Oesophageal Doppler Monitoring (ODM) provides a non-invasive assessment of stroke volume and cardiac output during surgery. A randomized controlled trial found that using ODM to guide intraoperative fluid management in colorectal surgery patients resulted in shorter hospital length of stay, earlier return of gut function, fewer complications, better hemodynamic measurements, and cost savings compared to managing fluids to maintain CVP between 12-15 mmHg. ODM may help optimize fluid management and improve recovery in complex and orthopedic surgeries.

2. Worthing

8. 25-30% Haemorrhage in Man 2 1 0 1 2 0 1 8 0 1 5 0 9 0 6 0 3 0 B a s e H e a r t r a t e S y s B P T i m e ( m i n u t e s ) 8 0 0 m l 8 0 0 m l Hamilton-Davies et al Intensive Care Med 23(3):276-281,1997 Controlled haemorrhage Re-transfusion 0 2 0 4 0 6 0 8 0 1 0 0 1 2 0 1 4 0 1 6 0

9. 25-30% Haemorrhage in Man Hamilton-Davies et al Intensive Care Med 23(3):276-281,1997 Controlled haemorrhage Re-transfusion Base 800ml 800ml Gastric pHi 7 . 0 0 7 . 0 5 7 . 1 0 7 . 1 5 7 . 2 0 7 . 2 5 7 . 3 0 7 . 3 5 7 . 4 0 7 . 4 5 T i m e ( m i n u t e s ) a e m o r r h a g e 2 1 0 1 2 0 1 8 0 1 5 0 9 0 6 0 3 0

12. Frank Starling Curve Cardiac Function Curve Oesophageal Doppler Monitoring Stroke Volume End-Diastolic Volume  < 10%  > 10%  0%

13. Useful Extrasystole

22. Patient characteristics Control Median (IQR) Protocol Median(IQR) Age (years) Mean (sd) 69.6 (10.2) 69.1 (12.3) Physiological Possum 18 (7.0) 17 (6.5) Operative Possum 16 (9.0) 15.5 (7.0) BMI 26 (7.25) 24.5 (6.75)

23. Operative data Control Median(IQR) Protocol Median(IQR) Blood loss (ml) 500 (975) 500 (700) Per-operative crystalloid (ml) 3000 (1187) 3000 (1750) Per-op. colloid * (ml) Range 1500 (0 – 4000) 2000 p<0.001 (500-5000 ) Urine output 1 st 36 hours * 2754 (1453) 3649 (2000) p<0.01

24. Haemodynamic data Control Median (IQR) Protocol Median(IQR) Stroke Volume (ml) p<0.001) 77 (25) 99 (43) * Cardiac Output (l.min -1 ) p<0.02 5.6 (2.9) 7.25 (2.37) * Oxygen Delivery (ml.min.m 2 ) p<0.011 445 (200) 535 (229) *

25. Haemodynamic data Control Median (IQR) Protocol Median(IQR) CVP overall (mmHg) 13 (5) 14 (5) CVP End of surgery (mmHg) 13 (5.5) 13 (4.5)

26. Post-operative Progress Control Median (IQR)days Protocol Median (IQR)days Flatus passed 4 (2) 3 (2) Bowels open 5 (2) 4 (3) Full diet 7 (2) 6 (2) Discharge 11.5 (4.75) 10 (5.75)

27. Kaplan-Meier Plot

29. Serum endotoxin levels

30. Intestinal Permeability

36. IPPV IPPV & PEEP HEAD DOWN Reliable CVP? HEAD UP

37. Haemodynamic values at start and end of surgery