Electroencephalography and Clinical Neurophysiology, 1978, 4 4 : 5 1 8 - - 5 2 2
518
© Elsevier/North-Holland Scientific Puubiishers Ltd. Clinical Note 'ALPHA-PATTERN
COMA' AND SURVIVAL
AFTER
CARDIAC ARREST
MOGENS MOLLER
Departments of Medicine B and Clinical Neurophysiology, Odense University Hospital (Denmark) (Accepted for publication: October 24, 1977)
Several case reports and small series comprising =omatose patients with an EEG pattern of dominant activity in the alpha frequency range have been published since 1953. The pattern differs from the usual conscious pattern in its topographic distribution and the fact that it is unaffected by afferent stimuli. 'Alpha-pattern coma' has been described in patients with vascular brain-stem lesions (Loeb and Poggio 1953; Marquardsen and Harvald 1964; Westmoreland et al. 1975), following traumatic brain-stem infarct {Chatrian et al. 1964), anoxic brain damage (Binnie
et al. 1970; Brierly et al. 1971; Vignaendra et al. 1974; Westmoreland et al. 1975; Chokroverty 1975) and following cardiac arrest after accidental electrocution (Grindal and Suter 1975). Survival has only been observed in five of the approximately 100 published cases. A case is reported, on this basis, of a man who survived with a rhythm of alpha frequency during coma after cardiac arrest in connection with myocardial infarction.
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28
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Pig. 1. On the day of cardiac arrest: Regular 8--8.5-c/sec activity over both hemispheres, most pronounced in the !ronto-temporal regions. No changes in connection with stimuli. The patient was comatose with typical torsion ~pasms.
26/M
39/M
Mller et al. (1977)
High voltage injury
28/M
Grindal and Suter (1975)
Anaphylactic
48]M
Chokroverty (1975) Grindal and Suter (1975)
Acute myocardial infarction
High voltage injury
Diabetic coma
53/M
Chokroverty (1975)
Cause of cardiac arrest (CA)
Age/sex
Author
approx. 18 h
24 h
18 h
24--48 h
24--36 h
Time from CA To EEG
Comatose, are flexic
Comatose, hyperactive reflexes, no Babinski
Comatose, hypertonic reflexes, no Babinski
8 c/sec particularly fronto-temporal
10--11 c/sec particularly fronto-central 9--10 c/sec diffuse 7--9 c/sec particularly fronto-central 9--11 c/sec fro n to -cent ral
Comatose, areflexic
Comatose, areflexic
EEG findings
Condition on recording EEG
Clinical summary of 5 patients who survived after 'alpha-pattern coma'.
TABLE I
Conscious 8 days after CA, Died o f new CA. No information on mental condition at death. Discharged with mild memory impairment. Increasingly agitated from 3--22 day, Verbal contact day 22, irreparable impairment of memory. Conscious after 18 days. Difficulty with spatial and temporal orientation. Conscious after 3 days. Severe memory impairment on discharge.
Outcome
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28
11-11-71
Fig. 2. T h r e e d a y s a f t e r t h e cardiac arrest: o n l l - - 1 2 - c / s e c r h y t h m o f scanty to m e a n d i s p e r s i o n , m i x e d w i t h a fast 18-c/sec activity o f low voltage. No low f r e q u e n c y activity is seen. T h e p a t i e n t was s o m n o l e n t .
Case r e p o r t T h e p a t i e n t was a previously h e a l t h y 39oyear-old m a n w h o , a f t e r a s h o r t p e r i o d o f r e t r o s t e r n a l oppression, d e v e l o p e d cardiac arrest o u t s i d e hospital. A t t e m p t s at r e s u s c i t a t i o n using e x t e r n a l h e a r t massage a n d v e n t i l a t i o n b y t h e m o u t h - t o - m o u t h m e t h o d were i m m e d i a t e l y m a d e b y a l a y m a n . On arrival at t h e e m e r g e n c y r o o m 7 rain l a t e r t h e ECG s h o w e d vent r i c u l a r fibrillation, a n d r e s u s c i t a t i o n was c o n t i n u e d according to the normal procedure of the department. T h e c i r c u l a t i o n was re-established a p p r o x . 30 rain a f t e r t h e o n s e t o f cardiac arrest, f o l l o w i n g several DC shocks. T h e p a t i e n t was co~latose, w i t h o u t s p o n t a n e o u s r e s p i r a t i o n a n d s h o w e d n o reflexes at t h e t i m e o f t h e first E E G , a p p r o x . 18 h a f t e r cardiac arrest. E E G ' s were r e c o r d e d using a 1 6 - c h a n n e l a p p a r a t u s , t h e 10120 e l e c t r o d e system, and a rec o r d i n g t i m e o f 30 rain. T h e first E E G (Fig. 1) s h o w e d a fairly regular r h y t h m o f a l p h a f r e q u e n c y (8--8.5 c/sec), while t h e l a t e r o n e s are s h o w n in Fig. 2 a n d 3. T h e d u r a t i o n o f t h e c o m a was 3 days, a f t e r w h i c h t h e p a t i e n t gradually regained c o n s c i o u s n e s s a n d developed spontaneous respiration.
The patient had had an acute myocardial infarction a c c o r d i n g to t h e criteria o f t h e WHO. On t h e 1 5 t h day a f t e r a d m i s s i o n a n d d u r i n g m o n i t o r i n g he suffered f r o m t w o e p i s o d e s o f v e n t r i c u l a r fibrillation, b o t h a t t a c k s b e i n g c o n v e r t e d to sinus r h y t h m by single DC c o u n t e r shocks. P s y c h i a t r i c e x a m i n a t i o n 6 weeks after cardiac arrest s h o w e d t h e p a t i e n t to be i n c o h e r e n t and d e r a n g e d ; h e had severe a m n e s i a a n d was totally allo-psychically d i s o r i e n t a t e d a n d also e m o t i o n a l l y neutral. He was t r a n s f e r r e d to a p s y c h i a t r i c hospital, f r o m w h i c h he was d i s c h a r g e d to his h o m e 2 m o n t h s later. Six m o n t h s after t h e cardiac arrest psychological e x a m i n a t i o n revealed t h a t t h e p a t i e n t was o r i e n t a t e d w i t h respect to place a n d person, b u t n o t to time. He was e v a l u a t e d as having b e e n i n t e l l i g e n t p r i o r to t h e illness. Signs o f d e m e n t i a were p r e s e n t , his ability to r e t a i n a given a m o u n t o f d a t a was r e d u c e d and m e m o r y tests revealed i m p a i r m e n t o f logical, visual a n d associative f u n c t i o n s . H o w e v e r he was, o n t h e w h o l e , able to l o o k a f t e r himself. T h e p a t i e n t is still alive 6 years a f t e r t h e episode o f cardiac arrest.
'ALPHA-PATTERN COMA' AND SURVIVAL
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O.S. 2209/71-72
28
29-11-71
Fig. 3. T w e n t y d a y s a f t e r t h e cardiac arrest: a low voltage ( 3 0 - - 5 0 u V ) tracing w i t h s c a n t y , d o m i n a n t activity at 9 - - 1 0 c/sec m i x e d w i t h diffuse 4--7-c/sec activity. T h e p a t i e n t was conscious.
Discussion Details o f 4 o f t h e 5 previously r e p o r t e d survivors are s h o w n in t h e table. No t h o r o u g h d e s c r i p t i o n is available o f the 5th case (Binnie et al. 1970). It s h o u l d be n o t e d t h a t Briefly et al. ( 1 9 7 1 ) o b s e r v e d i n t e r m i t t e n t a l p h a r h y t h m in a c o m a t o s e p a t i e n t w h o survived for 3 m o n t h s in a vegetative state w i t h a m a i n l y isoelectric EEG. T h e r e is n o d o u b t t h a t an ' a l p h a - p a t t e r n c o m a ' i n d i c a t e s a very p o o r prognosis. O f t h e a p p r o x i m a t e 100 r e p o r t e d cases o n l y 5 survived the acute phase. In a c o n s e c u t i v e series o f 185 p a t i e n t s w i t h acute m y o cardial i n f a r c t i o n a n d an episode o f clinical cardiac arrest ' a l p h a - p a t t e r n c o m a ' was seen in 35 a n d o f t h e s e o n l y t h e p r e s e n t p a t i e n t survived (M$11er et al. in press). In t h e o n l y o t h e r large series w i t h a t o t a l o f 25 p a t i e n t s w i t h a n o x i c b r a i n d a m a g e a f t e r cardiac arrest ( V i g n a e n d r a e t al. 1 9 7 4 ; C h o k r o v e r t y 1 9 7 5 ; W e s t m o r e l a n d et al. 1 9 7 5 ) a r h y t h m o f a l p h a freq u e n c y was d e s c r i b e d as b e i n g m o s t l y w i d e s p r e a d a n t e r i o r l y , o f t e n f r o n t o - c e n t r a l l y , w h e r e a s t h e locali z a t i o n in p a t i e n t s w i t h vascular b r a i n - s t e m a f f e c t i o n s
is p o s t e r i o r ( W e s t m o r e l a n d et al. 1975). T h u s t h e r e is no possibility o f defining the various p r o g n o s t i c g r o u p s f r o m the t o p o g r a p h y o f t h e a l p h a f r e q u e n c y rhythm. As can be seen f r o m t h e table t h e E E G s o f t h e 5 survivors were r e c o r d e d s h o r t l y a f t e r cardiac arrest. This does n o t a p p e a r t o be t h e case to a n y great e x t e n t in t h e non-surviving p a t i e n t s with ' a l p h a - p a t t e r n c o m a ' . H o w e v e r we have, in t h e above m e n t i o n e d 35 p a t i e n t s w i t h ' a l p h a - p a t t e r n c o m a ' , r e c o r d e d the E E G w i t h i n 24 h o f the cardiac arrest in 10 o f t h e m , o f w h o m o n l y the p r e s e n t p a t i e n t survived. T h e r e d o e s n o t a p p e a r to be any e x p l a n a t i o n as to w h y r h y t h m o f a l p h a f r e q u e n c y o c c u r s in some c o m a t o s e p a t i e n t s a n d n o t in o t h e r s , n e i t h e r is t h e r e any possibility f r o m t h e p r e s e n t case o f defining the few p a t i e n t s w h o will survive.
Summary A ease o f survivaJ despite an EEG in the alpha range d u r i n g c o m a after cardiac arrest in c o n n e c t i o n with acute m y o c a r d i a l i n f a r c t i o n is r e p o r t e d . T h e o t h e r
522 5 published cases are referred to. On the basis of the available literature it is concluded that it is impossible to determine the few patients who will survive despite 'alpha-pattern coma'. Rdsum6 Coma 'de type alpha' et survie apr~s arret du coeur
On d~!crit ici un cas de survie, apr6s un coma avec EEG dans la bande alpha, dfi ~ un arr~t cardiaque 1i6 a un infarctus aigu. On examine h ce propos les 5 cas pr6c6demment publi6s, et l'on conclut h I'impossibilit6 d'6mettre un pronostic quant fi la survie de patients dans un tel type de coma. References
Binnie, C.D., Prior, P.F., Lloyd, D.S.L., Scott, D.F. and Margerison, J.H. Electroencephalographic prediction of fatal anoxic brain damage after resuscitation from cardiac arrest. Brit. med. J. 1970, IV: 265--268. Brierly, J.B., Adams, J.H., Graham, D.I. and Simpson, J.A. Neocortical death after cardiac arrest. A clinical, neurophysiological, and neuropathological report of two cases. Lancet, 1971, 11 : 560--565. Chatrian, G.E., White, jr., L.E., Shaw, C.-M. EEG pattern resembling wakefulness in unresponsive decerebrate state following traumatic brain-stem infarct.
M. MOLEER Electroenceph. clin. Neurophysiol., 1964, 16: 285--289. Chokroverty, S. "Alpha-like" rhythms in electroencephalograms in coma after cardiac arrest. Neurology (Minneap.), 1975, 25: 655--663. Grindal, A.B. and Suter, C. 'Alpha-pattern coma' in high voltage electrical injury. Electroenceph. clin. Neurophysiol., 1975, 38: 521--526. Loeb. C. and Poggio, G. Electroencephalograms in a case with pontomesencephalic haemorrhage. Electroenceph. clin. Neurophysiol. 1953, 5: 295--296. Marquardsen, I. and Harvald, B. The electroencephalogram in acute vascular lesions o f the brain stem and the cerebellum. Acta neurol, scand. 1964, 40: 58--68. Moller, M., Holm, B., Sindrup, E. and Lyager Nielsen, B. Electroencephalographic prediction of anoxic brain damage after resuscitation from cardiac arrest in patients with acute myocardial infarction. Acta reed. scand., in press. Vignaendra, V., Wilkus, R.J., Copass, M.K. and Chatrian, G.E. Electroencephalographic rhythms of alpha frequency in comatose pateints after cardiopulmonary arrest. Neurology (Minneap.), 1974, 24: 582--588. Westmoreland, B.F., Klass, D.W., Sharbrough, F.W. and Reagan, T.J. Alpha coma. Electroeneephalographic, clinical, pathologic and etiologic correlations. Arch. Neurol. (Chic.) 1975, 32: 713--718.
518
© Elsevier/North-Holland Scientific Puubiishers Ltd. Clinical Note 'ALPHA-PATTERN
COMA' AND SURVIVAL
AFTER
CARDIAC ARREST
MOGENS MOLLER
Departments of Medicine B and Clinical Neurophysiology, Odense University Hospital (Denmark) (Accepted for publication: October 24, 1977)
Several case reports and small series comprising =omatose patients with an EEG pattern of dominant activity in the alpha frequency range have been published since 1953. The pattern differs from the usual conscious pattern in its topographic distribution and the fact that it is unaffected by afferent stimuli. 'Alpha-pattern coma' has been described in patients with vascular brain-stem lesions (Loeb and Poggio 1953; Marquardsen and Harvald 1964; Westmoreland et al. 1975), following traumatic brain-stem infarct {Chatrian et al. 1964), anoxic brain damage (Binnie
et al. 1970; Brierly et al. 1971; Vignaendra et al. 1974; Westmoreland et al. 1975; Chokroverty 1975) and following cardiac arrest after accidental electrocution (Grindal and Suter 1975). Survival has only been observed in five of the approximately 100 published cases. A case is reported, on this basis, of a man who survived with a rhythm of alpha frequency during coma after cardiac arrest in connection with myocardial infarction.
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28
9-11-71
Pig. 1. On the day of cardiac arrest: Regular 8--8.5-c/sec activity over both hemispheres, most pronounced in the !ronto-temporal regions. No changes in connection with stimuli. The patient was comatose with typical torsion ~pasms.
26/M
39/M
Mller et al. (1977)
High voltage injury
28/M
Grindal and Suter (1975)
Anaphylactic
48]M
Chokroverty (1975) Grindal and Suter (1975)
Acute myocardial infarction
High voltage injury
Diabetic coma
53/M
Chokroverty (1975)
Cause of cardiac arrest (CA)
Age/sex
Author
approx. 18 h
24 h
18 h
24--48 h
24--36 h
Time from CA To EEG
Comatose, are flexic
Comatose, hyperactive reflexes, no Babinski
Comatose, hypertonic reflexes, no Babinski
8 c/sec particularly fronto-temporal
10--11 c/sec particularly fronto-central 9--10 c/sec diffuse 7--9 c/sec particularly fronto-central 9--11 c/sec fro n to -cent ral
Comatose, areflexic
Comatose, areflexic
EEG findings
Condition on recording EEG
Clinical summary of 5 patients who survived after 'alpha-pattern coma'.
TABLE I
Conscious 8 days after CA, Died o f new CA. No information on mental condition at death. Discharged with mild memory impairment. Increasingly agitated from 3--22 day, Verbal contact day 22, irreparable impairment of memory. Conscious after 18 days. Difficulty with spatial and temporal orientation. Conscious after 3 days. Severe memory impairment on discharge.
Outcome
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M. M(~LLER
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1oo ~v [ _ _ lsec t.c..O,3sec O.S. 2056/71-72
28
11-11-71
Fig. 2. T h r e e d a y s a f t e r t h e cardiac arrest: o n l l - - 1 2 - c / s e c r h y t h m o f scanty to m e a n d i s p e r s i o n , m i x e d w i t h a fast 18-c/sec activity o f low voltage. No low f r e q u e n c y activity is seen. T h e p a t i e n t was s o m n o l e n t .
Case r e p o r t T h e p a t i e n t was a previously h e a l t h y 39oyear-old m a n w h o , a f t e r a s h o r t p e r i o d o f r e t r o s t e r n a l oppression, d e v e l o p e d cardiac arrest o u t s i d e hospital. A t t e m p t s at r e s u s c i t a t i o n using e x t e r n a l h e a r t massage a n d v e n t i l a t i o n b y t h e m o u t h - t o - m o u t h m e t h o d were i m m e d i a t e l y m a d e b y a l a y m a n . On arrival at t h e e m e r g e n c y r o o m 7 rain l a t e r t h e ECG s h o w e d vent r i c u l a r fibrillation, a n d r e s u s c i t a t i o n was c o n t i n u e d according to the normal procedure of the department. T h e c i r c u l a t i o n was re-established a p p r o x . 30 rain a f t e r t h e o n s e t o f cardiac arrest, f o l l o w i n g several DC shocks. T h e p a t i e n t was co~latose, w i t h o u t s p o n t a n e o u s r e s p i r a t i o n a n d s h o w e d n o reflexes at t h e t i m e o f t h e first E E G , a p p r o x . 18 h a f t e r cardiac arrest. E E G ' s were r e c o r d e d using a 1 6 - c h a n n e l a p p a r a t u s , t h e 10120 e l e c t r o d e system, and a rec o r d i n g t i m e o f 30 rain. T h e first E E G (Fig. 1) s h o w e d a fairly regular r h y t h m o f a l p h a f r e q u e n c y (8--8.5 c/sec), while t h e l a t e r o n e s are s h o w n in Fig. 2 a n d 3. T h e d u r a t i o n o f t h e c o m a was 3 days, a f t e r w h i c h t h e p a t i e n t gradually regained c o n s c i o u s n e s s a n d developed spontaneous respiration.
The patient had had an acute myocardial infarction a c c o r d i n g to t h e criteria o f t h e WHO. On t h e 1 5 t h day a f t e r a d m i s s i o n a n d d u r i n g m o n i t o r i n g he suffered f r o m t w o e p i s o d e s o f v e n t r i c u l a r fibrillation, b o t h a t t a c k s b e i n g c o n v e r t e d to sinus r h y t h m by single DC c o u n t e r shocks. P s y c h i a t r i c e x a m i n a t i o n 6 weeks after cardiac arrest s h o w e d t h e p a t i e n t to be i n c o h e r e n t and d e r a n g e d ; h e had severe a m n e s i a a n d was totally allo-psychically d i s o r i e n t a t e d a n d also e m o t i o n a l l y neutral. He was t r a n s f e r r e d to a p s y c h i a t r i c hospital, f r o m w h i c h he was d i s c h a r g e d to his h o m e 2 m o n t h s later. Six m o n t h s after t h e cardiac arrest psychological e x a m i n a t i o n revealed t h a t t h e p a t i e n t was o r i e n t a t e d w i t h respect to place a n d person, b u t n o t to time. He was e v a l u a t e d as having b e e n i n t e l l i g e n t p r i o r to t h e illness. Signs o f d e m e n t i a were p r e s e n t , his ability to r e t a i n a given a m o u n t o f d a t a was r e d u c e d and m e m o r y tests revealed i m p a i r m e n t o f logical, visual a n d associative f u n c t i o n s . H o w e v e r he was, o n t h e w h o l e , able to l o o k a f t e r himself. T h e p a t i e n t is still alive 6 years a f t e r t h e episode o f cardiac arrest.
'ALPHA-PATTERN COMA' AND SURVIVAL
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O.S. 2209/71-72
28
29-11-71
Fig. 3. T w e n t y d a y s a f t e r t h e cardiac arrest: a low voltage ( 3 0 - - 5 0 u V ) tracing w i t h s c a n t y , d o m i n a n t activity at 9 - - 1 0 c/sec m i x e d w i t h diffuse 4--7-c/sec activity. T h e p a t i e n t was conscious.
Discussion Details o f 4 o f t h e 5 previously r e p o r t e d survivors are s h o w n in t h e table. No t h o r o u g h d e s c r i p t i o n is available o f the 5th case (Binnie et al. 1970). It s h o u l d be n o t e d t h a t Briefly et al. ( 1 9 7 1 ) o b s e r v e d i n t e r m i t t e n t a l p h a r h y t h m in a c o m a t o s e p a t i e n t w h o survived for 3 m o n t h s in a vegetative state w i t h a m a i n l y isoelectric EEG. T h e r e is n o d o u b t t h a t an ' a l p h a - p a t t e r n c o m a ' i n d i c a t e s a very p o o r prognosis. O f t h e a p p r o x i m a t e 100 r e p o r t e d cases o n l y 5 survived the acute phase. In a c o n s e c u t i v e series o f 185 p a t i e n t s w i t h acute m y o cardial i n f a r c t i o n a n d an episode o f clinical cardiac arrest ' a l p h a - p a t t e r n c o m a ' was seen in 35 a n d o f t h e s e o n l y t h e p r e s e n t p a t i e n t survived (M$11er et al. in press). In t h e o n l y o t h e r large series w i t h a t o t a l o f 25 p a t i e n t s w i t h a n o x i c b r a i n d a m a g e a f t e r cardiac arrest ( V i g n a e n d r a e t al. 1 9 7 4 ; C h o k r o v e r t y 1 9 7 5 ; W e s t m o r e l a n d et al. 1 9 7 5 ) a r h y t h m o f a l p h a freq u e n c y was d e s c r i b e d as b e i n g m o s t l y w i d e s p r e a d a n t e r i o r l y , o f t e n f r o n t o - c e n t r a l l y , w h e r e a s t h e locali z a t i o n in p a t i e n t s w i t h vascular b r a i n - s t e m a f f e c t i o n s
is p o s t e r i o r ( W e s t m o r e l a n d et al. 1975). T h u s t h e r e is no possibility o f defining the various p r o g n o s t i c g r o u p s f r o m the t o p o g r a p h y o f t h e a l p h a f r e q u e n c y rhythm. As can be seen f r o m t h e table t h e E E G s o f t h e 5 survivors were r e c o r d e d s h o r t l y a f t e r cardiac arrest. This does n o t a p p e a r t o be t h e case to a n y great e x t e n t in t h e non-surviving p a t i e n t s with ' a l p h a - p a t t e r n c o m a ' . H o w e v e r we have, in t h e above m e n t i o n e d 35 p a t i e n t s w i t h ' a l p h a - p a t t e r n c o m a ' , r e c o r d e d the E E G w i t h i n 24 h o f the cardiac arrest in 10 o f t h e m , o f w h o m o n l y the p r e s e n t p a t i e n t survived. T h e r e d o e s n o t a p p e a r to be any e x p l a n a t i o n as to w h y r h y t h m o f a l p h a f r e q u e n c y o c c u r s in some c o m a t o s e p a t i e n t s a n d n o t in o t h e r s , n e i t h e r is t h e r e any possibility f r o m t h e p r e s e n t case o f defining the few p a t i e n t s w h o will survive.
Summary A ease o f survivaJ despite an EEG in the alpha range d u r i n g c o m a after cardiac arrest in c o n n e c t i o n with acute m y o c a r d i a l i n f a r c t i o n is r e p o r t e d . T h e o t h e r
522 5 published cases are referred to. On the basis of the available literature it is concluded that it is impossible to determine the few patients who will survive despite 'alpha-pattern coma'. Rdsum6 Coma 'de type alpha' et survie apr~s arret du coeur
On d~!crit ici un cas de survie, apr6s un coma avec EEG dans la bande alpha, dfi ~ un arr~t cardiaque 1i6 a un infarctus aigu. On examine h ce propos les 5 cas pr6c6demment publi6s, et l'on conclut h I'impossibilit6 d'6mettre un pronostic quant fi la survie de patients dans un tel type de coma. References
Binnie, C.D., Prior, P.F., Lloyd, D.S.L., Scott, D.F. and Margerison, J.H. Electroencephalographic prediction of fatal anoxic brain damage after resuscitation from cardiac arrest. Brit. med. J. 1970, IV: 265--268. Brierly, J.B., Adams, J.H., Graham, D.I. and Simpson, J.A. Neocortical death after cardiac arrest. A clinical, neurophysiological, and neuropathological report of two cases. Lancet, 1971, 11 : 560--565. Chatrian, G.E., White, jr., L.E., Shaw, C.-M. EEG pattern resembling wakefulness in unresponsive decerebrate state following traumatic brain-stem infarct.
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