View the wider picture in patient monitoring

Randomised trials1 have shown that improved monitoring and protocolised therapy can drive a reduction in postoperative complications in high risk surgeries by up to 40% and enable patients to leave hospital, on average 12 days earlier than those patients treated with the use of conventional care. A report by the National Confidential Enquiry into Patient Outcome and Deaths in the UK (2000)2 recognised that patients who die after surgery are more likely to be elderly, have coexisting medical disorders and require urgent or emergency surgery. The data showed that there was a group of surgical patients whose post-operative mortality is 20% to 30%, compared to the surgical population as a whole whose mortality is 0.8% to 1%. This high-risk group of surgical patients is associated with over 25,000 deaths within 28 days of surgery each year in the UK (excluding Scotland). A significant improvement in surgical outcomes can only come from targeting this group, according to Dr Max Jonas, consultant anaesthetist and intensivist.3 He observed that what makes this group so vulnerable appears to be the inability to mount an appropriate physiological response to major surgery. Poor cardiorespiratory performance results in a failure to increase oxygen delivery in response to surgical stress, which can lead to cellular hypoperfusion and anaerobic metabolism – thereby generating an “oxygen debt” that can result in patient mortality.3 He suggested that the speed at which this debt is repaid determines not only the likelihood of death, but also the incidence of complications – such as infection and multiple organ failure in survivors. This concept has become the basis for the strategy of goal-directed therapy and has been emphasised by a series of observational studies. Shoemaker4 initially defined the criteria that were associated with a poor prognosis and then showed that the ability to measure and increase oxygen delivery within this higher-risk group gave dramatic benefits, reducing mortality from 33% to 4%.

The concept of “goal-directed therapy” subsequently emerged and is evolving with a rapidly growing evidence base.3 “The underlying premise is that the use of intravenous fluids – and possibly inotropes and vasoactive drugs – can restore or improve oxygen delivery to prevent, or more rapidly repay, outstanding oxygen debt,” Dr Max Jonas explained.3 “Patient selection appears critical, with a focus on targeting those with the specific comorbidities considered to increase mortality significantly (?20%). Similarly, successful intervention requires timely involvement prior to there being evidence of end organ derangement. The accumulated evidence suggests that reductions in mortality were only found in studies where haemodynamic goals were targeted using fluid and inotropes, but that may be because none of the intraoperative fluid studies have been powered for mortality,” he continued.3 What the intra-operative studies have shown is that targeted fluid administration results in a decreased length of hospital stay because of a reduction in postoperative complications, such as infection. The recognition of hypovolaemia and oxygen flux derrangement, and the prompt restoration of homeostasis, need to be monitored as the potential to cause harm from inappropriate therapy has been clearly demonstrated in various studies.5

The more accurate and better focused the monitoring, the more clinicians are able to target interventions and assess their effects. By harnessing technology developed in consumer electronics and adapting this to meet the very specific demands and culture of healthcare, medical specialist Lidco has been able to produce a cardiac monitoring solution to enable operating theatre teams to see the total picture of changes and reactions of a patient’s cardiovascular system on one monitor. Dr Terry O’Brien, CEO of Lidco commented: “We know that practical considerations are vital inside an operating theatre. When clinicians are asked what they want from their equipment, they will universally agree it has to be unobtrusive, easy to use, quick to set up and simple to integrate with existing equipment. With the Lidco Rapid system, surgeons and anaesthetists have the ability to monitor and view the patient’s various vital signs parameters simultaneously, in real-time. “This provides the earliest warnings if fluid or drugs levels need to be adjusted. It is the first time all this inter-dependent information has been available on one machine with a graphical user interface (GUI) specifically designed for surgery. The ability to run this software and present a more evolved GUI is due to the increased capacity available from the processor, coupled with strong partnerships with suppliers such as Display Solutions to meet the exacting demands of the surgical applications we are addressing. “Basically, if patients can be optimised there are real differences that can be achieved in surgery. By providing simultaneous information to clinical staff you are presenting them with a much more informed picture of what is happening with the patient.” The system displays essential parameters, including the following: