Volume 5 Supplement 4

18th Autumn Meeting of the Association of Cardiothoracic Anaesthetists

Open Access

Oesophageal Doppler monitoring of descending aortic blood flow velocity during off-pump coronary artery bypass surgery

  • SK Kodakat1,
  • M Delaguila1,
  • U Trivedi1 and
  • R Kong1
Critical Care20015(Suppl 4):8

https://doi.org/10.1186/cc1440

Published: 7 November 2001

Objective

Acute haemodynamic changes occur frequently during off-pump coronary artery surgery (OPCAB). Currently used haemodynamic monitors are not satisfactory during this procedure. We assessed the feasibility of oesophageal Doppler insonation of the descending aorta to measure cardiac output and other haemodynamic indices continuously during OPCAB.

Methods

Twenty-five consecutive patients scheduled to undergo OPCAB were studied prospectively. The ethical committee waived the need for informed consent because the oesophageal Doppler monitor (CardioQ, Deltex, UK) was already in routine use in our hospital. Haemodynamic parameters were recorded at multiple intervals after anaesthetic induction; before sternotomy; before, during and after each anastomosis and at the end of surgery. Stroke volume, cardiac output (CO), corrected flow time (FTc), peak velocity(PV) and mean acceleration were measured or calculated by the Doppler monitor. Mean arterial pressure (MAP) and central venous pressure(CVP) were measured from radial artery and internal jugular venous cannulae respectively.

Results

Satisfactory Doppler signals were not obtained in one patient. Two patients were converted to standard revascularisation using cardiopulmonary bypass because of technical considerations. One, 7 and 14 patients had one, two and three vessels grafted respectively. The haemodynamic data on these 22 patients are presented in Table 1 as mean and standard deviation.

Table 1

 

CO (l/min)

MAP (mmHg)

CVP(mmHg)

FTc (s)

PV(cm/s)

Post Induction

4.28 ± 1.30

78 ± 21

 

325 ± 44

50 ± 12

Pre LAD

5.12 ± 1.41

72 ± 17

8 ± 4

355 ± 29

54 ± 17

During LAD

4.76 ± 1.26

68 ± 13

10 ± 4

353 ± 45

53 ± 16

Post LAD

5.57 ± 1.68

71 ± 15

9 ± 5

359 ± 45

55 ± 16

Pre Cx

5.46 ± 1.84

67 ± 12

13 ± 5

353 ± 60

53 ± 17

During Cx

4.19 ± 1.12

68 ± 10

16 ± 5

343 ± 50

48 ± 12

Post Cx

5.67 ± 1.69

70 ± 13

7 ± 4

375 ± 56

57 ± 13

Pre PDA

5.38 ± 1.39

83 ± 17

12 ± 4

375 ± 42

52 ± 17

During PDA

5.38 ± 1.15

73 ± 13

14 ± 3

355 ± 61

54 ± 16

Post PDA

5.14 ± 1.19

68 ± 13

9 ± 4

356 ± 39

53 ± 16

Chest closed

4.89 ± 1.34

67 ± 12

9 ± 3

338 ± 40

57 ± 15

LAD (left anterior descending artery) = 21 patients, Cx (circumflex artery) = 18 patients, PDA (posterior descending artery) = 15 patients. Pre, during and post refer to immediately before, during and after anastomosis.

Conclusion

The oesophageal Doppler was able to monitor cardiac output and other haemodynamic parameters continuously throughout OPCAB. Further studies are needed to determine whether or not active haemodynamic management assisted by oesophageal Doppler monitoring during OPCAB improves patient outcome.

Authors’ Affiliations

(1)
Departments of Anaesthesia and Cardiac Surgery, Sussex Cardiac Centre

Copyright

© BioMed Central Ltd 2001

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