Prediction of acute renal failure following soft-tissue injury using the venous bicarbonate concentration

Uric acid in predicting the traumatic rhabdomyolysis induced acute kidney injury; a systematic review and meta-analysis

OBJECTIVE

The objective of this systematic review and meta-analysis was to assess the value of uric acid in predicting acute kidney injury caused by traumatic rhabdomyolysis.

METHODS

The search was conducted in MEDLINE, Scopus, Embase and Web of Science until November 1, 2023. Based on the inclusion and exclusion criteria, the articles were included by two independent researchers. Data regarding study design, patient characteristics, number of patients with and without AKI, mean and SD of uric acid and prognostic characteristics of uric acid were extracted from relevant studies. STATA version 17.0 was used to compute pooled measures of standardized mean differences, odds ratios, and diagnostic accuracy. I2 and chi-square tests were used to assess heterogeneity between studies.

RESULTS

We found 689 non-redundant studies, 44 of them were potentially relevant. Six articles met the inclusion criteria and were included in the review. The results of the meta-analysis confirmed that there was a significant correlation between serum uric acid levels and the occurrence of AKI (SMD = 1.61, 95% CI = 0.69 to 2.54, I2 = 96.94%; p value = 0.001). There were no significant publication biases.

CONCLUSION

According to this meta-analysis, uric acid levels could be considered as a predictor of acute kidney injury following traumatic rhabdomyolysis.

Progress in the Diagnostic and Predictive Evaluation of Crush Syndrome

Crush syndrome (CS), also known as traumatic rhabdomyolysis, is a syndrome with a wide clinical spectrum; it is caused by external compression, which often occurs in earthquakes, wars, and traffic accidents, especially in large-scale disasters. Crush syndrome is the second leading cause of death after direct trauma in earthquakes. A series of clinical complications caused by crush syndrome, including hyperkalemia, myoglobinuria, and, in particular, acute kidney injury (AKI), is the main cause of death in crush syndrome. The early diagnosis of crush syndrome, the correct evaluation of its severity, and accurate predictions of a poor prognosis can provide personalized suggestions for rescuers to carry out early treatments and reduce mortality. This review summarizes various methods for the diagnostic and predictive evaluation of crush syndrome, including urine dipstick tests for a large number of victims, traditional and emerging biomarkers, imaging-assisted diagnostic methods, and developed evaluation models, with the aim of providing materials for scholars in this research field.

Falanga: The clinical correlates of surgical outcomes as a result of foot whipping in a resource poor setting

BACKGROUND

Falanga is a punishment that involves hitting the bare soles of a person's feet. The consequences of this punishment may be limb and life-threatening. Post-traumatic acute kidney injury (AKI) secondary to rhabdomyolysis is a well-documented complication. Patients often require prompt surgical intervention and renal replacement therapy (RRT). The clinical and biochemical presentation of these patients and subsequent outcomes are poorly understood.

AIMS

This prospective observational study describes the clinical presentation and effects of foot whipping on patient outcomes.

METHODOLOGY

Prospective data were collected over a one-year period for 135 patients presenting following blunt force assault admitted to a single centre. Presenting clinical characteristics and patient outcomes were recorded and correlations between presenting clinical characteristics and surgical and clinical outcomes were assessed.

RESULTS

Of 138 patients presenting following blunt force assault 96% were male with a mean age of 28.8 ± 8.01. Thirty-six out of the 138 patients presenting following blunt force assault had received foot-whipping only (falanga group, FG). Ten of these 36 patients in the FG group required surgical intervention, with one requiring a below knee amputation, compared with only two patients who required surgical intervention in the group who experienced blunt force trauma not restricted to foot whipping (Sjambok group). Average length of stay was 4 days (range 2-38) in FG group compared with 5 (range 1-21) in SG group, with no mortalities in either group. For patients in the FG, Hb was higher at presentation compared to patients in the SG group (135.2 33.7 vs 124.2 21.3, p = 0.03) and correlated positively with the need for surgical intervention (r = 0.6, p < 0.01). In this same group, the presenting characteristics of CK (4251.3 3087.4, p = 0.1 vs 7422.6 12347.7, p = 0.1) and urine output (0.95 0.4 vs 0.7 0.4) positively correlated with RRT [CK r = 0.6, p < 0.01, UO r = 0.46, p < 0.01].

CONCLUSION

Patients who present following falanga frequently require surgical intervention and the related healthcare utilisation and morbidity is high. Clinical indicators of a greater systemic injury at presentation may correlate with an increased likelihood of requiring surgical intervention or RRT.

Admission serum myoglobin and the development of acute kidney injury after major trauma

BACKGROUND

Myoglobin and creatine kinase (CK) are both established markers of muscle injury but their hospital admission values have never been compared to predict post-traumatic acute kidney injury (AKI).

METHODS

An observational registry study of consecutive trauma patients admitted to a major regional trauma centre. The primary outcome was stage 1 or more AKI in the first 7 days after trauma. We assessed the association of hospital admission myoglobin or CK with development of AKI both alone and when added to two existing risk prediction models for post traumatic AKI.

RESULTS

Of the 857 trauma patients (median age 36 [25-52], 96% blunt trauma, median ISS of 20 [12-47]) included, 102 (12%) developed AKI. Admission myoglobin performed better than CK to predict AKI any stage with an AUC-ROC of 0.74 (95% CI 0.68-0.79) and 0.63 (95% CI 0.57-0.69), respectively (p < 0.001). Admission myoglobin also performed better than CK to predict AKI stage 2 or 3 [AUC-ROC of 0.79 (95% CI 0.74-0.84) and 0.74 (95% CI 0.69-0.79), respectively (p < 0.001)] with a best cutoff value of 1217 µg/L (sensitivity 74%, specificity 77%). Admission myoglobin added predictive value to two established models of AKI prediction and showed significant ability to reclassify subjects regarding AKI status, while admission CK did not. Decision curve analysis also revealed that myoglobin added net benefit to established predictive models. Admission myoglobin was better than CK at predicting development of significant rhabdomyolysis.

CONCLUSIONS

Admission myoglobin better predicts the development of AKI and severe rhabdomyolysis after major trauma. Admission myoglobin should be added in established predictive models of post-traumatic AKI to early identify high-risk patients.

A "crush" course on rhabdomyolysis: risk stratification and clinical management update for the perioperative clinician

Rhabdomyolysis, the release of myoglobin and other cellular breakdown products from necrotic muscle tissue, is seen in patients with crush injuries, drug overdose, malignant hyperthermia, muscular dystrophy, and with increasing frequency in obese patients undergoing routine procedures. For the perioperative clinician, managing the resultant shock, hyperkalemia, acidosis, and myoglobinuric acute kidney injury can present a significant challenge. Prompt recognition, hydration, and correction of metabolic disturbances may reduce or eliminate the need for long-term renal replacement therapy. This article reviews the pathophysiology and discusses key issues in the perioperative diagnosis, risk stratification, and management of rhabdomyolysis.

Buffers Strongly Modulate Fibrin Self-Assembly into Fibrous Networks

Fibrin is a plasma protein with a central role in blood clotting and wound repair. Upon vascular injury, fibrin forms resilient fibrillar networks (clots) via a multistep self-assembly process, from monomers, to double-stranded protofibrils, to a branched network of thick fibers. In vitro, fibrin self-assembly is sensitive to physicochemical conditions like the solution pH and ionic strength, which tune the strength of the noncovalent driving forces. Here we report a surprising finding that the buffer-which is necessary to control the pH and is typically considered to be inert-also significantly influences fibrin self-assembly. We show by confocal microscopy and quantitative light scattering that various common buffering agents have no effect on the initial assembly of fibrin monomers into protofibrils but strongly hamper the subsequent lateral association of protofibrils into thicker fibers. We further find that the structural changes are independent of the molecular structure of the buffering agents as well as of the activation mechanism and even occur in fibrin networks formed from platelet-poor plasma. This buffer-mediated decrease in protofibril bundling results in a marked reduction in the permeability of fibrin networks but only weakly influences the elastic modulus of fibrin networks, providing a useful tuning parameter to independently control the elastic properties and the permeability of fibrin networks. Our work raises the possibility that fibrin assembly in vivo may be regulated by variations in the acute-phase levels of bicarbonate and phosphate, which act as physiological buffering agents of blood pH. Moreover, our findings add a new example of buffer-induced effects on biomolecular self-assembly to recent findings for a range of proteins and lipids.

Critical Care Management of Bariatric Surgery Complications

Obesity remains a major medical disease that often requires surgical intervention in morbidly obese patients. Surgical procedures have evolved and are performed routinely in most major medical centers. Outcomes are often dependent on patient characteristics, type of procedure, and preoperative planning. Risk stratification often depends on screening and optimizing known comorbidities often encountered in this patient population. A thorough understanding of the physiologic changes seen in obese patient and the commonly performed operations will allow the physician to perform optimal treatment strategies.

Prevention of kidney injury following rhabdomyolysis: a systematic review

OBJECTIVE

To conduct a systematic literature review to evaluate evidence-based recommendations for the prevention of rhabdomyolysis-associated acute renal failure (ARF).

DATA SOURCES

PubMed (1966-December 2012), International Pharmaceutical Abstracts, Science Citation Index, and Cochrane databases (1970-December 2012) were searched. There were no language restrictions.

STUDY SELECTION AND DATA EXTRACTION

Studies selected dealt with treatment of rhabdomyolysis (crush syndrome) or prevention of ARF in patients with rhabdomyolysis. Articles excluded did not present original data or described only the management of ARF after it developed. Single case reports were excluded. Extracted data included study type; population; definitions of rhabdomyolysis and ARF; fluid, sodium bicarbonate, and mannitol dosages; and study findings.

DATA SYNTHESIS

Twenty-seven studies met the inclusion criteria. No controlled trials compared intravenous fluid administration plus sodium bicarbonate to fluid administration alone. Three concluded that there was no significant difference in the rates of ARF between patients receiving and those not receiving sodium bicarbonate; however, urine alkalinization was not documented. Eight investigations concluded that delayed fluid administration increased the risk of ARF. No controlled study compared volumes of fluid administered or targeted urine output goals. Fluid type, therapy duration, and monitoring parameters varied widely; 4 used a urine output goal in adults of more than 300 mL/h or 300 mL/h or more. No evidence supported a preferred fluid type or that sodium bicarbonate with or without mannitol was superior to fluid therapy alone.

CONCLUSIONS

Intravenous fluids should be initiated as soon as possible, preferably within the first 6 hours after muscle injury, at a rate that maintains a urine output in adults of 300 mL/h or more for at least the first 24 hours. Sodium bicarbonate should be administered only if necessary to correct systemic acidosis and mannitol only to maintain urine output of 300 mL/h or more despite adequate fluid administration.

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.

Utility of urine myoglobin for the prediction of acute renal failure in patients with suspected rhabdomyolysis: a systematic review

BACKGROUND

Urine myoglobin continues to be used as a marker of rhabdomyolysis, particularly to assess risk of developing acute renal failure and evaluate treatment success. We sought to determine the predictive validity of urine myoglobin (uMb) for acute renal failure (ARF) in patients with suspected rhabdomyolysis.

METHODS

We performed a broad systemic review of the literature from January 1980 to December 2006 using the search terms myoglobin$ AND (renal OR ARF OR kidney). Only primary studies published in English where uMb measurement was related to ARF were included.

RESULTS

Of 1602 studies screened, 52 met all selection criteria. The studies covered a wide spectrum of etiologies for rhabdomyolysis, dissimilar diagnostic criteria for ARF and rhabdomyolysis, and various methods of uMb measurement and were mostly case series (n = 32). There was poor reporting on the uMb method, and 17 studies failed to provide any information about the method. The reporting of clinical criteria for ARF with respect to timing, description, performance, and interpretation also lacked adequate detail for replication. Eight studies (total 295 patients) had data for 2-by-2 tables. Sensitivity of the uMb test was 100% in 5 of the 8 studies, specificity varied widely (15% to 88%), and CIs around these measures were high. Pooling of data was not possible because of study heterogeneity.

CONCLUSIONS

There is inadequate evidence evaluating the use of uMb as a predictor of ARF in patients with suspected rhabdomyolysis.

Predicting hospital-acquired acute kidney injury--a case-controlled study

Acute kidney injury is a major complication of hospitalization, occurring in 5-7 percent of hospitalized patients. The patient characteristics and prognostic variables that help predict acute kidney injury have not been studied in the general hospitalized population. The objectives of this study are to derive and validate a predictive score for hospital-acquired acute kidney injury (HAKI). We conducted a case-controlled study of HAKI involving 180 cases and 360 controls. A multivariate logistic regression model was developed in two-thirds of the subjects and validated in the other third. Upon admission, cases in the developmental sample were older (67 vs. 63 yrs, p = .008) and more likely to have diabetes (51% vs. 35%; p = .003), hypertension (77% vs. 60%, p = .001), heart failure (34% vs. 20%, p = .004), blood urea nitrogen >or=25 mg/dL (38% vs. 20%, p = <.001), creatinine >or=1.1 mg/dL (65% vs. 39%; p <.001), albumin <or=4 g/dL (85% vs. 71%; p = .033), and bicarbonate <24 mEq/L or >30 mEq/L (42% vs. 29%; p = .05) compared to controls. The final risk score included pulse, bicarbonate, creatinine, and specific medications (NSAIDs, ACE inhibitors, ARBs, and/or diuretics). The c-statistic for the risk score in the developmental sample was 0.69. In the validation sample, an increasing number of risk factors was associated with increased risk of HAKI (16% and 62% in the low and high-risk groups, respectively). In conclusion, a simple model based on readily available data stratifies patients according to their risk of developing HAKI and may guide clinical decision making and provide a basis for further research into HAKI.

Rhabdomyolysis: diagnosis and treatment in bariatric surgery

BACKGROUND

Rhabdomyolysis (RML) and subsequent acute renal failure can be serious problems following bariatric operations. Early diagnosis and treatment are important to avoid the complications of RML.

METHODS

This review was achieved by searching the key words: Rhabdomyolysis, diagnosis, treatment and bariatric surgery. We included prospective, retrospective, case reports and review articles.

RESULTS

RML diagnosis can be done by: signs and symptoms, physical evaluation, laboratory findings and imaging examinations. Muscle weakness, myalgia, decubitus ulcer, proteinuria and myoglobinuria are the more mentioned findings. Elevation of CPK levels is the most sensitive diagnostic evidence of RML. Treatment is geared toward preserving renal function by avoiding dehydration, hypovolemia, tubular obstruction, aciduria, and free radical release. Early recognition allows the administration of fluids, bicarbonate, and mannitol.

CONCLUSION

Prophylactic measures and early diagnosis and treatment of rhabdomyolysis in bariatric surgery are imperative to prevent the potential fatal complications of this condition.

Altered Regulation of type 3 Na+/H+exchanger, type 1 Na+/HCO3-cotransporter, and Na+,K+-ATPase in the Kidney of Rats with Experimental Rhabdomyolysis

Metabolic acidosis was shown to correlate with deterioration of renal function in patients with rhabdomyolysis. The present study was aimed to investigate whether the changes of type 3 Na⁺/H⁺ exchanger (NHE3), type 1 Na⁺/HCO₃^- cotransporter (NBC1), and Na⁺,K⁺-ATPase α1 subunit may play a role in the pathogenesis of metabolic acidosis in glycerol-induced experimental rhabdomyolysis. Male Sprague-Dawley rats were deprived of fluid intake for 24 hours, and then were injected with 50% glycerol in normal saline (10 mL/kg, intramuscularly). At 24 hours after the glycerol injection, rats were sacrificed by decapitation. Control rats were injected with normal saline. The protein expression of NHE3, NBC1 and Na⁺,K⁺-ATPase α1 subunit was determined in the cortex of the kidney by immunoblotting and immunohistochemistry. Following the treatment of glycerol, creatinine clearance was significantly decreased, and high anion gap metabolic acidosis developed. In the experimental group, the expression of Na⁺,K⁺-ATPase α1 subunit was significantly decreased in the cortex of the kidney. On the contrary, the expression of NHE3 and NBC1 was significantly increased. Immunohistochemical analyses confirmed the immunoblotting data. In conclusion, the coordinate up-regulation of NHE3 and NBC1 may play an adaptive role against the metabolic acidosis in glycerol-induced rhabdomyolysis.

Factors predictive of acute renal failure and need for hemodialysis among ED patients with rhabdomyolysis

OBJECTIVE

We assessed the primary causes of rhabdomyolysis, the factors associated with the development of acute renal failure (ARF), and the need for hemodialysis (HD) among a series of patients presenting to an urban emergency department with rhabdomyolysis.

METHODS

A chart review between January 1992 and December 1995 was conducted of patients aged 18 years or older with a diagnosis of rhabdomyolysis and an initial serum creatine phosphokinase greater than 1000 U/L. Patients were excluded if they had evidence of myocardial ischemia, cerebrovascular insufficiency, or the development of rhabdomyolysis after hospitalization. Demographic information, presumed causative factors, past medical history, medication usage, and laboratory data were collected.

RESULTS

Ninety-seven patients (93 men, 4 women) were enrolled, with a mean age of 35.7 years. The most common causes of rhabdomyolysis were cocaine (30), exercise (29), and immobilization (18). Seventeen of 97 (17.5%) patients developed ARF; 8 patients (8.25%) needed HD. Several clinical and laboratory factors were statistically associated with development of ARF and need for HD. The only variable that was predictive of both ARF and need for HD in separate multivariate regression models was the initial creatinine (Cr). Initial blood urea nitrogen also was predictive of the need for HD. No patient developed ARF with an initial Cr less than 1.7 mg/dL.

CONCLUSION

Acute renal failure and need for HD are common complications of rhabdomyolysis. Except for initial serum Cr and blood urea nitrogen, clinical and laboratory factors were not reliable predictors for the development of ARF or need for HD.

Validation of an outcome prediction model for critically ill trauma patients without head injury

BACKGROUND

The Acute Physiology and Chronic Health Evaluation (APACHE) II system is inaccurate in predicting the risk of death in trauma patients, especially those without head injury. Using multivariate analysis of the APACHE II system in a development set, a new predictive equation was modeled. The four variables that were independently associated with mortality were PaO2/FiO2 ratio, mean arterial pressure, temperature, and the need for inotropic support. This model was tested prospectively in an independent validation set of 300 patients.

METHODS

Risk of death was calculated using the APACHE II system with the diagnostic category of multiple trauma and weighting for operative intervention as required. The new model was similarly assessed using the four predictor variables and their beta-coefficients for each mechanism of injury and the entire group. The predicted risk of death derived by both models was compared with the observed mortality rate. Discrimination was calculated using a 2 x 2 decision matrix with a decision threshold of r = 0.5 and receiver operating characteristic curves. Calibration was assessed graphically and by statistical correlation.

RESULTS

The observed mortality rate was 28.3% and the predicted mortality risk was 27.4% for the model and 6.26% for APACHE II. The sensitivity and specificity of the model were 58.8 and 90.7%, and the sensitivity and specificity of APACHE II were 1.2 and 100%. The areas under the receiver operating characteristic curves were 0.84 and 0.78 for the model and the APACHE II system, respectively. Calibration of the model was superior within all deciles of risk (model, R2 = 0.93, p < 0.001; APACHE II, R2 = 0.82, p = 0.02).

CONCLUSION

The model accurately predicted the risk of death for the entire group. It is superior to the APACHE II system and is the highest reported sensitivity for 24-hour intensive care unit predictive models that have been applied to the critically injured.

Torture rhabdomyorhexis--a pseudo-crush syndrome

Two patients who were systematically tortured and deprived of any oral intake presented with acute renal failure several days later. Unlike the classical crush syndrome, we describe a clinical entity wherein repeated direct muscle injury from blunt trauma, in addition to forced dehydration, led to myoglobinuria and renal failure. The literature is reviewed, and biochemical indices predicting severity of injury, pathophysiology, and management protocol are described. This pseudo-crush syndrome caused by rhabdomyorhexis in addition to rhabdomyolysis is an unusual entity, in part related to extreme sociopolitical factors.