Decompressive Hemicraniectomy After Cerebral Fat Embolism.

Fat embolism syndrome is a common occurrence after orthopedic trauma and surgery. Cerebral fat embolism (CFE) may arise after fat globules enter the arterial circulation. The neurological manifestations of CFE vary and generally carries a favorable outcome. A small number of reports exist regarding patients with CFE who experienced severe neurological deficits and significant edema on radiographic studies, and subsequently underwent decompressive hemicraniectomy (DHC), some of which had full neurological recoveries. Here, we present the case of a 21-year-old male who presented after a motorcycle accident with multiple orthopedic injuries, who after fixation did not awake from anesthesia. The patient was ultimately found to have cerebral fat emboli, and developed significant edema and swelling. The patient underwent DHC with subsequent cranioplasty and returned to his neurological baseline seven months after his initial injury. DHC for CFE has been described in a few cases with some patients have had substantive recoveries, including the present case. This case emphasizes the importance of promptly recognizing and reversing elevated intracranial pressures and the possibility of promising recoveries.

Cerebral fat embolism with turbid urine as the initial sign.

BACKGROUND: Cerebral fat embolism (CFE) is a rare but potentially fatal complication that can occur after long bone fractures. It represents one subcategory of fat embolisms (FE). Diagnosing CFE can be challenging due to its variable and nonspecific clinical manifestations. We report a case of CFE initially presenting with turbid urine, highlighting an often neglected sign. CASE PRESENTATION: A 69-year-old male was admitted after a traffic accident resulting in bilateral femoral fractures. Sixteen hours post-admission, grossly turbid urine was noted but received no special attention. Four hours later, he developed rapid deterioration of consciousness and respiratory distress. Neurological examination revealed increased upper limb muscle tone and absent voluntary movements of lower limbs. Brain MRI demonstrated a 'starfield pattern' of diffuse punctate lesions, pathognomonic for CFE. Urine microscopy confirmed abundant fat droplets. Supportive treatment and fracture fixation were performed. The patient regained consciousness after 3 months but had residual dysphasia and limb dyskinesia. CONCLUSION: CFE can present with isolated lipiduria preceding overt neurological or respiratory manifestations. Heightened awareness of this subtle sign in high-risk patients is crucial for early diagnosis and intervention. Prompt urine screening and neuroimaging should be considered when gross lipiduria occurs after long bone fractures.

A Fatal Case of Cerebral Fat Embolism: A Case Report.

Fat embolism syndrome (FES) is a rare but serious multisystem syndrome that occurs after 0.9% to 2.2% of fractures, with long bone and pelvic fractures being the most common. The classic triad of FES consists of neurological impairment, respiratory insufficiency, and petechial rash, which develops 12-72 hours after the initial incident. We hereby present a case of a patient who developed persistent altered consciousness, seizures, and hypoxia secondary to a comminuted sacral fracture. Although the patient could not survive owing to multiple factors, imaging played a pivotal role in expediting the diagnostic process and aiding early management.

Intramedullary nailing for floating knee injury complicated by pulmonary fat embolism: A case report and literature review.

A 28-year-old man involved in a serious motorcycle accident was admitted to our hospital with comminuted fractures of the ipsilateral femoral shaft and tibial shaft, as well as multiple fractures of the right lower limb, including the proximal fibula, medial malleolus, and the third and fourth distal metatarsals. In addition, the patient suffered a skin contusion and laceration of the right foot. On the first day of admission, this patient suddenly developed tachycardia, pyrexia, and tachypnoea, and was immediately transferred to the ICU for further treatment due to a CT-diagnosed pulmonary fat embolism (FE). As a symptomatic treatment, he received a prophylactic dose of low-molecular-weight heparin for 10 days, after which his condition improved. A Doppler ultrasound of the lower leg and a follow-up chest CT angiography were performed, which excluded any remaining thrombus and verified that the pulmonary FE had improved without deterioration. Closed-reduction and retrograde intramedullary nailing were performed for the femoral shaft fractures, while antegrade intramedullary nailing was performed for the tibial shaft fractures under general anaesthesia. In the three-year follow-up, the patient had recovered with good function of the right limb, without any respiratory discomfort. Both the femoral and tibial shaft fractures finally resolved without any further treatment. Ipsilateral femoral and tibial shaft fractures should undergo surgical stabilisation as early as possible to avoid pulmonary FEs. It is still controversial whether intramedullary nailing is suitable for floating knee injuries complicated by pulmonary FEs. However, if patients with pulmonary FEs require intramedullary nailing, we suggest that surgery should be performed after at least one week of anticoagulant use, when patient vital signs are stable and there is no sign of dyspnoea. In addition, patients should try to avoid reaming during the operation to prevent and decrease "second hit" for the lung.

Fat embolism and COVID-19 infection: autopsy and post-mortem laboratory findings in SARS-CoV-2 positive patients.

INTRODUCTION: The article is one of the very first autopsy reports worldwide, which associates COVID-19 infection and pulmonary fat embolism. AIMS: To point to a crucial connection between a severe acute respiratory syndrome caused by coronavirus 2 (SARS-CoV-2) infection and pulmonary fat embolism as one of the possible major mechanisms of severe COVID-19 symptoms. METHODS: Lung, brain and kidney tissues examination of 16 full human autopsy cases. All deceased suffered from COVID-19 infection, none of them was admitted to hospital prior to death, immediate causes of death vary. Autopsies accompanied by microbiological examination and histological examination using Oil Red O staining were performed. Consequently, we have implemented a control cohort consisting of 16 deceased with no presence of pulmonary infection and various immediate causes of death. RESULTS: Of the 16 autopsy cases, 11 (68.8%) were males and 5 (31.3%) females, with overall mean age 68.1 (39-86) years. Causes of death of studied subjects were natural, mostly from respiratory failure (in 12 cases, 75%). Cardiopulmonary resuscitation was performed in 7 cases (43.8%). None of dissected persons had larger signs of body trauma. Pulmonary fat embolism was found in 11 cases (68.8%), which generalised to kidneys in 8 patients (50% of all cases, 72.3% of cases with pulmonary fat embolism) and to brain tissue in 1 case. CONCLUSION: We demonstrated a reasonable relation between a COVID-19 disease and a variously severe fat embolism, severity of which does not directly correlate with body weight. Further investigation or even change of medical treatment needs to be considered in patients with COVID-19.

Intraoperative fat embolism syndrome associated with implantation of titanium sacroiliac joint fusion implants: a report of two cases.

Background: For patients undergoing long-construct fusion surgeries, simultaneous sacroiliac joint (SIJ) fusion is a growing trend in spine surgery. Some options for posterior SIJ fusion include 3D-printed triangular titanium implants or self-harvesting SIJ screws. Both implants require fixation within the sacrum and ileum. Fat embolism syndrome is a rare but known complication of lumbar pedicle instrumentation but has never been reported in association with SIJ fusion, regardless of implant type. We report the first two known cases of fat embolism associated with placement of SIJ fusion devices during long construct posterior spine fusion. Case Description: Case 1-a 50-year-old female with multiple previous spine surgeries complicated by osteomyelitis/diskitis that was successfully eradicated, underwent T10-pelvis posterior spinal fusion (PSF), L4 pedicle-subtracting-osteotomy, and bilateral SIJ fusion. During implantation of each SIJ fusion device, the patient's hemodynamic status deteriorated necessitating vasopressor support, intravenous fluid bolus, and hyperventilation, but quickly resolved. The case was completed without further issue, and she had an uneventful post-operative course. Case 2-a 71-year-old female with a past medical history of ankylosing spondylitis, previous L2-L5 PSF, rheumatoid arthritis on chronic steroids, underwent a T9-pelvis PSF, bilateral SIJ fusion, L4 pedicle subtraction osteotomy, T10-L1 Smith Peterson osteotomies. After implantation of the second SIJ fusion device, she became hypotensive and tachycardic, pulses were absent, and cardiopulmonary resuscitation was initiated. Pulses returned quickly, the index surgery was terminated, and she was transferred to the intensive care unit (ICU). In the ICU she was quickly weaned off the ventilator on post-operative day 1. On post-operative day 4, the patient returned to the operating room for completion of the surgery and had an extended, but uneventful, recovery afterwards. Conclusions: We report on the first two known cases of fat embolism syndrome occurring immediately after implantation of SIJ fusion devices. Spine surgeons should be aware of this rare, but potentially fatal, complication. Collaboration with the anesthesia team and optimization of the patient's hemodynamic status prior to implantation may help prevent catastrophic complications.

Epidemiology and risk factors for fat embolism in isolated lower extremity long bone fractures.

PURPOSE: Fat embolism syndrome (FES) is a serious complication after orthopedic trauma. The aim of this study was to identify risk factors for FES in isolated lower extremity long bone fractures. METHODS: The National Trauma Data Bank "NTDB" study included patients with isolated femoral and tibial fractures. A total of 344 patients with FES were propensity score matched with 981 patients without FES. Multivariate logistical regression was used to identify independent risk factors for FES. RESULTS: FES was diagnosed in 344 (0.03%) out of the 1,251,143 patients in the study populations. In the two matched groups, the mortality was 7% in the FES group and 1% in the No FES group (p < 0.001). FES was associated with an increased risk of ARDS, VTE, pneumonia, AKI, and stroke. Younger age, femur fractures, obesity, and diabetes mellitus were independent predictors of FES. Early operative fixation (≤ 48 h) was protective against FES. CONCLUSION: FES increases mortality by seven times. Young age, obesity, and diabetes mellitus are significant independent risk factors for FES. Early fixation is independently associated with a reduced risk of FES. LEVEL OF EVIDENCE: Level III. STUDY TYPE: Prognostic study.

A case of fatal fulminant fat embolism syndrome saved by VA-ECMO in the acute phase of multiple trauma.

Fat embolism syndrome (FES) is a rare complication of long bone fractures, with fulminant FES developing within 12 h of injury and often proving fatal (Shaikh, 2009 [1]). Here, we present a case of fulminant FES in a patient who developed sudden right heart failure after undergoing external fixation of a lower leg fracture and required veno-arterial extracorporeal membrane oxygenation (VA-ECMO). A 79-year-old woman injured in a traffic accident was transferred to our emergency department. Upon arrival, her level of consciousness deteriorated, and she developed circulatory failure. We promptly performed transcatheter arterial embolization for the pelvic fracture and external fixation of the tibiofibular fracture. Within four hours of the injury, she was admitted to our intensive care unit (ICU). Two hours after ICU admission, her hemodynamic status worsened, necessitating the administration of maximum catecholamine dose. Echocardiography revealed petechial hemorrhage of the palpebral conjunctiva and enlargement of the right ventricle. Despite maximal supportive care, the patient remained cardiovascularly unstable. Therefore, VA-ECMO was initiated to stabilize her hemodynamic status. Thereafter, her hemodynamics stabilized, and ECMO support was weaned off and removed on day 3. Subsequent magnetic resonance imaging revealed evidence of cerebral fat embolism. On day 9, she underwent open reduction of the left lower leg with internal fixation and was transferred to another hospital on day 29. This report documents the successful management of fulminant FES during the acute phase of multiple traumas. Clinicians should consider VA-ECMO when suspecting uncontrolled circulatory failure due to fulminant FES, even in the acute phase of multiple trauma.

Fat embolism syndrome: A severe case diagnosed early using dual-energy CT and saved with VA-ECMO and inhaled nitric oxide.

Diagnosing FES is difficult and time-consuming, and identify FES as an etiology of right ventricular volume overload for early diagnosis. Because FES is a reversible condition, even severe cases can bse treated if the patient survives the acute phase.

Pulmonary fat embolism in non-survivors after cardiopulmonary resuscitation.

BACKGROUND: Blunt trauma acting against the human body presents the fundamental cause of pulmonary fat embolism (PFE) and fat embolism syndrome. The aim of the present study was to investigate PFE in non-survivors after cardiopulmonary resuscitation (CPR). METHODS: This was a prospective cohort study conducted in University Hospital Ostrava, Czech Republic. Within a 4-year study period, all non-survivors after CPR because of out-of-hospital cardiac arrest were assessed for the study eligibility. The presence/seriousness of PFE was determined by microscopic examination of cryo-sections of lung tissue (staining with Oil Red O). RESULTS: In total, 106 persons after unsuccessful CPR were enrolled in the study. The most frequent cause of death in the study population (63.2% of cases) was cardiac disease (ischemic heart disease); PFE was not determined as the cause of death in any of our study cases. Sternal fractures were identified 66.9%, rib fractures (usually multiple) in 80.2% of study cases; the median number of rib fractures was 10.2 fractures per person. Serious intra-thoracic injuries were found in 34.9% of cases. Microscopic examination of lung cryo-sections revealed PFE in 40 (37.7%) study cases; PFE was most frequently evaluated as grade I or II. Occurrence of sternal and rib fractures was significantly higher in persons with PFE than between persons without PFE (p = 0.033 and p = <0.001). Number of rib fractures was also significantly higher in persons with PFE. The occurrence of serious intra-thoracic injuries was comparable in both our study groups (p = 0.089). CONCLUSIONS: PFE presents a common resuscitation injury which can be found in more than 30% of persons after CPR. Persons with resuscitation skeletal chest fractures have significantly higher risk of PFE development. During autopsy of persons after unsuccessful CPR, it is necessary to distinguish CPR-associated injuries including PFE from injuries that arise from other mechanisms.

[Clinical manifestation and imaging diagnostic analysis of fat embolism syndrome].

OBJECTIVE: To explore characteristics of clinical and imaging findings in patients with fat embolism syndrome. METHODS: From January 2021 to October 2022,clinical manifestations of 13 patients with fat embolism due to fracture or orthopaedic surgery were retrospectively analyzed,including 11 males and 2 females,aged from 17 to 60 years old. Mental and respiratory abnormalities and changes in vital signs occurred after admission or after surgery,and patient's chest and brain imaging results were abnormal. The patient's mental and respiratory abnormalities,vital signs,chest and brain imaging results were continuously monitored. RESULTS: The main clinical manifestations of fat embolism syndrome were abnormal pulmonary respiration in 13 patients,abnormal central nervous function in 7 patients,and spotted rash in 2 patients. Chest CT showed diffuse distribution of ground glass shadows in 13 patients,and severe symptoms were "snowstorm". Nine patients with ground glass fusion consolidation,5 patients with multiple nodules and 4 patients accompanied by bilateral pleural effusion. Head CT findings of 5 patients were negative,and head MRI findings of 1 patient showed multiple T1WI low signal,T2WI high signal shadow,DWI high signal shadow,and "starry sky sign" in basal ganglia,radiative crown,hemioval center,thalamus,frontal parietal cortex and subcortex. CONCLUSION: Fat embolism syndrome has a high mortality rate. Clinical manifestations of respiratory system and nervous system are not specific,and the skin spot rash has a characteristic manifestation. The "blizzard" sign is the specific manifestation of chest X-ray and CT examination of fat embolism,and the "starry sky" sign is the typical manifestation of diffusion-weighted sequence of brain MRI examination of fat embolism.

CT pulmonary arteriogram diagnosis of macroscopic fat embolism to the lung.

Pulmonary fat embolism (PFE) is a recognised complication of long bone fractures. The majority of cases represent microscopic embolism and are not detectable at CT pulmonary arteriography (CTPA). CT can be used to detect macroscopic fat based on Hounsfield attenuation. This case describes a case of macroscopic fat embolism to the pulmonary arteries which was confidently diagnosed at CTPA. Distinction from thromboembolism is important as treatment is supportive and may avoid risks of anticoagulation.

Bilateral Floating Knee Injuries Managed by Intramedullary Nailing - An Unusual Injury.

Introduction: Floating knee injuries were first described in 1975 by McBryde as concurrent femur and tibial fractures in an ipsilateral limb. They usually occurred in a polytrauma setting and presented with poor functional outcomes with frequent post-operative complications. Management of this injury was based on patient and fracture characteristics and can be done by external fixators, plating, and nailing. Case Report: A 24-year-old female presented with bilateral floating knees. She was operated on for a left femoral fracture with retrograde nailing when she developed tachycardia and underwent external fixation of the remaining fractures. She later developed a fat embolism which was managed accordingly for the same. After adequate stabilization, her right femur and tibia fractures were fixed by intramedullary nailing through a single percutaneous approach along with nailing for the left tibial fracture. She has satisfactory clinical outcomes on follow-up. Conclusion: Bilateral floating knee injuries are extremely rare injuries and should be managed on an emergency basis. Intraoperative and post-operative complications should be anticipated and managed accordingly. Good functional outcomes can be obtained by intramedullary nailing.

In vivo study to assess fat embolism resulting from the Reamer-Irrigator-Aspirator 2 system compared to a novel aspirator-based concept for intramedullary bone graft harvesting.

INTRODUCTION: Fat embolism (FE) following intramedullary (IM) reaming can cause severe pulmonary complications and sudden death. Recently, a new harvesting concept was introduced in which a novel aspirator is used first for bone marrow (BM) aspiration and then for subsequent aspiration of morselized endosteal bone during sequential reaming (A + R + A). In contrast to the established Reamer-Irrigator-Aspirator (RIA) 2 system, the new A + R + A concept allows for the evacuation of fatty BM prior to reaming. In this study, we hypothesized that the risk of FE, associated coagulopathic reactions and pulmonary FE would be comparable between the RIA 2 system and the A + R + A concept. MATERIALS AND METHODS: Intramedullary bone graft was harvested from intact femora of 16 Merino sheep (age: 1-2 years) with either the RIA 2 system (n = 8) or the A + R + A concept (n = 8). Fat intravasation was monitored with the Gurd test, coagulopathic response with D-dimer blood level concentration and pulmonary FE with histological evaluation of the lungs. RESULTS: The total number and average size of intravasated fat particles was similar between groups (p = 0.13 and p = 0.98, respectively). D-dimer concentration did not significantly increase within 4 h after completion of surgery (RIA 2: p = 0.82; A + R + A: p = 0.23), with an interaction effect similar between groups (p = 0.65). The average lung area covered with fat globules was similar between groups (p = 0.17). CONCLUSIONS: The use of the RIA 2 system and the novel A + R + A harvesting concept which consists of BM evacuation followed by sequential IM reaming and aspiration of endosteal bone, resulted in only minor fat intravasation, coagulopathic reactions and pulmonary FE, with no significant differences between the groups. Our results, therefore, suggest that both the RIA 2 system and the new A + R + A concept are comparable technologies in terms of FE-related complications.

Danger Zones of the Gluteal Anatomy: Improving the Safety Profile of the Gluteal Fat Grafting.

INTRODUCTION: Knowledge of the vascular anatomy is critical to performing safe gluteal surgery. To date, only the course of the main blood vessels within the muscles has been outlined. These findings are based on MRI and CTA images that do not conform to a topographically standardized and normalized probability distribution. OBJECTIVES: The aim of this study was to develop a three-dimensional mapping of the gluteal zones of high vascular density in relation to anatomical landmarks. MATERIALS AND METHODS: This single-center retrospective cohort analysis comprised all consecutive patients who underwent cone-beam computed tomography (CBCT) scans between January 2016 and October 2021. The location of blood vessels in the gluteal region was allometrically normalized in relation to anatomical landmarks. Moreover, the caliber and area of the blood vessels were assessed. RESULTS: CBCT scans of 32 patients with an average age of 64 ± 12 years (range 34-87 years) were included. Fifty-three percent were female. The median [IQR] caliber of the intramuscular gluteal vessels was 1.47 [1.15-1.88] mm, significantly greater than that of the subcutaneous vessels 1.09 [0.72-1.44] mm (p < 0.001). Vascular density was higher intramuscularly, as 4.5% of the area of the muscle was occupied by blood vessels, as opposed to 0.3% in the adipose tissue. CONCLUSION: The analysis of the CBCT scans showed a higher vascular density and larger vessels intramuscularly. We, therefore, recommend the injection of autologous fat merely to the subcutaneous plane. LEVEL OF EVIDENCE II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Reamer irrigator aspirator (RIA) reduces risk of fat embolism in bilateral pediatric femur shaft fractures: a case report.

A 14-year-old male patient was successfully treated with the reamer irrigator aspirator for femur intramedullary rod preparation after sustaining right and left closed femur fractures because of an all-terrain vehicle accident. In patients already categorized as high risk for fat embolism syndrome, such as those with bilateral femur fractures, reaming both femora greatly increases the likelihood of this complication. The reamer irrigator aspirator provides an effective tool that potentially mitigates the risk of fat embolism syndrome in pediatric patients with this type of orthopedic trauma.

Fat embolism syndrome associated with atraumatic compartment syndrome of the bilateral upper extremities: An unreported etiology.

Fat embolism syndrome (FES) is a potentially life-threatening condition that develops when fat embolism leads to clinical symptoms and multisystem dysfunction. The classic triad of respiratory distress, neurologic symptoms, and petechial rash are non-specific, and the lack of specific laboratory tests makes the diagnosis of FES difficult. Although FES is most common after long bone fractures, multiple conditions some of which are atraumatic have been associated with the development of FES. We report a case of FES that occurred in the setting of a non-traumatic compartment syndrome of the upper extremities. The pathologic and clinical findings, pathophysiology, diagnostic challenges, and pathologic methods to properly diagnose FES are discussed with a review of the relevant literature. This case highlights the importance of the autopsy in making a diagnosis of FES in cases where death could otherwise be incorrectly attributed to multi-organ system failure, shock, or sepsis.

Fat embolism syndrome in Duchenne muscular dystrophy: Report on a novel case and systematic literature review.

We report a non-ambulatory 13-year-old boy with Duchenne muscular dystrophy who experienced severe acute respiratory distress syndrome and cerebral fat embolism following elective soft tissue surgery. Post-surgery radiological examination revealed bilateral femoral fractures and marked osteopenia that were believed to have caused disseminated pulmonary and cerebral fat embolism. The patient had never been on glucocorticoid treatment. Five months post-surgery, he remained in a state of minimal consciousness. A literature review was performed and eleven publications included, providing case reports of a total number of 23 patients with Duchenne muscular dystrophy with fat embolism syndrome. The most common causes were falls from the wheelchair that predominantly resulted in femoral fractures. Median age at the event was around 14 years. Seven patients succumbed to complications of fat embolism. No event was described in the context of surgery. We want to raise awareness that spontaneous unnoticed fractures may occur especially in adolescents with DMD from traumatic injury of large bones and also during elective surgery with a high risk of causing fat embolism with severe sequelae.

A diagnostic strategy for pulmonary fat embolism based on routine H&E staining using computational pathology.

Pulmonary fat embolism (PFE) as a cause of death often occurs in trauma cases such as fractures and soft tissue contusions. Traditional PFE diagnosis relies on subjective methods and special stains like oil red O. This study utilizes computational pathology, combining digital pathology and deep learning algorithms, to precisely quantify fat emboli in whole slide images using conventional hematoxylin-eosin (H&E) staining. The results demonstrate deep learning's ability to identify fat droplet morphology in lung microvessels, achieving an area under the receiver operating characteristic (ROC) curve (AUC) of 0.98. The AI-quantified fat globules generally matched the Falzi scoring system with oil red O staining. The relative quantity of fat emboli against lung area was calculated by the algorithm, determining a diagnostic threshold of 8.275% for fatal PFE. A diagnostic strategy based on this threshold achieved a high AUC of 0.984, similar to manual identification with special stains but surpassing H&E staining. This demonstrates computational pathology's potential as an affordable, rapid, and precise method for fatal PFE diagnosis in forensic practice.