Predictive Factors for Post-Ischemic Compartment Syndrome in Non-Traumatic Acute Limb Ischemia in a Lower Extremity

Incidence of Compartment Syndrome Following Peri-Pandemic Intervention for Non-traumatic Acute Limb Ischemia

ObjectiveDuring the pandemic, our institution anecdotally observed a significant proportion of acute limb ischemia (ALI) patients developing compartment syndrome (CS) following revascularization compared to pre-pandemic rates. To determine whether this perceived increase was occurring globally, we utilized the TriNetX database to evaluate the incidence of CS secondary to ALI intervention in both the pre-pandemic (2017-2019) and pandemic eras (2020-2022).MethodsWe conducted a multicenter query using the TriNetX global research network for ALI patients receiving treatment. Incidence of CS diagnosis within 1 calendar day of ALI intervention was calculated for each era. Demographics and comorbidities were then compared between CS and non-CS patients within each era. Risk of adverse outcomes within 30 days of CS diagnosis was also determined for each era, including mortality, major amputation, and re-intervention.ResultsThe pre-pandemic cohort contained 7736 patients while the pandemic era cohort included 8,306, for 16,042 total patients. A significant increase in CS incidence (risk ratio (RR) = 1.23, P = 0.0026) was demonstrated within the pandemic era. An increased prevalence of comorbidities such as dyslipidemia (pre-pandemic: P = 0.0022; pandemic: P = 0.0026) and peripheral vascular disease (P < 0.0001, both eras) was observed in the non-CS cohort within both eras. 30-day mortality was significantly increased in CS patients (pre-pandemic: RR = 3.057; pandemic: RR = 2.710; P < 0.0001 both eras) compared to non-CS patients. CS patients were more likely to receive major amputation (pre-pandemic: RR = 3.734; pandemic: RR = 2.809; P < 0.0001 both eras) and/or re-intervention within 30 days (pre-pandemic: RR = 1.871, P < 0.0001; pandemic: RR = 1.370, P = 0.0218) over non-CS patients.ConclusionsThe incidence of CS following revascularization for ALI rose worldwide during the pandemic. Patients who developed CS are younger with fewer comorbidities than non-CS patients. Despite a more favorable comorbid profile, CS patients demonstrate significantly higher rates of adverse outcomes. Further investigation is necessary to determine the specific underlying mechanisms driving this increased incidence in CS among ALI patients.

Taohong Siwu Decoction Combined With the LncRNA H19/miR-675-5p Axis Repairs Limb Ischemia-Reperfusion Injury Through the Regulation of the Wnt3a/Ca2+ Signaling Pathway

Background: Taohong Siwu decoction (THSWT) has shown therapeutic effects on ischemia/reperfusion injury (IRI). This study tended to investigate the role of THSWT combined with the long non-coding RNA (LncRNA) H19 (H19)/miR-675-5p axis in improving limb IRI (LIRI). Methods: Hind LIRI rats and simulated IRI skeletal myoblasts models were constructed to evaluate the therapeutic effects of THSWT. The mechanism of THSWT treatment on LIRI was investigated by the regulation of the H19/miR-675-5p axis and the wingless/integrated (Wnt)/Ca2+ signaling pathway. Various assessments, such as H&E staining, TUNEL staining, flow cytometry, cell counting kit-8 (CCK-8) assay, quantitative real-time polymerase chain reaction (qRT-PCR), western blot, immunohistochemistry (IHC) staining, enzyme-linked immunosorbent assay (ELISA), biochemical assay, and calcium fluorescence imaging, were conducted to observe skeletal muscle injury, cell apoptosis, skeletal myoblast proliferation, gene and protein expressions, cytokine levels, glucose (Glu) uptake, and Ca2+ concentration. Results: THSWT intervention effectively improved skeletal muscle injury in LIRI rats, as evidenced by reduced muscle fiber damage and decreased cell apoptosis, accompanied by downregulation of H19, miR-675-5p, cleaved-Caspase3, Bax, PLC, and PKC expressions and upregulation of Bcl2 expression. Furthermore, silencing of H19 inhibited cell apoptosis of skeletal muscle and reduced IL-1β, IL-6, and TNF-α levels in LIRI rats. Notably, THSWT intervention combined with the silencing of H19 synergistically promoted the repair of skeletal muscle injury in LIRI rats. Mechanistically, THSWT intervention combined with regulation of the H19/miR-675-5p axis promoted the proliferation of skeletal myoblasts damaged by IRI through the Wnt3a/Ca2+ signaling pathway, increasing the levels of intracellular Bcl2, while decreasing the levels of Ca2+, CaMKⅡ, PLC, PKC, cleaved-Caspase3, Bax, TNF-α, IL-1β, IL-6, Wnt3a, and β-catenin. Conclusions: THSWT combined with the regulation of the H19/miR-675-5p axis effectively improved LIRI by modulating the Wnt3a/Ca2+ signaling pathway, providing insights for potential therapeutic strategies for LIRI.

Clinical value of foot thermometry in patients with acute limb ischemia

OBJECTIVE

We hypothesized that the severity of foot poikilothermy can be used for better differentiation of grades of acute limb ischemia. Thus, the study aim was evaluation of the value of non-contact foot thermometry, performed using a low-cost infrared medical thermometer, as an adjunct for clinical diagnosis of immediately threatened acute limb ischemia.

METHODS

It was a single-center observational prospective study performed over 3 years. Patients with acute limb ischemia of lower limbs grade I-IIB Rutherford treated with urgent revascularization were included. Grade of ischemia was determined independently by two experienced vascular surgeons. Thermometry of the ischemic foot was performed using a medical digital infrared non-contact thermometer (CK-T1501, Cooligg, China) with measuring accuracy of ±0.2°C. Temperature was measured in three points: the dorsal surface of the foot, plantar surface of the foot (both in the metatarsal region), and forehead. The maximal temperature gradient between patient's forehead and foot (∆Tmax F-F) was calculated. Measurements were repeated 6-12 h after revascularization.

RESULTS

A total of 147 patients were included. Only 3 (2%) patients presented rest pain without sensory loss and motor deficit, while the majority were diagnosed with mild (63/147, 42.8%) or moderate (27/147, 18.3%) motor deficit. The temperature of the ischemic foot varied from 20 to 36.1°C, while median value of the temperature was 26.7 [24.5-29.9] °C on the dorsal surface and 26.8 [24.5-29.6] °C on the plantar surface of the foot (p = 0.85). Patients with Grade IIB ischemia had significantly lower dorsal foot temperature, plantar foot temperature, and larger ∆Tmax F-F than the patients with grades I-IIA: 25.1 [23.9-26.8] °C versus 29.9 [27.6-30.8] °C; 25.2 [23.8-27.5] °C versus 29.6 [28-31.1] °C; and 11.6 [9.7-12.8] °C versus 7.2 [6-9] °C (p < 0.0001). Areas under ROC curve for diagnosis of Grade IIB ischemia were similar for dorsal foot temperature (0.82), plantar temperature (0.81), and ∆Tmax F-F (0.82). The best cutoff value by Youden was ≥9.5°C for ∆Tmax F-F, ≤26.8°C for dorsal, and ≤27.7°C for plantar temperature. Criterion ∆Tmax F-F offered the highest specificity of 86% (95%CI 74.2-93.7) and positive predictive value of 89.2% (95%CI 79.5-93.2), while plantar temperature offered sensitivity of 82.5% (95%CI 70.1-91.3) and negative predictive value of 69.1% (95%CI 57.6-83.2). In multivariate analysis including age, gender, and etiology of arterial occlusion, the criterion ∆Tmax F-F of ≥9.5°C was a unique variable significantly associated with risk of amputation (adjusted OR 2.6, 95%CI 1.2-5.9, p = 0.01).

CONCLUSION

Current study demonstrated that patients with immediately threatening ALI have significantly lower foot temperature than those with viable and marginally threatened limbs. Severe foot poikilothermy at admission is associated with poor outcomes of revascularization, mostly with limb loss.

Evaluation of Clinical and Venous Blood Parameters as Surrogate Indicators in Assessing the Need for Fasciotomy in Lower Limb Compartment Syndrome

Acute compartment syndrome in the lower limb, a surgical emergency, may cause ischemic damage to muscles and neurological deficits leading to loss of function of the limb which may even require amputation, thus drastically affecting the quality of life of a patient. Fasciotomy for decompression is suggested when the differential pressure in the compartment of the leg is ≤30 mm Hg. However, compartment pressure measurement is not always feasible. Surgeons often find themselves in a dilemma in deciding the right treatment option for the patient: fasciotomy or conservative management. Since there is no universally accepted reference standard for the diagnosis of acute compartment syndrome at present, there is a need for definitive diagnostic variables so as to not delay fasciotomy in patients who need it, as well as to avoid unnecessary fasciotomies, especially when compartment pressures cannot be measured. In this observational study including 71 patients, based on the compartment pressures of the affected limb, treatment was done either with fasciotomy or conservative approach, and various clinical and biochemical parameters were evaluated in between these two groups. Statistically significant difference was found in the venous blood gas parameters between patients managed conservatively and with fasciotomy (MANOVA, P = .001). The results revealed the association of lower venous blood bicarbonate levels (independent sample t test, P = .021) and the presence of paresthesia (Fisher exact test, P = .0016) with the fasciotomy group. Also, pain on passive stretching of the affected limb was found to be significantly associated with a delta pressure of ≤30 mm Hg in any compartment (Fisher exact test, P = .002). These variables may thus be used as an alternative to the measurement of compartment pressure to assess the requirement of fasciotomy.

Quantitative diagnosis of early acute compartment syndrome using two-dimensional shear wave elastography in a rabbit model

PURPOSE

This study explored the association of the elasticity modulus and shear wave velocity (SWV) of the tibialis anterior muscle, as measured by two-dimensional shear wave elastography (2D-SWE), with the intracompartmental pressure (ICP) determined using the Whitesides method in a New Zealand rabbit model of acute compartment syndrome (ACS). Additionally, it evaluated the viability of 2D-SWE as a noninvasive, quantitative tool for the early detection of ACS.

METHODS

An ACS model was established through direct external compression by applying pressure bandaging to the lower legs of 15 New Zealand rabbits using neonatal blood pressure cuffs. Another five animals represented a non-modeled control group. To measure the elasticity modulus and SWV of the tibialis anterior muscles, 2D-SWE was employed. Blood oxygen saturation, serum creatine kinase (CK), and myoglobin levels were monitored. Subsequently, the anterior tibial compartment was dissected, and the tibialis anterior was removed for hematoxylin and eosin staining to assess muscle injury.

RESULTS

The elasticity modulus and SWV of the tibialis anterior muscle increased with compression duration, as did serum CK and myoglobin levels. ICP was strongly positively correlated with these parameters, particularly mean velocity (r=0.942, P<0.001) and CK (r=0.942, P<0.001). Blood oxygen saturation was negatively correlated with ICP (r=-0.887, P<0.001). Histological analysis indicated progressive muscle cell swelling over time, with damage transitioning from reversible to irreversible and culminating in necrosis.

CONCLUSION

In a rabbit ACS model, ICP was strongly positively correlated with muscle elasticity modulus/SWV. Consequently, 2D-SWE may represent a novel tool for assessing early-phase ACS.

Vascular Complications in Extracorporeal Membrane Oxygenation-A Narrative Review

The establishment of a peripheral ECMO circuit can lead to significant arterial and venous complications in 10-30% of patients. Vascular complications, particularly acute limb ischemia, are associated with worsening overall outcomes. Limb ischemia occurs significantly more frequently in the early stages of VA ECMO than in VV ECMO. Mechanisms of limb ischemia include arterial obstruction, cannulation injury, loss of pulsatile flow, thromboembolism, venous stasis from compressive obstruction with large venous cannulas, and systemic vasoconstriction due to shock and pharmacologic vasoconstriction. The care team may use several mitigation strategies to prevent limb ischemia. Arterial and venous complications can be mitigated by careful access site selection, minimizing cannula size, placement of distal perfusion and/or outflow catheter(s), and continuous NIRS monitoring. Rapid intervention, when ischemia or compartment syndrome occurs, can reduce limb loss but may not affect the mortality and morbidity of the ECMO patient in the long term due to their underlying conditions and the etiology of the ECMO need.

Establishment and pathophysiological evaluation of a novel model of acute compartment syndrome in rats

BACKGROUND

Researches have used intra-compartmental infusion and ballon tourniquest to create high intra-compartmental pressure in animal models of Acute Compartment Syndrome (ACS). However, due to the large differences in the modeling methods and the evaluation criteria of ACS, further researches of its pathophysiology and pathogenesis are hindered. Currently, there is no ideal animal model for ACS and this study aimed to establish a reproducible, clinically relevant animal model.

METHODS

Blunt trauma and fracture were caused by the free falling of weights (0.5 kg, 1 kg, 2 kg) from a height of 40 cm onto the lower legs of rats, and the application of pressures of 100 mmHg, 200 mmHg, 300 mmHg and 400 mmHg to the lower limbs of rats using a modified pressurizing device for 6 h. The intra-compartmental pressure (ICP) and the pressure change (ΔP) of rats with single and combined injury were continuously recorded, and the pathophysiology of the rats was assessed based on serum biochemistry, histological and hemodynamic changes.

RESULTS

The ΔP caused by single injury method of different weights falling onto the lower leg did not meet the diagnosis criteria for ACS (< 30 mmHg). On the other hand, a combined injury method of a falling weight of 1.0 kg and the use of a pressurizing device with pressure of 300 mmHg or 400 mmHg for 6 h resulted in the desired ACS diagnosis criteria with a ΔP value of less than 30 mmHg. The serum analytes, histological damage score, and fibrosis level of the combined injury group were significantly increased compared with control group, while the blood flow was significantly decreased compared with control group.

CONCLUSION

We successfully established a new preclinical ACS-like rat model, by the compression of the lower leg of rats with 300 mmHg pressure for 6 h and blunt trauma by 1.0 kg weight falling.

Acute ischemia of the upper and lower limbs: Tailoring the treatment to the underlying etiology

Acute limb ischemia (ALI) can be a devastating clinical emergency with potentially limb- or life-threatening consequences. It is defined as a quickly developing or sudden decrease in limb perfusion producing new or worsening symptoms and signs, often threatening limb viability. ALI is commonly related to an acute arterial occlusion. Rarely, extensive venous occlusion can lead to upper and lower extremities ischemia (ie, phlegmasia). The incidence of acute peripheral arterial occlusion causing ALI is approximately 1.5 cases per 10,000 people per year. The clinical presentation depends on the etiology and whether the patient has underlying peripheral artery disease. Except for traumas, the most common etiologies are embolic or thrombotic events. Peripheral embolism, likely related to embolic heart disease, is the most common cause of acute upper extremity ischemia. However, an acute thrombotic event may occur in native arteries, at the site of a pre-existing atherosclerotic plaque, or as a failure of previous vascular interventions. The presence of an aneurysm may predispose to ALI for both embolic and thrombotic mechanisms. Immediate diagnosis, accurate assessment of limb viability, and prompt intervention, when needed, play important roles in salvaging the affected limb and preventing major amputation. Severity of symptoms is usually dependent on the amount of surrounding arterial collateralization, which may often reflect a pre-existing chronic vascular disease. For this reason, early recognition of the underlying etiology is crucial for choice of best management and definitely for treatment success. Any error in the initial evaluation may negatively affect the functional prognosis of the limb and endanger the patient's life. The aim of this article was to discuss diagnosis, etiology, pathophysiology, and treatment of patients with acute ischemia of the upper and lower limbs.

Necessity, Role, and Outcomes of Fasciotomy in Patients with Acute Limb Ischemia

BACKGROUND

The incidence of compartment syndrome in patients with acute lower limb ischemia (ALLI) and the effects of fasciotomy on outcomes are largely undefined. This study aimed to define the incidence of compartment syndrome in patients with ALLI and to examine whether different fasciotomy strategies are associated with specific patient outcomes.

METHODS

A single center retrospective study of patients who had ALLI between April 2016 and October 2020 at a tertiary care center. Patients were categorized into groups as having received early and late therapeutic fasciotomy (TF), early prophylactic fasciotomy (PF), early exploratory fasciotomy, and no fasciotomy. Primary outcome was 30-day amputation rate. Secondary outcomes were 30-day and 1-year mortality, 1-year amputation rate, and length of stay. Groups were compared using descriptive statistics to assess the association of fasciotomy approach with outcomes.

RESULTS

During the study period, 266 patients were treated for ALLI, and 62 patients (23%) underwent 66 fasciotomies. A total of 41 TF, 23 PF, and 2 exploratory fasciotomies were done. There were 58 early fasciotomies performed (88% of 66 limbs): 33 (57%) early TF, 23 (40%) PF, and 2 (3%) exploratory. There were 8 patients who developed compartment syndrome after their revascularization operation and received delayed TF (12% of 66 limbs). The total number of TF was 41, which was 15% of all ALLI patients. The mean ± SD time to fasciotomy closure was 6.7 ± 5.7 days, which did not differ between PF and TF groups. Significantly more patients in the TF had an amputation at 30 days (11 [29%] vs 1 [5%]; P = 0.03) and at 1 year (6 [18%] vs 2 [9%]; P = 0.02) than those in the PF group. Length of stay was increased in both TF (16 days) and PF (19 days) patients compared to non-fasciotomy patients (10 days; P < 0.01) but did not differ between the 2 fasciotomy groups (P = 0.4). Thirty-day limb loss was highest in patients who underwent early TF (10/33, 33%), intermediate in those with delayed TF (1/8, 13%), and lowest in PF (1/23, 5%; P = 0.03).

CONCLUSIONS

Approximately 15% of patients with ALLI in our cohort required a TF for compartment syndrome. Close postoperative monitoring of ALLI patients who did not undergo early fasciotomy did detect delayed CS; however, this approach did not prevent limb loss. To optimize limb salvage, physicians treating patients with ALLI should be experienced in how to recognize and treat compartment syndrome.

Mechanisms and Interventions on Acute Lower Limb Ischemia/Reperfusion Injury: A Review and Insights from Cell to Clinical Investigations

AIM

This review aims to highlight mechanistic insights on skeletal muscle ischemia/reperfusion injury (IRI), a potentially life-threatening complication after acute lower limb ischemia. Lower limb IRI produces a wide spectrum of manifestations, ranging from local skeletal muscle necrosis to multi-organ failure. There is increasing evidence from both in vitro and in vivo reports to demonstrate several promising interventions that have successfully reduced IRI in skeletal muscle ischemic models. However, clinical studies to confirm their benefits are still lacking.

METHOD

We conducted a comprehensive search of English literature listed in the PubMed database (All related published articles shown in PubMed until September 2020 have been included in this review), using the following keywords: acute limb ischemia, acute arterial occlusion, compartment syndrome, ischemic reperfusion injury, revascularization and hypoxic reoxygenation.

RESULT

58 articles pertinent to acute limb ischemia models were identified. The underlying mechanisms associated with IRI in skeletal muscle are due to excessive mitochondrial production of reactive oxygen species (ROS), cellular apoptosis and activation of inflammatory cascades. Several therapeutic interventions including both pharmacological and non-pharmacological treatments have been investigated and some showed promising results. These interventions include antioxidation, anti-inflammation, anti-hypertension, controlled-reperfusion and ischemic preconditioning. Further clinical studies are needed to warrant their use in a clinical setting for lower limb IRI treatment.

CONCLUSION

This review comprehensively summarizes the mechanisms underlying IRI in lower limb ischemia. The reports currently available regarding the potential therapeutic interventions against lower limb IRI from in vitro, in vivo and clinical studies are presented and discussed. These findings may provide mechanistic insights for devising the strategies to improve the clinical outcomes in IRI patients in the near future. Further clinical studies are needed to warrant their use in a clinical setting for lower limb IRI treatment.

Prognostic Risk Factors for the Development of Compartment Syndrome in Acute Lower Limb Ischemia Patients Treated with Catheter-Directed Thrombolysis

OBJECTIVE

To determine predisposing factors that may lead to the development of compartment syndrome (CS) in patients with acute lower limb ischemia (ALLI) managed with intra-arterial catheter-directed thrombolysis (CDT).

METHODS

This is a retrospective study of patients admitted between 01/2002 and 12/2015 to three university hospitals in Tampere, Turku, and Oulu, Finland, with acute or acute-on-chronic lower limb ischemia (Rutherford I-IIb). Patients managed with CDT and aspiration thrombectomies (AT) as an adjunct to CDT were included in the study. Multivariable binary logistic regression models were used to detect possible risk factors for the development of CS and its impact on the limb salvage and survival. Amputation-free survival (AFS) rates of CS and non-CS patients were compared using Kaplan-Meier survival analysis. The length of hospitalization was calculated and compared between the CS and non-CS groups.

RESULTS

A total of 292 CDTs with or without ATs were performed on patients with a mean age of 71 years (standard deviation 13 years), 151 (51.7%) being male. Altogether, 12/292 (4.1%) treatment-related CS cases were registered. Renal insufficiency (odds ratio [OR] 4.27, P = .07) was associated with an increased risk of CS. All CS cases were managed with fasciotomies. Treatment with fasciotomy was associated with a prolonged hospitalization of a median of 7 days versus the 4 days for non-CS patients, P < .001. During the median follow-up of 51 months (interquartile range 72 months), 152/292 (52.1%) patients died and 51/292 (17.5%) underwent major amputations. CS was not associated with an increased risk of mortality, but it was associated with a higher risk of major amputation (OR 3.87, P = .027). The AFS rates of patients with or without CS did not significantly differ from each other in the long term.

CONCLUSION

CS after CDT for the treatment of ALLI is uncommon. Renal insufficiency is associated with an increased risk of CS. Fasciotomy prolongs the hospitalization. Patients with CS are exposed to an increased risk of major amputation.

Developing an in-vivo physiological porcine model of inducing acute atraumatic compartment syndrome towards a non-invasive diagnosis using shear wave elastography

Compartment syndrome (CS) is a pathological event caused by elevated intracompartmental pressure (ICP); however, changes from the onset of inducing atraumatic CS remained unclear. The study aimed to investigate the physiological changes in a newly developed in vivo porcine acute atraumatic CS model. CS was induced by ischemia–reperfusion injury in the left hind leg of fourteen pigs divided into an echogenicity group (EG) and a shear wave elastography group (SEG). Echogenicity was measured in EG, and shear elastic modulus (SEM) was measured in SEG seven times before, at the onset of inducing CS, and every 30 min after the onset over eight hours. Simultaneously, ICP, blood pressure, and muscle perfusion pressure (MPP) were also measured in both groups. Our results indicate that SEM of the experimental leg in SEG significantly increased as CS developed compared to the control leg (p = 0.027), but no statistical difference in the echogenicity in EG was found between the experimental leg and control leg. There were also significant correlations between SEM and ICP (p < 0.001) and ICP and MPP (p < 0.001). Our method and findings can be a basis to develop a non-invasive diagnostic tool using a shear wave elastography for atraumatic CS.

Acute Compartment Syndrome Following Thrombolysis For Acute Lower Limb Ischemia

BACKGROUND

Acute Compartment syndrome (ACS) with subsequent need for fasciotomy is a serious and insidious complication after revascularization for acute lower limb ischemia (ALI). The development of ACS during endovascular catheter directed thrombolysis is particularly difficult to identify. The aim was to identify the incidence, predisposing factors, wound treatment, and outcome in terms of amputation and survival for patients presenting with ALI that develop ACS during catheter directed thrombolysis. Patients who did not develop ACS after thrombolysis were analyzed as controls.

METHODS

Descriptive retrospective analysis of prospective databases from two large tertiary-referral vascular centers. Patients with ACS after thrombolysis for ALI between 2001-2017 were analyzed.

RESULTS

Seventy-eight cases and 621 controls were identified. Mean age was 72 years and 30 (38.5%) were women in the ACS group. Patients that developed ACS presented with significantly more severe preoperative ischemia. With 38.5% having Rutherford 2b classification as compared to 22.7 % in the control group (P = 0.002). Occluded popliteal artery aneurysms were also associated with a higher incidence of ACS (P = 0.041). Treatment of the fasciotomy wound was most commonly treated with regular wound dressing in 45 (58%) of cases, while wound dressing and foot pump and vacuum assisted closure were used in 14 (18%) and 19 (24%) respectively. These differing approaches did not affect the number of wound infections and amputations, which was similar regardless of treatment type. Vacuum assisted closure was associated with a higher degree of skin graft closure (P = 0.001). The median time to complete wound closure was 10 days. One year after thrombolysis, the major amputation rate in the ACS group was 31% as opposed to 17% in control group, P = 0.003. Mortality measured at 16.7% and 15.3%, respectively, P = 0.872. Amputation-free survival in the ACS group was 62% vs. 73% in the control group, P = 0.035. These differences level out, however, when applying long-term analysis of amputation-free survival in Kaplan-Meier analysis (log-rank 0.103).

CONCLUSIONS

Patients that developed ACS during endovascular CDT presented with a more severe pre-operative ischemia, more occluded popliteal artery aneurysms and had a higher amputation rate during the first year, compared to controls. The development of ACS during endovascular treatment of ALI with thrombolysis is not uncommon and warrants both clinical awareness and rapid treatment.

Outcomes After Selective Fasciotomy for Revascularization of Nontraumatic Acute Lower Limb Ischemia

Objectives: Limited data support the use of fasciotomies in acute limb ischemia (ALI) in patients with isolated arterial occlusion. This study describes an experience in which fasciotomies are not regularly performed post-revascularization. Methods: Using International Classification of Diseases, Ninth and Tenth Edition codes, patients presenting to the University of California Davis Medical Center between January 2003 and July 2018 with ALI, excluding those with traumatic injuries were identified. The primary outcome was major amputation, and the secondary outcome was foot drop. Additionally, the characteristics of those patients in each category of ischemic severity excluding those with grade 3 ischemia were summarized. Results: Of the 253 patients identified, revascularization was successful in 230 patients with 11 total fasciotomies performed. One hundred thirty-five patients were Rutherford Class 1/2A and 95 were 2B. In those with 1/2A ischemia, 134 (102 had >6 hours of symptoms) did not undergo fasciotomy with only one amputation occurring in this group. In those with 2B ischemia, 65 had >6 hours of symptoms; 58 did not undergo fasciotomy with 4 major amputations. In the 30 patients with ≤6 hours of ischemic symptoms, 27 did not undergo fasciotomy with 1 major amputation occurring in this group. There were no amputations in those patients who underwent fasciotomies. Additionally, there were 14 patients with a foot drop, of which 11 were in patients with 2B ischemia without fasciotomy. Conclusions: The data suggest that regardless of ischemic duration, 1/2A patients may not need fasciotomies, while those patients with 2B ischemia may benefit.

Factors Associated With Poor Outcomes in Acute Forearm Compartment Syndrome

Background: There is limited literature on risk stratification of patients with acute forearm compartment syndrome. The primary objective of this study was to identify factors associated with poor outcomes in patients with acute forearm compartment syndrome. Methods: We retrospectively identified 130 patients with acute compartment syndrome of 130 forearms treated with fasciotomies from January 2000 to June 2015 at 2 Level 1 trauma centers. Poor outcome was defined as a composite variable, including: (1) death; (2) limb amputation; (3) persistent neurological deficit; and (4) contracture. Patient- and treatment-related variables were collected. Bivariate analyses were used to screen for variables associated with poor outcome, and explanatory variables with a value of P < .05 were included in our multivariable logistic regression analyses. Results: Of the 130 patients, 43 (33%) with acute forearm compartment syndrome had poor outcomes, including 5 deaths, 5 limb amputations, 21 persistent neurological deficits, and 31 contractures. Multivariable logistic regression analyses showed that elevated serum creatine kinase at presentation (P < .05) was associated with poor outcomes in patients with acute forearm compartment syndrome. Receiver operating characteristic curve analysis showed that a serum creatine kinase cutoff of 300 U/L yields 92% sensitivity and a serum creatine kinase cutoff of 10 000 U/L yields 95% specificity for poor outcomes in acute forearm compartment syndrome. Conclusions: Elevated creatine kinase levels above 300 U/L are a useful screening test for the highest risk patients with acute forearm compartment syndrome. Levels above 10 000 U/L may play a role in informed consent and counseling regarding expectations.

Risk Factors for Fasciotomy After Revascularization for Acute Lower Limb Ischaemia

Background: Acute lower limb ischaemia (ALI) is a life and limb threatening vascular emergency. Acute compartment syndrome (ACS) may develop upon revascularization. The risk of fasciotomy was hypothesized to be decreased in women due to their lower calf muscle mass. The main aim was to evaluate risk factors for fasciotomy after revascularization for ALI.

Methods: This is a retrospective observational study of patients undergoing revascularization for ALI between 2001 and 2018. Factors associated with outcome at 1 year in univariable analysis (p < 0.1) were chosen for multi-variable analysis and expressed in Odds Ratios (OR) with 95% confidence intervals (CI).

Results: The median age for women (n = 394) was 75 years and men (n = 449) was 70 years (p < 0.001). The frequency of fasciotomy was 10.0% (84/843). The median in-hospital stay was 28 vs. 6 days for patients undergoing fasciotomy and not, respectively (p < 0.001). In adjusted analysis, renal insufficiency (OR 1.77, 95% CI 1.04–3.01), motor deficit (OR 4.40, 95% CI 2.45–7.92), popliteal artery aneurysm thromboembolism (OR 2.26, 95% CI 1.06–4.80), and open vascular surgery (OR 3.43, 95% CI 1.97–5.98) were associated with an increased risk of fasciotomy. Female patients (OR 0.49, 95% CI 0.28–0.84) and anemia (OR 0.52, 95% CI 0.28–0.84) had a lower risk. The major amputation/mortality rate at 1-year was 27.7%; fasciotomy (OR 1.94, 95% CI 1.11–3.40), anemia (OR 1.84, 95% CI 1.24–2.73) and female gender (OR 1.44, 95% CI 1.00–2.08) were independently associated with an increased risk.

Conclusions: Female patients had lower rates of fasciotomies, but subsequent higher risk of major amputation/mortality, which may be attributed to inferior results of revascularization. Lower muscle mass and underdiagnosis of ACS could also explain the lower frequency of fasciotomy for female patients. Further studies are needed to better understand gender differences in presentation of ALI, revascularization results and diagnosis of ACS.

Factors associated with myonecrosis at time of fasciotomy in acute leg compartment syndrome

INTRODUCTION

The objective of this study is to determine factors associated with myonecrosis at the time of fasciotomy in patients with acute leg compartment syndrome.

METHODS

A retrospective cohort study was conducted of 546 patients with acute leg compartment syndrome treated with fasciotomies from January 2000 to June 2015 at two tertiary trauma centers. The main outcome measurement was clinical myonecrosis diagnosed by the treating surgeon at the time of fasciotomy.

RESULTS

Eighty-two patients (15.0%) with acute leg compartment syndrome had myonecrosis at time of fasciotomy. Multivariable logistic regression analyses showed that younger age (p = 0.004) and diabetes mellitus (p < 0.001) were associated with myonecrosis at time of fasciotomy in acute leg compartment syndrome. Serum creatine kinase at presentation greater than 2405 U/L was found to be associated with myonecrosis at time of fasciotomy in post hoc analysis (p < 0.001).

CONCLUSIONS

Myonecrosis is associated with patient-related factors. Younger age by 10 years is associated with a 1.3 times increase and diabetes mellitus with a 3-time increase in the odds of myonecrosis. Serum creatine kinase at presentation greater than 2405 U/L denotes an almost 3 times increase in odds of myonecrosis and may be useful for preoperative counseling.

Analysis of the Safety and Efficacy of the Endovascular Treatment for Acute Limb Ischemia with Percutaneous Pharmacomechanical Thrombectomy Compared with Catheter-Directed Thrombolysis

BACKGROUND

To evaluate the rates of limb salvage, survival, and perioperative mortality in patients with acute limb ischemia (ALI) submitted to endovascular revascularization with pharmacomechanical thrombectomy (PMT) and catheter-directed thrombolysis (CDT).

METHODS

This was a retrospective consecutive cohort study of patients with ALI who were submitted to endovascular treatment with PMT or fibrinolysis at the Division of Vascular and Endovascular Surgery, Hospital do Servidor Público Estadual (São Paulo, Brazil), between July 2015 and December 2018. The limb salvage rate and survival rate at 720 days were analyzed in both the PMT (group 1) and CDT treatment (group 2), as well as the perioperative mortality rate (PMR) at 30 days after surgery.

RESULTS

One hundred twelve patients were admitted to the emergency department with ALI between July 2015 and December 2018. Seventeen patients diagnosed with Rutherford III irreversible ALI and 46 patients submitted to open surgery were excluded. Thus, 49 patients were submitted to endovascular surgery; 18 (36.7%) were classified into group 1, and 31 (63.3%) were classified into group 2. The clinical data were equal between the 2 groups, but there was a higher prevalence of thrombophilia in group 1 (3 cases; P < 0.001). The limb salvage rate and the overall survival rate at 720 days were similar between groups 1 and 2 (87.8% vs. 89.7%, P = 0.78 and 84.7% vs. 69.2%, P = 0.82, respectively). There was no statistical difference regarding secondary patency rates at 720 days between groups 1 and 2 (group 1, 81.9% and group 2, 78.8%; P = 0.66). The PMR was 16.7% (8 patients) within the first 30 days. Group 2 had a higher overall mortality rate (OMR) (6 patients, 19.3%, P = 0.03). Regarding the PMT group, there was a higher rate of complications such as myoglobinuria, hematuria, acute renal failure, and death in the subgroup of patients in whom there were performed more than 150 cycles/sec during the surgery (P < 0.001).

CONCLUSIONS

In the present study, the PMT and CDT endovascular procedures had similar limb salvage, overall survival, and secondary patency rates. However, the OMR was higher in the CDT group. Another important finding was related to the number of cycles/sec performed in the PMT group, in whom patients with more than 150 cycles/sec have presented with higher rates of hematuria, myoglobinuria, acute renal failure, and death.

A silent compartment syndrome following elective minimally invasive mitral valve repair

A 63-year-old male with severe mitral valve regurgitation underwent an elective minimally invasive mitral valve repair. Peripheral cannulation of the right femoral vein and artery was performed with a total cardiopulmonary bypass time of 268 min. There were no intraoperative complications. 12 hours postoperatively the patient reported mild pain in the right lower leg with a subjective decrease in sensation. Compartmental pressures were significantly raised. The patient underwent lower leg fasciotomies, which revealed bulging compartments confirming the diagnosis of an evolving compartment syndrome (CS). This rare case demonstrates the highly variable aetiology, pathophysiology and presenting symptoms of CS. Clinicians in any specialty should consider this diagnosis if there is a possibility of local vascular compromise secondary to an intervention/treatment. This diagnosis is not exclusive to patients with trauma and as such clinicians should have a high index of suspicion for this potentially devastating condition.

Guidewire perforation and compartment syndrome after lower extremity angioplasty

Chronic total occlusion remains one of the most challenging lesions to treat despite continuing developments in medical devices and increasing operator experience. Guidewire perforation complications are being increasingly observed. Early recognition and timely institution of appropriate treatment are essential to prevent potentially devastating sequelae.