Incidence of acute oligoanuric renal failure in dextran 40 treated patients with acute ischemic stroke stage III or IV

Association Between Aortic Wall Parameters on Multidetector Computed Tomography and Ruptured Plaques By Nonobstructive General Angioscopy

BACKGROUND

Nonobstructive general angioscopy (NOGA) can identify vulnerable plaques in the aortic lumen that serve as potential risk factors for cardiovascular events such as embolism. However, the association between computed tomography (CT) images and vulnerable plaques detected on NOGA remains unknown.

METHODS AND RESULTS

We investigated 101 patients (67±11 years; women, 13.8%) who underwent NOGA and contrast-enhanced CT before or after 90 days in our hospital. On CT images, the aortic wall thickness, aortic wall area (AWA), and AWA in the vascular area were measured at the thickest point from the 6th to the 12th thoracic vertebral levels. Furthermore, the association between these measurements and the presence or absence of NOGA-derived aortic plaque ruptures (PRs) at the same vertebral level was assessed. NOGA detected aortic PRs in the aortic lumens at 145 (22.1%) of the 656 vertebral levels. The presence of PRs was significantly associated with greater aortic wall thickness (3.3±1.7 mm versus 2.1±1.2 mm), AWA (1.33±0.68 cm2 versus 0.89±0.49 cm2), and AWA in the vascular area (23.2%±9.3% versus 17.2%±7.6%) (P<0.001 for all) on the CT scans compared with the absence of PRs. The frequency of PRs significantly increased as the aortic wall thickness increased. Notably, a few NOGA-derived PRs were detected on CT in near-normal intima.

CONCLUSIONS

The presence of NOGA-derived PRs was strongly associated with increased aortic wall thickness, AWA, and AWA in the vascular area, measured using CT. NOGA can detect PRs in the intima that appear almost normal on CT scans.

Routine iso-osmolar contrast media use and acute kidney injury following percutaneous coronary intervention for ST elevation myocardial infarction

BACKGROUND

Temporal changes in contrast-induced acute kidney injury (CI-AKI) incidence following primary percutaneous coronary intervention (PPCI) are poorly defined. Additionally, the benefits of iso-osmolar contrast media (IOCM) compared to low osmolar CM (LOCM) are uncertain.

METHODS

Using data from a regional PPCI service, temporal changes in baseline risk and annual incidence of CI-AKI were studied. A CM protocol change occurred in 2013 allowing a comparison of the incidence of CI-AKI between LOCM (2012-13) and IOCM (2013-15).

RESULTS

Between 2012 and 2015, 208 of 1310 patients experienced CI-AKI (15.9%). The Mehran AKI risk score did not change during the study period although there was an increase in the incidence of CI-AKI in later study years (P<0.001 for trend) when IOCM was used. Factors independently associated with CI-AKI were IOCM use (OR=1.96, [95% CI: 1.39-2.75]), age per year (OR=1.02, 95% CI: 1.01-1.04), baseline creatinine per µmol/L (OR=1.006, 95% CI: 1.003-1.01) and contrast volume per milliliter (OR=1.002, 95% CI: 1.001-1.004). The baseline characteristics of patients treated using IOCM (N.=783) vs. LOCM (N.=527) were similar (Mehran Score 6.6 vs. 6.9, P=0.173) but CI-AKI occurred more frequently with IOCM compared to LOCM (19.2% vs. 11.2%, P<0.001). Use of IOCM was independently associated with CI-AKI (OR=1.98, 95% CI: 1.339-2.774, P<0.001) with consistency across all sub-groups of age, gender, baseline creatinine, contrast volume, shock and diabetes. The adjusted in-hospital mortality was increased with IOCM compared to LOCM (OR=3.03, 95% CI: 1.313-6.994, P=0.009).

CONCLUSIONS

IOCM use was observed to be associated with an increased occurrence of CI-AKI, and an increase in in-hospital mortality after primary PCI.

Efficacy of Dextran Solutions in Vascular Surgery

The purpose of this paper is to discuss the role and efficacy of dextran in vascular procedures using evidence-based data from the review of surgical literature. A MEDLINE search using “dextran,” “vascular surgery,” and “antiplatelet therapy” as keywords was performed for English-language articles. Further references were obtained through cross-referencing the bibliography cited in each work. Dextran is commonly used in carotid endarterectomy (CEA) patients where the embolic rate is reduced by 46%, resulting in fewer procedure-related strokes. As a prophylactic agent against thrombosis, multiple randomized studies have reported its benefit over other antithrombotic medications. Dextran is also particularly useful in “difficult” infragenicular lower extremity bypasses where artificial grafts (such as polytetrafluoroethylene [PTFE] or umbilical vein) are used in the setting of poor outflow vessels, or those with composite grafts and small-caliber venous conduits. Distal bypasses with adjunctive procedures (eg, arteriovenous fistula or anastomotic cuffs) also have a better outcome with the addition of dextran. Dextran has numerous important implications in vascular surgery, in particular with CEA patients or “difficult” infragenicular bypasses. Its effectiveness with endovascular stents remains unknown.

Clinical applications of iron oxide nanoparticles for magnetic resonance imaging of brain tumors

Current neuroimaging provides detailed anatomic and functional evaluation of brain tumors, allowing for improved diagnostic and prognostic capabilities. Some challenges persist even with today's advanced imaging techniques, including accurate delineation of tumor margins and distinguishing treatment effects from residual or recurrent tumor. Ultrasmall superparamagnetic iron oxide nanoparticles are an emerging tool that can add clinically useful information due to their distinct physiochemical features and biodistribution, while having a good safety profile. Nanoparticles can be used as a platform for theranostic drugs, which have shown great promise for the treatment of CNS malignancies. This review will provide an overview of clinical ultrasmall superparamagnetic iron oxides and how they can be applied to the diagnostic and therapeutic neuro-oncologic setting.

Basics of fluid and blood transfusion therapy in paediatric surgical patients

Perioperative fluid, electrolyte and blood transfusion therapy for infants and children can be confusing due the numerous opinions, formulas and clinical applications, which can result in a picture that is not practical and is often misleading. Perioperatively, crystalloids, colloids and blood components are required to meet the ongoing losses and for maintaining cardiovascular stability to sustain adequate tissue perfusion. Recently controversies have been raised regarding historically used formulas and practices of glucose containing hypotonic maintenance crystalloid solutions for perioperative fluid therapy in children. Paediatric intraoperative transfusion therapy, particularly the approach to massive blood transfusion (blood loss ≥ one blood volume) can be quite complex because of the unique relationship between the patient's blood volume and the volume of the individual blood product transfused. A meticulous fluid, electrolyte and blood transfusion management is required in paediatric patients perioperatively because of an extremely limited margin for error. This article reviews the basic concepts in perioperative fluid and blood transfusion therapy for paediatric patients, along with recent recommendations. For this review, Pubmed, Ovid MEDLINE, HINARI and Google scholar were searched without date restrictions. Search terms included the following in various combinations: Perioperative, fluid therapy, paediatrics, blood transfusion, electrolyte disturbances and guidelines. Only articles with English translation were used.

Treatment Outcome of Additional Dextran to Corticosteroid Therapy on Sudden Deafness

Objective

This study aimed to investigate whether adding low-molecular-weight dextran to oral steroids in patients with idiopathic sudden sensorineural hearing loss resulted in better hearing outcomes than those in patients receiving oral corticosteroids alone.

Study Design

Historical cohort study.

Setting

Tertiary teaching hospital.

Subjects and Methods

The authors reviewed the clinical records of 166 patients with idiopathic sudden sensorineural hearing loss. Therapeutic effectiveness was measured by the gain of pure-tone averages and 4 categories of hearing outcome (complete recovery, marked recovery, mild improvement, or no improvement). To manage potential confounding factors associated with treatment allocation, the authors matched the subjects from each group according to the propensity score (ie, the predicted probability that they would receive a specific treatment).

Results

The authors identified 50 pairs of propensity score–matched subjects (n = 100) without significant difference of all clinical factors ( P > .05). Subsequent analyses demonstrated that the average hearing gain in subjects receiving additional dextran to oral steroid was 31.7 ± 21.5 dB, which did not differ from 33.0 ± 21.8 dB in subjects receiving steroids alone ( P = .76). Difference of hearing outcomes between the 2 groups was also nonsignificant ( P = .92).

Conclusion

Matching propensity scores successfully balanced the heterogeneity between the dextran and steroid groups. Analytical results demonstrated that adding low-molecular-weight dextran to oral corticosteroids was not associated with greater hearing gain or better hearing outcome in idiopathic sudden sensorineural hearing loss.

Hydroxyethylstarch 200/0.5--the horse has bolted

Hydroxyethylstarch (HES) 200/0.5 is associated with renal failure. Several studies have suggested that renal function is affected but the subsequent arguments leave the clinician in no man's land. A recent study in Critical Care by Simon and colleagues using a two hit animal model of shock demonstrates that the use of a higher molecular weight starch, HES 200/0.5, is associated with impaired renal function when compared with ringers acetate, gelatin or a lower molecular weight starch, HES 130/0.42. The authors conclude that both the lower molecular weight starch and the ringers acetate 'preserve renal function and attenuate tubular damage better than 10% hydroxyethylstarch 200/0.5 in saline'. Added to the previous evidence, the renal effects of HES200/0.5 are probably real. Many clinicians have already moved to the lower molecular weight starches on the basis of doubt rather than certainty, but this study tips the balance. The cause remains elusive and the lack of a mechanism should be seen as a problem.

Colloids and crystalloids: does it matter to the kidney?

PURPOSE OF REVIEW

To highlight some of the recent key issues surrounding crystalloid and colloid fluid management of critically ill patients.

RECENT FINDINGS

Significant developments have been made in the understanding of ionic balance of fluids and their effects on acid-base, the role of hydration and overhydration, alkalinization of fluids in patients at high risk for contrast induced nephropathy, and finally the role of colloids in acute kidney injury.

SUMMARY

Despite hydration remaining a key principle in fluid management in many patients, volume overload is of considerable concern. Recent evidence also suggests that balanced electrolyte formulations are preferable to saline-based formulations in a variety of clinical settings. Furthermore, alkalinization of fluids is protective in the setting of contrast-induced nephropathy. Oncotic load appears to be the most important factor in acute kidney injury associated with colloid fluid therapy.

The ratio of the blood urea nitrogen/creatinine index in patients with acute renal failure is decreased due to dextran or mannitol

Acute renal failure (ARF) induced by dextran or mannitol is a lethal adverse effect, and hemodialysis or plasma exchange is recommended to avoid fatal ARF. This report describes 2 cases of ARF; one caused by dextran and the other by mannitol. Both showed decreases in the blood urea nitrogen (BUN)/creatinine ratios after the administration of these reagents. They immediately recovered to the level of creatinine on admission after the administration of these reagents was stopped, without hemodialysis or plasma exchange. Decreases in the BUN/creatinine ratio might be a useful index for the diagnosis of ARF is caused by these reagents.

Perioperative crystalloid and colloid fluid management in children: where are we and how did we get here?

It has been more than 50 yr since the landmark article in which Holliday and Segar (Pediatrics 1957;19:823-32) proposed the rate and composition of parenteral maintenance fluids for hospitalized children. Much of our practice of fluid administration in the perioperative period is based on this article. The glucose, electrolyte, and intravascular volume requirements of the pediatric surgical patient may be quite different than the original population described, and consequently, use of traditional hypotonic fluids proposed by Holliday and Segar may cause complications, such as hyperglycemia and hyponatremia, in the postoperative surgical patient. There is significant controversy regarding the choice of isotonic versus hypotonic fluids in the postoperative period. We discuss the origins of perioperative fluid management in children, review the current options for crystalloid fluid management, and present information on colloid use in pediatric patients.

Osmotic nephrosis: acute kidney injury with accumulation of proximal tubular lysosomes due to administration of exogenous solutes

Osmotic nephrosis describes a morphological pattern with vacuolization and swelling of the renal proximal tubular cells. The term refers to a nonspecific histopathologic finding rather than defining a specific entity. Osmotic nephrosis can be induced by many different compounds, such as sucrose, hydroxyethyl starch, dextrans, and contrast media. It has a broad clinical spectrum that includes acute kidney injury and chronic kidney failure in rare cases. This article discusses the pathological characteristics, pathogenesis, and various clinical entities of osmotic nephrosis.

The influence of volume management on outcome

PURPOSE OF REVIEW

Fluid (volume) therapy is an integral component in the management of critically ill patients and fluid management may influence outcome. There is much controversy, however, about the type, timing and amount of fluid therapy. Here, we discuss the evidence available to guide such choices.

RECENT FINDINGS

Fluid therapy is widely endorsed for resuscitation of critically ill patients across a range of conditions. Yet, the approach to fluid therapy is subject to substantial variation in clinical practice. Emerging data show that the choice, timing and amount of fluid therapy may affect clinical outcomes. Synthetic colloids may increase the risk of acute kidney injury. Albumin may benefit hypoalbuminemic patients with sepsis and acute lung injury but may worsen outcome in traumatic brain injury. Early administration of fluid therapy in sepsis may improve survival but may be unnecessary in patients with penetrating trauma. Later fluid therapy in acute lung injury patients will increase the duration of ventilator dependence without achieving better survival. A positive cumulative balance likely contributes to increased morbidity and mortality after major surgery.

SUMMARY

Emerging evidence shows that choice, timing and amount of fluid therapy affect outcome. Future studies need to focus on these aspects of fluid therapy by means of larger, more rigorous and blinded controlled trials.

Blood volume expansion with hyperoncotic colloids deteriorates allograft function in a canine model of renal transplantation

PURPOSE

We investigated the effects of acute maximal hydratation with hemoce (H) and dextran-40 (D40) on the postoperative graft function, following renal transplantation (RT) in a canine model.

METHODS

After induction of anesthesia with pentobarbital (5 mg/kg), 18 beagle dogs were randomized to receive either saline solution to increase the central venous pressure (CVP) to 5 mm Hg (GI); H solution to increase the CVP to 10 mm Hg (GII); or D40 to achieve 15 mm Hg (GIII), before reperfusion. A pulmonary artery catheter was used to measure CVP, mean pulmonary artery pressure, and cardiac output (CO). The surgical procedure consisted of autotransplantation of the dog's left kidney an hour prior to cold ischemia with University of Wisconsin solution, followed by contralateral nephrectomy. Diuresis, creatinine (Cr), and BUN levels were measure at 24 hours before RT, as well as 24, 48, and 72 hours after the procedure.

RESULTS

Only in the treated groups did cardiac filling pressures and CO increase as a result of hydration. Only in the GI group did serum Cr and blood urea nitrogen significantly peak at the second postoperative day while it continued to increase at two (GII) and three (GIII) times greater than GI on the third day. Histological examination showed osmotic nephrosis like-lesions only among treated grafts.

CONCLUSION

We concluded that maximal hydration with H and D40 colloid deteriorated postoperative graft function after RT. We believe that in the future the effects of any colloid solution should be tested in an animal model in the fashion as we have described, in order to know which one, and at what dose, is the safest to improve kidney allograft outcome.

Perioperative fluid management in renal transplantation: a narrative review of the literature

Adequate volume maintenance is essential to prevent acute renal failure during major surgery or to ensure graft function after renal transplantation. The various recommendations on the optimum fluid therapy are based, at best, on sparse evidence only from observational studies. This article reviews the literature on perioperative fluid management in renal transplantation. Crystalloid solutions not exerting any specific side-effects are the first choice for volume replacement in kidney transplantation. The use of colloids should be restricted to patients with severe intravascular volume deficits necessitating high volume restoration. The routine application of albumin, dopamine, and high dose diuretics is no longer warranted. Mannitol given immediately before removal of the vessel clamps reduces the requirement of post-transplant dialysis, but has no effects on graft function in the long term. There is insufficient evidence on the best use of dialysis, but it seems peritoneal dialysis pretransplant is associated with less delayed graft function, whereas the preference of dialysis post-transplant is not yet well-founded. This review article should provide better guidance for fluid management in kidney transplantation until best-evidence guidelines can be established based upon more research.

Renal failure in 57925 patients undergoing coronary procedures using iso-osmolar or low-osmolar contrast media

We compared the Swedish Coronary Angiography and Angioplasty Registry with the Swedish 'Hospital Discharge Register' to assess contrast media (CM)-induced renal failure. Hospitals used only one type CM. From 2000 to 2003, iodixanol (iso-osmolar) was used in 45 485 patients, ioxaglate (low osmolar) in 12 440 subjects. To include the earlier used CM iohexol (low osmolar), analysis extended back to 1990 (86 334 patients). Incidence of clinically significant renal failure was greatest for patients receiving the iso-osmolar CM iodixanol (1.7%). Ioxaglate-treated patients had a significantly lower renal failure incidence (0.8%, P<0.001). The odds ratio for iodixanol-treated patients was significantly higher than for ioxaglate (1 vs 0.48, P<0.001). In subsets of either diabetic patients or patients with previous renal failure, odds ratios for renal failure remained greater in the iodixanol groups (P<0.01). Hospitals switching CM to iodixanol experienced a doubling in clinically significant renal failure after cardiac procedures. Dialysis was required in 0.2% of patients receiving iodixanol, which was significantly higher (P<0.01) than for ioxaglate-treated patients (0.1%). Iohexol-treated patients had a similar low risk for developing clinically significant renal failure (0.9%) as ioxaglate. In conclusion, risk of developing renal failure and required dialysis after coronary procedures is higher when patients received iodixanol than ioxaglate or iohexol.

Renal impact of fluid management with colloids: a comparative review

BACKGROUND AND OBJECTIVES

Colloids such as hydroxyethyl starch (HES), gelatin, dextran and albumin are useful for maintaining renal perfusion and function. The comparative renal effects of colloids have not been previously reviewed.

METHODS

Computer searches of the MEDLINE and EMBASE bibliographic databases and the Cochrane Library were conducted using the search terms: colloids; hetastarch; gelatin; dextrans; serum albumin; kidney failure; cardiac surgical procedures; and kidney transplantation. Relevant studies were also sought through hand searching and examination of reference lists. Results of identified studies were qualitatively summarized with account taken for potential confounding factors.

RESULTS

The three artificial colloids HES, gelatin and dextran all exhibited troublesome renal side-effects. Randomized trials have demonstrated adverse renal effects of HES in sepsis and surgery. Undesirable renal effects are common to all available HES solutions regardless of molecular weight, substitution or C2/C6 ratio. While some of its effects may be less severe than those of HES, gelatin also can adversely affect the kidney. A negative renal impact of dextran is well-established, although this colloid is now less extensively used than formerly. As the normal endogenous colloid, albumin exhibits a wide margin of renal safety, although albumin overdose needs to be avoided. Albumin also appears to exert protective effects on the kidney such as inhibition of apoptosis and scavenging of reactive oxygen species.

CONCLUSIONS

Colloids display important differences in their actions on the kidney. These contrasting renal effects should be considered in making fluid management decisions.

New Light on Intravascular Volume Replacement Regimens: What Did We Learn from the Past Three Years?

Definition of the "ideal" intravascular fluid volume replacement strategy still remains a critical problem. This article analyzes studies on volume replacement by using a MEDLINE search of the past 3 years (from January 1, 2000, to December 12, 2002). Forty original studies in humans with a total of 2454 subjects were identified. Five studies were performed in volunteers (n = 113); the other 35 studies (n = 2341) were performed in a variety of patients (e.g., cardiac surgery, trauma patients, children, and intensive care unit patients). The influence of different volume replacement regimens on coagulation was one of the major topics of interest (16 studies with 1183 subjects), and other studies focused on metabolic state, alterations in macro- and microcirculation, volume distribution, and organ function (e.g., kidney function and splanchnic perfusion). Among all synthetic colloids, hydroxyethyl starch (HES) was the solution most often studied. Two new HES preparations have been approved (Hextend), a balanced hetastarch solution, and a new third-generation HES [130/0.4]). Only two studies used albumin, and no superiority of albumin was found over less expensive synthetic colloids. In almost all studies, the outcome either was no end-point or was not reported. Volume replacement has often been hitherto based on dogma and personal beliefs. Future well performed studies in this area will hopefully help to shed new light on the ideal volume replacement strategy.

IMPLICATIONS

By using a MEDLINE search covering the last 3 yr, the present knowledge on volume replacement regimens was analyzed. Forty studies in humans were identified. New hydroxyethyl starch preparations have shed light on this topic, whereas no additional data supporting the use of albumin have been presented.

Dextran-induced pulmonary edema in patients with sudden deafness

OBJECTIVE

Pulmonary complication in cases of sudden deafness after dextran treatment is rarely reported. This study discusses the management of two cases and reviews the current literature.

PATIENTS

Two (1%) of 204 patients with sudden deafness patients had fever, cough, and dyspnea after intravenous dextran infusion. Pulmonary edema was diagnosed after chest radiographic examination.

RESULTS

After interruption of dextran, subsequent supportive treatment relieved chest discomfort and fever without any sequelae. The results of chest radiograph and laboratory studies, including hemogram, renal function, and arterial blood oxygen saturation, were normal.

CONCLUSIONS

Patients receiving dextran treatment should have their clinical symptoms, renal function, chest radiographs, hemogram, and coagulation profiles monitored. If fever, bleeding, cough, or dyspnea occurs during treatment, dextran must be immediately stopped. Subsequent treatment should focus on dextran clearance to prevent further cascade complications.

Complication of oliguric acute renal failure in patients treated with low-molecular weight dextran

Acute renal failure (ARF) is a well-documented but infrequent complication in patients treated with low-molecular weight dextran (LMWD). We herein report 3 cases of oliguric ARF following the administration of dextran-40. One case developed ARF totally after 1.200 g of LMWD administration. In contrast, two cases having increased serum creatinine developed oliguria despite the acceptable therapeutic doses (totally 450 and 650 g). Contrast media was also co-administered in these patients. Plasma exchange (PE), double filtration plasmapheresis (DFPP), or continuous hemodiafiltration (CHDF) but not hemodialysis (HD) reduced circulating dextran concentrations by 35-44% during a single session. All patients completely recovered from ARF by 14-32 days after the treatment. Our cases suggested that radiocontrast could predispose to the development of LMWD-induced ARF especially in patients having pre-existing renal dysfunction. In addition, PE, DFPP and CHDF afforded a beneficial effect for removing accumulated LMWD from the circulation.

Volume Replacement in Critically Ill Patients with Acute Renal Failure

Abstract. Maintenance and restoration of intravascular volume are essential tasks of critical care management to achieve sufficient organ function and to avoid multiple organ failure in critically ill patients. Inadequate intravascular volume followed by impaired renal perfusion is the predominate cause of acute renal failure. Crystalloid solutions are the first choice to correct fluid and electrolyte deficits in these patients. However, in case of major hypovolemia, particularly in situations of increased capillary permeability, colloid solutions are indicated to achieve sufficient tissue perfusion. Whereas albumin should be avoided for correction of intravascular hypovolemia, synthetic colloids can restore intravascular volume and stabilize hemodynamic conditions. In addition to a faster, more effective and prolonged restoration of intravascular volume, colloid solutions are able to improve microcirculation. Of the synthetic colloids, hydroxyethyl starch (HES) solutions with a low in vivo molecular weight, such as HES 200/0.5, offer the best risk/benefit ratio. These solutions are safe with respect to effects on coagulation, platelets, reticuloendothelial system, and renal function, if used below their upper dosage limits. For patients with acute renal dysfunction, daily monitoring of renal function is necessary if colloids are required to stabilize hemodynamic conditions. In these patients, measurement of the colloidal osmotic pressure and adequate amounts of crystalloid solutions will reduce the risk of hyperoncotic renal failure. Of all colloids, gelatin and HES solutions with low in vivo molecular weight are preferred in these cases. In the very specific situation of kidney transplantation, colloid solutions should be administered in a restricted manner to organ donors and kidney recipients.