Comparison of the acoustic windows for the thoracic paramedian epidural approach after shoulder rotation: The lateral decubitus versus the sitting position.

BACKGROUND: The aim of this study was to compare the mean lengths of the posterior longitudinal ligament (PLL) as the acoustic window during the thoracic paramedian epidural approach after shoulder rotation, while subjects were in the lateral decubitus or in the sitting position. METHODS: Thirty-two adult male volunteers were placed in the right decubitus position or sitting position on a horizontal operating table. To obtain an optimal ultrasound view for the PLL on the right side, thoracic spinal ultrasonography was performed at the T6/7 interspace using the paramedian oblique sagittal plane. PLL length was measured on the ultrasound image before and after right shoulder rotation. RESULTS: Before shoulder rotation, the difference in mean PLL length between the sitting (11.1±1.3mm) and lateral decubitus (10.7±1.2mm) positions was not statistically significant (P=0.05). Within-position, the before and after comparison revealed that after shoulder rotation, PLL length was significantly increased to 12.2±1.4mm (P<0.001) and 12.0±1.5mm (P<0.001) in the sitting and lateral decubitus positions, respectively. However, after shoulder rotation the between-position difference in mean PLL length was not statistically significant (P=0.50) CONCLUSIONS: Shoulder rotation did not result in a statistically significant difference in the dimension of the acoustic target window for paramedian thoracic epidural access in the sitting compared to the lateral decubitus position.

Haemodynamic changes and incisional bleeding after scalp infiltration of dexmedetomidine with lidocaine in neurosurgical patients.

BACKGROUND: The purpose of this randomised controlled study is to compare the haemodynamic changes and the degree of incisional bleeding after scalp infiltration of lidocaine and dexmedetomidine versus lidocaine and epinephrine for patients with hemi-facial spasm undergoing microvascular decompression. METHODS: Fifty-two patients were injected with 5 mL of 1% lidocaine with either dexmedetomidine (2 µg/mL) or epinephrine (1:100,000 dilution) to reduce scalp bleeding. Mean blood pressure and heart rate were recorded every minute for 15 minutes after scalp infiltration. The primary outcome was the incidence of predefined hypotension, which was treated with administration of 4 mg ephedrine as often as needed. The number of administrations and total amount of ephedrine administered were also recorded as a measure of the severity of hypotension. The neurosurgeon scored incisional bleeding by numeric rating scale from 0 (worst) to 10 (best). RESULTS: The incidence of hypotension (68% vs. 34.8%, P = 0.02) and the frequency (P = 0.02) and total dose (P = 0.03) of ephedrine administered were lower in the dexmedetomidine group than in the epinephrine group. In addition, there was no difference in mean blood pressure between the two groups but heart rates were lower in the dexmedetomidine group (P = 0.01). Incisional site bleeding was better with epinephrine (median [interquartile range] of the numeric rating Score: 6 [4] in the dexmedetomidine group and 8 [2] in the epinephrine group; P < 0.001). CONCLUSION: The dexmedetomidine-lidocaine combination may be recommended as a substitute for epinephrine-lidocaine for scalp infiltration in neurosurgical patients, especially neurologically compromised patients.

Relationship between first dorsal sacral foramen and lumbar facet joint connecting line in South Korea populations: Retrospective study.

The first sacral nerve root block (S1 nerve root block) is a practical procedure for patients with radiating lower back pain. In general, S1 nerve root block is performed under x-ray fluoroscopy. It is necessary to adjust the position of the patient and angle of fluoroscopy to properly visualize the first dorsal sacral foramen (dorsal S1 foramen). The purpose of this study was to analyze the location of dorsal S1 foramen and lumbar facet joint in S1 nerve root block.A total of 388 patients undergoing x-ray fluoroscopy-guided S1 nerve root block in the prone position were examined. X-ray fluoroscopy was fixed at the corresponding location of facet joint of L4-5 and L5-S1. The relationship of the connecting line vertical to L5-S1 facet joint and upper margin sacrum was evaluated. The surface anatomical relationships between dorsal S1 foramen and lumbar facet joint were assessed.Based on the localization of dorsal S1 foramen, the line drawn from point to upper margin sacrum passed through the dorsal S1 foramen in all cases. The horizontal distance from the spinous process to the dorsal S1 foramen was 25.9 ±â€Š3.0 mm for men and 26.2 ±â€Š1.4 mm for women. The horizontal distance from the between posterior superioriliac spine to the dorsal S1 foramen was 26.2 ±â€Š2.7 mm for men and 26.8 ±â€Š1.7 mm for women. The vertical distance from the upper margin of sacrum to dorsal S1 foramen to the dorsal S1 foramen was 45.6 ±â€Š6.5 mm for men and 43.8 ±â€Š6.0 mm for women.The connecting line vertical to L5-S1 facet joint and upper margin sacrum is located on the same line from the dorsal S1 foramen. For difficult cases of locating dorsal S1 foramen, the lumbar facet joint can assist in predicting the vertical location of the dorsal S1 foramen.