Machine learning model based on RCA-PDCA nursing methods and differentiating factors to predict hypotension during cesarean section surgery.

BACKGROUND: Intraoperative hypotension during cesarean section has become a serious complication for maternal and fetal healthy. It is commonly encountered by subarachnoid anesthesia. However, currently used control methods have varying degrees of side effects, such as drugs. The Root Cause Analysis (RCA) - Plan, Do, Check, Act (PDCA) is a new model of care that identifies the root causes of problems. The study aimed to demonstrate the usefulness of RCA-PDCA nursing methods in preventing intraoperative hypotension during cesarean section and to predict the occurrence of intraoperative hypotension through a machine learning model. METHODS: Patients who underwent cesarean section at Traditional Chinese Medicine of Southwest Medical University from January 2023 to December 2023 were retrospectively screened, and the data of their gestational times, age, height, weight, history of allergies, intraoperative vital signs, fetal condition, operative time, fluid out and in, adverse effects, use of vasopressor drugs, anxiety-depression-pain scores, and satisfaction were collected and analyzed. The statistically different features were screened and five machine learning models were used as predictive models to assess the usefulness of the RCA-PDCA model of care. RESULTS: (1) Compared with the general nursing model, the RCA-PDCA nursing model significantly reduces the incidence of intraoperative hypotension and postoperative complications in cesarean delivery, and the patient experience is comfortable and satisfactory. (2) Among the five machine learning models, the RF model has the best predictive performance, and the accuracy of the random forest model in preventing intraoperative hypotension is as high as 90%. CONCLUSION: Through computer machine learning model analysis, we prove the importance of the RCA-PDCA nursing method in the prevention of intraoperative hypotension during cesarean section, especially the Random Forest model which performed well and promoted the application of artificial intelligence computer learning methods in the field of medical analysis.

High dose cholecalciferol supplementation causing morning blood pressure reduction in patients with type 1 diabetes mellitus and cardiovascular autonomic neuropathy.

We evaluated the association of cardiovascular autonomic neuropathy (CAN), blood pressure (BP) and Vitamin D (VD) levels before and after high-dose cholecalciferol supplementation (4000/10,000) UI/day) for 12 weeks in patients (N = 67) with type 1 diabetes mellitus (T1DM). Based on this prospective controlled pilot study, patients were divided into group 1 (N = 23 with CAN) and group 2 (N = 44 without CAN). At baseline, group 1 had higher systolic BP (SBP) during sleep (115 ± 14 vs. 107 ± 12 mmHg, p = 0.04) and lower nocturnal dipping (3 ± 5 vs. 8 ± 6%, p = 0.009). Among those with loss of nocturnal dipping, 45.4% (20/44) had CAN, while in normal nocturnal dipping group it occurred only in 13% (3/23) (p = 0.007). Non-dipper group had worse CAN parameters when compared to dipper group [Very low frequency (VLF) (2.5 ± 0.5vs.2.8 ± 0.4 s, p = 0.01), total power (TP) (2.9 ± 0.6 vs. 3.3 ± 0.4 s, p = 0.01), Valsalva coefficient (1.5 ± 0.4 vs. 1.8 ± 0.6, p = 0.06)]. After VD, only group 1 improved CAN parameters [TP (2.5 ± 0.4 vs. 2.8 ± 0.6, p = 0.01) and VLF (2.2 ± 0.4 vs. 2.4 ± 0.5, p = 0.03). Group 1 presented a reduction in morning SBP (120 ± 20 vs. 114 ± 17 mmHg, p = 0.038) and in morning SBP surge (13 ± 13 vs. 5 ± 14, p = 0.04). High-dose VD was associated with improved CAN parameters and reduced awake SBP and morning SBP surge. These findings suggest that VD may benefit patients with cardiovascular autonomic neuropathy. ISRCTN32601947, registration date: 31/07/2017.

The contribution of sodium reduction and potassium increase to the blood pressure lowering observed in the Salt Substitute and Stroke Study.

The Salt Substitute and Stroke Study (SSaSS) demonstrated significant reductions in systolic blood pressure (SBP), and the risk of stroke, major cardiovascular events and total mortality with the use of potassium-enriched salt. The contribution of sodium reduction versus potassium increase to these effects is unknown. We identified four different data sources describing the association between sodium reduction, potassium supplementation and change in SBP. We then fitted a series of models to estimate the SBP reductions expected for the differences in sodium and potassium intake in SSaSS, derived from 24-h urine collections. The proportions of the SBP reduction separately attributable to sodium reduction and potassium supplementation were calculated. The observed SBP reduction in SSaSS was -3.3 mmHg with a corresponding mean 15.2 mmol reduction in 24-h sodium excretion and a mean 20.6 mmol increase in 24-h potassium excretion. Assuming 90% of dietary sodium intake and 70% of dietary potassium intake were excreted through urine, the models projected falls in SBP of between -1.67 (95% confidence interval: -4.06 to +0.73) mmHg and -5.33 (95% confidence interval: -8.58 to -2.08) mmHg. The estimated proportional contribution of sodium reduction to the SBP fall ranged between 12 and 39% for the different models fitted. Sensitivity analyses assuming different proportional urinary excretion of dietary sodium and potassium intake showed similar results. In every model, the majority of the SBP lowering effect in SSaSS was estimated to be attributable to the increase in dietary potassium rather than the fall in dietary sodium.

Successful treatment of severe calcium channel blocker poisoning, new experience with the guidance of invasive hemodynamic monitoring in a 17-year-old girl: a case report.

BACKGROUND: Calcium channel blocker poisoning is one of the most lethal cardiac drugs overdoses. Calcium and high-dose insulin infusion are the first-line therapy for symptomatic patients, and Intralipid emulsion infusion is useful for refractory cases. CASE PRESENTATION: In this report, we describe a 17-year-old Iranian girl who took 250 mg of the drug for a suicidal attempt and presented with refractory hypotension and non-cardiogenic pulmonary edema treated successfully with the guidance of invasive hemodynamic parameters. CONCLUSION: For complicated cases, in addition to supportive care and adjuvant therapy such as high-dose insulin and Intralipid, it is mandatory to utilize advanced hemodynamic monitoring to treat hypotension in severe calcium channel blocker poisoning to guide the treatment.

Vasorelaxant effects of ellagitannins isolated from Cuphea carthagenensis.

Cuphea carthagenensis (Jacq.) J. F. Macbr. is a popular plant in Brazilian folk medicine owing to its hypotensive and central nervous system depressant effects. This study aimed to validate the hypotensive effect of the plant's aqueous extract (AE) in rats and examine the vascular actions of three hydrolyzable tannins, oenothein B, woodfordin C, and eucalbanin B, isolated from AE. Systolic blood pressure in unanesthetized rats was determined using the non-invasive tail-cuff method. Oral treatment of normotensive rats with 0.5 and 1.0 g/kg/day AE induced a dose-related hypotensive effect after 1 week. In rat aortic rings pre-contracted with noradrenaline, all ellagitannins (20 - 180 µM) induced a concentration-related vasorelaxation. This effect was blocked by either removing the endothelium or pre-incubating with NG-nitro-l-arginine methyl ester (10 µM), an inhibitor of nitric oxide (NO) synthase. In KCl-depolarized rat portal vein preparations, the investigated compounds did not affect significantly the maximal contractile responses and pD2 values of the concentration-response curves to CaCl2. Our results demonstrated the hypotensive effect of C. carthagenensis AE in unanesthetized rats. All isolated ellagitannins induced vasorelaxation in vitro via activating NO synthesis/NO release from endothelial cells, without altering the Ca2+ influx in vascular smooth muscle preparations. Considering the low oral bioavailability of ellagitannins, the determined in vitro actions of these compounds are unlikely to account for the hypotensive effect of AE in vivo. It remains to be determined the role of the bioactive ellagitannin-derived metabolites in the hypotensive effect observed after oral treatment of unanesthetized rats with the plant extract.

Use total portosystemic shunt to rescue an emergency PNF with intractable hypotension: A case report.

RATIONALE: Living donor allogeneic liver transplantation is a surgical treatment for patients with end-stage liver disease, wherein a healthy liver is implanted in the patient, facilitating the recovery of the liver function in patients with end-stage liver disease. However, primary nonfunction (PNF) may occur as a result of this procedure. PATIENT CONCERNS: A case of an 65-year-old Asian male with a medical history of cirrhosis and hepatocellular carcinoma is described. Intractable hypotension occurred after open hepatic portal anastomosis, and large doses of vasoactive substances did not improve the condition. DIAGNOSIS: PNF was diagnosed during surgery and it caused intractable hypotension. INTERVENTIONS: we promptly used the total portosystemic shunt to achieve a successful rescue. OUTCOMES: The strengthening of perioperative management and active treatment allowed second liver transplantation and anhepatic phase of up to 10 hours, following which the patient was rescued. LESSONS: The lesson we have learned is that total portosystemic shunt composited with careful anesthesia management can rescue the event of PNF with intractable hypotension in liver transplantation surgery. At the same time, we give attention to blood pressure, electrocardiogram, albumin, calcium, potassium, acidosis, coagulopathy, anti-infection, and protection of vital organs is essential for successful retransplant outcomes.

Efficacy of Low Dose Intravenous Epinephrine Infusion in Improving Perioperative Outcomes in Patients Undergoing Transurethral Resection of Prostate: A Prospective Parallel Arm Double-Blind Randomized Control Trial.

OBJECTIVE: To determine the efficacy of intraoperative low-dose intravenous epinephrine infusion in improving intraoperative bleeding and perioperative outcomes of transurethral resection of prostate (TURP) surgery. METHODS: This was a double-blinded, randomized control trial in which all patients undergoing bipolar TURP were included. Patients with uncontrolled hypertension, cardiac disease, and on anticoagulants were excluded. The study group received intravenous epinephrine, whereas the control group received normal saline at the same rate (0.05 µg/kg/min) throughout the procedure. Intraoperative blood loss was the primary outcome. The secondary outcomes were incidence of intraoperative hypotension (due to spinal anesthesia), resection time, indwelling catheter time, and length of hospitalization. RESULTS: Thirty-six patients were included in each group. Demographic and clinical profiles were comparable with an overall median prostate size of 41 (34-52) gram in both groups. The primary objective, mean intraoperative blood loss in the study group was lower than the control group but statistically insignificant (67.91+/-18.7 mL vs 75.14 +/-17.1 mL; P = .086). Incidence of intraoperative hypotension was significantly lower in the study group (8.3% vs 33.3%; P = .01). Rest of the secondary outcomes, resection time (83 (64-111.5) minutes vs 86 (68-94.75) minutes; P = .97), mean indwelling catheter time (P = .94), postoperative complications (P = .73), and length of hospitalization (P = .87) were comparable. CONCLUSION: In this first-of-its-kind trial, low-dose epinephrine infusion did not reduce intraoperative blood loss in patients undergoing TURP. However, it significantly reduced intraoperative hypotension, which complicates spinal anesthesia particularly in elderly population.

The Hypotensive and Vasodilatory Effects Observed in Rats Exposed to Chiranthodendron pentadactylon Larreat Flowers Can Be Attributed to Cyanidin 3-O-Glucoside.

Chiranthodendron pentadactylon Larreat is a tree native to southeastern Mexico and Guatemala. Its flower is used in Mexican folk medicine to treat a variety of diseases, including conditions of blood pressure. However, scientific information on its usefulness in this pathology is lacking. The present study evaluates the effect of a methanolic extract (ME) from the flower and its active constituents on heart rate (HR) and mean arterial pressure (MAP) in anesthetized rats (MAPHR). The study also analyzed the effects on rat-isolated aortic rings (RIAR) and the rat mesenteric arterial bed (MABR). Active fractions were chromatographed, which led to the isolation of cyanidin 3-O-glucoside (C3G) identified through HPLC. The Chiranthodendron pentadactylon flowers produced hypotensive and vasorelaxant effects associated with C3G. The vasorelaxant effect is a mechanism underlying the synthesis and release of nitric oxide (NO). Neither cholinergic receptors nor prostaglandins are involved. ME and C3G cause cardiovascular depression in anesthetized rats via cholinergic and prostanoid mechanisms. Our research expands the scientific understanding of the flowers on the rat cardiovascular system. This amplifies the appreciation of the flower's ethnomedicine employed to control blood pressure. However, researchers need to conduct toxicity studies to determine the safety of this plant.

Treatment of postprandial hypotension with acarbose in an adult with cervical spinal cord injury: a case report.

INTRODUCTION: Postprandial hypotension is a type of autonomic dysfunction where there is a decrease in systolic blood pressure of >20 mm HG within 2 h after eating thought to be due to poor cardiovascular compensation for splanchnic blood pooling that occurs with meals. This form of autonomic dysfunction is underdiagnosed in patients with spinal cord injury, likely in part because it can be asymptomatic. CASE PRESENTATION: 26-year-old with complete cervical spinal cord injury (SCI) presented with neck pain described as severe 10/10 pain, which felt like "a rope around his neck." Pain came on during and after meals and was associated with a feeling of pressure behind his eyes, white spots in his vision along with feeling as if he was going to pass out. The caregiver noted a systolic blood pressure drop by about 30-40 points with meals and lost weight due to avoiding eating. A diagnosis of post-prandial hypotension (PPH) was made and Acarbose was started at a low dose 25 mg three times per day with meals. During follow up, the patient reported complete resolution of drops of blood pressure, neck pain, and all associated symptoms. The patient was able to eat comfortably and gained weight. DISCUSSION: There are few case reports on PPH in SCI and none looking at acarbose on a young, nondiabetic person with SCI. Clinicians should be aware that PPH can occur in young otherwise healthy people with SCI. Further research is needed on PPH, including the use of acarbose, in the SCI population.

Vitamins and Minerals for Blood Pressure Reduction in the General, Normotensive Population: A Systematic Review and Meta-Analysis of Six Supplements.

Hypertension is the leading preventable risk factor for cardiovascular disease and all-cause mortality worldwide. However, studies have shown increased risk of mortality from heart disease and stroke even within the normal blood pressure (BP) range, starting at BPs above 110-115/70-75 mm Hg. Nutraceuticals, such as vitamins and minerals, have been studied extensively for their efficacy in lowering BP and may be of benefit to the general, normotensive population in achieving optimal BP. Our study investigated the effects of six nutraceuticals (Vitamins: C, D, E; Minerals: Calcium, Magnesium, Potassium) on both systolic blood pressure (SBP) and diastolic blood pressure (DBP) in this population. We performed a systematic review and pairwise meta-analysis for all six supplements versus placebo. Calcium and magnesium achieved significant reductions in both SBP and DBP of -1.37/-1.63 mm Hg and -2.79/-1.56 mm Hg, respectively. Vitamin E and potassium only yielded significant reductions in SBP with values of -1.76 mm Hg and -2.10 mm Hg, respectively. Vitamins C and D were not found to significantly lower either SBP or DBP. Future studies should determine optimal dosage and treatment length for these supplements in the general, normotensive population.

Insulin concentrations following termination of high-dose insulin euglycemic therapy.

INTRODUCTION: High-dose insulin therapy is used in patients with calcium channel blocker and beta-adrenergic antagonist overdoses. The pharmacokinetics of insulin are scantly reported following high-dose insulin therapy. We present two cases of persistently elevated insulin concentrations following high-dose insulin therapy. CASE REPORTS: A 50-year-old woman and a 45-year-old man experienced hypotension after overdosing on amlodipine and atenolol. They were treated with high-dose insulin therapy for 54 hours at 2 units/kilogram/hour and 48 hours at 10 units/kilogram/hour, respectively. Following termination, serum insulin elimination was studied. Insulin concentrations remained greater than 1,000 µU/mL (fasting reference 2.6-24.9 µU/mL) for longer than 4 hours (case 1) and 11 hours (case 2) and greater than 300 µU/mL for longer than 8 hours and 21 hours, respectively. Insulin concentrations decreased with apparent first-order elimination half-lives of 13.0 hours and 6.0 hours. DISCUSSION: Following high-dose insulin therapy, insulin concentrations remained elevated for longer than expected based on normal pharmacokinetics in therapeutic dosing. Three previous cases reported insulin half-lives of between 2.2 hours and 18.7 hours. The current cases add to the existing data that insulin has a variable but prolonged half-life following high-dose insulin therapy. CONCLUSIONS: These findings suggest that patients are at prolonged risk of hypoglycemia following cessation of high-dose insulin infusions.

Interactions between Mediterranean Diet Supplemented with Dairy Foods and the Gut Microbiota Influence Cardiovascular Health in an Australian Population.

The impact of a Mediterranean diet on the intestinal microbiome has been linked to its health benefits. We aim to evaluate the effects of a Mediterranean diet supplemented with dairy foods on the gut microbiome in Australians at risk of cardiovascular disease. In a randomised controlled cross-over study, 34 adults with a systolic blood pressure ≥120 mmHg and with risk factors for cardiovascular disease were randomly allocated to a Mediterranean diet with 3-4 daily serves of dairy foods (Australian recommended daily intake (RDI) of 1000-1300 mg per day (MedDairy)) or a low-fat (LFD) control diet. Between each 8-week diet, participants underwent an 8-week washout period. Microbiota characteristics of stool samples collected at the start and end of each diet period were determined by 16S rRNA amplicon sequencing. MedDairy-associated effects on bacterial relative abundance were correlated with clinical, anthropometric, and cognitive outcomes. No change in the overall faecal microbial structure or composition was observed with either diet (p > 0.05). The MedDairy diet was associated with changes in the relative abundance of several bacterial taxa, including an increase in Butyricicoccus and a decrease in Colinsella and Veillonella (p < 0.05). Increases in Butyricicoccus relative abundance over 8 weeks were inversely correlated with lower systolic blood pressure (r = -0.38, p = 0.026) and positively correlated with changes in fasting glucose levels (r = 0.39, p = 0.019), specifically for the MedDairy group. No significant associations were observed between the altered taxa and anthropometric or cognitive measures (p > 0.05). Compared to a low-fat control diet, the MedDairy diet resulted in changes in the abundance of specific gut bacteria, which were associated with clinical outcomes in adults at risk of CVD.

Paralysis under pressure.

Treating cardiovascular paralysis with epidural electrical neuromodulation.

Melatonin supplementation reduces nighttime blood pressure but does not affect blood pressure reactivity in normotensive adults on a high-sodium diet.

High-sodium diets (HSDs) can cause exaggerated increases in blood pressure (BP) during physiological perturbations that cause sympathetic activation, which is related to cardiovascular risk. Melatonin supplementation has been shown to play a role in BP regulation. Our aim was to examine the effects of melatonin taken during an HSD on 24-h BP and BP reactivity during isometric handgrip (IHG) exercise, postexercise ischemia (PEI), and the cold pressor test (CPT). Twenty-two participants (11 men/11 women, 26.5 ± 3.1 yr, BMI: 24.1 ± 1.8 kg/m2, BP: 111 ± 9/67 ± 7 mmHg) were randomized to a 10-day HSD (6,900 mg sodium/day) that was supplemented with either 10 mg/day of melatonin (HSD + MEL) or placebo (HSD + PL). Twenty-four-hour ambulatory BP monitoring was assessed starting on day 9. Mean arterial pressure (MAP) was quantified during the last 30 s of IHG at 40% of maximal voluntary contraction and CPT, and during 3 min of PEI. Melatonin did not change 24-h MAP (HSD + PL: 83 ± 6 mmHg; HSD + MEL: 82 ± 5 mmHg; P = 0.23) but decreased nighttime peripheral (HSD + PL: 105 ± 10 mmHg; HSD + MEL: 100 ± 10 mmHg; P = 0.01) and central systolic BP (HSD + PL: 97 ± 9 mmHg; HSD + MEL: 93 ± 8 mmHg; P = 0.04) on the HSD compared with the HSD + PL. The absolute and percent change in MAP during IHG was not different between conditions (all P > 0.05). In conclusion, melatonin supplementation did not alter BP reactivity to the perturbations tested on an HSD but may be beneficial in lowering BP in young healthy normotensive adults.NEW & NOTEWORTHY BP reactivity was assessed during isometric handgrip (IHG) exercise, postexercise ischemia (PEI), and the cold pressor test (CPT) after 10 days of a high-sodium diet with and without melatonin supplementation. Melatonin did not alter BP reactivity in healthy normotensive men and women. However, melatonin did decrease nighttime peripheral and central systolic BP, suggesting it may be beneficial in lowering BP even in those with a normal BP.

Efficacy of beetroot juice on reducing blood pressure in hypertensive adults with autosomal dominant polycystic kidney disease (BEET-PKD): study protocol for a double-blind, randomised, placebo-controlled trial.

BACKGROUND: In autosomal dominant polycystic kidney disease (ADPKD) impaired nitric oxide (NO) synthesis, in part, contributes to early-onset hypertension. Beetroot juice (BRJ) reduces blood pressure (BP) by increasing NO-mediated vasodilation. The aim of this double-blind, randomised, placebo-controlled study is to test the hypothesis that BRJ reduces systolic and diastolic clinic BP in hypertensive adults with ADPKD. METHODS: Participants with ADPKD and treated hypertension (n = 60) will be randomly allocated (1:1) to receive a daily dose of either nitrate-replete (400 mg nitrate/day) or nitrate-deplete BRJ for 4 weeks. The co-primary outcomes are change in mean systolic and diastolic clinic BP before and after 4 weeks of treatment with daily BRJ. Secondary outcomes are changes in daily home BP, urinary albumin to creatinine ratio, serum and salivary nitrate/nitrite levels and serum asymmetric dimethylarginine levels before and after 4 weeks of BRJ. DISCUSSION: The effect of BRJ in ADPKD has not been previously tested. BRJ is an accessible, natural dietary supplement that, if effective, will provide a novel adjunctive approach for treating hypertension in ADPKD. TRIAL REGISTRATION: ClinicalTrials.gov NCT05401409. Retrospectively registered on 27th May 2022.

[Emergent Transcatheter Aortic Valve Implantation for Degenerated Surgical Aortic Valve Under Local Anesthesia:Report of a Case].

An 89-year-old man who had undergone aortic valve replacement with a 21 mm Mosaic bioprosthetic valve at another hospital 14 years ago was admitted to the emergency room for a sudden respiratory distress two days prior and was diagnosed with severe aortic regurgitation( AR) caused by valve insufficiency and acute heart failure secondary to low cardiac function. Upon admission, he was found to have severe hypoxia with PaO2 of 40 mmHg range, and transcatheter aortic valve replacement (TAVI, TAV in SAV) with a 20 mm SAPIEN3 was performed under local anesthesia for fear of hypotension while under general anesthesia. After confirming that AR had completely disappeared, the patient was intubated and discharged from the operating room on a mechanical ventilator. The patient was weaned from the ventilator on the second postoperative day and was transferred to the other hospital for rehabilitation, 48 days postoperatively. Although there is no report on the comparative study of anesthesia methods for emergency transcatheter aortic valve implantation( TAVI), TAVI under regional anesthesia is minimally invasive with a lower risk for hypotension than general anesthesia. Therefore, we believe it is useful for patients with acute heart failure and hypotension. In addition, it is important to use a balloon expandable valve with excellent implantability to complete the procedure in a short time.

Reduction in blood pressure following acute dietary nitrate ingestion is correlated with increased red blood cell S-nitrosothiol concentrations.

Dietary nitrate (NO3-) supplementation can enhance nitric oxide (NO) bioavailability and lower blood pressure (BP) in humans. The nitrite concentration ([NO2-]) in the plasma is the most commonly used biomarker of increased NO availability. However, it is unknown to what extent changes in other NO congeners, such as S-nitrosothiols (RSNOs), and in other blood components, such as red blood cells (RBC), also contribute to the BP lowering effects of dietary NO3-. We investigated the correlations between changes in NO biomarkers in different blood compartments and changes in BP variables following acute NO3- ingestion. Resting BP was measured and blood samples were collected at baseline, and at 1, 2, 3, 4 and 24 h following acute beetroot juice (∼12.8 mmol NO3-, ∼11 mg NO3-/kg) ingestion in 20 healthy volunteers. Spearman rank correlation coefficients were determined between the peak individual increases in NO biomarkers (NO3-, NO2-, RSNOs) in plasma, RBC and whole blood, and corresponding decreases in resting BP variables. No significant correlation was observed between increased plasma [NO2-] and reduced BP, but increased RBC [NO2-] was correlated with decreased systolic BP (rs = -0.50, P = 0.03). Notably, increased RBC [RSNOs] was significantly correlated with decreases in systolic (rs = -0.68, P = 0.001), diastolic (rs = -0.59, P = 0.008) and mean arterial pressure (rs = -0.64, P = 0.003). Fisher's z transformation indicated no difference in the strength of the correlations between increases in RBC [NO2-] or [RSNOs] and decreased systolic blood pressure. In conclusion, increased RBC [RSNOs] may be an important mediator of the reduction in resting BP observed following dietary NO3- supplementation.

Blood Pressure Changes in Association with Nimodipine Therapy in Patients with Spontaneous Subarachnoid Hemorrhage.

BACKGROUND: Nimodipine is recommended to prevent delayed cerebral ischemia in patients with spontaneous subarachnoid hemorrhage (SAH). Here, we studied hemodynamic side effects of different nimodipine formulations (per os [PO] and intravenous [IV]) in patients with SAH undergoing continuous blood pressure monitoring. METHODS: This observational cohort study includes consecutive patients with SAH (271 included in the IV group, 49 in the PO group) admitted to a tertiary care center between 2010 and 2021. All patients received prophylactic IV or PO nimodipine. Hemodynamic responses were evaluated based on median values within the first hour after continuous IV nimodipine initiation or PO nimodipine application (601 intakes within 15 days). Significant changes were defined as > 10% drop in systolic blood pressure (SBP) or diastolic blood pressure from baseline (median values 30 min before nimodipine application). With the use of multivariable logistic regression, risk factors associated with SBP drops were identified. RESULTS: Patients were admitted with a median Hunt & Hess score of 3 (2-5; IV 3 [2-5], PO 1 [1-2], p < 0.001) and were 58 (49-69) years of age. Initiation of IV nimodipine was associated with a > 10% SBP drop in 30% (81/271) of patients, with a maximum effect after 15 min. A start or increase in noradrenaline was necessary in 136/271 (50%) patients, and colloids were administered in 25/271 (9%) patients within 1 h after IV nimodipine initiation. SBP drops > 10% occurred after 53/601 (9%) PO nimodipine intakes, with a maximum effect after 30-45 min in 28/49 (57%) patients. Noradrenaline application was uncommon (3% before and 4% after nimodipine PO intake). Hypotensive episodes to an SBP < 90 mm Hg were not observed after IV or PO nimodipine application. In multivariable analysis, only a higher SBP at baseline was associated with a > 10% drop in SBP after IV (p < 0.001) or PO (p = 0.001) nimodipine application, after adjusting for the Hunt & Hess score on admission, age, sex, mechanical ventilation, days after intensive care unit admission, and delayed cerebral ischemia. CONCLUSIONS: Significant drops in SBP occur in one third of patients after the start of IV nimodipine and after every tenth PO intake. Early recognition and counteracting with vasopressors or fluids seems necessary to prevent hypotensive episodes.