Are renal adverse effects of hydroxyethyl starches merely a consequence of their incorrect use?

Association of intra-operative hypotension with acute kidney injury, myocardial injury and mortality in non-cardiac surgery: A meta-analysis

BACKGROUND

Intra-operative hypotension might induce poor postoperative outcomes in non-cardiac surgery, and the relationship between the level or duration of Intra-operative hypotension (IOH) and postoperative adverse events is still unclear. In this study, we performed a meta-analysis to determine how IOH could affect acute kidney injury (AKI), myocardial injury and mortality in non-cardiac surgery.

METHODS

We searched PubMed (Medline), Embase, Springer, The Cochrane Library, Ovid and Google Scholar, and retrieved the related clinical trials on intra-operative hypotension and prognosis in non-cardiac surgery.

RESULTS

Fifteen observational studies were included. The meta-analysis showed that in non-cardiac surgery, intra-operative hypotension (mean arterial pressure [MAP]) <60 mm Hg for more than 1 minute was associated with an increased risk of postoperative acute kidney injury(AKI) [1-5 minutes: odds ratio (OR) = 1.13, 95% CI (1.04, 1.23), I²  = 0, P = .003; 5-10 minutes: OR = 1.18, 95% CI (1.07, 1.31), I²  = 0, P = .001; >10 minutes: OR = 1.35, 95% CI (1.1, 1.67), I²  = 52.6%, P = .004] and myocardial injury [1-5 minutes: OR = 1.16, 95% CI (1.01, 1.33), I²  = 30.6%, P = .04; 5-10 minutes: OR = 1.34, 95% CI (1.01, 1.77), I²  = 70.4%, P = .046; >10 minutes: OR = 1.43, 95% CI (1.18, 1.72), I²  = 39.4%, P < .0001]. Intra-operative hypotension (MAP < 60 mm Hg) for 1-5 minutes was not associated with postoperative 30-day mortality [OR = 1.15, 95% CI (0.95, 1.4), I²  = 0, P = .154], but intra-operative hypotension (MAP < 60 mm Hg) for more than 5 min was associated with an increased risk of postoperative 30-day mortality [OR = 1.11, 95% CI (1.06, 1.17), I²  = 51.9%, P < .0001].

CONCLUSION

Intra-operative hypotension was associated with an increased risk of postoperative AKI, myocardial injury and 30-day mortality in non-cardiac surgery. Intra-operative MAP < 60 mm Hg more than 1 minute should be avoided.

Association of intraoperative hypotension with acute kidney injury after elective noncardiac surgery

BACKGROUND

Intraoperative hypotension (IOH) may be associated with postoperative acute kidney injury (AKI), but the duration of hypotension for triggering harm is unclear. The authors investigated the association between varying periods of IOH with mean arterial pressure (MAP) less than 55, less than 60, and less than 65 mmHg with AKI.

METHODS

The authors conducted a retrospective cohort study of 5,127 patients undergoing noncardiac surgery (2009 to 2012) with invasive MAP monitoring and length of stay of 1 or more days. Exclusion criteria were preoperative MAP less than 65 mmHg, dialysis dependence, urologic surgery, and surgical duration less than 30 min. The primary exposure was IOH. The primary outcome was AKI (50% or 0.3 mg/dl increase in creatinine) during the first 2 postoperative days. Multivariable logistic regression was used to model the exposure-outcome relationship.

RESULTS

AKI occurred in 324 (6.3%) patients and was associated with MAP less than 60 mmHg for 11 to 20 min and MAP less than 55 mmHg for more than 10 min in a graded fashion. The adjusted odds ratio of AKI for MAP less than 55 mmHg was 2.34 (1.35 to 4.05) for 11- to 20-min exposure and 3.53 (1.51 to 8.25) for more than 20 min. For MAP less than 60 mmHg, the adjusted odds ratio for AKI was 1.84 (1.11 to 3.06) for 11- to 20-min exposure.

CONCLUSIONS

In this analysis, postoperative AKI is associated with sustained intraoperative periods of MAP less than 55 and less than 60 mmHg. This study provides an impetus for clinical trials to determine whether interventions that promptly treat IOH and are tailored to individual patient physiology could help reduce the risk of AKI.

Hydroxyeyhyl starch: Controversies revisited

Hydroxyethyl starch (HES) family has been one of the cornerstones in fluid management for over four decades. Recent evidence from clinical studies and meta-analyses has raised few concerns about the safety of these fluids, especially in certain subpopulations of patients. High-quality clinical trials and meta-analyses have emphasized nephrotoxic effects, increased risk of bleeding, and a trend toward higher mortality in these patients after the use of HES solutions. Scientific evidence was derived from international guidelines, aggregated research literature, and opinion-based evidence was obtained from surveys and other activities (e.g., internet postings). On critical analysis of the current data available, it can be summarized that further large scale trials are still indicated before HES can be discarded.

[Limited applications for hydroxyethyl starch : background and alternative concepts]

BACKGROUND

Within the framework of a risk assessment procedure the Committee for Risk Assessment of Pharmacovigilance (PRAC) of the European Medicines Agency (EMA) came to the conclusion that the benefits of hydroxylethyl starch infusion solutions (HES) no longer outweighed the risks and on 14 June 2013 recommended that approval should be suspended. Until the procedure has finally been concluded, which could last several months, the Federal Institute for Drugs and Medical Products (BfArM) has recommended that HES should not be used.

AIM

The aim of this article is to present the data situation in the most objective and compact way and to ultimately give the reader the foundations in order to be able to form a personal opinion. In addition an attempt will be made to describe a concept how infusion therapy can be carried out without using hydroxyethyl starch (HES).

MATERIAL AND METHODS

The background to this decision is given based on a review of the literature and the relevance for intensive care, emergency and perioperative medicine is assessed. Furthermore, a concept of infusion therapy without hydroxyethyl starch is formulated also based on the results of current studies.

RESULTS

For infusion regimens without HES it should be noted that gelatin represents a considerable risk for anaphylactic reactions, that transfer of the new variants of Creutzfeldt-Jacob disease (bovine spongiform encephalopathy BSE) cannot fundamentally be excluded and that some evidence has been found that gelatin can cause kidney injury, probably in a similar way to HES. With respect to the cost-benefit analysis of infusion solutions, blood loss in adults of approximately 1-1.5 l can be substituted by balanced crystalloids (basic therapy 4-5 times compared to the amount of blood lost). For larger blood losses small amounts of hyperoncotic albumin solution (20 %) or alternatively 5 % albumin solution can be used. The 20 % albumin solution seems to have some advantages because it has a higher volume effect (approximately 200 %) and can be more favourable for the fluid balance than 5 % albumin solution. Blood losses greater than 2-3 l normally also require administration of blood products (e.g. fresh frozen plasma FFP and erythrocyte concentrates EC).

CONCLUSIONS

The third generation HES solutions cannot be completely replaced by other colloids and in future crystalloids will more strongly again broadly form the basis for infusion therapy. In this aspect balanced crystalloids have priority with respect to the acid-base equilibrium. The history of HES has impressively shown that infusion therapy must be adjusted on a scientifically founded basis, whether in intensive care medicine, perioperative or emergency medicine. Large prospective studies with clinically relevant endpoints are urgently needed.

Reporting bias in trials of volume resuscitation with hydroxyethyl starch

The possibility of renal damage by hydroxyethyl starch has become the focus of intensive dispute based on the findings of published large trials. The aim of this narrative review is to analyze outcome reporting bias in the literature on volume resuscitation, focusing on selective outcome reporting in published randomized and observational trials with “modern” hydroxyethyl starch as therapeutic intervention. Three recent publications claimed to confirm renal safety of hydroxyethyl starch 130/0.4 for indications in severe sepsis, trauma, and critical illness, respectively. Selective outcome reporting was identified in these studies including underreporting of side effects and change of primary study outcomes. In conclusion, selective outcome reporting bias is identified in recent publications of clinical trials on volume resuscitation with HES.

Perioperative intravascular volume replacement and kidney insufficiency

Perioperative acute kidney injury (AKI) occurrence is probably increased in recent years due to the increased level of complexity of surgical procedures and severity of illness of surgical patients. Perioperative AKI has a multifactorial aetiology (preoperative co-morbidities such as diabetes, heart failure and chronic kidney disease, emergent surgery, exposure to nephrotoxic drugs, haemodynamic instability, hypothermia, inflammatory response to surgery, hospital-acquired infections and abdominal compartment syndrome). However, fluid choice for perioperative volume replacement might have a major role in perioperative AKI, as administration of crystalloid solutions, colloids or haemoderivates has the potential for kidney injury. This review focusses on the issue of fluid replacement quality and quantity and their association with renal dysfunction.

Randomised trials of 6% tetrastarch (hydroxyethyl starch 130/0.4 or 0.42) for severe sepsis reporting mortality: systematic review and meta-analysis

PURPOSE

To assess the impact of 6% tetrastarch [hydroxyethyl starch (HES) 130/0.4 and 130/0.42] in severe sepsis patients. The primary outcome measure was 90-day mortality.

METHODS

A structured literature search was undertaken to identify prospective randomised controlled trials (RCTs) in adult patients with severe sepsis receiving 6% tetrastarch (of potato or waxy maize origin) as part of fluid resuscitation in comparison with other non-HES fluids after randomisation in the critical care setting. A systematic review and meta-analysis were performed.

RESULTS

Six RCTs were included (n = 3,033): three from 2012 (n = 2,913) had low risk of bias. Median tetrastarch exposure was 37.4 ml/kg (range 30-43 ml/kg). Ninety-day mortality was associated with tetrastarch exposure [relative risk (RR) 1.13; 95% confidence interval (CI) 1.02-1.25; p = 0.02] compared with crystalloid. The number needed to harm (NNH) was 28.8 (95 % CI 14.6-942.5). Publication bias and statistical heterogeneity (I(2) = 0%) were not present. Tetrastarch exposure was also associated with renal replacement therapy (p = 0.01; NNH 15.7) and allogeneic transfusion support (p = 0.001; NNH 9.9). No difference between groups was observed for 28-day mortality, for comparison with colloid as control, or for waxy maize-derived tetrastarch, but power was lacking. Overall mortality was associated with tetrastarch exposure (RR 1.13; 95% CI 1.02-1.25; p = 0.02).

CONCLUSIONS

In our analysis, 6% tetrastarch as part of initial fluid resuscitation for severe sepsis was associated with harm and, as alternatives exist, in our view should be avoided.