Systolic Blood Pressure Fluctuations Research Articles

O57 NOCTURNAL BLOOD PRESSURE FLUCTUATION AND DIPPING PATTERNS IN PATIENTS WITH SEVERE OBSTRUCTIVE SLEEP APNOEA

Background and Objective: Nighttime blood pressure (BP) is important for diagnosis of hypertension and for cardiovascular risk stratification. Remarkably, a reverse dipping pattern is a strong and independent predictor of overall mortality and major adverse cardiovascular events. Therefore, the further clarification of the underlying mechanisms of non- and reverse dipping is crucial to improve the treatment of patients with nighttime hypertension. Methods: We investigated 97 patients with suspected obstructive sleep apnoea (OSA, AHI >30) using standard polysomnography and continuous BP measurement based on the pulse-transit-time method (SOMNOscreen Plus®, SOMNOmedics). Frequency and amplitude of fluctuations in systolic BP following sleep disturbances (OSA) were investigated. Results: Apnoeic events went along with transient increases of BP. In some cases, systolic BP did not reach the value before the apnoea but increased over time. We defined elevations of the systolic BP baseline by >10 mmHg with a duration of >10 min as BP superpositions. The superposition periods were also characterized by increased BP amplitudes with peak values of BP up to 220 mmHg. Superposition occurred in 48 patients. Further, 65% of the OSA patients were identified as non-dippers. However, nearly all the patients with superposition (98%) were identified to have non-dipper or reverse dipper patterns. Conclusions: Our study strongly suggests that non-dipping and reverse dipping in patients with severe OSA are causally linked to OSA related BP fluctuations. Further, continuous elevations in SBP baseline (superpositions) result in extreme BP values. This behaviour with high BP peaks may be contributing to the increased mortality in patients with reverse dipping. Therefore, identification and adequate treatment of patients with reverse dipping reduces the cardiovascular risk and may prolong their life.

Intraoperative Systolic Blood Pressure as a Significant Predictor of Postoperative Hematoma Following Facelift: Single Surgeon Experience of 118 Consecutive Facelifts.

While there exists ample evidence on the impact of perioperative blood pressure on hematoma incidence following facelift; the association of elevated or labile intraoperative blood pressure with postoperative hematoma remains to be explored. The authors evaluate the association of elevated or labile intraoperative systolic blood pressure (SBP) with postoperative hematoma, using the senior author's single surgeon experience of 118 consecutive facelifts. A multivariate logistic regression was conducted using complete demographic, procedure-related, blood pressure-related, and outcomes-related data, with the outcome of interest representing postoperative hematoma. One-way ANOVA and linear regression analyses were used to assess for significant associations between a preoperative history of hypertension and a tendency to demonstrate elevated or labile intraoperative SBP. A Fisher's Exact test was subsequently used to assess for specific intraoperative SBP measurement cut-offs significantly associated with postoperative hematoma, including maximum recorded intraoperative SBP, and specific degree of intraoperative SBP fluctuations. Multivariate logistic regression demonstrated no statistically significant patient- or procedure-related demographic predictors of postoperative hematoma. With aggressive treatment of preoperative hypertension, high preoperative SBP was not found to be a significant predictor of postoperative hematoma following facelift, although this approached statistical significance (p=0.05). In contrast, labile intraoperative SBP (maximum recorded intraoperative SBP - minimum recorded intraoperative SBP; p=0.026), as well as high immediate postoperative SBP (p=0.002), were both independent and statistically significant predictors of postoperative hematoma. Patients with a preoperative history of hypertension, and more specifically those with elevated SBP measurements in the preoperative clinic, were more likely to demonstrate labile (p=0.007) or elevated (p=0.005) intraoperative SBP during facelift surgery. Specifically, maximum recorded intraoperative SBP ≥155mmHg (p=0.045), as well as maximum intraoperative SBP fluctuations ≥80mmHg (p=0.036) were found to be significantly associated with hematoma. A multimodal approach is necessary to control perioperative systolic blood pressure within the strict <120mmHg target demonstrated to significantly decrease hematoma incidence. The senior author's preference is for intraoperative SBP to remain within a strict 90-100mmHg range. In contrast to hypertension that is aggressively treated and successfully controlled, hypertension that is difficult to control intraoperatively, may be a predictor of systolic blood pressure that is difficult to control postoperatively, and thus a significant risk factor for postoperative hematoma following facelift.

Blood Pressure Fluctuation During 72 Hours After Endovascular Therapy and Prognosis in Acute Ischemic Stroke Patients.

Our study aimed to investigate the relationship between fluctuations in different blood pressure (BP) components within 72 hours following endovascular therapy (EVT) and the prognosis of acute ischemic stroke (AIS) patients. This prospective multicenter study included 283 AIS patients who underwent EVT and had available BP data. The primary outcome was the ordinal modified Rankin Scale (mRS) score evaluated at 90 days. The secondary outcome was a combination of death and major disability, defined as an mRS score of 3 to 6 within 3 months. After adjusting for imbalanced variables, the highest tertile of systolic blood pressure (SBP) fluctuation had an odds ratio (OR) of 1.747 (95% confidence interval [CI]=1.031-2.961; p for trend=0.035) for the primary outcome and 1.889 (95% CI=1.015-3.516; p for trend=0.039) for the secondary outcome, respectively. Fluctuations in diastolic blood pressure (DBP) (OR=1.914, 95% CI=1.134-3.230, p for trend=0.015) and mean arterial pressure (MAP) (OR=1.759, 95% CI=1.026-3.015, p for trend=0.039) were only associated with the primary outcome. The multivariate-adjusted restricted cubic spline analyses supported these findings. Furthermore, the fluctuations in both SBP and MAP exhibited the significant discriminatory capability in predicting the prognosis, comparable to their mean values. Our study revealed that larger fluctuations in SBP, DBP, and MAP within 72 hours after EVT were associated with a higher risk of poor clinical outcomes within 3 months in AIS patients. Controlling BP fluctuations may be valuable for improving the prognosis in patients undergoing EVT. How will this change clinical practice?It provides physicians a new approach to directly monitor BP fluctuations over an extended observation period in AIS patients after EVT in routine clinical practice.What does it mean for the clinicians?These results underscore the importance of giving equal attention to controlling long-term BP fluctuations, in addition to managing mean BP, as a means to improve the prognosis of AIS patients after EVT.What is the innovation behind the study?This study systematically evaluated the association between fluctuations in different blood pressure components and clinical outcomes in AIS patients over an extended period following EVT.

A Comparative Study Between Intravenous Esmolol and Oral Clonidine in Attenuating Hyperdynamic Cardiovascular Response to Laryngoscopy and Endotracheal Intubation.

Background In today's era of anesthesia, balanced anesthesia is the main basis of patient care and pain management. Of all the medications given during general anesthesia, premedication, induction agents, and muscle relaxants play a major role in keeping the hemodynamics properly under control. When laryngoscopy is performed to intubate, a pain stimulus will be generated, leading to a rise in blood pressure and heart rate. This stimulus can be avoided without any complications if appropriate premedication is given to the patient at the appropriate dosage. In this research, we compare the influence of injection esmolol and oral clonidine during the time of induction as premedications to suppress the hemodynamic response. Material and methods In a prospective randomized controlled trial, 90 patients were divided into three groups: Group E (esmolol) received 2 mg/kg IV esmolol diluted in 0.9% NS two minutes pre-anesthesia; Group C (clonidine) received oral clonidine 4 mcg/kg 90 minutes pre-anesthesia; and Group P (placebo) received IV normal saline and oral water. Blood pressure, heart rate, and mean arterial pressure were measured at baseline and seven subsequent time points. Results The study compared systolic blood pressure (SBP), mean arterial pressure (MAP), and diastolic blood pressure (DBP) changes over seven minutes in three groups, clonidine (Group C), placebo (Group P), and esmolol (Group E). At one minute, Group E showed a consistent MAP decrease from 95.21 mmHg to 85.92 mmHg, while Group C and Group P exhibited fluctuating trends. DBP decreased across all groups, with Group P ending highest (77.7 mmHg) and Group C lowest (66.8 mmHg). Group E's SBP decreased steadily from 126.2 mmHg to 118.0 mmHg, Group C decreased from 128 mmHg to 116.1 mmHg, and Group P showed more erratic fluctuations in SBP, DBP, and MAP. Conclusion These findings suggest that intravenous esmolol shows a good hemodynamic response having superior control over heart rate and getting the pressure under control quickly without major drop compared with the clonidine and placebo groups.

NOCTURNAL BLOOD PRESSURE FLUCTUATIONS IN PATIENTS WITH OBSTRUCTIVE SLEEP APNEA

Objective: Reverse dipping of nocturnal blood pressure (BP) is a sensitive predictor of cardiovascular morbidity and mortality. Nocturnal blood pressure fluctuations (NBPF) related to obstructive sleep apnea may be causative. Studies based on ambulatory blood pressure measurements (ABPM) can only provide mean BP values and long-term BP variability due to low frequent variability during the night. This limits the explanatory power of the method. Here, we apply non-invasive, continuously measuring methods to investigate NBPF in patients with obstructive sleep apnea syndrome (OSAS). Design and method: In a first study, we included 34 patients with suspected diagnosis of sleep apnea undergoing polysomnography. BP was estimated using pulse transit time (PTT, SOMNOscreenTM) as well as measured by Portapres®. In a second study, we included 97 patients with an apnea/hypopnea index greater than 30 (severe OSA). The systolic BP (SBP) was continuously determined using PTT (SOMNOscreenTM) during polysomnography. Results: In the first study, 11 patients with OSA were analyzed. Sleep apnea related SBP fluctuations &gt;8mmHg measured by Portapres™ were included. Both, the PTT-based method and Portapres® detected the same apnea related SBP fluctuations during night. Bland Altman plot showed a mean difference &lt;1mmHg between both methods, with limits of agreement of ±13.4 mmHg. Mean apnea related SBP fluctuations were between 28 and 29 mmHg for both methods. In the second study, we found, in addition to normal NBPFs, BP fluctuations arranged like steps in 48 patients. Thereby, the SBP decrease after the event did not reach the level before the apnea. This led to a continuous increase of the SBP baseline called “superposition” of BP. Further, this phenomenon resulted in extremely high SBP values in some of the patients. Conclusions: BP fluctuations induced by OSA may contribute to the non-dipping/reverse dipping phenomena in OSA patients. The continuously measuring methods used here offer detailed insight into patterns of BP fluctuations. This improves our understanding of BP control during night time and helps to identify patients with increased risk for cardiovascular events.

Assessment of Blood Pressure and Heart Rate Related Variables in Acute Stroke Patients Receiving Intravenous Antihypertensive Medication Infusions.

We performed an analysis of a large intensive care unit electronic database to provide preliminary estimates of various blood pressure parameters in patients with acute stroke receiving intravenous (IV) antihypertensive medication and determine the relationship with in-hospital outcomes. We identified the relationship between pre-treatment and post-treatment systolic blood pressure (SBP) and heart rate (HR)-related variables and in-hospital mortality and acute kidney injury in patients with acute stroke receiving IV clevidipine, nicardipine, or nitroprusside using data provided in the Medical Information Mart for Intensive Care (MIMIC) IV database. A total of 1830 patients were treated with IV clevidipine (n = 64), nicardipine (n = 1623), or nitroprusside (n = 143). The standard deviations [SDs] of pre-treatment SBP (16.3 vs. 13.7, p ≤ 0.001) and post-treatment SBP (15.4 vs. 14.4, p = 0.004) were higher in patients who died compared with those who survived, particularly in patients with intracerebral hemorrhage (ICH). The mean SBP was significantly lower post treatment compared with pre-treatment values for clevidipine (130.7mm Hg vs. 142.5mm Hg, p = 0.006), nicardipine (132.8mm Hg vs. 141.6mm Hg, p ≤ 0.001), and nitroprusside (126.2mm Hg vs. 139.6mm Hg, p ≤ 0.001). There were no differences in mean SDs post treatment compared with pre-treatment values for clevidipine (14.5 vs. 13.5, p = 0.407), nicardipine (14.2 vs. 14.6, p = 0.142), and nitroprusside (14.8 vs. 14.8, p = 0.997). The SDs of pre-treatment and post-treatment SBP were not significantly different in patients with ischemic stroke treated with IV clevidipine, nicardipine, or nitroprusside or for patients with ICH treated with IV clevidipine or nitroprusside. However, patients with ICH treated with IV nicardipine had a significantly higher SD of post-treatment SBP (13.1 vs. 14.2, p = 0.0032). We found that SBP fluctuations were associated with in-hospital mortality in patients with acute stroke. IV antihypertensive medication reduced SBP but did not reduce SBP fluctuations in this observational study. Our results highlight the need for optimizing therapeutic interventions to reduce SBP fluctuations in patients with acute stroke.

Blood Pressure Fluctuation Pattern Associated with 90-Day Ischemic Stroke and Transient Ischemic Attack After Total Knee Arthroplasty-A Retrospective Study.

Blood pressure (BP) fluctuation has been demonstrated to be closely associated with stroke. However, at present, no attention is paid to the BP fluctuation following total knee arthroplasty (TKA). The aim of this study is to investigate what is BP fluctuation patterns in stroke and transient ischemic attack (TIA) patients after primary TKA, compare clinical characteristics among different BP fluctuation patterns and determine whether it could predict the occurrence of a 90-day stroke. A retrospective study was conducted from February 1, 2011 to February 15, 2021. Stroke or TIA patients within 90 days after TKA were included. Data from a hospitalization management system were analyzed, including demographics, smoking status, comorbidities, medications, surgical variables, and 90-day stroke, mortality, and readmission rates. BP fluctuation patterns were defined based on the average BP in the first 3 days after TKA. A logistic regression analysis model was used to identify risk factors for 90-day stroke or TIA following TKA. Of the 1687 patients who underwent primary TKA, 4.0% (68/1687) experienced a 90-day stroke or TIA. A total of 63 patients met the inclusion criteria, with an average age of 67.5 years and 55.6% (35/63) female. The number of stroke or TIA patients in each BP fluctuation pattern (T1-T5) was 6 (9.5%), 5 (7.9%), 4 (6.3%), 13 (20.6%), and 35 (55.6%) respectively. Patients with a T5 pattern tended to be older and had a greater reduction in average systolic blood pressure (SBP) 3 days after surgery compared to other patterns. The T5 pattern was associated with a higher occurrence of stroke and a lower occurrence of TIA. Patients with a T5 pattern also had a longer length of stay within 90 days following TKA. After adjusting for confounding factors, average SBP fluctuation ≥40 mmHg and the T5 pattern of BP fluctuation remained risk factors for 90-day stroke or TIA after TKA. BP fluctuation patterns in the early postoperative period are associated with 90-day stroke and TIA following primary TKA.

Systolic blood pressure time in target range and long-term outcomes in patients with ischemic cardiomyopathy

The relationship between the degree of systolic blood pressure (SBP) control and outcomes remains unclear in patients with ischemic cardiomyopathy (ICM). Current control metrics may not take into account the potential effects of SBP fluctuations over time on patients. This study was a post-hoc analysis of the surgical treatment of ischemic heart failure trial which enrolled 2,136 participants with ICM. Our SBP target range was defined as 110 to 130 mm Hg and the time in target range (TTR) was calculated by linear interpolation. A total of 1,194 patients were included. Compared with the quartile 4 group (TTR 77.87%-100%), the adjusted hazard ratios and 95% confidence intervals of all-cause mortality were 1.32 (0.98-1.78) for quartile 3 group (TTR 54.81%-77.63%), 1.40 (1.03-1.90) for quartile 2 group (TTR 32.59%-54.67%), and 1.53 (1.14-2.04) for quartile 1 group (TTR 0%-32.56%). Per 29.28% (1-SD) decrement in TTR significantly increased the risk of all-cause mortality (1.15 [1.04-1.26]). Similar results were observed in the cardiovascular (CV) mortality and the composite outcome of all-cause mortality plus CV rehospitalization, and in the subgroup analyses of either coronary artery bypass grafting or medical therapy, and different baseline SBP. In patients with ICM, the higher TTR was significantly associated with decreased risk of all-cause mortality, CV mortality and the composite outcome of all-cause mortality plus CV rehospitalization, regardless of whether the patient received coronary artery bypass grafting or medical therapy, and the level of baseline SBP. TTR may be a surrogate metric of long-term SBP control in patients with ICM.

A novel murine model of autoimmune dysautonomia by α3 nicotinic acetylcholine receptor immunization.

We aimed to establish a novel murine model of autoimmune autonomic ganglionopathy (AAG), which represents autoimmune dysautonomia, associated with MHC class II to understand its pathomechanism and the pathogenicity of nicotinic acetylcholine receptor (nAChR) antibodies. The amino acid sequence of the mouse nAChRα3 protein was analyzed using an epitope prediction tool to predict the possible MHC class II binding mouse nAChRα3 peptides. We focused on two nAChRα3 peptides in the extracellular region, and experimental AAG (EAAG) was induced by immunization of C57BL/6 mice with these two different peptides. EAAG mice were examined both physiologically and histologically. Mice with EAAG generated nAChRα3 antibodies and exhibited autonomic dysfunction, including reduced heart rate, excessive fluctuations in systolic blood pressure, and intestinal transit slowing. Additionally, we observed skin lesions, such as alopecia and skin ulcers, in immunized mice. Neuronal cell density in the sympathetic cervical ganglia in immunized mice was significantly lower than that in control mice at the light microscopic level. We interpreted that active immunization of mice with nAChRα3 peptides causes autonomic dysfunction similar to human AAG induced by an antibody-mediated mechanism. We suggested a mechanism by which different HLA class II molecules might preferentially affect the nAChR-specific immune response, thus controlling diversification of the autoantibody response. Our novel murine model mimics AAG in humans and provides a useful tool to investigate its pathomechanism.

The effect of intravenous lidocaine on propofol dosage in painless bronchoscopy of patients with COPD.

BackgroundWe tested the hypothesis that intravenous (IV) lidocaine reduces propofol requirements in painless bronchoscopy in patients with chronic obstructive pulmonary disease (COPD).MethodsA total of 93 patients who underwent bronchoscopy were included in this randomized placebo-controlled study. The patients were randomly divided into two groups. After the IV doses of nalbuphine, patients were given a bolus of propofol, which was titrated if necessary until loss of consciousness. Then patients were given IV lidocaine (2 mg/kg then 4 mg/kg/h) or the same volume of saline. The primary endpoint was the propofol requirements. Secondary endpoints were the incidence of hypoxemia, the incidence of cough during glottis examination, the systolic blood pressure (SBP) and heart rate (HR) during bronchoscopy procedures, the bronchoscopist's comforts, and the time for wakefulness before recovery.ResultsLidocaine infusion resulted in a significant reduction in propofol requirements (p < .0001), and the incidence of hypoxemia (p = .001) and cough (p = .003) during examination decreased significantly in the lidocaine group. During the examination, the fluctuation of SBP and HR was significantly lower than that in the control group, and the difference was statistically significant (p < .05). Bronchoscopist's comforts were higher in the lidocaine group (p < .001), and time for wakefulness (p < .001) were significantly lower in the lidocaine group.ConclusionIn painless bronchoscopy in patients with COPD, IV infusion of lidocaine resulted in a reduction in propofol dose requirements and reduce the incidence of adverse events.

Surgical treatment of large pheochromocytoma (>6 cm): A 10-year single-center experience

ObjectiveClinical practice guidelines recommend open adrenalectomy (OA) for large pheochromocytoma (LPCC) > 6 cm in size. Although laparoscopic adrenalectomy (LA) for the treatment of LPCC has been reported, its role remains unclear. This study aimed to compare the effectiveness of LA and OA, and summary the surgical treatment experience. MethodsData concerning LPCC, from January 2010 to June 2019 of a single institution, were retrospectively reviewed. Altogether 82 patients with a tumor larger than 6 cm were included (52 patients in LA group and 30 patients in OA group). Groups were balanced by propensity score matching (PSM) into 15 pairs. Patients’ demographics, preoperative characteristics, and prognosis were analyzed. ResultsBefore PSM, the OA group had larger tumor sizes (median [interquartile range, IQR]: 8.9 [7.3–10.3] vs. 7.2 [6.7–8.0] cm; p=0.000) and higher vanillylmandelic acid level (median [IQR]: 114.3 [67.8–326.4] vs. 66.6 [37.8–145.8] μmol/24 h; p =0.004) and needed a higher cumulative dose of prazosin (median [IQR]: 83.5 [37.0–154.0] vs. 38.0 [21.0–81.0] mg; p=0.028). After PSM, the baseline data showed no significant differences between both groups. The LA group had relatively more stable blood pressure in surgery, with a lower fluctuation of systolic blood pressure (mean±standard deviation [SD]: 70.9±25.1 vs. 107.4±46.2 mmHg, p=0.012) and a lower percentage of hemodynamic instability (46.7% vs. 86.7%, p=0.020). The LA group had shorter postoperative hospital stays (mean±SD: 6.4±2.7 vs. 10.1±3.4 days; p=0.003) than the OA group. Differences regarding metastasis rate (6.7% vs. 0, p=1.000) were not statistically significant between LA and OA groups. The median (IQR) follow-up time of 82 patients was 72.5 (47.0–103.5) months. Binary logistic regression showed that right-side tumors or those >8 cm in size were independent risk factors of OA. ConclusionLA is a safe, minimally invasive procedure for LPCC and has relatively better perioperative characteristics in large medical centers. Patients with tumors on the right side or larger than 8 cm are more likely to undergo OA initially.

Factors Associated With Differences in the Initial Location of Structural Progression in Normal-Tension Glaucoma.

Précis:Different clinical factors are associated with the location of the first structural progression in glaucoma.Purpose:The aim was to investigate the underlying clinical parameters affecting the location of the initial structural progression of glaucoma in patients with normal-tension glaucoma (NTG).Methods:This retrospective study included 228 eyes of 228 patients with NTG. In total, 130 eyes of 130 patients demonstrated structural progression (as determined by event-based guided progression analysis using Cirrus HD-optical coherence tomography) in the peripapillary retinal nerve fiber layer (ppRNFL) or macular ganglion cell inner plexiform layer (mGCIPL). Depending on where the progression occurred first, it was defined as either ppRNFL first progression or mGCIPL first progression. Clinical parameters associated with each first progression were identified using logistic regression.Results:In total, 50 eyes showed ppRNFL first progression and 64 eyes showed mGCIPL first progression. ppRNFL first progression was significantly associated with female sex [odds ratio (OR)=5.705, P=0.015], lack of systemic hypertension (OR=0.199, P=0.014), disc hemorrhage (OR=4.188, P=0.029), higher mean intraocular pressure (OR=1.300, P=0.03), and lower pattern SD (OR=0.784, P=0.028). In contrast, male sex (OR=0.450, P=0.043), lower central corneal thickness (OR=0.987, P=0.032), higher intraocular pressure fluctuation (OR=1.753, P=0.047), lower systolic blood pressure fluctuation (OR=0.839, P=0.002), and higher diastolic blood pressure fluctuation (OR=1.208, P=0.015) were significantly associated with mGCIPL first progression.Conclusions:Different clinical factors were associated with the initial site of structural glaucoma progression in patients with NTG depending on its peripapillary or macular location, and these findings suggest possible differences in underlying mechanisms of glaucoma damage.

Nocturnal Blood Pressure Fluctuations in Patients with Rapid Eye Movement-Related Obstructive Sleep Apnea.

Rapid eye movement-related obstructive sleep apnea (REM-related OSA) is a polysomnographic phenotype. Nocturnal blood pressure (BP) fluctuations remain unclear in patients with REM-related OSA. We studied 27 patients with REM-related OSA, categorized as having REM-apnea-hypopnea index (REM-AHI) ≥ 5/h, REM-AHI/non-REM-AHI ≥ 2, and non-REM-AHI < 15/h. Beat-to-beat systolic BP (SBP) variability and nocturnal SBP fluctuation patterns using pulse transit time (PTT) were investigated. The maximum increase and average nocturnal SBP were significantly higher in males than in females (p = 0.003 and p = 0.008, respectively). The rate of non-dipping patterns in nocturnal SBP fluctuations was 63% in all patients (males, 70%; females, 50%). Epworth Sleepiness Scale (ESS) and Self-rating Depression Scale (SDS) scores in females were higher than those in males (8.4 ± 6.1 vs. 13.4 ± 5.4 points, p = 0.04; 43.8 ± 7.9 vs. 52 ± 11.6 points, p = 0.04, respectively). A high proportion of patients with REM-related OSA had a non-dipping pattern. Using PPT, we observed that in patients with REM-related OSA, SBP variability was greater in males. Despite clinical symptoms being slightly more severe in females, nocturnal SBP fluctuations should be considered in male patients with REM-related OSA.

Microcirculatory bed in reperfused flaps: modern possibilities for the correction of hemodynamic disorders (part III)

The paper presents an analysis of the literature data concerning the autoregulation of tissue blood flow in free axial flaps. Autoregulation of microcirculation is an extremely important physiological phenomenon that ensures the stability of peripheral blood circulation and adequate metabolism in organs and tissues, regardless of fluctuations in systolic blood pressure in the range of 80-160 mm Hg. The types of sludge and their origin are described. Technologies of elimination of erythrocyte aggregates (sludge) by using dextrans of different molecular weights and pentoxifylline are discussed. Controlling the duration of primary ischemia, maintaining adequate perfusion pressure in the replants of the limbs and in free flaps, as well as reducing the peripheral vascular resistance in them, will make it possible to level the disturbances in the autoregulation of microcirculation in the reperfused tissues, ensuring the stability of capillary pressure.

Pathogenetic Development Factors of Position-dependent Changes in Oxygen Saturation

It is known that the oxygen saturation of the peripheral blood is determined by the efficiency of the heart, the state of the microcirculatorybed, so position-dependent fluctuations in systolic blood pressure, pressure in the left renal and left adrenal veins,mediated bursts of hormones of the adrenal cortex can affect SO2. There is every reason to believe that SO2 will change in differentstatic positions. Aim. To study position-dependent changes in oxygen saturation based on the study of the pathogenetic effect of venous bloodflow in the “pool” of the left renal vein on the general hemodynamics and hormones of the adrenal cortex. Material and methods. A method for the polypositional assessment of oxygen saturation disturbances in six static states has beendeveloped: standing, sitting, on the back, on the abdomen, on your right side, on your left side. Statistical data processing was carriedout, which made it possible to determine the relationship between the indicators. Results. Polypositional studies of oxygen saturation hemodynamic parameters (SрO2) in six static states revealed the variability ofthe relationships of these groups when comparing them. The correlation was high, statistically significant between diastolic (DBP)and systolic (SBP) pressure, moderate between pulse (Ps) and SBP, pulse and DBP, weak between pulse and saturation. The groupsdivided by body positions relative to the pulse, SBP and DBP did not have a cluster structure. In the pron-position, SO2 had a minimalvalue, significantly different from the data in the other positions. Conclusion. Body position is one of the pathogenetically significant factors regulating blood oxygen saturation, which can helpin the treatment and rehabilitation of patients with respiratory failure (COVID-19). Polypositional saturation measurement in sixstatic states can determine a new, more effective algorithm for the management of patients with respiratory failure, both duringtreatment and during rehabilitation.

Fetal cardiac intervention and perioperative management of fetus with hypoplastic right heart syndrome

Objective: To summarize the experience of perioperative management strategy of fetal pulmonary valvuloplasty (FPV) for hypoplastic right heart syndrome (HRHS). Methods: In the retrospective study of perioperative data, 13 fetuses of HRHS were treated with FPV in Qingdao Women and Children's Hospital from July 2018 to June 2019. Results: (1) The evaluation indexes of the right ventricle in 13 fetuses before FPV: the mean ratio of tricuspid/mitral annulus, right/left ventricular length, pulmonary/aortic annulus, and tricuspid inflow time/cardiac cycle were 0.81±0.04, 0.56±0.14, 0.69±0.06, and 0.35±0.03, respectively. (2) All pregnant mothers underwent general anesthesia. The basic fetal heart rate was (156±12) beats per minutes before FPV, and 9 fetuses showed bradycardia during the operation, and recovered to normal after drug resuscitation. On the first day after FPV, two cases had bradycardia and pregnancy was terminated. The fluctuation of systolic blood pressure of pregnant mother was less than 20%, and there was no significant difference between preoperative and intraoperative pulse pressure [(36.0±5.6) vs (35.8±6.9) mmHg (1 mmHg=0.133 kPa); t=8.102, P=0.951]. (3) All cases of HRHS fetus successfully underwent FPV. The average gestational age was (27.3±0.8) weeks. The average operation time was (23.2±1.0) minutes. The ratio of tricuspid to mitral annulus (t=-2.513, P=0.022) and the ratio of right to left ventricular length (t=-3.373, P=0.003) were significantly improved at 6 weeks postoperatively. Ten fetuses were delivered, and there was no death after early intervention. (4) Of 13 pregnant women, 3 cases were nausea and vomiting on the day of FPV operation, the treatment of the symptoms was improved by tropisetron; one case had tolerable abdominal pain and improved without special treatment. Pregnant women had no major complications such as cardiac failure, abortion and death. (5) Chromosome karyotype analysis and microarray analysis of amniotic fluid was retained during the operation. No typical chromosome abnormality or other abnormal genetic diagnosis was found. Conclusions: FPV colud be used as an effective intervention measure to promote the development of right ventricle in HRHS fetuses. The scientific management of multidisciplinary professional technical team in perioperative period is particularly important to ensure the success of FPV and the safety of pregnant women and fetuses.

Sudden unexpected death after acute symptomatic seizures in a patient on mechanical ventilation

BackgroundThe mechanism of sudden unexpected death in epilepsy remains poorly understood. Seizure induced cardiac arrhythmia, central and obstructive apneas have been proposed as possible causes of death. Here we report a unique case of seizure related sudden unexpected death in a patient whose airway was fully protected by intubation and mechanic ventilation in the absence of fatal cardiac arrhythmia.Case presentationA 70-year-old woman was undergoing mechanical ventilation and video-electroencephalography (EEG) monitoring following two convulsive seizures with ictal hypoventilation and hypoxemia. Several hours after intubation, she suffered another generalized tonic clonic seizure lasted for 3 min and developed postictal generalized EEG suppression in the presence of stable vital signs with SpO2 > 90%. EEG suppression persisted throughout the postictal phase. There was a significant fluctuation of systolic blood pressure between 50 and 180 mmHg with several bouts of hypotension < 60 mmHg. She remained unresponsive after the convulsive seizure and died of diffuse cerebral edema 12 h later. Autopsy revealed no clear cause of death, except for possible hypoxic and ischemic injury leading to the diffuse cerebral edema.ConclusionGiven the reliable periictal airway protection, neither seizure induced central apnea nor obstructive apnea appeared to be the direct cause of death in this unique case. In the absence of fatal cardiac arrhythmia, diffuse cerebral edema secondary to seizure-induced autonomic dysfunction, hypotension and hypoxemia might be the cause of death, highlighting the etiological heterogeneity of sudden unexpected death in epilepsy.

Influence of intradialytic systolic blood pressure changes on arteriovenous access thrombosis in maintenance hemodialysis patients.

Arteriovenous access (AV) thrombosis is an important and preventable problem amongst chronic hemodialysis (HD) patients. Systolic blood pressure (SBP) fluctuation relates to higher cardiovascular mortality amongst these patients. We proposed there is a close relation between SBP changes and arteriovenous (AV) access thrombosis. We also determined other risk factors and biochemical parameters related to AV access failure. 50 HD patients with thrombosis and 50 HD patients without thrombosis were included in the study. Odds ratios and 95% confidence intervals were estimated with multivariate-adjusted logistic regression models to determine the association between potential thrombosis-related risk factors and thrombosis risk. Elder adults, women, and patients with AV grafts, lower intradialytic SBP and higher SBP variations during HD sessions had higher incidence of AV access thrombosis. AV access infection and decreased blood flow (BF) velocity were associated with an increased incidence of thrombotic events, whereas the use of anti-thrombotic agents was associated with a decreased incidence of thrombotic events. Further, anaemia, hypoalbuminemia, hyperlipidemia, and impaired mineral metabolism parameters were also found to be associated with AV access thrombosis. Close monitoring and management of intradialytic hypotension and SBP fluctuation in every HD session are important. Some important and novel modifiable risk factors related to AV access thrombosis were identified in this study (eg, AV access infection, decreased BF and abnormal biochemical parameters, etc). Earlier surveillance and modification of these risk factors is crucial to prevent AV access failure in HD patients.

Effects of dexmedetomidine on heart rate control and pre-operative outcome in patients with acute aortic dissection: a propensity-matched analysis.

The total survival rate in patients with acute aortic dissection (AAD) has been greatly improved because of surgical technique advances. However, the pre-operative mortality rate remained high. In this study, we sought to evaluate the effects of dexmedetomidine (DEX) on heart rate control and preoperative outcome in AAD. Retrospectively enrolled 461 patients who were diagnosed with AAD during the first 7-day after admission and divided into two groups according to the use of intravenous DEX: DEX group (91 patients) and Control group (370 patients). The heart rate and systolic blood pressure (SBP) level in both groups were recorded, and the incidence of aortic dissection rupture and pre-operative survival rates within 7 days were considered as the primary clinical outcomes. Compared to the Control group, heart rate of DEX group in the early 3 hours was significantly higher (P=0.009), and the 24-hour heart rate fluctuation was smaller (P=0.012). There was no difference in the systolic blood pressure (SBP) between the two groups, but the 24-hour fluctuation of SBP in DEX group was less (P=0.003). We performed a propensity-matched analysis to minimize selection bias and found that there were 7 (7.9%) patients in the DEX group occurred acute pulmonary edema, 17 (19.1%) patients in the Control group (P=0.047). And the pre-operative survival rates within 7 days were significantly improved in DEX group (P=0.004). And the pre-operative survival rates within 7 days were significantly improved in DEX group (P=0.004). DEX can be beneficial to facilitate heart rate control, keep SBP more steady, and reduce the incidence of pre-operative aortic rupture in patients with AAD.

Prophylactic endovascular balloon occlusion of the aorta in cases of placenta accreta spectrum during caesarean section: points from the anaesthesiologist\u2019s perspective

BackgroundThe placenta accreta spectrum (PAS) is a severe complication of pregnancy and is associated with massive haemorrhage, hysterectomy, and even perinatal maternal-foetal death. Prophylactic abdominal aortic balloon occlusion (PAABO) is a novel and efficient therapy for these patients. The aim of this study was to investigate the benefits, potential risks, and characteristics of anaesthesia management.MethodsA total of 48 parturients with PAS were enrolled and divided into two groups. Group A (n = 25) received PAABO, and Group B (n = 23) underwent a normal operative procedure. The characteristics of the general parameters, anaesthesia, and operative procedure were noted. Data on vital signs including systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) during the operation were recorded. Before and after the procedure, hepatic and renal function and lactate dehydrogenase (LDH) were also measured.ResultsThe characteristics of the groups were comparable. PAABO significantly reduced estimated blood loss, which was ≥ 1000 ml. Drastic fluctuations in SBP, DBP and HR were observed during inflation and deflation in Group B. After the operation, increased LDH and glutamic oxaloacetic transaminase (GOT) were observed in both groups, and increased glutamic-pyruvic transaminase (GTP) was observed in Group B.ConclusionsPAABO reduced perioperative blood loss and the risk of hysterectomy among parturients with PAS. Sophisticated anaesthetic management should be implemented to prevent or reduce perioperative complications and address internal disorders that are caused by massive blood loss.