Nutrients provide the body with the components necessary for effective functioning. Nutrients can be broken down into macronutrients, such as proteins, fats, and carbohydrates, and micronutrients, such as vitamins, provitamins, and various minerals. A shortage of any of these nutrients can result in nutritional deficiency within the body, affecting its ability to maintain functioning.
“Modern medicine pays little attention to nutritional deficiencies in cardiac surgery patients. At the same time, in oncology, pediatrics, gastroenterology, nutrition is treated more closely. To remedy this situation, in 2011 we began a study that included the task of identifying the prevalence of nutritional deficiency among those who underwent cardiac surgery,” said lead author Sergey Efremov, an anesthesiologist-resuscitator, head of the research department at the Pirogov Clinic of High Medical Technologies, St Petersburg State University, in a press release.
In patients with severe cardiac failure, the extreme emaciation of the body is a potential result and has been termed cardiac cachexia. The reasons for such emaciation include low cardiac output or a response to drugs that suppress appetite. The symptoms of cardiac cachexia in patients can be physical weakness and rapid weight loss, resulting in a lack of nutrients in the body.
“The problem is also complicated by the fact that most often patients with such a diagnosis do not appear to be starving. Oedema may even make them seem overweight. That is why it was of paramount importance for us to find a reliable tool for identifying this condition,” Efremov said in the press release.
Over a period of 8 years, researchers monitored approximately 1000 patients who underwent cardiac surgery. Following their admission to the clinic, they were given a questionnaire to complete in order to determine their nutritional status.
Using a set of indicators, the researchers were able to characterize patients’ quantitative ratio of muscle to fat mass. Additionally, preoperative and postoperative data were gathered on the participants. Following 1, 3, and then 8 years, patients were queried about their current health.
“As a result of the study, we have found that the patient's nutritional status has an important prognostic value, since it enables us to identify the postoperative complication rate. As expected, the higher the degree of nutritional deficiency, the higher the probability of a negative scenario. Additionally, we have managed to identify a small group of cardiac surgery patients who are more susceptible to this condition. These are the patients with valvular heart disease,” Efremov said in the press release.
According to Efremov, several scales currently exist that help to assess patients’ nutritional status, but none are specifically designed for patients with cardiovascular pathology. Using the Malnutrition Universal Screening Tool (MUST) scale, the researchers were able to assess study participants’ nutritional status with greater sensitivity and specificity.
The researchers noted that the MUST scale can be introduced into the quotidian practices of clinics, allowing any health care worker to assess the patient's condition with greater clarity. If the scale demonstrated that patients have malnutrition, a physician can step in to ask further questions about the status of the patient's nutritional health.
“The Pirogov Clinic has recently become a part of St Petersburg University. And for us, its employees, it is very important to integrate with other departments of the University within the framework of project activities. That is why I am very pleased that students from the Faculty of Medicine at St Petersburg University took part in this research. They were actively engaged in collecting, systematizing, and analyzing data. Largely thanks to their contribution, it became possible to complete this study,” Efremov said in the press release.
The researchers also plan to do further investigation into solutions that could ameliorate the condition of patients with nutritional deficiencies. Specifically, they intend to look at the efficacy of different clinical nutritional formulas for patients following cardiac surgery.