Effects of Crystalloid Preloading (20 ml/kg) on Hemodynamics in Relation to Postural Changes in Patients Undergoing Neurosurgical Procedures in Sitting Position

Abstract

Background:Hemodynamic disturbances are common during positioning the patients from supine to sitting for neurosurgical procedures. The reported incidence of hypotension varies from 5% to 32%. The aim of the study was to study the effect of crystalloid preloading on hemodynamic parameters during positioning the patient from supine to sitting position.Materials and Methods:In this prospective observational trial, 20 patients were enrolled. Two patients had a patent foramen ovale on transesophageal echocardiography and were excluded from the study. All the patients received 20 ml/kg of crystalloid (Ringer's lactate) before initiation of positioning. Physiological hemodynamic parameters such as heart rate, mean arterial pressure, central venous pressure, cardiac output (CO), stroke volume variation (SVV), cardiac index (CI), stroke volume (SV), and maximum and minimum inferior vena caval diameter (IVCD) were recorded after induction, during positioning at 30°, 60° inclination of the operating table and after the final sitting position.Results:Hemodynamic parameters were well maintained during positioning of the patients from supine to sitting position. Crystalloid preloading prevented the hypotension during positioning. There were no significant changes in hemodynamic parameters such as CO, SVR, SVV, CI, and SV. We did not find any correlation with changes in IVCD with changes in CO.Conclusion:A volume of 20 ml/kg of crystalloid preloading before positioning the patient from supine to sitting position maintains the hemodynamic stability and avoids the vasopressor requirement.

Effect of Preanesthetic Fluid Loading on Postinduction Hypotension and Advanced Cardiac Parameters in Patients with Chronic Compressive Cervical Myelopathy: A Randomized Controlled Trial

“… 22 In an observational study involving 20 patients, preloading with 20 mL/kg Ringer's lactate before positioning from supine to sitting prevented the occurrence of hypotension without significant changes in CO, SVR, SVV, CI, and SV. 23 Though the decrease in MAP with prone positioning was more pronounced in patients without preloading in our study, this difference was not statistically significant. Similarly, there was no significant difference in cardiac indices between the groups with change to prone position.…”

Sitting Position in Neurosurgery

“…This maintained hemodynamic stability and avoided any vasopressor requirement. 29 Dohn and Gardner in 1956 devised a "G" suit that consisted of inflatable leggings and an abdominal binder, which, by constricting the lower part of the body, prevented pooling of blood and increased the venous return, and thus reduced hypotension in anesthetized patients in this position. 30 Meyer et al studied the use of antishock trousers (MAST suit) and PEEP 8 to 10 cm H 2 O in children undergoing neurosurgical procedures in the sitting position.…”