Behar. Res. Thu. Vol. 22. No. 2, pp. IO!-117. Printed tn Great Bntain. All rights reserved
0005-7967/84 $3.00 + 0.00 Q 1984 Pergamon Press Ltd
IN BLOOD PHOBICS
LARS-GBRAN &T,* ULF STERNER and INGA-LENA LINDAHL Psychiatric Research Center, Ulleriker Hospital, S-750 17 Uppsala, Sweden (Received 9 May 1983; accepled 7 July 1983)
Summary-Eighteen patients with blood phobia were shown a film of thoracic operations containing large amounts of blood. Their heart rate (HR) and blood pressure (BP) were measured continuously before, during and after the watching of the film. The group data showed a diphasic response; an increase in HR and BP from baseline to the beginning of the film, and then a sharp drop in these parameters with the lowest values 4min after the film was turned off. Individual data from 5 patients who fainted or were on the edge of doing so, showed massive bradycardia or drop in BP or both. In all of these patients at least one (range l-33) 5-set period of asystole was recorded. Possible theoretical explanations for this characteristic response pattern are discussed.
Phobia for blood, wounds and injuries has a relatively high prevalence in the general population. Agras, Sylvester and Oliveau (1969) found a figure of 3 l/ 1000 and Costello (1982) reported 45/ 1000 in an exclusively female population. Viewed against this background it is puzzling that so few empirical studies on blood phobia have been published. The authors are aware of only 11 case studies with patients applying different treatments, and three group studies on analog Ss. Another reason why researchers should be interested in blood phobia-is the unusual pattern of physiological responses that has been reported (e.g. Connolly, Hallam and Marks, 1976; Marks, 1981) for this group of phobics. Instead of the increases in heart rate (HR), respiration, EMG, skin conductance etc. that are typically seen in phobics (Marks, 1975), blood phobics show bradycardia, decreased blood pressure (BP) and often fainting, when confronted with the phobic stimuli (Cohn, Kron and Brady, 1976; Wardle and Jarvis, 1981). Graham, Kabler and Lunsford (1961) described the fainting in blood donors as a diphasic response. “The first phase is a reflection of anxiety, while the second phase begins with the sudden cessation of anxiety. It is suggested that physiologically the faint reflects the action of reflex mechanisms activated by the first phase, and left suddenly unopposed.” (p. 506). The empirical foundation for this specific response pattern is, however, meager and rests mainly on some studies of blood donors who have fainted while donating blood (Graham et al., 1961; Graham, 1961; Ruetz, Johnson, Callahan, Meade and Smith, 1967) of persons undergoing dental procedures (Taggart, Hedworth-Whitty, Carruthers and Gordon, 1976; Edmondson, Gordon, Lloyd, Meeson and Whitehead, 1978) and of persons watching violent films (Carruthers and Taggart, 1973). The only physiological assessments reported on blood-phobic patients are HR (Cohn ez al., 1976; Wardle and Jarvis, 1981), for which a large decrease has been reported, and skin resistance (Wardle and Jarvis, 1981) which declined following phobic exposure. In view of the paucity of research on physiological responses in blood phobics (only two case studies), a group study in order to ascertain how typical these specific responses are for a clinical sample of blood phobics seems warranted. The purpose of the present study was to investigate the HR and BP reactions before, during and after the confrontation of phobic stimuli. The specific hypothesis tested was that the blood phobics’ reactions should follow those of fainting blood donors. described by Graham et al. (1961) i.e. an initial increase in HR and BP compared to baseline, followed by sharp decreases in these parameters. *To whom all reprint requests should be addressed. 109
The Ss for this study were outpatients at the Ulleraker mental hospital. They were either referred by physicians to the ongoing phobia treatment project or applied for treatment themselves after an advertisment in the local newspaper. In order to be included in the study the patients had to fulfil1 the following inclusion criteria: (1) Be between 20-60 yrs of age. (2) Have as the major presenting complaint, anxiety in and avoidance of a large range of situations with blood, wounds and injuries. (3) A minimum of 1 yr duration of the phobia. (4) Have no other psychiatric problem in immediate need of treatment. (5) Have no psychotic or organic symptoms. (6) Have no heart or lung disease. (7) If any anxiolytic drugs were used the intake was to be constant throughout the study. (8) Not to receive any other kind of psychiatric or psychotherapeutic treatment during the study. Twenty-two patients were referred to the study and 18 (12 women and 6 men) of these could come to a screening interview during a specified period of time. All of these fulfilled the above inclusion criteria. Their mean age was 3 1.Oyr (range 214) and the mean duration of their phobias was 24.5 yr (range 13-35). Fourteen of the patients reported having fainted in the phobic situation, and the majority had fainted many times. Furthermore, 12 (67%) of the patients had close relatives with a strong fear or phobia of blood; in 10 cases it was the mother, in 1 the father and in 1 a brother. Thirteen of the patients were married or living together with a steady partner, 3 were single, and 2 were divorced. Eleven of the Ss worked full-time, 2 part-time and 5 were studying. All of the patients were handicapped in their private lives and/or vocational careers due to their phobia for blood, wounds or injuries. Procedure
The focus for this study is the cardiovascular reactions that the patients displayed during a behavioral test, which was performed during the last part of a screening interview. The first part of the interview aimed at ascertaining the patient’s suitability for the study and took about 30-40 min. After that the patients were informed that their heart rate (HR) and blood pressure (BP) would be measured for a IO-min period in order to get reliable data. During this baseline period they were not aware of the behavioral test that was to follow, and thus it is a fairly accurate estimate of the true resting HR and BP. After the baseline period the patient was instructed that a test would follow, with the purpose of measuring his/her physiological reactions when watching a film about surgical operations. Then the video equipment was pulled forward from behind a curtain, and placed 4 m in front of the patient. He/she was instructed to watch the film all the time, without closing the eyes or looking away. High-demand instructions were used and the importance of watching as much as possible of the film was emphasized. Finally, the patient was informed that if it became too uncomfortable he/she could turn the film off by pressing a button. This period took 3-4 min, including answering any questions the patient might have. Then followed the showing of the (silent) film, which took at maximum 30 min. It consisted of four different thoracic operations, and contained quite a large amount of blood. After the patient had turned-off or managed to watch. the whole film, a second baseline of 10 min followed. The entire assessment took at maximum 60 min including attachment and removal of electrodes etc. Assessment and apparatus
HR was measured continuously during the four periods: baseline 1 (Bl), instruction, test and baseline 2 (B2). This was done with a portable EKG-cassette recorder (Medilog 4-2, Oxford Instruments) worn in a belt around the waist, with one electrode attached to the sternum and the
Physiological responses in blood phobics
other to the fifth vertebrate on the left side, using Har 155 (Harco Electronics Ltd) disposable Ag/AgCl electrodes. The patient’s HR was recorded on Channel 2 and any sounds on Channel 1. The cassette was replayed afterwards via a PB-2 replay unit (Oxford Instruments) to a microcomputer (Luxor ABC-80), which was programmed to analyze the incoming signals after every lo-set period. Finally, the data were printed as beats per min (bpm) on a printer (Metric Model 8300 P). While replaying this data the experimenter could from the sounds on Channel 1 decide when the different periods of the test started and ended. The patient’s BP was assessed with an electronic BP-instrument (Medtek 410) every 2 min as it was considered hazardous to occlude the arm more often, especially since as many as 26 BP measurements might be done during 50min. The cuff contains a microphone to pick up the Korotkoff sounds, and this was placed over the brachical artery of the right arm. During the entire test situation the patient was seated in an armchair with a pillow under the right arm in order to have the measurement site at the same level as the heart. After each measurement the BP instrument digitally presented the systolic (SBP) and diastolic pressure (DBP) in mmHg, and these values were recorded by the experimenter. RESULTS
Four of the 18 Ss managed to watch the whole film (30 min) and also said that they did not find the test valid because of the artificial situation, all the assessment instruments etc. These patients’ data were excluded from the data analysis. Heart rate
The patients’ HR reactions are presented in Fig. 1. As can be seen in this figure there is a stable Bl, with a mean of 68.5 bpm, followed by a marked increase in HR during the instruction period. During the last minute of this period the patients’ mean HR was 77.0 bpm. At the beginning of the test period the HR stayed at about the same level, but then it dropped dramatically, down to a mean of 54.0 at the end of this period. During B2 the mean HR increased up to the same level as during Bl, but with considerably more variability. As described above the patients decided themselves when to turn the film off and this means that the curve for the test period in Fig. 1 is based on a progressively smaller number of patients as shown at the bottom of the figure. The form of the curve might thus be an artefact, too much influenced by a small number of persons. In order to correct for this possibility the data were collapsed into the following phases as shown in Fig. 2: the mean of Bl, the end of the instruction phase, the last minute before the patient turned the film off, irrespective of when this occurred, and 2,4,6, 8 and 10 min after the turn-off. In this way all patients’ data are included in each point of the curve. BI
MBase - End of llne instr.
At the turn-off
4 6 8 IO 2 Mmutes otter turn-off
Fig. 1. Mean HR during the different periods of the test.
Fig. 2. Mean HR during consecutive phases of the test.
SBP (left panel) and DBP (right different periods of the test.
6 12 162024282
I MBow-Endot mtr. I I”.
6 6 IO At the 2 4 turn -off Minutes after turn off
4. Mean SBP during consecutive phases of the test.
The analysis of variance (randomized block design; Kirk, 1968) yielded significant F-values for both the time (1;(7,119) = 2.77, P < 0.05), and the Ss factor (F(7,119) = 9.69, P < 0.01). Subsequently Dunn’s test (Kirk, 1968) was applied to test the increase (d = +8.5) from the baseline (68.5) to the end of instruction means (77.0) which was significant (P c 0.01) as well as the decrease (d = -7.8, P -c 0.05) from the end of instruction to the turn-off (69.2), and the decrease (d = - 12.7, P < 0.01) to 4 min after turn-off (64.3). The sharp drop in HR shown in Fig. 1 seems to be a genuine effect not unduly influenced by the small number of Ss. Blood pressure
The results for both SBP and DBP are shown in Fig. 3. SBP. The mean pressure during Bl was 110.7 mmHg and this increased to 119.5 at the end of
the instruction period. In the test period there was a further increase to 127.4 (after 4 min) and then the curve started to drop, reaching its lowest point 100, at the end of this phase. During the B2 there was an increase but the mean (104.9) did not reach the level of Bl. The systolic BP data were then analyzed in the same way as for HR rate (see Fig. 4), yielding significant F-values for both the time (F(7,119) = 5.98, P < 0.01) and the Ss factor (F(7, 119) = 10.10, P < 0.01). The subsequent Dunn’s tests also showed that the increase (d = +8.8) from the baseline mean (110.7) to the end of instruction phase (119.5) was significant (P < 0.01) as well as the decrease (d = -9.5, P < 0.01) to the time of turn-off, and the decrease (d = - 17.0, P < 0.01) to 4 min after turn-off. DBP. The assessment showed a very stable Bl (see Fig. 3) with a mean of 67.9 mmHg, while the instruction about the coming test yeilded an increase to 75.4. Contrary to the SBP there was no further increase at the beginning of the test phase. Instead the DBP mean started to drop immediately and reached the level of 57.0 at the end of this phase. During B2 there was, also in contrast with the SBP, a continuous increase of the curve and the mean of this phase (68.4) corresponded closely with that of Bl. The statistical analysis of the DBP data (see Fig. 5) yielded a significant time factor (F(7,119) = 2.73, P < 0.05) as well as Ss factor (F(7,119) = 6.98, P < 0.01). The following comparison between means showed that the increase (d = +7.6) between baseline (X = 67.9) and end of instruction (2 = 75.5) was significant (P < O.Ol), as was the decrease (d = - 10.0, P < 0.01) to 4 min after turn-off (X = 65.4). The decrease (d = -4.8) from the end of instruction to the point of turn-off was, however, not significant. The data for both BPS show that the group of patients displayed a significant increase followed by a significant decrease which reached its peak value 4min after the film had been turned off.
Phys~ologicai responses in blood phobics
t409 \ I 30
izo“\I I IO too
BO4-a ‘t ?O-
‘0 P-” ’ .o’
At the turn- off
I MBose llne
after turn - off
Fig. 6. HR and BP for Patient 1 during the different
Fig. 5. Mean DBP during consecutive phases of the test.
Periods of the test.
in order to further test the generality of these patterns of change between the phases, X%ests for the number of Ss changing, were computed (see Table 1). For HR a criterion of t_ 1 bpm, and for BP +2 mmHg was applied. For all three measures a significant proportion of the patients increased their values from the baseline to the instruction phase, and decreased their values from the instruction to the 4min after turn-off phase. The number of patients showing a decrease between the instruction and turn-off phase was, however, not significant. Some indiuidual data
In order to further illustrate the cardiovascular responses of blood phobics some indi~dual data will be presented. The data of those 5 patients who showed the strongest behavioral reactions, i.e. either fainted or were on the edge of fainting, were picked out without knowledge of their physiological reactions. Patient I. A 29-yr-old male, who had been blood phobic for as long as he could remember, and had fainted on many occasions. This patient’s HR (see Fig. 6) displayed a fairly stable baseline with a mean of 86.4 bpm. At the start of the instruction phase there was an increase of about 10 bpm, and during the test period his HR first increased to ‘103 bpm and then rapidly dropped to 42 bpm when the film was turned off. The first minute after turn-off his HR was down to 28 bpm and then it gradually increased to a maximum value of 81 bpm at the end of B2. When this patient’s data were replayed through a polygraph, q scrutiny of the write-out showed that he had 33 periods of asystole, varying between 2-9 set in length, during a 7-min interval (from 1 min after the start of to film to 3 min after turn-off). Table
Basehne-instr. Measure HR x2 SBP
2 DBP %? 1. Decrease:
= t ~-0 0 14 27.98. P < 0.001 I 0 13 22.41, P < 0.001 I 2 11 12.99. P < 0.01 = .
Instr.-turn-off’ -1 = 8 3.55 6 2.29 7 2.71
of the test Instr.-4 =
13 1 0 22.41, P < 0.001 11 2 1 12.99, P < 0.001 11 1 2 12.99, P < 0.01
:IQ ,I j, , >I “, 0
Fig. 7. HR and BP for Patient 2 during periods of the test.
Fig. 8. HR and BP for Patient 3 during periods of the test.
The patient showed similar, but not quite that dramatic BP reactions. His SBP was rather variable (140-123) with a mean of 130.0 mmHg during Bl. There was a slight increase (136) in the instruction phase, and this continued at the start of the test period (144). Then followed a marked drop in BP and the lowest value 108 was reached 4 min after turn-off. His DBP showed a similar picture, but here the BP during B2 did reach that of Bl, which was not the case for SBP. Patient 2. A 33-yr-old male, who became aware of his blood phobia when doing military service some 13 yr previously. He had never fainted in the phobic situation. This patient (see Fig. 7) also had a stable HR (X = 63.4 bpm) during Bl. Nothing happened during the instruction phase and for the first 8 min of the test period. Then there was a sudden drop from 60 bpm to 42, 38 and 31 just before he turned the film off. This patient also had nine periods (3-6 set) of asystole during a 2.3-min interval before turning the film off. However, he ‘recovered’ quickly and was back at the Bl values 5 min later. This patient’s BP varied a bit during Bl, and nothing happened during the instruction phase. In the test phase the SBP started to drop after 7-8 min and reached its lowest value (90) at the turn-off. Diastolically there was a more gradual decrease from a mean of 64.7 mmHg during Bl to 45 at the end of the test phase. During B2 both BP measures increased gradually but only DBP reached ‘the initial level. Patient 3. A 28-yr-old male, who first noticed his phobia when he fainted while undergoing dental surgery at the age of 15. Since then he had fainted on five occasions. This patient (see Fig. 8) managed to watch the film for almost 20 min before fainting. Both his HR and BP showed some variability during Bl . Nothing remarkable happened during the instruction phase and the start of the test phase, except a slow and gradual decrease in SBP. However, after 17 min of watching the film his HR rapidly dropped 30 beats (from 78 to 48) and remained at that level until the patient turned the film off. During the first minute after turn-off he had two 5-set periods of asystole. His SBP had decreased from a mean baseline value of 128.8 mmHg to 108 at turn-off, but immediately afterwards dropped to 86 and then started rising again. DBP showed a similar gradual decrease from a mean of 77.8 mmHg during B2 to 60 at turn-off, dropped further down to 40 immediately afterwards and then rose gradually back to its initial level. Patient 4. A 44-yr-old male, who fainted when cutting his finger at the age of 9. After that he had fainted about five times. This patient (see Fig. 9) displayed an unusually low (3 = 55.8 bpm) and fairly unstable baseline HR. There was an increase at the start of the instruction phase, but no change during the test period. Two minutes after turn-off there was a drop to 48 bpm, with three periods (3-6 set) of asystole, and then a gradual increase. His BP reactions were, however, very strong. After a mean of 122.8 mmHg during Bl, the instruction phase caused an increase to 131, and the test period a drop to 95. This decrease
responses in blood phobics 61
40 I 20
and BP for Patient 4 duringthe different periods of the test.
Fig. 10. HR
and BP for Patient 5 during the different periods of the test.
continued and reached its peak of 83,4 min after turn-off, whereafter there was a gradual recovery. DBP showed very much the same picture; a mean baseline value of 70.3 mmHg, 71 during the instruction phase, a sharp drop to 50 at turn-off and a further substantial drop to 30, 2 min after turn-off. Then followed a rise and at the end of B2 the BP was almost up to the initial level. Patient 5. A 35-yr-old male, who had been phobic since the age of 7 when he watched a violent film, Since then he had fainted about 10 times in the phobic situation. This patient (see Fig. 10) had a rather stable HR (51= 77.2) during Bl. This increased markedly during the instruction phase (94 at its end), and continued rising during the test period, with a peak of 111 after 4 min of watching the film. Then it dropped to 86 at turn-off, and 70 during the 6th mm after turn-off, but it never reached an unusually low level. This patient had only one 5-set period of asystole during the 3rd min after turn-off. The BP reactions were, however, much more pronounced. After a mean SBP of 134.8 mmHg during Bl there was an increase to 153 during the instruction phase and to 156 at the first measurement of the test period. Then it started dropping; to 126 at turn-off and to 90, 4 min. later. After that it was a clear recovery almost back to the initial level. The DBP showed a similar picture. The baseline mean was 71.7 mmHg, and there was a small rise at the instruction phase. During the test period it dropped to 59 at turn-off, and continued down to 45, 4min afterwards. Then the DBP recovered and ended somewhat higher than the Bl mean. DISCUSSION
The results of the present study corroborate the hypothesis under investigation, i.e. blood phobics display a diphasic response when confronted with their phobic stimuli. The first phase is similar to that displayed by other phobics, an increase in HR and BP. Then, instead of a gradual decrease and return to baseline level as exposure to the phobic stimuli continuous (Marks, 1981), the blood phobics show a sharp decrease below baseline in both HR and BP, and this leads to fainting if it is not possible to leave the situation. The bradycardia and drop in BP varies in magnitude, but seem to be very pronouned in those patients who faint or are close to do so. The 5 patients with fainting reactions all displayed either bradycardia or sharp drops in BP.
LARS-G&AN bsr et al.
Furthermore, all had at least one period of asystole of 5 set length while watching the film or soon after turning it off. How frequent this response pattern is in blood phobics cannot be completely answered by the present study. This is due to the design of the test where the patients were allowed to ‘escape’ by terminating the showing of the film. This route was chosen by 14 of the 18 patients and as many as 6 had turned it off before 1 min had elapsed, and 9 before 2 min of watching. Those who showed fainting behavior watched the film between 1.45-19.75 min. It is probable that many of those that turned the film off before 2 min would have displayed fainting behavior, bradycardia and/or BP decrease, had they only dared to watch the film longer, at least if judging from their explanations to the ‘premature’ escapes. The X2-tests of the number of patients changing between the phases in a manner predicted by the two-phase hypothesis did, however, show that the response pattern was very common. Different hypotheses to explain the physiological reactions of blood phobics have been proposed. Graham et ai. (1961) suggested that during the first phase of the diphasic response there is a massive sympathetic arousai which is to some degree baianced by parasympathetic activity. Then this homeostasis ceases abruptly (when the person has reached the point of ‘no return’ and need not be anxious any more), leaving the parasympathetic activity unopposed which eventually leads to fainting. This hypothesis cannot, however, account for those cases where fainting occurs without the prior sympathetic arousal (cf. patient 3). Engel (1962) assumed an initial redist~bution of blood to the extremities, which is considered an innate response to threat preparing the individual for action. If this is impossible venous return to the heart is reduced and fainting follows when the BP has reached a low enough level. Engel (1978) has also proposed that situations known to cause fainting are characterized by simultaneous activation of the sympathetic and parasympathetic systems. This proposal is very similar to that of Graham et al. (1961). Carruthers and Taggart (1973) emphasized the parasympathetic system in explaining this response, but this explanation has been questioned as atropine injection (Johnstone, 1976) was unsuccessful in reversing the fainting response. Edmondson et al. (1978) used the proposal of Glick and Yu (1963) when explaining the vasovagal episodes in dental-surgery patients. Due to apprehension or anxiety there is an acute rise in BP which stimulates the vasoreceptors of the carotid sinuses and the aortic arch. As a consequence, there is a generalized inhibition of sympathetic tone, which results in bradycardia and arteriolar dilatation. These changes produce a decrease in cardiac output, hypotension and reduced total peripheral resistance. In summary, there is a generalized inhibition of sympathetic tone with a relative increase in vagal activity. There is thus a clear lack of agreement between different hypotheses purporting to explain the unique physiologicai response pattern of blood phobics, and further research on autonomic activity while confronting phobic stimuli is clearly needed. The present study has established a diphasic response pattern in clinical patients with blood phobia, but did not have the aim to test different hypotheses in this area. Future research into the physiological responses of blood phobics should include skin conductance, finger temperature and blood flow, since peripheral resistance has been reported to decrease (Glick and Yu, 1963) and vascular resistance to increase (Kozak and Montgomery, 1981). Another issue of importance is whether the specific physiological response pattern displayed by the blood phobics is stimulus elicited or individually bound. In other words, would non-blood-phobic persons show similar but reduced reactions to blood stimuli, i.e. are the blood phobics merely displaying extreme reactivity but in the same direction as ‘normal’ persons? Or are these response characteristic for blood phobics only, and if so, are they displayed by blood phobics in ‘ordinary’ stress situations as well. This question is currently being investigated in our laboratory. Adcnowledgements-We gratefully acknowledge the assistance from Dr Torkel /&erg who lent us the film of thoracic operations, and Jan Johansson who assisted in the computerized data analysis. Professor Ame Cihman made valuable comments on an early draft of the manuscript. This research was partly supported by a grant (05452) from the Swedish Medical Research Council.
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