A 39-year-old woman diagnosed with complex regional pain syndrome type I of the right upper extremity, with a previous history of two arthroscopic surgeries on that shoulder. The last surgery presented as a complication an infection caused by pseudomonas which was successfully treated. The patient complained of moderate to severe burning pain every day in her right upper extremity, which did not respond to conventional analgesic treatments. Associated with this she presented oedema, colour changes and trophic changes in this extremity. Apart from CRPS, the patient was in good general health, neurologically normal, without hypertension or diabetes.
It was decided to perform a stellate ganglion block, for which intravenous access was established and the patient was monitored with electrocardiogram, blood pressure and O2 saturation. The block was performed by paratracheal approach using a 3.5 cm long needle with 10 ml of procaine 1% without epinephrine; the cricoid cartilage was palpated to discern the C6 level. The transverse process of the sixth vertebra was palpated between the trachea and the carotid sheath. Prior to the injection, aspiration was performed in order to rule out puncture of any vascular structure; the aspiration was negative. After the block, the patient presented Horner's syndrome.
Five minutes after the block, the patient manifested malaise, dizziness and severe headache. The patient's blood pressure increased from 135/80 to 235/135 mmHg, with sinus tachycardia. The hypertension was relieved by administration of intravenous metoprolol in fractional doses, bringing the blood pressure down to 140/90 mmHg. After vital signs were restored to normal levels, the patient complained of dizziness and fatigue accompanied by headache and hiccups, for which she was hospitalised.
An ECG, neurological examination and a cranial CT scan were performed and revealed no abnormalities. Thyroid tests were also performed to exclude thyrotoxicosis, which were normal. A few days later the patient returned to the clinic and reported weakness and a 'back and forth movement of the head' which had no medical explanation. The 'movement' disappeared two months later without the need for medication.