Mean Arterial Pressure Research Articles

Pulmonary vasodilation during cardiopulmonary resuscitation – A randomized, controlled porcine study

BackgroundDuring resuscitation pulmonary artery pressure (PAP) increases. This reduces left ventricular filling, leading to decreased blood flow. Inhaled nitric oxide (iNO) produces selective pulmonary vasodilation. We hypothesized that iNO would lower PAP during resuscitation resulting in increased survival. Methods30 pigs (40 kg) were subjected to cardiac arrest for 9.5 min after myocardial ischemia induced by coronary artery occlusion of the left anterior descending artery and ventricular fibrillation. During resuscitation, the pigs were randomized to 40 ppm iNO or placebo. The primary outcome was return of spontaneous circulation (ROSC). Pigs achieving ROSC underwent 4-hours intensive care. ResultsThe ROSC rate was 9/14 (64%) in the control group and 11/16 (69%) in the iNO group (OR 1.2 95%CI [0.3;5.6], p > 0.99). There was no difference in diastolic aorta pressure/PAP ratio (mean difference −0.99 [95% CI: −2.33–0.36], p = 0.14). Mean pulmonary artery pressure was lower in the iNO group 60 and 120 min after ROSC (mean difference: −12.18 mmHg [95%CI: −16.94; −7.43] p < 0.01 and −5.43 [95%CI: −10.39; −0.46] p = 0.03). Troponin I levels in the iNO group were significantly higher 60 and 120 min after ROSC (mean difference: 266105 ng/l [95%CI: 6356; 525855] p = 0.045 and 420049 ng/l [95%CI: 136779; 703320], p = 0.004). The area at risk of the heart was 33% (SD 1) in controls and 34% (SD 1) in the iNO group. The infarct size divided by the area at risk was 55% (SD 3) in controls and 86% (SD 1) in the iNO group, p = 0.01. ConclusionApplication of iNO did not improve the rate of ROSC or hemodynamic function but increased myocardial injury.

A comparative evaluation of intraperitoneal bupivacaine alone and bupivacaine with dexmedetomidine for post-operative analgesia following laparoscopic cholecystectomy.

Intraperitoneal instillation of local anaesthetic agents alone or in combination with opioids, α2 agonists such as Dexmedetomidine have been found to reduce postoperative pain following laparoscopic cholecystectomy. The study was designed to compare the better drug among Bupivacaine alone and Bupivacaine with Dexmedetomidine with respect to their analgesic efficacy and safety profile. in patients undergoing laparoscopic cholecystectomy. The study was carried out on sixty patients of the American Society of Anaesthesiologists (ASA) physical status I-II of either sex with ages ranging from 18 to 60 years posted for elective laparoscopic cholecystectomy under General Anaesthesia, equally divided into two groups, randomly allocated to one of the Groups using the table of randomization. Group B received Intraperitoneal Bupivacaine 40 ml 0.25% +5 ml normal saline and Group BD received Intraperitoneal Bupivacaine 40 ml 0.25% + Dexmedetomidine1 μg/kg diluted in 5 ml Normal saline. The mean heart rate and blood pressure (systolic, diastolic and mean) readings were significantly lower in Group BD than in Group B. The mean duration of analgesia in our study was longer in Group BD (7.5 ± 0.73 hours) when compared to Group B (5.9 ± 0.55 hours) with p-value & 0.0001 and CI 1.27 to 1.9, which was statistically significant. However, the post-operative analgesic requirement (rescue/demand) in Group B was clinically earlier and statistically significant as compared to Group BD. Postoperative VAS score ≥3 was considered the benchmark for providing rescue analgesia in the form of injection of Diclofenac 75 mg IV. In our study, we observed the pain scores via VAS/NRS at 30 min, 1 h, 2 h, 4 h, 6 h, 8 h, 10 h, 12 h, 14 h, 16 h, 18 h, 20 h, 22 h and 24 h postoperatively. A comparison of pain scores from 30 min to 10hrs postoperatively showed a significant difference in both Groups with Group B having significantly higher VAS scores and lower VAS scores with Group BD. Our study suggests that there is a shorter duration of action of 0.25% Bupivacaine alone as compared to 0.25% Bupivacaine + Dexmedetomidine. Since the laparoscope is still inside the abdominal cavity the drugs are easy to administer with no adverse effects and with a good safety profile because of the visualization of drug deposition in the right place. Intraperitoneal instillation of Bupivacaine with Dexmedetomidine for postoperative analgesia was very promising as a part of multimodal analgesia in laparoscopic cholecystectomy.

Evaluation of lingual oscillometric blood pressure measurement in anaesthetized pigs

ObjectiveTo evaluate the agreement between measurements of invasive blood pressure (IBP) and oscillometric blood pressure from the tongue (OBPton) using a multiparameter monitor. Study designUnblinded, prospective, experimental study. AnimalsA total of 12 female Large White crossbreed pigs. MethodsPigs undergoing experimental procedures that required arterial cannula placement were recruited. A blood pressure cuff with the closest width to 40% of the circumference of the tongue was placed rostral to the lingual frenulum. Systolic, mean and diastolic IBP and OBPton were measured simultaneously at 5 minute intervals. Agreement between paired measurements was examined using Bland–Altman analysis. Mean bias, precision (standard deviation of mean bias), 95% limits of agreement, correlation coefficients and percentage of measurements within 10 and 20 mmHg of IBP were calculated. ResultsThe total numbers of paired measurements recorded were 124, 126 and 124 for systolic, mean and diastolic blood pressures, respectively. The mean bias, precision and 95% limits of agreement for systolic OBPton were 11.5, 11.5 (–11.1 to 34.2), for mean OBPton 5.6, 5.7 (–5.7 to 16.8) and for diastolic OBPton 7.6, 10.1 (–12.1 to 27.4) mmHg. Correlation coefficients were greater than 0.9 for mean OBPton only. More than 50% of measurements were within 10 mmHg of IBP and 80% of measurements were within 20 mmHg of IBP for mean and diastolic OBPton only. Conclusions and clinical relevanceThe tongue as a cuff site for oscillometric blood pressure measurement is a useful site for measuring mean arterial, but not systolic or diastolic blood pressure in anaesthetized Large White crossbreed pigs. This technique fulfils the American College of Veterinary Internal Medicine criteria for measuring mean arterial pressure but not systolic or diastolic arterial pressure.

A porcine model of thoracic aortic aneurysms created with a retrievable drug infusion stent graft mirrors human aneurysm pathophysiology

ObjectiveAneurysm pathophysiology remains poorly understood, in part from the disparity of murine models with human physiology and the requirement for invasive aortic exposure to apply agents used to create aneurysm models. A retrievable drug infusion stent graft (RDIS) was developed to isolate the aortic wall intraluminally for drug exposure. We hypothesized that an RDIS could deliver aneurysm-promoting enzymes to create a porcine model of thoracic aneurysms without major surgical exposure. MethodsRetrievable nitinol stent graft frames were designed with an isolated drug delivery chamber, covered with polytetrafluoroethylene, and connected to a delivery wire with a drug infusion catheter installed to the outer chamber. Institutional Animal Care and Use Committee-approved Yorkshire pigs (n = 5) underwent percutaneous access of the femoral artery, baseline aortogram and stent placement in the thoracic aorta followed by 30-minute exposure to a cocktail of elastase, collagenase, and trypsin. After aspiration of excess drug, stent retrieval, and femoral artery repair, animals were recovered, with angiograms at 1 and 4 weeks followed by explant. Histological analysis, in situ zymography, and multiplex cytokine assays were performed. ResultsThe RDIS isolated a segment of anterior aorta angiographically, while the center lumen preserved distal perfusion during drug treatment (baseline femoral mean arterial pressure, 70 ± 14 mm Hg; after RDIS, 75 ± 12; P = .55). Endovascular induction of thoracic aneurysms did not require prior mechanical injury and animals revealed no evidence of toxicity. Within 1 week, significant aneurysmal growth was observed in all five animals (1.4 ± 0.1 cm baseline to 2.9 ± 0.7 cm; P = .002) and only within the treated region of the aorta. Aneurysms persisted out to 4 weeks. Aneurysm histology demonstrated loss of elastin and collagen that was otherwise preserved in untreated aorta. Proinflammatory cytokines and increased matrix metalloproteinase activity were increased significantly within the aneurysm. ConclusionsAn RDIS achieves isolated drug delivery while preserving distal perfusion to achieve an endovascular porcine model of thoracic aneurysms without major surgery. This model may have value for surgical training, device testing, and to better understand aneurysm pathogenesis. Most important, although the RDIS was used to simulate aortic pathology, this tool offers intriguing horizons for focused therapeutic drug delivery directly to aneurysms and, more broadly, focused locoregional drug delivery to vessels and vascular beds.

Risk prediction of kalaemia disturbance and acute kidney injury after total knee arthroplasty: use of a machine learning algorithm

IntroductionTotal knee arthroplasty (TKA) is a procedure associated with risks of electrolyte and kidney function disorders, which are rare but can lead to serious complications if not correctly identified. A routine check-up is very often carried out to assess the seric ionogram and kidney function after TKA, that rarely requires clinical intervention in the event of a disturbance. The aim of this study was to identify perioperative variables that would lead to the creation of a machine learning model predicting the risk of kalaemia disorders and/or acute kidney injury after total knee arthroplasty. HypothesisA predictive model could be constructed to estimate the risk of kalaemia disorders and/or acute kidney injury after total knee arthroplasty. Material and methodsThis single-centre retrospective study included 774 total knee arthroplasties (TKA) operated on between January 2020 and March 2023. Twenty-five preoperative variables were incorporated into the machine learning model and filtered by a first algorithm. The most predictive variables selected were used to construct a second algorithm to define the overall risk model for postoperative kalaemia and/or acute kidney injury (K+ A). Two groups were formed of K+ A and non-K+ A patients after TKA. A univariate analysis was performed and the performance of the machine learning model was assessed by the area under the curve representing the sensitivity of the model as a function of 1 - specificity. ResultsOf the 774 patients included who had undergone TKA surgery, 46 patients (5.9%) had a postoperative kalaemia disorder requiring correction and 13 patients (1.7%) had acute kidney injury, of whom 5 patients (0.6%) received vascular filling. Eight variables were included in the machine learning predictive model, including body mass index, age, presence of diabetes, operative time, lowest mean arterial pressure, Charlson score, smoking and preoperative glomerular filtration rate.Overall performance was good with an area under the curve of 0.979 [CI95% 0.938 - 1.02], sensitivity was 90.3% [CI95% 86.2 - 94.4] and specificity 89.7% [CI95% 85.5 - 93.8]. The tool developed to assess the risk of impaired kalaemia and/or acute kidney injuryafter TKA is available on https://arthrorisk.com. ConclusionThe risk of kalaemia disturbance and postoperative acute kidney injury after total knee arthroplasty could be predicted by a model that identifies low-risk and high-risk patients based on eight pre- and intraoperative variables. This machine learning tool is available on a web platform accessible for everyone, easy to use and has a high predictive performance. The aim of the model was to better identify and anticipate the complications of dyskalaemia and postoperative acute kidney injury in high-risk patients. Further prospective multicentre series are needed to assess the value of a systematic postoperative biochemical work-up in the absence of risk predicted by the model. Level of evidenceIV; retrospective study of case series.

Methylene Blue in Septic Shock: A Systematic Review and Meta-Analysis.

Although clinicians may use methylene blue (MB) in refractory septic shock, the effect of MB on patient-important outcomes remains uncertain. We conducted a systematic review and meta-analysis to investigate the benefits and harms of MB administration in patients with septic shock. We searched six databases (including PubMed, Embase, and Medline) from inception to January 10, 2024. We included randomized clinical trials (RCTs) of critically ill adults comparing MB with placebo or usual care without MB administration. Two reviewers performed screening, full-text review, and data extraction. We pooled data using a random-effects model, assessed the risk of bias using the modified Cochrane tool, and used Grading of Recommendations Assessment, Development, and Evaluation to rate certainty of effect estimates. We included six RCTs (302 patients). Compared with placebo or no MB administration, MB may reduce short-term mortality (RR [risk ratio] 0.66 [95% CI, 0.47-0.94], low certainty) and hospital length of stay (mean difference [MD] -2.1 d [95% CI, -1.4 to -2.8], low certainty). MB may also reduce duration of vasopressors (MD -31.1 hr [95% CI, -16.5 to -45.6], low certainty), and increase mean arterial pressure at 6 hours (MD 10.2 mm Hg [95% CI, 6.1-14.2], low certainty) compared with no MB administration. The effect of MB on serum methemoglobin concentration was uncertain (MD 0.9% [95% CI, -0.2% to 2.0%], very low certainty). We did not find any differences in adverse events. Among critically ill adults with septic shock, based on low-certainty evidence, MB may reduce short-term mortality, duration of vasopressors, and hospital length of stay, with no evidence of increased adverse events. Rigorous randomized trials evaluating the efficacy of MB in septic shock are needed. Center for Open Science (https://osf.io/hpy4j).

The left ventricle increases contractility in response to baroreceptor unloading, which is sympathetically mediated in the anesthetized rat.

Contemporary discussion of the baroreflex includes the efferent vascular-sympathetic and cardiovagal arms. Since sympathetic postganglionic neurons also innervate the left ventricle (LV), it is often assumed that the LV produces a sympathetically mediated increase in contractility during baroreceptor unloading, but this has not been characterized using a load-independent index of contractility. We aimed to determine 1) whether LV contractility increases in response to baroreceptor unloading and 2) whether such increases are mediated via the sympathetic or parasympathetic arm of the autonomic nervous system. Ten male Wistar rats were anesthetized (urethane) and instrumented with arterial and LV pressure-volume catheters to measure mean arterial pressure (MAP) and load-independent LV contractility [maximal rate of increase in pressure adjusted to end-diastolic volume (PAdP/dtmax)], respectively. Rats were placed in a servo-controlled lower-body negative pressure (LBNP) chamber to reduce MAP by 10% for 60 s to mechanically unload baroreceptors under control conditions. LBNP was repeated in each animal following infusions of cardiac autonomic blockers using esmolol (sympathetic), atropine (parasympathetic), and esmolol + atropine. Under control conditions, PAdP/dtmax increased during baroreceptor unloading (26 ± 6 vs. 31 ± 9 mmHg·s-1·μL-1, P = 0.031). During esmolol, there was no increase in LV contractility during baroreceptor unloading (11 ± 2 vs. 12 ± 2, P = 0.125); however, during atropine, there was an increase in LV contractility during baroreceptor unloading (26 ± 6 vs. 31 ± 9, P = 0.019). During combined esmolol and atropine, there was a small increase in contractility versus control (13 ± 3 vs. 15 ± 4, P = 0.046). Our results demonstrate that, in anesthetized rats, LV contractility increases in response to baroreceptor unloading, which is largely sympathetically mediated.NEW & NOTEWORTHY This study empirically demonstrates a sympathetically mediated increase in LV contractility in response to baroreceptor unloading using a load-independent index of cardiac contractility in the anesthetized rat.

Effect of dexmedetomidine on the incidence of postoperative acute kidney injury in living donor liver transplantation recipients: A randomized controlled trial.

Acute kidney injury (AKI) is one of the most common complications after living-donor liver transplantation (LDLT) that has great impact on recipient and graft outcomes. Dexmedetomidine is reported to decrease the incidence of AKI. In the current study, we investigated whether intraoperative dexmedetomidine infusion would reduce the AKI following LDLT. In total, 205 adult patients undergoing elective LDLT were randomly assigned to the dexmedetomidine group (n=103) or the control group (n=102). Dexmedetomidine group received continuous dexmedetomidine infusion at a rate of 0.4mcgּ/kg/hr after the anesthesia induction until 2 hours after graft reperfusion. The primary outcome was to compare the incidence of AKI. Secondary outcomes included serial lactate levels during surgery, chronic kidney disease, major adverse cardiovascular events, early allograft dysfunction, graft failure, overall mortality, duration of mechanical ventilation, ICU and hospital length of stay. Intraoperative hemodynamic parameters were also collected. Of 205 recipients, 42.4% (n=87) developed AKI. The incidence of AKI was lower in the dexmedetomidine group (35.0%, n=36/103) compared with the control (50.0%, n=51/102) ( P =0.042). There were significantly lower lactate levels in the dexmedetomidine group after reperfusion (4.39 [3.99-4.8] vs 5.02 [4.62-5.42], P =0.031) until the end of surgery (4.23 [3.73-4.73] vs 5.35 [4.84-5.85], P =0.002). There were no significant differences in the other secondary outcomes besides lactate. Also, intraoperative mean blood pressure, cardiac output, and systemic vascular resistance did not show any difference. Our study suggests that intraoperative dexmedetomidine administration was associated with significantly decreased AKI incidence and lower intraoperative serum lactate levels in LDLT recipients, without untoward hemodynamic effects.

DeliVERy of Optimal blood pressure coNtrol in afrICA (VERONICA)-Nigeria study: Rationale and Design of a Randomised Clinical Trial

BackgroundBlood pressure (BP) control among treated patients in Africa is very suboptimal, with low levels of combination therapy use and therapeutic inertia being among the major barriers to effective control of hypertension. The VERONICA-Nigeria study aims to evaluate, among Black African adults with hypertension, the effectiveness and safety of a triple pill-based treatment protocol compared to Nigeria hypertension treatment protocol for the treatment of hypertension. MethodsThis study involves a randomised, parallel-group and open-label trial. Adults with uncontrolled hypertension (n=300), untreated or receiving monotherapy, with no contraindication to study treatments will be randomly assigned 1:1 to treatment with a triple pill based-treatment protocol or Nigeria hypertension treatment protocol. Follow-up is for 6 months, with interim follow up visits at month 1, 2, and 3. In a non-comparative extension treatment period, participants completing the 6 months randomised period and on ≤3 BP-lowering drugs will receive treatment with the triple pill-based treatment protocol for 12 months. The primary outcome is change in home mean SBP from baseline to month 6, and key secondary efficacy outcome is percentage of participants with clinic BP <140/90 mmHg at month 6. The primary safety outcome is discontinuation of trial treatment due to adverse events from randomization to month 6. Economic evaluation will be conducted to assess the cost-effectiveness of the triple pill-based treatment protocol, and process evaluation will be conducted to understand the context in which the trial was conducted, implementation of the trial and interventions and mechanisms of effect, and potential barriers and facilitators to implementing the intervention in clinical practice. ConclusionThe VERONICA-Nigeria trial will provide evidence of effectiveness and safety of the triple-based treatment protocol for the pharmacological management of hypertension, in Black African adults. Trial RegistrationPACTR202107579572114

Incorporating Maternal Blood Pressure Screening Into Routine Newborn Clinic Visits

Background and ObjectivesIn the immediate postpartum period, mothers often prioritize newborn care over postpartum follow-up. There is an increasing contribution of hypertensive disorders of pregnancy (HDP) to maternal morbidity and mortality. In this feasibility study, we sought to implement maternal postpartum blood pressure (BP) screening in a newborn clinic. MethodsWe conducted a non-randomized, prospective feasibility study to evaluate the application of maternal BP screening at newborn clinic visits. An elevated BP was defined as a systolic pressure (SBP) of ≥140 mmHg or a diastolic pressure (DBP) of ≥90 mmHg. BPs were triaged with a standardized algorithm, utilizing support and expertise of on-call maternal subspecialists. ResultsWe screened 72 postpartum individuals, with a mean SBP of 130±19 mmHg and DBP 86±12 mmHg. Most were publicly insured (78%) and self-identified as Black (69%). Of the 31 (43%) with an elevated BP, 13 (42%) did not have a known HDP. Of those without known HDP, 4 were diagnosed with postpartum preeclampsia and 2 with postpartum hypertension. One individual diagnosed with new-onset postpartum preeclampsia was triaged to the emergency department. Only 56% of women attended a obstetrics appointment within 12 weeks after delivery. ConclusionsThis study demonstrates the feasibility of an innovative maternal postpartum BP assessment in a racially and socioeconomically diverse pediatrics clinic. Through collaborative care, individuals were able to be safely triaged, thus providing an opportunity to identify at-risk individuals who could benefit from earlier identification and management of hypertension. Pediatricians have a unique opportunity to contribute to postpartum maternal health.

A conflict choice of treatment during defibrillation in cardiopulmonary resuscitation: Lidocaine, amiodarone or both? A retrospective study

A conflict choice of treatment during defibrillation in cardiopulmonary resuscitation: Lidocaine, amiodarone or both? A retrospective study

Construction and validation of a risk prediction model for postoperative delirium in patients with off‑pump coronary artery bypass grafting.

Compared with cardiopulmonary bypass surgery, off-pump coronary artery bypass grafting (OPCABG) reduces trauma to the body. However, there is still a risk of neurological complications, including postoperative delirium (POD). To date, few studies have been conducted on the risk of POD in OPCABG patients, and no standardized prediction model has been established. Thus, this study sought to analyze the factors influencing POD in OPCABG patients and to construct a risk prediction model. A total of 1,258 patients with OPCABG were enrolled and divided into the training set for model construction (944 cases) and the test set for model validation (314 cases). A risk prediction model for POD in OPCABG patients was established by least absolute shrinkage and selection operator (LASSO) regression and multivariate logistic regression, and a nomogram was drawn. The discrimination and calibration degree of the model was evaluated by the receiver operator characteristic (ROC) curve and calibration curve. Eight variables [i.e., age, tissue oxygen saturation, mean arterial pressure (MAP), carotid stenosis, the anterior-posterior diameter of the aortic sinus, ventricular septum thickness, left ventricular ejection fraction (LVEF), and Mini-Mental State Examination (MMSE) scores] were screen out by the LASSO regression and multivariate logistic regression, and the model was constructed. The area under the ROC curve of the training set was 0.702 [95% confidence interval (CI): 0.662-0.743], and that of the test set was 0.658 (95% CI: 0.585-0.730). The results of the Hosmer-Lemeshow goodness-of-fit test showed that the predicted POD risk of OPCABG patients in the training and test sets was consistent with the actual POD risk (χ2=5.154, P=0.74). The occurrence of POD in OPCABG patients is related to age, tissue oxygen saturation, MAP, carotid artery stenosis, the anterior-posterior diameter of aortic sinus, ventricular septal thickness, LVEF, and MMSE scores. The prediction model constructed with the above variables had high predictive performance, and thus may be helpful in the early identification of such patients.

Perioperative optic nerve sheath diameter variations in patients with end-stage renal failure undergoing robotic-assisted kidney transplant: a prospective observational study.

Patients with chronic kidney disease (CKD) who undergo hemodialysis are predisposed to interstitial cerebral edema. Robotic-assisted laparoscopic surgery can increase optic nerve sheath diameter (ONSD) and intracranial pressure. The impact of robotic-assisted kidney transplant (RAKT) on ONSD is complicated by the presence of CKD, the administration of furosemide and mannitol, and the manipulation of hemodynamics. We examined ONSD variations in patients undergoing RAKT over a 1-year period at our institution. Furthermore, we attempted to identify any perioperative hemodynamic factors influencing these changes. This prospective study included 20 patients undergoing RAKT. ONSD, heart rate, central venous pressure, systolic blood pressure, diastolic blood pressure (DBP), and mean arterial pressure (MAP) were measured following intubation (T1), after assuming the steep Trendelenburg position (T2), 1 hour after docking (T3), upon reperfusion (T4), after transition to the supine position (T5), and 3 hours postextubation (T6). Repeated measures analysis of variance with post hoc Bonferroni correction was employed to compare variables at each time point. Pearson correlation analysis was utilized to assess relationships between variables. P-values ≤0.05 were considered to indicate statistical significance. ONSD (in mm) increased from T1 (3.60±0.44) to T3 (4.06±0.45, P=0.002) and T4 (3.99±0.62, P=0.046), before falling to its lowest value at T6 (3.42±0.64, P=0.002). Pearson correlation analysis revealed significant correlations (P<0.05) between changes in ONSD at T3 and both DBP (r=0.637) and MAP (r=0.522). During RAKT with open ureteric anastomosis, ONSD initially increased, then decreased following reperfusion. DBP and MAP displayed positive correlations with ONSD changes at T3.

H2S donor GYY4137 mitigates sFlt-1-induced hypertension and vascular dysfunction in pregnant rats

Abstract Gestational hypertension, often associated with elevated soluble Fms-related receptor tyrosine kinase 1 (sFlt-1), poses significant risks to both maternal and fetal health. Hydrogen sulfide (H2S), a gasotransmitter, has demonstrated blood pressure-lowering effects in hypertensive animals and humans. However, its role in pregnancy-induced hypertension remains unclear. This study investigated the impact of GYY4137, a slow-release H2S donor, on sFlt-1-induced hypertension in pregnant rats . Pregnant rats were administered sFlt-1 (6 μg/kg/day, intravenously) or vehicle from gestation day (GD) 12–20. A subset of these groups received GYY4137 ( 50 mg/kg/day, intraperitoneal) from GD 16–20. Serum H2S levels, mean arterial blood pressure, uterine artery blood flow, and vascular reactivity were assessed. Elevated sFlt-1 reduced both maternal weight gain and serum H2S levels. GYY4137 treatment restored both weight gain and H2S levels in sFlt-1 dams. sFlt-1 increased mean arterial pressure and decreased uterine artery blood flow in pregnant rats. However, treatment with GYY4137 normalized blood pressure and restored uterine blood flow in sFlt-1 dams. sFlt-1 dams exhibited heightened vasoconstriction to phenylephrine and GYY4137 significantly mitigated the exaggerated vascular contraction. Notably, sFlt-1 impaired endothelium-dependent relaxation, while GYY4137 attenuated this impairment by upregulating eNOS protein levels and enhancing vasorelaxation in uterine arteries. GYY4137 mitigated sFlt-1-induced fetal growth restriction. In conclusion, sFlt-1 mediated hypertension is associated with decreased H2S levels. Replenishing H2S with the donor GYY4137 mitigates hypertension and improves vascular function and fetal growth outcomes. This suggests modulation of H2S could offer a novel therapeutic strategy for managing gestational hypertension and adverse fetal effects.

Comparison of Prophylactic Phenylephrine Infusion and Rescue Bolus Administration for Maintaining Blood Pressure During Spinal Anaesthesia for Caesarean Delivery in Obese Parturient: A Randomised Control Trial.

Phenylephrine (PE) is one of the vasopressor used to treat hypotension during anaesthesia. The primary aim of this study was to compare the effect of prophylactic infusion and rescue bolus of PE on the haemodynamic changes during spinal anaesthesia (SA) for Caesarean section (CS) in obese parturients. A total of 74 obese parturients scheduled for elective CS under SA were randomised into two groups; Group A (n = 37) received prophylactic PE infusion starting at 50 μg min-1 and adjusted according to the given algorithm and Group B (n = 37) received 100 μg PE bolus to treat hypotension. The measured parameters were systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), the total requirement of PE and neonatal Apgar score. Six patients were excluded from the analysis due to missing data and only 68 were analysed. Group A showed significantly higher SBP, DBP and MAP than Group B (P < 0.05). The requirement of PE was higher in Group A than Group B [817.7 (265.7) μg versus 360.6 (156.0) μg; P = < 0.05]. Both groups had no difference in terms of the neonatal Apgar score. Prophylactic PE infusion provided better haemodynamic control than therapeutic boluses in obese parturients undergoing CS under SA.

Centhaquine Increases Stroke Volume and Cardiac Output in Patients with Hypovolemic Shock.

Introduction: Centhaquine is a resuscitative agent that acts on α2B adrenergic receptors. Its effect on cardiac output in hypovolemic shock patients has not been reported. Methods: This pilot study was conducted in 12 hypovolemic shock patients treated with centhaquine who participated in an open-label phase IV study (NCT05956418). Echocardiography was utilized to measure stroke volume (SV), cardiac output (CO), left ventricular outflow tract velocity time integral (LVOT-VTI) and diameter (LVOTd), heart rate (HR), left ventricular ejection fraction (LVEF) and fractional shortening (LVFS), and inferior vena cava (IVC) diameter before (0 min) and 60, 120, and 300 min after centhaquine (0.01 mg/kg) iv infusion for 60 min. Results: SV was significantly increased after 60, 120, and 300 min. CO increased significantly after 120 and 300 min despite a decrease in HR. IVC diameter and LVOT-VTI at these time points significantly increased, indicating the increased venous return. LVEF and LVFS did not change, while the mean arterial pressure (MAP, mmHg) increased after 120 and 300 min. Positive correlations between IVC diameter and SV (R2 = 0.9556) and between IVC diameter and MAP (R2 = 0.8928) were observed, which indicated the effects of an increase in venous return on SV, CO, and MAP. Conclusions: Centhaquine-mediated increase in venous return is critical in enhancing SV, CO, and MAP in patients with hypovolemic shock; these changes could be pivotal for reducing shock-mediated circulatory failure, promoting tissue perfusion, and improving patient outcomes. Trial Registration: CTRI/2021/01/030263 and NCT05956418.

Risk factors associated with intraoperative persistent hypotension in pancreaticoduodenectomy.

Intraoperative persistent hypotension (IPH) during pancreaticoduodenectomy (PD) is linked to adverse postoperative outcomes, yet its risk factors remain unclear. To clarify the risk factors associated with IPH during PD, ensuring patient safety in the perioperative period. A retrospective analysis of patient records from January 2018 to December 2022 at the First Affiliated Hospital of Nanjing Medical University identified factors associated with IPH in PD. These factors included age, gender, body mass index, American Society of Anesthesiologists classification, comorbidities, medication history, operation duration, fluid balance, blood loss, urine output, and blood gas parameters. IPH was defined as sustained mean arterial pressure < 65 mmHg, requiring prolonged deoxyepinephrine infusion for > 30 min despite additional deoxyepinephrine and fluid treatments. Among 1596 PD patients, 661 (41.42%) experienced IPH. Multivariate logistic regression identified key risk factors: increased age [odds ratio (OR): 1.20 per decade, 95% confidence interval (CI): 1.08-1.33] (P < 0.001), longer surgery duration (OR: 1.15 per additional hour, 95%CI: 1.05-1.26) (P < 0.01), and greater blood loss (OR: 1.18 per 250-mL increment, 95%CI: 1.06-1.32) (P < 0.01). A novel finding was the association of arterial blood Ca2+ < 1.05 mmol/L with IPH (OR: 2.03, 95%CI: 1.65-2.50) (P < 0.001). IPH during PD is independently associated with older age, prolonged surgery, increased blood loss, and lower plasma Ca2+.

Norepinephrine weaning guided by the Hypotension Prediction Index in vasoplegic shock after cardiac surgery: protocol for a single-centre, open-label randomised controlled trial – the NORAHPI study

IntroductionNorepinephrine (NE) is the first-line recommended vasopressor for restoring mean arterial pressure (MAP) in vasoplegic syndrome (vs) following cardiac surgery with cardiopulmonary bypass. However, solely focusing on target MAP values...

The Association Between BMI and Cardiorespiratory Functions Among Medical Students at Northern Border University.

Cardiorespiratory function is one of the key health indicators that promotegood health. Knowing the correlation between body mass index (BMI) and cardiorespiratory functioning might assist in the creation of evidence-based therapies that focus on addressing difficulties associated with obesity. To assess the correlation between BMI and cardiorespiratory functions among medical students at Northern Border University. A cross-sectional study was conducted among medical students at Northern Border University, Saudi Arabia. The blood pressure (BP), respiratory rate (RR), heart rate (HR), mean arterial pressure (MAP), pulse pressure (PP), and BMI of the students were measured. The mean age of the students was 17.1 ± 1.9 years. Nearly 40% of students were overweight or obese. Our study revealed a significant positive correlation between BMI and BP, RR, tidal volume (TV), and MAP. The correlation analysis of our study revealed a significant positive correlation of BMI with BP, RR, TV, and MAP.

The Total Denervation of the Ischemic Kidney Induces Differential Responses in Sodium Transporters' Expression in the Contralateral Kidney in Goldblatt Rats.

The Goldblatt model of hypertension (2K-1C) in rats is characterized by renal sympathetic nerve activity (rSNA). We investigated the effects of unilateral renal denervation of the clipped kidney (DNX) on sodium transporters of the unclipped kidneys and the cardiovascular, autonomic, and renal functions in 2K-1C and control (CTR) rats. The mean arterial pressure (MAP) and rSNA were evaluated in experimental groups. Kidney function and NHE3, NCC, ENaCβ, and ENaCγ protein expressions were assessed. The glomerular filtration rate (GRF) and renal plasma flow were not changed by DNX, but the urinary (CTR: 0.0042 ± 0.001; 2K-1C: 0.014 ± 0.003; DNX: 0.005 ± 0.0013 mL/min/g renal tissue) and filtration fractions (CTR: 0.29 ± 0.02; 2K-1C: 0.51 ± 0.06; DNX: 0.28 ± 0.04 mL/min/g renal tissue) were normalized. The Na+/H+ exchanger (NHE3) was reduced in 2K-1C, and DNX normalized NHE3 (CTR: 100 ± 6; 2K-1C: 44 ± 14, DNX: 84 ± 13%). Conversely, the Na+/Cl- cotransporter (NCC) was increased in 2K-1C and was reduced by DNX (CTR: 94 ± 6; 2K-1C: 144 ± 8; DNX: 60 ± 15%). In conclusion, DNX in Goldblatt rats reduced blood pressure and proteinuria independently of GRF with a distinct regulation of NHE3 and NCC in unclipped kidneys.