Continual near-infrared spectroscopy monitoring in the injured lower limb and acute compartment syndrome: an FDA-IDE trial

[Diagnostics of acute compartment syndrome : Current gold standard and the state of science of noninvasive assessment methods]

Acute compartment syndrome (ACS) is defined by a disorder of the microcirculation due to a persistent pathological pressure increase within a muscle compartment. The ischemia of the tissue leads to an initially reversible functional impairment and finally irreversible damage of the musculature, nerves and other structures. Based on the understanding of the pathophysiology, the current diagnostic concepts and treatment using the so-called dermatofasciotomy of the affected muscle compartments can be derived. In addition to the suspicion of a possible ACS based on the medical history of the patient, the findings of the clinical examination are decisive. This review article gives a summary of all the essential aspects of the diagnostics. In clinically uncertain cases and for monitoring, an objectification of the findings using instrument-based techniques is increasingly required. Nowadays, invasive needle pressure measurement is available; however, due to limited reliability, specificity and sensitivity, these measurements only represent an aid to decision guidance supporting or advising against the indications for dermatofasciotomy. The increasing demands on making a certain diagnosis and justification of a surgical intervention from a legal point of view, substantiate the numerous scientific efforts to develop noninvasive instrument-based diagnostics. These methods are based either on detection of increasing intracompartmental pressure or decreasing perfusion pressure and microcirculation. The various measurement principles are summarized in a lucid form.

Comparison and convergence of compartment syndrome techniques: a narrative review

INTRODUCTION

Compartment syndrome (CS) continues to be a legitimate orthopedic emergency as it leads to thousands of amputations and permanent nerve and tissue damage to undiagnosed patients for more than eight hours. In CS, intracompartmental pressure is elevated, causing reduced blood flow inside the limb compartments. An erroneous diagnosis may result in unnecessary fasciotomies, the only treatment for this condition.

AREAS COVERED

This review examines the previous and current diagnostic and therapeutic practices for compartment syndrome. It also performs a comparative analysis of each diagnostic technique and its foresights.

EXPERT OPINION

Currently, most clinicians rely on a physical examination of the patient to diagnose CS. The primary reason for the physical examination is the lack of a gold-standard device. The invasive intracompartmental pressure (ICP) measurement technique is still the most commonly used. On the other hand, many non-invasive approaches have the potential to be used as diagnostic tools; however, more research is needed before they can be accepted as standard clinical approaches.

Anesthetic management of external iliac artery transection in a morbidly obese patient with Klippel-Trenaunay-Weber syndrome: a case report

BACKGROUND

We report the anesthetic management of an external iliac artery transection in a morbidly obese patient with Klippel-Trenaunay-Weber syndrome (KTWS).

CASE PRESENTATION

A 47-year-old man with KTWS was scheduled for a right external iliac artery transection. Preoperative CT showed a right external iliac artery aneurysm, a right superficial femoral artery aneurysm, and developed collateral vessels. General anesthesia was maintained with desflurane, remifentanil, and rocuronium bromide. After the transection of the right external iliac artery, the regional saturation of oxygen (rSO₂) value of the right femoral did not decrease. There was no significant hemodynamic change before or after the transection. A non-ultrasound-guided rectus abdominis sheath block was performed due to the many collateral vessels. After extubation, the patient did not complain of postoperative pain.

CONCLUSIONS

In the transection of lower-extremity blood arteries under laparotomy in patients with KTWS, rSO₂ monitoring, hemodynamic monitoring, and combined regional anesthesia could be useful.

Percutaneously introduced wireless intramuscular near-infrared spectroscopy device detects muscle oxygenation changes in porcine model of lower extremity compartment syndrome

Serial examination and direct measurement of intracompartmental pressure (ICP) are suboptimal strategies for the detection of acute compartment syndrome (CS) because they are operator-dependent and yield information that only indirectly reflects intracompartmental muscle perfusion. As a result, instances of unnecessary fasciotomy and unrecognized CS are relatively common. Recently, near-infrared spectroscopy (NIRS)-based systems for compartment monitoring have generated interest as an adjunct tool. Under ideal conditions, NIRS directly measures the oxygenation of intracompartmental muscle (StO₂ ), thereby obviating the challenges of interpreting equivocal clinical examination or ICP data. Despite these potential advantages, existing NIRS sensors are plagued by technical difficulties that limit clinical utility. Most of these limitations relate to their transcutaneous design that makes them susceptible to both interference from intervening skin/subcutaneous tissue, underlying hematoma, and instability of the skin-sensor interface. Here, we present a flexible, wireless, Bluetooth-enabled, percutaneously introducible intramuscular NIRS device that directly and continuously measures the StO₂ of intracompartmental muscle. Proof of concept for this device is demonstrated in a swine lower extremity balloon compression model of acute CS, wherein we simultaneously track muscle oxygenation, ICP, and compartment perfusion pressure (PP). The observed StO₂ decreased with increasing ICP and decreasing PP and then recovered following pressure reduction. The mean change in StO₂ as the PP was decreased from baseline to 30 mmHg was -7.6%. The mean difference between baseline and nadir StO₂ was -17.4%. Cross-correlations (absolute value) describing the correspondence between StO₂ and ICP were >0.73. This novel intramuscular NIRS device identifies decreased muscle perfusion in the setting of evolving CS.

Forearm Compartment Pressure Change in Children Operated for Supracondylar Humerus Fracture

BACKGROUND

The aim of this study is to examine the preoperative and postoperative forearm compartment pressures in patients treated operatively for Gartland type III extension type supracondyler humerus fractures and understand the course of these values over postoperative period.

METHODS

Deep volar compartment pressure of 31 patients were measured in the proximal one third of the forearm preoperatively, and measurements were continued every 4 hours for the first 24 hours after the operation with a catheter. Type of the reduction technique (open reduction vs. closed reduction), duration of surgery, the time from the injury to surgery were all evaluated.

RESULTS

In the measurements made immediately after the operation (0 h), a sudden increase in the compartment pressure was detected in all patients (15.0±5.9 to 27.9±7.5 mm Hg) independent of the reduction technique and gradually decreased over time. The mean compartment pressure at the 12th hour postoperatively was higher in the open reduction group than in the CR group (24.5±3.4, 20.7±6.7 mm Hg, respectively) ( P =0.044). The mean preoperative compartment pressure was 17.7±5.8 mm Hg in patients with a time from injury to surgery longer than 12 hours, and 12.4±4.8 mm Hg in patients with 12 hours or less ( P =0.006). The postoperative 0-, 12-, and 20-hour pressure values were higher in the >1 hour operation time group than in the ≤1 hour group and the differences were statistically significant ( P =0.046, 0.016, and 0.032, respectively).

CONCLUSIONS

In pediatric supracondylar humeral fractures, those who underwent open reduction had higher preoperative and postoperative compartment pressures. The reduction attempt was found to be a factor that increased the compartment pressure and after the operation, the compartment pressure values decrease gradually. Prolonged operative time (>1 h) and increased time from injury to operative fixation (>12 h) were associated with higher compartment pressures.

LEVEL OF EVIDENCE

Level II-prospective study.

Extremity compartment syndrome: A review with a focus on non-invasive methods of diagnosis

The article deals with an overview of acute extremity compartment syndrome with a focus on the option of non-invasive detection of the syndrome. Acute extremity compartment syndrome (ECS) is an urgent complication that occurs most often in fractures or high-energy injuries. There is still no reliable method for detecting ECS. The only objective measurement method used in clinical practice is an invasive measurement of intramuscular pressure (IMP). The purpose of this paper is to summarize the current state of research into non-invasive measurement methods that could allow simple and reliable continuous monitoring of patients at risk of developing ECS. Clinical trials are currently underway to verify the suitability of the most studied method, near-infrared spectroscopy (NIRS), which is a method for measuring the local oxygenation of muscle compartments. Less explored methods include the use of ultrasound, ultrasound elastography, bioimpedance measurements, and quantitative tissue hardness measurements. Finding a suitable method for continuous non-invasive monitoring of the syndrome would greatly improve the quality of care for patients at risk. ECS must be diagnosed quickly and accurately to prevent irreversible tissue damage that can occur within hours of syndrome onset and may even warrant amputation if neglected.

Embryonic stem cell-derived mesenchymal stem cells alleviate skeletal muscle injury induced by acute compartment syndrome

Background

Acute compartment syndrome (ACS), a well-known complication of musculoskeletal injury, results in muscle necrosis and cell death. Embryonic stem cell-derived mesenchymal stem cells (ESC-MSCs) have been shown to be a promising therapy for ACS. However, their effectiveness and potentially protective mechanism remain unknown. The present study was designed to investigate the efficacy and underlying mechanism of ESC-MSCs in ACS-induced skeletal muscle injury.

Method

A total of 168 male Sprague–Dawley (SD) rats underwent 2 h of intracompartmental pressure elevation by saline infusion into the anterior compartment of the left hindlimb to establish the ACS model. ESC-MSCs were differentiated from the human embryonic stem cell (ESC) line H9. A dose of 1.2 × 10⁶ of ESC-MSCs was intravenously injected during fasciotomy. Post-ACS assessments included skeletal edema index, serum indicators, histological analysis, apoptosis, fibrosis, regeneration, and functional recovery of skeletal muscle. Then, fluorescence microscopy was used to observe the distribution of labeled ESC-MSCs in vivo, and western blotting and immunofluorescence analyses were performed to examine macrophages infiltration in skeletal muscle. Finally, we used liposomal clodronate to deplete macrophages and reassess skeletal muscle injury in response to ESC-MSC therapy.

Result

ESC-MSCs significantly reduced systemic inflammatory responses, ACS-induced skeletal muscle edema, and cell apoptosis. In addition, ESC-MSCs inhibited skeletal muscle fibrosis and increased regeneration and functional recovery of skeletal muscle after ACS. The beneficial effects of ESC-MSCs on ACS-induced skeletal muscle injury were accompanied by a decrease in CD86-positive M1 macrophage polarization and an increase in CD206-positive M2 macrophage polarization. After depleting macrophages with liposomal clodronate, the beneficial effects of ESC-MSCs were attenuated.

Conclusion

Our findings suggest that embryonic stem cell-derived mesenchymal stem cells infusion could effectively alleviate ACS-induced skeletal muscle injury, in which the beneficial effects were related to the regulation of macrophages polarization.

Tibial shaft fractures - to monitor or not? a multi-centre 2 year comparative study assessing the diagnosis of compartment syndrome in patients with tibial diaphyseal fractures

AIMS

The aim of this study was to compare the outcome in patients who did and did not undergo continuous compartment pressure monitoring (CCPM) following a tibial diaphyseal fracture.

PATIENTS AND METHODS

We performed a retrospective cohort study of 287 patients with an acute tibial diaphyseal fractures who presented to three centres over a two-year period. Demographic data, diagnosis, management, wound closure, complications, and subsequent surgeries were recorded. The primary outcome measure was the rate of short-term complications. Secondary outcomes were time to fasciotomy and split-skin grafting rates.

RESULTS

Of the 287 patients in the study cohort, 171 patients underwent CCPM (monitored group; MG) and 116 did not (non-monitored group; NMG). There were 21 patients who developed ACS and underwent fasciotomy, with comparable rates in both groups (n=13 in the MG vs n=8 in NMG; p=0.82). There was no difference in the rate of complications between groups (all p>0.05). The mean time from admission to fasciotomy was 22.1hrs, with a mean time of 19.8hrs in the MG and 25.8hrs in the NMG (mean difference, 6hrs; p=0.301). One patient in the NMG required a below-knee amputation. There was a trend towards a reduced requirement for split-skin grafting post decompression in the MG (15% vs 50%; p=0.14).

CONCLUSION

This study found no difference in the short-term complication rates in those patients that underwent CCPM and those that did not following a fracture of the tibial diaphysis. CCPM does appear to be safe with no increase in the rate of fasciotomies performed. There was a trend towards a reduced time to fasciotomy and a reduced rate of split skin grafting for wound closure with CCPM.

LEVEL OF EVIDENCE

Level III (Diagnostic: Retrospective cohort study).

Diagnosing acute compartment syndrome-where have we got to?

Purpose

Acute compartment syndrome is a condition whereby tissue ischaemia occurs due to increased pressure in a closed myofascial compartment. It is a surgical emergency, with rapid recognition and treatment—the keys to good outcomes.

Methods

The available literature on diagnostic aids was reviewed by one of the senior authors 15 years ago. Now, we have further reviewed the literature, to aim to ascertain what progress has been made.

Results

In this review, we present the evidence around a variety of available diagnostic options when investigating a potential case of acute compartment syndrome, including those looking at pressure changes, localised oxygenation, perfusion, metabolic changes and available blood serum biomarkers.

Conclusions

A significant amount of work has been put into developing modalities of diagnosis for acute compartment syndrome in the last 15 years. There is a lot of promising outcomes being reported; however, there is yet to be any conclusive evidence to suggest that they should be used over intracompartmental pressure measurement, which remains the gold standard. However, clinicians should be cognizant that compartment pressure monitoring lacks diagnostic specificity, and could lead to unnecessary fasciotomy when used as the sole criterion for diagnosis. Therefore, pressure monitoring is ideally used in situations where clinical suspicion is raised.

Compartment Syndrome of the Foot: An Evidence-Based Review

Compartment syndrome of the foot (CSF) is a surgical emergency, with high risk of morbidity and poor outcome, including persistent neurologic deficits or amputation. Uncertainty remains regarding surgical approaches, pressure monitoring values, and the extent of surgical treatment. This review provides a summary of the current knowledge and reports evidence-based diagnostic and therapeutic management options for CSF. Articles describing CSF were identified from MEDLINE, PubMed, and Cochrane databases up until February 2018. Experimental and original articles, systematic and nonsystematic reviews, case reports, and book chapters, independent of their level of evidence, were included. Crush injuries are the leading cause of CSF, but CSF can present after fractures of the tarsal or metatarsal bones and dislocations of the Lisfranc or Chopart joints. CSF is often associated with persistent neurologic deficits, claw toes, amputations, and skin healing problems. Diagnosis is made after accurate clinical evaluation combined with intracompartmental pressure monitoring. A threshold value of <20 mmHg difference between the diastolic blood pressure and the intracompartmental pressure is considered diagnostic. Management consists of surgery, whereby 2 dorsal incisions are combined with a medioplantar incision to the calcaneal compartment. The calcaneal compartment can serve as an "indicator compartment," as the highest-pressure values can regularly be measured within this compartment. Appropriately powered studies of CSF are necessary to further evaluate and compare diagnostic and therapeutic options.

Compartment pressures in children with normal and fractured lower extremities

PURPOSE

Needle manometry is a tool to confirm suspected acute compartment syndrome (ACS). There is scarce evidence of normal pressure values of the lower extremities in children. The aim of this study is to assess the normal compartment pressures in non-injured lower extremities of children.

METHODS

This prospective study included children up to the age of 16 years with lower extremity fractures that needed reduction. Between June 2009 and August 2015, 20 children were included. We used needle manometry to measure the pressures in the superficial (SPC), deep posterior (DPC) and in the anterior compartments (AC) on both the lower legs.

RESULTS

On the healthy leg, the mean compartment pressure was 15.15 mmHg in the AC (range 7-30 mmHg), 14.32 mmHg in the SPC (range 8-24 mmHg) and 13.00 mmHg in the DPC (range 4-21 mmHg). On the injured leg, the mean compartment pressure was 24.07 mmHg in the AC (range 5-40 mmHg), 17.21 mmHg in the SPC (range 7-29 mmHg) and 17.13 mmHg in the DPC (range 6-37 mmHg). We found a perfusion gradient (diastolic blood pressure-compartment pressure) < 30 mmHg in at least one compartment of the fractured and healthy leg in 13 patients. Five patients underwent fasciotomy for suspected ACS and their data was excluded for the injured leg.

CONCLUSION

We could show that children have higher normal compartment pressures than adults in the lower leg. They seem to be able to tolerate higher absolute compartment pressures and lower pressure gradients before ACS occurs. More studies are needed to make a final statement on tolerable compartment pressures in children.