Cardiac magnetic resonance, transthoracic and transoesophageal echocardiography: a comparison of in vivo assessment of ventricular function in rats.

In vivo assessment of ventricular function in rodents has largely been restricted to transthoracic echocardiography (TTE). However 1.5 T cardiac magnetic resonance (CMR) and transoesophageal echocardiography (TOE) have emerged as possible alternatives. Yet, to date, no study has systematically assessed these three imaging modalities in determining ejection fraction (EF) in rats. Twenty rats underwent imaging four weeks after surgically-induced myocardial infarction. CMR was performed on a 1.5 T scanner, TTE was conducted using a 9.2 MHz transducer and TOE was performed with a 10 MHz intracardiac echo catheter. Correlation between the three techniques for EF determination and analysis reproducibility was assessed. Moderate-strong correlation was observed between the three modalities; the greatest between CMR and TOE (intraclass correlation coefficient (ICC) = 0.89), followed by TOE and TTE (ICC = 0.70) and CMR and TTE (ICC = 0.63). Intra- and inter-observer variations were excellent with CMR (ICC = 0.99 and 0.98 respectively), very good with TTE (0.90 and 0.89) and TOE (0.87 and 0.84). Each modality is a viable option for evaluating ventricular function in rats, however the high image quality and excellent reproducibility of CMR offers distinct advantages even at 1.5 T with conventional coils and software.

Quality assessment of intraoperative blood salvage and autotransfusion.

Intraoperative blood salvage and autotransfusion are commonly used to minimize exposure to banked blood. Although this technique has been used widely for years, data vary regarding the quality of autotransfused blood. Salvaged blood may contain plasma, residual heparin, and free hemoglobin released from damaged cells. All of these factors may contribute to the adverse sequelae sometimes seen with autotransfusion. For these reasons, we have monitored autotransfused blood to assess its quality. Intraoperative blood salvage was used during most cardiac procedures and at the discretion of the surgeon in other specialties. Blood was collected through a double lumen catheter that was anticoagulated with heparin, filtered, centrifuged, and washed with saline. A sample of the blood was removed for analysis, which included hematocrit, heparin assay, fibrinogen, and free hemoglobin levels. Over a 6-year period, 1593 patients had intraoperative blood salvage with quality assessment. The majority of patients underwent cardiac operations (941 patients, 59%), whereas 243 had orthopedic (15%) and 208 had vascular (13%) procedures. Additionally, there were 127 pediatric patients (8%) and 74 miscellaneous procedures (5%). The highest average yield of salvaged blood was during vascular procedures (1073 +/- 76 mL), whereas orthopedic cases had the lowest yield (378 +/- 19 mL) and hematocrit (39%). There was minimal residual heparin activity, even in patients requiring systemic anticoagulation (0.3 to 0.5 units/mL). Patients undergoing pediatric procedures had the lowest concentration of free hemoglobin (476 mg/L), whereas all adult patients had higher free hemoglobin levels, especially vascular operations (990 mg/L). Intraoperative salvaged blood has minimal heparin activity, even in procedures requiring systemic anticoagulation. Fibrinogen, a marker of residual plasma, was undetectable in the majority of cases. These data indicate that intraoperative blood salvage generally results in a high-quality product (good hematocrit, low heparin, minimal plasma), although there are significant differences in free hemoglobin levels depending on the operative procedure.

Percutaneous dilational tracheostomy for airway control.

BACKGROUND: Endoscopic percutaneous dilational tracheostomy (PDT) is a good alternative to obtain safe and secure long-term airway control, and is associated with minimal morbidity and mortality. STUDY DESIGN: During a 14-month period, we prospectively studied 35 intensive care unit (ICU) trauma patients who underwent early PDT for the sole purpose of obtaining long-term airway control. All patients were determined to need a tracheostomy owing to extubation inability, need to maintain a patent airway, or need for continuous airway access for management of secretions. RESULTS: All patients had sustained multiple injuries with an average Injury Severity Score (ISS) of 29. The time from ICU admission to placement of the PDT was 8 +/- 5 days. The mean Glasgow Coma Scale at the time of the PDT was 10 (range 4 to 15), and 11 patients (31%) had an intracranial pressure device in place. The procedure was completed with bronchoscopic guidance in 33 patients, and in 2 it was converted to surgical tracheostomy (ST). There were no significant complications associated with the placement of the PDT. Two deaths were documented, neither related to the PDT placement. Compared with standard ST, charges were reduced by $1,750. CONCLUSIONS: Bedside endoscopic PDT for selected critically ill trauma patients is justified as a safe and effective alternative to ST. The low incidence of complications in PDT suggests that it can be done safely at bedside in the ICU.

Venous thromboembolism in the high-risk trauma patient: do risks justify aggressive screening and prophylaxis?

OBJECTIVE: Deep venous thrombosis (DVT) and pulmonary embolism (PE) are considered to be a major source of morbidity and mortality among trauma patients. Several reports have identified high-risk patients with recommendations for management ranging from frequent duplex scanning to placement of prophylactic inferior vena cava (IVC) filters. We reviewed our experience with a large trauma population to determine whether such approaches are justified. METHODS: We analyzed 2,868 consecutive trauma admissions over 22 months and identified 280 patients (10%) in high-risk groups who survived > or = 48 hours: (1) severe closed head injury with mechanical ventilation > or = 72 hours, (2) closed head injury with lower extremity fractures, (3) spinal column/cord injury, (4) combined pelvic and lower extremity fractures, and (5) major infrarenal venous injuries. The remaining nonthermal injury patients constituted the low-risk group. RESULTS: There were 280 high-risk patients, 213 of whom (76%) received prophylaxis with compression therapy. There were 12 cases of DVT (5%) with four nonfatal PE (1.4%). Six patients (2%) had therapeutic IVC filters inserted and only one patient had prophylactic placement. There were 38 deaths in this group, attributable primarily to severe closed head injury or spine injuries, and none were caused by PE. In the 2,249 low-risk patients, there were three cases of DVT (0.1%, p < 0.05 vs. high risk) and no PE (p < 0.05 vs. high risk). CONCLUSIONS: Although these patients were at increased risk for thromboembolic events, the overall incidence of DVT was still extremely low with no apparent PE deaths. In our patient population, aggressive screening and prophylactic IVC filters would not have benefited 95% of "high-risk" patients without DVT and would not have prevented any deaths. We could not identify any population, except perhaps venous injuries, where such expensive and potentially harmful maneuvers seemed justified. Our experience with DVT and PE does not support either aggressive screening or prophylactic IVC filters as the standards of care.

After the shooting stops: follow-up on victims of an assault rifle attack.

OBJECTIVE: To determine long-term medical, social, and psychological outcome of survivors of a multiple-shooting mass casualty disaster. DESIGN: A case-study review was performed 42 months after injury involving chart reviews and patient interviews. PARTICIPANTS: Survivors of a multiple shooting. MAIN OUTCOME MEASURES: The need for primary operative treatment, subsequent operations, and medical treatment related to the injuries, current work status, and psychological impact of injury was determined. RESULTS: Thirteen patients required operation initially; 12 are long-term survivors. Eight have returned to work. Most of the victims reported experiencing psychological and emotional problems. CONCLUSIONS: Despite a well-functioning trauma system that maximized survival from devastating injury, considerable long-term morbidity and disability persists. Efforts at prevention of mass casualties seem to be the only potential solution.

The economic status of trauma centers on the eve of health care reform.

An in-depth understanding of the economic problems confronting trauma centers is essential for their continued development and to address impending changes of health care reform. A comprehensive financial and demographic survey was sent to 839 hospitals identified as potential trauma centers. A total of 313 surveys from 48 states were returned. Extensive information was collected in several areas including financial status (58% reported serious financial problems and 36% reported minor financial problems; 68% reported a financial loss), cost containment and management strategies, marketing, "halo" effect (53% reported positive effect), operational impacts, physician support (47% reported problems), malpractice (92% reported no special problem), role of auto insurance reimbursement, and access to rehabilitation. Detailed financial data of actual costs and reimbursements (95 respondents) were analyzed with the costing method used by the Health Care Financing Administration (HCFA). These data will allow us to develop better strategies to deal with the problems of uncompensated and underfunded trauma care and improve trauma center viability.

An analysis of the critical problem of trauma center reimbursement.

There is a widespread perception that many trauma centers are poorly reimbursed, and many hospitals that once cared for trauma victims no longer do so, primarily for financial reasons. The problem is blamed on both uninsured and underinsured patients, but data supporting this perception are lacking. To determine the validity of these perceptions and to better understand the nature of trauma center reimbursement, a survey was conducted. A questionnaire on the volume of trauma seen annually and the reimbursement experience for trauma center (TC) and hospital (HO) patient populations was mailed to representative but nonrandomly chosen trauma centers. Seventy-one surveys were mailed and 25 were returned (35%). There were 15 Level I and 10 Level II centers; 16 were urban, seven were suburban, and two were rural. Eighteen centers (72%) reported significant underfunding of the TC in contrast to the HO, and 11 indicated that they would not be able to continue their current level of TC services with present reimbursement. For Medicare patients, HO cost recovery rates averaged 93%, but recovery rates were only 64% for TCs. For Medicaid beneficiaries, the HO cost recovery rate averaged 85%, but it was only 49% for TCs. Thirty-one percent of TC patients had no insurance coverage at all, in contrast to only 9% of HO patients. An aggregate loss equal to 19.9% of total costs was reported by respondents. This survey, while not representative of trauma centers as a whole throughout the United States, does suggest that there is a basis for the perception of underfunding of trauma care and indicates that such underfunding results from the combination of adverse selection and disproportionate share. We also describe a new method for assessing and comparing trauma center reimbursement.

Institutionally shared trauma rotations are viable solutions to deficiencies in trauma training.

Numerous national trauma leaders have expressed concern about the lack of uniformity of trauma training in this country. In 1984 we instituted a trauma rotation between the University of Louisville (U.L.), with a large trauma volume, and Loyola University (L.U.) in the planning stages of trauma center development. Third year L.U. residents rotated at U.L. in 3-month blocks with an increased level of responsibility monthly, culminating in major decision-making roles and operative treatment under the chief resident's direction. The L.U. residents functioned as full members of the team and not as passive observers. Fifteen L.U. residents and 12 U.L. residents rotated during this period. Yearly major trauma visits, helicopter flights, and trauma service admissions average 1,908, 700, and 1,520, respectively. U.L. chief residents averaged 136 major operative trauma cases and 115 nonoperative trauma cases each were managed during this time period (RRC records greater than 85th percentile for all U.L. residents). L.U. residents performed an average of 30 major operative cases, nine as teaching assistant, in 3 months. Each managed more than 75 nonoperative cases. Several elements are critical in such a multi-institutional rotation: 1) active communication among the program directors, 2) commitment to one sharing arrangement only, 3) financing and malpractice for off-site residents, 4) housing, and 5) the ability to assimilate off-site residents as true trauma team members. The resident-to-resident interplay is crucial and has succeeded because both residency staffs have had excellent early training.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of trauma assessment scores and their use in prediction of infection and death.

Current trauma assessment scores do not include an assessment of immune competence and have not been designed to predict late death from or risk of infection. We have compared the use of the Outcome Predictive Score (OPS) with other standard scales to predict clinical outcome after trauma. The OPS combines the Injury Severity Score (ISS) corrected for age (%LD50), degree of bacterial contamination, and monocyte HLA-DR antigen expression on hospital admission. The OPS was compared to the ISS, %LD50, Revised Trauma Score (RTS), Combined Trauma Score-ISS (TRISS), and Anatomical Index (AI). Sixty-one seriously ill patients were studied. Patient outcome was defined as uneventful recovery (n = 18), major infection (n = 27), and death (13 of 16 deaths resulted from infection). The assessment scores were compared for their use in prediction of these outcomes, as well as their ability to distinguish patients with good outcome from those patients who developed major infection or died, and to differentiate survival from death. Only the OPS was able to significantly segregate all five outcome groups (p less than 0.05). Although the age-adjusted ISS distinguished between survival and death (p less than 0.05), only OPS consistently distinguished between good outcome and sepsis/death (p less than 0.05), and therefore best identified the patients who developed infection. AI, RTS, and TRISS had little predictive value.

Life after general surgery residency: subsequent practice patterns of chief residents.

No recent reports characterize the practice patterns of graduates of current general surgical residency programs. The University of Louisville Department of Surgery surveyed recent graduates of our program who were established in practice, to determine whether the training they had received had adequately prepared them for their subsequent positions. Ninety percent of our graduates responded to a questionnaire. More than 80% of residents still regularly performed general surgical procedures even though more than 38% had completed some additional fellowship training. More than 75% of our graduates were satisfied with their income. The vast majority were satisfied with their work load and their training. Although more data are needed to determine how practice patterns develop, no current evidence suggests that current training practices are inadequate or wasteful.