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A clinical study to evaluate the fluid response in patients undergoing neurosurgery.

Not yet recruiting
Conditions
Measurement and Monitoring,
Registration Number
CTRI/2023/08/056665
Lead Sponsor
AIIMS New delhi
Brief Summary

**Perioperative management**

·        Allpatients will receive standard intra-operative monitoring, includingheart rate (HR), peripheral oxygen saturation(SpO2), continuouselectrocardiography (ECG) and noninvasive blood pressure monitoring (NIBP).

·        After pre-oxygenation, general anaesthesia willbe   induced  with  propofol, fentanyl and rocuronium (0.8to 1 mg kg—1), and maintained with propofol (100 - 150 mcg kg—1min—1) or sevoflurane (1to 2%) along with fentanyl (1 to 2 mcg kg—1hr—1).

·        Anestheticadministration was targeted to maintain a bispectral index (BIS) of 40 to 60throughout the surgical procedure.[22](file:///C:/Users/Sr%20Lounge-1/Downloads/3.%20complete%20PROTOCOL%20-%20TVC.docx#_bookmark21)

·        Allpatients will receive Sodium chloride(0.9%) solution at 4 ml/kg/hour as a maintenancefluid infusion during surgery and will be ventilated at baseline involume-control mode with the following settings: VT of 6 ml/ kgPBW and positive end-expiratory pressure set 5 cmH2O toachieve and maintain a peripheral oxygen saturation of 96% and an end-tidalcarbon dioxide (EtCo2) concentration between 30 and 35 mmHg.

·        The PBW(kg) will be calculated as follows: X 0.91[height (cm) - 152.4]; (X 50 for menand 45.5 for women).

·        Afterinduction of general anesthesia, invasive blood pressure monitoring will beobtained by inserting a 20-G cannula into the radial artery.  A square-wave test will be used in allpatients to exclude under or overdamping of the pressure signal.[23](file:///C:/Users/Sr%20Lounge-1/Downloads/3.%20complete%20PROTOCOL%20-%20TVC.docx#_bookmark22)

 **Hemodynamic monitoring**

Radial artery catheter will be connected to the FlowTracsystem (version 4.0; EdwardsLifesciences, Irvine, CA, USA). We will continuously monitor stroke volume(SV), stroke volume index (SVI), cardiac output (CO), cardiac index (CI) andSVV through FlowTrac /EV1000 system. 43,44 PPV will be continuouslyrecorded on a Nihon -Kohden monitoring system (Nihon Kohden Corporation,Japan).

**Study protocol**

Measurements will be started during aperiod of hemodynamic stability (definedas changes in mean arterialpressure less than 10% over 5 min[7,26](file:///C:/Users/Sr%20Lounge-1/Downloads/3.%20complete%20PROTOCOL%20-%20TVC.docx#_bookmark10)) after positioning the patient in lateral. All readings will betaken before the skin incision.

The study protocol will start with recording an initial set of measurements (Baseline).  TVC will be applied by increasing the TV up to 8 ml/ kg PBW and PPV and SVVchanges were recorded(∆ PPV and ∆ SVV, respectively, calculated as percentage of variationsbetween the values of PPV and SVV recorded at bassline -1 and 1 min after the VTincrease).

Following this, the TV will be reduced back to 6 ml/ kg PBW andafter 1 min, a set of measurements will be recorded (Baseline 2) and the fluidchallenge (FC) of 250 ml of sodium chloride ( 0.9%) solution will be infusedover 10 min and SV,SVI will be noted. Onlythe haemodynamic data, obtained from the first fluid challenge administered toeach enrolled patient will be used for the analysis. Positive end-expiratorypressure will be kept constant during the study period. For the safety of the patient, the interruption of the protocolwill be at discretion of the attending anesthetist.

 **Samplesize calculation**

·        The sample size of the study was calculated by means of thecomparison of the areas under the ROC curves test (AUC). For this purpose, we predicted an AUC of at least   0.75,which is the threshold for considering a diagnostic test as accurate,[29](file:///C:/Users/Sr%20Lounge-1/Downloads/3.%20complete%20PROTOCOL%20-%20TVC.docx#_bookmark12) and comparedit with the null hypothesis (AUC 0.50; no discriminatingpower). Accordingly, a sample size of 38 patients was calculated (type I error of 5% and type II error of 20%).With the expectation of a 10% dropout rate, 42 patients will be enrolled in thestudy.

**Statistical analysis**

A receiver operating characteristic (ROC) curve approachwill be used to evaluate the reliability of TVC test in predicting fluid responsiveness. ROC curves willbe constructed for PPV and SVV valuesbefore fluid challenge administration; for the percentage changein PPV and SVV between 6-and 8-ml/ kgPBW ventilation after 1min of TVC application.

A patient will beconsidered fluid responsive if the SVI increased at least 10% after fluidchallenge administration.[7,8](file:///C:/Users/Sr%20Lounge-1/Downloads/3.%20complete%20PROTOCOL%20-%20TVC.docx#_bookmark10) Cut-off values will be chosen with the highestYouden index and, finally, statistically significant ROC curves (*P* < 0.05) were compared using the DeLong test.[27](file:///C:/Users/Sr%20Lounge-1/Downloads/3.%20complete%20PROTOCOL%20-%20TVC.docx#_bookmark10)  Normaldistribution will be evaluated by means of the D’Agostino-Pearson test and,accordingly, data are expressed as median with interquartile [IQR] range ormean (SD).

Changesin continuous variables after TVC will be compared using a paired *t* test or Wilcoxon signed rank sum test,while an independent *t* test orMann–Whitney *U* test was used forsubgroup comparisons, as appropriate. For dichotomousor categorical variables, a Chi-square test for comparison of proportions willbe applied. Statistical analyses will be conducted using STATA and or Rsoftware.

Forall comparisons, we will consider significant *P* values less than 0.05.

Detailed Description

Not available

Recruitment & Eligibility

Status
Not Yet Recruiting
Sex
All
Target Recruitment
42
Inclusion Criteria

All elective neurosurgical patients (age >18 years, ASA I II) requiring lateral positioning will be considered eligible.

Exclusion Criteria
  • oAny recurrent cardiac arrhythmia; reduced ventricular systolic function.
  • left (ejection fraction <40%), oBMI more than 30 oIntra-operative use of vasopressors or inotropes before or during TVC oChronic lung disease oPre-operative use of beta blocking agents.

Study & Design

Study Type
Observational
Study Design
Not specified
Primary Outcome Measures
NameTimeMethod
To assess the reliability of changes in pulse pressure variation (PPV) and stroke volume variation (SVV) values induced by tidal volume challenge in predicting fluid responsiveness in patients undergoing neurosurgery in the lateral position under 6 ml/kg (PBW).Starting point - At the point when lateral postion of the patint is achieved with hemodynamic stability. | End Point - At the point when Hemodynamic parameters are noted after the fluid challenge.
Secondary Outcome Measures
NameTimeMethod
To assess the reliability of pulse pressure variation (PPV) and stroke volume variation (SVV) at 6 ml/kg and 8 ml/kg.Starting point - At the point when lateral postion of the patint is achieved with hemodynamic stability.

Trial Locations

Locations (1)

AIIMS, New Delhi

🇮🇳

South, DELHI, India

AIIMS, New Delhi
🇮🇳South, DELHI, India
Dr Niraj Kumar
Principal investigator
9013770806
drnirajaiims@gmail.com

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