Disaster nephrology: a new concept for an old problem

Kidney Care in Times of Crises: A Review

The global burden of kidney disease is increasing, paralleled by a rising number of natural and man-made crises. During these tumultuous times, accessing vital healthcare resources becomes challenging, posing significant risks to individuals, particularly those with kidney disease. This review delves into the impact of crises on kidney disease, with a particular focus on acute kidney injury (AKI), kidney failure (KF), and kidney transplant (KT). Patients experiencing crush injuries leading to AKI may encounter delayed diagnosis due to the chaotic nature of disasters and limited availability of resources. In chronic crises, such as conflicts, patients with KF are particularly affected, and deviations from dialysis standards are unfortunately common, impacting morbidity and mortality rates. Additionally, crises also disrupt access to kidney transplants, potentially compromising transplant outcomes. This review underscores the critical importance of preparedness measures and proactive management for kidney disease in crisis settings. Collaborative efforts among government bodies, rescue teams, healthcare providers, humanitarian agencies, and nongovernmental organizations are imperative to ensure equitable and reasonable care for kidney disease patients during times of crises, with the aim of saving lives and improving outcomes.

2023 catastrophic Turkey earthquake: clinical outcomes of pediatric patients rescued under the rubble

OBJECTIVES

Children are the most vulnerable population affected by the earthquake. We aimed to examine the characteristics, morbidity, mortality, and the factors affecting these pediatric earthquake victims to guide the follow-up of pediatric patients who were rescued under the rubble in possible future disasters.

METHODS

This is a retrospective observational study. The files of pediatric earthquake victims aged 0-18 years who were admitted to Adana City Training and Research Hospital between 6 February-30 April 2023 were analyzed. 318 patients were included in the study.

RESULTS

Of all patients 48.7% (n = 155) were female and 51.3% (n = 163) were male. The mean age of the patients was 114.8 months. 65.4% (n = 208) of the patients were discharged from our hospital, eighteen patients (5.7%) died. Information on the hour when the patients were rescued under the rubble could be reached in 117 (36.8%) patients. The mean rescue time of these patients was 50.5 hours. 62 (53%) victims were rescued in the first 24 hours after the earthquake. There were 111 patients (34.9%) with fractures. There were 118 patients (37.1%) who underwent fasciotomy surgery. The total number of patients with amputation was 48 (15.1%). There were 36 patients (11.3%) with one limb amputated, 12 patients (%3.7) with more than one limb amputation. Internal organ injury was present in 30.5% (n = 97) of the patients. Of these patients, 85.6% (n = 83) had single organ trauma and 14.4% (n = 14) had multiple organ trauma. There were 58 patients (18.2%) with acute renal failure in follow-up. The mean rescue time for patients with amputation was 83.65 ± 62.9 hours, and for patients without amputation was 36.44 ± 50.6 hours. This difference was statistically significant (p = 0.001). No statistically significant difference was found when the ages of the patients were compared to fasciotomy, amputation, and fracture status.

CONCLUSION

While evaluating earthquake-induced trauma, pediatric patients should be approached carefully.

Resilience and challenges of peritoneal dialysis survivors in the aftermath of the 2023 Kahramanmaraş earthquake

INTRODUCTION

Peritoneal dialysis (PD) remains understudied in disaster nephrology. This retrospective multicenter study explores the experiences of PD survivors following the February 6, 2023, Kahramanmaraş Earthquake.

METHODS

Adult PD patients from 11 affected cities were analyzed to assess challenges faced during and postearthquake, alongside clinical outcomes.

RESULTS

Among 101 participants (median age: 45 years, median PD duration: 24 months), 57 were female, with 79 on continuous ambulatory PD. Challenges included power outages and water shortages, with primary shelter in kin's houses (33%) and homes (28%). Twelve patients experienced PD program delays, and three lacked assistance postdisaster. Sixteen patients changed PD modalities, with seven experiencing postearthquake peritonitis. Clinical parameters remained stable, except for a slight decrease in hemoglobin levels.

CONCLUSION

Despite challenges, PD survivors exhibited resilience, highlighting the importance of addressing peritonitis and unusual pathogens in disaster preparedness initiatives.

The Revival of Sorbents in Chronic Dialysis Treatment

Interest in the use of sorbents in chronic dialysis treatment has undergone a revival in the last decades, for which two major factors are responsible. The first is the potential of sorbents as adjunct therapy for the removal of substances that are difficult to remove by conventional dialysis therapies. The second is their use in regeneration of dialysate, which is of pivotal importance in the design of portable or even wearable treatments, next to the potential for reducing water use during conventional dialysis treatment. Sorbent-enhanced dialysis with synthetic polymers was associated with a reduction in inflammatory parameters as compared to hemodialysis and even associated with improved survival in smaller studies, although this needs to be confirmed in large randomized trials. Incorporation of sorbents within a dialysis membrane (mixed matrix membrane) appears a promising way forward to reduce the complexity and costs of a dual therapy but needs to be tested in vivo. For regeneration of dialysate, at present, a combination of urease, zirconium-based sorbents, and activated charcoal is used. Next to sodium release by the sorbent in exchange for ammonium and the CO2 release by the hydrolysis of urea has been a bottleneck in the design of wearable devices, although short-term trials have been performed. Still, for widespread and flexible application of sorbent-assisted portable or wearable devices, a direct urea sorbent would be a major asset. In the near future, it will likely become apparent whether sorbent-assisted dialysis techniques are feasible for routine implementation in clinical practice.

Crush Syndrome of Children in Kahramanmaraş Earthquake: A Single Center Experience in Malatya

OBJECTIVE

Natural disasters cause enormous environmental, economic, and human losses. Children are the most vulnerable group and face severe consequences. While the primary cause of post-traumatic death is direct injury, the secondary cause is crush syndrome (CS). In this study, we aimed to share our experience in the management of children with CS during disasters by evaluating the clinical and laboratory outcomes of a group of 26 paediatric patients.

MATERIALS AND METHODS

Age, weight, length of time under rubble, laboratory results, and characteristics of crush injuries were assessed in 26 paediatric patients admitted to the emergency department after the earthquake. Diagnostic criteria for CS were established and the need for dialysis, hyperbaric oxygen or amputation and its determinants were assessed.

RESULTS

Crush syndrome was observed in 10 of the 26 patients. Significant differences in creatinine, aspartate aminotransferase, alanine aminotransferase, creatine kinase, hematocrit, pH, HCO3, and myoglobin levels were observed between patients with and without CS. None of the individuals rescued from the rubble within the first 6 hours had symptoms associated with CS. These 10 patients who developed CS were rescued within the first 48 hours of the earthquake, while 2 siblings were rescued after 81 hours and did not develop CS.

CONCLUSION

The fact that the children were rescued from the rubble after 81 hours without developing CS shows the importance of patience in rescue operations. In addition, the very cold weather conditions during this earthquake may have prevented the development of dehydration and acute kidney injury and reduced the possibility of CS.

BREAKING NEW GROUND: STANDARDIZING RAT MODELS FOR CRUSH SYNDROME INVESTIGATIONS

ABSTRACT

Crush syndrome (CS), alternatively termed traumatic rhabdomyolysis, is a paramount posttraumatic complication. Given the infeasibility of conducting direct simulation research in humans, the role of animal models is pivotal. Regrettably, the dearth of standardized animal models persists. The objective of this study was to construct a repeatable standardized rat CS models and, based on this, simulate specific clinical scenarios. Methods: Using a self-developed multichannel intelligent small-animal crush injury platform, we applied a force of 5 kg to the hind limbs of 8-week-old rats (280-300 g), subjecting them to a continuous 12 h compression to establish the CS model. Continuous monitoring was conducted for both the lower limbs and the overall body status. After decompression, biochemical samples were collected at 3, 6, 12, and 24 h. In addition, we created a CS model after resection of the left kidney (UNx-CS), which was conceptualized to simulate a more challenging clinical scenario to investigate the physiological and pathological responses rats with renal insufficiency combined with crush injury. The results were compared with those of the normal CS model group. Results : Our experiments confirm the stability of the crush injury platform. We defined the standardized conditions for modeling and successfully established rats CS model in bulk. After 12 h of compression, only 40% of the rats in the CS group survived for 24 h. Systemically, there was clear evidence of insufficient perfusion, reflecting the progression of CS from localized to generalized. The injured limbs displayed swelling, localized perfusion deficits, and severe pathological alterations. Significant changes were observed in blood biochemical markers: aspartate transaminase, lactate dehydrogenase, K+, creatine kinase, creatinine, and blood urea nitrogen levels rose rapidly after decompression and were significantly higher than the sham group. The kidney demonstrated characteristic pathological changes consistent with established CS diagnostic criteria. Although the UNx-CS rat model did not exhibit significant biochemical differences and pathological scores when compared with the standard CS model, it did yield intriguing results with regard to kidney morphology. The UNx-CS group manifested a higher incidence of cortical and medullary protein casts compared with the NC-CS group. Conclusion: We developed and iteratively refined a novel digital platform, addressing the multiple uncontrollable variables that plagued prior models. This study validated the stability of the platform, defined the standardized conditions for modeling and successfully established the CS model with good repeatability in bulk. In addition, our innovative approach to model a clinically challenging scenario, the UNx-CS rat model. This offers an opportunity to delve deeper into understanding the combined effects of preexisting renal compromise and traumatic injury. In summary, the development of a standardized, reproducible CS model in rats represents a significant milestone in the study of Crush syndrome. This study is of paramount significance as it advances the standardization of the CS model, laying a solid foundation for subsequent studies in related domains, especially in CS-AKI.

Factors predicting kidney replacement therapy in pediatric earthquake victims with crush syndrome in the first week following rescue

Crush syndrome due to traumatic rhabdomyolysis is one of the most significant problems to occur following earthquakes. On February 6, 2023, millions of people in Turkey were affected by two consecutive Kahramanmaraş earthquakes. The present study reports the analysis of clinical and laboratory findings of crush syndrome in pediatric earthquake victims admitted to our hospital from our region where the earthquake had a devastating effect. Clinical and laboratory findings concerning earthquake victims with crush syndrome were analyzed within the first week to determine what factors are predictive of kidney replacement therapy (KRT). The data of patients were retrospectively collected from medical records. A total of 310 children were admitted as earthquake victims to the pediatric emergency department. Ninety-seven (31%) of these patients had crush syndrome. Fifty-three (55%) of those with crush syndrome were female. The mean age was 10.9 ± 4.7 years, and the mean time under the rubble was 30.6 ± 23.8 h. Twenty-two patients (23%) required KRT. Hemodialysis was applied to 16 (73%) of them, and hemodiafiltration was applied to the other six (27%) in the pediatric intensive care unit. Regarding creatine kinase (CK) levels, the area under the receiver operating characteristic (ROC) curve (AUC) for predicting KRT was 0.905 (95% confidence interval [CI] 0.848-0.963; p < 0.001). The optimal cut-off value was 40,000 U/L with a sensitivity of 86% and a specificity of 83%. In terms of the percentage of body area crushed, the AUC for predicting KRT was 0.907 (95% CI 0.838-0.976; p < 0.001). The optimal cut-off value was 30% with a sensitivity of 86% and a specificity of 88%. Multiple logistic regression analysis showed that each 10% increase in body area crushed (OR 4.16, 95% CI 1.58-10.93, p = 0.004) and 1 mg/dl increase in the serum phosphorus level (OR 4.19, 95% CI 1.71-10.28, p = 0.002) were significant risk factors for dialysis treatment.

CONCLUSIONS

Crush syndrome and kidney problems are common following disasters like earthquakes. Clinical and laboratory findings at admission can predict dialysis requirement in earthquake victims. While CK elevation, body area crushed percentage, and increased phosphorus level were predictive of dialysis treatment, time under the rubble was not. Even if the patients were under the rubble for a short time, acute kidney injury (AKI) may develop as a result of severe hypovolemia due to crush injuries, and patients may need KRT.

WHAT IS KNOWN

•Crush syndrome after earthquakes needs to be treated carefully in victims and can cause AKI and mortality when not treated timely and appropriately.

WHAT IS NEW

•CK level elevation, body area crushed percentage, and increased phosphorus level are predictive of dialysis treatment. •The time under the rubble may not be predictive of dialysis requirement.

Destructive disasters, trauma, crush syndrome, and beyond

Orthopedic injuries, especially fractures of long bones as well as multiple fractures and comminuted fractures, are very common after destructive disasters (e.g., earthquakes, wars, and hurricanes). Another frequent problem is traumatic rhabdomyolysis, which may result in crush syndrome, the second most frequent cause of death after direct traumatic impact following earthquakes. To improve outcomes, interventions should be initiated even before extrication of the victims, which include maintenance of airway patency and spine stabilization, stopping traumatic bleeding by any means, and initiating fluid resuscitation. On-site amputations have been extensively debated to liberate the victims if the release of trapped limbs is impossible. Early after the rescue, a primary survey and triage are performed, a fluid resuscitation policy is planned, complications are treated, the wounds are decontaminated, and the victim is transported to specialized hospitals. A triage and primary survey are also performed at admission to the hospitals, which are followed by a secondary survey, physical, laboratory, and imaging examinations. Washing and cleaning of the soft-tissue injuries and debridement in open, necrotic wounds are vital. Applications of fasciotomies and amputations are controversial since they are associated with both benefits and serious complications; therefore, clear indications should be defined. Crush syndrome has been described as the presence of systemic manifestations following traumatic rhabdomyolysis, the most important component of which is acute kidney injury that may contribute to fatal hyperkalemia. The overall mortality rate is around 20% in crushed patients, which underlines the importance of prevention. Treatment includes maintaining of fluid electrolyte and acid-base balance, application of dialysis, and also prevention and treatment of complications. The principles and practices in disaster medicine may differ from those applied in routine practice; therefore, organizing repeated training courses may be helpful to provide the most effective healthcare and to save as many lives as possible after mass disasters.

Disasters and kidney care: pitfalls and solutions

Patients with kidney disease, especially those with kidney failure, are particularly susceptible to the adverse effects of disasters because their survival depends on functional infrastructure, advanced technology, the availability of specific drugs and well-trained medical personnel. The risk of poor outcomes across the entire spectrum of patients with kidney diseases (acute kidney injury, chronic kidney disease and kidney failure on dialysis or with a functioning transplant) increases as a result of disaster-related logistical challenges. Patients who are displaced face even more complex problems owing to additional threats that arise during travel and after reaching their new location. Overall, risks may be mitigated by pre-disaster preparedness and training. Emergency kidney disaster responses depend on the type and severity of the disaster and include medical and/or surgical treatment of injuries, treatment of mental health conditions, appropriate diet and logistical interventions. After a disaster, patients should be evaluated for problems that were not detected during the event, including those that may have developed as a result of the disaster. A retrospective review of the disaster response is vital to prevent future mistakes. Important ethical concerns include fair distribution of limited resources and limiting harm. Patients with kidney disease, their care-givers, health-care providers and authorities should be trained to respond to the medical and logistical problems that occur during disasters to improve outcomes.

Prehospital management of earthquake crush injuries: A collective review

Earthquakes are natural disasters which can destroy the rural and urban infrastructure causing a high toll of injuries and death without advanced notice. We aim to review the prehospital medical management of earthquake crush injuries in the field. PubMed was searched using general terms including rhabdomyolysis, crush injury, and earthquake in English language without time restriction. Selected articles were critically evaluated by three experts in disaster medicine, emergency medicine, and critical care. The medical response to earthquakes includes: (1) search and rescue; (2) triage and initial stabilization; (3) definitive care; and (4) evacuation. Long-term, continuous pressure on muscles causes crush injury. Ischemia-reperfusion injury following the relieving of muscle compression may cause metabolic changes and rhabdomyolysis depending on the time of extrication. Sodium and water enter the cell causing cell swelling and hypovolemia, while potassium and myoglobin are released into the circulation. This may cause sudden cardiac arrest, acute extremity compartment syndrome, and acute kidney injury. Recognizing these conditions and treating them timely and properly in the field will save many patients. Majority of emergency physicians who have worked in the field of the recent Kahramanmaraş 2023, Turkey, earthquakes, have acknowledged their lack of knowledge and experience in managing earthquake crush injuries. We hope that this collective review will cover the essential knowledge needed for properly managing seriously crushed injured patients in the earthquake field.

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.

Lessons learned during the war in Ukraine: a report from the Renal Disaster Relief Task Force of the ERA

People living with kidney disease are among the most vulnerable at times of natural or man-made disasters. In addition to their unpredictable course, armed conflicts impose a major threat given the disruption of infrastructure, sanitation and access to food, water and medical care. The ongoing war in Ukraine has once more demonstrated the importance of preparedness, organization, coordination and solidarity during disasters. People living with kidney disease face serious challenges given their dependence on life-sustaining treatment, irrespective of whether they remain in the war zone or are displaced internally or externally. This especially affects those requiring kidney replacement therapy, dialysis or transplantation, but also patients with other kidney diseases and the medical staff who care for them. Soon after the war started, the European Renal Association assigned a Renal Disaster Relief Task Force dedicated to support the people living with kidney disease and the nephrology community in Ukraine. This report summarizes the major challenges faced, actions taken and lessons learned by this task force. We anticipate that the experience will help to increase preparedness and mitigate the devastating effects of armed conflicts on the kidney community in the future and propose to establish an international collaboration to extend this effort to other parts of the world facing similar challenges.

Precision engineered peptide targeting leukocyte extracellular traps mitigate acute kidney injury in Crush syndrome

Crush syndrome induced by skeletal muscle compression causes fatal rhabdomyolysis-induced acute kidney injury (RIAKI) that requires intensive care, including hemodialysis. However, access to crucial medical supplies is highly limited while treating earthquake victims trapped under fallen buildings, lowering their chances of survival. Developing a compact, portable, and simple treatment method for RIAKI remains an important challenge. Based on our previous finding that RIAKI depends on leukocyte extracellular traps (ETs), we aimed to develop a novel medium-molecular-weight peptide to provide clinical treatment of Crush syndrome. We conducted a structure-activity relationship study to develop a new therapeutic peptide. Using human peripheral polymorphonuclear neutrophils, we identified a 12-amino acid peptide sequence (FK-12) that strongly inhibited neutrophil extracellular trap (NET) release in vitro and further modified it by alanine scanning to construct multiple peptide analogs that were screened for their NET inhibition ability. The clinical applicability and renal-protective effects of these analogs were evaluated in vivo using the rhabdomyolysis-induced AKI mouse model. One candidate drug [M10Hse(Me)], wherein the sulfur of Met10 is substituted by oxygen, exhibited excellent renal-protective effects and completely inhibited fatality in the RIAKI mouse model. Furthermore, we observed that both therapeutic and prophylactic administration of M10Hse(Me) markedly protected the renal function during the acute and chronic phases of RIAKI. In conclusion, we developed a novel medium-molecular-weight peptide that could potentially treat patients with rhabdomyolysis and protect their renal function, thereby increasing the survival rate of victims affected by Crush syndrome.

Management of pediatric dialysis and kidney transplant patients after natural or man-made disasters

Pediatric patients on kidney replacement therapy (KRT) are among the most vulnerable during large-scale disasters, either natural or man-made. Hemodialysis (HD) treatments may be impossible because of structural damage and/or shortage of medical supplies, clean water, electricity, and healthcare professionals. Lack of peritoneal dialysis (PD) solutions and increased risk of infectious/non-infectious complications may make PD therapy challenging. Non-availability of immunosuppressants and increased risk of infections may result in graft loss and deaths of kidney transplant recipients. Measures to mitigate these risks must be considered before, during, and after the disaster including training of staff and patients/caregivers to cope with medical and logistic problems. Soon after a disaster, if the possibility of performing HD or PD is uncertain, patients should be directed to other centers, or the duration and/or number of HD sessions or the PD prescription adapted. In kidney transplant recipients, switching among immunosuppressants should be considered in case of non-availability of the medications. Post-disaster interventions target treating neglected physical and mental problems and also improving social challenges. All problems experienced by pediatric KRT patients living in the affected area are applicable to displaced patients who may also face extra risks during their travel and also at their destination. The need for additional local, national, and international help and support of non-governmental organizations must be anticipated and sought in a timely manner.

The impact of Hurricane Maria on individuals living with non-communicable disease in Puerto Rico: the experience of 10 communities

Background

Coinciding with the rising non-communicable disease (NCD) prevalence worldwide is the increasing frequency and severity of natural hazards. Protecting populations with NCDs against natural hazards is ever more pressing given their increased risk of morbidity and mortality in disaster contexts. This investigation examined Hurricane Maria’s impacts across ten lower SES municipalities in Puerto Rico with varying community characteristics and hurricane impacts to understand experiences of supporting individuals with NCD management in the six-month period following the hurricane.

Methods

We conducted 40 qualitative interviews with mayors, first responders, faith leaders, community leaders, and municipal employees from 10 municipalities in Puerto Rico. Using QSR NVivo software, we deductively and inductively coded interview transcripts and undertook thematic analysis to characterize community-level hurricane impact and consequences for NCD management, and to identify convergent and divergent themes.

Results

Damages to infrastructure, including healthcare facilities and roadways, complicated the provision of timely health care for NCDs, patient transport, and pharmaceutical/medical supply chain continuity. Lengthy power outages at both healthcare facilities and private residences were barriers to healthcare service delivery, use of medical equipment, and storage of prescription medications with refrigeration, and led to a widespread mental health crisis. Cascading failures such as fuel shortages further compounded these challenges. The consequences of these impacts included the reported exacerbation of health conditions and loss of life among NCD patients.

Conclusions

Study findings identify contributors to morbidity and mortality among individuals with NCDs following Hurricane Maria. With the growing frequency of catastrophic disasters from natural hazards, the experiences of communities that endured these impacts offer important lessons regarding policies and practices to better support community disaster resilience and address the evolving preparedness needs of NCD patients.

Health System Disruption at the Primary Health Center Level Affected by Earthquake, Tsunami, and Liquefaction in 3 Districts of Central Sulawesi, Indonesia

OBJECTIVES

An earthquake followed by tsunami and liquefaction on September 28, 2018, in Central Sulawesi caused health system disruptions. This study aimed to know health system disruption at the primary health center (PHC) level due to the disaster in 3 districts (Palu, Sigi, Donggala) of Central Sulawesi.

METHODS

This was a qualitative study conducted in March 2019 involving 36 PHCs. Data were collected through interview of PHC officers using a structured questionnaire. Variables included disruption of management, budget, human resources, drug supply, Early Warning Alert and Response System (EWARS) of epidemic prone disease (EPD), human resource migration, health facility damage, and health facility access. Descriptive analysis was conducted to define disruption for a 1-y projection.

RESULTS

Health system disruptions in Palu affected management, budget, human resources, EWARS, health facility damage, and health access; occurred within 1-2 mo; and were projected to become better after 6 mo. Problems in Sigi were management, human resources, drug supply, EPD, and EWARS for 1 mo after disaster and were projected to be better after 2 mo. The problems in Donggala were health services access, management, human resources for 1 mo after the disaster and were projected to be normal after 2 mo.

CONCLUSIONS

Health system disruptions occurred in Central Sulawesi Province at the PHC level within 1-2 mo and were projected to become better after 3 mo in most PHCs.

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.

Protective effects of ischemic postconditioning on skeletal muscle following crush syndrome in the rat

Purpose

To investigate the effect of ischemic postconditioning (IPostC) on skeletal muscle and its optimal protocol.

Methods

This article is about an animal study of rat model of crush syndrome. Sixty rats were randomized into nine different IPostC intervention groups and a control group. The anesthetized rats were subjected to unilateral hindlimb 3-kg compression with a compression device for 6 h, followed by nine different IPostC intervention protocols.

Results

Serum levels of creatine kinase (CK) at 3 h post-crush became 2.3-3.9 times among all 10 groups after crush. At 72 h post-crush, serum CK level was reduced to 0.28-0.53 time in all intervention groups. The creatinine (CREA) level in the control group was elevated to 3.11 times at 3 h post-crush and reduced to1.77 time at 72 h post-crush. The potassium (K+) level in the control group was elevated to 1.65 and 1.41 time at 3 and 72 h post-crush, respectively.

Conclusions

Our IPostC intervention protocols can effectively protect rats from crush-induced elevation of serum CK, CREA, and K+ levels. The timing of IPostC intervention should be as early as possible, to ensure the protective effect.

Aetiologies and factors associated with poor clinical outcomes in rhabdomyolysis: a retrospective cohort study in an Australian trauma centre

Rhabdomyolysis is a clinical syndrome with significant morbidity and mortality that occurs as a result of traumatic and non-traumatic aetiologies. Acute kidney injury, the need for dialysis, and death, can occur due to rhabdomyolysis. This study explores the aetiologies, clinical outcomes and associated factors for poor outcomes in a cohort of patients with rhabdomyolysis in a tertiary trauma centre in Australia.

Kidney problems in disaster situations

Mass disasters, particularly earthquakes, cause many medical problems, including kidney problems, but an organized approach to cope with them was initiated only at the end of previous century, subsequent to the Armenian Spitak earthquake in 1988. Originally, interventions were focused on acute kidney injury (AKI) following crush injury and rhabdomyolysis in victims who had been trapped under the debris of collapsed buildings. However, similar problems were also registered in the context of other catastrophic events, especially man-made disasters like wars and torture. Other kidney-related problems, such as the preservation of treatment continuity in chronic kidney disease (CKD), especially in maintenance dialysis patients, deserved attention as well. Specific therapeutic principles apply to disaster-related kidney problems and these may differ from usual day-to-day clinical practice. Those approaches have been formulated in global and specific country-related guidelines and recommendations. It is clear that a well-conceived and organized management of kidney diseases in disasters benefits outcomes. Furthermore, it may be useful if the model and philosophy that were applied over the last three decades could be adapted by broadening the scope of disasters leading to intervention. Actions should be guided and coordinated by a panel of experts steering ad hoc interventions, rather than applying the "old" static model where a single coordinating center instructs and uses volunteers listed long before a potential event occurs.

APD or CAPD: one glove does not fit all

The use of Automated Peritoneal Dialysis (APD) in its various forms has increased over the past few years mainly in developed countries. This could be attributed to improved cycler design, apparent lifestyle benefits and the ability to achieve adequacy and ultrafiltration targets. However, the dilemma of choosing the superior modality between APD and Continuous Ambulatory Peritoneal Dialysis (CAPD) has not yet been resolved. When it comes to fast transporters and assisted PD, APD is certainly considered the most suitable Peritoneal Dialysis (PD) modality. Improved patients’ compliance, lower intraperitoneal pressure and possibly lower incidence of peritonitis have been also associated with APD. However, concerns regarding increased cost, a more rapid decline in residual renal function, inadequate sodium removal and disturbed sleep are APD’s setbacks. Besides APD superiority over CAPD in fast transporters, the other medical advantages of APD still remain controversial. In any case, APD should be readily available for all patients starting PD and the most important indication for its implementation remains patient’s choice.

Disasters, children and the kidneys

Following disasters, children are physically, psychologically and socially more vulnerable than adults; consequently, their morbidity and mortality are higher. The risks are especially high for orphans and unaccompanied children who are separated from their families, making them frequently victims of human trafficking, slavery, drug addiction, crime or sexual exploitation. Education of children and families about disaster-related risks and providing special protection in disaster preparedness plans may mitigate these threats. Kidney disease patients, both paediatric and adult, are extra vulnerable during disasters, because their treatment is dependent on technology and functioning infrastructure. Acute kidney injury, chronic kidney disease patients not on dialysis and dialysis and transplant patients are faced with extensive problems. Overall, similar treatment principles apply both for adults and paediatric kidney patients, but management of children is more problematic, because of substantial medical and logistic difficulties. To minimize drawbacks, it is vital to be prepared for renal disasters. Preparedness plans should address not only medical professionals, but also patients and their families. If problems cannot be coped with locally, calling for national and/or international help is mandatory. This paper describes the spectrum of disaster-related problems in children and the specific features in treating acute and chronic kidney disease in disasters.

T Cells and Acute Kidney Injury: A Two-Way Relationship

Acute Kidney Injury (AKI) complicates up to 10% of hospital admissions substantially increasing patient morbidity and mortality. Experimental evidence supports that AKI initiation and maintenance results from immune-mediated damage. Exogenous injury sources directly damage renal cells which produce pro-inflammatory mediators recruiting immune cells and furthering kidney injury. Many AKI studies focus on activation of innate immunity; major components include complement pathways, neutrophils, and monocytes. Recently, growing evidence emphasizes T lymphocytes role in affecting AKI pathogenesis and magnitude. In particular, T helper 17 lymphocytes enhance tissue injury by recruiting neutrophils and other inflammatory cells, while regulatory T cells conversely reduce renal injury and facilitate repair. Intriguingly, evidence supports local parenchymal-T cell interactions as essential to producing T cell phenotypic changes affecting long-term kidney and patient survival. Herein, we review T cells effects on AKI and patient outcomes and discuss related new therapeutic approaches to improve outcomes of affected individuals.

Acute Kidney Injury in Active Wars and Other Man-Made Disasters

Acute kidney injury (AKI) is frequent during wars and other man-made disasters, and contributes significantly to the overall death toll. War-related AKI may develop as a result of polytrauma, traumatic bleeding and hypovolemia, chemical and airborne toxin exposure, and crush syndrome. Thus, prerenal, intrinsic renal, or postrenal AKI may develop at the battlefield, in field hospitals, or tertiary care centers, resulting not only from traumatic, but also nontraumatic, etiologies. The prognosis usually is unfavorable because of systemic and polytrauma-related complications and suboptimal therapeutic interventions. Measures for decreasing the risk of AKI include making preparations for foreseeable disasters, and early management of polytrauma-related complications, hypovolemia, and other pathogenetic mechanisms. Transporting casualties initially to field hospitals, and afterward to higher-level health care facilities at the earliest convenience, is critical. Other man-made disasters also may cause AKI; however, the number of patients is mostly lower and treatment possibilities are broader than in war. If there is no alternative other than prolonged field care, the medical community must be prepared to offer health care and even perform dialysis in austere conditions, which in that case, is the only option to decrease the death toll resulting from AKI.

From quail to earthquakes and human conflict: a historical perspective of rhabdomyolysis

Rhabdomyolysis is a common cause of acute kidney injury, featuring muscle pain, weakness and dark urine and concurrent laboratory evidence of elevated muscle enzymes and myoglobinuria. Rhabdomyolysis is often seen in elderly and frail patients following prolonged immobilization, for example after a fall, but a variety of other causes are also well-described. What is unknown to most physicians dealing with such patients is the fascinating history of rhabdomyolysis. Cases of probable rhabdomyolysis have been reported since biblical times and during antiquity, often in the context of poisoning. Equally interesting is the link between rhabdomyolysis and armed conflict during the 20th century. Salient discoveries regarding the pathophysiology, diagnosis and treatment were made during the two world wars and in their aftermath. 'Haff disease', a form of rhabdomyolysis first described in 1920, has fascinated scientists and physicians alike, but the marine toxin causing it remains enigmatic even today. As a specialty, we have also learned a lot about the disease from 20th-century earthquakes, and networks of international help and cooperation have emerged. Finally, rhabdomyolysis has been described as a sequel to torture and similar forms of violence. Clinicians should be aware that rhabdomyolysis and the development of renal medicine are deeply intertwined with human history.

Carbon Monoxide Rescues the Developmental Lethality of Experimental Rat Models of Rhabdomyolysis-Induced Acute Kidney Injury

Many victims, after being extricated from a collapsed building as the result of a disaster, suffer from disaster nephrology, a term that is referred to as the crush syndrome (CS). Recommended treatments, which include dialysis or the continuous administration of massive amounts of fluid are not usually easy in cases of such mass natural disasters. In the present study, we examined the therapeutic performance of a biomimetic carbon monoxide (CO) delivery system, CO-enriched red blood cells (CO-RBCs), on experimental animal models of an acute kidney injury (AKI) induced by traumatic and nontraumatic rhabdomyolysis, including CS and rhabdomyolysis with massive hemorrhage shock. A single CO-RBC treatment was found to effectively suppress the pathogenesis of AKI with the mortality in these model rats being improved. In addition, in further studies using glycerol-induced rhabdomyolysis model rats, the pathogenesis of which is similar to that for the CS, AKI and mortality were also reduced as the result of a CO-RBC treatment. Furthermore, CO-RBCs were found to have renoprotective effects via the suppression of subsequent heme protein-associated renal oxidative injury; the oxidation of myoglobin in the kidneys, the generation of reactive oxygen species by free heme produced from degraded-cytochrome P450 and hemoglobin-associated renal injury. Because CO-RBCs can be prepared and used at both hospitals and at a disaster site, these findings suggest that CO-RBCs have the potential for use as a novel cell therapy against both nontraumatic and traumatic rhabdomyolysis including CS-induced AKI. SIGNIFICANCE STATEMENT: After mass natural and man-made disasters, people who are trapped in collapsed buildings are in danger of acute kidney injury (AKI), including crush syndrome (CS)-related AKI. This paper reports that carbon monoxide-enriched red blood cells (CO-RBCs), which can be prepared at both hospitals and disaster sites, dramatically suppressed the pathogenesis of CS-related AKI, thus improving mortality via suppressing heme protein-associated renal injuries. CO-RBCs have the potential for serving as a practical therapeutic agent against disaster nephrology associated with the CS.

Anisodamine Ameliorates Hyperkalemia during Crush Syndrome through Estradiol-Induced Enhancement of Insulin Sensitivity

Hyperkalemia is a major cause of on-site death in crush syndrome (CS), which is more severe and common in male victims. Anisodamine is a belladonna alkaloid and widely used in China for treatment of shock through activation of α7 nicotinic acetylcholine receptor (α7nAChR). The present work was designed to study the protective effect of anisodamine in CS and the possible role of estradiol involved. Male and ovariectomized female CS mice exhibited lower serum estradiol and insulin sensitivity, and higher potassium compared to the relative female controls at 6 h after decompression. There was no gender difference in on-site mortality in CS mice within 24 h after decompression. Serum estradiol increased with similar values in CS mice of both gender compared to that in normal mice. Anisodamine decreased serum potassium and increased serum estradiol and insulin sensitivity in CS mice, and methyllycaconitine, selective antagonist of α7nAChR, counteracted such effects of anisodamine. Treatment with anisodamine or estradiol increased serum estradiol and insulin sensitivity, decreased serum potassium and on-site mortality, and eliminated the difference in these parameters between CS mice received ovariectomy or its sham operation. Anisodamine could also increase blood pressure in CS rats within 3.5 h after decompression, which could also be attenuated by methyllycaconitine, without influences on heart rate. These results suggest that activation of α7nAChR with anisodamine could decrease serum potassium and on-site mortality in CS through estradiol-induced enhancement of insulin sensitivity.

A Novel Perfusion System for Damage Control of Hyperkalemia in Swine

INTRODUCTION

The standard of care for refractory hyperkalemia is renal replacement therapy (RRT). However, traditional RRT requires specialized equipment, trained personnel, and large amounts of dialysate. It is therefore poorly suited for austere environments. We hypothesized that a simplified hemoperfusion system could control serum potassium concentration in a swine model of acute hyperkalemia.

METHODS

Ten pigs were anesthetized and instrumented. A dialysis catheter was inserted. After bilateral nephrectomy, animals received intravenous potassium chloride and were randomized to the control or treatment group. In both groups, blood was pumped through an extracorporeal circuit (EC) with an in-line hemodialyzer. In the treatment arm, ultrafiltrate from the hemodialyzer was diverted through cartridges containing novel potassium binding beads and returned to the EC. Blood samples were obtained every 30 min for 6 h.

RESULTS

Serum potassium concentration was significantly lower in the treatment than in the control group over time (P = 0.02). There was no difference in serum total calcium concentration for group or time (P = 0.13 and 0.44, respectively) or platelet count between groups or over time (P = 0.28 and 1, respectively). No significant EC thrombosis occurred. Two of five animals in the control group and none in the treatment group developed arrhythmias. All animals survived until end of experiment.

CONCLUSIONS

A simplified hemoperfusion system removed potassium in a porcine model. In austere settings, this system could be used to temporize patients with hyperkalemia until evacuation to a facility with traditional RRT.

Renal Failure Patients in Disasters

Disasters occur regularly, and frequently large numbers of patients treated with maintenance dialysis or with the recent onset of acute kidney injury are put at risk owing to the lack of access to dialysis care precipitating also a kidney failure disaster. The absence of necessary dialysis treatments can result in excessive emergency department visits, hospitalizations, morbidity, or an early death. Those with kidney failure are often evaluated in disaster medical locations or hospitals without nephrologists in attendance. Here we offer guidance for medical personnel evaluating such patients so that dialysis-dependent individuals can be properly assessed and managed with the need for urgent dialysis recognized. A disaster dialysis triage system is proposed. (Disaster Med Public Health Preparedness. 2019;13:782-790).

Comparison of the effects of volemic reposition with 7.5% NaCl or blood in an experimental model of muscular compression and hemorrhagic shock

Objective

Crush syndrome is characterized by traumatic muscular injuries with severe systemic clinical repercussions. The systemic inflammatory reaction characterized acutely by infiltration of neutrophils in the lungs has been studied as part of the spectrum of crush syndrome. Experimental research may demonstrate alternative treatments for crush syndrome. The authors studied the hypothesis that hypertonic saline solution (7.5% NaCl) could minimize the local and systemic effects in a model of muscular compression and hemorrhagic shock.

Methods

Rabbits were submitted to a new model of muscle compression associated with hemorrhagic shock. Compression was applied through an Esmarch bandage, used for 1 h on the entire right lower limb. Hemorrhagic shock was induced for 1 h by dissection and catheterization of the carotid artery. Blood replacement or hypertonic saline solution was used to treat the shock. Biochemical analysis of plasma, quantification of muscular edema, and infiltration of inflammatory cells in the lungs were carried out.

Results

Animals treated with hypertonic solution presented the same hemodynamic response as the blood treated patients, less water in the compressed muscles and less infiltration of inflammatory cells in the lungs. The blood group presented hypocalcemia, a facet of crush syndrome.

Conclusions

The proposed model was effective for the study of crush syndrome associated with hemorrhagic shock. The treatment with hypertonic solution showed benefits when compared with blood volume replacement.

Peritoneal Dialysis in Austere Environments: An Emergent Approach to Renal Failure Management

Peritoneal dialysis (PD) is a means of renal replacement therapy (RRT) that can be performed in remote settings with limited resources, including regions that lack electrical power. PD is a mainstay of end-stage renal disease (ESRD) therapy worldwide, and the ease of initiation and maintenance has enabled it to flourish in both resource-limited and resource-abundant settings. In natural disaster scenarios, military conflicts, and other austere areas, PD may be the only available life-saving measure for acute kidney injury (AKI) or ESRD. PD in austere environments is not without challenges, including catheter placement, availability of dialysate, and medical complications related to the procedure itself. However, when hemodialysis is unavailable, PD can be performed using generally available medical supplies including sterile tubing and intravenous fluids. Amidst the ever-increasing global burden of ESRD and AKI, the ability to perform PD is essential for many medical facilities.

Non-machinery dialysis that achieves blood purification therapy without using full-scale dialysis machines

An electrical or water supply and a blood purification machine are required for renal replacement therapy. There is a possibility that acute kidney injury can occur in large numbers and on a wide scale in the case of a massive earthquake, and there is the potential risk that the current supply will be unable to cope with acute kidney injury cases. However, non-machinery dialysis requires exclusive circuits and has the characteristic of not requiring the full-scale dialysis machines. We performed perfusion experiments that used non-machinery dialysis and recent blood purification machines in 30-min intervals, and the effectiveness of non-machinery dialysis was evaluated by the assessing the removal efficiency of potassium, which causes lethal arrhythmia during acute kidney injury. The non-machinery dialysis potassium removal rate was at the same level as continuous blood purification machines with a dialysate flow rate of 5 L/h after 15 min and continuous blood purification machines with a dialysate flow rate of 3 L/h after 30 min. Non-machinery dialysis required an exclusive dialysate circuit, the frequent need to replace bags, and new dialysate exchanged once every 30 min. However, it can be seen as an effective renal replacement therapy for crush-related acute kidney injury patients, even in locations or facilities not having the full-scale dialysis machines.

How Should Disaster Base Hospitals Prepare for Dialysis Therapy after Earthquakes? Introduction of Double Water Piping Circuits Provided by Well Water System

After earthquakes, continuing dialysis for patients with ESRD and patients suffering from crush syndrome is the serious problem. In this paper, we analyzed the failure of the provision of dialysis services observed in recent disasters and discussed how to prepare for disasters to continue dialysis therapy. Japan has frequently experienced devastating earthquakes. A lot of dialysis centers could not continue dialysis treatment owing to damage caused by these earthquakes. The survey by Japanese Society for Dialysis Treatment (JSDT) after the Great East Japan Earthquake in 2011 showed that failure of lifelines such as electric power and water supply was the leading cause of the malfunction of dialysis treatment. Our hospital is located in Shizuoka Prefecture, where one of the biggest earthquakes is predicted to occur in the near future. In addition to reconstructing earthquake-resistant buildings and facilities, we therefore have adopted double electric and water lifelines by introducing emergency generators and well water supply systems. It is very important to inform politicians, bureaucrats, and local water departments that dialysis treatment, a life sustaining therapy for patients with end stage renal diseases, requires a large amount of water. We cannot prevent an earthquake but can curb the extent of a disaster by preparing for earthquakes.

Nephrology: As It Was Then, But Is Not Now

Diseases of the kidney are old, but the discipline dedicated to their study, nephrology, is barely more than 50 years old. As recounted in this recollection of those events, the rudiments of what would become nephrology emerged in the time between the 2 World Wars from basic studies of normal kidney function and flourished after the integration of their methodologies into clinical medicine thereafter. Although shaped by studies of kidney function in the 1960s, it was the subsequent advent of dialysis that fueled the growth of nephrology well into the 21st century. Although to some extent this growth was a product of technical developments (micropuncture, dialysis, biopsy, etc), it was the paradigm shifts they engendered that brought about the revolutionary changes that stimulated the growth of nephrology from its formative years in the 1960s. Notable among those was the classification of chronic kidney disease on the basis of kidney function, calculated from serum creatinine level as estimated glomerular filtration rate, that has expanded nephrology's interaction with and integration into other disciplines and begat the recent outpouring of epidemiologic and interventional studies, thereby establishing it as a leading discipline dedicated to improving outcomes for individuals with kidney disease worldwide.

Beyond muscle destruction: a systematic review of rhabdomyolysis for clinical practice

Background

Rhabdomyolysis is a clinical syndrome that comprises destruction of skeletal muscle with outflow of intracellular muscle content into the bloodstream. There is a great heterogeneity in the literature regarding definition, epidemiology, and treatment. The aim of this systematic literature review was to summarize the current state of knowledge regarding the epidemiologic data, definition, and management of rhabdomyolysis.

Methods

A systematic search was conducted using the keywords “rhabdomyolysis” and “crush syndrome” covering all articles from January 2006 to December 2015 in three databases (MEDLINE, SCOPUS, and ScienceDirect). The search was divided into two steps: first, all articles that included data regarding definition, pathophysiology, and diagnosis were identified, excluding only case reports; then articles of original research with humans that reported epidemiological data (e.g., risk factors, common etiologies, and mortality) or treatment of rhabdomyolysis were identified. Information was summarized and organized based on these topics.

Results

The search generated 5632 articles. After screening titles and abstracts, 164 articles were retrieved and read: 56 articles met the final inclusion criteria; 23 were reviews (narrative or systematic); 16 were original articles containing epidemiological data; and six contained treatment specifications for patients with rhabdomyolysis.

Conclusion

Most studies defined rhabdomyolysis based on creatine kinase values five times above the upper limit of normal. Etiologies differ among the adult and pediatric populations and no randomized controlled trials have been done to compare intravenous fluid therapy alone versus intravenous fluid therapy with bicarbonate and/or mannitol.

Acute Kidney Injury in Asia

BACKGROUND

Acute kidney injury (AKI) is a common disorder and is associated with a high morbidity and mortality worldwide. The diversity of the climate and of the socioeconomic and developmental status in Asia has a great influence on the etiology and presentation of AKI in different regions. In view of the International Society of Nephrology's 0by25 initiative, more and more attention has been paid to AKI in Asian countries.

SUMMARY

In this review, we summarize the recent achievements with regard to the prevalence and clinical patterns of AKI in Asian countries. Epidemiological studies have revealed the huge medical and economic burden of AKI in Eastern Asian countries, whereas the true epidemiological picture of AKI in the tropical areas is still not well understood. In high-income Asian regions, the presentation of AKI resembles that in other developed countries in Europe and North America. In low-income regions and tropical areas, infections, environmental toxins, and obstetric complications remain the major culprits in most cases of AKI. Preventive opportunities are missed because of failure to recognize the risk factors and early signs of AKI. Patients often present late for treatment or are recognized late by physicians, which leads to more severe kidney injury, multiorgan involvement, and increased mortality. There is significant undertreatment of AKI in many regions, and medical resources for renal replacement therapy are not universally available.

KEY MESSAGES

More efforts should be made to increase public awareness, establish preventive approaches in communities, educate health-care practitioner entities to achieve better recognition, and form specialist renal teams to improve the treatment of AKI. The choice of renal replacement therapy should fit patients' needs, and peritoneal dialysis can be practiced more frequently in the treatment of AKI patients.

FACTS FROM EAST AND WEST

(1) More than 90% of the patients recruited in AKI studies using KDIGO-equivalent criteria originate from North America, Europe, or Oceania, although these regions represent less than a fifth of the global population. However, the pooled incidence of AKI in hospitalized patients reaches 20% globally with moderate variance between regions. (2) The lower incidence rates observed in Asian countries (except Japan) may be due to a poorer recognition rate, for instance because of less systematically performed serum creatinine tests. (3) AKI patients in South and Southeastern Asia are younger than in East Asia and Western countries and present with fewer comorbidities. (4) Asian countries (and to a certain extent Latin America) face specific challenges that lead to AKI: nephrotoxicity of traditional herbal and less strictly regulated nonprescription medicines, environmental toxins (snake, bee, and wasp venoms), and tropical infectious diseases (malaria and leptospirosis). A higher incidence and less efficient management of natural disasters (particularly earthquakes) are also causes of AKI that Western countries are less likely to encounter. (5) The incidence of obstetric AKI decreased globally together with an improvement in socioeconomic levels particularly in China and India in the last decades. However, antenatal care and abortion management must be improved to reduce AKI in women, particularly in rural areas. (6) Earlier nephrology referral and better access to peritoneal dialysis should improve the outcome of AKI patients.

Activation of α7 Nicotinic Acetylcholine Receptor Decreases On-site Mortality in Crush Syndrome through Insulin Signaling-Na/K-ATPase Pathway

On-site mortality in crush syndrome remains high due to lack of effective drugs based on definite diagnosis. Anisodamine (Ani) is widely used in China for treatment of shock, and activation of α7 nicotinic acetylcholine receptor (α7nAChR) mediates such antishock effect. The present work was designed to test whether activation of α7nAChR with Ani decreased mortality in crush syndrome shortly after decompression. Sprague-Dawley rats and C57BL/6 mice with crush syndrome were injected with Ani (20 mg/kg and 28 mg/kg respectively, i.p.) 30 min before decompression. Survival time, serum potassium, insulin, and glucose levels were observed shortly after decompression. Involvement of α7nAChR was verified with methyllycaconitine (selective α7nAChR antagonist) and PNU282987 (selective α7nAChR agonist), or in α7nAChR knockout mice. Effect of Ani was also appraised in C2C12 myotubes. Ani reduced mortality and serum potassium and enhanced insulin sensitivity shortly after decompression in animals with crush syndrome, and PNU282987 exerted similar effects. Such effects were counteracted by methyllycaconitine or in α7nAChR knockout mice. Mortality and serum potassium in rats with hyperkalemia were also reduced by Ani. Phosphorylation of Na/K-ATPase was enhanced by Ani in C2C12 myotubes. Inhibition of tyrosine kinase on insulin receptor, phosphoinositide 3-kinase, mammalian target of rapamycin, signal transducer and activator of transcription 3, and Na/K-ATPase counteracted the effect of Ani on extracellular potassium. These findings demonstrated that activation of α7nAChR could decrease on-site mortality in crush syndrome, at least in part based on the decline of serum potassium through insulin signaling-Na/K-ATPase pathway.