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Journal of Vascular Surgery Cases and... Dec 2023We present a case of medication-induced priapism that was refractory to conventional urologic methods and required treatment with a caverno-saphenous bypass. The patient...
We present a case of medication-induced priapism that was refractory to conventional urologic methods and required treatment with a caverno-saphenous bypass. The patient had been misusing an injectable erectile dysfunction medication consisting of alprostadil, papaverine, and phentolamine (Trimix), resulting in multiple episodes of priapism. His initial episodes of priapism were successfully treated with the traditional urologic algorithm, including phenylephrine, aspiration, and distal shunting. However, due to his continued medication misuse, these became ineffective, requiring proximal shunt surgery. Priapism requiring an extra-anatomic bypass is exceedingly rare. Following our proximal shunt surgery, he maintained partial sexual function, and his bypass remained patent.
PubMed: 38106342
DOI: 10.1016/j.jvscit.2023.101359 -
Arquivos Brasileiros de Oftalmologia 2023Cycloplegia is crucial for reliable pediatric ophthalmology examinations. This document provides a re-commendation for pediatric cycloplegia and mydriasis for Brazilian...
Cycloplegia is crucial for reliable pediatric ophthalmology examinations. This document provides a re-commendation for pediatric cycloplegia and mydriasis for Brazilian ophthalmologists. This article was developed based on literature reviews; the clinical experience of Brazilian specialists, as obtained through questionnaires; and the consensus of the Expert Committee of the Brazilian Pediatric Ophthalmology Society. According to the best evidence and formulations available in Brazil, this committee recommends the use of one drop of 1% cyclopentolate plus one drop of 1% tropicamide in children older than 6 months and two drops of 1% tropicamide 0-5 minutes apart for those younger than 6 months. Mydriasis may be increased by a single drop of 2.5% phenylephrine. For retinopathy of prematurity screening, the recommendation is 0.5% or 1% tropicamide, administered two or three times, 5 minutes apart, and 2.5% phenylephrine, used preferably once. In all scenarios, we recommend the use of a prior drop of 0.5% proxymetacaine.
PubMed: 35319660
DOI: 10.5935/0004-2749.20230049 -
Annals of Anatomy = Anatomischer... Jun 2024A reliable estimation of time since death can be important for the law enforcement authorities. The compound method encompassing supravital reactions such as the...
BACKGROUND
A reliable estimation of time since death can be important for the law enforcement authorities. The compound method encompassing supravital reactions such as the chemical excitability of the iris can be used to further narrow intervals estimated by temperature-based methods. Postmortem iris excitability was mostly assessed by parasympatholytic or parasympathomimetic substances. Little is known regarding sympathomimetic agents. The present study aims to describe the postmortem iris excitability using the sympathomimetic drug phenylephrine.
METHODS
Cadavers were included after body donors gave written informed consent during lifetime. Exclusion criteria were known eye disease, or a postmortem interval exceeding 26 hours. A pupillometer with a minimum measurement range of 0.5 mm was used to determine the horizontal pupil diameter before and 20 minutes after the application of phenylephrine. Increase in pupil diameter was labeled as positive reaction, unchanged pupil diameter was labeled as negative reaction, and decrease in pupil diameter was labeled as paradox reaction.
RESULTS
30 eyes from 16 cadavers (median age = 80.0; 9 males, 7 females) were examined. Initial pupil size was in median 3.5 mm (interquartile range [IQR]: 3.0-4.5 mm) and progressed to 4.0 mm (IQR: 3.5-5.0 mm) 20 minutes after drug instillation. The achieved pupil diameter difference comprised in median 0.5 mm (IQR: 0.0-1.0 mm). A positive reaction was observed in 21 cases. Negative reactions were observed in 5 cases and paradox reactions in 4 cases. Overall, there was a statistically significant difference in diameter between the initial and the reactive pupil (P = 0.0002).
CONCLUSION
Although relatively rarely used, sympathomimetic drugs seem to be eligible for chemical postmortem iris excitability. Currently, assessment of postmortem iris excitability usually only involves parasympatholytic and parasympathomimetic agents. The findings of the present study give a hint that the application of a third agent with a sympathomimetic mechanism of action could provide additional information. Further studies assessing such a triple approach in the compound method in comparison with the current gold standard for estimation of time since death are mandatory to ensure reliable results.
Topics: Humans; Male; Female; Iris; Phenylephrine; Postmortem Changes; Pupil; Aged, 80 and over; Cadaver; Aged; Sympathomimetics
PubMed: 38460860
DOI: 10.1016/j.aanat.2024.152240 -
Journal of Dental Anesthesia and Pain... Dec 2023This review paper delves into the comparative study of epinephrine and phenylephrine as vasoconstrictors in dental anesthesia, exploring their histories, pharmacological... (Review)
Review
This review paper delves into the comparative study of epinephrine and phenylephrine as vasoconstrictors in dental anesthesia, exploring their histories, pharmacological properties, and clinical applications. The study involved a comprehensive literature search, focusing on articles that directly compared the two agents in terms of efficacy, safety, and prevalence in dental anesthesia. Epinephrine, with its broad receptor profile, has been a predominant choice, slightly outperforming in the context of prolonging dental anesthesia and providing superior hemostasis, which is crucial for various dental procedures. However, the stimulation of beta-adrenergic receptors caused by epinephrine poses risks, especially to patients with cardiovascular conditions. Phenylephrine, a selective alpha-1 adrenergic agonist, emerges as a safer alternative for such patients, avoiding the cardiovascular risks associated with epinephrine. Moreover, its vasoconstrictive effect may not be as deleterious as that of epinephrine, due to its selective action. This review reveals that despite the potential benefits of phenylephrine, epinephrine continues to dominate in clinical settings, due to its historical familiarity, availability, and cost-effectiveness. The lack of commercially available pre-made phenylephrine dental carpules in most countries, except Brazil, and a knowledge gap within dental academia regarding phenylephrine, contribute to its limited use. This review concludes that while both agents are effective, the choice between them should be based on individual patient conditions, availability, and the practitioner's knowledge and familiarity with the agents. The underuse of other vasoconstrictors like levonordefrin and the unavailability of phenylephrine in pre-mixed dental cartridges in many countries highlights the need for further exploration and research in this field. Furthermore, we also delve into the role of levonordefrin and examine the rationale behind the exclusion of phenylephrine from commercially available pre-mixed local anesthetic carpules, suggesting a need for a responsive approach from pharmaceutical manufacturers to the distinct needs of the dental community.
PubMed: 38076507
DOI: 10.17245/jdapm.2023.23.6.293 -
American Journal of Veterinary Research Nov 2023To elucidate the cardiovascular effects of escalating doses of phenylephrine and norepinephrine in dogs receiving acepromazine and isoflurane.
OBJECTIVE
To elucidate the cardiovascular effects of escalating doses of phenylephrine and norepinephrine in dogs receiving acepromazine and isoflurane.
ANIMALS
8 beagles aged 1 to 2 years (7.4 to 11.2 kg).
METHODS
All dogs received acepromazine 0.01 mg/kg, propofol 4 to 5 mg/kg, and isoflurane and were mechanically ventilated. Mean arterial pressure (MAP) from a femoral artery catheter and continuous electrocardiogram were recorded. Cardiac output (CO) was measured with transpulmonary thermodilution. Systemic vascular resistance (SVR), global end-diastolic volume (GEDV), and global ejection fraction (GEF) were subsequently calculated. Phenylephrine and norepinephrine were infused in random order at 0.07, 0.3, 0.7, and 1.0 μg/kg/min. All variables were measured after 15 minutes of each infusion rate. The effects of dose, agent, and their interaction on the change of each variable were evaluated with mixed-effect models. A P < .05 was used for significance.
RESULTS
Atrial premature complexes occurred in 3 dogs during norepinephrine infusion at doses of 0.3, 0.7, and 1 μg/kg/min; no dysrhythmias were seen with phenylephrine administration. MAP increased during dose escalation (P < .0001) within each agent and did not differ between agents (P = .6). The decrease in HR was greater for phenylephrine (P < .0001). Phenylephrine decreased CO and GEF and increased GEDV and SVR (all P < .03). Norepinephrine decreased the SVR and increased CO, GEDV, and GEF (all P < .03).
CLINICAL RELEVANCE
Our results confirm that phenylephrine increases arterial pressures mainly through vasoconstriction in acepromazine-premedicated dogs while norepinephrine, historically considered a vasopressor, does so primarily through an increase in inotropism.
Topics: Animals; Dogs; Acepromazine; Isoflurane; Norepinephrine; Phenylephrine; Blood Pressure
PubMed: 37657733
DOI: 10.2460/ajvr.23.06.0147 -
Journal of Cellular and Molecular... Sep 2023Previous studies have reported that visfatin can regulate macrophage polarisation, which has been demonstrated to participate in cardiac remodelling. The aims of this...
Previous studies have reported that visfatin can regulate macrophage polarisation, which has been demonstrated to participate in cardiac remodelling. The aims of this study were to investigate whether visfatin participates in transverse aortic constriction (TAC)-induced cardiac remodelling by regulating macrophage polarisation. First, TAC surgery and angiotensin II (Ang II) infusion were used to establish a mouse cardiac remodelling model, visfatin expression was measured, and the results showed that TAC surgery or Ang II infusion increased visfatin expression in the serum and heart in mice, and phenylephrine or hydrogen peroxide promoted the release of visfatin from macrophages in vitro. All these effects were dose-dependently reduced by superoxide dismutase. Second, visfatin was administered to TAC mice to observe the effects of visfatin on cardiac remodelling. We found that visfatin increased the cross-sectional area of cardiomyocytes, aggravated cardiac fibrosis, exacerbated cardiac dysfunction, further regulated macrophage polarisation and aggravated oxidative stress in TAC mice. Finally, macrophages were depleted in TAC mice to investigate whether macrophages mediate the regulatory effect of visfatin on cardiac remodelling, and the results showed that the aggravating effects of visfatin on oxidative stress and cardiac remodelling were abrogated. Our study suggests that visfatin enhances cardiac remodelling by promoting macrophage polarisation and enhancing oxidative stress. Visfatin may be a potential target for the prevention and treatment of clinical cardiac remodelling.
Topics: Mice; Animals; Ventricular Remodeling; Nicotinamide Phosphoribosyltransferase; Constriction; Myocytes, Cardiac; Aortic Valve Stenosis; Macrophages; Oxidative Stress; Angiotensin II; Mice, Inbred C57BL; Fibrosis; Cardiomegaly
PubMed: 37584247
DOI: 10.1111/jcmm.17854 -
International Journal of Molecular... Sep 2023Our previous studies revealed the protection of stachydrine hydrochloride (STA) against cardiopathological remodeling. One of the underlying mechanisms involves the...
Our previous studies revealed the protection of stachydrine hydrochloride (STA) against cardiopathological remodeling. One of the underlying mechanisms involves the calcium/calmodulin-dependent protein kinase Ⅱ (CaMKII). However, the way STA influences CaMKII needs to be further investigated. The nicotinamide adenine dinucleotide phosphate oxidase 2 (NOX2)-coupled reactive oxygen species (ROS) overproduction putatively induces the oxidative activation of CaMKII, resulting in the occurrence of pathological cardiac remodeling and dysfunction in experimental models of mice. Thus, in this study, we assessed the role of the NOX2-ROS signal axis in STA cardioprotection. The transverse aortic constriction (TAC)-induced heart failure model of mice, the phenylephrine-induced hypertrophic model of neonatal rat primary cardiomyocytes, and the HO-induced oxidative stress models of adult mouse primary cardiomyocytes and H9c2 cells were employed. The echocardiography and histological staining were applied to assess the cardiac effect of STA (6 mg/kg/d or 12 mg/kg/d), which was given by gavage. NOX2, ROS, and excitation-contraction (EC) coupling were detected by Western blotting, immunofluorescence, and calcium transient-contraction synchronous recordings. ROS and ROS-dependent cardiac fibrosis were alleviated in STA-treated TAC mice, demonstrating improved left ventricular ejection fraction and hypertrophy. In the heart failure model of mice and the hypertrophic model of cardiomyocytes, STA depressed NOX2 protein expression and activation, as shown by inhibited translocation of its phosphorylation, p67phox and p47phox, from the cytoplasm to the cell membrane. Furthermore, in cardiomyocytes under oxidative stress, STA suppressed NOX2-related cytosolic Ca overload, enhanced cell contractility, and decreased Ca-dependent regulatory protein expression, including CaMKⅡ and Ryanodine receptor calcium release channels. Cardioprotection of STA against pressure overload-induced pathological cardiac remodeling correlates with the NOX2-coupled ROS signaling cascade.
Topics: Animals; Rats; Reactive Oxygen Species; Calcium; Calcium-Calmodulin-Dependent Protein Kinase Type 2; Hydrogen Peroxide; Stroke Volume; Ventricular Remodeling; Ventricular Function, Left; Heart Failure; Hypertrophy; Myocytes, Cardiac; Aortic Valve Stenosis; Calcium, Dietary
PubMed: 37762672
DOI: 10.3390/ijms241814369 -
Journal of Clinical Medicine Oct 2023The purpose of this study is to evaluate choroidal thickness (ChT) at the subfoveal and peripheral level after the instillation of 0.5% tropicamide + 10% phenylephrine 9...
The purpose of this study is to evaluate choroidal thickness (ChT) at the subfoveal and peripheral level after the instillation of 0.5% tropicamide + 10% phenylephrine 9 hydrochloride eye drops by using OCT scans in enhanced depth image (EDI) mode. In total, 53 patients (30 males and 23 females) were involved, and the mean age was 25.62 ± 2.41 (age range: 23-36). The dominant eye was treated with tropicamide + phenylephrine (Visumidriatic Fenil 100 mg/mL + 5 mg/mL, Visufarma) while the nondominant eye was used as the control. An OCT analysis was performed on both eyes before and 30 min after the instillation of a drop of mydriatic in the dominant eye. The ChT was measured by using the OCT software measurement tool (Spectralis; Heidelberg Engineering; Heidelberg, Germany, version 6.0). The results showed a statistically significant ChT decrease ( = 0.009) in the temporal sector after the treatment with tropicamide + phenylephrine. In the subfoveal and nasal sectors, no statistically significant ChT changes were detected ( = 0.94; = 0.85) following the administration of the mydriatic eye drops. The ChT thinning in the temporal sector following the instillation of the tropicamide + phenylephrine eye drops suggests that in the case of ChT studies, mydriatic administration should be avoided.
PubMed: 37834998
DOI: 10.3390/jcm12196355 -
Journal of the American Heart... Sep 2023Background Pathological cardiac hypertrophy is a major cause of heart failure morbidity. The complex mechanism of intermolecular interactions underlying the pathogenesis...
Background Pathological cardiac hypertrophy is a major cause of heart failure morbidity. The complex mechanism of intermolecular interactions underlying the pathogenesis of cardiac hypertrophy has led to a lack of development and application of therapeutic methods. Methods and Results Our study provides the first evidence that TRAF4, a member of the tumor necrosis factor receptor-associated factor (TRAF) family, acts as a promoter of cardiac hypertrophy. Here, Western blotting assays demonstrated that TRAF4 is upregulated in cardiac hypertrophy. Additionally, TRAF4 deletion inhibits the development of cardiac hypertrophy in a mouse model after transverse aortic constriction surgery, whereas its overexpression promotes phenylephrine stimulation-induced cardiomyocyte hypertrophy in primary neonatal rat cardiomyocytes. Mechanistically, RNA-seq analysis revealed that TRAF4 promoted the activation of the protein kinase B pathway during cardiac hypertrophy. Moreover, we found that inhibition of protein kinase B phosphorylation rescued the aggravated cardiomyocyte hypertrophic phenotypes caused by TRAF4 overexpression in phenylephrine-treated neonatal rat cardiomyocytes, suggesting that TRAF4 may regulate cardiac hypertrophy in a protein kinase B-dependent manner. Conclusions Our results revealed the regulatory function of TRAF4 in cardiac hypertrophy, which may provide new insights into developing therapeutic and preventive targets for this disease.
Topics: Mice; Animals; Rats; Proto-Oncogene Proteins c-akt; TNF Receptor-Associated Factor 4; Heart Failure; Phenylephrine; Cardiomegaly
PubMed: 37642020
DOI: 10.1161/JAHA.122.028185 -
Journal of Cerebral Blood Flow and... Jul 2023Noradrenaline (NA) release from locus coeruleus axons generates vascular contractile tone in arteriolar smooth muscle and contractile capillary pericytes. This tone...
Noradrenaline (NA) release from locus coeruleus axons generates vascular contractile tone in arteriolar smooth muscle and contractile capillary pericytes. This tone allows neuronal activity to evoke vasodilation that increases local cerebral blood flow (CBF). Much of the vascular resistance within the brain is located in capillaries and locus coeruleus axons have NA release sites closer to pericytes than to arterioles. In acute brain slices, NA contracted pericytes but did not raise the pericyte cytoplasmic Ca concentration, while the α agonist phenylephrine did not evoke contraction. Blocking α adrenergic receptors (αRs, which induce contraction by inhibiting cAMP production), greatly reduced the NA-evoked pericyte contraction, whereas stimulating αRs using xylazine (a sedative) or clonidine (an anti-hypertensive drug) evoked pericyte contraction. Noradrenaline-evoked pericyte contraction and capillary constriction are thus mediated via αRs. Consequently, αRs may not only modulate CBF in health and pathological conditions, but also contribute to CBF changes evoked by αR ligands administered in research, veterinary and clinical settings.
Topics: Pericytes; Locus Coeruleus; Capillaries; Norepinephrine; Receptors, Adrenergic, alpha-2; Axons
PubMed: 36688515
DOI: 10.1177/0271678X231152549