[Myorenal syndrome in forensic practice: molecular aspects of etiology and pathogenesis]

The objective of the study is to analyze the publications on biochemical aspects of myorenal syndrome (crush-syndrome) pathogenesis. Factors of trauma and other etiologies significant in terms of forensic practice that cause muscle tissue destruction are presented. Molecular processes in rhabdomyolysis and subsequent renal damage, the establishment of the sequence of which is important for forensic medicine, are outlined. The study results will improve our understanding of the of myorenal syndrome pathophysiology, its biochemical features, and optimize methods for its forensic diagnosis.

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.

Predicting factors of muscle necrosis in acute compartment syndrome of the lower extremity

BACKGROUND

Acute physiologic compartment syndrome (ACS) is a disorder of increased intra-compartmental pressure leading to decreased tissue perfusion and muscle necrosis. Tissue ischemia can result in irreversible muscle and nerve injury and requires urgent fasciotomy. The aim of this study was to determine the factors associated with the presence of necrotic muscle in patients undergoing leg fasciotomy.

METHODS

This is a retrospective cohort study of all patients undergoing fasciotomies for ACS of the leg at two level 1 trauma centers from 2000 to 2015. We found 1,028 patients who underwent leg fasciotomies. We excluded ACS at other sites than the leg, the index fasciotomy performed at an outside institution, prophylactic fasciotomy with no clinical signs of ACS, and patients with inadequate medical records. A total of 357 patients were included in the final analysis. We used bivariate analysis to assess which explanatory variables are associated with the main outcome measure, the presence of necrotic muscle at fasciotomy. We used multivariable regression analysis to determine association accounting for any confounding.

RESULTS

Of 357 cases of ACS of the leg, 14.6% of patients presented with an open fracture and 21.3% of patients were multiply injured. Overall, 14.3% of cases had muscle necrosis at the time of fasciotomy. Fifty-nine percent of patients with necrotic muscle required more than 3 debridements. Open fracture was the only statistically significant predictor of muscle necrosis (OR=2.8). Crush injury (OR=3.1) and soft tissue injuries (OR=2.8) were at an increased odds of necrotic muscle, but only marginally significant.

CONCLUSION

ACS is a potentially limb threatening condition often associated with poor outcomes, particularly when the diagnosis is delayed. Patients with open fracture have a three-fold increase in odds of necrotic muscle at the time of fasciotomy.

17β-estradiol alters mRNA co-expression after murine muscle injury and mild hypobaria

Here, we assessed the effects of 17β-estradiol exposure on mRNA co-expression patterns of muscle tissue during recovery in a closed muscle crush injury and hypobaria exposure murine model. Eighteen ovariectomized placebo-treated and 18 ovariectomized 17β-estradiol-treated female mice underwent closed muscle crush injury and hypobaric simulated flight. The mice recovered for 32, 96, or 192 h, and then were euthanized. Their harvested injured lateral gastrocnemius muscles underwent microarray analysis. We used weighted gene co-expression network analysis to construct a co-expression network for the control mice, and then applied the same network to the estrogen-treated mice. We compared the relationships between co-expression in gene modules over time between the two experimental groups. Enriched functional cluster analyses of significant co-expression network modules document a variety of different pathways of interest. Some of the functional cluster enrichments within several of the significantly correlated modules are related to the formation and function of microtubules. Our findings demonstrate that following a closed muscle crush injury in a murine model, the presence of 17β-estradiol alters mRNA co-expression patterns over time. It appears that estrogen promotes the expression of mRNA related to microtubule activity within the cytoskeleton of myofibers and in movement of organelles and receptors. Further study is needed, but the enrichment of these microtubule-related pathways may be integral in the muscle tissue regeneration process, and thus suggests that the presence of estrogen may promote muscle recovery through the work of the microtubules.

Impact statement

This study uses a murine model to address the clinical situation of transporting soldiers or civilians who have sustained skeletal muscle trauma by air. Our findings show that crush-injured muscle tissue of ovariectomized, 17β-estradiol-treated mice exposed to mild hypobaric hypoxia exhibited mRNA co-expression patterns among pathways associated with microtubule-dependent processes. Palmitoylation and other pathways necessary for movement of estrogen receptors to the cell membrane were also differentially enriched in the estrogen-treated mice. These first findings reframe the discussion regarding estrogen effects during muscle recovery from an inflammation-oriented inquiry to that of a structural, cytoskeletal inquiry and support additional research to understand the non-inflammation-related influences of estrogen during muscle recovery. Also, these results may suggest a role for estrogen or estrogen-like substances to treat muscle trauma.

Strategies for Intravenous Fluid Resuscitation in Trauma Patients

Intravenous fluid management of trauma patients is fraught with complex decisions that are often complicated by coagulopathy and blood loss. This review discusses the fluid management in trauma patients from the perspective of the developing world. In addition, the article describes an approach to specific circumstances in trauma fluid decision-making and provides recommendations for the resource-limited environment.

Wound management in disaster settings

BACKGROUND

Few guidelines exist for the initial management of wounds in disaster settings. As wounds sustained are often contaminated, there is a high risk of further complications from infection, both local and systemic. Healthcare workers with little to no surgical training often provide early wound care, and where resources and facilities are also often limited, and clear appropriate guidance is needed for early wound management.

METHODS

We undertook a systematic review focusing on the nature of wounds in disaster situations, and the outcomes of wound management in recent disasters. We then presented the findings to an international consensus panel with a view to formulating a guideline for the initial management of wounds by first responders and subsequent healthcare personnel as they deploy.

RESULTS

We included 62 studies in the review that described wound care challenges in a diverse range of disasters, and reported high rates of wound infection with multiple causative organisms. The panel defined a guideline in which the emphasis is on not closing wounds primarily but rather directing efforts toward cleaning, debridement, and dressing wounds in preparation for delayed primary closure, or further exploration and management by skilled surgeons.

CONCLUSION

Good wound care in disaster settings, as outlined in this article, can be achieved with relatively simple measures, and have important mortality and morbidity benefits.

Extreme Measures: Field Amputation on the Living and Dismemberment of the Deceased to Extricate Individuals Entrapped in Collapsed Structures

Collapsed structures, typically as a result of earthquakes, may result in individuals entrapped by their limbs under heavy structural elements. In addition, access to living persons may be blocked by the deceased. Individuals are often critically ill by the time they are found, and rapid extrication is warranted. This and other factors may necessitate field amputation of an extremity on a living person or dismemberment of the deceased to achieve a rescue. Although case reports have described industrial, mining, and transportation accidents, few discuss this potential in collapsed structures. Also, few specifically outline the indications or the decision process and associated administrative procedures that should be addressed before conducting these procedures. This report presents a review of the literature along with a limited case series. A discussion regarding relevant decision making is provided to encourage the development of protocols. An international consensus statement on these procedures is provided.

(Disaster Med Public Health Preparedness. 2012;6:428-435)

Amputations in natural disasters and mass casualties: staged approach

Amputation is a commonly performed procedure during natural disasters and mass casualties related to industrial accidents and military conflicts where large civilian populations are subjected to severe musculoskeletal trauma. Crush injuries and crush syndrome, an often-overwhelming number of casualties, delayed presentations, regional cultural and other factors, all can mandate a surgical approach to amputation that is different than that typically used under non-disaster conditions. The following article will review the subject of amputation during natural disasters and mass casualties with emphasis on a staged approach to minimise post-surgical complications, especially infection.

Medical complications associated with earthquakes

Major earthquakes are some of the most devastating natural disasters. The epidemiology of earthquake-related injuries and mortality is unique for these disasters. Because earthquakes frequently affect populous urban areas with poor structural standards, they often result in high death rates and mass casualties with many traumatic injuries. These injuries are highly mechanical and often multisystem, requiring intensive curative medical and surgical care at a time when the local and regional medical response capacities have been at least partly disrupted. Many patients surviving blunt and penetrating trauma and crush injuries have subsequent complications that lead to additional morbidity and mortality. Here, we review and summarise earthquake-induced injuries and medical complications affecting major organ systems.