Rational or rationalized choices in fluid resuscitation?

The war between colloids and crystalloids wages on. In a large multinational survey of fluid prescribing practices in critically ill patients, we have a new and intriguing snapshot of global fluid resuscitation practices. Colloids are more often used for impaired perfusion or low cardiac output, and the choice of colloid or crystalloid varies enormously between countries. Why are some ICUs prescribing colloids more often than crystalloids when there is little convincing evidence that colloids are superior for fluid resuscitation? Are colloids advantageous in certain diseases, or in specific regional patient populations that have not yet been elucidated? Perhaps we should look inwards: the answer may not be more randomized clinical trials, but better adherence to current guidelines and treatment recommendations.     

延迟复苏治疗活动性失血性休克临床探讨

目的：探讨延迟复苏策略治疗重症活动性失血性休克在临床的应用实践。方法：延迟复苏组（A组）,限制输晶体液和胶体液量,扩容更多地依赖输血及血浆,控制目标血压以收缩压80~90 mm Hg（1 mm Hg=0.133 kPa）为允许性低血压;传统复苏组（B组）,不限制输晶体液和胶体液量,快速进行液体复苏。输液以晶体液和胶体液为主,输血及血浆为辅助,不有意控制血压上限。结果：A组抢救成活率显著高于B组。结论：在重症加强护理病房（ICU）临床上认识重症活动性失血性休克特殊性以及治疗的特殊性。应用延迟复苏方法,有望提高该类危重患者的治愈率。     

Review of a fluid resuscitation protocol: "fluid creep" is not due to nursing error

Recent reviews of burn resuscitation have included the suggestion that "fluid creep" may be influenced by practitioner error. Our center uses a nursing-driven resuscitation protocol that permits titration of fluid based on hourly urine output, including the addition of colloid when patients fail to respond appropriately. The purpose of this study was to examine protocol compliance. We reviewed 140 patients (26 children) with burns of ≥20% TBSA who received protocol-directed resuscitation from 2005 to 2010. We compared each patient's actual hourly fluid infusion with that predicted by the protocol. Sixty-seven patients (48%) completed resuscitation using crystalloid alone, whereas 73 patients required colloid supplementation. Groups did not differ in age, gender, weight, or time from injury to admission. Patients requiring colloid had larger median total burns (33.0 vs 23.5% TBSA) and full-thickness burns (15.5 vs 4.5% TBSA) and more inhalation injuries (60.3 vs 28.4%; P < .001) than those who resuscitated with crystalloid alone. Because we included basic maintenance fluids in their regimen, patients had median predicted requirements of 5.4 ml/kg/%TBSA. Crystalloid-only patients required fluid volumes close to Parkland predictions (4.7 ml/kg/%TBSA), whereas patients who received colloid required more fluid than the predicted volume (7.5 ml/kg/%TBSA). However, the hourly difference between the predicted and received fluids was a median of only 1.0% (interquartile range: -6.1 to 11.1%) and did not differ between groups. Pediatric patients had greater calculated differences than adults. Crystalloid patients exhibited higher urine outputs than colloid patients until colloid was started, suggesting that early over-resuscitation did not contribute to fluid creep. Adherence to our protocol for burn shock resuscitation was excellent overall. Fluid creep exhibited by more seriously injured patients was not due to nurses' failure to follow the protocol. This review has illuminated some opportunities for practice improvement, possibly using a computerized decision support system.     

Review article: Prehospital fluid management in traumatic brain injury

The early management of patients who have sustained traumatic brain injury is aimed at preventing secondary brain injury through avoidance of cerebral hypoxia and hypoperfusion. Especially in hypotensive patients, it has been postulated that hypertonic crystalloids and colloids might support mean arterial pressure more effectively by expanding intravascular volume without causing problematic cerebral oedema. We conducted a systematic review to investigate if hypertonic saline or colloids result in better outcomes than isotonic crystalloid solutions, as well as to determine the safety of minimal volume resuscitation, or delayed versus immediate fluid resuscitation during prehospital care for patients with traumatic brain injury. We identified nine randomized controlled trials and one cohort study examined the effects of hypertonic solutions (with or without colloid added) for prehospital fluid resuscitation. None has reported better survival and functional outcomes over the use of isotonic crystalloids. The only trial of restrictive resuscitation strategies was underpowered to demonstrate its safety compared with aggressive early fluid resuscitation in head injured patients, and maintenance of cerebral perfusion remains the top priority.     

An Argument for Colloid Resuscitation for Shock

A focused review of the physiologic mechanisms of colloid and crystalloid fluid resuscitations for acute critical illness is presented. This review suggests that postresuscitation plasma volume, cardiac output, left ventricular mechanical performance, and global and microcirculatory O₂ supplies are more favorable with colloid therapy. Conversely, crystalloid may adversely affect microcirculatory blood flow and resultant O₂ supply and use by ischemic tissues in shock. Poor relief of global and regional hypoxia may persist in critically ill patients after resuscitation with crystalloid.     

Fluid resuscitation of hypovolemia

Conclusions A great deal has been learned about fluid resuscitation in the last several decades. The choice of an appropriate fluid for resuscitation in every given clinical situation has not yet been definitively determined but we can make some conclusions based on currently available data. It should again be emphasized that the goal of resuscitation of hypovolemic shock is quite clear regardless of the choice of fluid; to resuscitate the shock state as quickly as possible while at the same time minimizing the deleterious effects of fluid resuscitation on the pulmonary, renal, immunological and other systems.Animal experimental work reveals that use of colloid solutions to minimize pulmonary edema formation is ineffective, especially in instances where pulmonary capillary permeability is increased. Further, there are suggestions that colloid solutions may actually exacerbate pulmonary dysfunction following resuscitation by changing the characteristics of the pulmonary interstitium and the dynamics of fluid flux in the lung. This is entirely consistent with Starling's theory of a balance of hydrostatic and osmotic pressure, given what we now understand about the other or interstitial side of the Starling equation.Aside from the lungs, there are known side effects of various colloid solutions on other organs and body systems. In addition, questions remain about other possible associated short-term and long-term renal, coagulation, and immunological effects.Clinical studies using extravascular lung water as an objective parameter of pulmonary dysfunction show no correlation with fluid balance and no deleterious effects of crystalloid resuscitation.The relative cost of various resuscitation fluids should be a minor point when making therapeutic decisions. These relative costs, however, argue strongly for crystalloid therapy unless advantages for colloid fluids can be proved. Such proof is lacking to date.This is not to say that colloid solutions might never be called for. An occasional situation may arise in which sudden acute hypovolemia is associated with difficulties in obtaining good intravenous access. An example would be the victim of an automobile accident trapped for a prolonged period in a vehicle. Such situations impose practical limits on the amount of volume that can be infused. The use of colloid solutions to provide maximal intravascular volume restoration may be justified in such instances. In the vast majority of cases of hypovolemia, however, the balance of experimental, clinical, and practical considerations convincingly favor the use of a crystalloid solution for resuscitation in association with blood and clotting factors as needed.     

Resuscitation in shock associated with burns. Tradition or evidence-based medicine?

OBJECTIVE: To summarize the present standards and guidelines for fluid treatment of shock associated with burns, and to evaluate their scientific support in the literature. DESIGN: Nonsystematic, critical review of the literature regarding the indications for crystalloid and colloid fluid treatment, invasive monitoring and the use of resuscitation end points in shock associated with burns. SUMMARY POINTS: Crystalloid fluid resuscitation of patients with burns is traditionally managed using empirical resuscitation formulae, with the efficacy monitored by vital signs and urinary output The value of these end points has been questioned by recent studies, which have suggested that such noninvasive parameters may be inadequate for detecting malperfusion. No consensus exists regarding appropriate assessment of adequate resuscitation, and the impact on survival of invasive measures has still to be proven in controlled randomized trials. Generally, a significantly higher fluid requirement has been demonstrated when resuscitation is based on invasive cardiorespiratory monitoring. Colloid resuscitation in burns patients is controversial. Published reports suggest that colloid infusion should be started between 6 and 36 h following thermal injury. A recent meta-analysis highlighted the shortcomings of albumin in patients with burns, and this, together with restrictions for the use of plasma products, has obscured the choice of colloid solution. The effect of colloid resuscitation on survival remains to be proven in burned patients. CONCLUSION: The current standards for monitoring fluid therapy in patients with large burns are not supported by scientific data. Further randomized, controlled trials are indicated, and should help establish general guidelines regarding monitoring and treatment end points in these patients.     

Colloids vs crystalloids

The choice of colloid or crystalloid solutions for resuscitation of a patient in shock remains controversial. Colloids quickly restore plasma volume along with stabilizing hemodynamics. Almost the entire volume is retained within the vascular space after 1 hour. However, only 8 percent of infused water and less than 25 percent of infused saline are retained in intravascular fluid compartments after 1 hour. When using crystalloids for resuscitation, two to four times as much fluid is required for fluid repletion. The very young or old or persons with cardiac or renal dysfunction may have an increased risk of developing pulmonary edema when crystalloids are administered.     

CONTRA: Hydroxyethyl starch solutions are unsafe in critically ill patients

Purpose  To describe the risk–benefit profile of hydroxyethyl starch (HES). Methods  Narrative review. Results  (1) Efficacy: no single clinical study or systemic review has shown that administration of any HES solution confers a clinically relevant benefit compared to crystalloids in critically ill patients or surgical patients in need of volume replacement. Contrary to beliefs expecting a ratio of 4:1 or more for crystalloid to colloid volume need, recent studies of goal-directed resuscitation observed much lower ratios of between 1 and 1.6. (2) Safety: HES administration is associated with coagulopathy, nephrotoxicity, pruritus and increased long-term mortality. Clinical studies claiming that modern HES 130/0.4 is safe have serious methodological drawbacks and do not adequately address the safety concerns. Conclusions  Given the complete lack of superiority in clinical utility studies and the wide spectrum of severe side effects, the use of HES in the ICU should be stopped. The belief that four times as much crystalloid as colloid fluid volume is needed for successful resuscitation is being seriously questioned. C. Hartog and K. Reinhart contributed equally to this work. The article arguing for this proposition is available at: doi:.     

The effects of commonly used resuscitation fluids on whole blood coagulation

Objectives

Evidence on the effect of crystalloid and colloid resuscitation fluids on coagulation is confusing, with contradictory results from previous studies. This study was performed to test the effect on whole blood coagulation of a range of resuscitation fluids in vitro using a single method at a single dilution.

Methods

Seven resuscitation fluids were tested in vitro at a dilution of 40%. Whole blood coagulation was measured using a Sonoclot analyser.

Results

A crystalloid/colloid split of effect on coagulation in vitro was not seen. The time to clot formation with Gelofusine, dextran and hydroxyethyl starch was a greatly increased, whereas saline and Haemaccel had little effect, or were slightly procoagulant.

Conclusions

Some resuscitation fluids have a profound effect on coagulation. The confusion in the literature may result from the effect on coagulation being both fluid and dilution dependent, with no simple crystalloid/colloid split.     

Fluid resuscitation in children

Children most often need fluid resuscitation because of fluid loss (especially from diarrhoea), while bleeding and sepsis account for a minority of cases. The child's immature body systems (especially cardiovascular and renal), age-dependent fluid compartment sizes and lack of degenerative vascular diseases of adulthood affect the child's clinical signs and the response to hypovolaemia and to resuscitation. The issues of what fluid, how much, how fast and by what route are interdependent. In general, aggressive early fluid resuscitation reduces mortality and morbidity in children with burns and sepsis, while slow rehydration over 48 hours is safer in dehydrated children with diarrhoea or diabetic ketoacidosis. There are few specifically paediatric data comparing hyper- or isotonic crystalloid with colloid, or the various colloids with each other, so that legends abound in paediatric resuscitation. The empirical basis of these legends will be discussed in this paper. Safe resuscitation requires close observation of the cardiovascular system, conscious state, urine output and blood chemistry. When close biochemical monitoring is not possible, a fluid regime should be chosen which is least likely to cause biochemical changes.     

Systemic complications of fluid resuscitation.

Fluid administration in critically ill individuals is frequently a major component of their therapy. There are important effects on blood pressure and maintenance of cardiac output and oxygen delivery, as detailed elsewhere in this text. There are also potentially negative side effects of this therapy, which have been less well defined. Edema of the gastrointestinal tract has been well described, primarily with crystalloid infusions. Gastrointestinal edema may have very complicated effects on albumin kinetics, fluid flux, and ion flux. It may lead to development of ileus. Increased nasogastric tube output may be incorrectly construed as unremitting obstruction rather than a result of the aforementioned changes and increased crystalloid loads. The relationships of intestinal edema to intestinal absorptive function and diarrhea are less clear. At present, changes in type of fluid infusion or correction of serum albumin level to normal cannot be uniformly recommended. The myocardium, although showing evidence of edema with crystalloid infusion, may appear to benefit from colloidal, osmotically active suspensions in the all too few studies that have been done. To date, there is no study giving evidence of clinically different outcome using a variety of fluids that cause, reduce, or prevent this edema. The presence or absence of myocardial edema may be important in patients who demonstrate decreased ventricular function during sepsis or other disorders in which aggressive fluid administration is routine. Edema of the skin has been associated primarily with decreased oxygen tension. Other studies have shown an association with impaired wound healing or increased risk of infection. A direct causal relationship can only be inferred. We are left with a sense that aggressive fluid resuscitation with crystalloid, although improving oxygen delivery, may have other deleterious effects on organ systems, such as the gastrointestinal tract, myocardium, and integument. The edema resulting from crystalloid administration may lessen or negate the benefits of increased oxygen delivery. Care needs to be taken in interpreting any alteration in organ function with respect to the fluid type and volume being administered. An alternative choice of therapy is lacking at present. The role of colloid has not been as well investigated as that of crystalloid and further study is warranted before any benefits become clear.     

The capacity of different infusion fluids to lower the prooxidant activity of plasma iron: an important factor in resuscitation?

BACKGROUND: Prooxidant activity of non-protein-bound iron (NPBI) is an important contributor to reactive oxygen species-induced injury after the resuscitation of critically ill patients. Plasma NPBI occurs in critically ill adults, children, and newborn babies, who often require resuscitation. The ability of the resuscitation fluids to bind iron and lower the patients' NPBI levels in vitro has not previously been studied. STUDY DESIGN AND METHODS: In an in vitro model, highly iron-saturated cord blood plasma from 10 preterm and 10 term babies was mixed with FFP, pasteurized plasma protein solution, and 0.9-percent saline. Plasma from 10 healthy adult volunteers was used as a control. Before and after the mixing with any resuscitation fluid, NPBI levels and ceruloplasmin iron-oxidizing and transferrin iron-binding antioxidant capacities were measured. RESULTS: After the in vitro mixing with FFP, the incidence and concentration of NPBI were markedly decreased and the iron-binding antioxidant capacity was increased in the plasma of the preterm and term babies. Being mixed with pasteurized plasma protein solution and 0.9-percent saline did not influence the iron-binding antioxidant capacity of newborn babies' plasma. In the control plasma, results were not changed after the mixing with any resuscitation fluid. In every group, the iron-oxidizing antioxidant capacity was not changed after the mixing with any fluid. CONCLUSION: Iron-induced oxidative tissue damage may be influenced by resuscitation fluids. In the ongoing debate over the choice of crystalloid or colloid resuscitation fluids, the influence of each fluid on the patient's antioxidant capacity warrants more attention.     

Albumin in critical care: SAFE,but worth its salt?

Intravascular fluid therapy is a common critical care intervention. However, the optimal type of resuscitation fluid, crystalloid or colloid, remains controversial. Despite the many theoretical benefits of human albumin administration in critically ill patients, there has been little evidence to support its widespread clinical use. Previous systematic reviews have led to conflicting results regarding the safety and efficacy of albumin. The recently reported Saline versus Albumin Evaluation study has provided conclusive evidence that 4% albumin is as safe as saline for resuscitation, although no overall benefit of albumin use was seen. Subgroup analysis of the albumin-treated group revealed a trend towards decreased mortality in patients with septic shock, and a trend towards increased mortality in trauma patients, especially those with traumatic brain injury. The results of these subgroups, as well as the use of higher albumin concentrations and other synthetic colloids (dextrans, starches), require rigorous evaluation in clinical trials. Finally, the Saline versus Albumin Evaluation trial represents a methodological milestone in critical care medicine, due to its size, its efficient trial design, and its logistical coordination. Future studies are still required, however, to establish a therapeutic niche for albumin and other colloids.     

The appropriate role of colloids in managing fluid imbalance: a critical review of recent meta-analytic findings

Three meta-analyses have recently been reported on the relationship between choice of resuscitation fluid and risk of mortality in critically ill patients. The relative risk of death (1.16-1.19) in two of the meta-analyses was slightly higher in colloid than crystalloid recipients; however, this observation was not statistically significant. In the third meta-analysis, 6% (95% confidence interval [CI], 3-9%) pooled excess mortality was documented in patients receiving albumin for hypovolaemia, burns or hypoalbuminaemia. The mortality difference in hypovolaemia patients (4%; 95% CI, 0-8%) was not statistically significant. A variety of serious limitations apply to the three meta-analyses, suggesting that their findings be interpreted cautiously. More than one-half of the randomized controlled trials (RCTs) included in the meta-analyses were reported prior to 1990 and hence do not reflect current practice. Each meta-analysis included only a subset of relevant RCTs, and therefore the scope of inferences to be drawn from the meta-analytic results is limited. The meta-analyses combined RCTs that were notably heterogeneous with respect to patient characteristics, type of illness, administered fluids and physiologic endpoints. Differences in illness severity, concomitant therapies and fluid management approaches were not taken into account. Very few of the RCTs were blinded. The meta-analyses do not support the conclusion that choice of resuscitation fluid is a major determinant of mortality in critically ill patients, nor do they support changes to current fluid management practice. Changes such as exclusive reliance on crystalloids would necessitate a reassessment of the goals and methods of fluid therapy. Since the effect on mortality may be minimal or non-existent, choice of resuscitation fluid should rest on whether the particular fluid permits the intensive care unit to provide better patient care.     

An international comparison of the cost of fluid resuscitation therapies

ObjectiveFluid resuscitation is a ubiquitous intervention in the management of patients treated in the intensive care unit, which has implications for intensive care unit resourcing and budgets. Our objective was to calculate the relative cost of resuscitation fluids in several countries to inform future economic evaluations.MethodsWe collected site-level data regarding the availability and cost of fluids as part of an international survey. We normalised costs to net present values using purchasing power parities and published inflation figures. Costs were also adjusted for equi-effective dosing based on intravascular volume expansion effectiveness and expressed as US dollars (USD) per 100 mL crystalloid equivalent.ResultsA total of 187 sites had access to cost data. Between countries, there was an approximate six fold variation in the cost of crystalloids and colloids overall. The average cost for crystalloids overall was less than 1 USD per 100 mL. In contrast, colloid fluids had higher average costs (59 USD per 100 mL). After adjusting for equi-effective dosing, saline was ～27 times less costly than albumin (saline: 0.6 USD per 100 mL crystalloid equivalent; albumin 4–5%: 16.4 USD; albumin 20–25%: 15.8 USD) and ～4 times less costly than hydroxyethyl starch solution (saline: 0.6 USD; hydroxyethyl starch solution: 2.5 USD). Buffered salt solutions, such as compound sodium acetate solutions (e.g., Plasmalyte®), had the highest average cost of crystalloid fluids, costing between 3 and 4 USD per 100 mL.ConclusionThe cost of fluid varies substantially between fluid types and between countries, although normal (0.9%) saline is consistently less costly than colloid preparations and some buffered salt solutions. These data can be used to inform future economic evaluations of fluid preparations.     

Massive transfusion protocols for patients with substantial hemorrhage

Transfusion medicine for the resuscitation of patients with massive hemorrhage has recently advanced from reactive, supportive treatment with crystalloid and red blood cell therapy to use of standardized massive transfusion protocols (MTPs). Through MTPs, medical facilities are able to standardize the most effective posthemorrhage treatments and execute them rapidly while reducing potential waste of blood products. Damage control resuscitation is an example of an MTP, where patients are (1) allowed more permissive hypotension, (2) spared large volumes of crystalloid/colloid therapy (through low volume resuscitation), and (3) transfused with blood products preemptively using a balanced ratio of plasma and platelets to red blood cells. This focused approach improves the timely availability of blood components during resuscitation. However, the use of MTPs remains controversial. This review describes published experiences with MTPs and illustrates the potential value of several MTPs currently utilized by academic transfusion services.     

Fluid resuscitation in neonatal and pediatric hypovolemic shock: a Dutch Pediatric Society evidence-based clinical practice guideline

Objective To develop a clinical practice guideline that provides recommendations for the fluid, i.e. colloid or crystalloid, used for resuscitation in critically ill neonates and children up to the age of 18 years with hypovolemia.Methods The guideline was developed through a comprehensive search and analysis of the pediatric literature. Recommendations were formulated by a national multidisciplinary committee involving all stakeholders in neonatal and pediatric intensive care and were based on research evidence from the literature and, in areas where the evidence was insufficient or lacking, on consensus after discussions in the committee.Results Because of the lack of evidence in neonates and children, trials conducted in adults were considered. We found several recent meta-analyses that show excess mortality in albumin-treated groups, compared with crystalloid-treated groups, and one recent large randomized controlled trial that found evidence of no mortality difference. We found no evidence that synthetic colloids are superior to crystalloid solutions.Conclusions Given the state of the evidence and taking all other considerations into account, the guideline-developing group and the multidisciplinary committee recommend that in neonates and children with hypovolemia the first-choice fluid for resuscitation should be isotonic saline.The work was funded by the ‘Practice Guidelines Program’ at the Academic Medical Centre in Amsterdam. This article is discussed in the editorial available at:     

Studies in shock and resuscitation, I: use of a hypertonic, albumin-containing, fluid demand regimen (HALFD) in resuscitation.

We have reevaluated and clinically tested the current concepts of shock and resuscitation on a logical, physiological, and physical basis. We have considered the currently accepted resuscitation paradigm which is based upon the thesis that early rapid resuscitation of "lost" fluid volume is mandatory and that adequacy of resuscitation can be evaluated by central venous pressure, PAP, PAWP, pulse rate, blood pressure, and/or urine volume. Such methods also accept as natural concomitants that capillary beds are "damaged by injury"; that they "leak" salt, fluid, and albumin; and that these are expected occurrences which are injury-related. We have also examined and clinically evaluated the thesis that MAP is a primary reflector of the relationships between volume and the size of the currently available functional vascular space. (Currently available functional vascular space is mediated through the baroreceptor (stretch receptor)/neuroendocrine mechanisms.) Under this hypothesis, fluid resuscitation comprises infusion of a volume per unit time given so as to replete currently measurable fluid losses and to normalize and/or sustain MAP and the normal osmolar and oncotic relationships at the capillary/tissue interface while holding hydrostatic pressure at normal. Using burn injury as a model, we compared statistically homogeneous, randomly selected groups of burn patients who were resuscitated using a hypotonic fluid (130 mOsm/liter) alone (group R: 7 patients), hypertonic fluid (240 mOsm/liter) alone group H: 5 patients), or the hypertonic fluid containing albumin (12.5 g/liter) (group A: 7 patients). The results indicate that significantly smaller volumes of fluid were needed to resuscitate the patients in group A with a significantly more rapid normalization of physical, physiological, and biochemical parameters. We conclude that the physically and physiologically appropriate method of resuscitation, demonstrated in burn injury, comprises the use of a fluid given at a rate: (1) to maintain mean arterial and hydrostatic pressures within normal range; (2) that delivers a volume per unit time which does not exceed the capacity of the currently available functional vascular space; (3) that replaces concurrent measurable fluid losses; (4) that is hypertonic (to normalize capillary/tissue osmotic gradients); and (5) that contains colloid (to normalize capillary/tissue osmotic gradients); and (5) that contains colloid (to normalize capillary/tissue oncotic gradients). We further conclude that salt, fluid, and colloid loss into the interstitium during resuscitation frequently is due to the rate delivered and/or the physical nature of the fluid used and not to capillary bed damage outside the zone of injury.     

Influences on physicians' choices of intravenous colloids

OBJECTIVES: Controversy over the optimal intravenous fluid for volume resuscitation continues unabated. Our objectives were to characterize the demographics of physicians who prescribe intravenous colloids and determine factors that enter into their decision to choose a colloid. DESIGN: Questionnaire with 61 items. PARTICIPANTS AND SETTING: Ten percent ( n = 364) of frequent intravenous fluid prescribers in the province of Ontario, Canada. RESULTS: The response rate was 74%. Colloid use in the past year was reported by 79% of the responding physicians. Important reasons for choosing a colloid included blood loss and manipulation of oncotic pressure. Physicians tended to prefer either albumin or pentastarch, but no important reasons were found for choosing between the two. Albumin with or without crystalloid was preferred in 5/13 scenarios by more than 50% of the respondents, whereas pentastarch was not favored by more than 50% of respondents in any scenario. Physicians practising in critical care areas and teaching hospitals generally preferred pentastarch to albumin. Physicians reporting pentastarch as representing greater than 90% of total colloid use were more likely to have been visited by a drug detailer for pentastarch than those who used less synthetic colloid (54 vs 22%, p < 0.001).CONCLUSIONS: The majority of physicians surveyed prescribe colloid products and the reported use of albumin and pentastarch has a bimodal distribution. Although albumin appeared to be preferred in more clinical niches, most physicians did not state reasons for choosing between products. Marketing, specialty, location of practice and clinical scenario appear to play significant roles in the utilization of colloid products.