PubMed HealthSearch

Biomedical subjects

A W Fleming

Publications and source records attributed to A W Fleming.

At least 19 recordsLinked to original sources

Aortoesophageal fistulae due to gunshot wounds: report of two cases with one survivor.

We report the cases of two patients who developed aortoesophageal fistulae after sustaining gunshot wounds to the chest. One suddenly exsanguinated 5 hours postinjury while in the angiography suite. The other manifested 4 weeks postinjury while in a rehabilitation hospital for associated spinal cord injury. The diagnosis and management were complicated, but the patient lived. He is the only survivor of aortoesophageal fistula due to gunshot wound that we could find in the literature.

Adolescent

Incidence of cervical spine injury in patients with gunshot wounds to the head.

Cervical spine immobilization is standard during the early stages of prehospital and hospital care of patients with blunt head injury. However, the need for cervical spine immobilization in patients with gunshot wounds to the head has not been addressed. To determine the incidence and types of cervical spine injury in this group, we retrospectively examined the records of 308 consecutive patients who had computed tomographic (CT) scans of the head to evaluate brain injury after gunshot wounds. Of the 266 patients with data adequate for review, 157 (59%) had a complete lateral x-ray film of the cervical spine. Of these 157, 105 had wounds limited to the calvaria, and none had cervical spine injury. Of 52 patients with complete lateral x-ray films and wounds not limited to the calvaria, 5 (10%) had cervical spine or spinal cord injury. Of the 192 patients who had CT-proven intracranial injury, 86 (45%) required immediate intubation before x-ray films were obtained, and 67 (35%) died. We conclude that cervical spine immobilization may not be required during endotracheal intubation of brain-injured gunshot victims with wounds limited to the calvaria.

Brain Injuries

Management of penetrating colon injuries.

The management of colon injuries remains an area of major controversy. Selecting the patients who can undergo primary repair safely remains undefined. To address this issue, 231 consecutive patients with penetrating colon injuries were reviewed to determine those factors that affected outcome. Overall, there were 54 (25.2%) septic complications, with 36 (16.8%) wound infections and 18 (8.4%) intra-abdominal abscesses. There were seven (3.3%) deaths in the entire series. The surgical management method of the colon injury was not significant in wound infections (P > .39), intra-abdominal abscesses (P > .24), or mortality (P > .39). A more aggressive approach of primary repair should be performed for civilian colon injuries.

Abscess

Injury and violence in Los Angeles. Impact on access to health care and surgical education.

The Los Angeles County (California) Trauma Hospital System was designed to ensure that all patients requiring specialized trauma care would be transported directly to a trauma center using established trauma triage criteria. The designation and implementation of all level 1, 2, and 3 (rural) trauma centers were completed between October 1983 and July 1985. However, by February 1, 1985, one level 2 trauma center withdrew, and nine other level 2 and 3 trauma centers followed suit over the next few months and years. The reasons for closure of these 10 trauma centers were almost exclusively related to economic factors. The major impact of trauma center closure on surgical educational programs at the Drew University of Medicine and Science and the Martin Luther King, Jr/Charles R. Drew Medical Center have been additive and cumulative. The high volume of patients with trauma has been cited, sometimes correctly and sometimes incorrectly, as the primary reason for a lack of access to health care for patients without trauma. We have developed a blueprint for survival that, when fully implemented, will improve access to health care for all residents in our catchment area and optimize surgical education. While the Los Angeles County Trauma Hospital System has had many difficulties during the last 9 years, the population it serves is greater than that in 42 states in the United States. The experiences gained in Los Angeles County may be beneficial to statewide systems in the United States and in countries of comparable size.

General Surgery

Time-related effects of heparin sulfate on regional and systemic anticoagulation.

Optimal timing of vascular clamping to anticoagulation during cardiovascular surgical procedures is poorly defined. This study uses a canine model to determine the effectiveness of three different methods of heparin administration. Heparin sulfate (150 IU/kg) was administered by: injection into the jugular vein 5 minutes before infrarenal aortic clamping (Group 1), injection into the terminal aorta immediately after infrarenal aortic clamping (Group 2), and injection into the jugular vein immediately after infrarenal aortic clamping (Group 3). Thrombin clotting times and partial thromboplastin times were measured in venous blood from the upper and lower extremities before (baseline) heparin administration, and 1, 3, and 5 minutes following heparin administration. Activated clotting times were assessed in lower extremity blood at baseline, and at 1 and 5 minutes after heparin injection. Significant differences existed between groups in both upper and lower extremities. Systemic anticoagulation occurred within 1 minute after intravenous heparin administration in Groups 1 and 2 in the lower extremity, and Groups 1 and 3 in the upper extremity. Delayed anticoagulation in the lower extremity was noted with systemic injection after aortic clamping in Group 3, and after regional intra-aortic administration in the upper extremity of Group 2 subjects. Complete anticoagulation was noted by 5 minutes in all groups in both the upper and lower extremities. These results suggest that the safe time period between heparin administration and vascular clamping varies with the route and the timing of its administration. Intravenous administration prior to aortic cross-clamping provided adequate anticoagulation in this canine model in both the upper and lower extremity blood after 1 minute of heparin circulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Evaluation of a blunt and penetrating trauma algorithm for truncal injury.

The authors objective was to develop and test a single branch-chain decision tree for blunt and penetrating truncal injury. Over the 4-month study period there were 979 patients evaluated in the emergency department; 674 of these patients were admitted to the hospital. Thirty-four (5%) of the 674 admitted patients died of truncal injury. The study group consisted of 239 of the most severely injured patients; 41 of these (17%) died. Of the 44 patients managed with major deviations from the algorithm, 27 (61%) died. Only 14 of the 195 patients (7%) whose management complied with the algorithm died. The authors conclude that following the specific management criteria outlined by the algorithm may improve the survival of severely traumatized patients.

Abdominal Injuries

The efficacy of central venous and pulmonary artery catheters and therapy based upon them in reducing mortality and morbidity.

The purpose of this study was to (1) evaluate the relative cost effectiveness of the central venous pressure and flow-directed pulmonary artery catheters used to maintain normal hemodynamic values as therapeutic goals in the control groups vs supranormal values empirically observed in critically ill postoperative survivors in the protocol groups, and (2) to evaluate tissue perfusion and oxygenation in relationship to organ failure and mortality. In two prospective clinical trials there were no significant differences in outcome between the central venous pressure and pulmonary artery control groups that used normal values as therapeutic goals. However, there were marked and significant reductions in morbidity and mortality of the protocol groups using the supranormal cardiac index, oxygen delivery, and oxygen consumption values as goals. The cumulative oxygen debt was less and organ failures were fewer and less severe in the protocol groups than in the control groups.

Cardiac Output

Fibrin glue achieves hemostasis in patients with coagulation disorders.

Fibrin glue (FG), made with highly concentrated human fibrinogen and clotting factors, was used to achieve parenchymal organ hemostasis in patients with disordered coagulation secondary to massive transfusion, chronic disease, and disseminated intravascular coagulation; it was effective in controlling liver hemorrhage in seven patients and in the performance of a splenorrhaphy in one other patient. The coagulation profile was grossly abnormal in all patients, and the mean +/- SD intraoperative blood loss was 5.1 +/- 4.2 L; patients received 14 +/- 10 U of blood perioperatively. The amount of FG required to achieve hemostasis varied directly with the extent of injury and intraoperative blood loss (r = .84), and all patients with a blood loss greater than 4 L required at least 25 mL of FG to stop bleeding. Two patients died postoperatively secondary to cardiac arrest and adult respiratory distress syndrome. Because FG does not depend on adequate platelet or clotting factor levels to be effective, it is especially useful in patients with parenchymal organ hemorrhage and disordered coagulation.

Adult

Development and testing of a decision tree for blunt trauma.

The aim of the present study was to examine the essential problems in a retrospective study of 381 organ injuries in 260 patients, to identify problems, to define criteria, to describe decision rules, and to organize these rules into branch-chain decision trees or clinical algorithms. The basic hypothesis of this study is that criteria organized into a prioritized decision tree can provide objective standards to evaluate the quality of trauma care and to compare alternative approaches. The algorithm was designed to provide prompt therapy for the most life-threatening problems: respiratory and cardiac arrest, shock, head injury, tamponade, lacerations of the great vessels, cardiac contusion, ruptured parenchymal organs, lacerated viscera, and injury to other intraperitoneal organs. Resuscitation from shock, correction of circulatory problems, and monitoring of physiologic variables were prioritized to evaluate the presence of circulatory deficits and the adequacy of specific therapy to correct them. Concomitantly, diagnosis of the underlying problems was approached using peritoneal lavage, abdominal and chest x-rays, iv urograms, cystograms, endoscopy, upper and lower GI barium or hypaque studies, ultrasound, scintograms, and CT scans. In emergency conditions these are limited to a large extent by time factors. The diagnostic accuracy, priorities, and limitations of each of these were evaluated in emergency conditions. The algorithm was used to track management decisions in a prospective series; the mortality of 51 patients with satisfactory compliance was 4% and 44% in nine patients with major deviations from the algorithm.

Adult

Use of fibrin glue in hepatic trauma.

We evaluated the efficacy and safety of fibrin glue (FG) made with highly concentrated human fibrinogen and clotting factors in achieving hemostasis of superficial and deep hepatic injuries. Experimentally produced hepatic injuries were produced in 12 adult mongrel dogs and hemostatically sealed with FG. Half of the dogs each received two penetrating hepatic injuries consisting of a large laceration and a deep stab wound through the liver; the remaining dogs underwent resection of a large segment of the left lobe of the liver. Hemostasis was achieved by applying FG into and over the bleeding wounds; hepatic arterial occlusion was not used. Complete hemostasis was achieved in all animals before skin closure. One dog from each group was re-explored and the liver specimens harvested for gross and microscopic examination at postoperative intervals of 12 hours, 24 hours, and 2, 3, 6, and 8 weeks. There were no cases of intra-abdominal infection, abscess formation, or bile fistulae. Histologic examination demonstrated a thickened capsule containing fibrous connective tissue and neovascular proliferation; there were no signs of local or systemic toxicity. One dog died on postoperative day 1 from rebleeding from the hepatic injury; all other dogs survived without complications. We conclude that FG provides effective hemostasis of superficial and deep hepatic injuries, and has good systemic and local compatibility. Its use in surgery for hepatic trauma may lead to less intraoperative blood loss and transfusion requirements, as well as a reduced need for major hepatic resection to control hemorrhage.

Animals

Determination of optimal positive end-expiratory pressure by means of conjunctival oximetry.

A method for determining the optimal level of positive end-expiratory pressure (PEEP) by means of noninvasive conjunctival oxygen (PcjO2) monitoring and arterial blood gas analysis was developed from the pattern of changes in PcjO2 tension, invasive hemodynamic parameters, and oxygen transport variables during PEEP titration in a series of patients with adult respiratory distress syndrome. All patients had radial and pulmonary artery (PA) catheters inserted and blood volume was measured with 125I serum albumin before each study. During progressive increases in the level of PEEP, PcjO2 tensions reflected changes in both PaO2 and cardiac index (CI), depending on whether PEEP produced a significant decrease in CI. In patients with a stable CI, PcjO2 tensions tracked PaO2 values (rw = 0.92); in patients with a greater than a 15% decrease in CI, the conjunctival index, CjI (defined as the PcjO2/PaO2 ratio), tracked CI (rw = 0.87), excluding one patient with high cardiac output-septic shock and severe hypoxemia. PcjO2 correlated with PaO2 in the latter patient (r = 0.99) probably because conjunctival oxygen transport was limited by arterial oxygen content (PaO2 = 34 torr) rather than blood flow (CI greater than 6 L/min X m2). In patients with a greater than a 10% decrease in CI as a result of PEEP, the greater the decrease in CI, the better CjI values correlated with CI. We conclude that PcjO2 monitoring combined with repeated arterial blood gas analysis may be used to titrate PEEP therapy in patients with adult respiratory distress syndrome. In patients whose CjI significantly decreases because of PEEP, PA catheterization and measurement of cardiac output are indicated because of the likelihood of a significant (greater than 15%) decrease in CI. In the absence of a significant decrease in the CjI, optimum PEEP occurs at the level producing maximum PcjO2. It is hoped that by following the described algorithm, many patients will be spared the cost and morbidity of unnecessary PA catheterization.

Adult

The utilization of cross-sectional anatomy in a surgical residency training program.

The education of students and residents in a surgical department involves a thorough knowledge of three-dimensional anatomical relationships in the body. In addition, the advances in new imaging modalities demand an in-depth study of cross-sectional anatomy by both students and residents. Traditionally, surgical training incorporated dissections of cadavers and the progressive involvement of the resident in the surgical theater. At the King/Drew Medical Center cross-sectional anatomy has been incorporated into the teaching program. The central focus of this instructional program utilizes problem-solving learning modules that emphasize important surgical and anatomical principles.LEARNING MODULES FOR EACH MAJOR REGION OF THE BODY WERE ESTABLISHED AND INCLUDE THE FOLLOWING: (1) serial cross sections, corresponding computerized tomographic scans and roentgenograms; (2) an atlas (cross sections), case histories, and examination questions; and (3) audiovisual presentation of the normal anatomy, the surgical principles involved, and a discussion of the examination questions. The serial cross sections were prepared at the King/Drew Medical Center.A selected case study is used to illustrate how the knowledge of three-dimensional anatomy can be critical in the evaluation and surgical plan of a patient. Entire learning modules of the thorax and abdomen were used.

Abdomen

Noninvasive conjunctival oxygen monitoring during carotid endarterectomy.

Conjunctival oxygen tension (PcjO2) was measured continuously during carotid endarterectomy in 15 patients to evaluate its sensitivity in patients receiving shunts. These studies suggest that PcjO2 tracks brain perfusion during periods of carotid artery occlusion. Reduced PcjO2 was clearly demonstrated with systemic hypotension, carotid artery clamping, and carotid shunt obstruction and clamping. Monitoring of PcjO2 is noninvasive, easy to perform, offers no danger to the patient, and allows real-time assessment of the local tissue perfusion. It provides valuable information on the effectiveness of carotid oxygen transport and, in conjunction with arterial blood gas values, expresses carotid artery perfusion relative to systemic oxygen transport. Further investigations using the PcjO2 sensor may define criteria for intraoperative carotid arterial shunting in patients with tenuous cerebral perfusion, and for prompt intervention in patients with deteriorating perfusion prior to the onset of life-threatening cerebral ischemia.

Aged

Resuscitation of the trauma patient: restoration of hemodynamic functions using clinical algorithms.

Two algorithms were developed for immediate fluid resuscitation and subsequent management of emergency trauma patients and critically ill postoperative patients. These algorithms were developed from decision rules based on objective physiologic values attained in patients surviving life-threatening shock and trauma. The improved mortality in prospective studies of these two algorithms supports the hypothesis that compensatory physiologic responses of survivors of life-threatening acute illness are major determinants of outcome. Therapy that supports these compensations and produces the survivor pattern was found to improve survival rates and reduce post-resuscitation complications. These prospective studies confirm the validity of an organized, coherent physiologic approach that has as its goal the achievement of optimal physiologic patterns in contrast to simple restoration of hemodynamic and chemical abnormalities to the normal range, as has been the endpoint of the traditional approach.

Adult

Assessment of intestinal and renal perfusion using surface oximetry.

Using a miniaturized polarographic oxygen sensor, we studied the sequential effects of graded hypoxia and standardized hemorrhagic shock on organ surface oxygen tension (PsO2) measurements obtained from the canine small intestine and kidney. During hypoxia, intestinal and renal PsO2 values decreased along with PaO2. The weighted mean correlation coefficients for intestinal and renal PsO2 vs. PaO2 were 0.94 and 0.98, respectively. During severe hypoxia, intestinal and renal PsO2 values fell by 55 +/- 8% and 55 +/- 7% (SEM), respectively, while oxygen delivery fell by 58 +/- 10% (SEM). During active hemorrhage, intestinal and renal PsO2 values decreased along with cardiac output, while PaO2 remained relatively constant. Intestinal and renal PsO2 values correlated with cardiac output during hemorrhage and reinfusion of the shed blood. Initially, intestinal PsO2 values fell more quickly than did renal PsO2; the latter decreased by approximately half as much as intestinal PsO2 after 15 and 30 ml/kg of blood loss. After a 45-ml/kg blood loss, however, the decreases in intestinal and renal PsO2 values were not significantly different from each other. During the terminal stage, cardiac output declined progressively, as did intestinal and renal PsO2 values, despite a relatively high PaO2. Overall, intestinal and renal PsO2 values tracked PaO2 during hypoxia, cardiac output during hemorrhage and reinfusion, and oxygen delivery during both conditions. Clinical and experimental experience indicates that organ PsO2 monitoring is potentially valuable for the intraoperative assessment of tissue perfusion and viability.

Animals