- Email: [email protected]
Evaluation of the Acute Physiology and Chronic Health Evaluation III in predicting the prognosis of patients admitted to Emergency Department, in need of intensive care unit
American Journal of Emergency Medicine (2012) 30, 1141–1145
www.elsevier.com/locate/ajem
Original Contribution
Evaluation of the Acute Physiology and Chronic Health Evaluation III in predicting the prognosis of patients admitted to Emergency Department, in need of intensive care unit Hamid Reza Hatamabadi MD a, b , Parvin Darbandsar Mazandarani MD a,⁎, Ali Abdalvand MD a , Ali Arhami Dolatabadi MD a , Afshin Amini MD a , Hamid Kariman MD a , Hojjat Derakhshanfar MD a a
Department of Emergency Medicine, Imam Hosain Hospital, Shahid Beheshti University of Medical Sciences, Tehran 1617763141, Iran b Intentional Injury Unit, Safety Promotion and Injury Prevention Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran Received 18 May 2011; revised 4 August 2011; accepted 5 August 2011
Abstract Introduction: Many of critically ill patients receive medical care for prolonged periods in emergency department (ED). This study is the evaluation of efficiency of Acute Physiology and Chronic Health Evaluation (APACHE) III scoring system in predicting mortality rate in these patients. Methods: This study was conducted between 2008 and 2009 in Tehran, Iran. One hundred subjects were enrolled in the study. Cases were chosen from patients in need of intensive care unit (ICU) bed who were kept in the ED. The APACHE III scores and predicted and observed mortality rates were calculated using the information from patients' files, interviews with the patients' families, and performing required physical examinations and laboratory tests. Results: The age of the patients and the ED length of stay were 66.07 (±19.92) years and 5.11 (±3.79) days, respectively. The mean (±SD) of APACHE III score of the patients was 58.89 (±18.24). The predicted mortality rate was calculated to be 32.73%, whereas the observed mortality rate was 55%. The mean (±SD) of APACHE III score of survivors and nonsurvivors was 48.63 (±16.35) and 67.63 (±14.84), respectively (P b .001). Furthermore, the ED length of stay was 3.20 (±1.34) and 6.57 (±4.4) days in survivors vs nonsurvivors, respectively (P b .001). Conclusion: The APACHE III score and ED lengths of stay were higher in this study compared with other studies. This could be ascribed to more critical patients presenting to the study center and also limited ICU bed availability. This study was indicative of applicability of APACHE III scoring system in evaluating the quality of care and prognosis of ED patients in need of ICU. © 2012 Elsevier Inc. All rights reserved.
1. Introduction ⁎ Corresponding author. Tel.: +982173432380; fax: +98 2177557069. E-mail address: [email protected] (P. Darbandsar Mazandarani). 0735-6757/$ – see front matter © 2012 Elsevier Inc. All rights reserved. doi:10.1016/j.ajem.2011.08.005
The increasing number of patients and limitations in treatment facilities has brought up the need for an optimum
1142 allocation system for medical services. This need is even more seriously felt in the case of specialized medical services such as intensive care units (ICU) [1]. Based on the data from the United States published in 1982, 40% of patients admitted to the ICU were not admitted properly. That is, either their condition was so poor that even intensive care did not benefit them and did not reduce their mortality or morbidity or their condition was not critical enough to be admitted to the ICU in the first place [2]. Nowadays, physicians as well as patients require guidelines to follow for admission, care, and discharge from ICU, based on updated scientific research and technology [3]. Knaus et al [4] introduced the “Acute Physiology and Chronic Health Evaluation” (APACHE) system in 1981 to classify disease severity and predict future events in the course of disease. Further studies by the same group led to the development of APACHE III in 1991. In this system, data are gathered from patients, which include 16 different physiologic variables, age, history of chronic diseases, final diagnosis, and place of admission before transfer to the ICU. Manyofthepatientsinneedofintensivecareareadmittedand givencareinemergencydepartment(ED),forextensiveamount of time because of limited bed availability in the ICUs [5-8]. Therefore,technicalsupportandimprovementofEDpersonnel trainingarenecessarytoenhancethequalityofcareforpatientsin need of intensive care before their admission to ICUs. Furthermore, a diagnosis cannot be made during the first visit in many cases. In these cases, patients should be admitted and observedintheEDforawhilebeforeadiagnosiscanbemadeand thepatient betransferred to ICU.Another group ofpatients who are often admitted in the ED are unstable patients who cannot be admittedinthegeneralwardsofthehospital,thus,needtobecared andtreatedinEDwhilewaitingforavacantbedinICU[9,10].The aforementionedissuesledtothedevelopmentofanobservation unit in or adjacent to the EDs [11,12]. Several studies have evaluated the efficiency of the APACHE III system as a tool to evaluatethequalityofcareintheICUs[13-15]. In the ED of Imam Hosain Hospital in Tehran, Iran, emergency medicine specialists and residents look after the patients who are in need of ICU beds admitted to the ED. Based on current standards, the ratio of intensive care beds to regular beds should be 10% [16]. In Iran, this number is roughly 3%, and in Imam Hosain Hospital, 6% of the beds are ICU beds. Considering the current number of road accident casualties and heart disease victims (which are 2 main constituents of patients in need of ICU care in Iran [17]), there is a serious shortcoming in number of ICU beds. Unfortunately, Iran has the first place in the number of traffic accidents and annual death from road accidents (30 in 100 000 cases) [17-19]; thus, the need for increasing intensive care beds of the ED for observation is inevitable. The primary aim of the present study is to evaluate the efficiency of APACHE III system in predicting patient mortality in the ED. The second aim is to evaluate the quality of care that patients received in the ED by comparing predicted mortality rate with observed mortality rate in these patients.
H.R. Hatamabadi et al.
2. Materials and methods This cross-sectional, analytic study was conducted between March 2008 and March 2009 in the ED of Imam Hosain hospital, Tehran, Iran. This hospital is a tertiary center, which is a teaching hospital with 36 000 annual patient admissions and 450 beds, 21 of which are ICU beds and 30 are ED beds. The study group was patients who were diagnosed with an unstable condition in the ED on admission and in need of ICU bed based on the primary survey, clinical evaluation, and laboratory studies. The patients were followed up until they were either transferred to ICU or died. Inclusion criteria were patients who were visited in the first 6 hours of their admission by an ICU fellow and were candidates for admission to ICU but had to be cared for in the ED because of the lack of free beds in ICU. Exclusion criteria were being younger than 15 years, death within 4 hours of admission, and a lack of definite diagnosis before death. The number of subjects registered was 100, and the sampling was a nonprobability convenience method. This study was approved by the ethics committee of the participating hospital research center. The study variables were composed of (1) demographic data of the patients; (2) primary diagnosis; (3) comorbid medical problem; and (4) vital signs and physiologic indices in the first 24 hours of admission including heart rate per minute, respiratory rate per minute, body temperature (degree Celsius), mean arterial pressure (millimeters of mercury), arterial oxygen pressure (PaO2), or alveolar-arterial oxygen tension difference [PO(A-a)], blood hematocrit percentage, white blood cell count, urine output (milliliters per day), creatinine, blood sodium, bilirubin, albumin, glucose, blood nitrogen urea, and acid-base imbalance (pH and PCO2); (5) APACHE III score; (6) the length of hospital stay in the ED; (7) the number of observed deaths; and (8) the percentage of predicted mortality. In the case of repeated measurement of physiologic indices in the first 24 hours, the worst value was taken into account and recorded. At the same time, the indices, which were not measured, were scored zero. The data gathering was done through APACHE III questionnaire forms using the information in the patient's charts, interviewing the visitors, physical examination, and laboratory tests. The forms were completed either near to the end of the 24th hour of admission in the ED or latter hours of admission when the patient was transferred to the ICU in less than 24 hours. The data were analyzed using the APACHE III-J software and APACHE III score, and first-day mortality prediction (in percentage) was calculated. This software was updated in 1996 by studying 37 000 patients, and the final version is available at www.apache-web.com. SPSS version 11.5 (Chicago, IL) was used to analyze other data including demographic data, diagnosis, length of hospital stay, observed mortality, and its comparison to predicted mortality. Clinical indices were calculated and reported as mean ± SD,
Evaluation of the APACHE III Table 1
1143
Demographic characteristics of patients
Number enrolled in study
N = 100
Age (y), mean ± SD Sex Male Female ED length of stay (d)
66.07 ± 19.92
Nonsurvivors Age (y), mean ± SD Sex Male Female ED length of stay (d)
n = 55 74.93 ± 13.19
Survivors Age (y), mean ± SD Sex Male Female ED length of stay (d)
n = 45 55.24 ± 21.47
56 (56%) 44 (44%) 5.11 ± 3.79
28 (51%) 27 (49%) 6.57 ± 4.40
28 (62%) 17 (38%) 3.20 ± 1.34
and the Student t test was used for statistical analysis, with the α set to .05.
3. Results One hundred patients were eligible to enter this study, of which 55 died during their ED admission. The demographic data and length of hospital stay in both survived and deceased groups are shown in Table 1. Mean APACHE III score for the first day in all patients was 58.89 ± 18.24, and the predicted mortality was 32.73%. The mean APACHE III score, length of hospital stay, and age were significantly higher in the deceased group vs surviving group (P b .001) (Table 2). Among the patients in need of ICU who were admitted in the ED, the group with APACHE III score of 50 to 70 had the greatest prevalence. Fig. 1 shows the relation between APACHE III score and hospital mortality rate in each group. Comparison between predicted and observed mortality based on the APACHE III score indicates significant difference between these 2 in favor of the latter (Fig. 2).
Fig. 1 Relationship between APACHE III score and risk of hospital death.
This relation still follows the correlation between APACHE III score and mortality. Fig. 3 shows a linear correlation between predicted and observed mortality. Fig. 4 and Table 3 show the patient mortality based on the length of stay.
4. Discussion Since the introduction of APACHE III evaluation system by Knaus et al in 1991, its efficiency as a tool to evaluate expected mortality and quality of care in ICU has been studied several times in Iran and other places around the world [20]. The ever increasing number of patients in unstable condition in need of critical care has led to better provision of EDs with necessary equipments [21]. This, in turn, has raised the need for evaluation of the quality of care and its effect on the prognosis of patients. It has also necessitated the provision of further equipment and personnel training to EDs. The APACHE III system can be of great help in these kinds of evaluations, but its efficiency should first be confirmed.
Table 2 Mean APACHE III score, ED length of stay, and age in survivors vs nonsurvivors
APACHE III score, mean ± SD ED length of stay (d) Age (y), mean ± SD
Nonsurvivors
Survivors
P
67.63 ± 14.84
48.63 ± 16.35
b.001
6.57 ± 4.40 74.93 ± 13.19
3.20 ± 1.34 55.24 ± 21.47
b.001 b.001
Fig. 2 Expected and observed mortality rates based on APACHE III score.
1144
H.R. Hatamabadi et al. Table 3
Patients mortality based on ED length of stay
ED length of stay (d) ≤1 2-5 6-9 10-13 14-17 18-21 Total
Fig. 3
Risk stratification of mortality rate by APACHE III score.
In our study of 100 patients in the Imam Hosain hospital, the mean APACHE III score was 58.89 ± 18.24, whereas in 2 studies in Bou Ali Hospital (Tehran, Iran) and Imam Khomeini Hospital (Urmia, Iran), this score was shown to be 60.6 and 35.48, respectively [12,14]. This score has also been calculated and reported in other studies from United States (APACHE III score, 50), Japan (APACHE III score, 52.7), England (APACHE III score, 56.8), and South Korea (APACHE III score, 48.60) [21-23]. By comparing the scores, it could be implied that the patients in our study were generally having more severe problems. This could be due to the abundant number of patients who were referred to Imam Hosain hospital ED accompanied by the limited number of ICU beds available in the hospital. This combination has probably left the caregivers no other choice than to candidate patients for ICU admission in poorer conditions and with higher APACHE III scores. Furthermore, the patients in our study were older when means of age were compared with the aforementioned studies [16,24]. To the best of our knowledge, this study is the first of its kind in Iran. However, when we compared our results with a study from the United States that had used APACHE II scoring system [22], the differences were astonishing. The
Fig. 4
Patients mortality based on ED length of stay.
Nonsurvivors n
%
3 27 9 11 2 2 54
5.56 50 16.67 20.27 3.7 3.7 100
mean of hospital stay for patients in ED before being transferred to the ICU in our study was 5.11 ± 3.79 days, whereas it was 5.9 ± 2.7 hours in the aforementioned study, which is a large difference. In our study, the mortality rate was 55% (and 55% of these patients even did not make it to ICU), and the length of ED stay was 6.75 ± 4.4 days, whereas these values were 21.9% (they all died inside ICU) and 6.5 hours (range, 1.4-28.2 hours) in the study of Green and MacIntyre [25]. The data are indicative of the fact that despite having more severe medical conditions, our patients wait for a longer period to be admitted to the ICU. In our study, only 5.56% of the deaths had occurred in less than 24 hours after ED admission (Table 3). There was no direct correlation found between days of emergency admission and mortality, and most of the mortality (50%) had happened between second and fifth day probably because of instability and critical phases of disease. Although in the different mean APACHE III score groups the observed mortality rate was higher than the predicted mortality rate, it followed the correlation between increased APACHE III score and increased mortality rate. Furthermore, there was a linear correlation between increase in predicted mortality and observed mortality rates.
5. Conclusion Emergency department is the entry point to medical care for patients. The patients in ED usually arrive because of the urgent nature of their problem and cannot choose their hospital or their physician. In addition, sometimes, they are taken to hospital against their will by their families or emergency medical services. This should be taken into account even more in patients who need urgent and intensive care because they usually are taken to the nearest referral center and, after initial assessment, they need to be admitted in ICU. The results of our study show that the APACHE III scoring system can also be used in ED the way it is used in ICU to evaluate the quality of care and treatment as well as prognosis of the patients. The huge discrepancy between expected and observed mortality in our study could be accounted for by the shortcomings in equipment and human
Evaluation of the APACHE III resource (personnel) training and the nature of ED as a place to give acute and primary care rather than intensive care. In the hospital where this study was carried out, there is only 1 ED nurse for every 3 to 4 (3.5) beds, which is a small number compared with the standard ratio of 1:1 or 1:2 [26]. Moreover, many of these personnel lack the necessary experience in the provision of intensive care. In some cases, the only intensive care that these patients were provided with was mechanical ventilation, whereas other basic ICU equipments such as cardiac monitoring and pulse oximetry were unavailable. Aside from this, many of the subspecialty services do not visit these patients in ED as regularly as they should, which leads to these patients being forgotten about in the hectic atmosphere of ED. The next step in our studies is to design a study to calculate and compare the APACHE III score on a daily basis in the patients in need of intensive care in ED and follow them up during their hospital stay. By using this method, we hope to be able to evaluate the cause for the changes in the condition of patients and also predict the optimum length of stay for patients in the ED, which may improve their prognosis.
Acknowledgment The research grant given by Shahid Beheshti University of Medical Sciences for the support of this work is highly appreciated.
References [1] Kalb PE, Miller DH. Utilization strategies for intensive care units. JAMA 1989;261(16):2389-95, doi:10.1001/jama.1989.03420160121035. [2] Bongard FS, Sue DY. Current critical care diagnosis and treatment, 2nd ed. McGraw Hill; 2002. p. 10-3. [3] Chang RWS. Individual outcome prediction models for intensive care units. Lancet 1989;2:143-6, doi:10.1016/S0140-6736(89)90193-1. [4] Knaus WA, Zimmerman JE, Wagner DP, et al. APACHE-acute physiology and chronic health evaluation: a physiologically based classification system. Crit Care Emerg Med 1981;9(8):591-7. [5] Junker CD, Zimmerman JE. Severity of illness scoring systems. In: Parrillo JE, Dellinger RP, editors. Critical care medicine: principles of diagnosis and management in the adult, 2nd edSt. Louis, Missouri: Mosby, Inc; 2002. p. 1597-610. [6] Nelson M, Waldrop RD, Jones J, et al. Critical care provided in an urban emergency department. Am J Emerg Med 1998;16(1):56-9. [7] Hatamabadi H, Mohammadi A. Causes of length of stay in a typical overcrowded emergency of a teaching hospital in Tehran Capital city. Pajoohandeh J 2008;13(1):71-5.
1145 [8] Varon J, Fromm RE, Levine RL. Emergency department procedures and length of stay for critically ill medical patients. Ann Emerg Med 1994;23(3):546-9. [9] Hardern R, Taylor A, Shelton R, et al. Developing a rapid diagnosis and treatment centre: estimating impact on hospital resources. Emerg Med J 2004;21(2):165-9, doi:10.1136/emj.2003.012831. [10] Mace SE, Graff L, Mikhail M, et al. A national survey of observation units in the United States. Am J Emerg Med 2003;21(7):529-33, doi: 10.1016/j.ajem.2003.08.012. [11] Bobzien III WF. The observation-holding area: a prospective study. JACEP 1979;8(12):508-12, doi:10.1016/S0361-1124(79)80296-8. [12] Behroozian R, Aghdashi A, Rahimi MH, et al. Assessment of mortality rate and care qualities of ICU department using APACHE III measures. Urmia Med J 2006;17(1):6-12. [13] Wong DT, Crofts ST, Gomez M, et al. Evaluation of predictive ability of APACHE II system and hospital outcome in Canadian intensive care unit patients. Crit Care Med 1995;23(7):1177-83. [14] Gholami F, Khamseh F, Naddaf AR. Predicting the mortality risk of ICU patients in Booali hospital using APACHE III system. Med Sci J 2006;16(4):217-20 Islamic Azad University,Tehran Medical Branch. [15] Knaus WA. APACHE 1978-2001: the development of quality assurance system based on prognosis. Milestones and personal reflections. Archsurgx 2002;137(1):37-41. [16] Sirio CA, Tajimi K, Taenaka N. A cross-cultural comparison of critical care delivery: Japan and the United States. Chest 2002;121(2):539-48, doi:10.1378/chest.121.2.539. [17] Akbari M, Naghavi M, Soori H. Epidemiology of deaths from injuries in the Islamic Republic of Iran. Eastern Medietr Health J 2006;12:50-8. [18] Hatamabadi HR, Vafaee R, Haddadi M, Abdalvand A, Soori H. Necessity of an integrated road traffic injuries surveillance system: a community-based study. Traffic Inj Prev 2011;12(4):358-62, doi:10.1080/15389588.2011.566656. [19] Hatamabadi HR, Abdalvand A, Safari S, Kariman S, Arhami Dolatabadi A, et al. Tetanus Quick Stick as an applicable and cost-effective test in assessment of immunity status. Am J Em Med 2011;29(7):717-20, doi:10.1016/j.ajem.2010.01.046. [20] Nguyen HB, Rivers EP, Havstad S, et al. Critical care in the emergency department: a physiologic assessment and outcome evaluation. Acad Emerg Med 2000;7(12):1354-61, doi:10.1111/j.1553-2712.2000. tb00492.x. [21] Wood KE, Coursin DB, Grouds RM. Critical care outcomes in the United Kingdom, sobering wake-up call or stability of the lamppost? Chest 1999;115(3):614-6, doi:10.1378/chest.115.3.614. [22] Andrulis DP, Kellermann A, Hintz EA, et al. Emergency departments and crowding in United States teaching hospitals. Ann Emerg Med 1991;20(9):980-6. [23] Jeong I, Kim M, Kim J. Predictive accuracy of severity scoring system: a prospective cohort study using APACHE III in a Korean intensive care unit. Int J Nurs Stud 2003;40(3):219-26, doi:10.1016/S00207489(02)00062-7. [24] http://www.amar.org.ir. [25] Green RS, MacIntyre JK. Critical care in the emergency department: an assessment of the length of stay and invasive procedures performed on critically ill ED patients. Scand J Trauma Resusc Emerg Med 2009;17:47, doi:10.1186/1757-7241-17-47. [26] http://www.baccn.org.uk.
www.elsevier.com/locate/ajem
Original Contribution
Evaluation of the Acute Physiology and Chronic Health Evaluation III in predicting the prognosis of patients admitted to Emergency Department, in need of intensive care unit Hamid Reza Hatamabadi MD a, b , Parvin Darbandsar Mazandarani MD a,⁎, Ali Abdalvand MD a , Ali Arhami Dolatabadi MD a , Afshin Amini MD a , Hamid Kariman MD a , Hojjat Derakhshanfar MD a a
Department of Emergency Medicine, Imam Hosain Hospital, Shahid Beheshti University of Medical Sciences, Tehran 1617763141, Iran b Intentional Injury Unit, Safety Promotion and Injury Prevention Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran Received 18 May 2011; revised 4 August 2011; accepted 5 August 2011
Abstract Introduction: Many of critically ill patients receive medical care for prolonged periods in emergency department (ED). This study is the evaluation of efficiency of Acute Physiology and Chronic Health Evaluation (APACHE) III scoring system in predicting mortality rate in these patients. Methods: This study was conducted between 2008 and 2009 in Tehran, Iran. One hundred subjects were enrolled in the study. Cases were chosen from patients in need of intensive care unit (ICU) bed who were kept in the ED. The APACHE III scores and predicted and observed mortality rates were calculated using the information from patients' files, interviews with the patients' families, and performing required physical examinations and laboratory tests. Results: The age of the patients and the ED length of stay were 66.07 (±19.92) years and 5.11 (±3.79) days, respectively. The mean (±SD) of APACHE III score of the patients was 58.89 (±18.24). The predicted mortality rate was calculated to be 32.73%, whereas the observed mortality rate was 55%. The mean (±SD) of APACHE III score of survivors and nonsurvivors was 48.63 (±16.35) and 67.63 (±14.84), respectively (P b .001). Furthermore, the ED length of stay was 3.20 (±1.34) and 6.57 (±4.4) days in survivors vs nonsurvivors, respectively (P b .001). Conclusion: The APACHE III score and ED lengths of stay were higher in this study compared with other studies. This could be ascribed to more critical patients presenting to the study center and also limited ICU bed availability. This study was indicative of applicability of APACHE III scoring system in evaluating the quality of care and prognosis of ED patients in need of ICU. © 2012 Elsevier Inc. All rights reserved.
1. Introduction ⁎ Corresponding author. Tel.: +982173432380; fax: +98 2177557069. E-mail address: [email protected] (P. Darbandsar Mazandarani). 0735-6757/$ – see front matter © 2012 Elsevier Inc. All rights reserved. doi:10.1016/j.ajem.2011.08.005
The increasing number of patients and limitations in treatment facilities has brought up the need for an optimum
1142 allocation system for medical services. This need is even more seriously felt in the case of specialized medical services such as intensive care units (ICU) [1]. Based on the data from the United States published in 1982, 40% of patients admitted to the ICU were not admitted properly. That is, either their condition was so poor that even intensive care did not benefit them and did not reduce their mortality or morbidity or their condition was not critical enough to be admitted to the ICU in the first place [2]. Nowadays, physicians as well as patients require guidelines to follow for admission, care, and discharge from ICU, based on updated scientific research and technology [3]. Knaus et al [4] introduced the “Acute Physiology and Chronic Health Evaluation” (APACHE) system in 1981 to classify disease severity and predict future events in the course of disease. Further studies by the same group led to the development of APACHE III in 1991. In this system, data are gathered from patients, which include 16 different physiologic variables, age, history of chronic diseases, final diagnosis, and place of admission before transfer to the ICU. Manyofthepatientsinneedofintensivecareareadmittedand givencareinemergencydepartment(ED),forextensiveamount of time because of limited bed availability in the ICUs [5-8]. Therefore,technicalsupportandimprovementofEDpersonnel trainingarenecessarytoenhancethequalityofcareforpatientsin need of intensive care before their admission to ICUs. Furthermore, a diagnosis cannot be made during the first visit in many cases. In these cases, patients should be admitted and observedintheEDforawhilebeforeadiagnosiscanbemadeand thepatient betransferred to ICU.Another group ofpatients who are often admitted in the ED are unstable patients who cannot be admittedinthegeneralwardsofthehospital,thus,needtobecared andtreatedinEDwhilewaitingforavacantbedinICU[9,10].The aforementionedissuesledtothedevelopmentofanobservation unit in or adjacent to the EDs [11,12]. Several studies have evaluated the efficiency of the APACHE III system as a tool to evaluatethequalityofcareintheICUs[13-15]. In the ED of Imam Hosain Hospital in Tehran, Iran, emergency medicine specialists and residents look after the patients who are in need of ICU beds admitted to the ED. Based on current standards, the ratio of intensive care beds to regular beds should be 10% [16]. In Iran, this number is roughly 3%, and in Imam Hosain Hospital, 6% of the beds are ICU beds. Considering the current number of road accident casualties and heart disease victims (which are 2 main constituents of patients in need of ICU care in Iran [17]), there is a serious shortcoming in number of ICU beds. Unfortunately, Iran has the first place in the number of traffic accidents and annual death from road accidents (30 in 100 000 cases) [17-19]; thus, the need for increasing intensive care beds of the ED for observation is inevitable. The primary aim of the present study is to evaluate the efficiency of APACHE III system in predicting patient mortality in the ED. The second aim is to evaluate the quality of care that patients received in the ED by comparing predicted mortality rate with observed mortality rate in these patients.
H.R. Hatamabadi et al.
2. Materials and methods This cross-sectional, analytic study was conducted between March 2008 and March 2009 in the ED of Imam Hosain hospital, Tehran, Iran. This hospital is a tertiary center, which is a teaching hospital with 36 000 annual patient admissions and 450 beds, 21 of which are ICU beds and 30 are ED beds. The study group was patients who were diagnosed with an unstable condition in the ED on admission and in need of ICU bed based on the primary survey, clinical evaluation, and laboratory studies. The patients were followed up until they were either transferred to ICU or died. Inclusion criteria were patients who were visited in the first 6 hours of their admission by an ICU fellow and were candidates for admission to ICU but had to be cared for in the ED because of the lack of free beds in ICU. Exclusion criteria were being younger than 15 years, death within 4 hours of admission, and a lack of definite diagnosis before death. The number of subjects registered was 100, and the sampling was a nonprobability convenience method. This study was approved by the ethics committee of the participating hospital research center. The study variables were composed of (1) demographic data of the patients; (2) primary diagnosis; (3) comorbid medical problem; and (4) vital signs and physiologic indices in the first 24 hours of admission including heart rate per minute, respiratory rate per minute, body temperature (degree Celsius), mean arterial pressure (millimeters of mercury), arterial oxygen pressure (PaO2), or alveolar-arterial oxygen tension difference [PO(A-a)], blood hematocrit percentage, white blood cell count, urine output (milliliters per day), creatinine, blood sodium, bilirubin, albumin, glucose, blood nitrogen urea, and acid-base imbalance (pH and PCO2); (5) APACHE III score; (6) the length of hospital stay in the ED; (7) the number of observed deaths; and (8) the percentage of predicted mortality. In the case of repeated measurement of physiologic indices in the first 24 hours, the worst value was taken into account and recorded. At the same time, the indices, which were not measured, were scored zero. The data gathering was done through APACHE III questionnaire forms using the information in the patient's charts, interviewing the visitors, physical examination, and laboratory tests. The forms were completed either near to the end of the 24th hour of admission in the ED or latter hours of admission when the patient was transferred to the ICU in less than 24 hours. The data were analyzed using the APACHE III-J software and APACHE III score, and first-day mortality prediction (in percentage) was calculated. This software was updated in 1996 by studying 37 000 patients, and the final version is available at www.apache-web.com. SPSS version 11.5 (Chicago, IL) was used to analyze other data including demographic data, diagnosis, length of hospital stay, observed mortality, and its comparison to predicted mortality. Clinical indices were calculated and reported as mean ± SD,
Evaluation of the APACHE III Table 1
1143
Demographic characteristics of patients
Number enrolled in study
N = 100
Age (y), mean ± SD Sex Male Female ED length of stay (d)
66.07 ± 19.92
Nonsurvivors Age (y), mean ± SD Sex Male Female ED length of stay (d)
n = 55 74.93 ± 13.19
Survivors Age (y), mean ± SD Sex Male Female ED length of stay (d)
n = 45 55.24 ± 21.47
56 (56%) 44 (44%) 5.11 ± 3.79
28 (51%) 27 (49%) 6.57 ± 4.40
28 (62%) 17 (38%) 3.20 ± 1.34
and the Student t test was used for statistical analysis, with the α set to .05.
3. Results One hundred patients were eligible to enter this study, of which 55 died during their ED admission. The demographic data and length of hospital stay in both survived and deceased groups are shown in Table 1. Mean APACHE III score for the first day in all patients was 58.89 ± 18.24, and the predicted mortality was 32.73%. The mean APACHE III score, length of hospital stay, and age were significantly higher in the deceased group vs surviving group (P b .001) (Table 2). Among the patients in need of ICU who were admitted in the ED, the group with APACHE III score of 50 to 70 had the greatest prevalence. Fig. 1 shows the relation between APACHE III score and hospital mortality rate in each group. Comparison between predicted and observed mortality based on the APACHE III score indicates significant difference between these 2 in favor of the latter (Fig. 2).
Fig. 1 Relationship between APACHE III score and risk of hospital death.
This relation still follows the correlation between APACHE III score and mortality. Fig. 3 shows a linear correlation between predicted and observed mortality. Fig. 4 and Table 3 show the patient mortality based on the length of stay.
4. Discussion Since the introduction of APACHE III evaluation system by Knaus et al in 1991, its efficiency as a tool to evaluate expected mortality and quality of care in ICU has been studied several times in Iran and other places around the world [20]. The ever increasing number of patients in unstable condition in need of critical care has led to better provision of EDs with necessary equipments [21]. This, in turn, has raised the need for evaluation of the quality of care and its effect on the prognosis of patients. It has also necessitated the provision of further equipment and personnel training to EDs. The APACHE III system can be of great help in these kinds of evaluations, but its efficiency should first be confirmed.
Table 2 Mean APACHE III score, ED length of stay, and age in survivors vs nonsurvivors
APACHE III score, mean ± SD ED length of stay (d) Age (y), mean ± SD
Nonsurvivors
Survivors
P
67.63 ± 14.84
48.63 ± 16.35
b.001
6.57 ± 4.40 74.93 ± 13.19
3.20 ± 1.34 55.24 ± 21.47
b.001 b.001
Fig. 2 Expected and observed mortality rates based on APACHE III score.
1144
H.R. Hatamabadi et al. Table 3
Patients mortality based on ED length of stay
ED length of stay (d) ≤1 2-5 6-9 10-13 14-17 18-21 Total
Fig. 3
Risk stratification of mortality rate by APACHE III score.
In our study of 100 patients in the Imam Hosain hospital, the mean APACHE III score was 58.89 ± 18.24, whereas in 2 studies in Bou Ali Hospital (Tehran, Iran) and Imam Khomeini Hospital (Urmia, Iran), this score was shown to be 60.6 and 35.48, respectively [12,14]. This score has also been calculated and reported in other studies from United States (APACHE III score, 50), Japan (APACHE III score, 52.7), England (APACHE III score, 56.8), and South Korea (APACHE III score, 48.60) [21-23]. By comparing the scores, it could be implied that the patients in our study were generally having more severe problems. This could be due to the abundant number of patients who were referred to Imam Hosain hospital ED accompanied by the limited number of ICU beds available in the hospital. This combination has probably left the caregivers no other choice than to candidate patients for ICU admission in poorer conditions and with higher APACHE III scores. Furthermore, the patients in our study were older when means of age were compared with the aforementioned studies [16,24]. To the best of our knowledge, this study is the first of its kind in Iran. However, when we compared our results with a study from the United States that had used APACHE II scoring system [22], the differences were astonishing. The
Fig. 4
Patients mortality based on ED length of stay.
Nonsurvivors n
%
3 27 9 11 2 2 54
5.56 50 16.67 20.27 3.7 3.7 100
mean of hospital stay for patients in ED before being transferred to the ICU in our study was 5.11 ± 3.79 days, whereas it was 5.9 ± 2.7 hours in the aforementioned study, which is a large difference. In our study, the mortality rate was 55% (and 55% of these patients even did not make it to ICU), and the length of ED stay was 6.75 ± 4.4 days, whereas these values were 21.9% (they all died inside ICU) and 6.5 hours (range, 1.4-28.2 hours) in the study of Green and MacIntyre [25]. The data are indicative of the fact that despite having more severe medical conditions, our patients wait for a longer period to be admitted to the ICU. In our study, only 5.56% of the deaths had occurred in less than 24 hours after ED admission (Table 3). There was no direct correlation found between days of emergency admission and mortality, and most of the mortality (50%) had happened between second and fifth day probably because of instability and critical phases of disease. Although in the different mean APACHE III score groups the observed mortality rate was higher than the predicted mortality rate, it followed the correlation between increased APACHE III score and increased mortality rate. Furthermore, there was a linear correlation between increase in predicted mortality and observed mortality rates.
5. Conclusion Emergency department is the entry point to medical care for patients. The patients in ED usually arrive because of the urgent nature of their problem and cannot choose their hospital or their physician. In addition, sometimes, they are taken to hospital against their will by their families or emergency medical services. This should be taken into account even more in patients who need urgent and intensive care because they usually are taken to the nearest referral center and, after initial assessment, they need to be admitted in ICU. The results of our study show that the APACHE III scoring system can also be used in ED the way it is used in ICU to evaluate the quality of care and treatment as well as prognosis of the patients. The huge discrepancy between expected and observed mortality in our study could be accounted for by the shortcomings in equipment and human
Evaluation of the APACHE III resource (personnel) training and the nature of ED as a place to give acute and primary care rather than intensive care. In the hospital where this study was carried out, there is only 1 ED nurse for every 3 to 4 (3.5) beds, which is a small number compared with the standard ratio of 1:1 or 1:2 [26]. Moreover, many of these personnel lack the necessary experience in the provision of intensive care. In some cases, the only intensive care that these patients were provided with was mechanical ventilation, whereas other basic ICU equipments such as cardiac monitoring and pulse oximetry were unavailable. Aside from this, many of the subspecialty services do not visit these patients in ED as regularly as they should, which leads to these patients being forgotten about in the hectic atmosphere of ED. The next step in our studies is to design a study to calculate and compare the APACHE III score on a daily basis in the patients in need of intensive care in ED and follow them up during their hospital stay. By using this method, we hope to be able to evaluate the cause for the changes in the condition of patients and also predict the optimum length of stay for patients in the ED, which may improve their prognosis.
Acknowledgment The research grant given by Shahid Beheshti University of Medical Sciences for the support of this work is highly appreciated.
References [1] Kalb PE, Miller DH. Utilization strategies for intensive care units. JAMA 1989;261(16):2389-95, doi:10.1001/jama.1989.03420160121035. [2] Bongard FS, Sue DY. Current critical care diagnosis and treatment, 2nd ed. McGraw Hill; 2002. p. 10-3. [3] Chang RWS. Individual outcome prediction models for intensive care units. Lancet 1989;2:143-6, doi:10.1016/S0140-6736(89)90193-1. [4] Knaus WA, Zimmerman JE, Wagner DP, et al. APACHE-acute physiology and chronic health evaluation: a physiologically based classification system. Crit Care Emerg Med 1981;9(8):591-7. [5] Junker CD, Zimmerman JE. Severity of illness scoring systems. In: Parrillo JE, Dellinger RP, editors. Critical care medicine: principles of diagnosis and management in the adult, 2nd edSt. Louis, Missouri: Mosby, Inc; 2002. p. 1597-610. [6] Nelson M, Waldrop RD, Jones J, et al. Critical care provided in an urban emergency department. Am J Emerg Med 1998;16(1):56-9. [7] Hatamabadi H, Mohammadi A. Causes of length of stay in a typical overcrowded emergency of a teaching hospital in Tehran Capital city. Pajoohandeh J 2008;13(1):71-5.
1145 [8] Varon J, Fromm RE, Levine RL. Emergency department procedures and length of stay for critically ill medical patients. Ann Emerg Med 1994;23(3):546-9. [9] Hardern R, Taylor A, Shelton R, et al. Developing a rapid diagnosis and treatment centre: estimating impact on hospital resources. Emerg Med J 2004;21(2):165-9, doi:10.1136/emj.2003.012831. [10] Mace SE, Graff L, Mikhail M, et al. A national survey of observation units in the United States. Am J Emerg Med 2003;21(7):529-33, doi: 10.1016/j.ajem.2003.08.012. [11] Bobzien III WF. The observation-holding area: a prospective study. JACEP 1979;8(12):508-12, doi:10.1016/S0361-1124(79)80296-8. [12] Behroozian R, Aghdashi A, Rahimi MH, et al. Assessment of mortality rate and care qualities of ICU department using APACHE III measures. Urmia Med J 2006;17(1):6-12. [13] Wong DT, Crofts ST, Gomez M, et al. Evaluation of predictive ability of APACHE II system and hospital outcome in Canadian intensive care unit patients. Crit Care Med 1995;23(7):1177-83. [14] Gholami F, Khamseh F, Naddaf AR. Predicting the mortality risk of ICU patients in Booali hospital using APACHE III system. Med Sci J 2006;16(4):217-20 Islamic Azad University,Tehran Medical Branch. [15] Knaus WA. APACHE 1978-2001: the development of quality assurance system based on prognosis. Milestones and personal reflections. Archsurgx 2002;137(1):37-41. [16] Sirio CA, Tajimi K, Taenaka N. A cross-cultural comparison of critical care delivery: Japan and the United States. Chest 2002;121(2):539-48, doi:10.1378/chest.121.2.539. [17] Akbari M, Naghavi M, Soori H. Epidemiology of deaths from injuries in the Islamic Republic of Iran. Eastern Medietr Health J 2006;12:50-8. [18] Hatamabadi HR, Vafaee R, Haddadi M, Abdalvand A, Soori H. Necessity of an integrated road traffic injuries surveillance system: a community-based study. Traffic Inj Prev 2011;12(4):358-62, doi:10.1080/15389588.2011.566656. [19] Hatamabadi HR, Abdalvand A, Safari S, Kariman S, Arhami Dolatabadi A, et al. Tetanus Quick Stick as an applicable and cost-effective test in assessment of immunity status. Am J Em Med 2011;29(7):717-20, doi:10.1016/j.ajem.2010.01.046. [20] Nguyen HB, Rivers EP, Havstad S, et al. Critical care in the emergency department: a physiologic assessment and outcome evaluation. Acad Emerg Med 2000;7(12):1354-61, doi:10.1111/j.1553-2712.2000. tb00492.x. [21] Wood KE, Coursin DB, Grouds RM. Critical care outcomes in the United Kingdom, sobering wake-up call or stability of the lamppost? Chest 1999;115(3):614-6, doi:10.1378/chest.115.3.614. [22] Andrulis DP, Kellermann A, Hintz EA, et al. Emergency departments and crowding in United States teaching hospitals. Ann Emerg Med 1991;20(9):980-6. [23] Jeong I, Kim M, Kim J. Predictive accuracy of severity scoring system: a prospective cohort study using APACHE III in a Korean intensive care unit. Int J Nurs Stud 2003;40(3):219-26, doi:10.1016/S00207489(02)00062-7. [24] http://www.amar.org.ir. [25] Green RS, MacIntyre JK. Critical care in the emergency department: an assessment of the length of stay and invasive procedures performed on critically ill ED patients. Scand J Trauma Resusc Emerg Med 2009;17:47, doi:10.1186/1757-7241-17-47. [26] http://www.baccn.org.uk.