No abstract

Background: Sympathetic blocks (SBs) have been used widely to relieve the symptoms of sympathetically maintained pain (SMP). The thoracic sympathetic ganglion is not separated from somatic nerves by muscles and connective tissue. The upper thoracic ganglion runs along the posterior surface of the vertebral column in close proximity to the adjacent epidural region. This anatomical difference leads to frequent epidural and intercostal spread in cases of thoracic SBs. The purpose of this study was to investigate the incidence of inadvertent intercostal and epidural injections during thoracic SBs.Methods: Twenty-two patients who were suffering from complex regional pain syndrome or lymphedema after breast cancer surgery were managed with two or three times of thoracic SBs. Therefore, injections of 63 thoracic SBs from 22 patients were enrolled in this study. An investigator who did not attend the procedure evaluated the occurrence of intercostal or epidural spread using anteroposterior fluoroscopic images.Results: The overall incidence of inadvertent intercostal or epidural spread of contrast was 47.5%. Among the inadvertent injections, intercostal spread (34.9%) was more frequent than epidural spread (12.6%). Only 52.5% of the thoracic SBs demonstrated successful contrast spread without any inadvertent spread. The mean difference in skin temperature between the blocked and unblocked sides was 2.5 ± 1.8ºC. Fifty-nine (93.6%) injections demonstrated more than 1.5ºC difference.Conclusions: Thoracic SBs showed a high incidence (47.5%) of inadvertent epidural or intercostal injection. Thus, special attention is required for the diagnosis of SMP or the injection of any neurolytic agent around sympathetic ganglion.

Background: Robot-assisted laparoscopic radical prostatectomy is an advanced and popular surgical technique. However, increased intracranial pressure which is caused by CO2 pneumoperitoneum and Trendelenburg position is the main cerebrovascular effect. Measurement of optic nerve sheath diameter using ocular ultrasound is a noninvasive and reliable method for the assessment of intracranial pressure. The primary endpoint of this study was to identify whether low blood pressure regulation has any benefit in attenuating an increase of optic nerve sheath diameter during robot-assisted laparoscopic radical prostatectomy.Methods: Optic nerve sheath diameter and cerebral oxygen saturation were measured at baseline (supine position), one and two hours after pneumoperitoneum and Trendelenburg position respectively, and after return to supine position in normal (n = 27) and low blood pressure groups (n = 24).Results: Mean optic nerve sheath diameter values measured at one and two hours after pneumoperitoneum and Trendelenburg position were significantly increased compared to the baseline value (P < 0.001 in normal blood pressure group; P = 0.003 in low blood pressure group). However, the mean optic nerve sheath diameter and cerebral oxygen saturation measured at any of the time points as well as degrees of change between the two groups did not show any significant changes. The peak values of optic nerve sheath diameter in normal and low blood pressure groups demonstrated 14.9% and 9.2% increases, respectively.Conclusions: Low blood pressure group demonstrated an effect in maintaining an increase of optic nerve sheath diameter less than 10% during CO2 pneumoperitoneum and Trendelenburg position.