Vascular system INDEX

SVRI Systemic vascular resistance index VT Ventricular tachycardia... 

Administration by inhalation has been explored by Brilli [124], mentioned previously for his work with NONOates. Here he uses one of these same NONOates, DMAEP/NO (see Fig. 8.11), in aerosol form. When administered in an aerosolized state, DMAEP/NO again shows selective pulmonary vasodilation in a porcine model. This is achieved without affecting the systemic vascular resistance index (SVRI) or the cardiac index (Cl). Work from the same year by Adrie et al. [125] compared aerosolized DEA/NO with aerosolized SNP and inhaled NO, in sheep. As the NONOate has a short half-life (2.1 min), it was predicted that this would be a selective pulmonary vasodilator. However, compared with inhaled NO this was not observed, though SNP... 

Figure 3.3 Graph showing mean values for systolic blood pressure (SBP) and systemic vascular resistance index (SVRI) in young (n=20) and elderly (n=20) patients during induction of anaesthesia with isoflurane (1 MAC) in 100% oxygen. Data from McKinney MS, Fee JPH, Clarke RSJ. British Journal of Anaesthesia 1993 71 696-701.)...

A 36-year-old man with a pheochromocytoma underwent adrenalectomy. After induction of anesthesia he was given intravenous labetalol 30 mg, and after intubation his blood pressure rose from 147/85 to 247/ 150 mmHg, his systemic vascular resistance index rose from 1958 to 3458 dyn sec m cm, and his cardiac index fell to 3.6 1 min m. During tumor resection, he was given sodium nitroprusside to reduce his blood pressure. After tumor resection, his blood pressure fell to 77/52 mmHg and his systemic vascular resistance index to 1635 dyn sec m cm. His blood pressure was effectively controlled with dobutamine. 

On the premise that phosphodiesterase inhibitors also inhibit the production of cytokines, milrinone has been used in the treatment of nine patients with the systemic inflammatory response sjmdrome and compared with seven patients with congestive heart failure (4). In both groups mikinone significantly altered cardiac index, pulmonary capillary wedge pressure, and left ventricular stroke work index. In the patients with cardiac failure it also reduced systemic vascular resistance index, and the dose of adrenaline had to be increased substantially during milrinone infusion to counteract vasodilatation. 

Mice were inoculated Lv. with a single injection of the pyran sample, 25 mg/kg and at intervals thereafter were injected i.v. with Cl 1/1431 Pelikan carbon. The method used was that of Biozzi et al. (1953), wherein colloidal carbon was injected in the tail vein at a dose of 160 mg/kg and serial samples taken for optical density readings. The phagocytic index, K, of the carbon in the vascular system was calculated as previously described (Regelson and Munson, 1970 Regelson et al, 1970 Munson et al, 1970). 

In a prospective study in 32 elderly patients, ASA grades 1-3, who received spinal anesthesia with bupivacaine 10-17.5 mg, baseline blood pressure variabDity and near-infrared spectroscopy reduction predicted hypotension with high sensitivity (0.73 and 0.90 respectively) and specificity (0.78 and 0.64, respectively) [32. However, heart rate, systemic vascular resistance index, baroreceptor sensitivity, and heart rate variability were of limited predictive value. 

It has been shown that CGRP is released into the circulation during the development of human sepsis and septic shock (A8). Plasma CGRP levels correlated with the APACHE II score as well as with cardiac index and systemic vascular re-sistence index. There is also a relationship between the initial plasma CGRP levels and the severity of the disease at the time of admission to the ICU. Plasma CGRP levels are related to the hemodynamic changes seen early in septic shock. 

Dofetilide does not significantly alter the mean arterial blood pressure, cardiac output, cardiac index, stroke volume index, or systemic vascular resistance. There is a slight increase in the delta pressure/delta time (dP/dt) of ventricular myocytes. 

Carvedilol significantly reduces systemic blood pressure, pulmonary artery pressure, right atrial pressure, systemic vascular resistance, and heart rate, while stroke volume index is increased. 

Serotonin (5-hydroxytryptamine, 5-HT) is synthesised in enterochromaffin cells, largely in the gut, and also extensively taken up into blood platelets from which it is released to have vascular effects. It has complex effects on the cardiovascular system, varying with the vascular bed and its physiological state it generally constricts arterioles and veins and induces blood platelet aggregation it stimulates intestinal and bronchial smooth muscle. Carcinoid tumours secrete serotonin and symptoms may be benefited by serotonin antagonists, e.g. cyproheptadine, methysergide and sometimes by octreotide (see Index). It is a neurotransmitter in the brain. 

In a comprehensive comparison of the pharmacokinetics and pharmacodynamics of dextran and etherified starch (8), the effects of etherified starch on the cardiovascnlar system have been delineated. The mean arterial pressnre, central venous pressure, wedge pressure, cardiac index, left ventricular stroke work index, and stroke output aU rise, whereas the pulmonary vascular resistance falls. Oxygen availability to the tissues is improved. The effects of etherified starch on blood viscosity and erythrocjde aggregation, in particular, are more pronounced than with dextran. 

Price ML, Millar B, Grounds M, Cashman J. Changes in cardiac index and estimated systemic vascular resistance during induction of anaesthesia with thiopentone, metho-hexitone, propofol and etomidate. Br J Anaesth 1992 69(2) 172-6. 

Labetalol is generally used effectively as an antihypertensive drug without reports of high vascular resistance, even in patients with pheochromocytoma. However, a case of pheochromocytoma with increased systemic vascular resistance and reduced cardiac index has been described (4). 

A 42-year-old woman suffered an acute anterior myocardial infarction, initially associated with pulmonary edema. After hemodjmamic stabilization she was given lisinopril 10 mg oraUy. Two hours later she developed circulatory failure in conjunction with acute renal insufficiency. Right heart catheterization showed markedly reduced systemic vascular resistance but a normal cardiac index. After the usual causes of cardiogenic shock had been ruled out, repeated fluid challenges and intravenous noradrenaline failed to improve her hemodynamic status. She was therefore given angiotensin II intravenously (5-7.5 pg/minute), which immediately and markedly raised the systematic vascular... 

A 16-year-old boy who took long-term verapamil after a Mustard operation for transposition of the great arteries developed severe congestive heart failure, which did not respond to diuretics. Systemic vascular resistance was increased by 75% and pulmonary vascular resistance by 150% the cardiac index was reduced from 3.0 to 1.8 1/minute/m. Ejection fraction and atrial pressure were unchanged and neurohormonal causes were excluded. The heart failure resolved after withdrawal of verapamil. 

In ponies, desflurane (MAC) caused a decrease in arterial blood pressure and systemic vascular resistance while heart rate and cardiac index were not changed significantly (Clarke et al 1996). Increasing the concentration of desflurane to 1.3 times MAC resulted in further depression of the arterial blood pressure and a significant decrease in the cardiac index, attributed to the onset of cardiac depression at higher concentrations (Clarke et al 1996). Desflurane also results in respiratory depression there is a significant increase in PaC02 at MAC (Clarke et al 1996). In other species, the cardiopulmonary effects of desflurane are considered to be approximately equal to those of isoflurane, but a direct comparison of desflurane and other inhalation anesthetics has not yet been carried out in the horse. 

Fig. 11. The hemodynamic response to exercise is influenced by the p2-Ilel64 polymorphism in patients with heart failure. Exercise-induced changes were significantly lower in patients with Ilel64 for 02, stroke volume (SV), cardiac index (Cl), and systemic vascular resistance (SVR). All changes represent increases by the indicated percentage, except for SVR, which was a decrease. HR, heart rate. / < 0.05 vs Thrl64. V02 is maximal oxygen consumption. (Reprinted with permission from ref. 34.)...

DITPA treatment improved left ventricular performance in rat and rabbit post-M I models of heart failure. In a double-blind, placebo controlled, pilot phase II clinical study in 19 patients with NYHA class II or III CHF in 2003, DITPA demonstrated a significant increase in cardiac index, as well as improvements in diastolic function, systemic vascular resistance, and cholesterol and triglyceride levels. In this study, DITPA was well tolerated, with no significant increase in heart rate or significant adverse events. Subsequently, a larger trial was initiated which, however, was discontinued in October 2006, based on a business decision by Titan. 

---