Focused Assessment with Sonography for Trauma (FAST): results from an international consensus conference

OBJECTIVE

To assemble an international panel of experts to develop consensus recommendations on selected important issues on the use of ultrasonography (US) in trauma care.

SETTING

R Adams Cowley Shock Trauma Center, University of Maryland Medical System, Baltimore, Md. The conference was held on December 4, 1997.

PARTICIPANTS

A committee of two co-directors and eight faculty members, in the disciplines of surgery and emergency medicine, representing four nations. Each faculty member had made significant contributions to the current understanding of US in trauma.

RESULTS

Six broad topics felt to be controversial or to have wide variation in practice were discussed using the ad hoc process: (1) US nomenclature and technique; (2) US for organ-specific injury; (3) US scoring systems; (4) the meaning of positive and negative US studies; (5) US credentialing issues; and (6) future applications of US. Consensus recommendations were made when unanimous agreement was reached. Majority viewpoints and minority opinions are presented for unresolved issues.

CONCLUSION

The consensus conference process fostered an international sharing of ideas. Continued communication is needed to advance the science and technology of US in trauma care.

Neuropeptide levels early after trauma: immunomodulatory effects?

The levels of endogenous opioids, beta-endorphin and methionine-enkephalin, were analyzed in 21 severely traumatized patients (ISS 32, mortality 42.8%) from a first blood sample drawn at the scene of the injury before resuscitation within 32 +/- 16 minutes after the injury and for 8 days after trauma. Additionally, the respiratory burst function of polymorphonuclear neutrophils (PMNs) was assessed and the results were compared with those obtained from 5 healthy control patients undergoing elective surgery with the same analgesic regimen as the multiple trauma patients. Compared with elective surgery anesthesia (controls 3.3, surgery 3.2 fmol/L), the beta-endorphin levels on-scene were markedly elevated (survivors 10.1 fmol/L, non-survivors 15.0 fmol/L) (p < 0.05). Methionine-enkephalin levels after trauma were not different from those of the controls. The stimulation of PMNs with different concentrations of the opioids at the first day after trauma gave results comparable with those of the controls. On the third day after trauma the reactivity of PMNs to low opioid concentrations was markedly suppressed to 79.6% of the baseline value (p < 0.05). Endogenous opioids seem to be able to modulate the nonspecific immune-response after trauma.

On-scene helicopter transport of patients with multiple injuries--comparison of a German and an American system

Hospital-based helicopter services from a German (GER) and an American (AMR) university-affiliated trauma center were reviewed. All patients with multiple injuries transported via helicopter from the scene to the trauma centers during a 1-year period were included. The patients were comparable regarding mechanism of injury, age, flight times, mean ISS, ISS distribution, and number of severe injuries per body region (patients with AIS score > 3 for head, thorax, and abdomen). Overall mortality was 21 of 221 (9.5%) for GER and 21 of 186 (11.3%) for AMR (NS). Survivor-based TRISS analysis yielded Z statistics of +2.459 for GER (p < 0.025) and +1.049 for AMR (NS). M statistics were 0.89 for GER, 0.874 for AMR; the W statistic +1.35 for GER. There were nine unexpected survivors (Ps < 0.50) for GER and six for AMR. There was a significantly higher (p < 0.01) number of early deaths (< 6 hours) in AMR (12; ISS = 56) than in GER (four; ISS = 64). Analysis of the prehospital data demonstrated significant differences in the mean volume of IV fluids infused: 1800 mL, GER; 825 mL, AMR (p < 0.05); rate of intubation: 82 of 221 (37.1%) GER; 24 of 186 (13.4%) AMR (p < 0.001); and thoracic decompressions: 20 of 221 (9.1%) GER; 1 of 186 (0.5%) AMR (p < 0.001). Prehospital care in the GER system is directed on scene by a trauma surgeon member of the flight crew compared with a nurse/paramedic team with remote medical control in the AMR system.(ABSTRACT TRUNCATED AT 250 WORDS)

Enhanced urinary excretion of leukotriene E4 by patients with multiple trauma with or without adult respiratory distress syndrome

1. The aim of the present study was to evaluate the systemic synthesis of cysteinyl leukotrienes in patients with multiple trauma. In order to do this, the urinary excretion of leukotriene E4 was assessed in the first 10 days after trauma. 2. Leukotriene E4 was unequivocally identified by g.c.-m.s. in the urine of healthy subjects and patients with multiple trauma after its conversion to 5-hydroxyeicosanoic acid. Leukotriene E4 was routinely isolated from 24 h urine samples by solid-phase extraction followed by reverse-phase h.p.l.c. and was subsequently quantified by r.i.a. 3. Healthy subjects excreted daily 10 +/- 3 nmol of leukotriene E4/mol of creatinine (mean +/- SEM, n = 16) into urine. 4. Patients with multiple trauma who did not develop adult respiratory distress syndrome (n = 7) excreted 76.8 +/- 6.7 nmol of leukotriene E4/mol of creatinine (mean +/- SEM) daily during the first 10 days after trauma, which was significantly (P less than 0.01) more than did healthy subjects. 5. Excretion of leukotriene E4 was even more enhanced in three patients with multiple trauma who developed adult respiratory distress syndrome. Maximal amounts of 593 +/- 185 nmol of leukotriene E4/mol of creatinine (mean +/- SEM) were excreted on day 9 after trauma by these three patients, which corresponds to a 7.7- and a 59-fold increase in excretion of leukotriene E4 compared with patients with multiple trauma who did not develop adult respiratory distress syndrome and healthy subjects, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Pathological fractures and lytic bone lesion of the femoral neck associated with beta 2-microglobulin amyloid deposition in long-term dialysis patients

A correlation is demonstrated between chronic hemodialysis using cuprophane membranes (mean duration: 13 years) and pathological fractures (n = 7 in 6 patients) after lytic bone deposits of beta 2-microglobulin amyloid (n = 13 patients). The characteristic symptom complex includes painful impingement syndrome of the shoulder, carpal tunnel syndrome, painful hip and recurrent knee effusions. The first steps of the clinical diagnostic procedure are to demonstrate lytic defects in skeletal radiographs and to verify the presence of beta 2m by biopsy or puncture. Due to reduced regeneration capacity in amyloid bone lesions the resulting surgical therapy should aim at total joint replacement or augmented osteo synthesis. Definitive operative treatment should be aspired even in the absence of manifest fractures, as the natural course of the disease is characterized by progression of the bone destruction and a continuous pain syndrome.

[Pathologic femoral neck fractures and para-articular beta 2 microglobulin amyloidosis in long-term dialysis patients: an increasingly frequent disease picture]

Beta-2-microglobulin (beta 2-M)-amyloidosis is caused by retention of beta 2-M by dialyzing membranes and by deposition as an atypical amyloid in synovia, bone and tendons. Ten patients under long-term hemodialysis (13 +/- 2.7 years) were treated because of hip pain and cystiform skeletal alterations. First typical joint affections appeared nine years after start of hemodialysis. Five fractures of the hip neck due to large cystiform bone lesions occurred in four subjects. In all cases a total joint replacement was performed.

[Humoral and cellular changes of non-specific immune response following severe trauma]

The influence of trauma and hemorrhagic shock on the non-specific immune system has been pointed out in various experimental studies. Other investigations have also been able to find a relationship between these changes and a higher incidence of post-traumatic complications in the form of organ failure. Our aim was to demonstrate the potential changes in the cellular defense system in a clinical study on multiple trauma patients. The polymorphonuclear leukocytes (PMNL) are the main representative of the mobile, non-specific immune system. Our study revealed a significant deterioration of PMNL function after trauma. The metabolic activity and phagocytic function were mainly affected by a decrease in the concentration of so-called "opsonins." The opsonins are important for the identification and engulfment of debris (necrosis, fat emboli and thrombi) and bacterial substances (endotoxin). Next to the opsonin level, a change in the receptor configuration is important for phagocytosis. However, we could not find any substantial evidence of surface receptor alteration. The reticuloendothelial cells (RES), a stationary phagocytic system, also showed a significant reduction in clearance function in these polytraumatized patients. Similar to PMNL, these disturbances were based on the reduction of the opsonine concentration. We were able to demonstrate a significant disturbance in immune function in multiple trauma patients with post-traumatic complications compared to patients with a normal clinical course after injury. Disturbances in the PMNL function (seen after 4 days) were found to appear after the RES disturbances. Systemic interaction between these two phagocytic systems cannot be excluded and further investigation is therefore required.

[Pathologic fractures in dialysis-associated amyloidosis]

A correlation could be demonstrated between four pathological femoral neck fractures in patients who regularly underwent hemodialysis; cystic bone deposits of beta-2-microglobulin amyloid were also found. The characteristic symptom complex includes painful arthralgia of the shoulder, carpal tunnel syndrome, pain in the hip and recurrent knee effusions. The first step in the diagnostic procedure is to demonstrate cystic defects in skeletal radiographs. Then a biopsy of the cystic bone lesion is needed for histological verification of beta-2-microglobulin. The surgical treatment is total joint replacement or augmented composite osteosynthesis due to poor regeneration capacity in the amyloid bone lesion.

[The infected wound]

The therapy of infected wounds is based on the knowledge of the pathophysiology of infection and on early diagnosis. The development of an infection depends on the general condition of the patient, local factors like foreign body contamination and tissue necrosis and the pathogenicity of the bacteria. The diagnosis of a wound infection is made upon the classical symptoms dolor, rubor, calor, tumor and functio laesa and depends on continuous wound care and repeated clinical judgement. The differentiation between an abscess as encapsulated infection and a diffuse non localized phlegmonous inflammation has different therapeutic consequences as the surgical treatment of an abscess consists of incision and drainage whereas the excision of infected tissue is necessary in phlegmones. The wound revision is a special form of excision. The surgical debridement is the most effective part of the therapy. Excision of infected and necrotic tissue help the phagocytic cells in infection fighting and remove the ideal culture medium for bacteria. The use of antibiotics can be very helpful if stringent indications are applied. Additional therapeutic approaches like improvement of local oxygen supply and enhancement of phagocytic function of macrophages could support the surgical therapy of the infected wound.

[Wounds and wound treatment, prevention of tetanus]

The care principles of injuries base on founded knowledge about the phases of wound healing, the causes of wound healing disturbances and the development of wound infections. The wound care includes the judgement of injuries, the surgical wound treatment and the aftercare. The wound evaluation with four categories makes a different therapeutic approach possible. The primary union is aspired to all non-infected wounds by direct wound closure. Suspicious infected and infected wounds are treated open after adequate wound excision. A secondary suture with a delayed primary wound closure is possible when the inflammation symptoms are recurrent. Other important aspects of wound care are a correct wound dressing, wound control and the checking for tetanus prophylaxis.

Pattern of collagen types and molecular structure of collagen in acute post-traumatic pulmonary fibrosis

Analyses of collagen types and their amino acid structures have been made with lungs obtained from eight patients who died from the adult respiratory distress syndrome after non-pulmonary trauma. Collagen in lungs from patients with the adult respiratory distress syndrome was twice as soluble as that in control lungs (p less than 0.01). The proportion of type III collagen in the whole organ as well as in the pepsin solubilised fraction was slightly but significantly raised (net increase of about 5-10% type III collagen (p less than 0.05]. Both type I and type III collagen from the patients contained less hydroxylysine than collagen from control lungs. The alterations in tissue composition described here and observed in normal wound healing support the notion that acute post-traumatic pulmonary fibrosis resembles a wound healing process in the lungs.

Phagocytic function of polymorphonuclear leukocytes and the RES in endotoxemia

The reticuloendothelial system (RES) and the polymorphonuclear leukocytes (PMNs) are thought to play a major role in defense against sepsis. Disturbances in the function of these two phagocytic systems during a septic event is associated with the development of lung capillary injury. Endotoxemia is said to lead to similar changes. Our study examined the function of the RES and PMNs after bolus injection of endotoxin (2 micrograms/kg BW) in a standardized sheep model. For up to 24 hr after endotoxin, blood samples were drawn and PMN function was followed by chemiluminescence, chemotaxis, and adherence as well as the phagocytosis and killing of bacteria. RES function was determined by the blood clearance of a labeled Tc99 colloid. We found an increase of RES clearance directly after endotoxin. Chemotaxis, phagocytosis, and killing were reduced. Adherence was increased. Chemiluminescence peak maximum (CLPM), representing the metabolic activity of the PMNs, was initially increased but shortly thereafter showed a significant decline (at 1 hr: 0.52 +/- 0.13 X 10(6) cpm with P less than 0.05 compared to baseline). The chemiluminescence peak time (CLPT), a measure of membrane receptor function, was significantly reduced (10.0 +/- 2.2 min with P less than 0.001 compared to baseline). Endotoxin led to a reduction of intracellular PMN functions (phagocytosis, killing, CLPM) within 1 hr. Membrane localized functions (adherence, CLPT) were increased. The changes in PMN function might be the reason for the development of lung capillary injury, in spite of undisturbed RES clearance.

[Nuclear medicine diagnosis of pulmonary capillary protein leakage]

Pulmonary extravascular albumin extravasation in patients with adult respiratory distress syndrome can be quantified with radionuclide techniques. While imaging procedures with a computerized gamma camera will allow reproducible ROIs, this will be the main limitation in nonimaging measurements with small scintillation probes. Repeated positioning by one operator results in a mean spatial variation of position of about 2 cm and a variation in count rate of 25%. For the estimation of PCPL the small probes must be positioned under scintigraphic control. Under these conditions the results of both techniques are identical. The upper limit of normal was estimated to be 1 x E-5/sec. The standard deviation of abnormal measurements was about 10%. The pulmonary capillary protein leakage can be quantified by radionuclide techniques with good accuracy, using the combination of imaging and nonimaging techniques.

Biochemical changes in parenchymal lung tissue associated with posttraumatic respiratory failure

We analysed the composition of parenchymal lung tissue from eleven multiply injured patients who died of protracted respiratory failure after an accident and six normal lungs. Lung wet and dry weights, protein, DNA, RNA and collagen amounts were determined in the lungs. Concentrations per dry weight of all parameters revealed only minor changes. Since there was a marked, time-dependent increase in both wet and dry weight, total lung contents of all components showed highly significant increases with survival time. Protein and RNA contents were elevated linearly in all patients, whereas DNA and collagen increased only in patients surviving more than 2 weeks. No correlation existed between biochemical data and a morphological fibrosis score, while morphometrically estimated cellularity and DNA concentration agreed well. Our results provide evidence that the reparative process for lung injury associated with traumatic shock is a tissue remodelling involving all tissue components in the long run.

Release of amino-terminal procollagen peptides in paraquat-induced acute pulmonary fibrosis

Acute pulmonary fibrosis following intoxication with paraquat is characterized by increased collagen synthesis and deposition in the lungs. In the present study, a chronic lung lymph fistula preparation in sheep was used to investigate the changes in procollagen type III peptide level in the lung lymph in acute pulmonary distress associated with paraquat application. The procollagen type III peptide is supposed to be an indicator of the changing biosynthetic pattern of pulmonary collagen in lung fibrosis. All animals tested showed a progressive pulmonary distress following the application of paraquat characterized by increasing lymph flows and lymph protein flows which monitored the microvascular membrane damage. In parallel to these findings, procollagen peptide levels in the lymph fluid increased, even before manifest biochemically or histologically detectable pulmonary fibrosis occurred. The present results suggest that the release of procollagen type III peptides into lymph fluid is an early indicator of beginning fibrotic tissue disarrangement, even before completed pulmonary fibrosis can be detected by common tissue analysis.

Nuklearmedizinische Diagnostik des »Pulmonary Capillary Protein Leakage«

Bei dem progressiven posttraumatischen Lungenversagen (Adult Respiratory Distress Syndrome, ARDS) kommt es zu einer Zunahme des extravaskulären Proteingehaltes in der Lunge. Die Kinetik dieser Proteinverschiebung kann szintigraphisch erfaßt werden. Die Technik mit Kamera und Rechner ist aufwendig und für die Intensivstation weniger geeignet. Wir haben daher geprüft, ob mit Einzelsonden die Kinetik ebenso erfaßt werden kann wie mit der Kamera. Bei gleichen Regions of Interest ergeben sich identische Werte; Schwierigkeiten bereitet jedoch die Reproduzierbarkeit bei der Plazierung der Detektoren; hier ergaben sich Lageabweichungen von im Mittel 2 cm, die zu Veränderungen der gemessenen Zählraten von 25% führten. Die wiederholte Untersuchung mit Einzeldetektoren setzt die Plazierung unter Kamerasicht und anschließende sichere Fixierung voraus. Als obere Grenze bei Normalen fand sich ein slope von 1 × E-5/Sek. Bei fünf Patienten mit pathologischen Werten war die Reproduzierbarkeit gut: bei zehnmaliger Bestimmung betrug die Standardabweichung im Mittel 10%. Eine ausreichend genaue Bestimmung der Proteinkinetik scheint damit möglich, Verlaufskontrollen mit Einzelsonden durchführbar.