Vascular Manipulation Research Articles

What an anesthesiologist should know about pediatric arrhythmias.

Identifying and treating pediatric arrhythmias is essential for pediatric anesthesiologists. Pediatric patients can present with narrow or wide complex tachycardias, though the former is more common. Patients with inherited channelopathies or cardiomyopathies are at increased risk. Since most pediatric patients present for anesthesia without a baseline electrocardiogram, the first identification of an arrhythmia may occur under general anesthesia. Supraventricular tachycardia, the most common pediatric tachyarrhythmia, represents a broad category of predominately narrow complex tachycardias. Stimulating events including intubation, vascular guidewire manipulation, and surgical stimulation can trigger episodes. Valsalva maneuvers are unreliable as treatment, making adenosine or other intravenous antiarrhythmics the preferred acute therapy. Reentrant tachycardias are the most common supraventricular tachycardia in pediatric patients, including atrioventricular reciprocating tachycardia (due to a distinct accessory pathway) and atrioventricular nodal reentrant tachycardia (due to an accessory pathway within the atrioventricular node). Patients with ventricular preexcitation, often referred to as Wolff-Parkinson-White syndrome, have a wide QRS with short PR interval, indicating antegrade conduction through the accessory pathway. These patients are at risk for sudden death if atrial fibrillation degenerates into ventricular fibrillation over a high-risk accessory pathway. Automatic tachycardias, such as atrial tachycardia and junctional ectopic tachycardia, are causes of supraventricular tachycardia in pediatric patients, the latter most typically noted after cardiac surgery. Patients with inherited arrhythmia syndromes, such as congenital long QT syndrome, are at risk of developing ventricular arrhythmias such as polymorphic ventricular tachycardia (Torsades de Pointes) which can be exacerbated by QT prolonging medications. Patients with catecholaminergic polymorphic ventricular tachycardia are at particular risk for developing bidirectional ventricular tachycardia or ventricular fibrillation during exogenous or endogenous catecholamine surges. Non-selective beta blockers are first line for most forms of long QT syndrome as well as catecholaminergic polymorphic ventricular tachycardia. Anesthesiologists should review the impact of medications on the QT interval and transmural dispersion of repolarization, to limit increasing the risk of Torsades de Pointes in patients with long QT syndrome. This review explores the key anesthetic considerations for these arrhythmias.

Influence of biliary and vascular resection types on morbidity in hepatectomies with vascular involvement.

Hepatectomies associated with vascular resections pose a technical challenge for surgeons, involving multiple reconstruction techniques. Moreover, adding clinical and surgical risks in the postoperative setting of these complex procedures are mainly due to prolonged surgical periods and potential complications inherent to vascular manipulation. Leveraging the expertise of a Cancer Center, we propose an institutional assessment utilizing the case series from A. C. Camargo Cancer Center in hepatectomies associated with vascular resection, evaluating postoperative complications and outcomes while highlighting clinical, laboratory, pathological, and surgical factors that may influence results. To assess mortality and morbidity associated with hepatectomies involving vascular resection. From a prospective database, a study was performed evaluating postoperative survival and morbidity using scoring systems such as Clavien-Dindo through a cohort analysis. From a total of 1021 liver resections for a period of 10 years, 31 cases were evaluated from a unique cancer center in Brazil! Factors such as the performance of major hepatectomies, the need for blood transfusion, and the administration of neoadjuvant or adjuvant systemic therapy did not appear to influence the outcome of morbidity or mortality. However, the resection of the associated bile duct and the type of vascular resection seemed to influence morbidity outcomes with statistical significance (p = 0.006+ …). Hepatectomies associated with vascular resections are safe in selected cases and when performed in referral centers. Factors such as associated bile duct resection and type of vascular resection should be considered for procedure indication.

#1916 Infective endocarditis in young female hemodialysis patient: a case report and literature review

Abstract Background and Aims Infective endocarditis (IE) in hemodialysis patient is one of major infective and cardiovascular complications with high morbidity and mortality. Compared to general population, incidence of IE among hemodialysis (HD) patients is 50-60 times higher. Despite the devastating implications, there is no particular preventive measures of IE for HD patients. Previous studies revealed leading risk factors for IE in HD population including use of central venous catheters (CVCs), first 6 months period of renal replacement therapy (RRT), aortic valve disease, and previous endocarditis. Case Summary We report a case of IE in a 21-year-old female hemodialysis patient using AV fistula for the past 16 months with no prior history of heart valve disease, previous endocarditis, and IV drug abuse. Patient presented with fever of 38.5°C, dyspnea, and cough since three days before admission. Physical examination revealed grade 5 pansystolic murmur with punctum maximum at apex. Vegetation on the anterior mitral leaflet (AML) was first detected through trans-thoracal echocardiography. Patient was treated with ceftriaxone and vancomycin for 14 days, followed by oral antibiotics in outpatient setting after clinical resolution. Conclusion This case provides insight of the occurrence of IE in relatively young patient in the absence of well-known risk factors, making strict prevention, prompt diagnosis and treatment are of the utmost importance. Possible pathophysiological mechanisms for IE in HD patients are bacteremia from repeated vascular manipulation and valvular calcification that compromises valve to colonization. Therefore, besides infection prevention, managing the progression of valvular calcification among HD patients remains an issue to be addressed in future studies.

Risk factors for vascular injuries in anterior lumbar interbody fusion: a single-institution retrospective study.

Vascular injuries in anterior lumbar interbody fusion (ALIF) occur due to the vascular manipulation needed to achieve optimal disc space exposure. In this study, the authors aimed to evaluate intraoperative vascular injuries in patients undergoing single- and multilevel ALIF at a large tertiary academic center. Prospectively collected data specifically addressing postoperative complications in patients who underwent ALIF by neurosurgery spine faculty working with a specialized vascular surgeon were retrospectively reviewed. Demographic characteristics and intraoperative data were collected. Patients were split into vascular injury and non-vascular injury groups. Outcome comparisons were conducted using the chi-square exact and Wilcoxon rank-sum tests for categorical and continuous data, respectively. Logistic regression was used to investigate associations with vascular injury, with univariate analysis first conducted to identify candidate associations. Based on these results, variables demonstrating a between-groups test statistic of p < 0.10 were included in the multivariate analysis to determine the independent predictors of vascular injuries. In total, 323 patients who underwent ALIF procedures were identified: 51% were male (n = 166) and 49% were female (n = 157). The mean age was 57.1 years, with 56% (n = 182) having undergone prior lumbar surgery. Vascular injuries were encountered intraoperatively in 7.1% (n = 23) of patients, and the majority (91% [n = 21]) involved the left common iliac vein. Patients with vascular injuries were statistically older (mean 63.6 vs 56.6 years), had greater incidence rates of coronary artery disease, opioid use, multilevel ALIF surgery involving the L2-3 level, and surgery involving multiple disc spaces, had more multilevel anterior instrumentation, and experienced greater blood loss during surgery and longer length of stay (all p < 0.05). Overall, there was 1 death (0.3%) secondary to aortic artery injury. Multivariate analysis identified opioid use, multilevel ALIF involving L2-3, and multiple interbodies as statistically independent predictors of vascular injury (all p < 0.05). Identifying patient risk factors can reduce the risk of vascular injuries in ALIF. Opioid use, multilevel ALIF involving L2-3, and multiple interbodies were independent predictors of vascular injuries in ALIF.

GLOVES: DOS AND DON’TS

Standard infection-prevention and control procedures must be in place during all healthcare contacts, regardless of whether a patient is known to be contagious or not, to stop the transmission of infection. As with all the items of personal protective equipment, the need for gloves must be subject to careful risk assessment of the task to be carried. Having decided that gloves should be used, a choice between sterile and non-sterile gloves must be made depending on the tasks undertaken.&#x0D; Sterile gloves are worn to prevent the transmission of microorganisms from healthcare workers (HCWs) to patients. In addition, they also protect against blood and body fluids during surgical and aseptic procedures. The recommendation to wear sterile gloves includes all surgical interventions, vaginal delivery, Insertion of indwelling devices (IV line, urinary catheter, etc.), performing lumber punctures, giving epidurals, etc., invasive radiological procedures, preparing total parenteral nutrition and chemotherapeutic agents (1). &#x0D; Non-sterile gloves are used to protect the HCWs from acquiring microorganisms from patients and contaminated environments, coming in direct contact with blood and body fluids by contact with non-intact skin or mucous membranes, e.g., vaginal examination, oral/dental care, emptying urine bags, suctioning of endotracheal tubes and by contact with the potential presence of infectious agents, e.g., MRSA both on intact and non-intact skin. Non-sterile gloves are also to be worn by contacting blood and body fluids indirectly by handling and cleaning contaminated items and equipment, handling clinical waste, and cleaning up spills of blood and body fluids (1).&#x0D; However, misuse and carelessness while wearing gloves can lead to cross-contamination, and infection spread rather than infection prevention and control. Possible microbial transmission has been documented where used gloves were not removed or changed before performing care activities requiring asepsis, not changing gloves while moving from one patient to the other, taking care of multiple patients with the same pair of gloves, wearing layers of gloves and then removing the outer layer as they move from room to room (2).&#x0D; Failure to change or remove contaminated gloves is also a significant cause of poor compliance with hand hygiene, creating a high risk of microbial transmission. Gloves are never meant to be worn in lieu of hand hygiene. Healthcare workers should wash their bare hands according to the World Health Organization's five moments of hand hygiene (3) Hand hygiene has to be followed strictly before donning and after the doffing of gloves. Gloves should only be worn in cases of the indications listed above. In some areas, HCWs are usually seen wearing gloves when there is no need. Besides contact precautions, gloves are not recommended while taking vitals, injecting intramuscularly and subcutaneously, giving oral medicines, vascular line manipulation in the absence of blood leakage, using the telephone, writing in patients’ charts, and moving patients’ furniture. Gloves should never be worn in the hallways or elevators, moving from one place to another within the hospital premises, or serving multiple patients. Gloves are not meant to be worn over and over or washed in between usage (4).&#x0D; Adhering to hand hygiene and rationalizing the use and type of gloves in any healthcare setting can help prevent microbial contamination of the environment and for the safety of patients and HCWs from microorganisms.

Arterio-venous fistula causing acute right heart failure: A rare complication of veno-arterial extracorporeal membrane oxygenation.

Introduction: Vascular complications are a major issue in V-A ECMO and can affect long term outcome. Among these, Artero-Venous (AV) fistulas may lead to right heart failure.Case History: A 73-years patient supported with V-A ECMO for post-cardiotomy biventricular failure developed right heart failure after V-A ECMO decannulation, requiring V-A ECMO recannulation. The presence of an AV femoral fistula was incidentally revealed during femoral vein cannulation, from which oxygenated blood was unexpectedly drawn. The angiographic assessment confirmed the presence of a fistula between superficial femoral artery and vein, at the site of the first venous ECMO cannulation. This was caused by the venous cannula that inadvertently passed across the artery and created an AV fistula that was opened by the venous cannula removal. The exclusion of the endovascular fistula allowed the right heart failure resolution.Conclusions: In the presence of right heart failure after recent vascular manipulation, AV fistula should be ruled out.

Renal Injuries after Cardiac Arrest: A Morphological Ultrastructural Study.

Background: This study aims to investigate the probable lesions and injuries induced in the renal tissue after a cardiac arrest. The renal ischemia–reperfusion model in cardiac arrest describes the effects of ischemia in the kidneys, alongside a whole-body ischemia–reperfusion injury. This protocol excludes ischemic conditions caused by surgical vascular manipulation, venous injury or venous congestion. Methods: For the experimental study, 24 swine were subjected to cardiac arrest. Seven minutes later, the cardiopulmonary resuscitation technique was performed for 5 min. Afterwards, advanced life support was provided. The resuscitated swine consisted one group and the non-resuscitated the other. Tissue samples were obtained from both groups for light and electron microscopy evaluation. Results: Tissue lesions were observed in the tubules, parallel to destruction of the microvilli, reduction in the basal membrane invaginations, enlarged mitochondria, cellular vacuolization, cellular apoptosis and disorganization. In addition, fusion of the podocytes, destruction of the Bowman’s capsule parietal epithelium and abnormal peripheral urinary space was observed. The damage appeared more extensive in the non-resuscitated swine group. Conclusions: Acute kidney injury is not the leading cause of death after cardiac arrest. However, evidence suggests that the kidney damage after a cardiac arrest should be highly considered in the prognosis of the patients’ health outcome.

Interpreting abdominal fluid in colic horses: Understanding and applying peritoneal fluid evidence.

Interpreting changes in peritoneal fluid helps clinicians manage colic and other diseases in horses. During abdominal problems in the horse, abdominal fluid characteristics such as color, turbidity, total nucleated and red blood cell counts, cytology, total protein, and l-lactate change in predictable ways, helping the clinician characterize the disease. Normal abdominal fluid in horses is odorless, clear to light yellow in color, and transparent. Peritoneal fluid becomes more turbid with increasing levels of protein, number of WBCs or RBCs, or with gross contamination following intestinal rupture. The color of abdominal fluid will also change with the type and quantity of cells or other elements present. The transformation of peritoneal fluid color from golden to orange to red represents increasing levels of RBCs, common with strangulating intestinal lesions. Serosanguinous defines fluid that is both turbid and orange to bloody because of increased total protein, WBCs, and RBCs, and is considered classic for diseases characterized by intestinal ischemia. Peritoneal fluid may also be red or blood-colored because of a hemoperitoneum, or secondary to blood contamination during sample collection. l-Lactate measurement in the abdominal fluid has proven invaluable for the identification of strangulating intestinal injury. Cytology acts as an important supplement to cell counts in peritoneal fluid, and the normal ratio of non-degenerate neutrophils:mononuclear cells of 2:1 changes during various gastrointestinal diseases. Culture of peritoneal fluid samples should be performed when septic peritonitis is suspected. Abdominal fluid is a sensitive indicator of intestinal injury and a useful tool to direct treatment. Peritoneal fluid evaluation includes gross visual and olfactory examination, nucleated cell count, total protein, RBC count, lactate levels, cytology, and culture. The changes noted in such variables are related to the type and duration of the abdominal problem. Abdominal fluid interpretation has become central to the triage and management of challenging equine colic patients. The transformation of peritoneal fluid color from golden to orange to red represents increasing levels of RBCs, common with strangulating intestinal lesions. Contamination with RBCs at various concentrations may be secondary to vascular (eg, abdominal wall or mesenteric vessels) or splenic trauma during abdominal fluid collection; however, this must be distinguished from orange to red fluid associated with intestinal strangulating obstruction or hemoabdomen Peritoneal fluid analysis reveals abdominal pathology by recognizing specific changes that occur with disease processes affecting the tissues and organs within this cavity. Abdominal fluid examination should be used as a tool to direct treatment rather than the definitive test for diagnosis of the acute abdomen Septic peritonitis in horses most commonly originates secondary to intestinal compromise or accidents (vascular damage, perforation, or surgical manipulation), leading to bacterial translocation into the abdomen.

Comparing the frequency of symptomatic cerebral vasospasm and vasospasm-related ischemia in Fisher 3 grade ruptured anterior communicating artery aneurysms treated via microsurgical clipping or endovascular coiling

Background and purposeIschemia due to cerebral vasospasm still remains an important cause of morbidity and mortality after aneurysmal SAH. Studies that compared the incidence of ischemia due to vasospasm between clip and coil therapies are still controversial. We compared vasospasm-induced ischemia rates between clip and coil therapies for ruptured anterior communicating artery aneurysms. Materials and methodsWe retrospectively analyzed cases of ruptured anterior communicating artery treated with clips or coils within 36 h after rupture. Patients with Glasgow Coma Scale scores < 13; Fisher grades of 1, 2, or 4; multiple aneurysms; aneurysms associated with an arteriovenous malformation; stent- or balloon-assisted coiling; and complications during or after the clipping and coiling procedure were excluded from the study. ResultsAlthough the incidence rates of ischemia and symptomatic vasospasm were higher in the coil group, no statistically significant difference was found between the two groups (P = 0.278 and P = 0.270, respectively). ConclusionWe found no significant difference in the incidence of vasospasm-induced ischemia between the patients treated with clipping and those treated with coil therapy who had Fisher grade 3 SAH and good clinical conditions. The amount of blood in basal cisterns on computed tomography, vascular manipulation, and brain retraction had the same triggering effect on vasospasm-induced ischemia.

Optical manipulation of local cerebral blood flow in the deep brain of freely moving mice.

An artificial tool for manipulating local cerebral blood flow (CBF) is necessary for understanding how CBF controls brain function. Here, we generate vascular optogenetic tools whereby smooth muscle cells and endothelial cells express optical actuators in the brain. The illumination of channelrhodopsin-2 (ChR2)-expressing mice induces a local reduction in CBF. Photoactivated adenylyl cyclase (PAC) is an optical protein that increases intracellular cyclic adenosine monophosphate (cAMP), and the illumination of PAC-expressing mice induces a local increase in CBF. We target the ventral striatum, determine the temporal kinetics of CBF change, and optimize the illumination intensity to confine the effects to the ventral striatum. We demonstrate the utility of this vascular optogenetic manipulation in freely and adaptively behaving mice and validate the task- and actuator-dependent behavioral readouts. The development of vascular optogenetic animal models will help accelerate research linking vasculature, circuits, and behavior to health and disease.

AN UNEXPECTED COMPLICATION FROM IV CONTRAST

SESSION TITLE: Medical Student/Resident Critical Care Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: The presence of gas bubbles into blood vessels can be associated with lethal consequences. Air embolism is an under-recognized complication associated with any procedure that involves vascular manipulation. Particular importance should be given to intravascular catheters insertion and intravenous contrast injections due to their frequency in every-day practice. We present a case of a pulmonary arterial embolism after a contrasted CT. CASE PRESENTATION: A 40-year-old male with a history of sigmoid diverticulitis presented to the ED complaining of sharp left lower abdominal pain. Vitals and physical examination were unremarkable except for moderate tenderness on the left lower quadrant of the abdomen. Abdominal CT scan with contrast revealed obstructing lithiasis in the distal left ureter; laboratory workup was unremarkable. Pain control was achieved and he was discharged with tamsulosin and Urology follow up. However, CT over-read disclosed gas bubbles in the main pulmonary artery, suspected to be iatrogenic from IV contrast power injection. He was prompted to return and admitted to the MICU. He denied chest pain or difficulty breathing but mentioned mild shortness of breath while the contrast was administered. EKG and chest x-ray were unremarkable. He was placed on Trendelenburg - left lateral decubitus position and supplemental oxygen was delivered through a non-rebreather mask with subsequent air resorption and no long term sequelae. DISCUSSION: Air embolism is an under-estimated risk from intravascular catheters and contrast injection. A breach in the vasculature plus a pressure gradient that favors the passage of air into the circulation allows bubbles to enter the circulation (arterial or venous). Arterial emboli causes end-organ ischemia. The air in the pulmonary microcirculation impedes blood flow and induces vasoconstriction leading to increased pulmonary arterial and right ventricular pressure. Inflammatory mediators and free radicals are released as well causing endothelial damage. Cases often present with dyspnea, chest pain, crepitus over superficial vessels, livedo reticularis; bubbles within retinal arteries are seldom seen. Diagnosis is made clinically when a patient with risk factors develops acute pulmonary, cardiovascular or neurological decompensation. Imaging tends to be normal because air is quickly absorbed. Patients are treated with repositioning (to avoid further embolization) and supplement oxygen with high FIO2 (to increase the air resorption rate). In cases of hemodynamic instability, neurologic deficits or end-organ damage: hyperbaric oxygen is indicated. CONCLUSIONS: Air embolism is a potential complication of any procedure that involves vascular intervention; keeping this in mind will help with early recognition of cases and timely therapeutic intervention. Reference #1: Jorens PG, Van Marck E, Snoeckx A, Parizel PM. Nonthrombotic pulmonary embolism. Eur Respir J. 2009;34(2):452-474. doi:10.1183/09031936.00141708 DISCLOSURES: No relevant relationships by Hung-I Liao, source=Web Response No relevant relationships by Valeria Trelles Garcia, source=Web Response No relevant relationships by Daniela Trelles Garcia, source=Web Response

Detection of flap tissue ischemia in a rat model: Real-time monitoring of changes in oxygenation and perfusion through injectable biosensors

BackgroundThe success of surgical flaps is improved by timely correction of vascular compromise. Current monitoring methods are labor or cost intensive or have limited clinical benefit. We hypothesize that injectable oxygen sensors can identify acute vascular compromise. The purpose of this study was to use a long-term, real-time method of tissue oxygenation detection in a rat flap model with vascular manipulation. MethodsSensors incorporated benzo-porphyrin dye into a microporous hydrogel and were injected intradermally 1 day before flap elevation. Inspired oxygen was modulated between 100% and 12% to confirm sensor O2 sensitivity. Eight random flaps (4 cm wide, 8 cm long) were elevated. Sensor and clinical observation to temporary clamping of the flap vascular pedicle was recorded. Sodium fluorescein in saline was injected intraperitoneally on postoperative days 0, 3, and 7 with subsequent perfusion area analysis. ResultsTissue oxygen tension measurements reflected the changes in inspired oxygen levels. Clinical observation of the flaps did not show any significant change in color or temperature with pedicle clamping. However, clamping of the pedicle resulted in a significant decrease in sensor tissue oxygen tension within 70 seconds. ConclusionOxygen monitoring of myocutaneous flaps is sensitive and can detect acute vascular occlusion. This technique is faster than current methods and offers a cost-effective and accurate means of monitoring surgical tissues.

SAT-195 The Diagnosis and Management of a Functional Paravertebral Paraganglioma

A 32-year-old male presented with a 4-year history of palpitations, diaphoresis, and orthostatic hypotension. One year prior to presentation, he began experiencing severe, episodic headaches and neck pressure. Neurological work-up included an MRI head, neck, and spine, identifying a left posterior mediastinal lesion adjacent to the T5 vertebral body, approximately 2.4 x 2.0 cm. A community surgical center attempted mass resection via Video -assisted (VATS) approach. Resection was aborted intraoperatively due to a hypertensive crisis following lesion manipulation, with his systolic blood pressure increasing above 325 mmHg.Subsequent evaluation revealed a 24-hour urine norepinephrine of 6117 nmol/d (normal <575) and normetanephrines of 16.6 umol/d (normal <3.4). An MIBG study showed intense tracer avidity in the left paraspinal lesion and minimal uptake in the adrenal glands.A functional paravertebral paraganglioma was diagnosed and the patient was initiated on alpha and beta-blockade in preparation for staged combined treatment.Spinal angiography was performed to define the arterial supply of spinal cord and tumor, which confirmed a hypervascular left thoracic paraspinal tumor. Arterial supply emanated from the left T4 intercostal and left supreme intercostal arteries and a prominent draining vein was present. Trans-arterial particle embolization was performed via both arteries with minimal residual tumor blush present post procedure.Successful VATS excision of the tumor was completed one week after arterial embolization with minimal blood loss. Pathology of the resected tumor revealed an overall intact tumor that stained diffusely positive with synaptophysin and sustentacular cells highlighted by S100 protein with a few foci of coagulative necrosis.Episodes of hypertension (maximum BP 210/80) occurred during embolization and surgical resection with vascular manipulation. These were managed with intraoperative nitroprusside and phentolamine. Peri-procedural plasma metanephrine and cathecholamine levels were collected. Normetanephrine levels (normal <=0.89 nmol/L) were 4.66 before embolization, >6.25 after embolization, 3.70 the day after embolization, 4.10 before VATS, and 0.69 after VATS. Norepinephrine levels (normal 0.8–3.4 nmol/L) were 24.3, 111.7, 61.1, 19.6, and 4 respectively. Genetic testing showed no hereditary predisposition.Discussion:Functional neuroendocrine tumours may be difficult to diagnose due to the wide variety of clinical presentations and must be considered when investigating a vascular mediastinal tumor. In our case, pre-operative embolization did not normalise plasma catecholamine levels, likely from incomplete arterial embolization, but helped reduce intra-operative surgical bleeding risk. Alpha- and beta-blockade should be continued until surgical resection, with dose adjustment as required.

Modulation of endoplasmic reticulum stress response in gut-origin encephalopathy: Impact of vascular endothelial growth factor receptor-2 manipulation

BackgroundSeptic encephalopathy, the most frequent complication of sepsis, is orchestrated by a complex interplay of signals that leads to high mortality rates among intensive care unit patients. However, the role of the vascular endothelial growth factor receptor-2 (VEGFR2) in endoplasmic reticulum stress response (ERSR), during septic encephalopathy, is still elusive. AimThis study was aimed to examine the effect of an in-house designed/synthesized VEGFR2 antagonist, named WAG4S, on septic encephalopathy using cecal ligation and perforation (CLP). Main methodsRats were intraperitoneally injected with WAG-4S (1 mg/kg/d) for 7 days post-CLP. Key findingsIn septic animals, VEGFR2 antagonism declined the expression of cortical p-VEGFR2 and p-mammalian target of rapamycin complex-1 (p-mTORC1). It also worsened the behavioral and histopathological alterations beyond CLP. However, and contrary to CLP, WAG-4S decreased the p-protein kinase R-like ER kinase (p-PERK) and eukaryotic initiation factor-2α (p-eIF2α) expression. Moreover, VEGFR2 blockade upregulated the mRNA expression of activating transcription factor-4 (ATF4), binding immunoglobulin protein/glucose-regulated protein-78 (Bip/GRP78), growth arrest and DNA damage-34 (GADD34) and spliced X-box binding protein-1 (XBP1s) above CLP. Similarly, it boosted inositol requiring enzyme-1α (IRE1α) activation and redox imbalance. In the same context, WAG-4S augmented the protein levels of CLP-induced ERSR apoptotic markers, namely C/EBP homologous protein (CHOP/GADD153), c-jun N-terminal kinase (JNK) and caspase-3. SignificanceIn conclusion, the PERK/eIF2α axis inhibition, during septic encephalopathy, is VEGFR2-independent, whereas the activated IRE1α/XBP1s/CHOP/JNK/caspase-3 cue promotes the ERSR execution module through VEGFR2 inhibition. This has turned VEGFR2 into a potential therapeutic target for ameliorating such an ailment.

2409 A Rare Complication of Gastric Bypass in the Setting of Chronic Liver Disease

INTRODUCTION: Porto-mesenteric venous thrombosis (PMVT) is a known and potentially fatal complication of general surgery. However, it has been rarely reported as a complication of worsening liver disease after undergoing bariatric surgery. This is a case of a patient who presented with mesenteric thrombosis following Roux-en-y gastric bypass (RYGB). CASE DESCRIPTION/METHODS: Patient is a 42-year-old African American female with a history of RYGB who presented with episodes of post-operative abdominal pain for 5 years. She was found to have recurrent high-grade small bowel obstruction's (SBO) necessitating a small bowel resection. Her course was further complicated by intra-abdominal abscesses requiring computed tomography (CT)-guided drainage, and wound dehiscence requiring open surgical intervention and debridement. Four months after discharge, she presented with right-sided abdominal pain and acute encephalopathy. Liver enzymes were elevated. Abdominal ultrasound revealed portal vein thrombosis (PVT). Dual-phase CT of the abdomen revealed sub-acute to chronic complete diffuse mesenteric thrombosis with collateralizations involving the portal, splenic, and distal superior mesenteric veins. Given that previous imaging suggested steatosis and hepatomegaly, sub-acute liver injury secondary to thrombosis was established in the setting of chronic liver disease. The patient's underlying non-alcoholic fatty liver disease was likely worsened by severe malnutrition and short gut syndrome following the RYGB. Her hepatic encephalopathy resolved after initiating lactulose and rifaximin. Outpatient hematology evaluation for all causes of thrombophilia remained inconclusive and the patient had no recurrences of thrombosis. DISCUSSION: RYGB remains the gold standard for bariatric surgery as it results in the most durable weight loss. However, complications may occur such as gastrointestinal leak, fistulas, marginal ulcers, SBO, and dumping syndrome. Mechanisms of thrombosis formation in this setting could be related to intra-operative vascular manipulation, increased intra-abdominal pressure, venous stasis, and possibly deteriorating liver function secondary to rapid weight loss and malnutrition. PMVT hasn't been reported consistently as a complication in various bariatric surgery studies, which leads us to conclude that it's either under or mis-diagnosed. It is extremely important to consider PMVT as a complication of RYGB in patients who have evidence of underlying liver disease prior to undergoing RYGB.

Acute Soy Supplementation Improves 20-km Time Trial Performance, Power, and Speed.

Isoflavones, a chemical class of phytoestrogens found in soybeans and soy products, may have biological functions similar to estradiol. After binding with ERβ or perhaps independently of estrogen receptors, isoflavones may augment vascular endothelial relaxation, contributing to improved limb blood flow. To determine if acute fermented soy extract supplementation influences 20-km time trial cycling performance and cardiac hemodynamics compared with a placebo. Subjects included 25 cyclists and triathletes (31 ± 8 yr, V˙O2peak: 55.1 ± 8.4 mL·kg·min). Each subject completed a V˙O2peak assessment, familiarization, and two 20-km time trials in randomized order after ingestion of a fermented soy extract supplement or placebo. The fermented soy extract consisted of 30 g powdered supplement in 16 fl. ounces of water. The placebo contained the same quantities of organic cocoa powder and water. Each trial consisted of 60 min of rest, 30 min at 55% Wpeak, and a self-paced 20-km time trial. Soy supplementation elicited a faster time to 20-km completion (-0.22 ± 0.51 min; -13 s), lower average HR (-5 ± 7 bpm), and significantly greater power (7 ± 3 W) and speed (0.42 ± 0.16 km·h) during the last 5 km of the time trial compared with placebo. Analysis of the results by relative fitness level (<57 vs ≥ 57 mL⋅kg⋅min) indicated that those with a higher level of fitness reaped the largest performance improvement alongside a reduced HR (-5 ± 7 bpm). Ingestion of a fermented soy extract supplement improved sprint-distance performance through improvements in both power and speed. For those with great aerobic fitness, soy supplementation may help to decrease cardiac demand alongside performance improvement.

A modified park bench position: the "Dormeuse" position.

Because of the restricted volume of the cisternal space, proper patient positioning on the operating table is of utmost importance during surgery by retrosigmoid approaches. Three positions are commonly used: supine, with the head rotated to the side contralateral to the lesion; the semi-sitting position; and the park bench position. Each position has advantages and disadvantages, and the surgeon should choose the one best suited to the individual patient and the pathology to be treated. We describe a modified park bench position that we call the Dormeuse position. The Dormeuse position guarantees decrease in the posterior fossa pressure and allows optimal neural and vascular manipulation and control of any aspect of the cerebellopontine angle.

Antisepsis in the handling of vascular access connections.

Needleless connectors provide easy access points to the vascular system for the administration of fluids, avoiding the risk of accidental punctures and increasing safety in vascular access manipulation. Non-aseptic manipulation can favor contamination, turning connectors into the penetration route for endoluminal contaminants with the capacity of triggering infectious complications, with serious consequences for the patient. Considering catheter-related bacteremia as a serious and avoidable adverse effect, prevention programs should incorporate measures to combat predisposing factors, such as improved staff training, the safe design of devices, improved disinfection procedures, and optimized antiseptic use. Monitoring adherence to safe practices and reporting results are important to promote understanding of the risks and benefits of decontaminating connections and thus to improve patient safety. safety. This article is part of a supplement entitled "Antisepsis in the critical patient", which is sponsored by Becton Dickinson.

F120. Intraoperative neurophysiological identification of a critical life-threatening reaction

Introduction The highest likelihood of neurologic compromise occurs during critical times of tissue and vascular structure manipulation. We report a case of neurophysiologic change after completing the critical portion of a procedure. Methods A 65 year old woman had left internal carotid artery proximal stenosis with aneurysm. She consented for endovascular therapy and listed no known drug allergies during the pre-operative process. The patient underwent successful stenting and angioplasty without complications. After completing the final post-procedure diagnostic angiogram, the anesthesiologist administered 2 grams of cefazolin just prior to closure. Within 8 min, the neuromonitoring team noted moderate global slowing on the 6-channel EEG, and a drop in the mean arterial pressure (MAP) from 70 to 24, consistent with systemic hypoperfusion. This information was conveyed to the surgeon and anesthesiologist, who were troubleshooting the arterial line under the initial assumption that the MAP decrease was technical in nature. After conferring information and confirming the lack of a palpable pulse, cardiopulmonary resuscitation was initiated with chest compressions.Given the chronology of events following administration of cefazolin and suspected anaphylactic shock, the anesthesiologist administered epinephrine (2.2 mg total) for vasoconstriction. The MAPs overshot the baseline to the 120–150 range and remained elevated for a brief period of time, but eventually returned to baseline. In addition, the anesthesiologist bolused 150 mg of propofol to decrease cerebral metabolism and lower the oxygen demand. The EEG went into near total suppression pattern but gradually returned to the intraoperative baseline over a span of thirty minutes. During this time, the catheter and guidewires were removed, and the procedure was concluded. She was noted to be moving all extremities and following commands immediately post-operation. The patient was transferred to the ICU for monitoring of clinical condition and remained intubated for 24 h for airway protection. She was extubated on post-operative day (POD) 1 and discharged at her baseline neurologic function on POD 2. Results The neuromonitoring team first identified the critical anaphylactic reaction causing systemic hypoperfusion via the neurophysiological changes and did so expeditiously resulting in cardiopulmonary resuscitation and good postoperative outcome. Conclusion This case report depicts a rare iatrogenic cause of neurologic compromise and highlights the intraoperative neuromonitoring team’s role in timely identification and resolution of complications during ”non-critical” portions of a procedure.

Microsurgical Vascular Manipulation in Aneurysm Surgery and Delayed Ischemic Injury.

The role of aggressive surgical manipulation with clot evacuation, arachnoid dissection, and papaverine-guided adventitial dissection of large vessels during ruptured aneurysm surgery in reducing vasospasm is controversial. Here we describe a single-institution experience in aneurysm surgery outcomes with and without aggressive surgery. We performed retrospective analysis of all patients >18 years of age with subarachnoid hemorrhage (SAH) from anterior circulation aneurysms between 2008 and 2013 at the University of New Mexico Hospital. Vasospasm was characterized on days 3 through 14 after SAH based on: (1) angiography, (2) vasospasm requiring angiographic intervention, (3) development of delayed ischemic neurologic deficit (DIND), and (4) radiological appearance of new strokes. Of 159 patients, 114 (71.6%) had "aggressive" and 45 (28.3%) had standard microsurgery. More than 60% of patients presented with a Hunt and Hess score of ≥3 and a Fisher grade (FG) of 4. Compared with standard surgery, there was a statistically significant decrease in the incidence of DIND in patients undergoing aggressive surgery (18.4% vs 37.8%, p=0.01). Moreover, there was a reduction in the number of new strokes by 30% in the aggressive surgery group with moderate or higher degrees of vasospasm (46.0% vs 76.5%, p=0.06). In the same group with FG 4 SAH, however, this difference was more than 50% (30% vs 64.7%, p=0.02). We conclude that aggressive surgical manipulation during aneurysm surgery results in lower incidence of DIND and new strokes. This effect is most pronounced in patients with FG 4 SAH.