Use of a disposable vascular pressure device to guide balloon inflation of resuscitative endovascular balloon occlusion of the aorta: a bench study

Resuscitative endovascular balloon occlusion of the aorta (REBOA) for rapid hemorrhage control is increasingly being used in trauma management. Its beneficial hemodynamic effects on unstable patients beyond temporal hemostasis has led to growing interest in its use in other patient populations, such as during cardiac arrest from nontraumatic causes. The ability to insert the catheters without fluoroscopic guidance makes the technique available in the prehospital setting. However, in addition to correct positioning, challenges include reliably achieving aortic occlusion while minimizing the risk of balloon rupture. Without fluoroscopic control, inflation of the balloon relies on estimated aortic diameters and on the disappearing pulse in the contralateral femoral artery. In the case of cardiac arrest or absent palpable pulses, balloon inflation is associated with excess risk of overinflation and adverse events (vessel damage, balloon rupture). In this bench study, we examined how the pressure in the balloon is related to the surrounding blood pressure and the balloon's contact with the vessel wall in two sets of experiments, including a pulsatile circulation model. With this data, we developed a rule of thumb to guide balloon inflation of the ER-REBOA catheter with a simple disposable pressure-reading device (COMPASS). We recommend slowly filling the balloon with saline until the measured balloon pressure is 160 mmHg, or 16 mL of saline have been used. If after 16 mL the balloon pressure is still below 160 mmHg, saline should be added in 1-mL increments, which increases the pressure target about 10 mmHg at each step, until the maximum balloon pressure is reached at 240 mmHg (= 24 mL inflation volume). A balloon pressure greater than 250 mmHg indicates overinflation. With this rule and a disposable pressure-reading device (COMPASS), ER-REBOA balloons can be safely filled in austere environments where fluoroscopy is unavailable. Pressure monitoring of the balloon allows for recognition of unintended deflation or rupture of the balloon.

Endoscopic retrieval of ingested magnets in children and role of magnetic retrievers

Background Various high-powered magnetic toy sets constitute a major hazard as the small magnets can be easily swallowed or aspirated by young children. Multiple ingested magnets or the ingestion of a magnet with another metallic object can pose a serious threat as this may lead to bowel perforation, fistulation, intestinal volvulus, bowel obstruction and death. Main body Retrieval of ingested magnets from the stomach is routinely performed endoscopically but can become a painstaking quest involving many tedious attempts to secure the magnet(s). Historically, pre-routine endoscopy, magnetic retrievers were used under fluoroscopic control for the removal of metallic objects in the stomach. With the advent of endoscopic retrieval instruments, they fell out of favour and are no longer readily available on the market. Despite this, conventional endoscopic instruments are likely to be less effective than endoscopic-assisted magnetic retrievers due to confounding weak bonds which form between the metal retrieval device and the magnet. Preoperative testing, and selection of the retrieval instrument with the strongest coupling effect with a magnet, might be beneficial. A simple, endoscopic-assisted magnetic retriever created in theatre can allow for more effective, time-efficient and safe removal of ingested magnets under direct vision. Conclusion Urgent removal of multiple ingested magnets or a single ingested magnet coupled with another ingested metallic object should be highlighted. Stricter implementation of a widespread ban over loose magnetic toys is needed. Standardised protocols for the surgical management of ingested magnets should be available in every hospital.

Perforated flexible catheters improve joint fluid aspiration in shoulder cadavers

A fluoroscopically controlled anterior approach in supine position is often used for arthrocentesis of the shoulder, but can lead to a high rate of dry aspirations. The aim of this study was to compare the aspiration performance of rigid needles and flexible catheters used with this approach. We hypothesized that a flexible catheter can significantly improve the amount of the obtained fluid. The glenohumeral joint of ten human cadaveric shoulder specimens were sequentially filled with 5, 10, 20 and 30 mL of contrast agent. For each volume the maximum aspirated amount of contrast agent with 4 different aspiration devices (20 gauge needle, 16 gauge needle, 16 gauge flexible catheter and 16 gauge perforated flexible catheter) were compared. All aspirations were done in supine cadaver position from anterior under fluoroscopic control. The aspirated amount of fluid was significantly higher using the 16 gauge perforated flexible catheter (p = 0.002–0.028) compared with all other devices when 5, 10 and 20 mL of contrast agent were in the joint. This perforated flexible catheter aspirated 80–96% of the available fluid while the standard 20 gauge needle aspirated 40–60%. Using a 16 gauge perforated flexible catheter in a supine anterior arthrocentesis technique results in aspiration of most of the fluid in human cadaveric shoulder specimens, while standard needles aspirate only about 50% of it. This can be clinically relevant when there is very little synovial fluid available and might reduce the number of insufficient aspirations.

CT based PSI blocks for osteotomies around the knee provide accurate results when intraoperative imaging is used

Purpose Correction osteotomies around the knee are common methods for the treatment of varus or valgus malalignment of the lower extremity. In recent years, patient specific instrumentation (PSI) guides were introduced in order to enhance the accuracy of these procedures. The purpose of this study was to determine the accuracy of CT based PSI guides for correction osteotomies around the knee of low volume osteotomy surgeons and to evaluate if CT based PSI blocks deliver a high degree of accuracy without using intraoperative fluoroscopy. Methods Two study arms with CT based PSI cutting blocks for osteotomies around the knee were conducted. Part one: A retrospective analysis of 19 osteotomies was made in order to evaluate the accuracy in the hands of a low volume surgeon on long-leg radiographs. Part two: A cadaveric study with 8 knees was performed for the purpose of analyzing the accuracy without using intraoperative fluoroscopy on pre- and postoperative CT scans. Hip-Knee-Ankle angle (HKA), lateral distal femoral angle (LDFA) and medial proximal tibial angle (MPTA) were analyzed. The mean absolute delta (∂) between the planned and postoperative parameters were calculated. The accuracy of both study arms were compared. Results Part one: The mean MPTA ∂, LDFA ∂ and HKA ∂ was 0.9°, 1.9° and 1.5°, respectively. Part two: The mean MPTA ∂ and LDFA ∂ was 3.5° and 2.2°, respectively. The mean ∂ of MPTA is significantly different between clinical patients with fluoroscopic control and cadaveric specimens without fluoroscopic control (P < 0.001). All surgeries were performed without complications such as a hinge fracture. Conclusion The clinical use of PSI guides for osteotomies around the knee in the hands of low volume surgeons is a safe procedure. The PSI guides deliver a reliable accuracy under fluoroscopic control whereas their non-use of intraoperative fluoroscopy leads to a lack of accuracy. The use of fluoroscopic control during PSI guided correction osteotomies is highly recommended. Level of evidence IV – Retrospective and experimental Study

Hip arthroscopy via a peripheral compartment first capsular-preserving technique: a step-by-step description

Hip arthroscopy is a well-recognized procedure for the treatment of several hip pathologies. Different methods of arthroscopic access to the hip have been published. The most popular approach is the central compartment first technique, where the first portal to the central compartment is placed under traction and fluoroscopic control. This technique, however, carries the risk of iatrogenic damage to the cartilage and labrum, especially when adequate distraction cannot be obtained. In addition, secondary exposure of the peripheral compartment frequently requires larger capsulotomies. The current article is to describe an alternative arthroscopic approach to the hip with the peripheral compartment being first accessed. The peripheral compartment first technique offers the advantages of a limited capsular release for peripheral compartment exposure and a reduced risk of iatrogenic cartilage and labrum damage during subsequent central compartment portal placement.

A ureteral single-J stent in the right atrium: a case report

Background J stents are commonly used to support the continuity of the urinary tract. Although intravascular, and more specific intracardiac, migrations have been described, they remain infrequent and unrecognized. Case report We report the case of a 57-year-old Caucasian woman with an intracardial migration of a single-J stent after pelvic exenteration. The intracardiac presence of single-J stent was probably due to a perioperative misplacement of the stent in the left ovarian vein. Retrieval was done under fluoroscopic control without any adverse events. Conclusions Intravascular migration of urological stents is uncommon but can cause serious morbidities and even mortality. Perioperative precautions must be taken to avoid this problem. In case of migration, early diagnosis and management are primordial and involve a multidisciplinary approach.

Abstract TP280: A Bland-new Rat Model of Embolic Cerebral Ischemia Using Micro Catheter Under Fluoroscopic Guide

Background: The failure of clinical trials on neuroprotective treatment may be partially caused by unestablished animal models. To verify a trans-arterial regeneration therapy, our project is aimed at developing a brand-new focal stroke model using micro catheter. Methods: Using Sprague-Dawley rats (n=8), a micro catheter (ID 0.26mm, OD 0.35mm) was navigated from the caudal ventral artery to the middle cerebral artery in order to establish local occlusion under digital subtraction angiography apparatus. Results: We succeeded in brain angiography by percutaneous tail artery puncture and occlusion of the middle cerebral artery by a radiopaque micro bead with 6 rats (75%). Ischemic stroke lesion volume is 480.3 mm3±84.2 mm3 on sustained 1% TTC solution after 24 hours occlusion. Conclusion: We present a new rat model for focal stroke using micro catheter under fluoroscopic control. The model is capable of repeated super selective administration of therapeutics directly to cerebral artery, and practice the 3Rs principles in experimental animals because of minimal invasive.Figure Legend- A: A sheath is inserted through the ventral midline, approximately 5 cm from the root of the tail of the rat, with a sharp angle. B: Cerebral angiography of rats. Arrowhead pointe middle cerebral artery. C: Occlusion of the middle cerebral artery by a radiopaque micro bead (arrowhead). D: Brain is sliced and stained 1% TTC solution after 24 hours occlusion.

Fluoroscopic Epidural Steroid Injection: Pain Relief in Discogenic Sciatica Versus Lumbar Spinal Stenosis. A Study on Middle Eastern Patients

Objective: To compare the effect of epidural steroid injections (ESI) in patients with discogenic sciatica (Sci) versus patients with lumbar canal stenosis (LSS), not controlled by conservative treatment. Materials and methods: In our study, 80 patients with Sci and 66 with LSS were included. A single ESI (10 mg dexamethasone in 3 cc 0.25% bupivacaine) was applied under fluoroscopic control: one level above the highest stenotic level, in the posterior epidural space, via interlaminar approach in LSS and at the prolapse level, in the anterior epidural space, via transforaminal route in Sci. Pain intensity was assessed by VAS at baseline and on days 1, 15 and 30 after intervention. Results: The procedure was successful in 78 Sci and 63 LSS patients. Patients with Sci responded significantly better. At one month, pain reduction over 50% was achieved in 63% (52.3–73.7% at p = 0.95) of Sci but only in 35% (23.2–46.8%) of LSS (p = 0.03). Return to pre-intervention level happened in 47% (34.7–59.3%) of LSS versus 14% (6.3–21.7%) of Sci patients (p = 0.01). In 5 patients the procedure failed, without resulting morbidity. Conclusion: ESI are more effective in patients with Sci than in single level LSS. In multiple level LSS, results are disappointing.

Fluoroscopically guided acetabular posterior column screw fixation via an anterior approach

Objective Safe posterior column screw fixation via an anterior approach under two-dimensional fluoroscopic control. Indications Anterior column with posterior hemitransverse fractures (ACPHF); transverse fractures; two-column fractures and T‑type fractures without relevant residual displacement of the posterior column after reduction of the anterior column and the quadrilateral plate. Contraindication Acetabular fractures requiring direct open reduction via a posterior approach; very narrow osseous corridor in preoperative planning; insufficient intraoperative fluoroscopic visualization of the anatomical landmarks. Surgical technique Preoperative planning of the starting point and screw trajectory using a standard pelvic CT scan and a multiplanar reconstruction tool. Intraoperative fluoroscopically controlled identification of the starting point using the anterior–posterior (ap) view. Advancing the guidewire under fluoroscopic control using the lateral–oblique view. Lag screw fixation of the posterior column with cannulated screws. Postoperative management Partial weight bearing as advised by the surgeon. Postoperative CT scan for the assessment of screw position and quality of reduction of the posterior column. Generally no implant removal. Results In a series of 100 pelvic CT scans, the mean posterior angle of the ideal posterior column screw trajectory was 28.0° (range 11.1–46.2°) to the coronal plane and the mean medial angle was 21.6° (range 8.0–35.0°) to the sagittal plane. The maximum screw length was 106.3 mm (range 82.1–135.0 mm). Twelve patients were included in this study: 10 ACPHF and 2 transverse fractures. The residual maximum displacement of the posterior column fracture component in the postoperative CT scan was 1.4 mm (0–4 mm). There was one intraarticular screw penetration and one perforation of the cortical bone in the transition zone between the posterior column and the sciatic tuber without neurological impairment.