Increases in Cardiac Output Can Reverse Flow Deficits from Vasospasm Independent of Blood Pressure: A Study Using Xenon Computed Tomographic Measurement of Cerebral Blood Flow

Neurosurgery ◽  
2003 ◽  
Vol 53 (5) ◽  
pp. 1044-1052 ◽  
Author(s):  
Dong H. Kim ◽  
Mathew Joseph ◽  
Saleem Ziadi ◽  
Joseph Nates ◽  
Mark Dannenbaum ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Cerebral Blood Flow ◽  
Subarachnoid Hemorrhage ◽  
Central Venous Pressure ◽  
Reverse Flow ◽  
Venous Pressure ◽  
Human Study ◽  
Central Venous ◽  
Computed Tomographic

Abstract INTRODUCTION Vasospasm after subarachnoid hemorrhage remains a management challenge. The accepted treatment involves hypertensive, hypervolemic, hemodilution therapy. However, there is variation in the application of this treatment. Most authors increase mean arterial pressure (MAP), which can be associated with significant morbidity. Others increase cardiac output (CO). In this study, we examined the relationship between volume status, CO, and MAP and cerebral blood flow (CBF) in the setting of vasospasm. METHODS A xenon blood flow tomography-based system was used to quantitate CBF. Sixteen patients with vasospasm after subarachnoid hemorrhage were treated with hypervolemia, phenylephrine to increase MAP, or dobutamine to increase CO. Direct CBF measurements were obtained before and after treatment. A strength of this study is that only one variable (central venous pressure, MAP, or CO) was manipulated in each patient, and the effect of this change was measured immediately. RESULTS With phenylephrine, mean MAP increased from 102.4 to 132.1 mm Hg. In regions of diminished CBF due to vasospasm, mean CBF increased from 19.2 to 33.7 ml/100 g/min. Similarly, dobutamine increased the cardiac index from a mean of 4.1 to 6.0 L/min/m2 and slightly decreased MAP. CBF increased from a mean of 24.8 to 35.4 ml/100 g/min. Both were statistically significant changes. With hypervolemia, the average central venous pressure increased from a mean of 5.4 to 7.3 cm H2O; no changes in mean CBF were noted. CONCLUSION This article reports the first human study that shows with direct measurements the independent influence of CO in the setting of vasospasm. Increases in CO without changes in MAP can elevate CBF. This finding has immediate clinical application because CO manipulation is much safer than increasing MAP. Because both interventions were equally efficacious, our protocol has been changed to augment CO as a first measure. Induced hypertension is reserved for patients in whom this initial treatment fails.

Cardiovascular actions of histamine and potassium

1959 ◽  
Vol 197 (5) ◽  
pp. 1005-1007 ◽  
Author(s):  
Calvin Hanna ◽  
Patricia B. McHugo ◽  
William H. MacMillan
Keyword(s):  
Cardiac Output ◽  
Central Venous Pressure ◽  
Potassium Chloride ◽  
Venous Pressure ◽  
Plasma Potassium ◽  
Dilution Method ◽  
Cardiac Rate ◽  
Central Venous ◽  
Arterial Blood ◽  
Cardiovascular Actions

The cardiovascular actions of intravenous histamine, in doses from 2.5 to 20 µg/kg of the free base, were studied in the pentobarbitalized dog using the dye dilution method. With the small dose there was a consistent but small initial increase in cardiac output and with the larger doses there was a biphasic change in output. Cardiac rate, central venous pressure, central blood volume, hematocrit and the mean circulation time were essentially unchanged. Infusions of histamine and of potassium chloride at the rate of 1 µg and 1 mg/kg/min., respectively, moderately increased the cardiac output. Potassium chloride had no effect on the arterial blood pressure, cardiac rate and central venous pressure. Both the infusion of potassium chloride and injection of histamine produced a comparable elevation of the plasma potassium. It is possible that the actions of histamine to increase the plasma potassium contribute to the cardiovascular actions of this amine, especially on the cardiac output.

scholarly journals Effects of Different Doses of Magnesium Sulfate on Pneumoperitoneum-related Hemodynamic Changes in Patients Undergoing Gastrointestinal Laparoscopy: a randomized, double-blind, controlled trial

2019 ◽  
Author(s):  
Wei Tan ◽  
Dong-chen Qian ◽  
Meng-meng Zheng ◽  
Xuan Lu ◽  
Yuan Han ◽  
...  
Keyword(s):  
Cardiac Output ◽  
Mean Arterial Pressure ◽  
Arterial Pressure ◽  
Central Venous Pressure ◽  
Magnesium Sulfate ◽  
Systemic Vascular Resistance ◽  
Vascular Resistance ◽  
Venous Pressure ◽  
Control Group ◽  
Central Venous

Abstract Background: The infusion of magnesium sulfate is well known to reduce arterial pressure and attenuate hemodynamic response to pneumoperitoneum. This study aimed to investigate whether different doses of magnesium sulfate can effectively attenuate the pneumoperitoneum-related hemodynamic changes and the release of vasopressin in patients undergoing laparoscopic gastrointestinal surgery. Methods: Sixty-nine patients undergoing laparoscopic partial gastrectomy were randomized into three groups: group L received magnesium sulfate 30 mg/kg loading dose and 15 mg/kg/h continuous maintenance infusion for 1 h; group H received magnesium sulfate 50 mg/kg followed by 30 mg/kg/h for 1 h; and group S (control group) received same volume 0.9% saline infusion, immediately before the induction of pneumoperitoneum. Systemic vascular resistance (SVR), cardiac output (CO), mean arterial pressure (MAP), heart rate (HR), central venous pressure(CVP), serum vasopressin and magnesium concentrations were measured. The extubation time, visual analogue scale were also assessed. The primary outcome is the difference in SVR between different groups. The secondary outcome is the differences of other indicators between groups, such as CO, MAP, HR, CVP, vasopressin and postoperative pain score. Results: Pneumoperitoneum instantly resulted in a significant reduction of cardiac output and an increase in mean arterial pressure, systemic vascular resistance, central venous pressure and heart rate in the control group (P < 0.01). The mean arterial pressure (T2 – T4), systemic vascular resistance (T2 – T3), central venous pressure(T3-T5) and the level of serum vasopressin were significantly lower (P < 0.05) and the cardiac output (T2 – T3) was significantly higher (P < 0.05) in group H than those in the control group. The mean arterial pressure (T4), systemic vascular resistance (T2), and central venous pressure(T3-T4) were significantly lower in group H than those in group L (P < 0.05). Furthermore, the visual analog scales at 5 min and 20 min, the level of vasopressin, and the dose of remifentanil were significantly decreased in group H compared to the control group and group L (P < 0.01). Conclusion: Magnesium sulfate could safely and effectively attenuate the pneumoperitoneum-related hemodynamic instability during gastrointestinal laparoscopy and improve postoperative pain at serum magnesium concentrations above 2 mmol/L.

scholarly journals Effects of Different Doses of Magnesium Sulfate on Pneumoperitoneum-related Hemodynamic Changes in Patients Undergoing Gastrointestinal Laparoscopy

2019 ◽  
Author(s):  
Wei Tan ◽  
Dong-chen Qian ◽  
Meng-meng Zheng ◽  
Xuan Lu ◽  
Yuan Han ◽  
...  
Keyword(s):  
Cardiac Output ◽  
Mean Arterial Pressure ◽  
Arterial Pressure ◽  
Central Venous Pressure ◽  
Magnesium Sulfate ◽  
Systemic Vascular Resistance ◽  
Vascular Resistance ◽  
Venous Pressure ◽  
Control Group ◽  
Central Venous

Abstract Background: The infusion of magnesium sulfate is well known to reduce arterial pressure and attenuate hemodynamic response to pneumoperitoneum. This study aimed to investigate whether different doses of magnesium sulfate can effectively attenuate the pneumoperitoneum-related hemodynamic changes and the release of vasopressin in patients undergoing laparoscopic gastrointestinal surgery. Methods: Sixty-nine patients undergoing laparoscopic partial gastrectomy were randomized into three groups: group L received magnesium sulfate 30 mg/kg loading dose and 15 mg/kg/h continuous maintenance infusion for 1 h; group H received magnesium sulfate 50 mg/kg followed by 30 mg/kg/h for 1 h; and group S (control group) received same volume 0.9% saline infusion, immediately before the induction of pneumoperitoneum. Systemic vascular resistance (SVR), cardiac output (CO), mean arterial pressure (MAP), heart rate (HR), central venous pressure(CVP), serum vasopressin and magnesium concentrations were measured. The extubation time, visual analogue scale were also assessed. The primary outcome is the difference in SVR between different groups. The secondary outcome is the differences of other indicators between groups, such as CO, MAP, HR, CVP, vasopressin and postoperative pain score. Results: Pneumoperitoneum instantly resulted in a significant reduction of cardiac output and an increase in mean arterial pressure, systemic vascular resistance, central venous pressure and heart rate in the control group (P < 0.01). The mean arterial pressure (T2 – T4), systemic vascular resistance (T2 – T3), central venous pressure(T3-T5) and the level of serum vasopressin were significantly lower (P < 0.05) and the cardiac output (T2 – T3) was significantly higher (P < 0.05) in group H than those in the control group. The mean arterial pressure (T4), systemic vascular resistance (T2), and central venous pressure(T3-T4) were significantly lower in group H than those in group L (P < 0.05). Furthermore, the visual analog scales at 5 min and 20 min, the level of vasopressin, and the dose of remifentanil were significantly decreased in group H compared to the control group and group L (P < 0.01). Conclusion: Magnesium sulfate could safely and effectively attenuate the pneumoperitoneum-related hemodynamic instability during gastrointestinal laparoscopy and improve postoperative pain at serum magnesium concentrations above 2 mmol/L.

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