The impact of intraoperative blood pressure variability on the risk of postoperative adverse outcomes in non-cardiac surgery: a systematic review

Hemodynamic stability during surgery seems to account for positive postoperative outcomes in patients. However, little is known about the impact of intraoperative blood pressure variability (IBPV) on the postoperative complications. The aim was to investigate whether IBPV is associated with the development of postoperative complications and what is the nature of this association. We conducted a systematic search in PubMed, Medical Subject Headings, Embase, Web of Science, SCOPUS, clinicaltrials.gov, and Cochrane Library on the 8th of April, 2021. We included studies that only focused on adults who underwent primarily elective, non-cardiac surgery in which intraoperative blood pressure variation was measured and analyzed in regard to postoperative, non-surgical complications. We identified 11 papers. The studies varied in terms of applied definitions of blood pressure variation, of which standard deviation and average real variability were the most commonly applied definitions. Among the studies, the most consistent analyzed outcome was a 30-day mortality. The studies presented highly heterogeneous results, even after taking into account only the studies of best quality. Both higher and lower IBPV were reported to be associated for postoperative complications. Based on a limited number of studies, IBPV does not seem to be a reliable indicator in predicting postoperative complications. Existing premises suggest that either higher or lower IBPV could contribute to postoperative complications. Taking into account the heterogeneity and quality of the studies, the conclusions may not be definitive.

Effect of perioperative blood pressure variability on cerebral hyperperfusion syndrome after carotid artery stenting: A retrospective study

Objective To investigate the effect of perioperative blood pressure variability on cerebral hyperperfusion syndrome after carotid artery stenting. Methods A retrospective analysis was conducted of data collected from 418 patients who underwent carotid artery stenting in Guangxi Zhuang Autonomous Region People's Hospital in China. The blood pressure data were collected during operation (after balloon dilation, before stent release, after stent release) and within 3 days after the operation. The blood pressure variability was evaluated by measuring the mean, maximum, minimum, max–min, standard deviation (SD) of systolic blood pressure (SBP) and diastolic blood pressure (DBP). The correlation between blood pressure variability and cerebral hyperperfusion syndrome was analysed. Results Blood pressure data from 418 patients were analysed. Twenty patients (4.8%) developed cerebral hyperperfusion syndrome. The parameters of blood pressure variability were divided into four groups according to quartile. After adjusting for age, symptomatic carotid stenosis, unilateral carotid stenosis, bilateral carotid stenosis, collateral circulation, diabetes mellitus and chronic kidney disease, multivariate analysis showed that SBPMax, SBPMin, SBPMax−Min, SBPCV, DBPSD, DBPMax, DBPMin, DBPMax−Min and DBPCV were associated with the occurrence of cerebral hyperperfusion syndrome ( P < 0.05), respectively. Conclusion This study suggests that blood pressure variability during the perioperative period may increase the risk of cerebral hyperperfusion syndrome.

Visit-to-Visit Blood Pressure Variability and Longitudinal Tau Accumulation in Older Adults

Background: Elevated blood pressure variability (BPV) is predictive of dementia, independent of average blood pressure levels, but neuropathological mechanisms remain unclear. We examined whether BPV in older adults is related to tau accumulation in brain regions vulnerable to Alzheimer disease and whether relationships are modified by apoϵ4 carrier status. Methods: Two hundred eighty-six Alzheimer’s Disease Neuroimaging Initiative participants without history of dementia underwent 3 to 4 blood pressure measurements over 12 months and ≥1 tau positron emission tomography thereafter. BPV was calculated as variability independent of mean. Each scan determined tau burden (standardized uptake value ratio) for a temporal meta–region of interest, including burden from entorhinal cortex, amygdala, parahippocampus, fusiform, inferior temporal, and middle temporal. Bayesian linear growth modeling examined the role of BPV, apolipoprotein ϵ4 carrier status, and time on regional tau accumulation after controlling for several variables, including baseline hypertension. Results: Elevated BPV was related to tau accumulation at follow-up in a temporal meta-region, independent of average blood pressure levels (ß, 0.89 [95% credible interval, 0.86–0.92]) and especially in entorhinal cortex (ß, 2.57 [95% credible interval, 2.15–2.99]). Apoϵ4 carriers with elevated BPV had the fastest tau accumulation at follow-up (ß, 1.73 [95% credible interval, 0.47–3.03]). Conclusions: BPV is related to tau accumulation in brain regions vulnerable to Alzheimer disease, independent of average blood pressure. APOEϵ4 modified this relationship. Bidirectionality of findings is possible. BPV may represent a marker of vascular dysfunction related to early-stage tau pathology contributing to Alzheimer disease.

Association of Circulating Osteoprotegerin Level with Blood Pressure Variability in Patients with Chronic Kidney Disease

Circulating osteoprotegerin (OPG) is a biomarker for cardiovascular complications that are closely related to chronic kidney disease (CKD). To investigate the association between circulating OPG level with long-term visit-to-visit blood pressure variability (BPV) in patients with pre-dialysis CKD, a total of 1855 subjects with CKD from stage 1 to pre-dialysis stage 5 from a prospective cohort were analyzed. Long-term visit-to-visit BPV was determined by average real variability (ARV), standard deviation (SD), and coefficient of variation (CoV) of systolic and diastolic blood pressure (SBP and DBP). ARV of SBP (Adjusted β coefficient 0.143, 95% confidence interval 0.021 to 0.264) was significantly associated with serum OPG level. Although SD and CoV of SBP were not significantly associated with serum OPG level in multivariate linear regression analyses, restricted cubic spline visualized the linear correlation of serum OPG level with all of ARV, SD, and CoV. The association between serum OPG level and DBP variability was not significant. Subgroup analyses revealed that the association of serum OPG with BPV is more prominent in the subjects with Charlson comorbidity index ≤3 and in the subjects without history of diabetes mellitus. In conclusion, circulating OPG level is potentially associated with long-term visit-to-visit BPV in patients with pre-dialysis CKD.