Fluid Resuscitation In Trauma Research Articles

Fluid resuscitation in trauma: What you need to know.

There have been numerous changes in resuscitation strategies for severely injured patients over the last several decades. Certain strategies, such as aggressive crystalloid resuscitation, have largely been abandoned because of the high incidence of complications and worsening of trauma-induced coagulopathy. Significant emphasis has been placed on restoring a normal coagulation profile with plasma or whole blood transfusion. In addition, the importance of the lethal consequences of trauma-induced coagulopathy, such as hyperfibrinolysis, has been easily recognized by the use of viscoelastic testing, and its treatment with tranexamic acid has been extensively studied. Furthermore, the critical role of early intravenous calcium administration, even before blood transfusion administration, has been emphasized. Other adjuncts, such as fibrinogen supplementation with fibrinogen concentrate or cryoprecipitate and prothrombin complex concentrate, are being studied and incorporated in some of the institutional massive transfusion protocols. Finally, balanced blood component transfusion (1:1:1 or 1:1:2) and whole blood have become commonplace in trauma centers in North America. This review provides a description of recent developments in resuscitation and a discussion of recent innovations and areas for future investigation.

Fluid Resuscitation in Trauma

Introduction: Trauma is a problem faced everyday in the emergency room of the hospital where the researcher works. The degree of trauma from the mildest to life threatening can be found in sufferers. The cause of death in trauma sufferers is hypovolemic shock due to bleeding. The amount of blood loss volume from the patient can be estimated by looking at the clinical signs of the patient. Literature Review: In the condition of tissue hypoperfusion, it will cause a chain process which will eventually lead to cell death. Hypoperfusion causes anaerobic metabolism, lactic acidosis (coagulopathy, enzyme dysfunction), Na-K pump malfunction (cellular swelling and cell death), there is hypothermia (increase of oxygen demand, coagulopathy). Hypoperfusion will cause a vicious circle, in which processes that aggravate one another will occur. With the administration of fluids (crystalloid, colloid, transfusion) will improve the hypoperfusion that occurs in the body. Conclusion: The management of hypovolemic shock due to bleeding requires an understanding of the physiology and pathophysiology that occurs due to bleeding. To get maximum results and improve outcome from sufferers, it needs solid team work. Treatment can be different depending on the conditions, equipment and facilities of the hospital / emergency room as well as the policies of each place.

Fluid therapy in trauma resuscitation : A review of changing practices.

Background: Haemorrhage is the leading preventable cause of post trauma death. Acute trauma resuscitation has evolved over the last decade. The ATLS guidance used since 2012 is being updated in 2018.Objectives : To search relevant representative literature over 6 years between 2012 and 2018 to gain an insight into changing concepts, practices and recent advances in acute trauma fluid resuscitation and provide a structured review of the topic.Search methods: A relevant MEDLINE search was undertaken to obtain a list of 1512 articles from which 107 were utilised to prepare this review.Selection criteria:1. Inclusion: Articles from human medicine relevant to fluid resuscitation in trauma published in English between January 2012 and January 2018. 2.Exclusion: Articles restricted to Brain, spinal trauma or cardiovascular trauma, post traumatic arrest patients, animal or human laboratory model studies and articles on septic, postoperative, obstetric patients and single case studies were excluded.Results: This review categorises the topic into various parts to explain the evolving understanding of fluid resuscitation, trauma induced coagulopathy and endotheliopathy of trauma. The strategies for acute fluid management like damage-controlled resuscitation, balanced and haemostatic resuscitation and massive transfusion protocol are explained. A detailed discussion is carried out regarding crystalloid, colloid and blood transfusion. Special consideration is given to specific age groups, combat casualties and prehospital trauma care.Conclusions: Fluid resuscitation in trauma is a complex and rapidly evolving subject. Massive transfusion protocols and principles of damage control are significant for patient outcome. Standard guidance like ATLS is relevant and important for training professionals to deliver systematic, high quality of trauma care. There is scope for local improvisation based on resources and need for more high-quality trials and frequent systematic reviews.Bangladesh Crit Care J March 2018; 6(1): 31-39

Permissive hypotension versus conventional resuscitation strategies in adult trauma patients with hemorrhagic shock: A systematic review and meta-analysis of randomized controlled trials.

Aggressive fluid resuscitation in trauma promotes deleterious effects such as clot disruption, dilutional coagulopathy and hypothermia. Animal studies suggest that permissive hypotension maintains appropriate organ perfusion, reduces bleeding and improves mortality. This review assesses the efficacy and safety of permissive hypotension in adult trauma patients with hemorrhagic shock. We searched the MEDLINE and EMBASE databases from inception to May 2017 for randomized controlled trials comparing permissive hypotension vs. conventional resuscitation following traumatic injury. We included preoperative and intraoperative resuscitation strategies. The primary outcome was 30-day or in-hospital mortality. Secondary outcomes included blood product utilization, estimated blood loss and in-hospital complications. Pooling was performed with a random-effects model. We screened 722 abstracts, from which five randomized trials evaluating 1,158 patients were included. Blood pressure targets in the intervention arms varied from systolic BP 50 mm Hg to 70 mm Hg or mean arterial pressure of 50 mm Hg or higher as compared to systolic BP 65 mm Hg to 100 mm Hg or mean arterial pressure of 65 or higher in the control arms. Two studies evaluated only patients with penetrating injury while the remaining three additionally included blunt injuries. Four trials suggested a survival benefit for 30-day or in-hospital mortality with hypotensive resuscitation, although three studies were insufficiently powered to find statistical significance. Studies were of poor to moderate quality due to poor protocol reporting and lack of blinding. The pooled odds ratio was 0.70 (95% confidence interval, 0.53-0.92), suggesting a survival benefit for permissive hypotension. Those patients received fewer blood products and had lesser estimated blood loss. Permissive hypotension may offer a survival benefit over conventional resuscitation for patients with hemorrhagic injury. It may additionally reduce blood loss and blood product utilization. However, the majority of studies were underpowered, thus reflecting a need for high quality, adequately powered trials. Systematic Review, level II.CRD42017070526.

Comparison of Warm Fluid and Cold Fluid Resuscitations During Uncontrolled Hemorrhagic Shock Model in Rats

This study was designed to compare the effects of resuscitation with cold and warm fluid on survival time, rate and volume of hemorrhage, hemodynamics, hypothermia, coagulopathy, acid-base balance, hematocrit, lactate, and base deficit during uncontrolled hemorrhagic shock (HS) model in rats. HS model was created with splenic vascular and parenchymal injury in 29 rats under ketamine and xylazine anesthesia. Thirty minutes after the hemorrhage, the rats were randomized to receive 14.5 mL/kg 0.9% sodium chloride solution at either 24ºC (Group 1; n=9) or 4ºC (Group 2; n=10) for 20 minutes. Groups 1 and 2 were compared with group that did not receive fluid (Group 3; n=10). Statistical data were represented as mean±SD. SPSS for Windows, Version 15.0 (SPSS, Inc., Chicago, IL, USA) software, Bonferroni-adjusted Mann-Whitney U test and Kaplan-Meier procedure were used to perform statistical data analysis. P value of ≤0.05 was considered statistically significant. Cold fluid resuscitation decreased survival time due to increased rate and volume of hemorrhage, acidosis, hypothermia, lactate, and base deficit and decreased blood pressure and hematocrit. There is a great need for further experimental and clinical trials on fluid resuscitation in trauma in order to define which fluid should be administered, temperature of the fluid, quantity to be delivered, and duration.

Association of high volumes of hydroxyethyl starch with acute kidney injury in elderly trauma patients

IntroductionInitial fluid resuscitation in trauma is still controversial. Hydroxyethyl starch (HES), a commonly used fluid for resuscitation in trauma patients, has potential nephrotoxic effects. Advancing age is a known risk factor for acute kidney injury (AKI) in trauma patients. Therefore, the objective of this study was to evaluate the impact of large volumes of HES 130/0.4 on renal function in trauma patients, with a particular focus on the significance of age. MethodsA retrospective review of all patients admitted to the Trauma Centre of the University Hospital Regensburg from September 1, 2007 to December 31, 2012 was performed. This investigation used data from the TraumaRegister of the German Trauma Society (DGU®), including preclinical data from the prehospital emergency physician's protocol, the patient data management system of the intensive care units and the anaesthesia protocols of the emergency room and the operating room. AKI was evaluated according to the risk, injury, failure, loss, or end-stage kidney disease (RIFLE) criteria. The rate of AKI and the rate of renal replacement therapy (RRT) were compared between patients who received<2000ml HES 130/0.4 during the first 24h (L-HES) after trauma and patients who received≥2000ml HES 130/0.4 during the first 24h (H-HES) after trauma. An additional sub analysis of patients older than 59 years of age was performed. ResultsA total of 260 patients were included. Although patients in the H-HES group showed a higher injury severity score, the incidence of AKI and RRT were comparable. Furthermore, the sub analysis of patients older than 59 years of age also demonstrated similar results regarding incidence of AKI and the rate of RRT. ConclusionsFluid resuscitation with more than 2000ml HES (130kD/0.4) during the first twenty four hours after trauma was not associated with an increased incidence of AKI or need for RRT in trauma patients compared to patients who were administered<2000ml HES (130kD/0.4). The analysis of patients older than 59 years of age did not demonstrate any difference in the incidence of AKI or the need for RRT.

Prehospital fluid resuscitation in hypotensive trauma patients: Do we need a tailored approach?

AimThe ideal strategy for prehospital intravenous fluid resuscitation in trauma remains unclear. Fluid resuscitation may reverse shock but aggravate bleeding by raising blood pressure and haemodilution. We examined the effect of prehospital i.v. fluid on the physiologic status and need for blood transfusion in hypotensive trauma patients after their arrival in the emergency department (ED). MethodsRetrospective analysis of trauma patients (n=941) with field hypotension presenting to a level 1 trauma centre. Regression models were used to investigate associations between prehospital fluid volumes and shock index and blood transfusion respectively in the emergency department and mortality at 24h. ResultsA 1L increase of prehospital i.v. fluid was associated with a 7% decrease of shock index in the emergency department (p<0.001). Volumes of 0.5–1L and 1–2L were associated with reduced likelihood of shock as compared to volumes of 0–0.5L: OR 0.61 (p=0.03) and OR 0.54 (p=0.02), respectively. Volumes of 1–2L were also associated with an increased likelihood of receiving blood transfusion in ED: OR 3.27 (p<0.001). Patients who had received volumes of >2L have a much greater likelihood of receiving blood transfusion in ED: OR 9.92 (p<0.001). Mortality at 24h was not associated with prehospital i.v. fluids. ConclusionIn hypotensive trauma patients, prehospital i.v. fluids were associated with a reduction of likelihood of shock upon arrival in ED. However, volumes of >1L were associated with a markedly increased likelihood of receiving blood transfusion in ED. Therefore, decision making regarding prehospital i.v. fluid resuscitation is critical and may need to be tailored to the individual situation. Further research is needed to clarify whether a causal relationship exists between prehospital i.v. fluid volume and blood transfusion. Also, prospective trials on prehospital i.v. fluid resuscitation strategies in specific patient subgroups (e.g. traumatic brain injury and concomitant haemorrhage) are warranted.

Optimal fluid resuscitation in trauma: type, timing, and total.

This review article explores the recent literature regarding the optimal type and amount of intravenous fluids for the trauma patient from the time of injury through their ICU stay. It discusses damage control principles as well as targeted resuscitation utilizing new technology. In the prehospital arena, intravenous fluids have been associated with worse patient outcomes due to increased coagulopathy and time to definitive care. Once in the trauma bay, damage control resuscitation principles apply to the severely injured patient. Large volume crystalloid infusion increases mortality. The best patient outcomes have been found with transfusion of blood products in a ratio that closely mimics whole blood. Thrombelastography is a useful adjunct in resuscitation and can help guide the judicious use of blood products. New technology can help providers ascertain when a patient is appropriately resuscitated by determining adequate global and regional perfusion. During the resuscitation of the acutely injured patient, crystalloids should be limited in favor of blood components. Damage control principles apply until definitive hemostasis is obtained, at which point the focus should change to targeted resuscitation using traditional global endpoints of resuscitation in conjunction with determinants of regional perfusion.

Fluid resuscitation in trauma and critical care : Current guidelines

Outcome data on fluid therapy in trauma and critically ill patients suggests a direct correlation between positive fluid balance and increased mortality. Randomised-controlled trials over the past decade comparing the effects of hydroxyethyl starch (HES) preparations and crystalloids for fluid resuscitation in critically illpatients have demonstrated an increased mortality and use of renal replacement therapy (RRT) associated with HES solutions. Balanced salt solutions have shown promise as initial resuscitation fluids, though there is not enough clinical data regarding their comparative safety and efficacy.

Clinical research priorities in emergency medicine

To determine the clinical research priorities of Fellows of the Australasian College for Emergency Medicine (ACEM) in order to inform the strategic research agenda specific to multicentre clinical research. An anonymous survey of all ACEM Fellows (FACEMs) listed on the ACEM researcher database was conducted between January and March 2013. Of 108 FACEMs invited to participate, 54 (50%) responded. Over half of respondents (61%) had a higher research degree but only a minority (24%) had funded research positions. The top research categories identified as priorities were resuscitation, trauma, cardiology, ED ultrasound, acute behavioural disturbance and geriatrics. The most common specific sub-categories included anterior chest pain, fluid resuscitation in trauma, and drug therapy for both atrial fibrillation and acute behavioural disturbance. Several specific research questions related to chest pain, resuscitation/sepsis, stroke, paediatrics and pulmonary embolus. The findings provide guidance and support for research areas amenable to collaborative multicentre clinical research within emergency medicine. Discussion rounds are planned to translate these perceived research priorities to actual priorities.

Fluid Resuscitation in Trauma.

Fluid Resuscitation in Trauma.

Hypotensive resuscitation

Hypotensive resuscitation in the trauma setting can be defined as deliberately allowing blood pressure to remain below normal until any active bleeding has been controlled. The dangers of aggressive fluid resuscitation in trauma were recognised as long ago as the First World War, in the intervening time, aggressive fluid resuscitation has become a mainstay of trauma management. More recently this trend of aggressive fluid resuscitation for trauma management seems to be reversing. Aggressive fluid resuscitation in trauma is based on animal studies from the 1950s and 1960s. These studies used models of controlled haemorrhage rather than uncontrolled haemorrhage. More recent studies using models of uncontrolled haemorrhage suggest an improved outcome with hypotensive resuscitation. Should there be a potential for uncontrolled haemorrhage a permissive hypotensive resuscitation strategy should be pursued until the haemorrhage has been controlled, but in certain types of trauma including blunt trauma and brain trauma the data is unclear as to the best fluid resuscitation strategy.

Fluid therapy for the traumatized patient

AbstractObjective:To review the rationale behind and experiences with traditional and newly evolving concepts of fluid therapy in the traumatized patient, and to review conventional and novel fluid preparations for use in trauma resuscitation.Data sources:Human and veterinary clinical and research studies.Human data synthesis:Current treatment guidelines recommend aggressive fluid resuscitation with lactated ringers solution (LRS) or saline as optimum management of hemorrhagic shock in trauma, regardless of whether bleeding is controlled or not. The rationale behind this strategy is to restore intravascular volume as rapidly as possible to ensure adequate vital organ perfusion. Recently, this strategy has been challenged, especially in patients with uncontrolled hemorrhage, as neither laboratory evidence nor clinical trials support this practice. Current research indicates that vigorous fluid infusion may exacerbate bleeding and cause severe hemodilution, both impairing resuscitation outcome. As a result, a new line of thinking is emerging that balances the risks and benefits of intravenous volume infusion by offering the clinician alternative treatment strategies and emphasizes continuous endpoint‐oriented monitoring. ‘Hypotensive’ or ‘hypovolemic’ resuscitation techniques as well as initial volume replacement with fluids other than LRS or saline (e.g., hypertonic saline [HTS], HTS with dextran 70 [HTS‐D]) have been introduced in human medical practice as additional options for treatment of victims of trauma under certain circumstances. Clinical studies evaluating the use of hemoglobin‐based oxygen carriers (HBOCs) in the trauma setting are underway and may soon lead to an expansion of the fluid arsenal available to the clinician for treatment of trauma patients.Veterinary data synthesis:Based on available animal data, neither strict guidelines nor a clear fluid preference for resuscitation of traumatic shock have been defined. Although systematic clinical trials are missing, combinations of crystalloid and colloid (natural or artificial) appear to be as effective for resuscitation as crystalloid alone. Judicious use of an HBOC (e.g., Oxyglobin®) as a substitute for blood/red blood cells may be recommended in situations where whole blood or pRBCs are not or not yet available.Conclusions:The search for optimal methods of fluid resuscitation in trauma is ongoing. At this point the best solution is a differentiated approach to fluid therapy, one that tailors type and volume of resuscitation solution(s) used to the type and severity of injury in an individual patient and uses monitoring of perfusion and oxygenation parameters to guide resuscitation. Crystalloid fluids are effective for resuscitation but may need to be combined with or replaced by colloidal fluids in certain clinical situations.

Fluid resuscitation in trauma

Appropriate fluid replacement is an essential component of trauma fluid resuscitation. Once hemorrhage is controlled, restoration of normovolemia is a priority. In the presence of uncontrolled haemorrhage, aggressive fluid management may be harmful. The crystalloid-colloid debate continues but existing clinical practice is more likely to reflect local biases rather than evidence based medicine. Colloids vary substantially in their pharmacology and pharmacokinetics,and the experimental finding based on one colloid cannot be extrapolated reliably to another. In the initial stages of trauma resuscitation the precise fluid used is probably not important as long as an appropriate volume is given. Later, when the microcirculation is 'leaky', there may be some advantages to high or medium weight colloids such as hydroxyethyl starch. Hypertonic saline solutions may have some benefit in patients with head injuries. A number of hemoglobin solutions are under development, but one of the most promising of these has been withdrawn recently. It is highly likely that at least one of these solutions will eventually become routine therapy for trauma patient resuscitation. In the meantime, contrary to traditional teaching, recent data suggest that restrictive strategy of red cell transfusion may improve outcome in some critically ill patients.

Current development and use of hemoglobin‐based oxygen‐carrying (HBOC) solutions

AbstractObjective: To review the human and veterinary literature on the current development and use of hemoglobin‐based oxygen‐carrying solutions.Human data synthesis: Hemoglobin‐based oxygen‐carrying (HBOC) solutions have been developed extensively over the last 3 decades. Early problems associated with pure hemoglobin and cytoskeleton residues have been resolved with chemical modification of the hemoglobin tetramer resulting in effective oxygen‐carrying molecules of either human or bovine origin. The limited availability of human red blood cells and concerns of disease transmission, the difficulty in mass production of genetically produced hemoglobin solutions (recombinant hemoglobin), and the wide availability of bovine blood have resulted in the development of bovine‐derived HBOC solutions. Research efforts have been directed toward determining the effects of HBOC solutions on tissue perfusion as the target uses of HBOC solutions in human medicine are the perioperative period, shock, and trauma fluid resuscitation. The most controversial issues regarding the cardiovascular effects of HBOC solutions surround increased vasoactivity. Some HBOC formulations have been removed from advanced clinical trials due to intense vasoactivity resulting in increased morbidity. There are currently 3 HBOC solutions in the latter stages of phase III clinical trials: Hemolink®,a Hemopure®,b and PolyHeme®.c The hemoglobin source of Hemopure® is bovine, and the hemoglobin source for Hemolink® and Polyheme® is human.Veterinary data synthesis: The only HBOC solution that has gained approval from the FDA is the veterinary product Oxyglobin®.d Oxyglobin® is 13 g/dL of ultrapurified, polymerized hemoglobin solution of bovine origin in a modified lactated Ringer's solution. There is a significant colloid effect and it also provides a plasma source of oxygen‐carrying capacity. The solution is stable at room temperature for 3 years; there is no special preparation required prior to use and no cross‐match is required prior to administration (contains no cell membranes). Veterinary publications on the use of Oxyglobin® include laboratory investigations in dogs, cats, and horses for use as a resuscitation fluid and for the treatment of anemia. Clinical use of Oxyglobin® in dogs, cats, birds, horses, and other mammalian species has been reported in several publications.Conclusion: The search for a safe, effective HBOC solution for use in human medicine is ongoing. Soon, there will be one or several products approved for use in the perioperative period and/or for the treatment of shock and trauma. The practice of veterinary emergency and critical care has been provided a unique opportunity to apply the use of an HBOC solution (Oxyglobin®) to various aspects of perfusion and oxygen‐carrying needs. Continued clinical experience and research is essential in understanding the use of HBOC solutions in veterinary medicine.

Trauma fluid resuscitation in 2010.

Trauma fluid resuscitation in 2010.

VASCULAR ACCESS AND FLUID RESUSCITATION IN TRAUMA: Issues of Blood and Blood Products

For the past 2 decades, resuscitation after major trauma has included intravenous (IV) infusions of isotonic fluids. The hemodynamic response to the initial fluid bolus provides information on the amount and type of additional fluid needed. Patients who become hemodynamically stable and do not seem to have ongoing blood loss may continue to be treated with crystalloid IV infusions, together with close monitoring of urine output and hemodynamic parameters. Patients who are not hemodynamically stable or who seem to have ongoing blood loss may require transfusion of erythrocytes and other blood products. The decision to transfuse homologous blood or blood components requires consideration of the complications associated with transfusion therapy, including transfusion reactions, transfusion-transmitted disease, and transfusion-induced immunomodulation. The solitary use of a specific hemoglobin level as a transfusion trigger should be avoided. Before transfusing blood or blood products to trauma patients, consideration should be given to the patients' oxygen delivery and oxygen consumption. Oxygen delivery is a function of both cardiac output and arterial oxygen content. Arterial oxygen content is a function of hemoglobin oxygen saturation, hemoglobin concentration, and the amount of oxygen physically dissolved in arterial blood: 22 CaO 2 = (SaO 2 /100) × (1.39 + Hgb) + (0.03 + PaO 2 ) where CaO 2 is the arterial oxygen content, SaO 2 is the hemoglobin oxygen saturation, Hgb is the hemoglobin concentration, and PaO 2 is the arterial oxygen pressure. The effects of hypovolemia must be separated from those of anemia and oxygen transport. The effect of the initial fluid bolus and the need for subsequent fluid therapy helps to identify hypovolemic patients. Table 1 shows the four classes of shock as defined by the American College of Surgeons Committee on Trauma. Experience has shown that patients who lose up to 30% of their blood volume (class I or II) can usually be treated adequately with crystalloid infusion. A loss of more than 30% total blood volume (class III or IV) generally requires the addition of blood to the replacement fluid. 1 In a retrospective study of 1000 patients, Knottenbelt 13 demonstrated a correlation between low initial hemoglobin levels and mortality in trauma patients. Although it is traditionally taught that it takes hours for the body to respond to blood loss by moving fluid into the capillary circulation from interstitial spaces, Knottenbelt's data suggest that patients who present with low initial hemoglobin may have suffered significant hemorrhage that has resulted in autotransfusion. Extracellular fluid is drawn into a capillary (autotransfusion) when the plasma oncotic pressure exceeds the capillary hydrostatic pressure. This readily occurs in trauma patients with excessive blood loss and severe hypotension. Knottenbelt's study also concluded that finding low hemoglobin on presentation after injury indicates severe and ongoing blood loss, and the anemia is not caused by the dilutional effect of the initial fluid bolus. Therefore, the effect of autotransfusion has important implications in clinically assessing blood loss. This article reviews the use of blood and blood components in trauma patients, the appropriate use of blood component therapy, complications of transfusion therapy, and complications of massive transfusion. Blood component therapy is supportive rather than primarily therapeutic, even with regard to hemostasis. Thus, four major reasons exist for transfusion blood or its components into the hemorrhaging patient: (1) improvement of systemic oxygen transport; (2) restoration of critical red cell mass; (3) correction of bleeding caused by dilutional thrombocytopenia, platelet dysfunction, or pathologic platelet consumption; and (4) correction of bleeding caused by a factor deficiency or pathologic consumption of coagulation proteins.

Timing of Fluid Resuscitation in Trauma

The resuscitation of hypotensive patients with hypovolemia who have sustained penetrating injuries traditionally follows the management principles outlined in the American College of Surgeons Advanced Trauma Life Support course.1 These principles consist of the establishment of a patent airway, ventilation with oxygen, and fluid resuscitation with crystalloid and colloid solutions. The goal is to establish adequate perfusion of cerebral and myocardial tissue with well-oxygenated blood.Conventional treatment at the scene of the event includes airway and oxygen management followed by rapid transportation to a trauma center.2 No time should be wasted gaining intravenous access, but fluid resuscitation can be established . . .

KBSIM/FLUIDTHERAPY: a system for optimized design of fluid resuscitation in trauma

An application of the kbsim (Knowledge-Based SIMulation) system to the improved design of fluid resuscitation is described. The system integrates knowledge from three domains, viz. the pathophysiology of traumatized patients represented in a quantitative biodynamic model, the heuristics of fluid resuscitation of such patients as represented in ‘production rules’, and some ‘metaknowledge’ reflected in the design of a multi-window user interface. This technique of combining numerical simulation with symbolic reasoning has obvious advantages during the design process and in training, by giving the user a possibility to evaluate his measures by direct feedback from the system. This feature of the system to assist in evaluation of alternative resuscitation procedures should also be useful as a means for decision support.

Computer simulation of fluid resuscitation in trauma. First pragmatic validation in thermal injury.

A comprehensive pathophysiologic model has been designed to describe the fluid shifts and hemodynamics in connection with fluid therapy for patients who have had trauma. The model is used to simulate treatment of a patient with burn injury, and these results are compared with measured physiologic and biochemical variables. Various formulas for resuscitation of patients with thermal injuries are also simulated to illustrate the potential use of the "patient simulator" for designing fluid resuscitation programs.