The ATP-Binding Cassette Gene ABCF1 Functions as an E2 Ubiquitin-Conjugating Enzyme Controlling Macrophage Polarization to Dampen Lethal Septic Shock.

Sepsis is a bi-phasic inflammatory disease that threatens approximately 30 million lives and claims over 14 million annually, yet little is known regarding the molecular switches and pathways that regulate this disease. Here, we have described ABCF1, an ATP-Binding Cassette (ABC) family member protein, which possesses an E2 ubiquitin enzyme activity, through which it controls the Lipopolysaccharide (LPS)- Toll-like Receptor-4 (TLR4) mediated gram-negative insult by targeting key proteins for K63-polyubiquitination. Ubiquitination by ABCF1 shifts the inflammatory profile from an early phase MyD88-dependent to a late phase TRIF-dependent signaling pathway, thereby regulating TLR4 endocytosis and modulating macrophage polarization from M1 to M2 phase. Physiologically, ABCF1 regulates the shift from the inflammatory phase of sepsis to the endotoxin tolerance phase, and modulates cytokine storm and interferon-ß (IFN-ß)-dependent production by the immunotherapeutic mediator, SIRT1. Consequently, ABCF1 controls sepsis induced mortality by repressing hypotension-induced renal circulatory dysfunction.

Establishing targets for goal-directed anesthesia in renal transplantation: A cohort analysis of high-saliency surgical time courses.

Delayed graft function (DGF) increases morbidity and mortality in kidney transplant recipients. Operative parameters, including hemodynamic manipulation through vasopressors and fluids, can impact perfusion to the newly transplanted kidney and influence DGF incidence. We analyzed intraoperative time-series data in 5-minute intervals from kidney transplant recipient operations (N = 545) in conjunction with pretransplant characteristics and postsurgical outcomes, including DGF incidence, 60-day creatinine, and graft survival. Of the operations, 127 DGF events were captured in our cohort from a single academic transplant center (57/278 donations after brainstem death [DBDs], 65/150 donations after circulatory/cardiac death [DCDs], 5/117 live donations). In multiple regression, postanastomosis hypotension defined as mean arterial pressure (MAP) <75 mmHg was a risk factor for DGF independent of conventional predictors of DGF in DCD and DBD kidneys. DCD recipients with DGF had lower average postanastomosis MAP (DGF: 80.1 ± 8.1 mmHg vs no DGF: 76.4 ± 6.7 mmHg, P = .004). Interaction analysis demonstrated above-average doses of vasopressors and crystalloids were associated with improved outcomes when used at MAPs ≤75 mmHg, but they were associated with increased DGF at MAPs >75 mmHg, suggesting that the incidence of DGF can be highly influenced by intraoperative hemodynamic controls. This analysis of surgical time courses has identified potential new strategies for goal-directed anesthesia in renal transplantation.

Buprenorphine affects the initiation and severity of interleukin-induced acute pancreatitis in mice.

Acute pancreatitis (AP) is a common disease with no targeted therapy and has varied outcomes ranging from spontaneous resolution to being lethal. Although typically painful, AP can also be painless. Various agents, including opioids, are used for pain control in AP; the risks and benefits of which are often debated. As experimental AP in mice is used to study the efficacy of potential therapies, we studied the effect of a commonly used opioid, buprenorphine, on the initiation and progression of AP. For this, we administered extended-release buprenorphine subcutaneously before inducing the previously established severe AP model that uses interleukins 12 and 18 (IL12,18) in genetically obese (ob/ob) mice and compared this to mice with AP but without the drug. Mice were monitored over 3 days, and parameters of AP induction and progression were compared. Buprenorphine significantly reduced serum amylase, lipase, pancreatic necrosis, and AP-associated fat necrosis, which is ubiquitous in obese mice and humans. Buprenorphine delayed the AP-associated reduction of carotid artery pulse distention and the development of hypothermia, hastened renal injury, and muted the early increase in respiratory rate versus IL12,18 alone. The site of buprenorphine injection appeared erythematous, inflamed, and microscopically showed thinning, loss of epidermal layers that had increased apoptosis. In summary, subcutaneous extended-release buprenorphine interfered with the induction of AP by reducing serum amylase, lipase, pancreatic and fat necrosis, the worsening of AP by delaying hypotension, hypothermia, while hastening renal injury, respiratory depression, and causing cutaneous injury at the site of injection.NEW & NOTEWORTHY Extended-release buprenorphine interferes with the initiation and progression of acute pancreatitis at multiple levels.

Effects of aerobic exercise on ambulatory blood pressure responses to acute partial sleep deprivation: impact of chronotype and sleep quality.

Blood pressure (BP) follows a circadian rhythm intertwined with the sleep-wake cycle. Acute partial sleep deprivation (PSD; sleep ≤ 6 h) can increase BP, associated with increased cardiovascular risk. Acute exercise can reduce BP for up to 24 h, a phenomenon termed postexercise hypotension. The present study tested whether aerobic exercise could mitigate the augmented 24-h ambulatory BP caused by acute PSD. Twenty-four young otherwise healthy adults (22 ± 3 yr; 14 females; self-reported chronotypes: 6 early/10 intermediate/8 late; Pittsburgh sleep quality index: 17 good/7 poor sleepers) completed a randomized crossover trial in which, on different days, they slept normally (2300-0700), restricted sleep [0330-0700 (PSD)], and cycled for 50 min (70-80% predicted heart rate maximum) before PSD. Ambulatory BP was assessed every 30 min until 2100 the next day. Acute PSD increased 24-h systolic BP (control 117 ± 9 mmHg, PSD 122 ± 9 mmHg; P < 0.001) and prior exercise attenuated (exercise + PSD 120 ± 9 mmHg; P = 0.04 vs. PSD) but did not fully reverse this response (exercise + PSD, P = 0.02 vs. control). Subgroup analysis revealed that the 24-h systolic BP reduction following exercise was specific to late types (PSD 119 ± 7 vs. exercise + PSD 116 ± 6 mmHg; P < 0.05). Overall, habitual sleep quality was negatively correlated with the change in daytime systolic BP following PSD (r = -0.56, P < 0.01). These findings suggest that the ability of aerobic cycling exercise to counteract the hemodynamic effects of acute PSD in young adults may be dependent on chronotype and that habitual sleep quality can predict the daytime BP response to acute PSD.NEW & NOTEWORTHY We demonstrate that cycling exercise attenuates, but does not fully reverse, the augmented 24-h ambulatory blood pressure (BP) response caused by acute partial sleep deprivation (PSD). This response was primarily observed in late chronotypes. Furthermore, daytime BP after acute PSD is related to habitual sleep quality, with better sleepers being more prone to BP elevations. This suggests that habitual sleeping habits can influence BP responses to acute PSD and their interactions with prior cycling exercise.

A novel mechanism of idiopathic orthostatic hypotension and hypocatecholaminemia due to autoimmunity against aromatic l-Amino acid decarboxylase.

Orthostatic hypotension (OH) is a common condition. Many potential etiologies of OH have been identified, but in clinical practice the underlying cause of OH is often unknown. In the present study, we identified a novel and extraordinary etiology of OH. We describe a first case of acquired severe OH with syncope, and the female patient had extremely low levels of catecholamines and serotonin in plasma, urine and cerebrospinal fluid (CSF). Her clinical and biochemical evidence showed a deficiency of the enzyme aromatic l-amino acid decarboxylase (AADC), which converts l-DOPA to dopamine, and 5-hydroxytryptophan to serotonin, respectively. The consequence of pharmacologic stimulation of catecholaminergic nerves and radionuclide examination revealed her catecholaminergic nerves denervation. Moreover, we found that the patient's serum showed presence of autoantibodies against AADC, and that isolated peripheral blood mononuclear cells (PBMCs) from the patient showed cytokine-induced toxicity against AADC. These observations suggest that her autoimmunity against AADC is highly likely to cause toxicity to adrenal medulla and catecholaminergic nerves which contain AADC, resulting in hypocatecholaminemia and severe OH. Administration of vitamin B6, an essential cofactor of AADC, enhanced her residual AADC activity and drastically improved her symptoms. Our data thus provide a new insight into pathogenesis and pathophysiology of OH.

Orthostatic blood pressure changes do not influence cognitive outcomes following intensive blood pressure control.

BACKGROUND: Effects of intensive blood pressure (BP) control on cognitive outcomes in patients with excess orthostatic BP changes are unclear. We aimed to evaluate whether orthostatic BP changes modified the effects of BP intervention on cognitive impairment. METHODS: We analyzed 8547 participants from the Systolic Blood Pressure Intervention Trial Memory and cognition IN Decreased Hypertension. Associations between orthostatic BP changes and incident cognitive outcomes were evaluated by restricted cubic spline curves based on Cox models. The interactions between orthostatic BP changes and intensive BP intervention were assessed. RESULTS: The U-shaped associations were observed between baseline orthostatic systolic BP changes and cognitive outcomes. However, there were insignificant interactions between either change in orthostatic systolic BP (P for interaction = 0.81) or diastolic BP (P for interaction = 0.32) and intensive BP intervention for the composite outcome of probable dementia or mild cognitive impairment (MCI). The hazard ratio of intensive versus standard target for the composite cognitive outcome was 0.82 (95% CI 0.50-1.35) in those with an orthostatic systolic BP reduction of >20 mmHg and 0.41 (95% CI 0.21-0.80) in those with an orthostatic systolic BP increase of >20 mmHg. Results were similar for probable dementia and MCI. The annual changes in global cerebral blood flow (P for interaction = 0.86) consistently favored intensive BP treatment across orthostatic systolic BP changes. CONCLUSION: Intensive BP control did not have a deteriorating effect on cognitive outcomes among hypertensive patients experiencing significant postural BP changes.

Cardiorespiratory Instability after Percutaneous Patent Ductus Arteriosus Closure: A Multicenter Cohort Study.

OBJECTIVE: To evaluate postprocedural clinical characteristics of preterm infants undergoing transcatheter patent ductus arteriosus (PDA) closure, including oxygenation/ventilation failure and cardiovascular compromise. STUDY DESIGN: Multicenter retrospective cohort study of preterm infants who were ≤2 kg at the time of percutaneous PDA closure between August 2018 and July 2021. Indices of cardiorespiratory stability were collected pre-closure, immediately post-closure, and subsequently averaged every 4 hours for the first 24 hours post-procedure. The primary outcome was incidence of post-transcatheter cardiorespiratory syndrome: composite of hemodynamic instability (defined by systemic hypotension, systemic hypertension, or use of new inotropes/vasopressors in the first 24 hours after catheterization) and at least one of the following: (i) ventilation failure or (ii) oxygenation failure. RESULTS: A total of 197 patients were included with a median [IQR] age and weight at catheterization of 34 [25, 43] days and 1090 [900, 1367] grams, respectively. The primary composite outcome of post-transcatheter cardiorespiratory syndrome was reported in 46 (23.3%). CONCLUSION: Post-transcatheter cardiorespiratory syndrome is characterized primarily by systemic hypertension and oxygenation failure, with a very low incidence of hypotension and need for inotropes.

Prevalence of orthostatic intolerance in long covid clinic patients and healthy volunteers: A multicenter study.

Orthostatic intolerance (OI), including postural orthostatic tachycardia syndrome (PoTS) and orthostatic hypotension (OH), are often reported in long covid, but published studies are small with inconsistent results. We sought to estimate the prevalence of objective OI in patients attending long covid clinics and healthy volunteers and associations with OI symptoms and comorbidities. Participants with a diagnosis of long covid were recruited from eight UK long covid clinics, and healthy volunteers from general population. All undertook standardized National Aeronautics and Space Administration Lean Test (NLT). Participants' history of typical OI symptoms (e.g., dizziness, palpitations) before and during the NLT were recorded. Two hundred seventy-seven long covid patients and 50 frequency-matched healthy volunteers were tested. Healthy volunteers had no history of OI symptoms or symptoms during NLT or PoTS, 10% had asymptomatic OH. One hundred thirty (47%) long covid patients had previous history of OI symptoms and 144 (52%) developed symptoms during the NLT. Forty-one (15%) had an abnormal NLT, 20 (7%) met criteria for PoTS, and 21 (8%) had OH. Of patients with an abnormal NLT, 45% had no prior symptoms of OI. Relaxing the diagnostic thresholds for PoTS from two consecutive abnormal readings to one abnormal reading during the NLT, resulted in 11% of long covid participants (an additional 4%) meeting criteria for PoTS, but not in healthy volunteers. More than half of long covid patients experienced OI symptoms during NLT and more than one in 10 patients met the criteria for either PoTS or OH, half of whom did not report previous typical OI symptoms. We therefore recommend all patients attending long covid clinics are offered an NLT and appropriate management commenced.

Safety Indicators in Patients Receiving High-intensity Care After Hospital Admission for Acute Heart Failure: The STRONG-HF Trial.

BACKGROUND: Safety, Tolerability and Efficacy of Rapid Optimization, Helped by NT-proBNP Testing, of Heart Failure Therapies (STRONG-HF) demonstrated the safety and efficacy of rapid up-titration of guideline-directed medical therapy (GDMT) with high-intensity care (HIC) compared with usual care in patients hospitalized for acute heart failure (HF). In the HIC group, the following safety indicators were used to guide up-titration: estimated glomerular filtration rate of <30 mL/min/1.73 m2, serum potassium of >5.0 mmol/L, systolic blood pressure (SBP) of <95 mmHg, heart rate of <55 bpm, and N-terminal pro-B-type natriuretic peptide concentration of >10% higher than predischarge values. METHODS AND RESULTS: We examined the impact of protocol-specified safety indicators on achieved dose of GDMT and clinical outcomes. Three hundred thirteen of the 542 patients in the HIC arm (57.7%) met ≥1 safety indicator at any follow-up visit 1-6 weeks after discharge. As compared with those without, patients meeting ≥1 safety indicator had more severe HF symptoms, lower SBP, and higher heart rate at baseline and achieved a lower average percentage of GDMT optimal doses (mean difference vs the HIC arm patients not reaching any safety indicator, -11.0% [95% confidence interval [CI] -13.6 to -8.4%], P < .001). The primary end point of 180-day all-cause death or HF readmission occurred in 15.0% of patients with any safety indicator vs 14.2% of those without (adjusted hazard ratio 0.84, 95% CI 0.48-1.46, P = .540). None of each of the safety indicators, considered alone, was significantly associated with the primary end point, but an SBP of <95 mm Hg was associated with a trend toward increased 180-day all-cause mortality (adjusted hazard ratio 2.68, 95% CI 0.94-7.64, P = .065) and estimated glomerular filtration rate decreased to <30 mL/min/1.73 m2 with more HF readmissions (adjusted hazard ratio 3.60, 95% CI 1.22-10.60, P = .0203). The occurrence of a safety indicator was associated with a smaller 90-day improvement in the EURO-QoL 5-Dimension visual analog scale (adjusted mean difference -3.32 points, 95% CI -5.97 to -0.66, P = .015). CONCLUSIONS: Among patients with acute HF enrolled in STRONG-HF in the HIC arm, the occurrence of any safety indicator was associated with the administration of slightly lower GDMT doses and less improvement in quality of life, but with no significant increase in the primary outcome of 180-day HF readmission or death when appropriately addressed according to the study protocol.

In vivo cerebral metabolic and dopaminergic characteristics in multiple system atrophy with orthostatic hypotension.

PURPOSE: Multiple system atrophy (MSA) is a rare neurodegenerative disease, often presented with orthostatic hypotension (OH), which is a disabling symptom but has not been very explored. Here, we investigated MSA patients with OH by using positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG) and 11C-N-2-carbomethoxy-3-(4-fluorophenyl)-tropane (11C-CFT) for in vivo evaluation of the glucose metabolism and dopaminergic function of the brain. METHODS: Totally, 51 patients with MSA and 20 healthy controls (HC) who underwent 18F-FDG PET/CT were retrospectively enrolled, among which 24 patients also underwent 11C-CFT PET/CT. All patients were divided into MSA-OH(+) and MSA-OH(-) groups. Then, statistical parametric mapping (SPM) method was used to reveal the regional metabolic and dopaminergic characteristics of MSA-OH(+) compared with MSA-OH(-). Moreover, the metabolic networks of MSA-OH(+), MSA-OH(-) and HC groups were also constructed and analyzed based on graph theory to find possible network-level changes in MSA patients with OH. RESULTS: The SPM results showed significant hypometabolism in the pons and right cerebellar tonsil, as well as hypermetabolism in the left parahippocampal gyrus and left superior temporal gyrus in MSA-OH(+) compared with MSA-OH(-). A reduced 11C-CFT uptake in the left caudate was also shown in MSA-OH(+) compared with MSA-OH(-). In the network analysis, significantly reduced local efficiency and clustering coefficient were shown in MSA-OH(+) compared with HC, and decreased nodal centrality in the frontal gyrus was found in MSA-OH(+) compared with MSA-OH(-). CONCLUSION: In this study, the changes in glucose metabolism in the pons, right cerebellar tonsil, left parahippocampal gyrus and left superior temporal gyrus were found closely related to OH in MSA patients. And the decreased presynaptic dopaminergic function in the left caudate may contribute to OH in MSA. Taken together, this study provided in vivo pathophysiologic information on MSA with OH from neuroimaging approach, which is essential for a better understanding of MSA with OH.

Association of Diabetes with Changes in Blood Pressure during Hemodialysis: A Secondary Analysis of the Frequent Hemodialysis Network Daily Trial.

INTRODUCTION: Diabetes mellitus is a common cause of kidney failure and is often complicated by autonomic neuropathy, which may have implications for blood pressure (BP) homeostasis during hemodialysis (HD). METHODS: In this post hoc analysis of the Frequent Hemodialysis Network (FHN) Daily Trial, we used random effects Poisson and linear regression models to estimate the association of diabetes (vs. not) with intra-dialytic hypotension (IDH) and peri-dialytic BP parameters, respectively. We tested for differential associations according to the randomized treatment (6/week vs. 3/week HD) and pre-HD systolic BP. RESULTS: Of the 244 patients with intra-dialytic BP data, 100 (41%) had diabetes at baseline. The mean age was 51 ± 14 years; overall, 39% were female. In adjusted models, diabetes (vs. not) was associated with a 93% higher risk of developing IDH (IRR: 1.93; 95% CI: 1.26, 2.95). There was no evidence that the randomized treatment assignment modified the association between diabetes and IDH (pinteraction = 0.32), but more potent associations were noted among those with higher pre-HD systolic BP (pinteraction < 0.001). Diabetes (vs. not) was associated with a lower adjusted nadir intra-HD BP (-4.2; 95% CI: -8.3, -0.2 mm Hg) but not with the pre- or post-HD systolic BP. CONCLUSIONS: Among participants of the FHN Daily Trial, patients with diabetes had a higher risk of IDH and lower nadir intra-HD systolic BP than patients without diabetes, even when undergoing HD up to 6 times per week.

The Predictors and Risk Factors of 2-Year Rejection in Renal Transplant Patients: A Multicenter Case-Control Study.

INTRODUCTION: Kidney transplantation is a definitive treatment for end-stage renal disease. It is associated with improved life expectancy and quality of life. One of the most common complications following kidney transplantation is graft rejection. To our knowledge, no previous study has identified rejection risk factors in kidney transplant recipients in Saudi Arabia. Therefore, this study aimed to determine the specific risk factors of graft rejection. METHODS: A multicenter case-control study was conducted at four transplant centers in Saudi Arabia. All adult patients who underwent a renal transplant between January 1, 2015 and December 31, 2021 were screened for eligibility. Included patients were categorized into two groups (cases and control) based on the occurrence of biopsy-proven rejection within 2 years. The primary outcome was to determine the risk factors for rejection within the 2 years of transplant. Exact matching was utilized using a 1:4 ratio based on patients' age, gender, and transplant year. RESULTS: Out of 1,320 screened renal transplant recipients, 816 patients were included. The overall prevalence of 2-year rejection was 13.9%. In bivariate analysis, deceased donor status, the presence of donor-specific antibody (DSA), intraoperative hypotension, Pseudomonas aeruginosa, Candida, and any infection within 2 years were linked with an increased risk of 2-year rejection. However, in the logistic regression analysis, the presence of DSA was identified as a significant risk for 2-year rejection (adjusted OR: 2.68; 95% CI: 1.10, 6.49, p = 0.03). Furthermore, blood infection, infected with Pseudomonas aeruginosa or BK virus within 2 years of transplant, were associated with higher odds of 2-year rejection (adjusted OR: 3.10; 95% CI: 1.48, 6.48, p = 0.003, adjusted OR: 3.23; 95% CI: 0.87, 11.97, p = 0.08 and adjusted OR: 2.76; 95% CI: 0.89, 8.48, p = 0.07, respectively). CONCLUSION: Our findings emphasize the need for appropriate prevention and management of infections following kidney transplantation to avoid more serious problems, such as rejection, which could significantly raise the likelihood of allograft failure and probably death. Further studies with larger sample sizes are needed to investigate the impact of serum chloride levels prior to transplant and intraoperative hypotension on the risk of graft rejection and failure.

Neurogenic orthostatic hypotension in Parkinson's disease: is there a role for locus coeruleus magnetic resonance imaging?

Locus coeruleus (LC) is the main noradrenergic nucleus of the brain, and degenerates early in Parkinson's disease (PD). The objective of this study is to test whether degeneration of the LC is associated with orthostatic hypotension (OH) in PD. A total of 22 cognitively intact PD patients and 52 age-matched healthy volunteers underwent 3 T magnetic resonance (MRI) with neuromelanin-sensitive T1-weighted sequences (LC-MRI). For each subject, a template space-based LC-MRI was used to calculate LC signal intensity (LC contrast ratio-LCCR) and the estimated number of voxels (LCVOX) belonging to LC. Then, we compared the LC-MRI parameters in PD patients with OH (PDOH+) versus without OH (PDOH-) (matched for sex, age, and disease duration) using one-way analysis of variance followed by multiple comparison tests. We also tested for correlations between subject's LC-MRI features and orthostatic drop in systolic blood pressure (SBP). PDOH- and PDOH+ did not differ significantly (p > 0.05) based on demographics and clinical characteristics, except for blood pressure measurements and SCOPA-AUT cardiovascular domain (p < 0.05). LCCR and LCVOX measures were significantly lower in PD compared to HC, while no differences were observed between PDOH- and PDOH+. Additionally, no correlation was found between the LC-MRI parameters and the orthostatic drop in SBP or the clinical severity of autonomic symptoms (p > 0.05). Conversely, RBD symptom severity negatively correlated with several LC-MRI parameters. Our results failed to indicate a link between the LC-MRI features and the presence of OH in PD but confirmed a marked alteration of LC signal in PD patients.

ß-arrestin biased signaling is not involved in the hypotensive actions of 5-HT7 receptor stimulation: use of Serodolin.

The 5-hydroxytryptamine 7 receptor (5-HT7) is necessary for 5-HT to cause a concentration-dependent vascular relaxation and hypotension. 5-HT7 is recognized as having biased signaling, transduced through either Gs or ß -arrestin. It is unknown whether 5-HT7 signals in a biased manner to cause vasorelaxation/hypotension. We used the recently described ß-arrestin selective 5-HT7 receptor agonist serodolin to test the hypothesis that 5-HT7 activation does not cause vascular relaxation or hypotension via the ß -arrestin pathway. Isolated abdominal aorta (no functional 5-HT7) and vena cava (functional 5-HT7) from male Sprague Dawley rats were used in isometric contractility studies. Serodolin (1 nM - 10 µM) did not change baseline tone of isolated tissues and did not relax the endothelin-1 (ET-1)-contracted vena cava or aorta. In the aorta, serodolin acted as a 5-HT2A receptor antagonist, evidenced by a rightward shift in 5-HT-induced concentration response curve [pEC50 5-HT [M]: Veh = 5.2 +/- 0.15; Ser (100 nM) = 4.49 +/- 0.08; p < 0.05]. In the vena cava, serodolin acted as a 5-HT7 receptor antagonist, shifting the concentration response curve to 5-HT left and upward (%10 µM NE contraction; Veh = 3.2 +/- 1.7; Ser (10 nM) = 58 +/- 11; p < 0.05) and blocking relaxation of pre-contracted tissue to the 5-HT1A/7 agonist 5-carboxamidotryptamine. In anesthetized rats, 5-HT or serodolin was infused at 5, 25 and 75 µg/kg/min, iv. Though 5-HT caused concentration-dependent depressor responses, serodolin caused an insignificant small depressor responses at all three infusion rates. With the final dose of serodolin on board, 5-HT was unable to reduce blood pressure. Collectively the data indicate that serodolin functions as a 5-HT7 antagonist with additional 5-HT2A blocking properties. 5-HT7 activation does not cause vascular relaxation or hypotension via the ß -arrestin pathway.

Surgical closure of spinal cerebrospinal fluid leaks improves symptoms in patients with superficial siderosis.

BACKGROUND AND PURPOSE: Spinal cerebrospinal fluid (CSF) leaks may cause a myriad of symptoms, most common being orthostatic headache. In addition, ventral spinal CSF leaks are a possible etiology of superficial siderosis (SS), a rare condition characterized by hemosiderin deposits in the central nervous system (CNS). The classical presentation of SS involves ataxia, bilateral hearing loss, and myelopathy. Unfortunately, treatment options are scarce. This study was undertaken to evaluate whether microsurgical closure of CSF leaks can prevent further clinical deterioration or improve symptoms of SS. METHODS: This cohort study was conducted using data from a prospectively maintained database in two large spontaneous intracranial hypotension (SIH) referral centers in Germany and Switzerland of patients who meet the modified International Classification of Headache Disorders, 3rd edition criteria for SIH. Patients with spinal CSF leaks were screened for the presence of idiopathic infratentorial symmetric SS of the CNS. RESULTS: Twelve patients were included. The median latency between the onset of orthostatic headaches and symptoms attributed to SS was 9.5 years. After surgical closure of the underlying spinal CSF leak, symptoms attributed to SS improved in seven patients and remained stable in three. Patients who presented within 1 year after the onset of SS symptoms improved, but those who presented in 8-12 years did not improve. We could show a significant association between patients with spinal longitudinal extrathecal collections and SS. CONCLUSIONS: Long-standing untreated ventral spinal CSF leaks can lead to SS of the CNS, and microsurgical sealing of spinal CSF leaks might stop progression and improve symptoms in patients with SS in a time-dependent manner.

Effect of machine learning-guided haemodynamic optimization on postoperative free flap perfusion in reconstructive maxillofacial surgery: A study protocol.

AIMS: Intraoperative hypotension and liberal fluid haemodynamic therapy are associated with postoperative medical and surgical complications in maxillofacial free flap surgery. The novel haemodynamic parameter hypotension prediction index (HPI) has shown good performance in predicting hypotension by analysing arterial pressure waveform in various types of surgery. HPI-based haemodynamic protocols were able to reduce the duration and depth of hypotension. We will try to determine whether haemodynamic therapy based on HPI can improve postoperative flap perfusion and tissue oxygenation by improving intraoperative mean arterial pressure and reducing fluid infusion. METHODS: We present here a study protocol for a single centre, randomized, controlled trial (n = 42) in maxillofacial patients undergoing free flap surgery. Patients will be randomized into an intervention or a control group. In the intervention, group haemodynamic optimization will be guided by machine learning algorithm and functional haemodynamic parameters presented by the HemoSphere platform (Edwards Lifesciences, Irvine, CA, USA), most importantly, HPI. Tissue oxygen saturation of the free flap will be monitored noninvasively by near-infrared spectroscopy during the first 24 h postoperatively. The primary outcome will be the average value of tissue oxygen saturation in the first 24 h postoperatively.

Pilot Study to Optimize Goal-directed Hemodynamic Management During Pancreatectomy.

INTRODUCTION: Intraoperative goal-directed hemodynamic therapy (GDHT) is a cornerstone of enhanced recovery protocols. We hypothesized that use of an advanced noninvasive intraoperative hemodynamic monitoring system to guide GDHT may decrease intraoperative hypotension (IOH) and improve perfusion during pancreatic resection. METHODS: The monitor uses machine learning to produce the Hypotension Prediction Index to predict hypotensive episodes. A clinical decision-making algorithm uses the Hypotension Prediction Index and hemodynamic data to guide intraoperative fluid versus pressor management. Pre-implementation (PRE), patients were placed on the monitor and managed per usual. Post-implementation (POST), anesthesia teams were educated on the algorithm and asked to use the GDHT guidelines. Hemodynamic data points were collected every 20 s (8942 PRE and 26,638 POST measurements). We compared IOH (mean arterial pressure <65 mmHg), cardiac index >2, and stroke volume variation <12 between the two groups. RESULTS: 10 patients were in the PRE and 24 in the POST groups. In the POST group, there were fewer minimally invasive resections (4.2% versus 30.0%, P = 0.07), more pancreaticoduodenectomies (75.0% versus 20.0%, P < 0.01), and longer operative times (329.0 + 108.2 min versus 225.1 + 92.8 min, P = 0.01). After implementation, hemodynamic parameters improved. There was a 33.3% reduction in IOH (5.2% ± 0.1% versus 7.8% ± 0.3%, P < 0.01, a 31.6% increase in cardiac index >2.0 (83.7% + 0.2% versus 63.6% + 0.5%, P < 0.01), and a 37.6% increase in stroke volume variation <12 (73.2% + 0.3% versus 53.2% + 0.5%, P < 0.01). CONCLUSIONS: Advanced intraoperative hemodynamic monitoring to predict IOH combined with a clinical decision-making tree for GDHT may improve intraoperative hemodynamic parameters during pancreatectomy. This warrants further investigation in larger studies.

Hypotension in the Emergency Department and Contrast Extravasation on Computerized Tomography Predict Blood Transfusion in Low-Energy Pelvic Fractures.

INTRODUCTION: Although low-energy pelvic fractures seldom present with significant hemorrhage, early recognition of at-risk patients is essential. We aimed to identify predictors of transfusion requirements in this cohort. METHODS: A 7-y retrospective chart review was performed. Low-energy mechanism was defined as falls of ≤5 feet. Fracture pattern was classified using the Orthopedic Trauma Association/Arbeitsgemeinschaft für Osteosynthesefragen system as A, B, or C. Primary outcome was transfusion of ≥2 units of packed red blood cells in the first 48 h. Univariable analysis and logistic regression analysis were performed. A P value ≤0.05 was considered significant. RESULTS: Five hundred forty six patients were included with median (interquartile range) age of 86 (79-91) and median (interquartile range) Injury Severity Score of 5 (4-8). Five hundred forty one (99%) had type A fractures. Twenty six (5%) had the primary outcome and 17 (3%) died. Logistic regression found that systolic blood pressure <100 mmHg at any time in the Emergency Department, Injury Severity Score, and pelvic angiography were predictors of the primary outcome. Seventeen percent of those who had the primary outcome died compared with 2% who did not (P = 0.0004). Three hundred sixty four (67%) received intravenous contrast for computerized tomography scans and of these, 44 (12%) had contrast extravasation (CE). CE was associated with the primary outcome but not mortality. CONCLUSIONS: Hypotension at any time in the Emergency Department and CE on computerized tomography predicted transfusion of ≥2 units packed red blood cells in the first 48 h in patients with low-energy pelvic fractures.

Risk factors and outcomes of persistent post-transplant hypotension among simultaneous pancreas and kidney transplant recipients.

BACKGROUND: The risk factors and outcomes associated with post- transplant hypotension after simultaneous pancreas and kidney (SPK) Transplantation are poorly defined. METHODS: SPK recipients at our center between 2010 and 2021 with functioning pancreas and kidney grafts for >6 months were included. Recipients were then divided into three groups based on active medications for the treatment of hypo-or hypertension at 6-months post-transplant: those with normal blood pressure (NBP) not requiring medication (NBP group), those on antihypertensive medications (HTN group), and those on medications for hypotension (fludrocortisone and/or midodrine) (Hypotensive group). RESULTS: A total of 306 recipients were included in the study: 54 (18%) in the NBP group, 215 (70%) in the HTN group, and 37 (12%) in the Hypotensive group. On multivariate analysis, the use of T-depleting induction (aHR = 9.64, p = .0001, 95% Cl = 3.12-29.75), pre-transplant use of hypotensive medications (aHR = 4.53, p = .0003, 95% Cl = 1.98-10.38), and longer duration of dialysis (aHR = 1.02, p = .01, 95% Cl = 1.00-1.04) were associated with an increased risk of post-transplant hypotension. Post-transplant hypotension was not associated with an increased risk of death-censored kidney or pancreatic allograft failure, or patient death. CONCLUSION: Hypotension was common even 6 months post-SPK transplantation. With appropriate management, hypotension was not associated with detrimental graft or patient outcomes.

Myelography Using Energy-Integrating Detector CT Versus Photon-Counting Detector CT for Detection of CSF-Venous Fistulas in Patients With Spontaneous Intracranial Hypotension.

BACKGROUND. CSF-venous fistulas (CVFs), which are an increasingly recognized cause of spontaneous intracranial hypotension (SIH), are often diminutive in size and exceedingly difficult to detect by conventional imaging. OBJECTIVE. This purpose of this study was to compare energy-integrating detector (EID) CT myelography and photon-counting detector (PCD) CT myelography in terms of image quality and diagnostic performance for detecting CVFs in patients with SIH. METHODS. This retrospective study included 38 patients (15 men and 23 women; mean age, 55 ± 10 [SD] years) with SIH who underwent both clinically indicated EID CT myelography (slice thickness, 0.625 mm) and PCD CT myelography (slice thickness, 0.2 mm; performed in ultrahigh-resolution mode) to assess for CSF leak. Three blinded radiologists reviewed examinations in random order, assessing image noise, discernibility of spinal nerve root sleeves, and overall image quality (each assessed using a scale of 0-100, with 100 denoting highest quality) and recording locations of the CVFs. Definite CVFs were defined as CVFs described in CT myelography reports using unequivocal language and having an attenuation value greater than 70 HU. RESULTS. For all readers, PCD CT myelography, in comparison with EID CT myelography, showed higher mean image noise (reader 1: 69.9 ± 18.5 [SD] vs 37.6 ± 15.2; reader 2: 59.5 ± 8.7 vs 49.3 ± 12.7; and reader 3: 57.6 ± 13.2 vs 42.1 ± 16.6), higher mean nerve root sleeve discernibility (reader 1: 81.6 ± 21.7 [SD] vs 30.4 ± 13.6; reader 2: 83.6 ± 10 vs 70.1 ± 18.9; and reader 3: 59.6 ± 13.5 vs 50.5 ± 14.4), and higher mean overall image quality (reader 1: 83.2 ± 20.0 [SD] vs 38.1 ± 13.5; reader 2: 80.1 ± 10.1 vs 72.4 ± 19.8; and reader 3: 57.8 ± 11.2 vs 51.9 ± 13.6) (all p < .05). Eleven patients had a definite CVF. Sensitivity and specificity of EID CT myelography and PCD CT myelography for the detection of definite CVF were 45% and 96% versus 64% and 85%, respectively, for reader 1; 36% and 100% versus 55% and 96%, respectively, for reader 2; and 57% and 100% versus 55% and 93%, respectively, for reader 3. The sensitivity was significantly higher for PCD CT myelography than for EID CT myelography for reader 1 and reader 2 (both p < .05) and was not significantly different between the two techniques for reader 3 (p = .45); for all three readers, specificity was not significantly different between the two modalities (all p > .05). CONCLUSION. In comparison with EID CT myelography, PCD CT myelography yielded significantly improved image quality with significantly higher sensitivity for CVFs (for two of three readers), without significant loss of specificity. CLINICAL IMPACT. The findings support a potential role for PCD CT myelography in facilitating earlier diagnosis and targeted treatment of SIH, avoiding high morbidity during potentially prolonged diagnostic workups.