Mean Arterial Pressure Research Articles

Personalized intraoperative arterial pressure management and mitochondrial oxygen tension in patients having major non-cardiac surgery: a pilot substudy of the IMPROVE trial.

The "Cellular Oxygen METabolism" (COMET) system (Photonics Healthcare, Utrecht, The Netherlands) non-invasively measures mitochondrial oxygen tension (mitoPO2) in the skin. The effects of general anesthesia and major non-cardiac surgery on mitoPO2 remain unknown. In this pre-planned pilot substudy of the "Intraoperative blood pressure Management based on the individual blood PRessure profile: impact on postOperatiVE organ function" (IMPROVE) trial, we measured mitoPO2 from induction of general anesthesia until the end of surgery in 19 major non-cardiac surgery patients (10 assigned to personalized and 9 to routine intraoperative arterial pressure management). In the overall cohort, the median (25th to 75th percentile) preoperative awake mitoPO2 was 63 (53 to 82) mmHg and mitoPO2 after induction of general anesthesia was 42 (35 to 59) mmHg. The intraoperative average mitoPO2 was 39 (30 to 50) mmHg. Thirteen patients (68%) had intraoperative mitoPO2 values below 20mmHg and the median percentage of surgical time with mitoPO2 < 20mmHg was 17 (0 to 31)%. MitoPO2 was weakly correlated with mean arterial pressure (repeated measures correlation (rrm(n); rrm(984) = 0.26, 95% confidence interval 0.20 to 0.32; P < 0.001), but not meaningfully with heart rate (rrm(984) = -0.05, 95% confidence interval -0.11 to 0.01; P = 0.117). There was no important difference in intraoperative average mitoPO2 between patients assigned to personalized or to routine intraoperativearterial pressure management (P = 0.653). MitoPO2 under general anesthesia was about a quarter lower than preoperative awake mitoPO2, substantially fluctuated during major non-cardiac surgery, and transiently decreased below 20mmHg in about two-thirds of the patients. Personalized - compared to routine - intraoperative arterial pressure management did not increase intraoperative mitoPO2. Whether intraoperative decreases in mitoPO2 are clinically meaningful warrants further investigation.

Blood pressure in human large cerebral arteries: A feasibility study.

Background: The lack of direct measures of brain blood pressure (BBP) has severely restricted understanding of cerebral pressure-flow relationships and their control. We sought to evaluate the feasibility of directly measuring BBP and its pulsatility between the aorta and middle cerebral artery (MCA) during elective endovascular surgical procedures. Methods: We report five case studies (four female, 61 ± 13 years; Mean ± SD) of patients undergoing cerebrovascular interventional procedures for aneurysm and stenoses using direct BBP measures with the COMET 2 pressure guidewire system (Boston Scientific). Patients were supine, intubated and under anesthesia. The sensor wire was inserted via the femoral artery, measuring, as feasible, BP in aorta to-MCA vascular segments, referenced to the radial artery BP waveform (arterial catheter). Results: Mean arterial pressure varied between the radial (80 ± 18 mmHg), internal carotid artery (ICA; 70 ± 25 mmHg) and MCA (62 ± 29 mmHg) and marked interindividual heterogeneity was observed. Pulse pressure was higher in the radial artery (68 ± 23 mmHg) compared to the intracranial ICA (ICAi; 43 ± 29 mmHg) and MCA (M1; 25 ± 12 mmHg) segments. Conclusions: Direct measures of BBP in humans are feasible in this interventional surgery model. Although limited by the small sample size, the results suggest a heterogenous pattern of change between systemic and brain measures of blood pressure and pulse pressure.

Effects of Gait Rehabilitation Robot Combined with Electrical Stimulation on Spinal Cord Injury Patients’ Blood Pressure

Background: Orthostatic hypotension can occur during acute spinal cord injury (SCI) and subsequently persist. We investigated whether a gait rehabilitation robot combined with functional electrical stimulation (FES) stabilizes hemodynamics during orthostatic stress in SCI. Methods: Six intermediate-phase SCI patients (five males and one female; mean age: 49.5 years; four with quadriplegia and two with paraplegia) participated. The participants underwent robotic training (RT), with a gait rehabilitation robot combined with FES, and tilt table training (TT). Hemodynamics were monitored using a laser Doppler flowmeter for the earlobe blood flow (EBF) and non-invasive blood pressure measurements. The EBF over time and the resting and exercise blood pressures were compared between each session. Adverse events were also evaluated. Results: The EBF change decreased in TT but increased in RT at the 0.5-min slope (p = 0.03). Similarly, the pulse rate change increased in TT but decreased in RT at the 1-min slope (p = 0.03). Systolic and mean blood pressures were slightly higher in RT than in TT but not significantly (p = 0.35; 0.40). No adverse events occurred in RT, but two TT sessions were incomplete due to dizziness. Conclusions: RT with FES can reduce symptoms during orthostatic stress in intermediate-phase SCI. Future studies require a larger number of cases to generalize this study.

An Easy and Quick Risk-Stratified Early Forewarning Model for Septic Shock in the Intensive Care Unit: Development, Validation, and Interpretation Study.

Septic shock (SS) is a syndrome with high mortality. Early forewarning and diagnosis of SS, which are critical in reducing mortality, are still challenging in clinical management. We propose a simple and fast risk-stratified forewarning model for SS to help physicians recognize patients in time. Moreover, further insights can be gained from the application of the model to improve our understanding of SS. A total of 5125 patients with sepsis from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database were divided into training, validation, and test sets. In addition, 2180 patients with sepsis from the eICU Collaborative Research Database (eICU) were used as an external validation set. We developed a simplified risk-stratified early forewarning model for SS based on the weight of evidence and logistic regression, which was compared with multi-feature complex models, and clinical characteristics among risk groups were evaluated. Using only vital signs and rapid arterial blood gas test features according to feature importance, we constructed the Septic Shock Risk Predictor (SORP), with an area under the curve (AUC) of 0.9458 in the test set, which is only slightly lower than that of the optimal multi-feature complex model (0.9651). A median forewarning time of 13 hours was calculated for SS patients. 4 distinct risk groups (high, medium, low, and ultralow) were identified by the SORP 6 hours before onset, and the incidence rates of SS in the 4 risk groups in the postonset interval were 88.6% (433/489), 34.5% (262/760), 2.5% (67/2707), and 0.3% (4/1301), respectively. The severity increased significantly with increasing risk in both clinical features and survival. Clustering analysis demonstrated a high similarity of pathophysiological characteristics between the high-risk patients without SS diagnosis (NS_HR) and the SS patients, while a significantly worse overall survival was shown in NS_HR patients. On further exploring the characteristics of the treatment and comorbidities of the NS_HR group, these patients demonstrated a significantly higher incidence of mean blood pressure <65 mmHg, significantly lower vasopressor use and infused volume, and more severe renal dysfunction. The above findings were further validated by multicenter eICU data. The SORP demonstrated accurate forewarning and a reliable risk stratification capability. Among patients forewarned as high risk, similar pathophysiological phenotypes and high mortality were observed in both those subsequently diagnosed as having SS and those without such a diagnosis. NS_HR patients, overlooked by the Sepsis-3 definition, may provide further insights into the pathophysiological processes of SS onset and help to complement its diagnosis and precise management. The importance of precise fluid resuscitation management in SS patients with renal dysfunction is further highlighted. For convenience, an online service for the SORP has been provided.

Evaluating the risk factors for preeclampsia in subsequent pregnancies in patients with a history of preeclampsia: a single-institution retrospective study.

A history of preeclampsia is the most important risk factor for its development in subsequent pregnancies. However, few studies have focused on the details of previous cases of preeclampsia. This single-institution, retrospective study evaluated the risk of developing preeclampsia in subsequent pregnancies in patients with a history of preeclampsia. Among singleton pregnant women who delivered at our hospital between 2017 and 2021, those who developed hypertensive disorders of pregnancy (HDP) for the first time were recruited. We retrospectively followed patients who had a subsequent pregnancy and delivery at our hospital before 2023 for a recurrence of preeclampsia. Maternal characteristics, time of HDP onset, and mean arterial pressure (MAP) during the first and early second trimester of the subsequent pregnancy were recorded. Of the 7485 deliveries, 413 were first-episode HDP cases, and the outcomes of subsequent pregnancies were noted in 48 patients with initial preeclampsia. Ten patients (21%) had a recurrence of preeclampsia, and those with early onset preeclampsia on the first pregnancy were more likely to have a recurrence (non-recurrent, 4 (11%) vs. recurrent, 5 (50%); p = 0.012). Analysis of the MAP in 40 patients showed higher recurrence rates in patients with elevations in MAP during the early second trimester (ΔMAP (early second - first trimester) median: -6 mmHg vs -3.3 mmHg, p = 0.03). Approximately 20% of patients with initial preeclampsia experience recurrence. The timing of onset in the primary pregnancy is an important predictive factor for preeclampsia in subsequent pregnancies. Changes in MAP may be useful indicators for predicting preeclampsia.

Ten-Year Evaluation of Ventilator-Associated Pneumonia (VAP) According to Initial Empiric Treatment: A Retrospective Analysis Using Real-World Data

Background/Objectives: Ventilator-associated pneumonia (VAP) is the main nosocomial infection in intensive care units (ICUs) that causes the highest morbidity and mortality. The aim of our study is to investigate variations in crude ICU mortality among patients with VAP over the past decade. We also wish to identify associated risk factors, evaluate changes in the etiology, and assess the incidence and impact of inappropriate empirical antibiotic treatment (IEAT). Methods: We conducted a retrospective, observational, single-center study over a 10-year period (2014–2024), including critically ill patients who developed VAP. The population was divided into three periods: (P1) from 2014 to 2018 (pre-COVID-19); (P2) from 2019 to 2021 (COVID-19); and (P3) from 2022 to 2024 (post-COVID-19). Binary logistic regression was used to identify which variables were independently associated with ICU mortality. Results: A total of 220 patients were included in the study (P1 = 47, P2 = 96, and P3 = 77 patients). The most prevalent microorganisms identified were P. aeruginosa, Klebsiella spp., and S. aureus. Significant variations in etiology were not observed over the years. The incidence of IEAT was 4.5%, with no observed differences between the study periods. Crude ICU mortality was 33.6%, with higher rates observed in IEAT (40% vs. 33.3%, p = 0.73). In patients with appropriate empiric antibiotic treatment (AEAT), there was a significant decrease in crude mortality over the years from 42.2% in P1 to 22.2% in P3 (p &lt; 0.001). Age (OR = 1.04; 95% CI = 1.01–1.08) and P2 (OR = 2.8; 95% CI = 1.1–7.4) were found to be independently associated with an increased risk of mortality. Conversely, a lower risk of death was associated with mean arterial pressure (OR = 0.94; 95% CI = 0.69–0.99) and the use of syndromic respiratory panel (OR = 0.23; 95% CI = 0.07–0.68). Conclusions: A reduction in crude VAP mortality over the years was observed, with no change in the etiology or rate of IEAT. The implementation of protocols using respiratory syndromic panels could be a measure to implement to reduce VAP mortality.

Safety and efficacy of low-dose esketamine weakly opioidized anesthesia in elderly patients with lumbar spinal stenosis undergoing surgery: a prospective, double-blind randomized controlled trial

BackgroundThe perioperative use of esketamine may reduce opioid use and their adverse effects. We aimed to evaluate the intraoperative safety and efficacy of weak opioidized anesthesia with low-dose esketamine in the treatment of elderly patients with lumbar spinal stenosis undergoing total laminectomy with complete decompression and interbody implant fusion.MethodsIn total, 90 elderly patients were randomized into three groups: the esketamine HS group (0.2 mg/kg induction, 0.25 mg/(kg·h) infusion), the esketamine LS group (0.2 mg/kg induction, 0.125 mg/(kg·h) infusion), and the control group (group C receiving an equal volume of saline). The primary outcome was the cumulative dose of sufentanil administered during the perioperative period. Pain (VAS rest and movement scores) on preoperative day 1 (POD-1), postoperative day 1 (POD1), postoperative day 3 (POD3), and postoperative day 7 (POD7), and serum levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), and interleukin-10 (IL-10) on POD-1, POD1, POD3, and POD7 were the secondary outcomes. We also measured mean arterial pressure and the heart rate of the three groups at each time point before anesthesia (T0), immediately after intubation (T1), 5 min after intubation (T2), at the time of surgical skin incision (T3), at the time of extubation (T4), and 30 min after surgery (T5), intraoperative propofol and remifentanil dosage, and the incidence of adverse reactions within 5 days postoperatively, etc.ResultsThe cumulative perioperative sufentanil dosage and the number of patients undergoing postoperative PACU remedial analgesia were significantly lower in the HS and LS groups compared to the C group (P < 0.05). Cumulative perioperative sufentanil use was lower in the HS group compared with the LS group (P < 0.01). The VAS dynamic and static pain scores were significantly lower in the HS group at POD1 compared to the C and LS groups. There was no significant difference in VAS dynamic and static pain scores among the three groups at POD3 and POD7 (P > 0.05). At POD1, the VAS dynamic and static pain scores were significantly lower in the HS group compared to the C and LS groups. VAS static pain scores were lower in the LS group at POD1 compared to group C (P < 0.05), whereas VAS dynamic pain scores did not differ compared to group C (P > 0.05). Compared with group C, the serum levels of TNF-α, IL-1β, and IL-6 were significantly lower in the HS and LS groups at POD1, POD3, and POD7. At POD1 and POD3, the serum levels of TNF-α, IL-1β, and IL-6 were lower in the HS group than in the LS group (P < 0.05). Serum IL-10 levels were significantly increased at POD1, POD3, and POD7 in the HS and LS groups compared with group C (P < 0.05). The incidence of intraoperative hypotension was significantly lower in the HS and LS groups compared with group C (P < 0.05). At T2 and T4, the HS and LS groups had significantly lower levels of MAP and HR decline than the C group. At T5, the MAP and HR of the C group were significantly higher than those of the HS and LS groups (P < 0.05). The HR at T3 was reduced in the LS group compared with the C and HS groups (P < 0.05). The incidence of postoperative respiratory depression was reduced in the HS and LS groups compared to the C group (P < 0.05). There was no significant difference between the three groups in terms of postoperative psychiatric adverse reactions, such as hallucinations, nightmares, diplopia, somnolence, and dizziness (P > 0.05).ConclusionLow-dose esketamine is used for its anti-inflammatory and analgesic effects in lumbar spine surgery of elderly patients. It is beneficial to hemodynamic stabilization and can reduce the incidence of postoperative respiratory depression in elderly patients. Among them, 0.2 mg/kg induction and 0.25 mg/(kg-h) infusion were more effective.Graphical

Chest Compressions Synchronized to Native Cardiac Contractions are More Effective than Unsynchronized Compressions for Improving Coronary Perfusion Pressure in a Novel Pseudo-PEA Swine Model

ABSTRACT OBJECTIVES Pulseless electrical activity (PEA) arrest, which includes pseudo-PEA, is increasingly common and survival remains dismal. We hypothesized that mechanical chest compressions synchronized to native cardiac contractions improve coronary perfusion pressure (CPP) during pseudo-PEA resuscitation. METHODS We developed a model of pseudo-PEA by infusing high dose esmolol intravenously into anaesthetized, intubated, and central arterial and venous catheterized swine to a goal of 45 mm Hg mean arterial blood pressure (MAP). We performed a randomized unblinded repeated crossover trial by administering alternating synchronized and unsynchronized chest compressions for 52 seconds preceded by 8 second breaks consecutively 4 times. We repeated the protocol approximately 4 times with 1 minute breaks. Synchronized compressions were provided 1:1 with native contractions during systole and unsynchronized compressions were provided at 100 beats per minute (BPM). We measured average CPP, MAP, and heartrate (HR) for 5 beats immediately preceding the chest compression onset and for 30 seconds 10 seconds after compression onset. We computed the difference in continuous CPP during compressions compared to the immediately preceding baseline for each interval. We developed a mixed linear model with outcome average CPP during compressions minus baseline, fixed variable compression type, and random variable animal. RESULTS We included 6 animals. Mean baseline HR was 76.0 BPM, MAP 49.9, and CPP 36.2. Chest compressions increased CPP from baseline an average 1.7 mm Hg when unsynchronized and 5.6 mm Hg synchronized. The adjusted difference was 4.0 mm Hg (95% CI 2.4–5.5). CONCLUSIONS Synchronized chest compressions increased CPP 4.0 mm Hg (135%) more than unsynchronized compressions despite a lower compression rate in medication-induced pseudo-PEA. Further refinement and eventual application to patients suffering pseudo-PEA arrest appear warranted.

Leptin receptor downregulation in the carotid body treats obesity-induced hypertension.

Obesity and co-morbid sleep disordered breathing lead to high cardiovascular morbidity and mortality via multiple mechanisms including hypertension. Obesity also leads to high levels of leptin, which is produced in adipocytes. Increased leptin levels have also been implicated in increased sympathetic activity and the pathogenesis of hypertension in obesity. However, mechanisms for the effects of leptin on blood pressure are unclear. The carotid bodies (CB) express leptin receptor (Leprb), and diet-induced obesity (DIO) increases Leprb expression levels, but the mechanisms and consequences of leptin action in CB are poorly understood. We hypothesize that leptin signaling in CB in obesity leads to hypertension, which can be treated by Leprb knockdown specifically in CB. DIO male and female mice and lean male C57BL/6J mice were implanted with telemetry in the left femoral artery for continuous blood pressure monitoring. The adenoviral vectors carrying anti-sense RNA, Ad-LepR shRNA or Ad-scrambled control shRNA, were administered locally to the CB region. Blood pressure measurements were performed at baseline and 9-11 days after CB infection with the adenoviral vector. DIO male mice showed increased blood pressure compared to lean males and DIO females. Ad-LepR shRNA induced a 2-fold decrease in Leprb mRNA level in CB and abolished obesity-induced hypertension. Leprb knockdown was particularly effective during the light phase, when animals were predominantly asleep, decreasing mean arterial pressure by 8.5 mmHg. Control shRNA had no effect on DIO-induced hypertension. We conclude that inhibition of Leprb in the carotid bodies abolished obesity-induced hypertension.

Effects of aerobic vs combined aerobic and resistance exercise training on maternal glucose metabolism, sympathetic nervous system control and cardiovascular hemodynamics in women with overweight/obesity during pregnancy.

This study aimed to identify the effects of acute aerobic exercise combined with resistance exercise on maternal glucose metabolism and sympathetic nervous system-regulated cardiovascular function in overweight or obese pregnancies. We conducted a randomized controlled trial of aerobic exercise combined with resistance training (aerobic + resistance; n = 25) compared with aerobic exercise (aerobic, n = 21) beginning at 16 wk and continuing until 36 wk of gestation in overweight or obese pregnant women. At preintervention and postintervention assessments, the glycometabolism, muscle sympathetic nervous system activity (MSNA) and cardiovascular parameters were measured and analyzed, containing fasting blood glucose (FBG), fasting blood insulin (FBI), 2 h glucose, glycosylated hemoglobin (HbA1c), homeostatic model assessment of insulin resistance (HOMA-IR), MSNA bursts/min, MSNA bursts/100 heartbeats, resting heart rate (HR); diastolic blood pressure (DBP), mean arterial pressure (MAP), systolic blood pressure (SBP), cardiac index (CI), cardiac output (CO), stroke volume (SV), total peripheral resistance (TPR) and total peripheral resistance index (TPRI). Compared to aerobic group, the overweight or obese pregnant women in aerobic + resistance group showed lower FBG, FBI, 2 h glucose, HbA1c and HOMA-IR (p < 0.05). Moreover, both MSNA bursts/min and MSNA burst/100 heartbeats level were reduced in aerobic + resistance group compared to aerobic group (p < 0.0001). Finally, the resting HR, DBP, SBP, MAP, CI, CO and TPRI were significantly decreased in aerobic + resistance group compared to aerobic group (p < 0.05). In summary, aerobic exercise combined with resistance training was associated with improved glycometabolism, MSNA and cardiovascular function in overweight or obese pregnant women compared to aerobic exercise alone.

Antihypertensive effect of sinapine extracted from rapeseed meal in 2K1C hypertensive rats

To extract sinapine from rapeseed meal and investigate its antihypertensive function and mechanism. Blood pressure was measured before and after sinapine administration to evaluate sinapine’s immediate antihypertensive function. Twokidney, oneclip (2K1C) hypertensive rats were given sinapine for four weeks, with weekly blood pressure monitoring. The renin angiotensin aldosterone system (RAAS), including the levels of renin, angiotensin I (Ang I), angiotensin II (Ang II), aldosterone (ALD), angiotensin-converting enzyme (ACE) and other molecules related to blood pressure, such as NO, prostacyclin (PGI2), endothelin-1 (ET1), and thromboxane A2 (TXA2), were measured in rat blood. The impact of sinapine on vascular endothelial cell (A10) calcium and potassium channels was assessed using the patch-clamp technique. One-time or long-term administration of sinapine significantly reduced the rats’ systolic blood pressure (SBP), diastolic pressure (DBP), and mean blood pressure (MBP). Sinapine also decreased the levels of Ang II and ALD. Furthermore, sinapine effectively inhibited ACE activation, increased NO levels, and blocked L-type calcium channels. Sinapine has an antihypertensive function and achieves this process through multiple targets.

Treatment of Restless Legs Syndrome Improves Agitation and Sleep in Persons With Dementia: A Randomized Trial.

Restless legs syndrome (RLS), a common, treatable, sensorimotor disorder of nighttime uncomfortable leg sensations that interfere with sleep, may prompt nighttime agitation in persons with dementia. This randomized trial was double-blind and placebo-controlled. Participants received a Food and Drug Administration-approved drug for RLS, gabapentin enacarbil (GEn) (Horizant) or placebo. Older adults (N= 147) with dementia due to Alzheimer's disease, nighttime agitation, and RLS, residing in long-term care or at home, participated. The primary outcome was change from baseline to 8weeks in nighttime agitation between 5 pm and 7 am on the Cohen-Mansfield Agitation Inventory Index, Direct Observation. Multivariable linear mixed effects regression models based on multiply imputed data were estimated on nighttime agitation and sleep, with treatment group, week, the 2-way interaction of group and week as predictors, and mean arterial pressure as a covariate based on baseline group imbalances. Mean age ± SD was 83.4 ± 9.1years. Most were female (72.0%), White (92.3%), non-Hispanic (84.6%), and lived in nursing homes (76.9%). Nighttime agitation, by group over time, was significant at 8weeks (estimate,-1.67; P= .003) and 2weeks. Total sleep time (actigraphy) by group over time was significant at 8weeks (estimate, 48.45; P= .026). Observed nighttime wake by group over time was significant at 2 (estimate,-12.54; P= .006) and 8weeks (estimate,-11.12; P= .015). The number having ≥1 adverse events was 60 in the GEn group (81.1%) and 50 in the placebo group (68.5%); with 12 serious adverse events in placebo and 10 in the GEn group. The GEn group had a trend toward more falls (P=.066). Our findings suggest a novel approach for nighttime agitation in persons with dementia: assessing for RLS and initiating interventions. Larger and longer trials are needed.

The Diagnostic Accuracy of Using Borderline High Office Blood Pressure Thresholds to Diagnose Masked Hypertension According to the 2017 American College of Cardiology / American Heart Association Blood Pressure Guideline.

The 2017 American College of Cardiology (ACC)/American Heart Association (AHA) BP guideline recommends ambulatory BP monitoring (ABPM) for diagnosing masked hypertension among adults not taking antihypertensive medication with borderline office BP (i.e., office systolic BP [SBP] 120 to <130 mmHg or diastolic BP [DBP] 75 to <80 mmHg). Using data from the Improving the Detection of Hypertension Study, sensitivity (SN), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), and likelihood ratios for a positive and negative test of having borderline office BP (i.e. office SBP 120 to <130 mmHg or DBP 75 to <80 mmHg) for diagnosing masked hypertension (i.e. mean awake SBP ≥130 mmHg or mean awake DBP ≥80 mmHg) were determined among 263 participants who had a mean office SBP <130 mmHg and mean DBP <80 mmHg. Likelihood ratios for a positive test >10, 5 to 10, and <5 were considered strong, moderate, and weak, respectively. Likelihood ratios for a negative test <0.1, 0.1 to 0.2, and >0.2 were considered strong, moderate, and weak, respectively. Among the 263 participants, mean±SD age was 39.2±12.8 years, 62.4% were female, 38.4% had borderline office BP, and 26.2% had masked hypertension. SN, SP, PPV, and NPV were 0.754, 0.747, 0.515, and 0.895, respectively. The likelihood ratios for a positive and negative test were 2.984 (weak) and 0.330 (weak), respectively. The use of borderline office BP thresholds recommended in the 2017 ACC/AHA BP guideline did not sufficiently rule in or rule out masked hypertension.

Agreement and Diagnostic Accuracy of New Linear Deflection Oscillometry and Doppler Devices for Hypotension Detection Compared to Invasive Blood Pressure in Anesthetized Dogs

Blood pressure (BP) monitoring is essential during anesthesia to maintain cardiovascular stability and detect hypotension. This study evaluated the agreement and diagnostic accuracy of linear deflection oscillometry (LDO) and Doppler compared to invasive blood pressure (IBP) in anesthetized dogs. Eleven healthy dogs were anesthetized, and BP measurements were taken using LDO, Doppler, and IBP methods under normotensive and hypotensive conditions. The LDO device demonstrated superior agreement, assessed using Bland–Altman analysis, with IBP, especially in hypotensive conditions, compared to the Doppler method. LDO showed bias and standard deviation in the hypotensive state, with a mean and systolic arterial pressure (MAP and SAP) of −5.1 ± 7.9 and −5.6 ± 12.5 mmHg, respectively. Conversely, Doppler measurements tended to overestimate SAP during hypotension, presenting a bias of −13 ± 15.45 mmHg. The LDO achieved an area under the curve (AUC) of 0.809 for hypotension detection, with an MAP cutoff of ≤72 mmHg (sensitivity: 90%, specificity: 63%). Meanwhile, the best threshold for Doppler measurements was an AUC of 0.798, SAP ≤ 100 mmHg (sensitivity: 77.8%, specificity: 81.8%). These results indicate that LDO is a reliable method for hypotension detection in anesthetized dogs, with potential applications for real-time monitoring. In contrast, the Doppler method may help confirm hypotension diagnoses.

Accuracy of a flash glucose monitoring system in healthy dogs during isoflurane anesthesia.

To assess the accuracy of a flash glucose monitoring system (FGMS; FreeStyle Libre 2) in healthy dogs during isoflurane general anesthesia. 6 purpose-bred Beagle dogs underwent 3 anesthetic events, 1 week apart, in a randomized crossover study. 1 of 3 mean arterial blood pressure (MAP) states were induced under isoflurane anesthesia (hypotension [MAP, ≤ 60 mm Hg], normotension [MAP, 80 to 120 mm Hg], and hypertension [MAP, ≥ 120 mm Hg]) for 40 minutes. Interstitial glucose was collected from an FGMS (applied to the dog's neck prior to anesthesia) at 0, 5, 10, 20, 30, and 40 minutes from stabilization within targeted MAP range. Whole-blood samples were collected from a lateral saphenous vein for plasma glucose measurement (blood glucose gold standard; BGGS) and via marginal lip mucosal puncture for point-of-care glucose measurement (blood glucose point-of-care; BGPOC). Shrout-Fleiss intraclass correlation and Bland-Altman analysis were performed. Accuracy was determined using human International Organization for Standardization criteria, including Parkes consensus error grid analysis. Interstitial glucose strongly correlated with BGGS and BGPOC (intraclass correlation, 0.962 and 0.953, respectively). Interstitial glucose measured higher than BGGS (median[IQR] difference 9[-2 to 20] g/dL) and lower than BGPOC (-27[-37 to -11] g/dL). Interstitial glucose BGGS increased as MAP decreased. 62.1% and 63.3% of interstitial glucose measurements were within ± 15 mg/dL when BGGS ≤ 100 mg/dL and within ± 15% of BGGS when > 100 mg/dL, respectively. However, 100% were within zones A and B of error grid analysis. Despite not meeting International Organization for Standardization standards, the FreeStyle Libre 2 demonstrated clinical accuracy for monitoring glucose concentrations in anesthetized dogs. The application of an FGMS before anesthesia may be useful for monitoring at-risk patients perioperatively.

Impact of intraoperative hypotension during laparoscopic liver resection on postoperative complications including acute kidney injury

Postoperative acute kidney injury is associated with an increase in hospital length of stay and mortality. Intraoperative hemodynamics and fluid management may contribute to acute kidney injury. The aim of this study is to evaluate the association between intraoperative duration of hypotension with adverse events after laparoscopic liver resection. A prospective cohort including adult patients undergoing laparoscopic liver resection between January 2010 and June 2022. Cumulative time below mean arterial blood pressure thresholds and association with major adverse events composing of postoperative acute kidney injury (≤2days) and complications (Dindo-Clavien ≥3a) ≤30days were assessed. In 360 patients, the median age was 61years, 206 (57%) were male, median body mass index was 26.3,and 129 (36%) patients had hepatocellular carcinoma. Acute kidney injury was recorded in 3(0.8%) patients as stage 1, 6 (1.7%) patients as stage 2, and 7 (1.9%) patients as stage 3. Major adverse events occurred in 31 (8.6%) patients, and the median estimated blood loss was 200mL. On continuous analysis, a threshold <60mmHg at ≥15minutes was found for major adverse events. The mean arterial blood pressure <55mmHg for ≥20minutes was associated with an increased risk of major adverse events (odds ratio 7.72; P < .001). In patients with >15minutes of mean arterial blood pressure <60mmHg, higher intravenous volume was associated with increase in major adverse events (P=.045), whereas adjusted intravenous volume was not associated with major adverse events (P=.657), acute kidney injury (P=.681), or blood loss (P=.875). Laparoscopic liver resection is a safe procedure with a low risk of acute kidney injury. After ≥15minutes at mean arterial blood pressure <60mmHg, the risk of major adverse events increases. Greater intravenous fluid infusion volume was associated with an observed risk for major adverse events, suggesting that mean arterial blood pressure should be managed by vasoactive agents.

Prenatal dexamethasone programs autonomic dysregulation in female rats.

Autonomic dysfunction is associated with cardiovascular and neurological diseases, including hypertension, heart failure, anxiety, and stress-related disorders. Prior studies demonstrated that late gestation exposure to dexamethasone (DEX) resulted in female-biased increases in stress-responsive mean arterial pressure (MAP) and heart rate (HR), suggesting a role for glucocorticoid-mediated programming of autonomic dysfunction. The present study investigated the influence of sympathetic (SYM) or parasympathetic (PS) blockade on cardiovascular function in male and female rat offspring of mothers injected with DEX in utero [gestation days (GD) 18-21]. At 11-12-wk of age, MAP, HR, and heart rate variability (HRV) were evaluated at baseline and in response to SYM antagonists (α1-adrenoceptor + β1-adrenoceptor), a PS (muscarinic) antagonist, or saline (SAL). To assess stress-responsive function, rats were exposed to acute restraint. Tyrosine hydroxylase was measured in the adrenals and left ventricle, and expression of the β1 adrenergic receptor, choline acetyltransferase, and acetylcholinesterase were measured in the left ventricle. Maternal DEX injection reduced basal HRV in male and female offspring. SYM blockade attenuated increases in stress-responsive HR and MAP. PS blockade elevated stress-responsive HR and MAP to a greater extent in vehicle females. SYM and PS blockade produced equivalent effects on HR and MAP responses in male offspring, regardless of maternal treatment. Based on these findings, we suggest that maternal DEX injection disrupted autonomic regulation of cardiovascular function in females, resulting in a shift toward greater SYM input and less input from PS. Future studies will investigate whether changes in autonomic function are mediated by changes in central autonomic circuitry.NEW & NOTEWORTHY Pharmacological antagonists are used to characterize the nature of the autonomic dysregulation induced in female offspring exposed to dexamethasone, in utero. The female offspring of dams injected with dexamethasone in late gestation show a reduction in vulnerability to parasympathetic blockade and an increase in responses to acute restraint stress even in the presence of sympathetic blockade. This suggests that late gestation dexamethasone disrupts the normal development of the autonomic function in females, shifting sympathovagal balance.

EFFECTS OF NORMOBARIC HYPOXIA AND HIGH-INTENSITY INTERVAL TRAINING ON HEMODYNAMICS

https://youtu.be/Jm8BVwM0X54 INTRODUCTION The purpose of this study was to evaluate the effects of high-intensity interval training (HIIT) at normobaric hypoxia (NH) on measures of hemodynamics. METHODS Ten active adults aged 23±1 years volunteered to complete a HIIT intervention at a randomized condition (sea level (SL); low NH (900m); moderate NH (2500m), high NH (4300m)) separated by 72 hours. After acclimating to the condition for 45 minutes (Rest), participants completed a HIIT intervention consisting of six bouts of high-intensity cycling separated by three minutes and 30 seconds of active recovery (AR). Hemodynamic variables included systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), pulse pressure (PP), and rate pressure product (RPP). They were assessed at Rest, during the final AR (AR6), and five minutes following the final bout of exercise (Post). A two-way repeated analysis of variance (ANOVA) was used to analyze the effects of condition (SL, 900m, 2500m, 4300m) across the repeated factor of time (Rest, AR6, Post) in response to HIIT. RESULTS There was a significant (p≤0.05) main effect of time for HR, SBP, DBP, MAP, PP, and RPP. At all conditions, HR (SL: Rest: 62±9bpm; AR6: 156±21bpm; Post: 104±15bpm; 900m: Rest: 61±10bpm; AR6: 161±10bpm; Post: 109±19bpm; 2500m: Rest: 64±11bpm; AR6: 167±14bpm; Post: 104±14bpm; 4300m: Rest: 67±14bpm; AR6: 171±11bpm; Post: 111±19bpm) increased following Rest, and AR6 was greater than Post. Additionally, at all conditions, SBP (SL: Rest: 116±7mmHg; AR6: 154±16mmHg; Post: 134±13mmHg; 900m: Rest: 119±8mmHg; AR6: 152±10mmHg; Post: 133±13mmHg; 2500m: Rest: 120±10mmHg; AR6: 153±12mmHg; Post: 136±14mmHg; 4300m: Rest: 116±10mmHg; 4300m AR6: 149±15mmHg; Post: 136±14mmHg) increased following Rest. More so, MAP at Rest was lower than AR6 and Post at SL (Rest: 66±5mmHg; AR6: 69±7mmHg; Post: 60±2mmHg) and 900m (Rest: 68±5mmHg; AR6: 70±8mmHg; Post: 68±7mmHg). At AR6, MAP was higher than Post at 900m. Similarly, PP (SL: Rest: 50±7mmHg; AR6: 85±15mmHg; Post: 64±15mmHg; 900m: Rest: 51±7mmHg; AR6: 82±10mmHg; Post: 63±11mmHg; 2500m: Rest: 48±6mmHg; AR6: 85±14mmHg; Post: 66±10mmHg; 4300m: Rest: 44±6mmHg; AR6: 77±14mmHg; Post: 63±11mmHg) was augmented following Rest at all conditions, and AR6 was higher than Post at SL, at 900m. Finally, RPP (SL: Rest: 71±13mmHg; AR6: 216±42mmHg; Post: 139±21mmHg; 900m: Rest: 73±15mmHg; AR6: 204±34mmHg; Post: 145±28mmHg; 2500m: Rest: 78±17mmHg; AR6: 202±30mmHg; Post: 141±22mmHg; 4300m: Rest: 79±21mmHg; AR6: 208±30mmHg; Post: 152±31mmHg) increased following Rest, and Post was lower than AR6, at all conditions. No other significant main effects, conditions, or interactions were observed. CONCLUSIONS While both NH and HIIT increase measures of hemodynamics, combining HIIT and NH does not further augment such variables. Thus, engaging in HIIT at NH does not increase cardiovascular stress or the risk of experiencing a cardiovascular event compared to HIIT at SL.

Effects of Remifentanil Pretreatment on Sufentanil-induced Cough Suppression During the Induction of General Anesthesia

The aim of this study was to evaluate the effect of remifentanil pretreatment on sufentanil-induced cough during general anesthesia induction. This experimental research was conducted as a single-center, randomized, parallel-group trial. A total of 120 patients scheduled for elective surgery were equally randomized into two groups (remifentanil and control). The incidence and severity of coughing in both groups were recorded after sufentanil administration during general anesthesia induction. The mean arterial pressure, heart rate, and pulse oxygen saturation were recorded at T1 (before the injection of remifentanil or normal saline), T2 (1minute after remifentanil administration), T3 (before intubation), and T4 (1minute after intubation). Additionally, the incidences of adverse events, including dizziness, nausea, apnea, truncal rigidity, bradycardia, or other adverse effects were also recorded. The incidence of sufentanil-induced cough in the remifentanil group was significantly decreased when compared with the control group (5.0% vs 35.0%, respectively; P<.001). No statistical differences were found in mean arterial pressure, heart rate, pulse oxygen saturation, and the incidences of other side effects between the two groups at T1, T2, T3, and T4 (P>.05). Pretreatment with remifentanil at a dose of 0.5mcg/kg can effectively and safely suppress the incidence and severity of sufentanil-induced coughing, providing a reference for medication during general anesthesia induction.

The hypotension prediction index in major abdominal surgery - A prospective randomised clinical trial protocol.

Patients undergoing major abdominal surgery are at increased risk of developing perioperative hypotension, which is associated with increased mortality and morbidity. Despite using advanced technologies such as evaluating arterial pressure derived cardiac output, anaesthetic management to maintain hemodynamic stability is still reactive when the clinical decision is made after hypotension has developed. Previous perioperative goal-directed studies have not proven the benefits of this approach with high certainty. A new, approved technology called the Hypotension Prediction Index (HPI) aims to prevent hypotension occurrence by allowing the precise hemodynamic monitoring of patients under general anaesthesia, significantly reducing intraoperative hypotension events. This prospective randomised clinical trial aims to compare the rate of perioperative hypotension in patients undergoing major abdominal surgery according to their type of hemodynamic monitoring. and Analysis: Patients meeting the inclusion criteria will be randomly assigned to receive hemodynamic assessment with arterial pressure cardiac output (APCO) monitoring (group A) or hemodynamic monitoring with the HPI software (group B). The primary outcome is a time-weighted average (TWA) mean arterial pressure (MAP) of <65mmHg: TWA MAP = (depth of hypotension [in mmHg] below a MAP of 65mmHg×time [in minutes] spent below a MAP of 65mmHg)/total duration of the operation (in minutes). Its secondary outcomes include perioperative hemodynamic management and the rate of postoperative complications. This trial was approved by the Ethics Committee of the Poznan University of Medical Sciences (KB-559/220; date: 01/07/2022). Its results will be submitted for publication in a peer-reviewed journal. NCT06247384.