Rapid cardiovascular effects of dexamethasone in rabbits with meconium-induced acute lung injury

2008 ◽  
Vol 86 (11) ◽  
pp. 804-814 ◽  
Author(s):  
Daniela Mokra ◽  
Ingrid Tonhajzerova ◽  
Juraj Mokry ◽  
Anna Drgova ◽  
Maria Petraskova ◽  
...  

Glucocorticoids may improve lung function in newborns with meconium aspiration syndrome (MAS), but information on the acute side effects of glucocorticoids in infants is limited. In this study using a rabbit model of MAS, we addressed the hypothesis that systemic administration of dexamethasone causes acute cardiovascular changes. Adult rabbits were treated with 2 intravenous doses of dexamethasone (0.5 mg/kg each) or saline at 0.5 h and 2.5 h after intratracheal instillation of human meconium or saline. Animals were oxygen-ventilated for 5 h after the first dose of treatment. Blood pressure, heart rate, and short-term heart rate variability (HRV) were analyzed during treatment, for 5 min immediately after each dose, and for the 5 h of the experiment. In the meconium-instilled animals, dexamethasone increased blood pressure, decreased heart rate, increased HRV parameters, and caused cardiac arrhythmia during and immediately after administration. In the saline-instilled animals, the effect of dexamethasone was inconsistent. In these animals, the acute effects of dexamethasone on blood pressure and cardiac rhythm were reversed after 30 min, whereas heart rate continued to decrease and HRV parameters continued to increase for 5 h after the first dose of dexamethasone. These effects were more pronounced in meconium-instilled animals. If systemic glucocorticoids are used in the treatment of MAS, cardiovascular side effects of glucocorticoids should be considered.

2008 ◽  
Vol 60 (2) ◽  
pp. 329-334 ◽  
Author(s):  
R.L. Linardi ◽  
J.C. Canola ◽  
C.A.A. Valadão

Cardiovascular effects due to intravenous (IV) xylazine (1.0mg/kg) or amitraz (0.1 or 0.4mg/kg) were evaluated in horses. Left ventricular function indexes, heart rate (HR), and cardiac output (CO) were measured by echocardiography. Second degree atrioventricular (AV) block was detected by electrocardiography. Invasive arterial blood pressure (AP) was also evaluated. All parameters were measured immediately before and during 60 minutes after drug injection. HR, CO, and second degree AV block were different between xylazine and amitraz-0.4mg/kg groups. Xylazine induced initial hypertension 10 minutes after injection, and hypotension was observed 30 minutes after amitraz-0.4mg/kg administration. Except for the second degree AV block which occurred only at five minutes, there was no change in the echocardiographic measurements after administration of amitraz-0.1mg/kg. Thus, amitraz-0.4mg/kg and xylazine (1.0mg/kg) induced similar cardiovascular side effects, but long-lasting action of amitraz-0.4mg/kg in the cardiovascular system was observed.


1980 ◽  
Vol 59 (s6) ◽  
pp. 235s-237s ◽  
Author(s):  
R. W. Rockhold ◽  
J. T. Crofton ◽  
L. Share

1. The cardiovascular effects of an enkephalin analogue were examined in spontaneously hypertensive and normotensive Wistar-Kyoto rats. (D-Ala2)-methionine enkephalin caused a biphasic increase in blood pressure and an increase in heart rate after intracerebroventricular injection. 2. The initial pressor response to (D-Ala2)-methionine enkephalin was greater in hypertensive than in normotensive rats. No difference was noted between groups during the secondary pressor response. Heart rate increases paralleled the secondary increase in blood pressure. 3. Naloxone pretreatment abolished the secondary increase in blood pressure and the tachycardia, but did not blunt the initial pressor response in female Wistar-Kyoto rats. 4. Plasma levels of arginine vasopressin were depressed during the plateau phase of the pressor response in hypertensive rats given intracerebroventricular (d-Ala2)-methionine enkephalin. 5. The results suggest that the cardiovascular effects of central enkephalin are not due to vasopressin, but may involve activation of the sympathetic nervous system.


2021 ◽  
pp. 1-7
Author(s):  
Tércio A.R. Barros ◽  
Wagner L. do Prado ◽  
Thiago R.S. Tenório ◽  
Raphael M. Ritti-Dias ◽  
Antônio H. Germano-Soares ◽  
...  

This study compared the effects of self-selected exercise intensity (SEI) versus predetermined exercise intensity (PEI) on blood pressure (BP) and arterial stiffness in adolescents with obesity. A total of 37 adolescents, 14.7 (1.6) years old, body mass index ≥95th percentile were randomly allocated into SEI (n = 18; 12 boys) or PEI (n = 19; 13 boys). Both groups exercised for 35 minutes on a treadmill, 3 times per week, for 12 weeks. The SEI could set the speed at the beginning of the sessions and make changes every 5 minutes. The PEI adolescents were trained at an intensity set at 60% to 70% of heart rate reserve. Brachial and central BP, pulse pressure, augmentation index, and carotid–femoral pulse wave were determined at baseline and after 12 weeks. Both groups reduced brachial systolic BP (SEI, Δ = −9 mm Hg; PEI, Δ = −4 mm Hg; P < .01), central systolic BP (SEI, Δ = −4 mm Hg; PEI, Δ = −4 mm Hg; P = .01), and central pulse pressure (SEI, Δ = −4 mm Hg; PEI, Δ = −3 mm Hg; P = .02) without differences between groups. No changes in the augmentation index and carotid–femoral pulse wave were observed in either group. The SEI induced similar changes in various cardiovascular outcomes compared with PEI in adolescents with obesity.


Author(s):  
G.F. Stegmann

In humans the combined administration of epidural anaesthesia and inhalation anaesthesia may result in cardiovascular instability associated with decreases in heart rate and blood pressure. Anaesthesia was induced with a combination of midazolam / ketamine in 18 female pigs with a mean body weight of 24.9±5.9 kg scheduled for surgical removal of the liver. After tracheal intubation, anaesthesia was maintained on a circle rebreathing circuit with isoflurane. Epidural anaesthesia was administered with ropivacaine (AL-group, n=8) at 0.2 mℓ / kg of a 7.5 mg / mℓ solution to the anaesthetised animals. The A-group (n = 10) received isoflurane anaesthesia only. The vaporiser was set at 2.5 % for the A-group and 1.5 % for the AL-group. Heart rate, invasive systolic, diastolic, and mean arterial blood pressure were monitored. Comparisons were made between treatments and within treatments comparing variables during surgical preparation and abdominal surgery. Differences between treatments were not statistically significant (P > 0.05) during surgical preparation or during abdominal surgery. For within treatment groups, the differences between surgical preparation and abdominal surgery were statistically significant (P < 0.05) for heart rate in the A-group, but not statistically significant (P > 0.05) for the other variables. It is concluded that abdominal surgery may be associated with statistically significant changes in heart rate in isoflurane-anaesthetised pigs and that the combined administration of epidural ropivacaine may prevent statistically significant changes in HR during abdominal surgery.


2016 ◽  
Vol 29 (3) ◽  
pp. 543-552
Author(s):  
João Douglas Alves ◽  
Jorge Luiz de Brito Gomes ◽  
Caio Victor Coutinho de Oliveira ◽  
José Victor de Miranda Henriques Alves ◽  
Fabiana Ranielle de Siqueira Nogueira ◽  
...  

Abstract Introduction: Tai-Chi-Chuan and Yoga have becoming popular practices. However is unclear the cardiovascular effects, and if they present similar behavior to aerobic and resistance sessions. Objective: To evaluate the cardiovascular responses during the session and post-exercise hypotension (PEH) of Tai Chi Chuan (TS) and Yoga (YS) in comparison to aerobic (AS) and resistance (SR) exercises. Methods: Fourteen young women (22.3 ± 2 years) apparently healthy performed four sessions (AS, RS, TS and YS). The heart rate (HR), systolic (SBP) and diastolic blood pressure (DBP) were recorded at resting, during (every 10 minutes) and until 50 minutes of recovery. Results: AS, RS, TS e YS showed significant increase in HR compared to resting.AS at 10, 30 e 50 minutes in relation to RS, TS e YS. The RS in relation to TS and YS at 10, 30 and 50 minutes. No significant difference between TS and YS. SBP was significantly increased in AS, RS, TS e YS at 10, 30 e 50 minutes during the session, in relation to rest. AS was significantly higher at 30 e 50 minutes than RS and higher than TS and YS at 10, 30 e 50 minutes. No significant difference in DBP. For PEH, AS, RS and TS significantly reduced at 10, 30 and 50 minutes. YS reduced at 50 minutes. No significant diastolic PEH. Conclusion: TS and YS showed as safe alternatives of exercising in the normotensive young adult woman, despite having lower values, they promote similar hemodynamic behavior to AS and RS.


2011 ◽  
Vol 51 (5) ◽  
pp. 282
Author(s):  
Tjhin Wiguna ◽  
Sasanto Wibisono ◽  
Sudigdo Sastroasmoro ◽  
Fransiscus D. Suyatna

Objective To identify the cardiovascular effects of long-acting methylphenidate administered for twelve weeks in Indonesian children with ADHD.Methods This was an 18-week, time series study on children with ADHD who were given 20 mg of long-acting methylphenidate for twelve weeks. During the study period we made ten serial observations of the subjects, including before, during and 6 weeks following drug administration. We included drug naive children with ADHD between the ages of 7 – 10 years. Children with mental retardation and chronic physical or mental disorders were excluded. Blood pressure was measured by sphygmomanometer with a child’s cuff at the brachial artery. We also collected data on heart rate, side effects, complaints and other medications used during the study. Repeated analysis was performed on the data with a P level of 0.05.Results Twenty-one subjects were recruited for this study. Mean blood pressure fluctuated insignificantly during the research period, for both mean systolic and mean diastolic blood pressures (P=0.115 and P=0.059). Mean heart rate also fluctuated insignificantly (P=0.091). All fluctuations were within the normal ranges. During the study, there were complaints of dizziness, nausea, and gastrointestinal upset, but they were reportedly mild and disappeared before the second week of observation.Conclusion Administration of 20 mg long-acting methylphenidate for twelve weeks in children with ADHD altered mean blood pressures and heart rates, but within the normal range for children of their age. However, cardiovascular risk observation is still needed when administering methylphenidate to children with ADHD, especially for those using the medication long-term.[Paediatr Indones. 2011;51:282-7].


2018 ◽  
Vol 23 (6) ◽  
pp. 473-478
Author(s):  
Raymond P. Meddock ◽  
Deirdre Bloemer

OBJECTIVES Neonatal abstinence syndrome (NAS) is characterized by withdrawal symptoms in neonates exposed to legal or illegal substances in utero, and it is often managed with medications such as opiates, phenobarbital, and clonidine. Clonidine use is increasing, but further safety data regarding its use in neonates are warranted. This study evaluated the effects of clonidine on heart rate and blood pressure in neonates treated for NAS at doses up to 24 mcg/kg/day. METHODS A retrospective review via the electronic medical record of infants at least 35 weeks' gestation treated adjunctively with clonidine for NAS in the neonatal intensive care unit at St Elizabeth was conducted. Heart rate, and systolic and diastolic blood pressure were recorded at baseline, while on different dose ranges of clonidine (small: ≤1.5 mcg/kg per dose every 3 hours; medium: &gt;1.5 to 2 mcg/kg per dose every 3 hours; and large: &gt;2 mcg/kg to 3 mcg/kg per dose every 3 hours), and upon discontinuation. RESULTS A total of 64 infants treated with clonidine for NAS between August 2015 and December 2016 were included. Heart rate decreased in all clonidine dose ranges compared with baseline (average reduction of 7 bpm [CI: −12 to −2], 9 bpm [CI: −16 to −2], and 10 bpm [CI: −18 to −1] for the small, medium, and large dose ranges, respectively; p &lt; 0.0001). Systolic and diastolic blood pressure were not significantly different from baseline when infants were receiving any dose of clonidine, except diastolic blood pressure while on medium–dose range clonidine, where diastolic blood pressure was higher than baseline (p = 0.0128). Increases in systolic and diastolic blood pressure were evident upon discontinuation of clonidine (p &lt; 0.0001 and p = 0.0156, respectively). CONCLUSIONS Clonidine doses up to 24 mcg/kg/day are well tolerated in neonates ≥35 weeks' gestation treated for NAS. Any decreases in heart rate are likely clinically insignificant, and increases in blood pressure upon discontinuing clonidine are mild and may be mitigated further with extended discontinuation protocols. Further trials should be conducted to evaluate the long-term safety of clonidine in this population.


Author(s):  
Josef Niebauer ◽  
Carl Johan Sundberg

The abuse of doping substances is prevalent in sports and in society at large. Doping substances are also present in a substantial fraction of nutritional supplements. They can cause severe side effects. This chapter is focused on cardiovascular side effects. Androgenic anabolic steroids can induce left ventricular hypertrophy, heart fibrosis, and systolic and diastolic dysfunction, and has been associated with dyslipidaemia, endothelial dysfunction, and coronary artery disease. Beta-2 agonists can induce chronotropic and inotropic effects, QT prolongation, palpitations, arrhythmias and sudden cardiac death. Erythropoietin can induce hypertension and embolism. Use of banned substances and methods in sports, i.e. doping, is prohibited, unethical, and dangerous. Research efforts in sports sciences and sports medicine are needed to prevent and treat doping abuse and to help athletes be successful without the need for doping.


Author(s):  
G.F. Stegmann

The cardiovascular effects of non-abdominal and abdominal surgery during isoflurane anaesthesia (A-group) or isoflurane anaesthesia supplemented with either epidural ropivacaine (AR-group; 0.75 % solution, 0.2 mℓ/kg) or morphine (AM-group; 0.1 mg/kg diluted in saline to 0.2mℓ/kg) were evaluated in 28 healthy pigs with a mean body weight of 30.3 kg SD ± 4.1 during surgical devascularisation of the liver. Anaesthesia was induced with the intramuscular injection of midazolam (0.3 mg/kg) and ketamine (10 mg/kg). Anaesthesia was deepened with intravenous propofol to enable tracheal intubation and maintained with isoflurane on a circle rebreathing circuit. The vaporiser was set at 2.5% for the A-group and 1.5% for the AR- and AM-groups. Differences between treatment groups were not statistically significant (P>0.05) for any of the variables. Differences between AM- and AR-groups were marginally significant heart rate (HR) (P = 0.06) and mean arterial blood pressure (MAP) (P = 0.08). Within treatment groups, differences for the A-group were statistically significant (P<0.05) between non-abdominal and abdominal surgery for HR, systolic blood pressure, diastolic blood pressure (DIA) and MAP. Within the AM-group differences were statistically significant (P < 0.05) for DIA and MAP, and within the AR group differences for all variables were not statistically significant (P > 0.05). It was concluded that in isoflurane-anaesthetised pigs, the epidural administration of ropivacaine decreased heart rate and improved arterial blood pressure during surgery.


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
A S Antonopoulos ◽  
G Skotsimara ◽  
E Oikonomou ◽  
N Ioakeimidis ◽  
C V Mistakidi ◽  
...  

Abstract Background Electronic cigarette (EC) is marketed as a safe alternative to tobacco smoking, but EC cardiovascular effects remains largely unknown. Purpose To systematically review and meta-analyse published literature to investigate the cardiovascular effects and associated risk from EC use. Methods We searched PubMed from January 2000 until November 2017 for published studies assessing the cardiovascular effects of EC. For each eligible study we used the mean difference (MD) with 95% confidence intervals (CIs) for SBP, DBP and HR. The pooled MDs for each outcome of interest were calculated by using a fixed effects model. The presence of heterogeneity among studies was evaluated by the I2 statistic. Results We report conflicting evidence on the effects of EC on heart rate and blood pressure, which is mainly based on non-randomized clinical studies of moderate quality. In a meta-analysis of 14 studies (n=441 participants), that despite the negative effects of EC on heart rate (pooled MD=2.27, 95% CI: 1.64 to 2.89, p<0.001), diastolic (DBP, pooled MD=2.01mmHg, 95% CI: 0.62 to 3.39, p=0.004) and systolic blood pressure (SBP, pooled MD=2.02mmHg, 95% CI: 0.07 to 3.97, p=0.042), benefits may be observed in terms of blood pressure regulation when switching from tobacco smoking to EC (SBP pooled MD=−7.00, 95% CI: −9.63 to −4.37, p<0.001; DBP pooled MD=−3.65, 95% CI: −5.71 to −1.59, p=0.001). Evidence suggests that EC negatively affects endothelial function, arterial stiffness and the long-term risk for coronary events, but these findings are derived from single study reports and have not been confirmed in additional studies. Conclusions We report adverse effects of EC use on heart rate and blood pressure. Unless supported by stronger evidence, EC should not be labelled as cardiovascular safe products. Future studies should delineate whether EC use is less hazardous to cardiovascular health than conventional cigarette smoking.


Sign in / Sign up

Export Citation Format

Share Document