence of similar nanometer-scale objects. Calcified human aneurysms (n = 8), carotid plaques (n = 2), femoral arterial plaques (n = 2), and cardiac valves (n = 2) and noncalcified aneurysms from patients with bicuspid aortic valve disease (n = 2) were collected as surgical waste from the Heart Hospital of Austin, Austin, Texas, and Mayo Clinic, Rochester, Minnesota. Whole mounts or adjacent sections from each specimen were examined by electron microscopy, stained for calcium phosphate, or stained with a commercially available antibody (8D10). Filtered (0.2 microm) homogenates of aneurysms were cultured and costained with 8D10 antibody followed by PicoGreen to detect DNA or incubated with [3H]uridine. Staining for calcium phosphate was heterogeneously distributed within all calcified tissues. Immunological staining with 8D10 was also heterogeneously distributed in areas with and without calcium phosphate. Analysis of areas with positive immunostaining identified spheres ranging in size from 30 to 100 nm with a spectral pattern of calcium and phosphorus (high-energy dispersive spectroscopy). Nanosized particles cultured from calcified but not from noncalcified aneurysms were recognized by a DNA-specific dye and incorporated radiolabeled uridine, and, after decalcification, they appeared via electron microscopy to contain cell walls. Therefore, nanometer-scale particles similar to those described as nanobacteria isolated from geological specimens and human kidney stones can be visualized in and cultured from calcified human cardiovascular tissue.

Aged↗
PubMed2003

Endovascular assisted in situ bypass grafting: a simplified technique for saphenous vein side branch occlusion.

The in situ bypass procedure for lower extremity limb salvage requires a long continuous incision or multiple interrupted incisions over the greater saphenous vein to ligate the saphenous vein side branches. This can result in wound complications that frequently prolong hospital stay and threaten the graft. In an effort to reduce the incidence of wound complications, alternate methods of occluding the vein side branches have been used. One method is to deliver coils under angioscopic vision into the saphenous vein side branches. This report details a simplified technique that uses widely available catheter-based equipment to perform saphenous vein side branch occlusion under fluoroscopic guidance.

Embolization, Therapeutic↗
PubMed2003

Intraoperative use of a new angle-independent Doppler system to measure arterial velocities after carotid endarterectomy.

OBJECTIVE: The purpose of this study was to assess the intraoperative use of a new angle-independent ultrasound scan device (EchoFlow [EF]) in measurement of carotid artery velocities after endarterectomy. Specifically, the purpose was to determine the reproducibility of velocity measurements obtained with EF and to compare these measurements with the velocity measurements obtained with duplex ultrasound scan. METHODS: Velocity measurements of the common, internal, and external carotid arteries were performed by the operative surgeon with EF in 65 consecutive patients after carotid endarterectomy (36 female, 29 male; mean age, 71 years). Three velocity measurements were obtained from each of the arteries with EF and compared with the velocity measurements obtained with duplex ultrasound scan performed by a radiologist. RESULTS: Velocity measurements obtained with the EF device were reproducible in the common, internal, and external carotid arteries (intrapatient correlation coefficients, 0.95, 0.96, and 0.95, respectively). Seventy-five percent of common, 88% of internal, and 78% of external carotid velocity measurements obtained with the angle-independent ultrasound scan device were within 25 cm/s of the velocities measured with duplex ultrasound scan. The mean differences in velocity measurements between EF and duplex scan were -12 cm/s in the common, -8 cm/s in the internal, and -11 cm/s in the external carotid arteries. Differences between the EF device and duplex scan velocity measurements correlated with increasing arterial velocities in each of the three arteries measured (P <.05). CONCLUSION: Reproducible measurements of carotid artery velocity may be obtained with a new angle-independent Doppler system after endarterectomy. Most measurements obtained with the EF system are clinically comparable with those obtained with standard duplex ultrasound scan. This novel low-cost device may be useful in the intraoperative assessment of hemodynamic adequacy of carotid endarterectomy.

Aged↗
PubMed2002

Early abdominal closure with mesh reduces multiple organ failure after ruptured abdominal aortic aneurysm repair: guidelines from a 10-year case-control study.

OBJECTIVE: The objectives of this study were the comparison of patients who needed mesh closure of the abdomen with patients who underwent standard abdominal closure after ruptured abdominal aortic aneurysm repair and the determination of the impact of timing of mesh closure on multiple organ failure (MOF) and mortality. METHODS: We performed a case-control study of patients who needed mesh-based abdominal closure (n = 45) as compared with patients who underwent primary closure (n = 90) after ruptured abdominal aortic aneurysm repair. RESULTS: Before surgery, the patients who needed mesh abdominal closure had more blood loss (8 g versus 12 g of hemoglobin; P <.05), had prolonged hypotension (18 minutes versus 3 minutes; P <.01), and more frequently needed cardiopulmonary resuscitation (31% versus 2%; P <.01) than did the patients who underwent primary closure. During surgery, the patients who needed mesh closure also had more severe acidosis (base deficit, 14 versus 7; P <.01), had profound hypothermia (32 degrees C versus 35 degrees C; P <.01), and needed more fluid resuscitation (4.0 L/h versus 2.7 L/h; P <.01). With this adverse clinical profile, the patients who needed mesh closure had a higher mortality rate than did the patients who underwent primary closure (56% versus 9%; P <.01). However, the patients who underwent mesh closure at the initial operation (n = 35) had lower MOF scores (P <.05), a lower mortality rate (51% versus 70%), and were less likely to die from MOF (11% versus 70%; P <.05) than the patients who underwent mesh closure after a second operation in the postoperative period for abdominal compartment syndrome (n = 10). CONCLUSION: This study reports the largest experience of mesh-based abdominal closure after ruptured abdominal aortic aneurysm repair and defines clinical predictors for patients who need to undergo this technique. Recognition of these predictors and initial use of mesh closure minimize abdominal compartment syndrome and reduce the rate of mortality as the result of MOF.

Aged↗
PubMed2002

Human leukocyte antigen class II immune response genes, female gender, and cigarette smoking as risk and modulating factors in abdominal aortic aneurysms.

OBJECTIVE: Aortic inflammation and the genes that regulate the immune response play an important role in abdominal aortic aneurysm pathogenesis. However, the modulating effects of such genetic and other environmental factors on the severity on aneurysm inflammation is not known. The objective of this study was to determine the influence of the human leukocyte antigen (HLA) class II genes, gender, and environmental factors on degree of abdominal aortic aneurysm tissue inflammation. METHODS: Aneurysm specimens were obtained at the time of operation from 96 consecutive patients who underwent abdominal aortic aneurysm repair and were graded for degree of histologic inflammation. Multivariate analysis was used to determine the association of genetic and environmental factors with degree of inflammation and to determine the HLA-associated disease risk for aneurysm. RESULTS: Active cigarette smoking and female gender were independently associated with high-grade tissue inflammation identified histologically (odds ratio [OR], confidence interval [CI]: 5.6, 1.6 to 19.3; and 6.0, 1.4 to 26.2, respectively), and a specific HLA allele (DR B1(*)01) was inversely associated with inflammation (OR, CI: 0.2, 0.04 to 0.7). Overall, the HLA-DR B1(*)02 and B1(*)04 alleles were significantly associated with disease risk, more than doubling risk for abdominal aortic aneurysm (OR, CI: 2.5, 1.4 to 4.3; and 2.1, 1.2 to 3.7, respectively). CONCLUSION: Active cigarette smoking and female gender are significant disease-modulating factors associated with increased abdominal aortic aneurysm inflammation. In addition, the HLA class II immune response genes possess both disease modulating and disease risk properties, which may be useful in early aneurysm detection and surveillance.

Aged↗