Ignite Creation Date:
2024-10-26 @ 3:35 PM
Last Modification Date:
2024-10-26 @ 3:35 PM
Study NCT ID:
NCT06505772
Status:
COMPLETED
Last Update Posted:
None
First Post:
2024-07-11
Brief Title:
Dexmedetomidine Improved Oxygenation and Reduced Shunt in One-Lung Ventilation at High-Risk Pediatric Thoracic Surgery
Sponsor:
None
Organization:
None
Study Overview
Official Title:
Dexmedetomidine Improves Oxygenation and Reduces Pulmonary Shunt in High-Risk Pediatric Patients Undergoing One-Lung Ventilation for Thoracic Surgery A Double-Blind Randomized Controlled Trial at Damascus University Childrens Hospital
Status:
COMPLETED
Status Verified Date:
2024-07
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
No
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
Children with high anesthetic risk who underwent Thoracic surgery with OLV one lung ventilation technique during general anesthesia were divided into two groups
The first is an intravenous injection of dexmedetomidine at a rate of 04 microgramskghour as a continuous intravenous infusion The second group the placebo group injected the second with a normal saline solution an infusion that will pass through the vein using blinded unmarked syringes
Three arterial blood gas ABG samples were taken during surgery at designated times Circulatory PaO2 values were recorded and the QsQt shunt value was calculated
The first is an intravenous injection of dexmedetomidine at a rate of 04 microgramskghour as a continuous intravenous infusion The second group the placebo group injected the second with a normal saline solution an infusion that will pass through the vein using blinded unmarked syringes
Three arterial blood gas ABG samples were taken during surgery at designated times Circulatory PaO2 values were recorded and the QsQt shunt value was calculated
Detailed Description:
Pediatric specific anatomy and physiology includes small ventricles with low systolic mass and poor ventricular compliance With decreased peripheral vascular resistance SVR The parasympathetic nervous system is dominant This explains why HR is delayed compared to changes in MAP and mean blood pressure is less affected and slower to respond As each terminal bronchiole opens into a single alveolus and initially forms clusters of clusters rather than fully developed alveolar clusters these clusters continue to grow until six to eight years of age to resemble adults The diaphragm is more horizontal which reduces its mechanical advantage Ventilation depends mainly on the diaphragm and the rate of its movements breathing movements Higher compliance of the thoracic wall is also seen with increased respiratory work
Decreased functional residual capacity FRC increases pulmonary shunting and leads to atelectasis One-lung ventilation OLV during general anesthesia can improve the surgical field of view which is often used in thoracic surgery However OLV can lead to a mismatch in the ventilationperfusion ratio VQ leading to increased shunt and pulmonary shunt fraction QsQt within the lungs and the occurrence of hypoxia The ratio between the rate of flow of unoxygenated blood from the pulmonary arteries to the pulmonary veins through the shunt Qs and the total rate of blood flow through the lungs Qt ie the ratio between the unoxygenated blood and the total blood is known as the pulmonary shunt fraction QsQt The FEV1FVC ratio represents the proportion of the total vital capacity that can be exhaled in the first second of forced expiration whereas FEV1 indicates Force Expiratory Volume in 1 second and FVC indicates Forced Vital Capacity
Hypoventilation-induced vasoconstriction HPV is the bodys primary compensatory mechanism against pulmonary constriction which is to divert pulmonary perfusion blood from the nonventilated area to the ventilated area thereby reducing pulmonary constriction and improving blood hypoxia HPV is affected by various factors including changes in pulmonary pressure alkalosis vasodilators and inhaled anesthetic gases which have the greatest effect The study was designed as a two-group controlled clinical trial using propofol which is known to have no effect on HPV
Dexmedetomidine is widely used as an anesthetic adjuvant It is a highly selective alpha2 adrenergic receptor agonist that directly stimulates peripheral alpha2 receptors to induce vasoconstriction and increase blood pressure as well as act on central alpha2 receptors to suppress sympathetic excitation which can dilate blood vessels and lower blood pressure Alpha adrenal blockade eliminates pulmonary arrhythmias that responded to non-adrenal but not hypoxia Due to the complex effects of dexmedetomidine on blood circulation it is difficult to predict its effects on intrapulmonary shunt and hypoventilation-induced vasoconstriction in patients during one-lung ventilation The hypothesis of our study predicted that dexmedetomidine would improve oxygenation Partial Pressure of Arterial Oxygen PaO2 and reduce pulmonary shunting during OLV in children
Decreased functional residual capacity FRC increases pulmonary shunting and leads to atelectasis One-lung ventilation OLV during general anesthesia can improve the surgical field of view which is often used in thoracic surgery However OLV can lead to a mismatch in the ventilationperfusion ratio VQ leading to increased shunt and pulmonary shunt fraction QsQt within the lungs and the occurrence of hypoxia The ratio between the rate of flow of unoxygenated blood from the pulmonary arteries to the pulmonary veins through the shunt Qs and the total rate of blood flow through the lungs Qt ie the ratio between the unoxygenated blood and the total blood is known as the pulmonary shunt fraction QsQt The FEV1FVC ratio represents the proportion of the total vital capacity that can be exhaled in the first second of forced expiration whereas FEV1 indicates Force Expiratory Volume in 1 second and FVC indicates Forced Vital Capacity
Hypoventilation-induced vasoconstriction HPV is the bodys primary compensatory mechanism against pulmonary constriction which is to divert pulmonary perfusion blood from the nonventilated area to the ventilated area thereby reducing pulmonary constriction and improving blood hypoxia HPV is affected by various factors including changes in pulmonary pressure alkalosis vasodilators and inhaled anesthetic gases which have the greatest effect The study was designed as a two-group controlled clinical trial using propofol which is known to have no effect on HPV
Dexmedetomidine is widely used as an anesthetic adjuvant It is a highly selective alpha2 adrenergic receptor agonist that directly stimulates peripheral alpha2 receptors to induce vasoconstriction and increase blood pressure as well as act on central alpha2 receptors to suppress sympathetic excitation which can dilate blood vessels and lower blood pressure Alpha adrenal blockade eliminates pulmonary arrhythmias that responded to non-adrenal but not hypoxia Due to the complex effects of dexmedetomidine on blood circulation it is difficult to predict its effects on intrapulmonary shunt and hypoventilation-induced vasoconstriction in patients during one-lung ventilation The hypothesis of our study predicted that dexmedetomidine would improve oxygenation Partial Pressure of Arterial Oxygen PaO2 and reduce pulmonary shunting during OLV in children
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None