can the change in size of large blood vessel in stomach during transiently increasing breath volume predict the response to fluid therapy in seriously ill patients on mechanical ventilator?
- Conditions
- Acute respiratory distress syndrome, (2) ICD-10 Condition: B972||Coronavirus as the cause of diseases classified elsewhere, (3) ICD-10 Condition: I959||Hypotension, unspecified, (4) ICD-10 Condition: R098||Other specified symptoms and signsinvolving the circulatory and respiratory systems, (5) ICD-10 Condition: J189||Pneumonia, unspecified organism, (6) ICD-10 Condition: J99||Respiratory disorders in diseasesclassified elsewhere,
- Registration Number
- CTRI/2021/09/036633
- Lead Sponsor
- Natesh Prabu R
- Brief Summary
Fluid administration is the first line of treatment in patients with acute circulatory failure. It is recommended to use dynamic indices to predict fluid responsiveness. The current SARS CoV2 pandemic has posted a real challenge with diverse presentation, with two lung phenotypes, (L-phenotype and H phenotypes) and most patients who required intensive care unit admission had ARDS.1 The circulatory failure in such patients is more complex due to varied prevalence of myocardial injury, distributive shock, cytokine storm and right ventricular dysfunction (proportion of ARDS patients). Recent surviving sepsis campaign suggested restricted fluid strategy in patients with ARDS due to SARS CoV2 and to use appropriate dynamic parameters to decide fluid therapy.2 Various dynamic indices which depend on cardiopulmonary interactions like stroke volume variation (SVV) and pulse pressure variation (PPV), aortic root velocity variation, inferior vena cave distensibility are superior to static indices and shown to accurately predict fluid responsiveness.3 Among all available parameters, the parameters derived using ultrasonography are less invasive, repeatable, easy to do and available at bedside. One such parameter is Inferior vena cava diameter variability (IVC-V), which is routinely measured in all patients with shock, during screening using echocardiography which is calculated as IVC distensibility index (IVC-DI) during controlled ventilation and has been shown to reliably predict fluid responsiveness in mechanically ventilated patients.4,5,6 The IVC-V depends on the variations in intrathoracic pressure, abdominal pressure, and compliance of the vessel. The major limitation for using IVC-DI is first, it is not tested in ARDS patients with low tidal ventilation (≤6mL/kg PBW) and poor lung compliance Crs is <30 mL/cmH2O. Most of the studies that tested IVC-DI used tidal volume > 8 mL/kg PBW and not in low tidal volume ventilation 6,7. When Vt less than 8 mL/kg is used, there may be smaller variations in intrathoracic pressure and in turn intrathrocic blood volume leading to smaller variations in IVC dimensions, thus leading to false negative results irrespective of the volume status.8 Second, it is not feasible to use IVC-DI in patients with prone ventilation. Both these limitations prevent the use of this test in the COVID pandemic where most of the patients are either ventilated with low tidal volume or in prone position or both.
To overcome the limitation of low TV, a newly developed test “tidal volume challenge,†which involves transiently increasing the TV from 6mL/kg PBW to 8mL/kg PBW for one minute has shown reliability in predicting fluid responsiveness using PPV9. Recent study showed improved reliability of IVC-DI after “tidal volume challenge†with moderate discrimination.10 So “tidal volume challengeâ€, is a potential alternative for using IVC-DI in patient with low tidal ventilation. But all patients were in supine position. IVC-DI cannot be used in prone position due to inaccessibility of echocardiography window in prone position. An alternative approach to IVC, through the liver, i.e. lateral view or transhepatic view is a potential option for patients in prone position. Few previous studies have shown the feasibility of using this approach and its ability to predict FR.11,12 Also, previous studies have shown moderate correlation of IVC diameter and good agreement in IVC variability between both views in critically ill patients.13,14,15 Also, studies have shown that it is easy to get good view of IVC through lateral approach than subcostal approach15. This opens an opportunity to use the IVC-DI through lateral approach in prone ventilation. Thus, using the lateral approach combining with tidal volume challenge it is possible to use IVC-DI in patients with low tidal volume ventilation and in prone position. This is easy, repeatable, and feasible in all prone ventilated patients and we hope it would add value to the tests of fluid responsiveness in prone ventilation and it will be of immense help during this CVOID pandemic.
So, we would like to determine the reliability of IVC-DI at low Vt and whether the “tidal volume challenge†can improve the reliability of IVC-DI in predicting fluid responsiveness in patients receiving low Vt ventilation.
**Methodology**
All patients enrolled will be screened for fulfillment of inclusion criteria. Acute circulatory failure will be defined as presence of any of the following. (1) systolic blood pressure < 90 mmHg (or a decrease > 40 mmHg in previously hypertensive patients), (2) requirement of vasopressors or inotropes to maintain mean arterial pressure >65mmHg (3) urine output < 0.5 mL/kg/hour for at least 2 h, (4) tachycardia or (5) presence of skin mottling or increased capillary refill time or cold peripheries or elevated serum lactates (along with any other signs). All patients enrolled who have an arterial catheter the arterial pressure transducers will be attached to the patient’s upper arm at the level of the cardiac cavities. ETCO2 module will be connected to the monitor. This study will not be performed more than once in a same patient on same day. Not more than two observations per patient will be taken. Demographic data of patients including age, sex, height, weight, predicted body weight (PBW), APACHE II on admission, primary diagnosis, and reason for ICU admission of patients will be recorded. Indication for low tidal volume ventilation will be recorded. Dose of vasopressors used if any, will be recorded. The vasoactive medications would be kept constant during the study period. The Positive end expiratory pressure (PEEP) will be kept constant during the study period. Various Respiratory and hemodynamic parameters will be recorded at various intervals as per study design below. ICU and hospital outcome of the patient will be recorded. Echocardiography will be done during PLRT, VTI will be measured in apical 5 chamber view, 3 readings of VTI will be averaged during end expiration. The VTI measurement during PLR will be done by same operator and the hand position and probe position, doppler angle will be kept constant during the PLRT.
**Study Design**
The baseline data will be collected as elaborated above from eligible patients. Arterial lactate and mixed central venous oxygen saturation values (ScVO2) if available will be recorded. All patients will be monitored for 15 minutes at 6 ml/kg PBW for any variability in vital parameters. The following set of hemodynamic variables, i.e., heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), cardiac output (CO- VTI), PPV, perfusion index and respiratory variables i.e., plateau pressure (Pplat) and static compliance of the respiratory system (calculated using the formula Vt/ Pplat-PEEP) will be recorded. This set of readings will be recorded at baseline and repeated at various intervals (refer to flowchart). The “tidal volume challenge†will be performed and after one minute a set of readings will be recorded. The tidal volume will be decreased back to 6 ml/kg IBW. After one minute a set of readings will be recorded. These reading will be timed when the patient is scheduled for prone ventilation by treating team. IVC maximum and minimum diameters will be measured using ultrasound machine (SonoSite, USA) With phased array probe (frequency 1-5MHz). The IVC will be examined subcostal view in longitudinal section. Similarly, the IVC maximum and minimum will be measured via lateral approach at anterior mid axillary line. Its maximum and minimum diameter will be measured in M-mode coupled to two-dimensional mode, just upstream of the origin of the suprahepatic vein on expiration. Measurements will be considered only when the M-mode tracing is exactly perpendicular to the IVC (Fig 1). The IVC distensibility index (IVC-DI) will be calculated using the following formulae.
1. maximum diameter – minimum diameter /minimum diameter of IVC × 100
2. maximum diameter – minimum diameter /mean diameter of IVC × 100
The echocardiography readings will be measured using ultrasound machine (SonoSite, USA) With phased array probe (frequency 1-5MHz). (Fig 1). The VTI will be measured before, during and after Passive leg raise test. Patients will be classified as fluid responders and non-responders based on PLRT responsiveness. All measurement will be done by intensivists trained in echocardiography.
Once after prone positioning, the “tidal volume challenge†and IVC-DI \_lateral will be performed. Set of readings will be recorded. (Refer flow chart).
The ratio of the heart rate and respiratory rate (HR/RR) and difference between Pplat and PEEP will be calculated for each interval. Patients will be divided into two groups Responders and Non-Responders based on increase in VTI/Cardiac index >15% after PLRT. At least 10% of readings will be measured by another investigator to see for inter rater variability. Before starting the study five to six successive reading of IVC distensibility will be done by same operator to look for least significant change.
No therapeutic intervention will be carried out and no fluid bolus will be given.
Flowchart
Baseline record readings 1 (at 6 ml/kg PBW)
Baseline IVC-DI- semi recumbent
↓
Increase tidal volume from 6mL/kg PBW to 8mL/kg PBW (Tidal volume challenge)
After 1 min, record readings
↓
Decrease tidal volume back to 6ml/kg PBW
After 1 min, record readings,baseline 2
↓
Baseline IVC-DI\_lateral- semi recumbent, baseline 3
↓
Tidal volume challenge
↓
baseline 4
Prone position – wait for 10-15 mins
↓
Record readings (baseline-5)
↓
Tidal volume challenge (PPV, IVC-DI\_lateral) ↓
Decrease tidal volume back to 6ml/kg PBW
Record readings, baseline 6 (PPV, IVC-DI\_lateral)
**Reference:**
1. Gattinoni L, Chiumello D, Caironi P, et al. COVID-19 pneumonia: different respiratory treatments for different phenotypes? Intensive Care Med 2020; 46: 1099–1102.
2. Alhazzani W, Møller MH, Arabi YM, et al. Surviving Sepsis Campaign: guidelines on the management of critically ill adults with Coronavirus Disease 2019 (COVID-19). Springer Berlin Heidelberg, 2020. Epub ahead of print 2020. DOI: 10.1007/s00134-020-06022-5.
3. Michard F, Teboul JL. Using heart-lung interactions to assess fluid responsiveness during mechanical ventilation. Crit Care 2000; 4: 282–9.
4. Barbier C, Loubières Y, Schmit C, et al. Respiratory changes in inferior vena cava diameter are helpful in predicting fluid responsiveness in ventilated septic patients. Intensive Care Med 2004; 30: 1740–1746.
5. Feissel M, Michard F, Faller JP, et al. The respiratory variation in inferior vena cava diameter as a guide to fluid therapy. Intensive Care Med 2004; 30: 1834–1837.
6. Zhang Z, Xu X, Ye S, et al. Ultrasonographic measurement of the respiratory variation in the inferior vena cava diameter is predictive of fluid responsiveness in critically ill patients: Systematic review and meta-analysis. Ultrasound in Medicine and Biology 2014; 40: 845–853.
7. Vignon P, Repessé X, Bégot E, et al. Comparison of echocardiographic indices used to predict fluid responsiveness in ventilated patients. 1–46.
8. Via G, Tavazzi G, Price S. Ten situations where inferior vena cava ultrasound may fail to accurately predict fluid responsiveness : a physiologically based point of view. Intensive Care Med 2016; 42: 1164–1167.
9. Myatra SN, Prabu NR, Divatia JV, et al. The Changes in Pulse Pressure Variation or Stroke Volume Variation After a “Tidal Volume Challenge†Reliably Predict Fluid Responsiveness During Low Tidal Volume Ventilation\*. Crit Care Med 2017; 45: 415–421.
10. Taccheri T, Gavelli F, Teboul JL, et al. Do changes in pulse pressure variation and inferior vena cava distensibility during passive leg raising and tidal volume challenge detect preload responsiveness in case of low tidal volume ventilation ? Crit Care 2021; 1–12.
11. Finnerty NM, Panchal AR, Boulger C, et al. Inferior vena cava measurement with ultrasound: What is the best view and best mode? Western Journal of Emergency Medicine 2017; 18: 496–501.
12. Hensley J, Wang H. Assessment of Volume Status During Prone Spine Surgery via a Novel Point-of-care Ultrasound Technique. Cureus; 11. Epub ahead of print 6 May 2019. DOI: 10.7759/cureus.4601.
13. Garijo JM, Wijeysundera DN, Munro JC, et al. Correlation Between Transhepatic and Subcostal Inferior Vena Cava Views to Assess Inferior Vena Cava Variation: A Pilot Study. J Cardiothorac Vasc Anesth 2017; 31: 973–979.
14. Kulkarni AP, Janarthanan S, Harish MM, et al. Agreement between inferior vena cava diameter measurements by subxiphoid versus transhepatic views. Indian J Crit Care Med 2015; 19: 719–722.
15. Zhang Q, Liu D, Wang X, et al. Inferior vena cava diameter and variability on longitudinal plane measured through ultrasonography from different sites: a comparison study. europepmc.org 2014; 53: 880–883
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- Not Yet Recruiting
- Sex
- All
- Target Recruitment
- 40
Adult patients (Age > 18 yrs ) Acute circulatory failure Receiving protective lung ventilation ≤ 6ml/kg IBW using Volume Assist Control mode, without any spontaneous activity Need of prone ventilation as decided by treating physician.
- Acute myocardial infarction Previously known significant valvular disease or intracardiac shunt Air leakage through chest drains Right heart failure An urgently required fluid challenge.
- Abdominal compartment syndrome, and pregnancy Raised intracranial hypertension Recent Abdominal surgery.
Study & Design
- Study Type
- Interventional
- Study Design
- Not specified
- Primary Outcome Measures
Name Time Method To determine whether the change in Inferior Vena Cava distensibility index  in lateral approach during “tidal volume challenge†can reliably predict fluid responsiveness in patients ventilated in prone position   at baseline
- Secondary Outcome Measures
Name Time Method To determine whether Inferior Vena Cava -Distensibility index in lateral approach has good correlation and agreement during tidal volume challenge in supine and prone positions immediate To determine whether Inferior Vena Cava distensibility index in subxiphoid and lateral approach has good correlation and agreement during tidal volume challenge baseline
Trial Locations
- Locations (1)
St Johns Medical College Hospital
🇮🇳Bangalore, KARNATAKA, India
St Johns Medical College Hospital🇮🇳Bangalore, KARNATAKA, IndiaNatesh Prabu RPrincipal investigator08022065334drnateshrprabu@gmail.com