Symmetrical peripheral gangrene in critical illness

Limb Ischemic Necrosis Secondary to Microvascular Thrombosis: A Brief Historical Review

Ischemic limb injury can be broadly classified into arterial (absent pulses) and venous/microvascular (detectable pulses); the latter can be divided into two overlapping disorders-venous limb gangrene (VLG) and symmetrical peripheral gangrene (SPG). Both VLG and SPG feature predominant acral (distal) extremity ischemic necrosis, although in some instances, concomitant nonacral ischemia/skin necrosis occurs. Historically, for coagulopathic disorders with prominent nonacral ischemic necrosis, clinician-scientists implicated depletion of natural anticoagulants, especially involving the protein C (PC) system. This historical review traces the recognition of natural anticoagulant depletion as a key feature of nonacral ischemic syndromes, such as classic warfarin-induced skin necrosis, neonatal purpura fulminans (PF), and meningococcemia-associated PF. However, only after several decades was it recognized that natural anticoagulant depletion is also a key feature of predominantly acral ischemic microthrombosis syndromes-VLG and SPG-even when accompanying nonacral thrombosis is not present. These acquired acral limb ischemic syndromes typically involve the triad of (a) disseminated intravascular coagulation, (b) natural anticoagulant depletion, and (c) a localizing explanation for microthrombosis occurring in one or more limbs, either deep vein thrombosis (helping to explain VLG) or circulatory shock (helping to explain SPG). In most cases of VLG or SPG there are one or more events that exacerbate natural anticoagulant depletion, such as warfarin therapy (e.g., warfarin-associated VLG complicating heparin-induced thrombocytopenia or cancer hypercoagulability) or acute ischemic hepatitis ("shock liver") as a proximate factor predisposing to severe depletion of hepatically synthesized natural anticoagulants (PC, antithrombin) in the setting of circulatory shock.

Limb Necrosis in the Setting of Vasopressor Use

BACKGROUND

It remains poorly understood why only some hemodynamically unstable patients who receive aggressive treatment with vasopressor medications develop limb necrosis.

OBJECTIVE

To determine the incidence of limb necrosis and the factors associated with it following high-dose vasopressor therapy.

METHODS

A retrospective case-control medical records review was performed of patients aged 18 to 89 years who received vasopressor therapy between 2012 and 2021 in a single academic medical center. The study population was stratified by the development of limb necrosis following vasopressor use. Patients who experienced necrosis were compared with age- and sex-matched controls who did not experience necrosis. Demographic information, comorbidities, and medication details were recorded.

RESULTS

The incidence of limb necrosis following vasopressor administration was 0.25%. Neither baseline demographics nor medical comorbidities differed significantly between groups. Necrosis was present in the same limb as the arterial catheter most often for femoral catheters. The vasopressor dose administered was significantly higher in the necrosis group than in the control group for ephedrine (P = .02) but not for the other agents. The duration of therapy was significantly longer in the necrosis group than in the control group for norepinephrine (P = .001), epinephrine (P = .04), and ephedrine (P = .01). The duration of vasopressin administration did not differ significantly between groups.

CONCLUSION

The findings of this study suggest that medication-specific factors, rather than patient and disease characteristics, should guide clinical management of necrosis in the setting of vasopressor administration.

A career in solving clinical-pathological conundrums: Heyde syndrome, anti-platelet factor 4 disorders, and microvascular limb ischemic necrosis

Hematology is a clinical specialty with strong roots in the laboratory; accordingly, the lab can help solve perplexing clinical problems. This review highlights clinical-pathological conundrums addressed during my 35-year hematology career at McMaster University. Heyde syndrome is the association between aortic stenosis and bleeding gastrointestinal (GI) angiodysplasia where the bleeding is usually cured by aortic valve replacement; the chance reading of a neonatal study showing reversible deficiency of high-molecular-weight (HMW) multimers of von Willebrand factor (vWF) following surgical correction of congenital heart disease provided the key insight that a subtle deficiency of HMW multimers of vWF explains Heyde syndrome. The unusual immunobiology of heparin-induced thrombocytopenia (HIT)-a highly prothrombotic, antibody-mediated, anti-platelet factor 4 (PF4) disorder featuring rapid appearance and then disappearance (seroreversion) of the pathological heparin-dependent platelet-activating antibodies-permitted identification of key clinical features that informed development of a scoring system (4Ts) to aid in HIT diagnosis. Atypical clinical presentations of HIT prompted identification of heparin-independent anti-PF4 antibodies, now recognized as the explanation for vaccine-induced immune thrombotic thrombocytopenia (VITT), as well as VITT-like disorders triggered by adenovirus infection. Another unusual feature of HIT is its strong association with limb ischemia, including limb necrosis secondary to deep-vein/microvascular thrombosis (venous limb gangrene). The remarkable observation that supratherapeutic warfarin anticoagulation predisposes to HIT- and cancer-associated venous limb gangrene provided insight into disturbed procoagulant/anticoagulant balance; these concepts are relevant to microvascular thrombosis in critical illness (symmetrical peripheral gangrene), including a pathophysiological role for proximate "shock liver" (impaired hepatic synthesis of natural anticoagulants).

Relationship Between Symmetrical Peripheral Gangrene Patients and Using Vasopressors in the Intensive Care Unit

Symmetrical peripheral gangrene (SPG) is a rare yet severe condition characterized by peripheral ischemic lesions without significant vascular occlusion. Its clinical presentation includes peripheral cyanosis, mottling, and symmetrical ischemia of distal limbs, often progressing to gangrene. Recent years have seen a rise in SPG cases, with mortality rates ranging from 40% to 90%. The condition is associated with systemic diseases, such as sepsis, vasculitis, and coagulopathy. DIC frequently complicates SPG, reflecting a disturbed procoagulant-anticoagulant balance and depletion of natural anticoagulants. While vasopressor therapy, particularly high-dose administration, has been implicated in SPG pathogenesis due to sustained vasoconstriction or idiosyncratic responses, recent evidence suggests it may not be the underlying cause. Studies indicate a low incidence of ischemic limb necrosis associated with high-dose vasopressors, with DIC and shock liver potentially explaining limb ischemia instead. The characteristic temporal interval between the onset of shock liver and limb ischemic necrosis suggests a more complex pathophysiology. The role of infectious agents, such as bacteria and viruses, in SPG pathogenesis is under investigation, with both direct vascular invasion and immune-mediated mechanisms proposed. Diagnosis involves ruling out other causes of acral gangrene through clinical examination, laboratory tests, imaging studies, and biopsy. Treatment strategies aim to halt disease progression, eliminate causative factors, and prevent complications. While anticoagulants, vasodilators, and adjunctive therapies like hyperbaric oxygen show promise, the efficacy of interventions varies, emphasizing the need for individualized management. Notably, hemoadsorption has emerged as a promising treatment, demonstrating significant improvement in SPG cases. Amputation remains a last resort option in irreversible cases. Early recognition and multidisciplinary management are crucial for improving outcomes. Further research is needed to better understand SPG's etiology and develop effective treatments through collaborative efforts.

Puerperal septic shock complicated with symmetrical peripheral gangrene: A case report

RATIONALE

Puerperal sepsis is a life-threatening condition caused by infection that can rapidly progress to multisystem infection and toxin-mediated shock. Symmetrical peripheral gangrene is defined as symmetrical distal ischemic damage in two or more sites in the absence of major vascular occlusive disease. The syndrome is devastating and rare. In this study, we introduce a case of puerperal septicemia complicated by symmetrical peripheral gangrene.

PATIENT CONCERNS

A 23-year-old woman delivered a live female infant vaginally after cervical balloon dilatation at 39 weeks of gestation. Persistent hyperthermia developed on the first postpartum day. After experiencing ventricular fibrillation, acute liver failure, and acute pulmonary edema, she developed blackened extremities on the 5th postpartum day.

DIAGNOSES

Puerperal septicemia complicated by symmetrical peripheral gangrene.

INTERVENTIONS

Upon transfer to our hospital, the patient was enrolled in the intensive care unit and underwent anti-infective and amputation surgery.

OUTCOMES

After the surgery, the patient recovered well and was successfully discharged from the hospital.

LESSONS

Early detection and timely treatment is the best way to reduce the mortality and sequelae of puerperal sepsis. Physicians should be alert to the possibility of comorbid symmetrical peripheral gangrene when sepsis patients present with hepatic impairment.

Consumptive coagulopathy in the ICU

A consumptive coagulopathy describes a situation where there is a loss of hemostatic factors, which leads to an increased risk of bleeding. Some recent studies have used the term interchangeably with disseminated intravascular coagulation (DIC), but we have reverted to the older definition, which covers a broader range of issues where there is loss of hemostatic factors due to multiple causes, which includes systemic activation of coagulation as seen in DIC. Therefore, the term consumptive coagulopathy covers conditions from the hemostatic effects of major hemorrhage to the use of extracorporeal circuits to true DIC. We review the current understanding of the pathophysiology, diagnosis, and management of common consumptive coagulopathy in critical care patients, focusing on recent advances and controversies. Particular emphasis is given to DIC because it is a common and often life-threatening condition in critical care patients and is characterized by the simultaneous occurrence of widespread microvascular thrombosis and bleeding. Second, we focus on the effect of modern medical technology, such as extracorporeal membrane oxygenation, on hemostasis.

Waterhouse-Friderichsen syndrome following a dog bite in an asplenic patient: case report and review of the literature

The Waterhouse-Friderichsen syndrome represents a critical condition characterized by a septic shock associated with a disseminated intravascular coagulation causing the plugging of the microvascular network virtually all organs and systems, including the skin, the kidneys, the liver, and adrenal glands; the mortality rate is elevated, and survivors often must undergo multiple limb amputations. Here, we describe the uncommon case of an asplenic patient who developed this syndrome after a superficial wound caused by a dog bite causing an initial infection due to Capnocytophaga canimorsus that is part of the normal oral microbiome of pets. The clinical and pathological findings and the current and future therapeutic options are reviewed and discussed.

Differentiation of Lower Extremity Skin Changes in the Intensive Care Setting

Digital and lower extremity skin changes often signify critical underlying disorders. Patients in the intensive care unit also frequently have hemodynamic instability requiring the use of vasoactive medications, which may lead to various presentations of limb ischemia; preexisting conditions increase these patients' risk for arterial embolization. Most arterial emboli are clots that originate in the heart and travel to distant vascular beds, where they cause arterial occlusion, ischemia, and, potentially, infarction; the 2 most common sequelae are stroke and lower limb ischemia. Emboli also arise from atherosclerotic plaques. Other conditions can also cause skin color changes in this vulnerable population. Prompt recognition and differentiation of lower extremity skin changes can result in improved patient outcomes. A thorough literature search was conducted to differentiate the primary causes of lower extremity and digital skin changes in the critically ill patient and outline diagnostic and management techniques.

COVID-19 associated symmetrical peripheral gangrene: A case series

BACKGROUND AND AIMS

The novel coronavirus disease (COVID-19) caused by SARS-CoV-2 has turned the world topsy-turvy since its onset in 2019. The thromboinflammatory complications of this disease are common in critically ill patients and associated with poor prognosis. Symmetrical peripheral gangrene (SPG) is characterized by symmetrical distal gangrene in absence of any large vessel occlusion or vasculitis and it is usually associated with critical illness. Our aim was to report the clinical profile and outcome of patients diagnosed with SPG associated with COVID-19. To the best of our knowledge, no such similar cases have been reported till date.

METHODS

In this case series, we have discussed the clinical presentation, laboratory parameters and outcome in a series of two patients of SPG associated with COVID-19 and also compared those findings. Due to paucity of data, we also reviewed the literature on this under-diagnosed and rarely reported condition and association.

RESULTS

Two consecutive patients (both males, age range: 37-42 years, mean: 39.5 years) were admitted with the diagnosis of COVID-19 associated SPG. Both patients had clinical and laboratory evidence of disseminated intravascular coagulation (DIC). Leucopenia was noted in both patients. Despite vigorous therapy, both patients succumbed to their illness within a fortnight of admission.

CONCLUSION

SPG in the background of COVID-19 portends a fatal outcome. Physicians should be aware of its grim prognosis.

Hirudotherapy for limb ischemia in the pediatric intensive care unit: A retrospective observational cohort

BACKGROUND

Acute limb ischemia due to microvascular malperfusion may be refractory to initial therapies. Medicinal leech therapy (hirudotherapy) has been attempted in plastic and reconstructive surgery to improve venous congestion in ischemic flaps; however, there are minimal reports related to ischemia secondary to arterial malperfusion. We evaluated a pediatric cohort from an academic intensive care unit with refractory limb ischemia in whom hirudotherapy was attempted to elucidate its use and outcomes.

METHOD

Institutional patient database was queried to identify pediatric patients (<18 years) who received hirudotherapy in the pediatric critical care unit and met inclusion/exclusion criteria. Patient charts were evaluated for indices including demographics, primary disease, coagulative status, vascular access, vasoactive medication dosing, bleeding, leech use, limb and mortality outcomes. Data was evaluated to identify trends or suspected impact on outcomes.

RESULTS

Hirudotherapy was used in 7 patients for limb ischemia, 5 with congenital heart disease, and 2 others with viremic shock. Time to leech application following recognition of ischemia averaged 3 days, with duration of use averaging 3.9 days. Five patients discontinued therapy due to bleeding. Mortality rate was 57%, all secondary to multiorgan failure. In 3 surviving patients, 4 of 5 treated limbs resulted in at minimum partial amputation. Vasoactive-inotropic score tended higher prior to leech application, suggesting a vasoconstrictive pathway for arterial malperfusion. No identifiable trends appeared associated with salvaged limb or adverse effects. Blood loss predictably increased with leech application, as did total transfusion requirement.

CONCLUSION

This case series establishes baseline data for use of hirudotherapy in critically ill children with acute limb ischemia caused by arterial malperfusion. Based on this retrospective cohort, we cannot recommend routine use of hirudotherapy for acute limb ischemia from arterial malperfusion in the pediatric intensive care unit. Application of leeches should be aligned with a protocol defining start and stop parameters, standardized leech utilization, and monitoring for adverse outcomes. Future study would benefit from consensus definitions of study outcomes, including perfusion recovery, tissue/limb salvage and bleeding manifestations. Additional prospective studies are needed prior to any standard or systematic recommendations for use.

Therapeutic strategies in patients with coagulopathy and disseminated intravascular coagulation: awareness of the phase-dependent characteristics

INTRODUCTION

Disseminated intravascular coagulation (DIC) has long been understood as a condition where both thrombotic and hemostatic abnormalities coexist. DIC is a difficult complication for clinicians to manage as it is due to multiple underlying complications of pathophysiologic abnormalities in diverse disease states. Ongoing research continues to define the meaning of DIC, evaluate therapeutic options, and how it presents with the complex paradigm of systemic activation of coagulation. In this review we introduce the current topis regarding this tough situation.

EVIDENCE ACQUISITION

Online search of published medical literature through MEDLINE and Web of Sience using the term "disseminated intravascular coagulation", "coagulopathy", "coagulation disorder", "hemostasis", "fibrinolysis", "thrombus" and "anticoagulants".

EVIDENCE SYNTHESIS

Articles were chosen for inclusion based on their relevance to disseminated intravascular coagulation, coagulopathy, hemostasis and thrombosis in sepsis, COVID-19, trauma, and obstetrics. Reference lists were reviewed to identify additional relevant articles.

CONCLUSIONS

DIC is recognized as a pathologically triggered and dysregulated systemic activation of coagulation in response to various noxious stimuli. DIC's phenotype and clinical manifestations can vary from prothrombotic to hemorrhagic, depending on the underlying diseases. However, the fundamental mechanisms of systemic and vascular endothelial dysfunction can be explained as different phases of the acute response, with an initial prothrombotic phase that can commonly change to hemostatic insufficiency. Thrombin is the key initiator of the pathophysiologic process along with endothelial injury and initially fibrinolysis activation followed by fibrinolysis suppression. There is no established approach for managing DIC beyond initially treating the underlying disease and replacement therapy for the management of coagulopathy. Targeting anticoagulation therapy with antithrombin concentrates and recombinant thrombomodulin for the prevention of microthrombus formation, and antifibrinolytic therapy using tranexamic acid for the coagulopathy after massive bleeding, continue to be studied as therapeutic options.