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Comparative analysis of emergency department treatment of patients with chest pain
o~RIGINAL CONTRIBUTION
Comparative Analysis of Emergency Department Treatment of Patients with Chest Pain Bernard Slosberg, MD, MPH* Nancy link, BAt Geoffrey Gibson, PhDt
A vital f u n c t i o n o f t h e e m e r g e n c y p h y s i c i a n is s e p a r a t i n g p a t i e n t s w i t h chest p a i n w h o r e q u i r e i n t e n s i v e i m m e d i a t e t r e a t m e n t f r o m t h o s e w h o require m i n i m a l c a r e . T h e c a r e o f 701 p a t i e n t s p r e s e n t i n g w i t h c h e s t pain in t w o B a l t i m o r e h o s p i t a l s w a s e v a l u a t e d u s i n g m e d i c a l r e c o r d data a n d • f o l l o w - u p q u e s t i o n n a i r e s to d i s c h a r g e d p a t i e n t s . T w e n t y p e r cent w e r e a d m i t t e d . T h e r e w a s a s i g n i f i c a n t d i f f e r e n c e b e t w e e n t h e t w o hospitals in a d m i s s i o n r a t e s . T h i r t y - f i v e p e r c e n t o f t h e d i s c h a r g e d patients felt n o b e t t e r t w o w e e k s a f t e r e m e r g e n c y d e p a r t m e n t d i s c h a r g e . Plans for f u r t h e r r e s e a r c h i n c l u d e a s t u d y to c l a r i f y t h e d i f f e r e n c e in a d m i s s i o n r a t e s a n d the c h a r a c t e r i s t i c s o f i n d i v i d u a l s w h o r e m a i n e d s y m p t o m a t i c at t w o w e e k s .
rate for p a t i e n t s with myocardial inf a r c t i o n f o l l o w i n g a d m i s s i o n to a coronary care u n i t (CCU). Norris et al s e v a l u a t e d 530 patients following C C U d i s c h a r g e a n d f o u n d a 33% t h r e e - y e a r m o r t a l i t y rate. B a l a n c i n g these profound risks is the fact t h a t CCU care m a y cost as much as $300 to $400 per day and may have serious psychological and medical complications.
SIosberg B, Fink N, Gibson G: Comparative analysis of emergency department treatment of patients with chest pain. JACEP 6:445-448, October, 1977. chest pain, emergency care, analysis, comparison.
Emergency department personnel know of i n d i v i d u a l s discharged only to r e t u r n s h o r t l y w i t h a n e v i d e n t myocardial infarction or DOA. CCU staff are g e n e r a l l y concerned t h a t too m a n y p a t i e n t s are b e i n g " u n n e c e s s a r i l y " a d m i t t e d for m o n i t o r i n g as ~rule out myocardial infarction (MI)" or '~chest pain of u n k n o w n etiology." This l a t t e r circumstance m a y hamper C C U e f f e c t i v e n e s s , d e p e n d i n g on occupancy rate and the severity i n the census.
INTRODUCTION The broad range of etiologies and severity i n p a t i e n t s with chest pain, from i m m e d i a t e l i f e - t h r e a t e n i n g to the clinically m u n d a n e , creates a difficult clinical problem for emergency physicians. 1 F u r t h e r m o r e , the clinical signs a n d symptoms as well as the basic laboratory assessment are noted for l a c k of s e n s i t i v i t y a n d
From the Division of Emergency Medicine,* Baltimore City Hospital, and the Health Services Research and Development Center, Division of Emergency Medicine,*t The Johns Hopkins Medical Institutions, Baltimore, Maryland. Supported by grant HS01310 from the •National Center for Health Services ReSearch, DHEW, to the Johns Hopkins Health Services Research and Develop-
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specificity. 2 The p a t i e n t with atypical moderate pain and a n o r m a l electrocardiogram (EKG) and chest x-ray film m a y be h a v i n g u n s t a b l e a n g i n a and be at risk of sudden death. On the other hand, a p a t i e n t with typical "ischemic" p a i n and nonspecific E K G a b n o r m a l i t i e s m a y merely have a "chest-wall syndrome. ''3,4 Killip et aP found a 25% m o r t a l i t y
ment Center, Johns Hopkins University. Presented at the annual University Association for Emergency Medicine meeting in Kansas City, Missouri, May, 1977. Address for r e p r i n t s ~ e r n a r d Slosberg, MD, MPH, Division 6~ Emergency Med.icine, Baltimore City Hospital, 4940 Eastern Avenue, Baltimore, Maryland 21224.
A d m i t t i n g enough versus not adm i t t i n g too m a n y is a fine line. Schor et al 7 e v a l u a t e d the e m e r g e n c y dep a r t m e n t t r e a t m e n t in Israel of 1,578 cases referred for possible MI. T e n per cent of those with a n MI were ina d v e r t e n t l y discharged from the ED a n d 28% of a d m i s s i o n s were subs e q u e n t l y judged unnecessary. Since in this c o u n t r y m o s t e m e r g e n c y dep a r t m e n t p a t i e n t s are self-referred, it would be difficult to e x t r a p o l a t e
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t h e s e f i n d i n g s or d u p l i c a t e such a sample. The purpose of the p r e s e n t s t u d y is to develop a methodology to m o n i t o r overall e m e r g e n c y d e p a r t m e n t evalu a t i o n of p a t i e n t s w i t h chest pain. S i n c e a b s o l u t e m e a s u r e s of effectiveness are not available, two e m e r g e n c y d e p a r t m e n t s were chosen for a c o m p a r a t i v e analysis. The init i a l objectives were to c o m p a r e the p a t i e n t populations a n d the results of t r e a t m e n t of c h e s t pain, a d m i s s i o n rates, a n d s y m p t o m a t i c r e l i e f in discharged patients.
METHODS Seven h u n d r e d a n d one consecutive p a t i e n t s w i t h the c o m p l a i n t of chest p a i n p r e s e n t i n g at the Baltim o r e C i t y H o s p i t a l (BCH) or t h e J o h n s H o p k i n s H o s p i t a l (JHH) were selected for t h e study. The study cove r e d t h e t i m e p e r i o d O c t o b e r 23, 1976 to N o v e m b e r 23, 1976. A pat i e n t was included if chest pain was a single c o m p l a i n t or p a r t of a m u l t i p l e c o m p l a i n t received by an e m e r g e n c y medical t e c h n i c i a n (EMT), a nurse or emergency department registrar. In a d d i t i o n to basic c h a r a c t e r i s t i c s (Figure), the h o s p i t a l s differ organi z a t i o n a l l y for t h e u n s c h e d u l e d pat i e n t w i t h a p r e s u m e d m i n o r problem. A t J H H , t h e r e is a p r i m a r y care c e n t e r (PCC) in an a d j a c e n t b u i l d i n g t h a t functions 9 am to 5 pro, Monday t h r o u g h Friday. P a t i e n t s m a y "walk in" directly to the PCC for care and also m a y be referred t h e r e from the e m e r g e n c y d e p a r t m e n t . At BCH all u n s c h e d u l e d p a t i e n t s are seen in the e m e r g e n c y d e p a r t m e n t . In order to create c o m p a r a b l e samples, the J H H s a m p l e i n c l u d e s p a t i e n t s from t h e PCC and the e m e r g e n c y d e p a r t m e n t . The e m e r g e n c y d e p a r t m e n t records of all p a t i e n t s were a b s t r a c t e d to obt a i n d a t a on socioeconomic, demog r a p h i c a n d c l i n i c a l v a r i a b l e s . The signs, s y m p t o m s , a n d r e s u l t s of all clinical tests were recorded. For t h o s e p a t i e n t s d i s c h a r g e d home, a telephone or p e r s o n a l i n t e r v i e w was c o n d u c t e d two w e e k s a f t e r t h e e m e r g e n c y d e p a r t m e n t visit. This interview a s c e r t a i n e d the need for unscheduled m e d i c a l care, c h a n g e s in s y m p t o m levels a n d disability, ie, int e r f e r e n c e w i t h the p a t i e n t ' s u s u a l a c t i v i t i e s . F o r t h e p a t i e n t s hos-
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HOSPITALS Baltimore City Hospital 1) C i t y - o p e r a t e d ; affiliated
Johns Hopkins Hospital
university
1) University hospital 2) 1200 beds
2) 600 beds
3) L o c a t i o n - - i n n e r city indigent area
3) L o c a t i o n - - l o w e r middle c l a s s - industrial
4) ED use - - 92,000 patients/ year
4) ED use - - 46,800 patients/ year
5) ED staffing - - house staff with teaching attendings
5) ED staffing - - house staff with teaching attendings
F i g u r e . Study hospital characteristics c a n t l y different between the hospitals (Table 1).
Table 1 INCIDENCE OF CHEST PAIN No.
Percent
BCH JHH
236 465
6.4 6.6
TOTAL:
701
6.5
Patient Characteristics
pitalized at t h e visit, an a b s t r a c t of the i n p a t i e n t record was o b t a i n e d inc l u d i n g the r e s u l t s of clinical e x a m i nations, p r i n c i p a l l y the E K G and enz y m e s t u d i e s . T h e l e n g t h of hosp i t a l i z a t i o n a n d all d i s c h a r g e diagnoses were recorded. Statistical differences between ratios were tested u s i n g chi s q u a r e analysis. Patient symptoms were coded u s i n g t h e N a t i o n a l A m b u l a t o r y Care S u r v e y Classification s a n d diagnostic i n f o r m a t i o n was coded by the H-ICDA.
RESULTS The Sample and Incidence of Chest Pain The d i s t r i b u t i o n of the sample and the incidence of the c o m p l a i n t show t h a t the incidence was not signifi-
Age. By chi s q u a r e analysis, the age d i s t r i b u t i o n s a r e significantly d i f f e r e n t , i n d i c a t i n g t h e J H H pa. t i e n t s are y o u n g e r w i t h a prominent proportion u n d e r age 30 (Table 2). Race and Sex. Sixty-one per cent of t h e p a t i e n t s w e r e b l a c k a n d 56~ were women. These r a t i o s do not differ s i g n i f i c a n t l y from a l l patients u s i n g t h e e m e r g e n c y department.S T h e r e w e r e v e r y s i g n i f i c a n t differences in the race and sex proportions b e t w e e n h o s p i t a l s (Table 3). Clinical Characteristics. Three m e a s u r e s were used to assess severi t y in t h e two cohorts: 1) need for a m b u l a n c e service; 2) a positive history ~or cardiac disease, and 3) the presence of h e a r t disease as an exp l a n a t i o n for t h e chest pain. Ambul a n c e t r a n s p o r t w a s r e q u e s t e d by 17% of t h e o v e r a l l s a m p l e with no noted difference b e t w e e n hospitals. T w e n t y - t h r e e per cent were n o t e d to have a prior h i s t o r y of h e a r t disease a n d in 18% c a r d i a c d i s e a s e was t h o u g h t to be t h e r e a s o n for chest p a i n at t h e p r e s e n t visit. The propor-
Table 2 AGE DISTRIBUTION OF STUDY S A M P L E S JHH
BCH AGE
No.
%
No,
%
18-30 31-40 41-50 51-6O 61-70 70
47 39 42 53 28 26
20 16 " 18 23 12 11
142 82 72 86 42 4O
31 18 16 18 9 8
236
100
465
100
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Table 3 RACE AND SEX DISTRIBUTION (%) Race BCH JHH Sex BCH JHH
Table 4 MEASURES OF SEVERITY (%)
Black
White
24 80
76 20
Female
Male
47 60
53 40
tiqn with a h i s t o r y of cardiac disease or an acute cardiac diagnosis was not different b e t w e e n the two h o s p i t a l s (Table 4).
Admission rates. The o v e r a l l admission r a t e for t h e c o h o r t of patients was 20%, which is considerably higher t h a n the a d m i s s i o n r a t e for e m e r g e n c y d e p a r t m e n t p a t i e n t s 2 The BCH r a t e was 25.8% and J H H was 17.2%, a s t a t i s t i c a l l y significant difference.
Follow-up of discharged patients. A questionnaire response r a t e of 82% was achieved on the sample of chest pain p a t i e n t s d i s c h a r g e d from t h e emergency d e p a r t m e n t . One d e a t h was identified. Thirty-five percent of the i n d i v i d u a l s c o n t a c t e d h a d t h e same or more p a i n t h a n at t h e i r initial visit. These r e s u l t s in discharged patients were n o t s i g n i f i c a n t l y different b e t w e e n t h e two hospitals. DISCUSSION During the course of p u r s u i n g the study's m a j o r o b j e c t i v e - - t h e development of a nonintervening method to e v a l u a t e e m e r g e n c y department p e r f o r m a n c e c h a r a c t e r i s tics' of p a t i e n t s w i t h chest p a i n - - ins t i t u t i o n a l d i f f e r e n c e s were d e t e r mined. T h e i n c i d e n c e of t h e complaint was the s a m e a t both hospitals and it is u n c h a n g e d from a s i m i l a r study conducted at J H H in 1974.1° The age, sex, a n d r a c i a l c h a r a c t e r i s tics were not s i g n i f i c a n t l y different from o t h e r s a m p l e s of e m e r g e n c y dep a r t m e n t u s e r s of t h e s a m e e m e r gency d e p a r t m e n t s 2 H o w e v e r , t h e BCH s a m p l e is more affluent, older, tends to h a v e a h i g h e r p r o p o r t i o n of males, a n d h a s a v e r y d i f f e r e n t racial c o m p o s i t i o n f r o m t h e J H H I Sample. Despite these socioeconomic differences, the m e a s u r e s of medical
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Ambulance use Heart disease Cardiac diagnosis at visit
significance used: 1) the need for ambulance t r a n s p o r t , 2) the proportion of t h e s a m p l e w i t h k n o w n c a r d i a c disease, a n d 3) t h e proportion of those w i t h c a r d i a c d i a g n o s i s a t the visit, showed no difference between the two hospitals. B a l t i m o r e h a s a sophisticated public e m e r g e n c y a m b u l a n c e s y s t e m w i t h l i b e r a l access. The s e r v i c e is free a n d m o s t all p a t i e n t s who request t h e service are t r a n s p o r t e d to t h e n e a r e s t hospital. 11 The m e a s u r e of a m b u l a n c e use is therefore more closely r e l a t e d to c o n s u m e r r a t h e r than professional perception of u r g e n c y or s e v e r i t y . Socioeconomic, educational, and cultural factors l i k e l y p l a y a m o r e s i g n i f i c a n t role t h a n a c t u a l m e d i c a l severity. T h i s s t u d y c o n f i r m s the c l i n i c a l n o t i o n t h a t a s m a l l p r o p o r t i o n of chest pain p a t i e n t s have an u r g e n t or e m e r g e n c y problem, a history of card i a c d i s e a s e , or a n a c u t e c a r d i a c diagnosis. T h e c h a r a c t e r i s t i c s of t h e c h e s t p a i n cohorts at t h e .two hospitals are t h o u g h t to be r e p r e s e n t a t i v e of the p o p u l a t i o n s l i v i n g n e a r each hospital. In B a l t i m o r e , this is reinforced b y the n e a r e s t h o s p i t a l rule of the public a m b u l a n c e system. The o v e r a l l a d m i s s i o n r a t e s for the chest p a i n p a t i e n t s are h i g h e r t h a n for all e m e r g e n c y d e p a r t m e n t u s e r s 2 The crude r a t e differs s i g n i f i c a n t l y b e t w e e n t h e two h o s p i t a l s , d e s p i t e s i m i l a r i t i e s of s e v e r a l m e a s u r e s of s e v e r i t y . Two a d d i t i o n a l p h a s e s of t h i s s t u d y will explore the m e a n i n g of this difference a n d put it into a b r o a d e r perspective. First, a m u l t i p l e r e g r e s s i o n model is being developed to a l l o t t h e effects of d e m o g r a p h i c a n d medical v a r i a b l e s on the admission r a t e s and s e c o ~ y , the f a t a l i t y r a t e s in the m o n t h following emergency department discharge will be a s c e r t a i n e d from a n y d e a t h r e c -
BCH
JHH
TOTAL
20 20.8
15.7 23.6
17 23
21
17
18
ords for t h e cohort. A p l a n n e d parallel quality of care study using this data base will estimate and compare the proportion j u d g e d to be " i n a p p r o p r i a t e l y " d i s c h a r g e d from the e m e r g e n c y d e p a r t m e n t a n d those " u n n e c e s s a r i l y " admitted. The s t u d y will use "blind" p h y s i c i a n j u d g e s of case a b s t r a c t s a n d actual E K G s . E x p e r i e n c e w i t h the home quest i o n n a i r e is p r o m i s i n g ; a 82% response r a t e was achieved. I n i t i a l l y , we hoped t h a t the d a t a could help est i m a t e t h e p r o p o r t i o n of i n a p p r o priate discharges but this was not r e a l i z e d s i n c e o n l y one d e a t h w a s identified. It is very likely t h a t the adverse results would aggregate a m o n g t h e n o n r e s p o n d e n t s . There= fore, in t h e future, d e a t h records and i m p l i c i t p h y s i c i a n j u d g e m e n t s will be used for such e s t i m a t e s . The major outcome r e p o r t e d from the questionn a i r e to date, ie, s y m p t o m r e l i e f at two weeks, is sobering but the medical c h a r a c t e r i s t i c s of these individuals will h a v e to be f u r t h e r analyzed. Due to the p o t e n t i a l of i m p r o v i n g p e r f o r m a n c e when these studies are c o m p l e t e , s e v e r a l i n t e r v e n t i o n s in o u r e m e r g e n c y d e p a r t m e n t practice a r e b e i n g considered. A m o n g t h e m are a systematic educational report of s t u d y r e s u l t s and a new a p p r o a c h to care based on e l i c i t i n g two indep e n d e n t m e d i c a l histories on p a t i e n t s w i t h c h e s t pain. T h i s l a t t e r w o u l d t e n d to i m p r o v e the v a l i d i t y of the subjective clinical data, often the m a j o r aspect of the d a t a base used for the admission decision. Also, the l i k e l i h o o d of a n i n a p p r o p r i a t e disc h a r g e could be further decreased if t h e two i n d e p e n d e n t a s s e s s m e n t s were judged conservatively. Furt h e r m o r e , a periodic review u s i n g this m e t h o d o l o g y m a y be w o r t h w h i l e but for efficiency it should be l i m i t e d to the higher risk chest pain group r a t h e r t h a n the e n t i r e u n i v e r s e of such p a t i e n t s . 447/29
REFERENCES 1. Lichstein E, Seckler S: Evaluation of acute chest pain. Med Clin North A m 57:1481-1490, 1973. 2. Hurst JW: Symptoms Due to Heart Disease, in The Heart, ed 3. New York, McGraw-Hill, 1974, p 140.
5. Killip T, Kimball JT: A survey of the coronary unit. Concepts and results. Prog Cardiovasc Dis 11:45, 1968. 6. Norris RM, Caughey D, Mercer C, et al: Coronary prognostic index for predicting survival aider recovery from acute myocardial infarction. Lancet 2:485, 1970.
3. Braunwald E, Harrison TR: Principles of Internal Medicine, ed 8. New York, McGraw-Hill, 1977, pp 28-33.
7. Schor position from an 941-943,
4. Conti CR, Griffith L, Ross R: Thoracic pain and angina pectoris, in Principles and Practice of Medicine. New York, Apple-Century Crofts, 1976, pp 325-340.
8. The N a t i o n a l A m b u l a t o r y Medical Care Survey: Symptom Classification. DHEW Publication 74-1337, Rockville, Maryland, July, 1976.
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S, Behar S, Modan B, et al: Disof presumed coronary patients e m e r g e n c y room. J A M A 236: 1976.
9. Perspective study of patients presenting with chest pain at the Johns Hopkins Hos. pital and Baltimore City Hospital, October 23 - November 23, 1976. EMS Research Program Projects, Health Services Re. search and Development Center, Johns Hopkins University, Baltimore. 10. Twenty most frequent complaints, ar. ranged by frequency as single complaints. EMS Research Program Projects, Health S e r v i c e s R e s e a r c h a n d Development Center, Johns Hopkins University, BaI. timore, October, 1974. 11. Emergency Ambulance Service. Baltimore City Fire Department, Baltimore, 1965.
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Comparative Analysis of Emergency Department Treatment of Patients with Chest Pain Bernard Slosberg, MD, MPH* Nancy link, BAt Geoffrey Gibson, PhDt
A vital f u n c t i o n o f t h e e m e r g e n c y p h y s i c i a n is s e p a r a t i n g p a t i e n t s w i t h chest p a i n w h o r e q u i r e i n t e n s i v e i m m e d i a t e t r e a t m e n t f r o m t h o s e w h o require m i n i m a l c a r e . T h e c a r e o f 701 p a t i e n t s p r e s e n t i n g w i t h c h e s t pain in t w o B a l t i m o r e h o s p i t a l s w a s e v a l u a t e d u s i n g m e d i c a l r e c o r d data a n d • f o l l o w - u p q u e s t i o n n a i r e s to d i s c h a r g e d p a t i e n t s . T w e n t y p e r cent w e r e a d m i t t e d . T h e r e w a s a s i g n i f i c a n t d i f f e r e n c e b e t w e e n t h e t w o hospitals in a d m i s s i o n r a t e s . T h i r t y - f i v e p e r c e n t o f t h e d i s c h a r g e d patients felt n o b e t t e r t w o w e e k s a f t e r e m e r g e n c y d e p a r t m e n t d i s c h a r g e . Plans for f u r t h e r r e s e a r c h i n c l u d e a s t u d y to c l a r i f y t h e d i f f e r e n c e in a d m i s s i o n r a t e s a n d the c h a r a c t e r i s t i c s o f i n d i v i d u a l s w h o r e m a i n e d s y m p t o m a t i c at t w o w e e k s .
rate for p a t i e n t s with myocardial inf a r c t i o n f o l l o w i n g a d m i s s i o n to a coronary care u n i t (CCU). Norris et al s e v a l u a t e d 530 patients following C C U d i s c h a r g e a n d f o u n d a 33% t h r e e - y e a r m o r t a l i t y rate. B a l a n c i n g these profound risks is the fact t h a t CCU care m a y cost as much as $300 to $400 per day and may have serious psychological and medical complications.
SIosberg B, Fink N, Gibson G: Comparative analysis of emergency department treatment of patients with chest pain. JACEP 6:445-448, October, 1977. chest pain, emergency care, analysis, comparison.
Emergency department personnel know of i n d i v i d u a l s discharged only to r e t u r n s h o r t l y w i t h a n e v i d e n t myocardial infarction or DOA. CCU staff are g e n e r a l l y concerned t h a t too m a n y p a t i e n t s are b e i n g " u n n e c e s s a r i l y " a d m i t t e d for m o n i t o r i n g as ~rule out myocardial infarction (MI)" or '~chest pain of u n k n o w n etiology." This l a t t e r circumstance m a y hamper C C U e f f e c t i v e n e s s , d e p e n d i n g on occupancy rate and the severity i n the census.
INTRODUCTION The broad range of etiologies and severity i n p a t i e n t s with chest pain, from i m m e d i a t e l i f e - t h r e a t e n i n g to the clinically m u n d a n e , creates a difficult clinical problem for emergency physicians. 1 F u r t h e r m o r e , the clinical signs a n d symptoms as well as the basic laboratory assessment are noted for l a c k of s e n s i t i v i t y a n d
From the Division of Emergency Medicine,* Baltimore City Hospital, and the Health Services Research and Development Center, Division of Emergency Medicine,*t The Johns Hopkins Medical Institutions, Baltimore, Maryland. Supported by grant HS01310 from the •National Center for Health Services ReSearch, DHEW, to the Johns Hopkins Health Services Research and Develop-
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specificity. 2 The p a t i e n t with atypical moderate pain and a n o r m a l electrocardiogram (EKG) and chest x-ray film m a y be h a v i n g u n s t a b l e a n g i n a and be at risk of sudden death. On the other hand, a p a t i e n t with typical "ischemic" p a i n and nonspecific E K G a b n o r m a l i t i e s m a y merely have a "chest-wall syndrome. ''3,4 Killip et aP found a 25% m o r t a l i t y
ment Center, Johns Hopkins University. Presented at the annual University Association for Emergency Medicine meeting in Kansas City, Missouri, May, 1977. Address for r e p r i n t s ~ e r n a r d Slosberg, MD, MPH, Division 6~ Emergency Med.icine, Baltimore City Hospital, 4940 Eastern Avenue, Baltimore, Maryland 21224.
A d m i t t i n g enough versus not adm i t t i n g too m a n y is a fine line. Schor et al 7 e v a l u a t e d the e m e r g e n c y dep a r t m e n t t r e a t m e n t in Israel of 1,578 cases referred for possible MI. T e n per cent of those with a n MI were ina d v e r t e n t l y discharged from the ED a n d 28% of a d m i s s i o n s were subs e q u e n t l y judged unnecessary. Since in this c o u n t r y m o s t e m e r g e n c y dep a r t m e n t p a t i e n t s are self-referred, it would be difficult to e x t r a p o l a t e
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t h e s e f i n d i n g s or d u p l i c a t e such a sample. The purpose of the p r e s e n t s t u d y is to develop a methodology to m o n i t o r overall e m e r g e n c y d e p a r t m e n t evalu a t i o n of p a t i e n t s w i t h chest pain. S i n c e a b s o l u t e m e a s u r e s of effectiveness are not available, two e m e r g e n c y d e p a r t m e n t s were chosen for a c o m p a r a t i v e analysis. The init i a l objectives were to c o m p a r e the p a t i e n t populations a n d the results of t r e a t m e n t of c h e s t pain, a d m i s s i o n rates, a n d s y m p t o m a t i c r e l i e f in discharged patients.
METHODS Seven h u n d r e d a n d one consecutive p a t i e n t s w i t h the c o m p l a i n t of chest p a i n p r e s e n t i n g at the Baltim o r e C i t y H o s p i t a l (BCH) or t h e J o h n s H o p k i n s H o s p i t a l (JHH) were selected for t h e study. The study cove r e d t h e t i m e p e r i o d O c t o b e r 23, 1976 to N o v e m b e r 23, 1976. A pat i e n t was included if chest pain was a single c o m p l a i n t or p a r t of a m u l t i p l e c o m p l a i n t received by an e m e r g e n c y medical t e c h n i c i a n (EMT), a nurse or emergency department registrar. In a d d i t i o n to basic c h a r a c t e r i s t i c s (Figure), the h o s p i t a l s differ organi z a t i o n a l l y for t h e u n s c h e d u l e d pat i e n t w i t h a p r e s u m e d m i n o r problem. A t J H H , t h e r e is a p r i m a r y care c e n t e r (PCC) in an a d j a c e n t b u i l d i n g t h a t functions 9 am to 5 pro, Monday t h r o u g h Friday. P a t i e n t s m a y "walk in" directly to the PCC for care and also m a y be referred t h e r e from the e m e r g e n c y d e p a r t m e n t . At BCH all u n s c h e d u l e d p a t i e n t s are seen in the e m e r g e n c y d e p a r t m e n t . In order to create c o m p a r a b l e samples, the J H H s a m p l e i n c l u d e s p a t i e n t s from t h e PCC and the e m e r g e n c y d e p a r t m e n t . The e m e r g e n c y d e p a r t m e n t records of all p a t i e n t s were a b s t r a c t e d to obt a i n d a t a on socioeconomic, demog r a p h i c a n d c l i n i c a l v a r i a b l e s . The signs, s y m p t o m s , a n d r e s u l t s of all clinical tests were recorded. For t h o s e p a t i e n t s d i s c h a r g e d home, a telephone or p e r s o n a l i n t e r v i e w was c o n d u c t e d two w e e k s a f t e r t h e e m e r g e n c y d e p a r t m e n t visit. This interview a s c e r t a i n e d the need for unscheduled m e d i c a l care, c h a n g e s in s y m p t o m levels a n d disability, ie, int e r f e r e n c e w i t h the p a t i e n t ' s u s u a l a c t i v i t i e s . F o r t h e p a t i e n t s hos-
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HOSPITALS Baltimore City Hospital 1) C i t y - o p e r a t e d ; affiliated
Johns Hopkins Hospital
university
1) University hospital 2) 1200 beds
2) 600 beds
3) L o c a t i o n - - i n n e r city indigent area
3) L o c a t i o n - - l o w e r middle c l a s s - industrial
4) ED use - - 92,000 patients/ year
4) ED use - - 46,800 patients/ year
5) ED staffing - - house staff with teaching attendings
5) ED staffing - - house staff with teaching attendings
F i g u r e . Study hospital characteristics c a n t l y different between the hospitals (Table 1).
Table 1 INCIDENCE OF CHEST PAIN No.
Percent
BCH JHH
236 465
6.4 6.6
TOTAL:
701
6.5
Patient Characteristics
pitalized at t h e visit, an a b s t r a c t of the i n p a t i e n t record was o b t a i n e d inc l u d i n g the r e s u l t s of clinical e x a m i nations, p r i n c i p a l l y the E K G and enz y m e s t u d i e s . T h e l e n g t h of hosp i t a l i z a t i o n a n d all d i s c h a r g e diagnoses were recorded. Statistical differences between ratios were tested u s i n g chi s q u a r e analysis. Patient symptoms were coded u s i n g t h e N a t i o n a l A m b u l a t o r y Care S u r v e y Classification s a n d diagnostic i n f o r m a t i o n was coded by the H-ICDA.
RESULTS The Sample and Incidence of Chest Pain The d i s t r i b u t i o n of the sample and the incidence of the c o m p l a i n t show t h a t the incidence was not signifi-
Age. By chi s q u a r e analysis, the age d i s t r i b u t i o n s a r e significantly d i f f e r e n t , i n d i c a t i n g t h e J H H pa. t i e n t s are y o u n g e r w i t h a prominent proportion u n d e r age 30 (Table 2). Race and Sex. Sixty-one per cent of t h e p a t i e n t s w e r e b l a c k a n d 56~ were women. These r a t i o s do not differ s i g n i f i c a n t l y from a l l patients u s i n g t h e e m e r g e n c y department.S T h e r e w e r e v e r y s i g n i f i c a n t differences in the race and sex proportions b e t w e e n h o s p i t a l s (Table 3). Clinical Characteristics. Three m e a s u r e s were used to assess severi t y in t h e two cohorts: 1) need for a m b u l a n c e service; 2) a positive history ~or cardiac disease, and 3) the presence of h e a r t disease as an exp l a n a t i o n for t h e chest pain. Ambul a n c e t r a n s p o r t w a s r e q u e s t e d by 17% of t h e o v e r a l l s a m p l e with no noted difference b e t w e e n hospitals. T w e n t y - t h r e e per cent were n o t e d to have a prior h i s t o r y of h e a r t disease a n d in 18% c a r d i a c d i s e a s e was t h o u g h t to be t h e r e a s o n for chest p a i n at t h e p r e s e n t visit. The propor-
Table 2 AGE DISTRIBUTION OF STUDY S A M P L E S JHH
BCH AGE
No.
%
No,
%
18-30 31-40 41-50 51-6O 61-70 70
47 39 42 53 28 26
20 16 " 18 23 12 11
142 82 72 86 42 4O
31 18 16 18 9 8
236
100
465
100
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Table 3 RACE AND SEX DISTRIBUTION (%) Race BCH JHH Sex BCH JHH
Table 4 MEASURES OF SEVERITY (%)
Black
White
24 80
76 20
Female
Male
47 60
53 40
tiqn with a h i s t o r y of cardiac disease or an acute cardiac diagnosis was not different b e t w e e n the two h o s p i t a l s (Table 4).
Admission rates. The o v e r a l l admission r a t e for t h e c o h o r t of patients was 20%, which is considerably higher t h a n the a d m i s s i o n r a t e for e m e r g e n c y d e p a r t m e n t p a t i e n t s 2 The BCH r a t e was 25.8% and J H H was 17.2%, a s t a t i s t i c a l l y significant difference.
Follow-up of discharged patients. A questionnaire response r a t e of 82% was achieved on the sample of chest pain p a t i e n t s d i s c h a r g e d from t h e emergency d e p a r t m e n t . One d e a t h was identified. Thirty-five percent of the i n d i v i d u a l s c o n t a c t e d h a d t h e same or more p a i n t h a n at t h e i r initial visit. These r e s u l t s in discharged patients were n o t s i g n i f i c a n t l y different b e t w e e n t h e two hospitals. DISCUSSION During the course of p u r s u i n g the study's m a j o r o b j e c t i v e - - t h e development of a nonintervening method to e v a l u a t e e m e r g e n c y department p e r f o r m a n c e c h a r a c t e r i s tics' of p a t i e n t s w i t h chest p a i n - - ins t i t u t i o n a l d i f f e r e n c e s were d e t e r mined. T h e i n c i d e n c e of t h e complaint was the s a m e a t both hospitals and it is u n c h a n g e d from a s i m i l a r study conducted at J H H in 1974.1° The age, sex, a n d r a c i a l c h a r a c t e r i s tics were not s i g n i f i c a n t l y different from o t h e r s a m p l e s of e m e r g e n c y dep a r t m e n t u s e r s of t h e s a m e e m e r gency d e p a r t m e n t s 2 H o w e v e r , t h e BCH s a m p l e is more affluent, older, tends to h a v e a h i g h e r p r o p o r t i o n of males, a n d h a s a v e r y d i f f e r e n t racial c o m p o s i t i o n f r o m t h e J H H I Sample. Despite these socioeconomic differences, the m e a s u r e s of medical
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Ambulance use Heart disease Cardiac diagnosis at visit
significance used: 1) the need for ambulance t r a n s p o r t , 2) the proportion of t h e s a m p l e w i t h k n o w n c a r d i a c disease, a n d 3) t h e proportion of those w i t h c a r d i a c d i a g n o s i s a t the visit, showed no difference between the two hospitals. B a l t i m o r e h a s a sophisticated public e m e r g e n c y a m b u l a n c e s y s t e m w i t h l i b e r a l access. The s e r v i c e is free a n d m o s t all p a t i e n t s who request t h e service are t r a n s p o r t e d to t h e n e a r e s t hospital. 11 The m e a s u r e of a m b u l a n c e use is therefore more closely r e l a t e d to c o n s u m e r r a t h e r than professional perception of u r g e n c y or s e v e r i t y . Socioeconomic, educational, and cultural factors l i k e l y p l a y a m o r e s i g n i f i c a n t role t h a n a c t u a l m e d i c a l severity. T h i s s t u d y c o n f i r m s the c l i n i c a l n o t i o n t h a t a s m a l l p r o p o r t i o n of chest pain p a t i e n t s have an u r g e n t or e m e r g e n c y problem, a history of card i a c d i s e a s e , or a n a c u t e c a r d i a c diagnosis. T h e c h a r a c t e r i s t i c s of t h e c h e s t p a i n cohorts at t h e .two hospitals are t h o u g h t to be r e p r e s e n t a t i v e of the p o p u l a t i o n s l i v i n g n e a r each hospital. In B a l t i m o r e , this is reinforced b y the n e a r e s t h o s p i t a l rule of the public a m b u l a n c e system. The o v e r a l l a d m i s s i o n r a t e s for the chest p a i n p a t i e n t s are h i g h e r t h a n for all e m e r g e n c y d e p a r t m e n t u s e r s 2 The crude r a t e differs s i g n i f i c a n t l y b e t w e e n t h e two h o s p i t a l s , d e s p i t e s i m i l a r i t i e s of s e v e r a l m e a s u r e s of s e v e r i t y . Two a d d i t i o n a l p h a s e s of t h i s s t u d y will explore the m e a n i n g of this difference a n d put it into a b r o a d e r perspective. First, a m u l t i p l e r e g r e s s i o n model is being developed to a l l o t t h e effects of d e m o g r a p h i c a n d medical v a r i a b l e s on the admission r a t e s and s e c o ~ y , the f a t a l i t y r a t e s in the m o n t h following emergency department discharge will be a s c e r t a i n e d from a n y d e a t h r e c -
BCH
JHH
TOTAL
20 20.8
15.7 23.6
17 23
21
17
18
ords for t h e cohort. A p l a n n e d parallel quality of care study using this data base will estimate and compare the proportion j u d g e d to be " i n a p p r o p r i a t e l y " d i s c h a r g e d from the e m e r g e n c y d e p a r t m e n t a n d those " u n n e c e s s a r i l y " admitted. The s t u d y will use "blind" p h y s i c i a n j u d g e s of case a b s t r a c t s a n d actual E K G s . E x p e r i e n c e w i t h the home quest i o n n a i r e is p r o m i s i n g ; a 82% response r a t e was achieved. I n i t i a l l y , we hoped t h a t the d a t a could help est i m a t e t h e p r o p o r t i o n of i n a p p r o priate discharges but this was not r e a l i z e d s i n c e o n l y one d e a t h w a s identified. It is very likely t h a t the adverse results would aggregate a m o n g t h e n o n r e s p o n d e n t s . There= fore, in t h e future, d e a t h records and i m p l i c i t p h y s i c i a n j u d g e m e n t s will be used for such e s t i m a t e s . The major outcome r e p o r t e d from the questionn a i r e to date, ie, s y m p t o m r e l i e f at two weeks, is sobering but the medical c h a r a c t e r i s t i c s of these individuals will h a v e to be f u r t h e r analyzed. Due to the p o t e n t i a l of i m p r o v i n g p e r f o r m a n c e when these studies are c o m p l e t e , s e v e r a l i n t e r v e n t i o n s in o u r e m e r g e n c y d e p a r t m e n t practice a r e b e i n g considered. A m o n g t h e m are a systematic educational report of s t u d y r e s u l t s and a new a p p r o a c h to care based on e l i c i t i n g two indep e n d e n t m e d i c a l histories on p a t i e n t s w i t h c h e s t pain. T h i s l a t t e r w o u l d t e n d to i m p r o v e the v a l i d i t y of the subjective clinical data, often the m a j o r aspect of the d a t a base used for the admission decision. Also, the l i k e l i h o o d of a n i n a p p r o p r i a t e disc h a r g e could be further decreased if t h e two i n d e p e n d e n t a s s e s s m e n t s were judged conservatively. Furt h e r m o r e , a periodic review u s i n g this m e t h o d o l o g y m a y be w o r t h w h i l e but for efficiency it should be l i m i t e d to the higher risk chest pain group r a t h e r t h a n the e n t i r e u n i v e r s e of such p a t i e n t s . 447/29
REFERENCES 1. Lichstein E, Seckler S: Evaluation of acute chest pain. Med Clin North A m 57:1481-1490, 1973. 2. Hurst JW: Symptoms Due to Heart Disease, in The Heart, ed 3. New York, McGraw-Hill, 1974, p 140.
5. Killip T, Kimball JT: A survey of the coronary unit. Concepts and results. Prog Cardiovasc Dis 11:45, 1968. 6. Norris RM, Caughey D, Mercer C, et al: Coronary prognostic index for predicting survival aider recovery from acute myocardial infarction. Lancet 2:485, 1970.
3. Braunwald E, Harrison TR: Principles of Internal Medicine, ed 8. New York, McGraw-Hill, 1977, pp 28-33.
7. Schor position from an 941-943,
4. Conti CR, Griffith L, Ross R: Thoracic pain and angina pectoris, in Principles and Practice of Medicine. New York, Apple-Century Crofts, 1976, pp 325-340.
8. The N a t i o n a l A m b u l a t o r y Medical Care Survey: Symptom Classification. DHEW Publication 74-1337, Rockville, Maryland, July, 1976.
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S, Behar S, Modan B, et al: Disof presumed coronary patients e m e r g e n c y room. J A M A 236: 1976.
9. Perspective study of patients presenting with chest pain at the Johns Hopkins Hos. pital and Baltimore City Hospital, October 23 - November 23, 1976. EMS Research Program Projects, Health Services Re. search and Development Center, Johns Hopkins University, Baltimore. 10. Twenty most frequent complaints, ar. ranged by frequency as single complaints. EMS Research Program Projects, Health S e r v i c e s R e s e a r c h a n d Development Center, Johns Hopkins University, BaI. timore, October, 1974. 11. Emergency Ambulance Service. Baltimore City Fire Department, Baltimore, 1965.
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