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Biosensors & Bioelectronics Sep 2023Since the heart pumps out the blood through the excitation-contraction coupling, simultaneous monitoring of the electrical and mechanical characteristics is beneficial...
Since the heart pumps out the blood through the excitation-contraction coupling, simultaneous monitoring of the electrical and mechanical characteristics is beneficial for comprehensive diagnosis of cardiac disorders. Currently, these characteristics are monitored separately with electrocardiogram (ECG) and medical imaging techniques. This work presents a fully implantable device named mechano-electrocardiogram (MECG) sensor that can measure mechanocardiogram (MCG) and ECG together. The key to the success is fabrication of permeable electrodes on a single low-modulus porous nanofiber mat, which helps immediate adhesion of the sensor on the tissue. A strain-insensitive electrode is used as the ECG electrode and a strain-sensitive electrode is used for MCG. The MECG device is implanted subcutaneously in the skin above the heart of the rat. Through a vasopressor (phenylephrine) injection test, the MECG signals indicate that the MCG amplitude is related with blood pressure and the ECG peak interval is more related with heart rate. These results confirm that the MECG device is clinically meaningful for continuous and comprehensive monitoring of the electrical and mechanical characteristics of the heart.
Topics: Rats; Animals; Biosensing Techniques; Heart; Electrocardiography; Heart Rate; Prostheses and Implants
PubMed: 37276637
DOI: 10.1016/j.bios.2023.115443 -
Surgical Endoscopy Aug 2023Although it is known that excessive intraoperative fluid and vasopressor agents are detrimental for anastomotic healing, optimal anesthesiology protocols for colorectal... (Observational Study)
Observational Study
BACKGROUND
Although it is known that excessive intraoperative fluid and vasopressor agents are detrimental for anastomotic healing, optimal anesthesiology protocols for colorectal surgery are currently lacking.
OBJECTIVE
To scrutinize the current hemodynamic practice and vasopressor use and their relation to colorectal anastomotic leakage.
DESIGN
A secondary analysis of a previously published prospective observational study: the LekCheck study.
STUDY SETTING
Adult patients undergoing a colorectal resection with the creation of a primary anastomosis.
OUTCOME MEASURES
Colorectal anastomotic leakage (CAL) within 30 days postoperatively, hospital length of stay and 30-day mortality.
RESULTS
Of the 1548 patients, 579 (37%) received vasopressor agents during surgery. Of these, 201 were treated with solely noradrenaline, 349 were treated with phenylephrine, and 29 received ephedrine. CAL rate significantly differed between the patients receiving vasopressor agents during surgery compared to patients without (11.8% vs 6.3%, p < 0.001). CAL was significantly higher in the group receiving phenylephrine compared to noradrenaline (14.3% vs 6%, p < 0.001). Vasopressor agents were used more often in patients treated with Goal Directed Therapy (47% vs 34.6%, p < 0.001). There was a higher mortality rate in patients with vasopressors compared to the group without (2.8% vs 0.4%, p = 0.01, OR 3.8). Mortality was higher in the noradrenaline group compared to the phenylephrine and those without vasopressors (5% vs. 0.4% and 1.7%, respectively, p < 0.001). In multivariable analysis, patients with intraoperative vasopressor agents had an increased risk to develop CAL (OR 2.1, CI 1.3-3.2, p = 0.001).
CONCLUSION
The present study contributes to the evidence that intraoperative use of vasopressor agents is associated with a higher rate of CAL. This study helps to create awareness on the (necessity to) use of vasopressor agents in colorectal surgery patients in striving for successful anastomotic wound healing. Future research will be required to balance vasopressor agent dosage in view of colorectal anastomotic leakage.
Topics: Adult; Humans; Anastomotic Leak; Colorectal Surgery; Risk Factors; Vasoconstrictor Agents; Anastomosis, Surgical; Phenylephrine; Norepinephrine; Colorectal Neoplasms
PubMed: 37126191
DOI: 10.1007/s00464-023-09980-1 -
The Medical Letter on Drugs and... Jun 2024
Topics: Humans; Mydriasis; Phentolamine; Ophthalmic Solutions; Mydriatics; Administration, Ophthalmic
PubMed: 38905525
DOI: 10.58347/tml.2024.1705c -
American Journal of Perinatology May 2024Mydriatic eye drops used for retinopathy of prematurity (ROP) examination can cause systemic effects, and there are case reports of serious adverse effects in the...
OBJECTIVE
Mydriatic eye drops used for retinopathy of prematurity (ROP) examination can cause systemic effects, and there are case reports of serious adverse effects in the literature. In this prospective study, we aimed to evaluate the early hemodynamic effects of mydriatic eye drops to understand the possible mechanisms of adverse effects.
STUDY DESIGN
Between December 2018 and March 2019, preterm babies less than 32 gestational weeks and who underwent ophthalmologic examination in our unit were included. The vital signs (heart rate, respiratory rate, oxygen saturation [SpO], and blood pressure values), cerebral and mesenteric tissue saturation by near-infrared spectroscopy (NIRS), and left ventricular functions of infants were recorded before and after applying mydriatic eye drops (2.5% phenylephrine and 0.5% tropicamide). The data were compared statistically. Strict adherence to prevent systemic absorption of the eye drops was applied.
RESULTS
Thirty-two mydriasis procedures were evaluated in 26 patients. The mean gestational age was 28.5 ± 1.7 weeks, and the mean birth weight was 943 ± 233 g. There were no significant differences in terms of vital signs of infants including heart rate, blood pressure, and oxygen saturation [SpO] levels before and after eye-drop application. In addition, NIRS values showed no significant differences between before and after measurements. No significant differences were detected at echocardiographic evaluation performed before and after mydriatic administration. No adverse reaction was observed in the study population during the study.
CONCLUSION
This is the first study that evaluated the early hemodynamic effects of mydriatic eye drops used for ROP screening by vital signs, NIRS, and echocardiographic evaluation. Mydriatic eye drops have no significant effect on early hemodynamic parameters including vital signs, NIRS, and echocardiographic findings in preterm infants. We suggest that a cautious approach for avoiding the systemic absorption of these agents may prevent the possible early systemic effects in this high-risk population.
KEY POINTS
· Mydriatic eye drops are commonly used for pupil dilatation before retinopathy of prematurity examination, and there are reports of serious adverse events caused by these drops.. · Due to the adverse events of eye drops, hemodynamic effects of these agents were investigated by clinical findings, near-infrared spectroscopy, and echocardiography.. · No significant early hemodynamic effect was observed so avoiding systemic effects may be prevented with precautions..
Topics: Humans; Mydriatics; Infant, Newborn; Ophthalmic Solutions; Prospective Studies; Female; Male; Infant, Premature; Tropicamide; Hemodynamics; Retinopathy of Prematurity; Phenylephrine; Spectroscopy, Near-Infrared; Gestational Age; Heart Rate; Oxygen Saturation; Blood Pressure
PubMed: 35714652
DOI: 10.1055/a-1877-7868 -
International Journal of Molecular... Dec 2023Cardiac hypertrophy resulting from sympathetic nervous system activation triggers the development of heart failure. The transcription factor Y-box binding protein 1...
Cardiac hypertrophy resulting from sympathetic nervous system activation triggers the development of heart failure. The transcription factor Y-box binding protein 1 (YB-1) can interact with transcription factors involved in cardiac hypertrophy and may thereby interfere with the hypertrophy growth process. Therefore, the question arises as to whether YB-1 influences cardiomyocyte hypertrophy and might thereby influence the development of heart failure. YB-1 expression is downregulated in human heart biopsies of patients with ischemic cardiomyopathy ( = 8), leading to heart failure. To study the impact of reduced YB-1 in cardiac cells, we performed small interfering RNA (siRNA) experiments in H9C2 cells as well as in adult cardiomyocytes (CMs) of rats. The specificity of YB-1 siRNA was analyzed by a miRNA-like off-target prediction assay identifying potential genes. Testing three high-scoring genes by transfecting cardiac cells with YB-1 siRNA did not result in downregulation of these genes in contrast to , whose downregulation increased hypertrophic growth. Hypertrophic growth was mediated by PI3K under PE stimulation, as well by downregulation with YB-1 siRNA. On the other hand, overexpression of in CMs, caused by infection with an adenovirus encoding (AdYB-1), prevented hypertrophic growth under α-adrenergic stimulation with phenylephrine (PE), but not under stimulation with growth differentiation factor 15 (GDF15; = 10-16). An adenovirus encoding the green fluorescent protein (AdGFP) served as the control. overexpression enhanced the mRNA expression of the Gq inhibitor regulator of G-protein signaling 2 () under PE stimulation ( = 6), potentially explaining its inhibitory effect on PE-induced hypertrophic growth. This study shows that YB-1 protects cardiomyocytes against PE-induced hypertrophic growth. Like in human end-stage heart failure, YB-1 downregulation may cause the heart to lose its protection against hypertrophic stimuli and progress to heart failure. Therefore, the transcription factor YB-1 is a pivotal signaling molecule, providing perspectives for therapeutic approaches.
Topics: Adult; Humans; Animals; Rats; Adrenergic Agents; Phenylephrine; Heart Failure; Myocytes, Cardiac; RNA, Small Interfering; Adenoviridae; Cardiomegaly; Transcription Factors
PubMed: 38203580
DOI: 10.3390/ijms25010401 -
Frontiers in Pharmacology 2023The prostate gland is surrounded by periprostatic adipose tissue (PPAT) that can release mediators that interfere in prostate function. In this study, we examined the...
Periprostatic adipose tissue (PPAT) supernatant from obese mice releases anticontractile substances and increases human prostate epithelial cell proliferation: the role of nitric oxide and adenosine.
The prostate gland is surrounded by periprostatic adipose tissue (PPAT) that can release mediators that interfere in prostate function. In this study, we examined the effect of periprostatic adipose tissue supernatant obtained from obese mice on prostate reactivity and on the viability of human prostatic epithelial cell lines. Male C57BL/6 mice were fed a standard or high-fat diet after which PPAT was isolated, incubated in Krebs-Henseleit solution for 30 min (without prostate) or 60 min (with prostate), and the supernatant was then collected and screened for biological activity. Total nitrate and nitrite (NOx) and adenosine were quantified, and the supernatant was then collected and screened for biological activity. NOx and adenosine were quantified. Concentration-response curves to phenylephrine (PE) were obtained in prostatic tissue from lean and obese mice incubated with or without periprostatic adipose tissue. In some experiments, periprostatic adipose tissue was co-incubated with inhibitors of the nitric oxide (NO)-cyclic guanosine monophosphate pathway (L-NAME, 1400W, ODQ), adenylate cyclase (SQ22536) or with adenosine A (ZM241385), and A (MRS1754) receptor antagonists. PNT1-A (normal) and BPH-1 (hyperplasic) human epithelial cells were cultured and incubated with supernatant from periprostatic adipose tissue for 24, 48, or 72 h in the absence or presence of these inhibitors/antagonists, after which cell viability and proliferation were assessed. The levels of NOx and adenosine were significantly higher in the periprostatic adipose tissue supernatant (30 min, without prostate) when compared to the vehicle. A trend toward an increase in the levels of NOX was observed after 60 min. PPAT supernatant from obese mice significantly reduced the PE-induced contractions only in prostate from obese mice. The co-incubation of periprostatic adipose tissue with L-NAME, 1400W, ODQ, or ZM241385 attenuated the anticontractile activity of the periprostatic adipose tissue supernatant. Incubation with the supernatant of periprostatic adipose tissue from obese mice significantly increased the viability of PNT1-A cells and attenuated expression of the apoptosis marker protein caspase-3 when compared to cells incubated with periprostatic adipose tissue from lean mice. Hyperplastic cells (BPH-1) incubated with periprostatic adipose tissue from obese mice showed greater proliferation after 24 h, 48 h, and 72 h compared to cells incubated with culture medium alone. BPH-1 cell proliferation in the presence of PPAT supernatant was attenuated by NO-signaling pathway inhibitors and by adenosine receptor antagonists after 72 h. NO and adenosine are involved in the anticontractile and pro-proliferative activities of periprostatic adipose tissue supernatant from obese mice. More studies are needed to determine whether the blockade of NO and/or adenosine derived from periprostatic adipose tissue can improve prostate function.
PubMed: 37492091
DOI: 10.3389/fphar.2023.1145860 -
JAMA Mar 2024
Topics: Commerce; Phenylephrine; Pseudoephedrine; United States
PubMed: 38329748
DOI: 10.1001/jama.2023.27932 -
Scientific Reports Apr 2024Although the esophageal stethoscope is used for continuous auscultation during general anesthesia, few studies have investigated phonocardiographic data as a continuous...
Although the esophageal stethoscope is used for continuous auscultation during general anesthesia, few studies have investigated phonocardiographic data as a continuous hemodynamic index. In this study, we aimed to induce hemodynamic variations and clarify the relationship between the heart sounds and hemodynamic variables through an experimental animal study. Changes in the cardiac contractility and vascular resistance were induced in anesthetized pigs by administering dobutamine, esmolol, phenylephrine, and nicardipine. In addition, a decrease in cardiac output was induced by restricting the venous return by clamping the inferior vena cava (IVC). The relationship between the hemodynamic changes and changes in the heart sound indices was analyzed. Experimental data from eight pigs were analyzed. The mean values of the correlation coefficients of changes in S1 amplitude (ΔS1amp) with systolic blood pressure (ΔSBP), pulse pressure (ΔPP), and ΔdP/dt during dobutamine administration were 0.94, 0.96, and 0.96, respectively. The mean values of the correlation coefficients of ΔS1amp with ΔSBP, ΔPP, and ΔdP/dt during esmolol administration were 0.80, 0.82, and 0.86, respectively. The hemodynamic changes caused by the administration of phenylephrine and nicardipine did not correlate significantly with changes in the heart rate. The S1 amplitude of the heart sound was significantly correlated with the hemodynamic changes caused by the changes in cardiac contractility but not with the variations in the vascular resistance. Heart sounds can potentially provide a non-invasive monitoring method to differentiate the cause of hemodynamic variations.
Topics: Animals; Swine; Heart Sounds; Dobutamine; Nicardipine; Hemodynamics; Phenylephrine; Propanolamines
PubMed: 38615106
DOI: 10.1038/s41598-024-59362-3 -
The Journal of Neuroscience : the... Feb 2024Cardiovascular homeostasis is maintained, in part, by neural signals arising from arterial baroreceptors that apprise the brain of blood volume and pressure. Here, we...
Cardiovascular homeostasis is maintained, in part, by neural signals arising from arterial baroreceptors that apprise the brain of blood volume and pressure. Here, we test whether neurons within the nodose ganglia that express angiotensin type-1a receptors (referred to as NG) serve as baroreceptors that differentially influence blood pressure (BP) in male and female mice. Using -Cre mice and Cre-dependent AAVs to direct tdTomato to NG, neuroanatomical studies revealed that NG receive input from the aortic arch, project to the caudal nucleus of the solitary tract (NTS), and synthesize mechanosensitive ion channels, To evaluate the functionality of NG, we directed the fluorescent calcium indicator (GCaMP6s) or the light-sensitive channelrhodopsin-2 (ChR2) to -containing neurons. Two-photon intravital imaging in -GCaMP6s mice revealed that NG couple their firing to elevated BP, induced by phenylephrine (i.v.). Furthermore, optical excitation of NG at their soma or axon terminals within the caudal NTS of -ChR2 mice elicited robust frequency-dependent decreases in BP and heart rate, indicating that NG are sufficient to elicit appropriate compensatory responses to vascular mechanosensation. Optical excitation also elicited hypotensive and bradycardic responses in ChR2-expressing mice that were subjected to deoxycorticosterone acetate (DOCA)-salt hypertension; however, the duration of these effects was altered, suggestive of hypertension-induced impairment of the baroreflex. Similarly, increased GCaMP6s fluorescence observed after administration of phenylephrine was delayed in mice subjected to DOCA-salt or chronic delivery of angiotensin II. Collectively, these results reveal the structure and function of NG and suggest that such neurons may be exploited to discern and relieve hypertension.
Topics: Mice; Male; Female; Animals; Desoxycorticosterone Acetate; Hypertension; Solitary Nucleus; Sensory Receptor Cells; Blood Pressure; Phenylephrine; Ion Channels; Red Fluorescent Protein
PubMed: 38242697
DOI: 10.1523/JNEUROSCI.1154-23.2023 -
Indian Journal of Ophthalmology Jul 2024To study the pupil dynamics with premixed intracameral anesthetic mydriatic combination of phenylephrine (0.31%), tropicamide (0.02%), and lidocaine (1%) in pediatric...
PURPOSE
To study the pupil dynamics with premixed intracameral anesthetic mydriatic combination of phenylephrine (0.31%), tropicamide (0.02%), and lidocaine (1%) in pediatric cataract surgery.
METHODS
Consecutive children aged ≤12 years planned for cataract surgery were recruited. A commercially available premixed combination of phenylephrine (0.31%), tropicamide (0.02%), and lidocaine (1%) was injected at the beginning of surgery without any topical/infusion drugs for mydriasis. Pupil sizes at various points of surgery were studied.
RESULTS
We recruited 75 patients with a mean age of 24.3 ± 33.4 months (range: 1 month-11 years). Adequate mydriasis with a single injection was achieved in 93.5% (n = 73 eyes of 70 patients) without additional pharmacotherapy or intervention. The mean pupillary diameter increased from 1.8 ± 0.79 to 6.1 ± 1.4 mm after injection (mean change of 4.2 ± 1.25 mm from baseline). The mean variability in pupillary diameter was 0.73 ± 1.3 mm. In five eyes, good dilatation was not possible even after repeat injection.
CONCLUSION
Fixed-dose premixed intracameral injection is effective in pupil dilatation. It alleviates the need for any topical dilators or additional intraoperative supplementation for pediatric cataract surgery.
Topics: Humans; Mydriatics; Child, Preschool; Male; Infant; Female; Cataract Extraction; Pupil; Child; Tropicamide; Phenylephrine; Lidocaine; Anterior Chamber; Cataract; Prospective Studies; Follow-Up Studies; Ophthalmic Solutions; Dose-Response Relationship, Drug
PubMed: 38454863
DOI: 10.4103/IJO.IJO_2628_23