The results of monitoring the physiological function of the patient using various instruments are the basis for decision-making to enhance treatment in the ICU. Due to the rapid development of modern science and technology and the integration of multiple disciplines, new instruments and equipment continue to enter the field of monitoring, these devices set of modern mechanical, electronic, microcomputer and sensing technology in one, it is necessary to achieve complete proficiency.
The interpretation of the test results should be comprehensive and reasonable, to fully consider the limitations and constraints of each monitoring, pay attention to the study of the same system of different indicators and the link between different systems to prevent one-sidedness. For example, the heart and lungs are very closely related organs both anatomically and functionally, and when a report of low arterial partial pressure of oxygen is obtained, in addition to the impairment of lung function, a decrease in cardiac output should be ruled out at the same time. When cardiac and pulmonary function are in a borderline state, even without further deterioration of pulmonary function, poor arterial blood gas results can be caused by a decrease in cardiac output, which is associated with a decrease in the partial pressure of mixed venous blood oxygen and intrapulmonary shunting. Disease is a continuous pathologic process, and therefore continuous and dynamic observation should be emphasized; isolated data, even if seemingly "abnormal," are not sufficiently descriptive, as exemplified by the monitoring of circulatory pressures. Although a series of normal values have been established for central venous pressure (CVP), right atrial pressure (RAP), pulmonary artery wedge pressure (PAWP), etc., volume overload or cardiac insufficiency cannot simply be judged on the basis of a high CVP, RAP, or PAWP, because critically ill patients usually have decreased cardiovascular compliance, thus diminishing the reliability of the normal pressure values in reflecting volume and cardiac status. The reliability of normal pressure values in reflecting volume and cardiac status is undermined. In this case, even low volumes and insufficient ventricular filling may indicate high pressure values, and continuous ambulatory monitoring of heart rate, pressure, and cardiac output, supplemented by a volume-loading test if necessary, is necessary to identify this.
A rational treatment plan should be developed based on the detailed monitoring information obtained. When analyzing and applying this information, it is important to look at the changes in the body in a pathological state dialectically rather than metaphysically, and essentially rather than superficially. We often find that many indicators such as cardiac output, oxygen consumption, ventilation, metabolism, etc., are elevated and "abnormal". This "abnormality" is a reflection of the disease, but at the same time reflects the sound adaptive and compensatory capacity of the body. Therefore, the correct approach to such changes is to protect them rather than artificially suppressing them and forcing them back to "normal", unless the reaction is too drastic and may cause new damage. We should be clear that the so-called "normal value" can only be used for normal people, it does not indicate the normal response in the state of disease, if in serious diseases, those parameters reflecting the measurement of compensatory function are still shown as "normal", it is likely to indicate that the patient's compensatory function is insufficient. If the parameters reflecting compensatory function are still "normal" in severe disease, it is likely that the patient's compensatory function is insufficient, and this is the real cause for concern. It is also important to understand that surgical patients are different from medical patients in that organ failure in the latter is often primary, whereas in the former it is often secondary and is primarily the result of shock, hypovolemia, or severe infections, and therefore prevention is the main therapeutic task, which makes the infusion of fluids and medications in surgical patients usually much more aggressive.
Currently, there are emerging issues with physiologic monitoring, such as the fact that some of the more important and precise monitoring cannot yet be completely noninvasive and has the potential to damage tissue and induce infection. Therefore, the pros and cons of any invasive monitoring should be weighed and simple and non-invasive monitoring systems should be used as much as possible without compromising observation and treatment. In addition, modern monitoring is only an extension and supplement to traditional means of observation and examination, and although they can detect many things that humans cannot with their eyes and other senses, they are still sometimes not a substitute for traditional methods. For example, heart valve lesions can alter the interpretation of certain information about hemodynamics; pneumothorax can make shock difficult to resuscitate, and so on. Physiologic monitoring is sometimes difficult to detect these problems, yet they are easily confirmed by simple physical examination. In conclusion, while we fully recognize the advancement and superiority of ICUs and rigorous physiological monitoring, we should also see its limitations and shortcomings, so that we can make use of our strengths and avoid our weaknesses. In fact, although some ICUs have the same instrumentation and medical conditions, the treatment results are so different that we can still see very different evaluations of ICUs.