Prophylactic Consecutive Administration of Haloperidol Can Reduce the Occurrence of Postoperative Delirium in Gastrointestinal Surgery Tetsuya Kaneko, Jianhui Cai, Takanori Ishikura, Makoto Kobayashi, Takuji Naka and Nobuaki Kaibara First Department of Surgery, Faculty of Medicine, Tottori University, Yonago 683-0826, JapanPostoperative delirium has in recent years been a common complication which can interfere with the recovery of patients after surgery. Unfortunately there is still no medical procedure available which can completely prevent the occurrence of postoperative delirium. Haloperidol is a psychopharmacological agent that has been used to treat the delirium and agitation, especially in geriatric patients. To assess the effectiveness and safety of the use of haloperidiol for the reduction of postoperative delirium, we performed a randomized, comparative clinical study in which 78 patients who underwent gastrointestinal surgery received either 5 mg of haloperidol intravenously postoperatively at 21:00 for 5 consecutive days, or normal saline with the same schedule. Postsurgical evaluation revealed the incidence of postoperative delirium to be only 10.5% (4 of 38 patients) in the group receiving haloperidol treatment, compared to 32.5% (13 of 40 patients) in the saline treatment group. No significant neuroleptic side effects were seen in any of the patients. These results suggest that daily postoperative administration of haloperidol can reduce the occurrence of postoperative delirium safely. Key words: haloperidol; postoperative delirium
Delirium, defined as an acute disorder of
surgery and anesthetic drugs and postoperative
cognition, wakefulness and attention, has been
factors (e.g., hypoxia, hypocarbia and sepsis).
recognized as a relatively common postopera-
Although preventative measures against post-
tive complication in the elderly for some time,
operative delirium have been applied at pre-
yet, to date, surprisingly little is known about
operative, intraoperative and postoperative
effective procedures to reduce its occurrence.
levels, there is still little definitive information
Postoperative delirium can result in increased
available on successful prevention of post-
morbidity, delayed functional recovery and
operative delirium. The first consideration in
prolonged hospital stay (Adams et al., 1986).
the management of delirium is to find and treat
Therefore, early diagnosis, assessment, prompt
any underlying organic cause of the presented
treatment and prevention of postoperative de-
state of confusion. When confusion is evident,
lirium are important objectives for improved
prompt treatment is mandatory. The first ther-
management of elderly surgical patients.
apy of choice for such cases is an antipsychotic
drug such as haloperidol, which does not pro-
explain the pathogenesis of postoperative de-
duce hypotension, aggravate diabetes, hepatic
lirium (Adams et al., 1986). The responsible
disease or renal disease nor does cause over-
causative factors proposed are preoperative
sedation. The successful use of haloperidol in
factors (e.g., aging, pathologic status in the
such cases makes it an interesting therapeutic
brain, polypharmacy and drug interactions,
candidate for testing in the prevention of post-
metabolic problems, depression, dementia and
operative delirium in surgical patients. So far,
anxiety), intraoperative factors such as type of
there has been no effective prevention of post-
Abbreviation: DSM, Diagnostic and Statistical Manual of Mental Disorders
Table 1. Demographic data of patients
operative delirium with therapy which places
and subjected to routine laboratory testing. Be-
emphasis on medication. We proposed, there-
fore entering the study, oral consent was requir-
fore, that prophylactic administration of halo-
ed from each patient. The consenting patients
peridol may have a potential application as a
were then randomized into 2 comparative study
preventative medication for postoperative delir-
treatment groups. The randomization was con-
ducted by way of a closed envelope system. Post-
The aim of the current study was to evaluate
operatively, one group received daily adminis-
the effect and safety of daily postoperative ad-
tration of haloperidol intravenously, while the
ministration of haloperidol as a preventative
other group was given normal saline. After the
measure against the development of postopera-
5th day of the postoperative study treatment, the
tive delirium, with special attention being paid
2 treatment groups were compared for the inci-
to the sleep-wakefulness rhythm, in patients
dence of development of postoperative delir-
undergoing gastrointestinal surgery. Study drug Subjects and Methods
Haloperidol (Serenase, Dainippon Pharmaceu-tical, Osaka, Japan) at a dose of 5 mg in 1.0 mL
Study design and subjects
was administered intravenously daily at 21:00
Ethical comittee approval was obtained before
from the 1st through the postoperative day.
commencement of this study. Eighty patients
This dose of haroperidol was considered ade-
who were scheduled for elective gastrointes-
quate for providing comparable sedation for the
tinal surgery and admitted to the High and In-
patients. An equal volume of normal saline for
tensive Care Unit at Tottori University Hospital
injection (0.9% NaCl,Otsuka Pharmaceutical,
1 or 2 weeks before the scheduled surgery,
Tokushima, Japan) was administered by the
between April 1995 and August 1998, compris-
same route and schedule as the comparative
ed the study population. After admission, the
group of patients not receiving haloperidol.
patients were interviewed, clinically examined
Table 2. The incidence of postoperative de- Study measurements and evaluation lirium in patients with haloperidol treatment and saline treatment
On the 5th day after surgery, postoperative datawere collected from the patients and their nurs-
ing charts regarding i) cognition, with particularattention to signs and symptoms of delirium, ii)
use of pain medication and iii) sleep pattern,
with special attention being paid to the sleep-
wakefulness rhythm. Psychotic diagnoses were
*P < 0.05 compared to the saline treament patients.
based on the Diagnostic and Statistical Manualof Mental Disorders (DSM) criteria, DSM-III-R(American Psychiatric Association, 1987).
eases, preoperative medications, duration of op-eration and anesthesia, conditions during anes-thesia as event of hypotension and hypoxemia,
Statistical methods
and intraoperative blood loss). The demo-
The chi-square test and unpaired student t-test
graphic data of the 78 evaluable patients are
were used for the statistical analyses of the
listed in Table 1, and there were no statistically
results, which are presented as mean ± SD. A P
significant demographic differences between
value of less than 0.05 was regarded as statis-
Postoperative delirium developed in 17 of
78 patients (21.8%). Postoperative deliriumbegan 2 to 4 days after surgery. Four of the 38
patients (10.5%) were clinically diagnosed ashaving postoperative delirium in the study
During the study, 80 patients scheduled for
group. On the other hand, there were only 13
gastrointestinal surgery were selected for ran-
out of 40 (32.5%) in the control group (Table
dom placing into the 2 treatment groups, 40 into
2). Intensity and duration of postoperative
the haloperidol treatment group and 40 into the
delirial symptoms in the control group were
saline control group. Two patients who had
severe and longer respectively than those in the
entered the Intensive Care Unit had to be ex-
study group. Several other factors (e.g., drugs
cluded before randomization into the study.
and method for postoperative pain control,
The 2 groups were comparable with respect to
hypoxia and infection) were examined and not
baseline criteria (e.g., age, sex, preexisting dis-
found to be associated with the occurrence of
Fig. 1. Comparison of postoperative sleeping times for saline treatment patients and haloperidol treatment patients during the day and night during the first 5 postoperative days. Values are expressed as mean ± SD. Fig. 2. Comparison of postoperative sleeping times for delirious and non-delirious patients during the day and night during the first 5 postoperative days. Values are expressed as mean ± SD. There are statistically significant differences in day and night sleeping times between the delirious and non-delirious group (P < 0.05).
postoperative delirium. The patients who dev-eloped postoperative delirium in the control
Discussion
group were administered haloperidol immedi-ately until the delirial symptoms disappeared.
Postoperative delirium and other organic men-
Furthermore, the patients who developed post-
tal syndromes have been frequent and problem-
operative delirium in the haloperidol group also
atic complications, often requiring aggressive
were administered more haloperidol and flunitra-
medical management. Notably cardiotomy and
zepam to control sleep-wakefulness rhythm.
organ transplantation have appeared to involve
Extrapyramidal side effects have not develop-
several additive risk factors for the occurrence
ed during the use of this protocol; however, one
of postoperative mental disorders. Postopera-
tive delirium has also been a common problem
developed transient tachycardia, but this did not
in the field of gastrointestinal surgery. Un-
substantially interfere with clinical manage-
familiar surroundings and a sense of alienation
ment. No other complications or side effects of
appear to be factors which make patients more
haloperidol use occurred with this protocol.
likely to develop postoperative delirium. We
Between the 2 groups, there was no consider-
recently reported that sleep deficiency is likely
able variability in the duration of sleep time in
to predispose elderly patients to postoperative
the day or night. As a result, the difference in
delirium and so techniques designed to prevent
the average and total time of sleep between the
sleep deprivation may be of considerable value
2 groups was not statistically significant (Fig.
in reducing the incidence of postoperative de-
1). The ratio of sleep time during the day and
night was lower during the use of haloperidol.
Haloperidol, a high-potency antipsychotic
In contrast, special attention was paid to the pa-
agent, is considered to be the drug of choice for
tients who had developed postoperative deliri-
rapid control of delirium in the critically ill pa-
um, and there was close correlation between the
tient. Unlike other neuroleptic agents, haloperi-
development of postoperative delirium and de-
privation of sleep rhythm, that is, a short sleep
dynamic and respiratory function and does not
period during the night and a long sleep period
aggravate other functions (Fish, 1991). For this
reason and because the number of elderly pa-
tients in the operative population who are at risk
livered by the intravenous route. The reason for
in developing postoperative delirium has been
this route of administration-related difference
increasing, we felt that haloperidol would be a
suitable candidate medication to test for preven-
The use of haloperidol in physically com-
promised patients with delirium is not entirely
guidelines for haloperidol use in the treatment
neuroleptic agent, haloperidol has increased
of acute delirium. The initial intravenous dose
potential to cause extrapyramidal side effect
of haloperidol prescribed for acute delirium
symptoms. These effects are not dose-related
varies with the degree of delirium from only
and are sudden in onset. Extrapyramidal symp-
0.5–2 mg for mild agitation, to 2–5 mg for mod-
toms are seldom observed with the use of halo-
erate agitation, to 10–20 mg for severe agitation
peridol administered by the intravenous route.
(Fish, 1991). On the other hand, Levenson (1995)
Craven (1990) first reported on the prophy-
reported a case of delirium following lung
lactic intravenous administration of a small
transplantation that required 2,842 mg of
dose of haloperidol 4 times daily, and demon-
haloperidol intravenously over 4 days. Though
strated its effectiveness and safety in the
the maximally tolerated total daily dosage of
management of postoperative delirium in lung
haloperidol has not been fully established, it has
transplant recipients. Although further system-
been reported to range from 100 mg to over 530
atic investigation is required to determine the
mg (Korp et al., 1985; Levenson, 1995; Kaneko
full potential of clinical effectiveness for halo-
et al., 1997) and to be as high as 975 mg
peridol administration in the prevention of pos-
(Levenson, 1995). One case has been reported
toperative delirium, we have not found any in-
in which the intravenous administration of 7.5
creased frequency of postoperative delirium.
mg of haloperidol appeared to cause cardiac
These preliminary findings suggest that this
arrest (Menza et al., 1987). Thus, for the cur-
study protocol of daily postoperative intra-
rent study, it was important to design a protocol
venous haloperidol administration may be both
of haloperidol dose and schedule that not only
an effective and a safe means of preventing the
was potentially therapeutically effective, but
occurrence of postoperative delirium in patients
also safe for use in our patient population. Our
undergoing gastrointestinal surgery, partic-
consideration on the safety of our haloperidol
ularly in elderly patients who are at a higher risk
administration protocol depended on several
of development of postoperative delirium.
factors, which included its limitations of use in
This prospective study is the first systematic
an intensive care setting, frequent reassessment
evaluation of the use of prophylactic adminis-
of the patients mental state and careful monitor-
tration of intravenous haloperidol to reduce the
occurrence of postoperative delirium. The
mechanism by which haloperidol reduces the
both oral and intramuscular administration,
occurrence of postoperative delirium is not
rapid control of acute delirium with extreme
clear. Some studies suggest that actions other
agitation is best accomplished with intravenous
than the blockade of central dopamine receptors
delivery. Moulaert (1989) recommended intra-
may be responsible for haloperidol’s calming
venous administration of haloperidol because
effect in patients with delirium (Korp et al.,
the absorption may be erratic when the drug is
1985; Tesar and Stern, 1988). It is also not
given by the intramuscular route. Moreover,
clearly understood why prophylactic adminis-
the pain of intramuscular injection may be add-
tration of haloperidol reduced the incidence of
ed to the patient’s confusion. Menza and col-
postoperative deliriums after gastrointestinal
leagues (1987) also recommended intravenous
surgery; we intend to perform further investi-
administration of haloperidol in the immuno-
gation of the optimization of dosage and timing
suppressed patient due to the lower frequency
of extrapyramidal side effects when it was de-
in guinea pig and rat liver microsomes. Biochem
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