"We need to individualise our care to the patient in front of us, being responsive to his/her physiological requirements at the moment in time, and adapting as the situation changes."
Professor M. Singer is professor of Intensive Care Medicine at University College London, UK. He was recently awarded UK National Institute of Health Research (NIHR) Senior Investigator status for the period 2009-12.
1. Some words about yourself?
Professor of Intensive Care Medicine at University College London, UK. Recently awarded UK National Institute of Health Research (NIHR) Senior Investigator status for the period 2009-12. I was heavily involved in the development of the CardioQ oesophageal Doppler haemodynamic monitor and have been actively involved in the development of monitors of tissue perfusion. I was Principal Clinical Investigator of the PAC-Man trial (Harvey et al, Lancet 2005), a major, multicentre UK trial assessing the impact of the pulmonary artery catheter on patient outcomes in intensive care.
2. Which has been the last International meeting you have attended?
29th international Symposium on Intensive Care and Emergency Medicine, Brussels
3. In one of your paper, you talk about the heterogeneous of intensive care practice. Any comment regarding patient monitoring?
There’s a huge variability in current practice, in large part related to a lack of a decent evidence base to direct us as to how, when and with what to monitor.
The other contentious issue I have is that many clinicians lack an adequate understanding of physiology and pathophysiology, and thus clear insight of how to best manage the patient. It’s not simply about making the numbers look ‘normal’ or driving every patient parameter to fall within a certain range. We need to individualise our care to the patient in front of us, being responsive to his/her physiological requirements at the moment in time, and adapting as the situation changes. This knowledge problem is also reflected in a general ignorance of what monitors can and can’t offer in different conditions, and their shortcomings. As a consequence, erroneous decisions can be taken to the possible detriment of the patient.
4. Do you consider intraoperative intravascular volume optimisation to be of great value. The question is: to all kinds of surgery?
Absolutely! There is a clear biological rationale in that surgery represents an inflammatory hit which is amplified in the presence of tissue hypoxia. The commonest cause of the latter is tissue hypoperfusion related to hypovolaemia. It is thus beholden upon us to make sure the patient isn’t fluid-deplete, though we must also take care to not go too far in the opposite direction. The message is neither too dry nor too wet, but just right!
As to all types of surgery, clearly a minor operation which represents a small ‘hit’ doesn’t mandate excessive efforts to optimize the circulation. However, even relatively minor surgery can result in nausea and vomiting, gut dysfunction, impaired wound healing and malaise which studies have shown can be significantly ameliorated by fluid. In summary, all kinds of surgery would benefit though the degree of monitoring needs to be guided depending on the extent of surgery and the underlying health of the patient.
5. If I had to buy one system for cardiac output control in the perioperative setting, any suggestion? Why?
I’m obviously biased but I would pick the CardioQ oesophageal Doppler system! Why? Pulmonary artery catheterisation is diminishing in popularity due to its invasiveness and attendant risks. Of the alternatives, CardioQ is by far the best validated in terms of monitoring and trend following, and by far the best validated in terms of showing patient outcome benefits. Nine separate studies in patients undergoing abdomino-pelvic, cardiac, orthopaedic and trauma surgery have all consistently shown reductions in complications and thus ICU or hospital stay from Doppler-guided fluid optimization. Competing technologies cannot compete with this track record; indeed, the findings that have been published to date are both scanty and far less consistent/impressive. The oesophageal Doppler is, however, of less value during oesophageal surgery and during cross-clamping of the aorta.
6. Do you agree with those that are including goal-directed perioperative fluid therapy in Fast Track protocols?
Yes. It’s a logical part of the package.
7. One big concern in medical care is cost. Is this type of monitoring cost-effective?
Clearly, an extra day in hospital results not only in extra cost but also decreased efficiency as that bed is effectively blocked. If 3-4 day reductions in hospital stay can be achieved through perioperative fluid optimisation, that represents a significant saving, well offsetting the relatively minor costs of the monitoring and some extra fluid.
8. Could esophageal Doppler avoid any traditional measurement?
Central venous monitoring becomes less necessary for fluid optimisation though it does have its uses for measuring central venous oxygen saturation
9. According to you, in which patient is mandatory the transesophageal Doppler ultrasound?
Those who are either unstable pre-operatively, or those at high risk of developing instability, e.g. expected major blood loss, and/major co-existing morbidity such as severe heart failure.
10. How has the care of patient changed because of this improvement in monitoring?
To my mind, it allows the correct amount of fluid to be given, i.e. not too little and not too much. So we see fewer ‘crispy’ patients and fewer’ Michelin men’ and I think patients benefit as a consequence
11. If you were the manufacturer, how would you improve the machine?
Develop a ‘smart probe’ so the machine can auto-focus
12. Lastly, could you give us your opinion about www.ftsurgery.com?
Impressive. It’s clear and informative. I hope there will be lots of constructively critical articles as we really need to keep challenging the dogma and our long-held, but often mistaken, beliefs.