Con: Starches Are Not Preferable to Albumin During Cardiac Surgery: A Contrary Opinion

Colloids versus crystalloids for fluid resuscitation in critically ill patients

BACKGROUND

Colloid solutions are widely used in fluid resuscitation of critically ill patients. There are several choices of colloid, and there is ongoing debate about the relative effectiveness of colloids compared to crystalloid fluids.

OBJECTIVES

To assess the effects of colloids compared to crystalloids for fluid resuscitation in critically ill patients.

SEARCH METHODS

We searched the Cochrane Injuries Group Specialised Register (17 October 2012), the Cochrane Central Register of Controlled Trials (The Cochrane Library) (Issue 10, 2012), MEDLINE (Ovid) 1946 to October 2012, EMBASE (Ovid) 1980 to October 2012, ISI Web of Science: Science Citation Index Expanded (1970 to October 2012), ISI Web of Science: Conference Proceedings Citation Index-Science (1990 to October 2012), PubMed (October 2012), www.clinical trials.gov and www.controlled-trials.com. We also searched the bibliographies of relevant studies and review articles.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of colloids compared to crystalloids, in patients requiring volume replacement. We excluded cross-over trials and trials involving pregnant women and neonates.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and rated quality of allocation concealment. We analysed trials with a 'double-intervention', such as those comparing colloid in hypertonic crystalloid to isotonic crystalloid, separately. We stratified the analysis according to colloid type and quality of allocation concealment.

MAIN RESULTS

We identified 78 eligible trials; 70 of these presented mortality data.COLLOIDS COMPARED TO CRYSTALLOIDS: Albumin or plasma protein fraction - 24 trials reported data on mortality, including a total of 9920 patients. The pooled risk ratio (RR) from these trials was 1.01 (95% confidence interval (CI) 0.93 to 1.10). When we excluded the trial with poor-quality allocation concealment, pooled RR was 1.00 (95% CI 0.92 to 1.09). Hydroxyethyl starch - 25 trials compared hydroxyethyl starch with crystalloids and included 9147 patients. The pooled RR was 1.10 (95% CI 1.02 to 1.19). Modified gelatin - 11 trials compared modified gelatin with crystalloid and included 506 patients. The pooled RR was 0.91 (95% CI 0.49 to 1.72). (When the trials by Boldt et al were removed from the three preceding analyses, the results were unchanged.) Dextran - nine trials compared dextran with a crystalloid and included 834 patients. The pooled RR was 1.24 (95% CI 0.94 to 1.65). COLLOIDS IN HYPERTONIC CRYSTALLOID COMPARED TO ISOTONIC CRYSTALLOID: Nine trials compared dextran in hypertonic crystalloid with isotonic crystalloid, including 1985 randomised participants. Pooled RR for mortality was 0.91 (95% CI 0.71 to 1.06).

AUTHORS' CONCLUSIONS

There is no evidence from randomised controlled trials that resuscitation with colloids reduces the risk of death, compared to resuscitation with crystalloids, in patients with trauma, burns or following surgery. Furthermore, the use of hydroxyethyl starch might increase mortality. As colloids are not associated with an improvement in survival and are considerably more expensive than crystalloids, it is hard to see how their continued use in clinical practice can be justified.

Colloids versus crystalloids for fluid resuscitation in critically ill patients

BACKGROUND

Colloid solutions are widely used in fluid resuscitation of critically ill patients. There are several choices of colloid and there is ongoing debate about the relative effectiveness of colloids compared to crystalloid fluids.

OBJECTIVES

To assess the effects of colloids compared to crystalloids for fluid resuscitation in critically ill patients.

SEARCH METHODS

We searched the Cochrane Injuries Group Specialised Register (searched 16 March 2012), Cochrane Central Register of Controlled Trials 2011, issue 3 (The Cochrane Library), MEDLINE (Ovid) 1946 to March 2012, Embase (Ovid) 1980 to March 2012, ISI Web of Science: Science Citation Index Expanded (1970 to March 2012), ISI Web of Science: Conference Proceedings Citation Index-Science (1990 to March 2012), PubMed (searched 16 March 2012), www.clinical trials.gov and www.controlled-trials.com. We also searched the bibliographies of relevant studies and review articles.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of colloids compared to crystalloids, in patients requiring volume replacement. We excluded cross-over trials and trials in pregnant women and neonates.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data and rated quality of allocation concealment. We analysed trials with a 'double-intervention', such as those comparing colloid in hypertonic crystalloid to isotonic crystalloid, separately. We stratified the analysis according to colloid type and quality of allocation concealment.

MAIN RESULTS

We identified 74 eligible trials; 66 of these presented mortality data.Colloids compared to crystalloids Albumin or plasma protein fraction - 24 trials reported data on mortality, including a total of 9920 patients. The pooled relative risk (RR) from these trials was 1.01 (95% confidence interval (CI) 0.93 to 1.10). When we excluded the trial with poor quality allocation concealment, pooled RR was 1.00 (95% CI 0.92 to 1.09). Hydroxyethyl starch - 21 trials compared hydroxyethyl starch with crystalloids, n = 1385 patients. The pooled RR was 1.10 (95% CI 0.91 to 1.32). Modified gelatin - 11 trials compared modified gelatin with crystalloid, n = 506 patients. The pooled RR was 0.91 (95% CI 0.49 to 1.72). (When the trials by Boldt et al were removed from the three preceding analyses, the results were unchanged.) Dextran - nine trials compared dextran with a crystalloid, n = 834 patients. The pooled RR was 1.24 (95% CI 0.94 to 1.65).Colloids in hypertonic crystalloid compared to isotonic crystalloid Nine trials compared dextran in hypertonic crystalloid with isotonic crystalloid, including 1985 randomised participants. Pooled RR was 0.91 (95% CI 0.71 to 1.06).

AUTHORS' CONCLUSIONS

There is no evidence from RCTs that resuscitation with colloids reduces the risk of death, compared to resuscitation with crystalloids, in patients with trauma, burns or following surgery. As colloids are not associated with an improvement in survival, and as they are more expensive than crystalloids, it is hard to see how their continued use in these patients can be justified outside the context of RCTs.

Colloids versus crystalloids for fluid resuscitation in critically ill patients

BACKGROUND

Colloid solutions are widely used in fluid resuscitation of critically ill patients. There are several choices of colloid and there is ongoing debate about the relative effectiveness of colloids compared to crystalloid fluids.

OBJECTIVES

To assess the effects of colloids compared to crystalloids for fluid resuscitation in critically ill patients.

SEARCH STRATEGY

We searched the Cochrane Injuries Group Specialised Register, CENTRAL (The Cochrane Library 2008, Issue 3), MEDLINE, EMBASE, ISI Web of Science: Science Citation Index Expanded (SCI-EXPANDED), ISI Web of Science: Conference Proceedings Citation Index-Science (CPCI-S), and The Controlled Trials metaRegister (www.controlled-trials.com). Reference lists of relevant studies and review articles were searched for further trials. The searches were last updated in September 2008.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of colloids compared to crystalloids, in patients requiring volume replacement. We excluded cross-over trials and trials in pregnant women and neonates.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data and rated quality of allocation concealment. We analysed trials with a 'double-intervention', such as those comparing colloid in hypertonic crystalloid to isotonic crystalloid, separately. We stratified the analysis according to colloid type and quality of allocation concealment.

MAIN RESULTS

We identified 65 eligible trials; 56 of these presented mortality data.Colloids compared to crystalloidsAlbumin or plasma protein fraction - 23 trials reported data on mortality, including a total of 7754 patients. The pooled relative risk (RR) from these trials was 1.01 (95% confidence interval (95% CI) 0.92 to 1.10). When we excluded the trial with poor quality allocation concealment, pooled RR was 1.00 (95% CI 0.91 to 1.09). Hydroxyethyl starch - 17 trials compared hydroxyethyl starch with crystalloids, n = 1172 patients. The pooled RR was 1.18 (95% CI 0.96 to 1.44). Modified gelatin - 11 trials compared modified gelatin with crystalloid, n = 506 patients. The pooled RR was 0.91 (95% CI 0.49 to 1.72). (When the trials by Boldt et al were removed from the three preceding analyses, the results were unchanged.) Dextran - nine trials compared dextran with a crystalloid, n = 834 patients. The pooled RR was 1.24 (95% CI 0.94 to 1.65).Colloids in hypertonic crystalloid compared to isotonic crystalloidEight trials compared dextran in hypertonic crystalloid with isotonic crystalloid, including 1283 randomised participants. Pooled RR was 0.88 (95% CI 0.74 to 1.05).

AUTHORS' CONCLUSIONS

There is no evidence from RCTs that resuscitation with colloids reduces the risk of death, compared to resuscitation with crystalloids, in patients with trauma, burns or following surgery. As colloids are not associated with an improvement in survival, and as they are more expensive than crystalloids, it is hard to see how their continued use in these patients can be justified outside the context of RCTs.

[Guidelines on therapy with blood components and plasma derivatives: human albumin. Recommendations of the scientific advisory board of the Medical Council]

Human albumin (HA) is by far the most expensive option for volume replacement and correction of hypoalbuminemia but is still widely used. The value of HA in the clinical setting continues to be controversial and it remains unclear whether there is still a place for using such a high-priced substance in the present cost-consciousness climate. Thus the Medical Council has presented some recommendations with regard to blood and plasma products including HA. There appear to be no indications for HA to correct hypovolemia either perioperatively or in the intensive care setting including children and patients undergoing cardiac or liver surgery. For maintaining colloid oncotic pressure (COP) cheaper modern synthetic colloids can be alternatively given and the value of HA for correcting hypoalbuminemia is also not clearly justified. Some small uncontrolled studies have shown that only patients with liver cirrhosis, spontaneous bacterial peritonitis and massive ascites drainage may profit from HA. Theoretical benefits such as oxygen radical scavenging or binding of toxic substances are no indications for using HA as beneficial clinical consequences have not yet been demonstrated. Experimental data from cell lines or animals must be viewed with skepticism because they do not mimic the clinical setting. According to the recommendations of the scientific advisory board of the Medical Council the use of HA should be considered very cautiously.

Use of albumin: an update

Human albumin (HA) is widely used for volume replacement or correction of hypoalbuminaemia. The value of HA in the clinical setting continues to be controversial, and it is unclear whether in today's climate of cost consciousness, there is still a place for such a highly priced substance. It is therefore appropriate to update our knowledge of the value of HA. With the exception of women in early pregnancy, there appears to be few indications for the use of HA to correct hypovolaemia. Some studies of traumatic brain injury and intensive care patients suggest negative effects on outcome and organ function of (hyperoncotic) HA. Modern synthetic colloids appear to be a cheaper alternative for maintaining colloid oncotic pressure. The value of using HA to correct hypoalbuminaemia has not been clearly justified. Theoretical and pharmacological benefits of HA, such as oxygen radical scavenging or binding of toxic substances, have not as yet been shown to have beneficial clinical consequences. Experimental data from cell lines or animals do not appear to mimic the clinical setting. Convincing data justifying the use of HA either for treating hypovolaemia or for correcting hypoalbuminaemia are still lacking. A restricted use of HA is recommended.

Rationale for albumin infusions

PURPOSE OF REVIEW

To describe the metabolism and function of albumin, and to scrutinize the evidence that infusion of albumin may be beneficial in disease. To explain why albumin infusion does not improve clinical outcome in most disease states, studied.

RECENT FINDINGS

Albumin acts as a binding protein and an oncotic agent. However, albumin may also act as an extracellular scavenger, which leads to oxidation of albumin. It is likely that this compromises its function and it is possible that this drives its degradation. In disease, these useful processes are accelerated leading to rapid ageing of the molecule.Albumin infusion does not improve clinical outcome despite increasing oncotic pressure in chronic disease. It is not superior to nonprotein colloids or electrolyte solutions in acute hypovolemia with one or two exceptions (liver failure, possibly cerebral infarction). One potential explanation is that pharmaceutical albumin does not have the oxidative qualities that freshly synthesized albumin has.

SUMMARY

Albumin infusion has not proven to achieve clinical benefit in many acute and chronic disease states with a few exceptions in acute hypovolemia (e.g. postparacentesis). Future studies should reveal whether infusion of freshly synthesized nonoxidized albumin is of greater clinical benefit.

Colloids versus crystalloids for fluid resuscitation in critically ill patients

BACKGROUND

Colloid solutions are widely used in fluid resuscitation of critically ill patients. There are several choices of colloid and there is ongoing debate about the relative effectiveness of colloids compared to crystalloid fluids.

OBJECTIVES

To assess the effects of colloids compared to crystalloids for fluid resuscitation in critically ill patients.

SEARCH STRATEGY

We searched the Cochrane Injuries Group's specialised register, CENTRAL, MEDLINE, EMBASE, the National Research Register, Web of Science and MetaRegister. Bibliographies of trials and review articles retrieved were searched. The searches were last updated in December 2006.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of colloids compared to crystalloids, in patients requiring volume replacement. Cross-over trials and trials in pregnant women and neonates were excluded.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data and rated quality of allocation concealment. Trials with a 'double-intervention', such as those comparing colloid in hypertonic crystalloid to isotonic crystalloid, were analysed separately. The analysis was stratified according to colloid type and quality of allocation concealment.

MAIN RESULTS

We identified 63 eligible trials, 55 of these presented mortality data. COLLOIDS COMPARED TO CRYSTALLOIDS: Albumin or plasma protein fraction - 23 trials reported data on mortality, including a total of 7,754 patients. The pooled relative risk (RR) from these trials was 1.01 (95% confidence interval [95% CI] 0.92 to 1.10). When the trial with poor quality allocation concealment was excluded, pooled RR was 1.00 (95% CI 0.91 to 1.09). Hydroxyethyl starch - 16 trials compared hydroxyethyl starch with crystalloids, n = 637 patients. The pooled RR was 1.05 (95% CI 0.63 to 1.75). Modified gelatin - 11 trials compared modified gelatin with crystalloid, n = 506 patients. The pooled RR was 0.91 (95% CI 0.49 to 1.72). Dextran - nine trials compared dextran with a crystalloid, n = 834 patients. The pooled RR was 1.24 (95% CI 0.94 to 1.65). COLLOIDS IN HYPERTONIC CRYSTALLOID COMPARED TO ISOTONIC CRYSTALLOID: Eight trials compared dextran in hypertonic crystalloid with isotonic crystalloid, including 1,283 randomised participants. Pooled RR was 0.88 (95% CI 0.74 to 1.05).

AUTHORS' CONCLUSIONS

There is no evidence from RCTs that resuscitation with colloids reduces the risk of death, compared to resuscitation with crystalloids, in patients with trauma, burns or following surgery. As colloids are not associated with an improvement in survival, and as they are more expensive than crystalloids, it is hard to see how their continued use in these patients can be justified outside the context of RCTs.