Effects of Perioperative Dexmedetomidine Infusion in Patients Undergoing Vascular Surgery 

1995 ◽  
Vol 82 (3) ◽  
pp. 620-633 ◽  
Author(s):  
P. Talke ◽  
J. Li ◽  
U. Jain ◽  
J. Leung ◽  
K. Drasner ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Vascular Surgery ◽  
Low Dose ◽  
Plasma Concentrations ◽  
Surgical Patients ◽  
High Dose ◽  
Hemodynamic Management ◽  
Myocardial Wall Motion ◽  
Medium Dose

Background Dexmedetomidine, a highly selective alpha 2-adrenergic agonist, increases perioperative hemodynamic stability in healthy patients but decreases blood pressure and heart rate. The goal of this study was to evaluate, in a preliminary manner, the hemodynamic effects of perioperatively administered dexmedetomidine in surgical patients at high risk for coronary artery disease. Methods Twenty-four vascular surgery patients received a continuous infusion of placebo or one of three doses of dexmedetomidine, targeting plasma concentrations of 0.15 ng/ml (low dose), 0.30 ng/ml (medium dose), or 0.45 ng/ml (high dose) from 1 h before induction of anesthesia until 48 h postoperatively. All patients received standardized anesthesia and hemodynamic management. Blood pressure, heart rate, and Holter ECG were monitored; additional monitoring included continuous 12-lead ECG preoperatively, anesthetic concentrations and myocardial wall motion (echocardiography) intraoperatively, and cardiac enzymes postoperatively. Results Preoperatively, there was a decrease in heart rate (low dose 11%, medium dose 5%, high dose 20%) and systolic blood pressure (low dose 3%, medium dose 12%, high dose 20%) in patients receiving dexmedetomidine. Intraoperatively, dexmedetomidine groups required more vasoactive medications to maintain hemodynamics within predetermined limits. Postoperatively, demedetomidine groups had less tachycardia (minutes/monitored hours) than the placebo group (placebo 23 min/h; low dose 9 min/h, P = 0.006; medium dose 0.5 min/h, P = 0.004; high dose 2.3 min/h, P = 0.004). Bradycardia was rare in all groups. There were no myocardial infarctions or discernible trends in the laboratory results. Conclusions Infusion of dexmedetomidine up to a targeted plasma concentration of 0.45 ng/ml appears to benefit perioperative hemodynamic management of surgical patients undergoing vascular surgery but required greater intraoperative pharmacologic intervention to support blood pressure and heart rate.

Sedative and physiologic effects of tiletamine–zolazepam following buccal administration in cats

2019 ◽  
Vol 22 (2) ◽  
pp. 108-113 ◽  
Author(s):  
Pablo Nejamkin ◽  
Verónica Cavilla ◽  
María Clausse ◽  
Florencia Landivar ◽  
Augusto M Lorenzutti ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Low Dose ◽  
Sedation Score ◽  
High Dose ◽  
Physiological Effects ◽  
Chemical Restraint ◽  
Hemoglobin Saturation ◽  
Baseline Systolic Blood Pressure ◽  
Over Time

Objectives The aim of this study was to describe the sedative and some physiological effects of tiletamine–zolazepam following buccal administration (BA) in cats. Methods Seven healthy spayed European shorthair cats (three males, four females) were studied twice in this randomized, blinded, crossover study. Each cat received two doses of tiletamine–zolazepam by BA: the low-dose (LD) group consisted of 5 mg/kg of each drug, and the high-dose (HD) group consisted of 7.5 mg/kg of each. Baseline systolic blood pressure (SAP), heart rate (HR), respiratory rate (RR) and a sedation score were recorded prior to administration of each treatment. The same variables plus the percentage of hemoglobin saturated with oxygen as measured by pulse oximetry (SpO2) were recorded at predefined intervals for the next 2 h. Results All cats completed the study. No retching or vomiting were observed. Hypersalivation was observed in 0/7 and 3/7 for LD and HD groups, respectively ( P = 0.2). There were significant changes in scores over time for posture, response to clippers and response to manual restraint for both groups, without differences between groups. RR, HR and SAP changed significantly over time. SAP and RR were significantly lower for the HD than for the LD group. No values for hemoglobin saturation <95% were observed. Conclusions and relevance BA of tiletamine–zolazepam at the doses studied here is a simple and effective method for chemical restraint in cats, where the LD group had a lower impact on SAP and RR than the HD group.

Fluid balance, electrolyte profiles and plasma parathyroid hormone concentrations in ewes treated with epidermal growth factor

1992 ◽  
Vol 135 (1) ◽  
pp. 91-101 ◽  
Author(s):  
C. B. Gow ◽  
M. Wilkinson ◽  
M. J. Silvapulle ◽  
G. P. M. Moore
Keyword(s):  
Parathyroid Hormone ◽  
Growth Factor ◽  
Fluid Balance ◽  
Low Dose ◽  
Plasma Concentrations ◽  
Urine Volume ◽  
High Dose ◽  
Epidermal Growth ◽  
Higher Doses ◽  
Medium Dose

ABSTRACT The infusion of low doses of epidermal growth factor (EGF) into lactating ewes stimulates water intake and urine volume. The plasma concentrations and daily output of various electrolytes in milk and urine are also affected. We have investigated this further by recording the effects of EGF infusion on fluid balance, electrolyte profiles and plasma concentrations of glucose and parathyroid hormone (PTH) in non-pregnant, non-lactating ewes. Twenty-four animals (n= 8 per group) received infusions of 100 ml saline/day into the jugular vein for 10 days (days 1–10) followed by EGF at a dose rate of either 1 (low dose), 5 (medium dose) or 10 (high dose) μg/kg liveweight per day in 100 ml saline for 5 days (days 11–15). All ewes then received an infusion of 100 ml saline/day for 10 days (days 16–25). Most plasma and urine samples had undetectable concentrations of EGF-immunoreactive material during the periods of saline infusion. During EGF infusion, the highest amounts of EGF infusate excreted in urine were 1·6, 5·9 and 5·6% for ewes in low, medium and high dose groups respectively. Water intake increased by 17% (0·5 kg), 88% (2·5 kg) and 89% (2·3 kg) and urine volume increased by 29% (0·5 kg), 108% (2·2 kg) and 134% (2·1 kg) for the three groups respectively. Fluid balance and feed intake were not affected by EGF infusion, but the output of faecal dry matter was reduced in ewes receiving the two higher doses of EGF. All levels of EGF resulted in hypocalcaemia, increased plasma PTH concentrations and hypermagnesaemia. There was no effect of EGF on plasma concentrations of K+ and glucose or on daily urinary excretion of K+ and Mg2+. The only response to the low dose was a reduced plasma concentration of Na+ and an increased daily urinary urate excretion. The two higher doses increased the daily urinary excretion of Na+, PO43− and urate, but had no effect on the respective concentrations in plasma. Urinary Ca2+ excretion was reduced only during infusion of the medium dose of EGF. The responses of most variables were similar during infusion of the medium and high doses of EGF. All three doses of EGF induced polydipsic and diuretic responses in ewes, and infusions of 5–10 μg EGF/kg liveweight per day affected renal excretion of Ca2+, Na+ and PO3−4. We interpret the responses of the kidney and plasma PTH concentrations as a means of maintaining the homeostasis of plasma profiles of electrolytes. Journal of Endocrinology (1992) 135, 91–101

Changes in the arterial blood pressure, heart rate and normal ECG parameters of rat after envenomation with Egyptian cobra (Naja haje) venom

1997 ◽  
Vol 16 (6) ◽  
pp. 327-333 ◽  
Author(s):  
Mohamed Alaa A Omran ◽  
Ismail M Abdel-Nabi
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Electrical Activity ◽  
Arterial Blood Pressure ◽  
Wave Amplitude ◽  
Low Dose ◽  
High Dose ◽  
T Wave ◽  
Arterial Blood ◽  
Naja Haje

1 The effect of Egyptian cobra (Naja haje) venom on the normal electrical activity of the cardiac muscles (ECG) and arterial blood pressure of envenomated rats were investigated in this study. 2 Rats were divided into three groups. The first group was injected im with saline and considered as control group. Rats of the second and third groups were injected IM with 0.02 μg and 0.04 μg cobra venom/ gim b.wt, respectively. 3 Mean blood pressure (MBP), heart rate (HR) and four different ECG parameters (PR and QT intervals, R and T wave amplitudes) were measured over 1 h following envenomation. 4 The low dose (0.02 μg/g) of N. haje venom caused hypotension accompanied by an increase in the HR, whereas hypertension and bradycardia developed after injection of the high dose (0.04 μg/g) of venom. 5 There was a decrease in the P-R interval after administration of the low dose and prolongation of it after the high dose. The Q-T interval and R-wave amplitude were significantly increased after injection of both doses. T-wave amplitude was significantly elevated only after injection of the high dose. 6 The present results indicate that the Egyptian cobra (N. haje) venom significantly alters the arterial blood pressure and ECG parameters of envenomated rats. This suggests that impairment of the electrical activity of cardiac muscle may be one of the reasons why victims of cobra bite die.

Pre-emptive Analgesia for Postoperative Pain Relief in Children – Role of Paracetamol

2009 ◽  
pp. 9-16
Author(s):  
Rubina Yasmin ◽  
AKM Akhtaruzzaman ◽  
Paresh Chandra Sarker ◽  
Neaz Ahmed ◽  
Ranadhir Kumar Kundu ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Postoperative Pain ◽  
Diclofenac Sodium ◽  
Total Duration ◽  
Pain Scale ◽  
Prospective Clinical Study ◽  
High Dose ◽  
Induction Of Anaesthesia

This prospective clinical study was carried out in the Dept. of Anaesthesia, Analgesia and Intensive Care Medicine, BSMMU, Dhaka, during the period of May 2003 to July 2003. The study was done to emphasize the importance of giving analgesics preemptively instead of waiting for the child to complain of pain and to produce smooth recovery after surgery by decreasing immediate postoperative pain in children by a simple, safe acceptable drug. The children scheduled for tonsillectomy under general anaesthesia were recruited in this study. The analgesic efficiency of rectal paracetamol in two doses, 25 mg/kg bodywt.(Gr-P25) and 50 mg/kg. bodywt. (Gr-P50) were compared with Diclofenac Sodium suppository 1mg/ kg body weight (Gr-D) given half an hour before induction of anaesthesia. Pain scoring was done by TPPPS (Toddler Pre-schooler postoperative pain scale). Heart rate and blood pressure were stable in Gr-P50 and Gr-D. Time of first demand of analgesic was delayed in Gr-P50 and Gr-D. Total paracetamol consumption in 24 hours was less in Gr-P50(181±14.25) and Gr-D (212±25) than Gr-P25(318± 26.39). Total duration of analgesia in Gr- P50 (657±9.94) mins. and in Gr- D(502±10.63) mins. and in Gr-P25(288±23.17) mins. Pre-emptive high dose rectal paracetamol appears to be more effective than diclofenac sodium suppository for postoperative analgesia in children undergoing tonsillectomy. Journal of BSA, Vol. 18, No. 1 & 2, 2005 p.9-16

scholarly journals An observational comparative study of different doses of azilsartan and with chlorthalidone combination in moderate hypertension

2019 ◽  
Vol 8 (2) ◽  
pp. 259
Author(s):  
Tamoghna Maiti ◽  
Sonai Mandal ◽  
Ratul Banerjee ◽  
Sourav Chakrabarty ◽  
Amrita Panda
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Antihypertensive Agents ◽  
Fixed Dose ◽  
High Dose ◽  
Hypertensive Patients ◽  
Medical College ◽  
Fda Approval ◽  
High Prevalence ◽  
Dose Combination

Background: High blood pressure (BP) is one of the significant non-communicable diseases that are of high prevalence in our country. Hypertension (HTN) is responsible cause of 57% of stroke and 24% of coronary heart disease deaths in India. Eight classes of medications are currently used in the treatment of hypertension. Azilsartan medoxomil is a newly added FDA approved drug to the ARB class of antihypertensive agents. azilsartan and chlorthalidone combination is also got the FDA approval. There is limited study in between these two groups regarding efficacy especially in rural Bengal.Methods: A prospective observational study was done in medicine OPD of Bankura Sammilani Medical College for twelve weeks with two groups that are azilsartan (80mg) and fixed dose combination of azilsartan (40mg) plus chlorthalidone (12.5mg) in the age group of 18 to 55years of moderate hypertensive patients. Change of heart rate was assessed as safety parameter.Results: It was found that both the group of drugs are very much effective in lowering blood pressure constantly in respect of both systolic and diastolic BP but azilsartan monotherapy in high dose reduce systolic blood pressure slightly high. Significant change of heart rate was not seen with both the groups.Conclusions: Both the group was effective as well as safe in hypertensive patients.

Abstract P242: Nicotinic Acetylcholine Receptor Subunit α7 is Protective Against Angiotensin II-induced Aneurysm and Hypertension

Hypertension ◽  
2017 ◽  
Vol 70 (suppl_1) ◽  
Author(s):  
Nayaab S Khan ◽  
Spyros Mavropoulos ◽  
Kaie Ojamaa
Keyword(s):  
Blood Pressure ◽  
Acetylcholine Receptor ◽  
Nicotinic Acetylcholine Receptor ◽  
Low Dose ◽  
Histological Analysis ◽  
Inflammatory Activity ◽  
High Dose ◽  
Ang Ii ◽  
Nicotinic Acetylcholine ◽  
Α7 Nachr

Alpha7 nicotinic acetylcholine receptor (α7 nAChR), an integral component of the cholinergic nervous system is known to mediate cholinergic anti-inflammatory activity in various disease models such as sepsis, stroke and neurocognitive disorders. We report for the first time that the α7 nAChR -/- deficient mouse serves as a novel model of hypertension and aneurysm formation. Seven month old male WT and α7 nAChR -/- mice weighing 28-33g were infused with low dose Ang II (350 ng/kg/min) or high dose (700 ng/kg/min) or vehicle for 15 days using mini-osmotic pumps (Alzet, model 2004) implanted subcutaneously. Blood pressure (BP) was recorded on day 0,3,7,10 and 14. Mice were euthanized on day 15. Heart and body weights were measured, histological analysis was performed on the aortas and immune profile of peripheral blood was analyzed by flow cytometry. High dose Ang II resulted in 70% mortality from aneurysm rupture in α7 nAChR -/- mice starting as early as the 4 th day of infusion. While cardiac hypertrophy was not observed, low dose Ang II resulted in a sharp rise in blood pressure in α7 nAChR -/- beginning on the 3 rd day to 167±3.7 mmHg compared to 138±3.3 mmHg in WT treated mice. On day14 of low dose treatment, BP in α7 nAChR -/- rose to 171±4.2 vs.135±3.1 in WT mice. No changes were observed in BP of untreated WT or α7 nAChR -/- animals. Histological analysis revealed high grade aneurysm in aortas of α7 nAChR -/- mice treated with low dose Ang II, demonstrating a prominent germinal center within the false lumen and fibrous desmoplastic stroma. Increased infiltration of CD11B + monocytes, and myeloperoxidase + stained neutrophils were observed in these aortas but not in the aortas of similarly treated WT mice. Flow cytometric analysis showed 27% ± 3.9 CD11B + /CD45 + circulating monocytes and 48% ± 0.8 Ly6G + /CD45 + neutrophils in α7 nAChR -/- vs. 19% ± 3 monocytes and 11.85% ± 2.9 neutrophils in WT mice. No differences in the levels of circulating immune cells were observed in untreated mice of either genotype. These data support a protective role of α7 nAChR in hypertension and aneurysm, potentially acting through its cholinergic anti-inflammatory activity. The α7 nAChR -/- mouse may serve as a new genetic model of aneurysm relevant in studies of the human disease.

scholarly journals Carbidopa for Afferent Baroreflex Failure in Familial Dysautonomia

Hypertension ◽  
2020 ◽  
Vol 76 (3) ◽  
pp. 724-731
Author(s):  
Lucy Norcliffe-Kaufmann ◽  
Jose-Alberto Palma ◽  
Jose Martinez ◽  
Horacio Kaufmann
Keyword(s):  
Blood Pressure ◽  
Blood Pressure Variability ◽  
Low Dose ◽  
Familial Dysautonomia ◽  
Reduce Blood Pressure ◽  
Catecholamine Release ◽  
High Dose ◽  
Double Blind ◽  
Adequate Treatment ◽  
Baroreflex Failure

Afferent lesions of the arterial baroreflex occur in familial dysautonomia. This leads to excessive blood pressure variability with falls and frequent surges that damage the organs. These hypertensive surges are the result of excess peripheral catecholamine release and have no adequate treatment. Carbidopa is a selective DOPA-decarboxylase inhibitor that suppresses catecholamines production outside the brain. To learn whether carbidopa can inhibit catecholamine-induced hypertensive surges in patients with severe afferent baroreflex failure, we conducted a double-blind randomized crossover trial in which patients with familial dysautonomia received high dose carbidopa (600 mg/day), low-dose carbidopa (300 mg/day), or matching placebo in 3 4-week treatment periods. Among the 22 patients enrolled (13 females/8 males), the median age was 26 (range, 12–59 years). At enrollment, patients had hypertensive peaks to 164/116 (range, 144/92 to 213/150 mm Hg). Twenty-four hour urinary norepinephrine excretion, a marker of peripheral catecholamine release, was significantly suppressed on both high dose and low dose carbidopa, compared with placebo ( P =0.0075). The 2 co-primary end points of the trial were met. The SD of systolic BP variability was reduced at both carbidopa doses (low dose: 17±4; high dose: 18±5 mm Hg) compared with placebo (23±7 mm Hg; P =0.0013), and there was a significant reduction in the systolic BP peaks on active treatment ( P =0.0015). High- and low-dose carbidopa were similarly effective and well tolerated. This study provides class Ib evidence that carbidopa can reduce blood pressure variability in patients with congenital afferent baroreflex failure. Similar beneficial effects are observed in patients with acquired baroreflex lesions.

scholarly journals Conception Rate and Reproductive Hormone Secretion in Holstein Cows Immunized against Inhibin and Subjected to the Ovsynch Protocol

Animals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 313 ◽  
Author(s):  
Rihong Guo ◽  
Fang Chen ◽  
Cheng Mei ◽  
Zicun Dai ◽  
Leyan Yan ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Reproductive Performance ◽  
Luteal Phase ◽  
Low Dose ◽  
Follicle Stimulating Hormone ◽  
Hormone Secretion ◽  
Plasma Concentrations ◽  
High Dose ◽  
Reproductive Hormone ◽  
Conception Rates

This study was conducted to investigate the feasibility of improving fertility in dairy cows via immunization against inhibin. Thirty-two cows were divided into Control (n = 11), Low-dose (n = 10) and High-dose (n = 11) groups. The High-dose and Low-dose cows were treated with 1 and 0.5 mg of the inhibin immunogen, respectively. All the cows were subjected to the Ovsynch protocol from the day of antigen administration and were artificially inseminated. Blood samples were serially collected over a 24-day period from the start of the Ovsynch protocol to 14 days after insemination. The results showed that immunization against inhibin dose-dependently increased the plasma concentrations of follicle-stimulating hormone (FSH), estradiol (E2), and activin A, but decreased progesterone (P4) concentrations in the luteal phase. Immunization also increased the plasma interferon (IFN)-τ concentrations in pregnant cows on day 14 after initial insemination. The conception rates in High-dose (45.5%) and Low-dose (40%) cows marginally increased compared to that in Control cows (27.3%), but the increases were not significant (p > 0.05). In conclusion, a single immunization against inhibin has the potential to improve conception rates, despite impaired luteal development. To further improve the reproductive performance of dairy cows, additional luteal-stimulating treatments are suggested in combination with immunization against inhibin and Ovsynch techniques.

Effects of acetylsalicylic acid on pulmonary vascular tone and membrane permeability in blood-perfused dog lung

1993 ◽  
Vol 75 (6) ◽  
pp. 2561-2569 ◽  
Author(s):  
K. Kambara ◽  
M. Arakawa ◽  
T. Segawa ◽  
F. Ando ◽  
M. Ohno ◽  
...  
Keyword(s):  
Acetylsalicylic Acid ◽  
Extravascular Lung Water ◽  
Vascular Tone ◽  
Low Dose ◽  
Pressor Response ◽  
Plasma Concentrations ◽  
High Dose ◽  
Constant Flow ◽  
Lung Water ◽  
Pulmonary Vasoconstriction

We studied the effects of acetylsalicylic acid (ASA) on pressor response, microvascular filtration coefficient (Kf), extravascular lung water, and plasma concentrations of cyclooxygenase- and 5-lipoxygenase-derived products in 21 blood-perfused dog lungs with constant flow. The lungs were perfused for 1 h with an intrapulmonary injection of saline as vehicle (n = 5), a low dose of ASA [136 +/- 25 (SD) micrograms/ml perfusate; n = 5], a high dose of ASA (1,006 +/- 278 micrograms/ml perfusate; n = 6), or alloxan (1,000 mg; n = 5). Alloxan significantly increased Kf and extravascular lung water, whereas neither the low nor high dose of ASA increased Kf or extravascular lung water. The ASA-induced increase in vascular resistance did not correlate with the extent of the decrease in perfusate 6-keto-prostaglandin F1 alpha or the ratio of perfusate 6-ketoprostaglandin F1 alpha to thromboxane B2. Moreover, ASA did not enhance the generation of perfusate leukotrienes B4, D4, or E4. We conclude that pulmonary microvascular permeability is unaltered by ASA and that neither the decrease in plasma prostacyclin nor the increase in plasma sulfidopeptide leukotrienes may account for ASA-induced pulmonary vasoconstriction.

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