Inadvertent intrathecal administration of amidetrizoate. K. Nakazawa 2, M. Yoshinari 1, S. Kinefuchi I and K. Amaha 2 l Intensive Care Unit, Tohoku University ...
IntensiveCare Medicine
Intensive Care Med (1988) 15:55-57
© Springer-Verlag 1988
Inadvertent intrathecal administration of amidetrizoate K. Nakazawa 2, M. Yoshinari 1, S. Kinefuchi I and K. A m a h a 2 l Intensive Care Unit, Tohoku University Hospital, Sendai, and 2Department of Anaesthesiology, Tokyo Medical and Dental University, School of Medicine, Tokyo, Japan Received: 15 February 1988; accepted: 13 June 1988
Abstract. Two cases are presented in which amidetrizoate (Urografin ®) was accidentally introduced into the intrathecal cavity. Intrathecal lavage and continuous administration of thiopentone were very successful in preventing further systemic deterioration.
Key words: Intrathecal amidetrizoate - Convulsions - Intrathecal lavage
Amidetrizoate (Urografin®), a water soluble iodine containing ionic contrast medium, brings about direct injury to the central nervous system if it is administered intrathecally. Over the past 20 years there have been no reports of intrathecal amidetrizoate administration but, it is likely that this has occurred with some frequency. Recently we treated two patients who accidentally received an intrathecal injection of amidetrizoate during epidurography. In the following report we present these cases and discuss the available treatment.
Case reports Case one A 31-year-old m a n underwent epidurography with 76°7o Urografin ® for investigation of low back pain at a regional hospital. During the procedure approximately 5 ml of contrast m e d i u m was inadvertently introduced into the intrathecal cavity. Twenty minutes later, his arterial blood pressure dropped from 120/80 to 80/50 m m H g and he became cyanotic. Ninety minutes after the injection, he began to complain of uneasiness and he developed intermittent convulsions of the legs. They were accompanied by severe pain and progessively worsened. Four hours after receiving amidetrizoate, he was transferred to our hospital for intensive therapy. On admission to the ICU, he was comatose (Glasgow coma scale = 6). Repeated generalized convulsions were observed. Clinically, he was shocked with a blood pressure of 60/20 m m H g and a pulse rate of 150/rain. Arterial blood gas analysis breathing
r o o m air revealed a severe metabolic acidosis (pH 7.17, PaCO 2 = 21 m m H g , PaO 2 = 82.5 m m H g and base excess = - 2 0 . 1 mmol/1). A coagulation screen confirmed a diagnosis of Disseminated Intravascular Coagulation (DIC). He was intubated, and mechanically ventilated. Cardiovascular support was given with a continuous infusions of dopamine and noradrenaline. Diazepam was administered as intermittent intravenous boluses to treat seizures. A CT of the brain showed contrast m e d i u m extending up to cerebral ventricles and subarachnoid spaces. O n the third hospital day, the urinary output began to fall off and the serum potassium increased to critical levels in spite of diuretic therapy. Haemodialysis was initiated at this time, the total bilirubin, serum GOT and L D H values were elevated to 85.5 ~tmol/l 973 IU and 7650 IU, respectively. On the fifth day, he became increasingly hyperirritable and a continuous infusion of sodium tbiopentone ( 1 . 5 - 5.0 m g / k g / h ) was started. Five days later, he was no longer hyperirritable and a follow-up CT scan was normal. A n E C G showed a predominance of high voltage 6 waves. Voluntary movements of the arms and legs were abnormal. He was discharged from the ICU with incomplete recovery of CNS, renal and hepatic function on the 28th day, and needed haemodialysis for an further one month. Two m o n t h s after the discharge his renal and hepatic function returned to almost normal. His motor function h a d been recovered ten m o n t h s later.
Case t wo A 53-year-old m a n with low back pain was admitted to a regional hospital. Lumbar epidurography was performed with 76% amidetrizoate. Approximately 5 ml of the amidetrizoate was accidentally injected into the intrathecal cavity. Fifteen minutes later, he complained of severe pain in the left leg. Subsequently, he developed clonic convulsions of both legs. His neurological status progressively deteriorated and the convulsions became generalized. Four hours after the instillation, he was transferred to our I C U for further treatment. O n admission he was conscious but generalized convulsions were easily induced by any form of stimulation. His vital signs and cardiopulmonary function were normal. He received a continuous infusion of sodium thiopentone to control convulsions and was intubated and mechanical ventilated. Six hours after the injection of amidetrizoate, a brain CT scan revealed contrast medium extending up to the cerebral ventricles and subarachnoid spaces (Fig. 1). Intrathecal lavage was initiated to eliminate the contrast medium. Two spinal needles were inserted into the cervical and lumbar intrathecal spaces, and through these needles intrathecal lavage was performed
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K. Nakazawa et al.: Intrathecal amidetrizoate
Fig. 1. Cervical CT scan (a: above) and cerebral CT scan (b: below) before intrathecal lavage. Contrast medium is extending up to cerebral ventricles and subarachnoid spaces
Fig. 2. Cervical CT scan (a: above) and cerebral CT scan (b: below) soon after the intrathecal lavage. The contrast medium has disappeared from the subarachnoid space of cervical region. The remainder of contrast medium is significantly diminished
with warm sterile isotonic saline. Following the lavage, brain CT scan revealed that there was a significant reduction in the quantity of contrast medium in the subarachnoid spaces and cerebral ventricles (Fig. 2). Anticonvulcant therapy was continued as attempts to discontinue the sodium thiopentone infusion led to a recurrence of hypertonia and convulsions. Tendon reflexes were brisk, but gradually became normal. A repeat brain CT scan on the sixth day after admission was normal with no evidence of residual contrast medium. Anticonvulsant therapy was successfully discontinued. The patient was discharged from the ICU on the eight day with complete recovery.
Discussion T h e adverse effects o f i o d i n a t e d ionic contrast m e d i a o n the central nervous system m a y be e n o r m o u s because o f hyperosmotic effects a n d chemotoxicity [1]. There is the possibility that these contrast m e d i a are i n t r o d u c e d intrathecally by mistake. Turner [2] reported a case in which s o d i u m diatrizoate ( H y p a q u e ®) was administered intrathecally. The resulting severe
neurological c o m p l i c a t i o n s were a c c o m p a n i e d by acute renal failure. I n this case, the severe convulsions were controlled with c o n t i n u o u s sedation using intravenous amyl obarbitone, whilst renal f u n c t i o n progressively worsened. I n the first case, the p a t i e n t was hypotensive a n d h a d D I C o n a d m i s s i o n to our ICU. The D I C could have b e e n caused by the a n a p h y l a c t i c reaction due to iodine hypersensitivity b u t this c a n n o t be c o n c l u d e d with certainty, I n this case, i n a d e q u a t e p e r f u s i o n of the microvasculature a n d severe m e t a b o l i c acidosis (possibly due to u n c o n t r o l l e d seizures) m i g h t have played a significant role in the development of DIC. I n the second case, the p a t i e n t ' s general c o n d i t i o n was well preserved a p a r t from convulsions. The patient was kept tilted " h e a d up" until a d m i s s i o n to the I C U to c o n f i n e the contrast m e d i u m in the l u m bosacral region. We tried to eliminate intrathecal amidetrizoate as previously suggested by Grainger [3].
K. Nakazawa et al.: Intrathecal amidetrizoate T h e C S F c o n c e n t r a t i o n o f a m i d e t r i z o a t e decreased f r o m 24.5 m m o l / 1 to 3.7 retool/1 allowing i n t r a t h e c a l lavage. The b r a i n C T scans also d e m o n s t r a t e d a decrease in residual a m i d e t r i z o a t e . A t t e m p t s to discont i n u e a n t i c o n v u l s a n t led to a relapse o f h y p e r a c t i v i t y suggesting t h a t there m i g h t be reversible o r g a n i c changes in the central nervous system, or t h a t residual c o n t r a s t m e d i u m persistently s t i m u l a t e d the nervous system. We prefer to use a c o n t i n u o u s i n f u s i o n o f t h i o p e n t o n e as it provides a high degree o f s e d a t i o n a n d is h i g h l y effective as an a n t i c o n v u l s a n t . W h e n severe generalized c o n v u l s i o n s continue, a n increase in cerebral m e t a b o l i s m a n d a relatively i s c h a e m i c state m a y result at a s u b c e l l u l a r level [4]. T h i o p e n t o n e reduces cerebral m e t a b o l i c d e m a n d s a n d depresses s y n a p t i c t r a n s m i s s i o n a n d m u l t i n e u r o n a l networks, resulting in a r e d u c t i o n in h y p e r i r r i t a b l e states [5]. A n ticonvulsive t h e r a p y s h o u l d be c o n t i n u e d until b r a i n C T findings a n d deep t e n d o n reflexes b e c o m e n o r m a l . I n c o n c l u s i o n i o d i n e ionic c o n t r a s t m e d i a s h o u l d n o t be used when there is a risk o f a c c i d e n t a l i n t r a t h e c a l
57 injection. I f such accidents occur, a p p r o p r i a t e circulat o r y s u p p o r t , i n t r a t h e c a l lavage a n d a n t i c o n v u l s a n t t h e r a p y are crucial in the successful m a n a g e m e n t o f these patients.
References |. Velaj R, Drayer B, Albright R, Fram E (1985) Comparative neurotoxicity of angiographic contrast media. Neurology 35:1290 2. Turner OA, Fisher C J, Bernstein LL (1966) Intrathecal sodium diatrizoate. Neurology 16:230 3. Grainger RG (1965) Complication of cardiovascular radiologic investigations. Br J Radiol 38:201 4. SiesjO BK (1986) Cellular calcium metabolism, seizures, and ischemia. Mayo Clin Proc 61:299 5. Shapiro HM (1985) Barbiturate in brain ischaemia. Br J Anaesth 57:82 Dr. K. Nakazawa Department of Anaesthesiology Tokyo Medical and Dental University School of Medicine Tokyo 113 Japan
