After receiving approval from the institutional ethics committee, one patient

will be selected per day by simple random sampling from total number of major

surgeries posted the day. Major surgeries are defined as surgeries whose duration is

likely to exceed two hours. Written informed consent will be obtained from the

patient after sharing the information about the study.

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Pre-operative baseline trans thoracic echo (apical 4 chamber view) will be

performed in left lateral position on the selected patient using Sonosite Xporte

ultrasound machine with P21xp (1-5MHz) cardiac probe in the preoperative holding

area to record the base line Echo parameters quantifying left ventricular systolic

function (ejection fraction) and diastolic function (E, A, E/A, Septal/lateral e/, E/e/,

LA Volume index, TR velocity). If the patient has poor echo-cardiographic window

in left lateral position, ECHO will be repeated in supine position and subsequent

measurements for the patient would be taken in the same position( left lateral/

supine) where good echo cardiographic window is obtained. If the patient has left

ventricular systolic dysfunction or if the echo cardiographic window continuous to be

poor, the patient will be excluded from the study. Another patient from study

population will be selected as per the detailed procedure described above for

inclusion in the study. To maintain accuracy in measurements, all transthoracic-echo

parameters will be recorded by both the investigator and the echo-cardiographer until

the time the investigator recorded values are consistent with echo-cardiographer

values.

After recording the baseline parameters, the patient will be shifted into

operating theatre and standard monitoring will be established with SPO2, ECG,

NIBP/IBP, EtCO2, temperature and urine output measurement. The anaesthetic

technique will be as per the decision of the attending anaesthesiologist.

All the TTE measurements will be done in left lateral position/ supine position

(position in which baseline recordings are done) as per the description below.

1. If the choice is TIVA (Total intravenous anaesthesia) with propofol, the

measurement will be done one minute after induction.

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2. If the choice is inhalational anaesthesia, the measurement will be done after

obtaining steady state 1 MAC anaesthesia with Isoflurane/sevoflurane

/Desflurane.

3. If the choice is intravenous induction followed by inhalational anaesthesia,

one measurement will be done one minute after intravenous induction with

propofol and second measurement after obtaining steady state 1 MAC

anaesthesia with Isoflurane/sevoflurane /Desflurane.

4. If the choice is regional anaesthesia combined with general anaesthesia, the

measurement will be taken after establishing both.

5. If the choice is spinal, the measurement will be taken 10 minutes after spinal.

6. If the choice is epidural, the measurement will be taken 20 minutes after

epidural.

7. If the choice is peripheral nerve block, the measurement is taken after

establishing complete block.

During intermittent positive ventilation, measurement will be taken during

expiratory phase, if necessary by prolonging it, by not initiating the next breath.

During anaesthesia, the SpO2, ECG, NIBP, EtCO2 and temperature will be monitored

continuously. Care will be taken to maintain fluid balance and blood will be replaced

as per requirement. The temperature will be maintained above 36*C all the time, if

needed by active warming methods. Normocarbia will be maintained by adjusting

ventilation under general anaesthesia. Hypoxemia will be prevented by administering

O2 by mask for the patients under regional anaesthesia. Blood pressure will be

maintained within 20% of baseline by using appropriate methods. Hourly urine

output will be monitored