The measurement, recording, and reporting of vital signs are integral to patient management. These findings vary in disease and provide immediate information for the experienced healthcare professional about the underlying pathology. In addition, comorbidities give information on the patient’s prognosis and lead to different ways of patient management. The study showed the importance of vital signs such as DBP and comorbidities in determining a patient’s emergency status, such as MECs.
The oxygen saturation expresses the percentage of hemoglobin molecules saturated with oxygen. This indicates the state of hypoxemia. As in our study, hypoxia carries a risk for mortality, and mortality rates increase as hypoxia deepens (6, 14). It is a marker for hospitalized patients' intensive care unit (ICU) admission (15). The low oxygen saturation value before discharge is even significant for re-admission to the ED (9, 12). Diastolic blood pressure is the resting pressure on the arteries between each cardiac contraction. Low DBP causes high pulse pressure, and increased pulse pressure may indicate arterial stiffness, often due to aging or cardiovascular disease. High diastolic blood pressure causes low pulse pressure, which may be a marker of poor heart function with decreased cardiac output. Although not mentioned in the literature, which is similar to our study (9, 12, 14), low DBP can predict mortality (6); it has even been shown that low DBP is a better predictor of cardiac arrest (16). Even though high DBP was not found significant in predicting the emergency status in the study, Bleyer et al. showed an increase in mortality at values of 120–130 mmHg and above for DBP, unlike our study (6). Systolic blood pressure is the maximum pressure on the arteries during left ventricular contraction. Low SBP causes low pulse pressure, a marker of poor heart function, and reduced cardiac output. On the other hand, high SBP may be due to renal, endocrine, intracranial, pregnancy-related, and cardiovascular causes, as well as essential. In the study, low and high SBP was not statistically significant in predicting the MEC. Contrary to the survey, low SBP was a risk factor for mortality, and mortality rates increase as the low SBP deepens (6, 14). The low SBP before discharge resulted in re-admission to the ED and mortality (9, 12). An increase in mortality was found at values of 200 mmHg and above for SBP (14).
Respiratory rates vary with age. The average resting RR for adults is 10–20 breaths per minute. An increased number of breaths carries a significant risk for mortality, and mortality rates increase as tachypnea worsens (6, 14). A high RR before discharge is a good indicator for re-admission to the ED. As the number of breaths increases, the transfer rates of hospitalized patients to the ICU and mortality increase (12, 16). Heart rate is an important variable that determines cardiovascular risk. Tachycardia is a resting HR above 100 beats/min in adults. Tachycardias may occur due to physiological processes such as effort, anemia, pain, and anxiety. It may also arise for compensation in pathological processes such as hypoxia, fever, acidosis, hyperthyroidism, shock, and coronary ischemia. A heart rate below 60 beats/minute is bradycardia in adults except for athletes (17). A high HR is significant for mortality; the mortality rates increase with an increase in heart rate (6, 14). Tachycardia is a good indicator of in-hospital cardiac arrest, and a high heart rate before discharge increases the re-admission to the ED (9, 12, 16). While low heart rate was not statistically significant in predicting emergencies in the study, an increase in mortality was found in low heart rates (14). Body temperature is a vital sign affected by many internal and external sources. A healthy person's body temperature ranges from 36.5 to 37.8° C. Like the study, Nguyen et al. did not find an increase in re-admission to the ED and 30-day mortality with high body temperature before discharge (12). However, there are also studies showing an increase in mortality as the body temperature increases, and there is an increase in re-admissions to the ED in patients with high body temperature before discharge (6, 9, 14). Current findings have not clarified the role of body temperature in predicting an emergency status. Bleyer et al. classified the comorbid diseases of the patients as chronic heart failure, chronic obstructive pulmonary disease, cancer, dementia, end-stage renal disease, and other end-stage diseases. Similar to our study, there was no mortality risk in the presence of chronic heart failure or dementia. Still, an increased mortality risk was observed in end-stage renal and other end-stage diseases (6). It has been shown that the vital signs and comorbidities affect mortality, transfer to the ICU, and the frequency of re-admissions to the ED (6, 9, 12, 14, 15). Charlson Comorbidity index skoru arttıkça mortalite ihtimalinin de arttığı görülmüştür (18, 19). It is also recommended that comorbidities be used to determine trauma patients' initial triage and prognosis. (20). It is seen that the importance of comorbidities in terms of triage is underestimated, especially in elderly trauma patients. (21). Likewise, it is reported that comorbidities should be considered to predict the prognosis after surgery (22, 23). Even an artificial intelligence-based triage system was created in which comorbidities were encountered. (24). Although there are similar studies, the difference in the outcome part and the calculation of the emergency risk based on comorbid diseases are the most valuable aspects of the study.
Limitations
There are some limitations in the study. It was a single-center study with the patient population of a single region. Other limitations in the study are that other early warning systems, triage grading, and re-measurements of vital signs were not evaluated.