Blood purification for crush syndrome

Kidney replacement and conservative therapies in rhabdomyolysis: a retrospective analysis

BACKGROUND

Toxic renal effects of myoglobin following rhabdomyolysis can cause acute kidney injury (AKI) with the necessity of kidney replacement therapy (KRT). Fast elimination of myoglobin seems notable to save kidney function and intensify kidney repair. Clinical data regarding efficacy of KRT in critical care patients with rhabdomyolysis and AKI are limited. This retrospective analysis aimed to identify differences between conservative therapy and different modalities of KRT regarding myoglobin elimination and clinical outcome.

METHODS

This systematic, retrospective, single-center study analyzed 328 critical care patients with rhabdomyolysis (myoglobin > 1000 µg/l). Median reduction rate of myoglobin after starting KRT was calculated and compared for different modalities. Multivariate logistic regression models were established to identify potential confounder on hospital mortality. Filter lifetime of the various extracorporeal circuits was analyzed by Kaplan-Meier curves.

RESULTS

From 328 included patients 171 required KRT. Health condition at admission of this group was more critical compared to patient with conservative therapy. Myoglobin reduction rate did not differ between the groups (KRT 49% [30.8%; 72.2%] vs. conservative treatment (CT) 61% [38.5%; 73.5%]; p = 0.082). Comparison between various extracorporeal procedures concerning mortality showed no significant differences. Hospital mortality was 55.6% among patients with KRT and 18.5% with CT (p < 0.001). Multivariate logistic regression model identified requirement for KRT (OR: 2.163; CI: 1.061-4.407); p = 0.034) and the SOFA Score (OR: 1.111; CI: 1.004-1.228; p = 0.041) as independent predictive factors for hospital mortality. When comparing specific KRT using multivariate regression, no benefit was demonstrated for any treatment modality. Life span of the extracorporeal circuit was shorter with CVVH compared to that of others (log-Rank p = 0.017).

CONCLUSIONS

This study emphasizes that AKI requiring KRT following rhabdomyolysis is accompanied by high mortality rate. Differences in myoglobin reduction rate between various KRTs could not be confirmed, but CVVH was associated with reduced filter lifetime compared to other KRTs, which enable myoglobin elimination, too.

The Role of Alpha-1-Acid Glycoprotein in the Diagnosis and Treatment of Crush Syndrome-Induced Acute Kidney Injury

BACKGROUND

Crush syndrome (CS) is the most common cause of deaths following earthquakes and other disasters. The pathogenesis of CS has yet to be fully elucidated. Thus, clinical choice of ideal drug treatments for CS remains deficient.

METHODS AND RESULTS

In this study, we first evaluated the relation between extrusion force and the severities of CS. Rats were exposed to different extrusion forces: 1 kg, 3 kg, 5 kg, and 8 kg, respectively. Survival rates, crushed muscle tissue edema, serum biochemical parameters, and histopathological staining were used to assess severity. Our results showed that there were no statistical differences in survival rate or changes in thigh circumference among the different extrusion forces groups. However, serum levels of potassium, creatine kinase, blood urea nitrogen, creatinine, and myoglobin were elevated at 12- and 24-h post-decompression in 5 kg and 8 kg groups, compared with 1 kg and 3 kg groups. Histopathological staining demonstrated that the degree of organ damage to kidney, muscle, and lung tissues correlated with increasing extrusion force. We next analyzed changes in serum protein profiles in 3 kg or 5 kg extrusion pressure groups. A total of 76 proteins (20 upregulated, 56 downregulated) were found to be altered at all three time points (0, 12, and 72 h) post-decompression, compared with the control group. Three common upregulated proteins alpha-1-acid glycoprotein (α1-AGP), neutrophil gelatinase-associated lipocalin (NGAL), and Haptoglobin were selected for validation of increased expression. α1-AGP was explored as a treatment for CS-induced acute kidney injury (AKI). Intraperitoneal injection of α1-AGP protected kidneys from CS-induced AKI by regulating TNF-α and IL-6 production, attenuating neutrophil recruitment, and reducing renal cell apoptosis.

CONCLUSION

Our findings demonstrated that the severity of crush injury is causally related to extrusion pressure and increase in blood serum markers. Our identification of the biomarker and treatment candidate, α1-AGP, suggests its implication in predicting the severity of CS and its use as a mediator of CS-induced AKI, respectively.

Myoglobin clearance with continuous veno-venous hemodialysis using high cutoff dialyzer versus continuous veno-venous hemodiafiltration using high-flux dialyzer: a prospective randomized controlled trial

Background

Myoglobin clearance in acute kidney injury requiring renal replacement therapy is important because myoglobin has direct renal toxic effects. Clinical data comparing different modalities of renal replacement therapy addressing myoglobin clearance are limited. This study aimed to compare two renal replacement modalities regarding myoglobin clearance.

Methods

In this prospective, randomized, single-blinded, single-center trial, 70 critically ill patients requiring renal replacement therapy were randomized 1:1 into an intervention arm using continuous veno-venous hemodialysis with high cutoff dialyzer and a control arm using continuous veno-venous hemodiafiltration postdilution with high-flux dialyzer. Regional citrate anticoagulation was used in both groups to maintain the extracorporeal circuit. The concentrations of myoglobin, urea, creatinine, β2-microglobulin, interleukin-6 and albumin were measured before and after the dialyzer at 1 h, 6 h, 12 h, 24 h and 48 h after initiating continuous renal replacement therapy.

Results

Thirty-three patients were allocated to the control arm (CVVHDF with high-flux dialyzer) and 35 patients to the intervention arm (CVVHD with high cutoff dialyzer). Myoglobin clearance, as a primary endpoint, was significantly better in the intervention arm than in the control arm throughout the whole study period. The clearance values for urea and creatinine were higher in the control arm. There was no measurable albumin clearance in both arms. The clearance data for β₂-microglobulin and interleukin-6 were non-inferior in the intervention arm compared to those for the control arm. Dialyzer lifespan was 57.0 [38.0, 72.0] hours in the control arm and 70.0 [56.75, 72.0] hours in the intervention arm (p = 0.029).

Conclusions

Myoglobin clearance using continuous veno-venous hemodialysis with high cutoff dialyzer and regional citrate anticoagulation is better than that with continuous veno-venous hemodiafiltration with regional citrate anticoagulation.

Trial registration

German Clinical Trials Registry (DRKS00012407); date of registration 23/05/2017. https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00012407.

Amputation in crush syndrome: A case report

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Crush syndrome (CS) produces severe electrolyte disorders, circulatory and multiple organ failure due to severe rhabdomyolysis and reperfusion injuries.

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To date, the main stem of management is aggressive fluid resuscitation.

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Fasciotomy for the treatment of compartment syndromes due to crush injuries is still controversial, and it is still unknown if early amputation has patient-centered benefits.

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This case suggests a potential benefit of amputation in patients with CS and progressive deterioration. It also invites to think if this is a decision to consider early in the course of the disease.

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The presence of risk factors for poor prognosis and the natural course of the disease can favor amputation despite the apparent viability of the limb and the morbidity of losing of an extremity.

Introduction

Crush syndrome (CS) is a condition with a high morbidity and mortality due to severe electrolyte disorders, circulatory dysfunction and multiple organ failure, secondary to severe rhabdomyolysis and reperfusion injuries. There is controversy about the role of fasciotomy in the treatment of compartment syndromes due to crush injuries and it is still unknown if early amputation has patient-centered benefits.

Case presentation

This is a 29-year-old patient whose lower body was trapped for 50 h under a 40-meter landslide. Upon admission the left thigh was edematous and painful. Laboratories revealed a creatinine of 1.58 mg/dL, hyperkalemia, metabolic acidosis, hyperlactatemia and creatinine phosphokinase (CPK) of 88,700 U/L, suggesting CS. Despite fluid and bicarbonate infusion his renal function worsened, CPK rose and left thigh became more tense, so a fasciotomy was performed. He developed a distributive shock refractory to vasopressors, steroids and methylene blue so amputation was proposed. Two hours after amputation the vasopressor support was nearly withdrawn.

Discussion

This case suggests a potential benefit of amputation in patients with CS and progressive deterioration despite aggressive resuscitation. It also invites to think if this is a decision that should be considered before the establishment or in the initial stages of the syndrome, even if the viability of the extremity is still questionable.

Conclusion

The presence of risk factors for poor prognosis can favor amputation despite the apparent viability of the limb and the morbidity of losing an extremity.

Transfusion under triple threat: Lessons from Japan's 2011 earthquake, tsunami, and nuclear crisis

The Great East Japan Earthquake of March 11, 2011 provoked tsunami waves with inland penetration up to 5 km and run-up heights to 40 m. More than 400 km² were flooded, mainly along the northeast coast of Japan's largest island, Honshu. Nearly 20,000 human lives were abruptly taken by this natural disaster. Four coastal nuclear facilities went into automatic shutdown; at one, Fukushima Daiichi, cooling system failures resulted in the meltdown of three reactor cores, accompanied by explosive release of radioisotopes. Essentials of modern blood banking and transfusion medicine were lost: roads, vehicles, blood collection venues, and facilities for blood testing and processing. Normal channels of communication were interrupted, not only by physical damage but also due to circuit overload as mobile phone users sought information and tried to exchange messages about their own and others' health, welfare, and whereabouts. The Japanese Red Cross, as a monopoly supplier of allogeneic blood, responded with a nationally coordinated effort that met the transfusion demands of a disaster characterized by immediate mass fatality rather than mass injury. Japan's routine transfusion demands are also met by hospital-based autologous blood programs, which could be pressed into service for emergency allogeneic collections. Herein we report institutional and personal experience in anticipation of future disasters, in which transfusion needs might differ from routine demand.

Activated carbons and carbon-containing poly(vinyl alcohol) cryogels: characterization, protein adsorption and possibility of myoglobin clearance

Adsorption of myoglobin (Mb), bovine serum albumin (BSA) and γ-globulin (GG) onto activated carbons (ACs) with different pore size distributions, and poly(vinyl alcohol) (PVA) monolithic cryogels containing AC particles was studied. The highest initial rate of Mb adsorption was observed for AC having the largest specific surface area (1939 m(2) g(-1)) and pore volume (1.82 cm(3) g(-1)). The adsorption kinetics of proteins was characterized by a bimodal shape of the distribution f(D) function of an effective diffusion coefficient. Adsorption isotherms of Mb and GG were of Freundlich type within the studied range of equilibrium concentrations (10-150 μg mL(-1)). The distributions of free energy of protein adsorption were bimodal and reflected both interactions with carbon surfaces and self-association of proteins. Adsorbed amounts of Mb were the highest among the proteins studied (up to 700 mg g(-1) carbon), which was attributed to the higher fraction of pores accessible for Mb. Incorporation of carbon particles into PVA-based cryogel resulted in macroporous monolithic composite materials (AC-PVA) exhibiting good flow-through properties. Scanning electron microscopy of the composites showed macroporous aggregates of carbon particles held together by films and bridges of PVA. The rates of adsorption and adsorbed amounts of proteins on AC-PVA were reduced compared to the pristine carbon and depended on the carbon content in the composites. Nevertheless, adsorption of Mb on AC-PVA took place even in the presence of 500-fold higher concentration of BSA. This indicated a possibility of Mb clearance from blood plasma using the PVA-carbon monoliths.

The great East Japan earthquake of March 11, 2011, from the vantage point of blood banking and transfusion medicine

BACKGROUND

The Great East Japan Earthquake of March 11, 2011, and subsequent tsunami took nearly 20 000 lives in Tohoku, the northeastern part of Japan's main island. Most victims were either carried away by the tsunami or drowned. The ability to collect blood was disrupted on the Pacific coast of Tohoku. Inland areas were less affected, but allogeneic blood collected in Tohoku is tested at the Miyagi Red Cross Blood Center (Miyagi Center) in the coastal city of Sendai. Miyagi Center was damaged and could not test for 2 months.

OBJECTIVES

The aims of this study are as follows: (1) to assess transfusion practice at 8 disaster response hospitals in Tohoku's Fukushima Prefecture, for equal intervals before and after March 11, 2011; (2) to report activities related to blood collection and distribution in response to the disaster; and (3) to describe the Great East Japan Earthquake in the context of other disasters.

METHODS

Data were collected through a survey of transfusion services at 8 major disaster response hospitals, communication at transfusion conferences, and literature review.

RESULTS

Transfused patients and units transfused were about 70% and 60% of normal in the surveyed hospitals because this was a disaster of mass casualty rather than mass injury, and patients requiring chronic care were evacuated out. A nationally coordinated effort allowed excess blood collected outside Tohoku to be transported in, despite infrastructure damage.

CONCLUSION

Japan's national system of blood collection and distribution responded effectively to local needs after the Great East Japan Earthquake. Disasters such as Japan's 3.11 should guide discourse about emergency preparedness and centralization of services.

Myoglobin clearance by continuous venous-venous haemofiltration in rhabdomyolysis with acute kidney injury: a case series

BACKGROUND

Clearance of circulating myoglobin is a critical measure to prevent further damage in patients with rhabdomyolysis (RM) and acute kidney injury (AKI). Continuous venous-venous haemofiltration has emerged to be a novel approach for this purpose. The objective of present study is to evaluate the efficacy and safety of CVVH in myoglobin clearance for patients with RM complicated with AKI.

METHOD

We prospectively analysed 15 patients with acute RM and AKI due to crush syndrome (n=7), bee stings (n=5), polymyositis (n=2) and heroin poisoning (n=1). All of them presented oliguria with high serum myoglobin and creatine kinase concentration. They were treated by CVVH for at least 48h until the conditions turned to be stable, then replaced by intermittent renal replacement therapy (intermittent haemofiltration or haemodialysis). Meanwhile intravascular volume expansion, urinary alkalinisation, and forced diuresis were administered. During the procedure, serum and effluent concentrations of myoglobin and creatinine were measured simultaneously at 2, 6, 12 and 24h.

RESULT

The mean sieving coefficients for myoglobin were 0.28±0.06, 0.21±0.06, 0.15±0.02 and 0.11±0.02 during 2, 6, 12 and 24h of CVVH intervention, whilst mean clearance of myoglobin was 14.3±3.1ml/min during 2h and reduced to 11.5±3.2, 7.5±0.9, 5.6±1.0ml/min during 6, 12 and 24h. In contrast to myoglobin, the sieving coefficient for creatinine remained stable at 0.95±0.25, 1.02±0.12, 0.89±0.32, 0.98±0.27 during 24h of CVVH. In all of the 15 patients, serum myoglobin and creatine kinase were dramatically decreased in 24h (-56.2 and -32.1%), 3 days (-72.9 and -50.3%) and in 7 days (-97.6 and -96.7%). Seven patients (46.7%) complicated with hypophosphatemia during CVVH intervention improved in natural course after the cessation of CVVH. After 16±12 days, all of 15 patients came to polyuria stage and finally, discharged with normal renal function after 31±15 days.

CONCLUSION

Our study showed CVVH can be employed to clear myoglobin effectively in patients with RM and AKI and presented oliguria. This indicate that CVVH would be better than other modes of renal replement treatment in acute RM with AKI because of the additional benefit of myoglobin removal, but large sample randomised controlled trials are still required to confirm it.

Crush injuries and crush syndrome — a review. Part 1: the systemic injury

Crush injuries can occur in large numbers following natural disasters or acts of war and terrorism. They can also occur sporadically after industrial accidents or following periods of unconsciousness from drug intoxication, anaesthesia, trauma or cerebral events. A common pathophysiological pathway has been elucidated over the last century describing traumatic rhabdomyolysis leading to myoglobinuric acute renal failure and a systemic ‘crush syndrome’ affecting many organ systems. If left unrecognised or untreated, then mortality rates are high. If treatment is commenced early and the systemic effects are minimised then patients are often faced with significant morbidity from the crushed limbs themselves. We have performed a thorough review of the English language literature from 1940 to 2009 investigating crush injuries and crush syndrome and present a comprehensive, two-part summary. Part 1: The systemic injury: In this part we concentrate on the systemic crush syndrome. We determine the pathophysiology, clinical and prognostic indicators and treatment options such as forced alkaline diuresis, mannitol therapy, dialysis and haemofiltration. We discuss more controversial treatment options such as allopurinol, potassium binders, calcium therapy and other diuretics. We also discuss the specific management issues of the secondary ‘renal disaster’ that can occur following earthquakes and other mass disasters. Part 2: The local injury: Here we look in more detail at the pathophysiology of skeletal muscle damage following crush injuries and discuss how to minimise morbidity by salvaging limb function. In particular we discuss the controversies surrounding fasciotomy of crushed limbs and compare surgical management with conservative techniques such as mannitol therapy, hyperbaric oxygen therapy, topical negative pressure therapy and a novel topical treatment called gastric pentadecapeptide BPC 157.

Prevention of acute kidney injury and protection of renal function in the intensive care unit. Expert opinion of the Working Group for Nephrology, ESICM

BACKGROUND

Acute renal failure on the intensive care unit is associated with significant mortality and morbidity.

OBJECTIVES

To determine recommendations for the prevention of acute kidney injury (AKI), focusing on the role of potential preventative maneuvers including volume expansion, diuretics, use of inotropes, vasopressors/vasodilators, hormonal interventions, nutrition, and extracorporeal techniques.

METHOD

A systematic search of the literature was performed for studies using these potential protective agents in adult patients at risk for acute renal failure/kidney injury between 1966 and 2009. The following clinical conditions were considered: major surgery, critical illness, sepsis, shock, and use of potentially nephrotoxic drugs and radiocontrast media. Where possible the following endpoints were extracted: creatinine clearance, glomerular filtration rate, increase in serum creatinine, urine output, and markers of tubular injury. Clinical endpoints included the need for renal replacement therapy, length of stay, and mortality. Studies are graded according to the international Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) group system.

CONCLUSIONS AND RECOMMENDATIONS

Several measures are recommended, though none carries grade 1A. We recommend prompt resuscitation of the circulation with special attention to providing adequate hydration whilst avoiding high-molecular-weight hydroxy-ethyl starch (HES) preparations, maintaining adequate blood pressure using vasopressors in vasodilatory shock. We suggest specific vasodilators [corrected] under strict hemodynamic control, sodium bicarbonate for emergency procedures administering contrast media, and periprocedural hemofiltration in severe chronic renal insufficiency undergoing coronary intervention.

ELECTRONIC SUPPLEMENTARY MATERIAL

The online version of this article (doi:10.1007/s00134-009-1678-y) contains supplementary material, which is available to authorized users.

The effect of combining intermittent hemodiafiltration with forced alkaline diuresis on plasma myoglobin in rhabdomyolysis

BACKGROUND

Our aim was to examine the effect of combining intermittent hemodiafiltration (HDF) with forced alkaline diuresis on plasma myoglobin in rhabdomyolysis.

METHODS

This was a prospective, randomized, controlled, cross-over study. Sixteen rhabdomyolysis patients with plasma myoglobin concentrations above 10,000 microg/l were randomized. Forced alkaline diuresis was started immediately after allocation and continued throughout the study. HDF, which lasted for 4 h, was started in group A immediately after allocation and in group B 4 h later. The primary analysis was intention-to-treat by repeated measures analysis of variance and Mann-Whitney U-test.

RESULTS

The percentage elimination of myoglobin from the circulation during HDF differed significantly from that during alkaline diuresis (28.1% vs. 14.2%, respectively; P < 0.01). The mean decrease in plasma myoglobin concentration during HDF [9731 microg/l; 95% confidence interval (CI), 3672-5345 microg/l] and forced alkaline diuresis (3646 microg/l; 95% CI, 1260-6032 microg/l) did not show a statistically significant difference (P= NS). The mean total amount of myoglobin found in the ultrafiltrate was 58.4 mg.

CONCLUSION

The percentage myoglobin decrease during combined HDF and forced alkaline diuresis was higher than that during forced alkaline diuresis alone. Renal replacement therapy with filtration techniques may be considered for the clearance of myoglobin from plasma when urine alkalinization is not successful.

Reviews: The Current State of Nonuremic Applications for Extracorporeal Blood Purification

Despite the commonly accepted indications for hemodialysis and extracorporeal depuritive techniques, some clinicians have come to rely on blood purification for clinical states where the targeted substance for removal differs from uremic waste products. Over the last decade, a number of studies have emerged to help define the application of extracorporeal blood purification (ECBP) to these "nonuremic" indications. This review describes the application of extracorporeal blood purification in clinical states including sepsis, rhabdomyolysis, congestive heart failure, hepatic failure, tumor lysis syndrome, adult respiratory distress syndrome, intravenous contrast exposure, and lactic acidosis. Additional comments are provided to review existing literature on thermoregulation and osmoregulation, including acute brain injury.

Pyruvate attenuates myoglobin in vitro toxicity

Myoglobinuria is a complication of crush injury as well as substance abuse. This study examined whether pyruvate modified myoglobin in vitro renal toxicity. Renal slices from Fischer-344 rats were incubated for 120 min with 0-12 mg/ml myoglobin. In an initial study, gluconeogenesis was stimulated by the addition of 10 mM pyruvate during the final 30 min. In all other studies, renal slices were incubated with myoglobin in the presence of 0 or 10 mM pyruvate for 120 min. Myoglobin increased lactate dehydrogenase (LDH) release and this was not modified by the presence of pyruvate for the last 30 min of the incubation. Myoglobin toxicity was reduced by coincubation of myoglobin with pyruvate for 120 min. LDH leakage was increased 1.2-, 1.7-, and 1.8-fold above control by 4, 10, and 12 mg/ml myoglobin, compared to 1.2, 1.3, and 1.3 fold in slices coincubated with 10 mM pyruvate, respectively. Myoglobin diminished adenosine triphosphate (ATP) levels but pyruvate maintained a 5x higher level of ATP within the slices. Glucose (10 mM) provided protection only for the low concentration (4 mg/ml) of myoglobin. Myoglobin induced oxidative stress while pyruvate prevented the rise in lipid peroxidation and glutathione disulfides by myoglobin. Myoglobin diminished total glutathione levels in pyruvate-treated tissue, but glutathione levels remained higher than tissues incubated in the absence of pyruvate. These results indicate that pyruvate reduced toxicity by preventing oxidative stress and via a supply of an energy substrate.

Crush syndrome patients after the Marmara earthquake

BACKGROUND

To assess the treatment and outcome of patients with crush injury sustained in the Marmara earthquake.

METHODS

Seven hundred eighty three patients were transferred to a university hospital and 25 of them were admitted to the intensive care unit. The medical records of 18 crush injury patients were retrospectively reviewed.

RESULTS

The major associated injuries were in the lower extremities, upper extremities, and chest. Seven patients underwent fasciotomy and six patients had amputations. Twelve patients required mechanical ventilation. Adult respiratory distress syndrome developed in four patients. Oliguria occurred in eight patients. Hyperkalaemia was seen in six patients and four of them underwent emergency haemodialysis. One patient died because of hyperkalaemia on arrival to the intensive care unit. Renal failure was treated with haemodialysis or haemoperfusion in 13 patients. Five patients died because of multiple organ failure and two patients because of sepsis.

CONCLUSION

Crush syndrome is a life threatening event. The authors believe that early transportation and immediate intensive care therapy would have improved the survival rate.

Contribution of myoglobin-induced increases in vascular resistance to shock decompensation in experimental Crush-syndrome in anesthetized rats

Myoglobin is known to become nephrotoxic when released in greater amounts from skeletal muscle into the general circulation during shock. The present study deals with the question as to whether a myoglobin-induced increase in vascular tone additionally contributes to the detrimental role of this protein in hypovolemic shock. Anesthetized rats were subjected to 250 mg kg x h(-1) myoglobin infused i.v. during hemorrhagic hypotension of 50 mmHg. Shock survival time was measured, as were blood flow and vascular resistance in kidney, intestine, brain, and heart, using the microsphere method. Rats subjected to only myoglobin or hemorrhage survived a period of >120 min; in contrast, rats, exposed to both myoglobin and hemorrhage died at 68 +/- 9 min. When the animals subjected to only hemorrhage and to myoglobin/ hemorrhage were compared, significantly lower values were found in the latter group with respect to blood flow in the kidney (1.7 +/- 0.1 vs. 0.2 +/- 0.05 ml x min(-1) x g(-1)), small intestine (1.0 +/- 0.1 vs. 0.5 +/- 0.1 ml x min(-1) x g(-1)), cardiac output (112 +/- 5 vs. 62 +/- 10 ml(-1) x min(-1) x kg(-1)), and significantly higher values of total peripheral vascular resistance (0.45 +/- 0.02 vs. 0.81 +/- 0.12 mmHg x min x ml(-1) x kg) at 50 min of hypotension. It is assumed that these effects of myoglobin are induced by its ability to scavenge endogenous nitric oxide, because a modified, non-nitrosylable myoglobin was unable to induce such effects. The results support the view that a pathological release of myoglobin into the general circulation causes increases in vascular resistance of vital organs that may contribute to decompensation of tissue supply when occurring in hypovolemic shock.

Renal replacement therapies in the aftermath of the catastrophic Marmara earthquake

BACKGROUND

Renal replacement therapy is of vital importance in the treatment of crush syndrome victims, who are frequently encountered after catastrophic earthquakes. The Marmara earthquake, which struck Northwestern Turkey in August 1999, was characterized by 477 victims who needed dialysis.

METHOD

Within the first week of the disaster, questionnaires containing 63 clinical and laboratory variables were sent to 35 reference hospitals that treated the victims. Information considering the features of dialyses obtained through these questionnaires was submitted to analysis.

RESULTS

Overall, 639 casualties with renal complications were registered, 477 of whom (mean age 32.3 +/- 13.7 years, 269 male) needed dialysis. Among these, 452 were treated by a single dialysis modality (437 intermittent hemodialysis, 11 continuous renal replacement therapy and 4 peritoneal dialysis), while 25 victims needed more than one type of dialysis. In total, 5137 hemodialysis sessions were performed (mean 11.1 +/- 8.0 sessions per patient) and mean duration of hemodialysis support was 13.4 +/- 9.0 days; this duration was shorter in the non-survivors (7.0 +/- 8.7 vs. 10.0 +/- 9.8 days, P = 0.005). Thirty-four victims who underwent continuous renal replacement therapy had higher mortality rates (41.2 vs. 13.7%, P < 0.0001). Only eight victims were treated by peritoneal dialysis, four of whom also required hemodialysis or continuous renal replacement therapy. The mortality rate in the dialyzed victims was 17.2%, a significantly higher figure compared to the mortality rate of the non-dialyzed patients with renal problems (9.3%; P = 0.015).

CONCLUSION

Substantial amounts of dialysis support may be necessary for treating the victims of mass disasters complicated with crush syndrome. Dialyzed patients are characterized by higher rates of morbidity and mortality.

The effect of externally applied subatmospheric pressure on serum myoglobin levels after a prolonged crush/ischemia injury

BACKGROUND

Patients with injuries that cause significant muscle death often develop rhabdomyolysis. The subsequent release and entry of myoglobin into the systemic circulation leads to myoglobinuria, renal injury, and potentially acute renal failure.

METHODS

Large (5 kg) adult rabbits (n = 8) were anesthetized and a 15-kg weight placed on the posterior compartment for 4 hours. After this time, the weight was removed and releasing incisions were made. Subatmospheric pressure (125 mm Hg) was continuously applied to the wounds of four rabbits. Systemic serum samples were obtained at the time of weight removal and at 2, 4, and 8 hours postremoval, and were analyzed for myoglobin content.

RESULTS

Serum myoglobin levels were similar for both groups at the time of weight removal. Serum myoglobin levels demonstrated a progressive increase with time in nontreated animals, and were significantly elevated compared with subatmospheric pressure-treated animals at all time points (p < 0.001).

CONCLUSION

This study shows that application of subatmospheric pressure to an affected body part is associated with lower serum myoglobin levels.

Non-renal indications for continuous renal replacement therapy

While there is clear support for the use of continuous renal replacement therapy (CRRT) in critically ill acute renal failure patients, there are other illnesses without renal involvement where CRRT might be of value. These include sepsis and other inflammatory syndromes such as acute respiratory distress syndrome (ARDS) and cardiopulmonary bypass where removal of inflammatory mediators by hemofiltration is hypothesized to improve outcome. Adsorption appears to be the predominant mechanism of mediator elimination. However, the observed hemodynamic improvement can, at least partially, be attributed to a reduction of body temperature or to fluid removal, and the evidence for a clinically important removal of proinflammatory cytokines remains limited. Continuous and therefore smooth fluid removal may improve organ function in ARDS, after surgery with cardiopulmonary bypass, and in patients with refractory congestive heart failure. Continuous removal of endogenous toxins, eventually combined with intermittent hemodialysis, is probably beneficial in inborn errors of metabolism, severe lactic acidosis, or tumor lysis syndrome.