How Safe Is the Use of Intrathecal Vancomycin?

BACKGROUND: Central nervous system infection after neurosurgical procedures is a severe complication with high morbidity rates and sometimes mortality. Our experimental study aimed to investigate the biochemical and histopathologic effects of vancomycin on neural tissues when applied to the cisterna magna. METHODS: Wistar albino rats were randomly divided into 4 groups: Control (Group 1) and different vancomycin dose groups (Groups 2, 3, and 4). In Group 1, 0.1 mL cerebrospinal fluid was drained from the cisterna magna and 0.1 mL 0.9% NaCI (normal saline) was administered into the subarachnoid space. In the study groups, 0.1 mL cerebrospinal fluid was drained from the cisterna magna and 0.1 mg/200g rat per day (Group 2), 0.2 mg/200g rat per day (Group 3), and 0.4 mg/200g rat per day (Group 4) vancomycin were administered into the subarachnoid space for 7 days. All rats were sacrificed on the eighth day. Serum superoxide dismutase and catalase levels were measured. Histopathologic and immunohistochemical analyses were conducted. RESULTS: The findings showed that the administration of 0.2 and 0.4 mg/kg doses had significant differences in superoxide dismutase and catalase activity compared with the controls (P < 0.05). These vancomycin doses also induced the apoptotic process, and the enzyme activity results correlated with immunohistochemical results. CONCLUSIONS: Dose-related neurotoxicity of intrathecal vancomycin was shown at the cellular level. The importance of dose regulation of intrathecal vancomycin has come into view. To our knowledge, this is the first study in the literature that has investigated the neurotoxic effects of vancomycin.

Does Decompressive Duraplasty Have a Neuroprotective Effect on Spinal Trauma?: An Experimental Study.

BACKGROUND: Spinal cord injury (SCI) may result in neuromotor, sensory, and autonomic function damages. Edema because of spinal cord trauma can reach serious dimensions. The aim of this study was to histologically evaluate the effects of duraplasty on neural tissues. METHODS: Twenty-eight Wistar rats were randomly divided into 4 experimental groups: group 1 received laminectomy without SCI (sham); group 2 received laminectomy and SCI with the weight drop method; group 3 received laminectomy, SCI, and duraplasty within the first 6-8 hours of SCI; and group 4 received laminectomy, SCI, and duraplasty after 24 hours of SCI. The neurologic functions of the rats were tested periodically. All animals were euthanized 28 days after the surgery. Histopathologic and immunohistochemical evaluations were performed, and Kruskal-Wallis tests were used for statistical comparison of data between the groups. RESULTS: There was no significant difference in the Tarlov examination scores from different time points between the groups. The number of neurons stained with nuclear factor kappa beta was higher in group 3 than groups 1 and 4. The number of neurons stained with terminal deoxynucleotidyl transferase dUTP nick-end labeling was higher in group 2 than group 3. CONCLUSIONS: Decompressive laminectomy is a procedure frequently used in spinal trauma surgery. However, it is often unclear whether the decompression is fully adequate. Our results will aid the development of further studies regarding the reliability of duraplasty in the treatment of SCI.

How Safe is the Use of Intrathecal Fluorescein? An Experimental Study.

AIM: To investigate the effects of fluorescein-sodium on neural tissues. MATERIAL AND METHODS: Twenty-one Wistar rats were randomly divided into three experimental groups: control (group 1) and fluorescein-sodium groups with different doses (groups 2 and 3). In the control group, craniectomy following with durotomy was performed with the help of a loupe microscope, and a dry sponge was overlayed to the brain tissue. In the study groups, the open dura was covered with a sponge soaked with 0.02 mg (group 2) and with 0.2 mg (group 3) fluorescein sodium following craniectomy. Three weeks postoperatively, rats were sacrificed for the histopathologic evaluations. RESULTS: Fluorescein-induced apoptosis occurs in a dose-dependent manner in rats' neurons. It was determined that neuron and neuroglial cell TUNEL staining was statistically different among the three groups (p < 0.001). Our results indicated that fluorescein induces apoptosis, resulting in increased nuclear factor kappa beta (NF-kß) expression in a dose-dependent manner. CONCLUSION: Fluorescein sodium is used frequently during surgery for CSF fistulas. However, information in the literature about its safety is insufficient. Our study holds promise for the development of new studies on the reliability of this agent.

Does clinically measured ankle plantar flexor muscle strength or weakness correlate with walking performance in healthy individuals?

OBJECTIVE: Muscle strength is usually measured using isometric hand-held dynamometers (HHDs) in the clinic. However, during functional activities, the muscle acts more dynamically. The aim of this study was to investigate the relation between clinically measured plantar flexor (PF) muscle strength (PFMS) and laboratory measurements of peak ankle plantar flexion power generation (APFPG), peak ankle moment (PAM), peak plantar flexion velocity (PFV) and mean gait velocity in healthy participants. METHODS: The maximum PFMS on non-dominant sides in 18 able-bodied persons 23.88 (SD 3.55 years) was measured before (Pre-S) and after a stretching (Post-S) procedure (135 sec. × 13 rep. with 5 sec. rest) by using a HHD. The stretching procedure was used to generate temporary PF muscle weakness. Gait analysis was carried out for Pre-S and Post-S conditions. Normalized (by weight and height) and non-normalized HHD scores and differences for both conditions were correlated by Pearson correlation coefficient calculations (p< 0.05). RESULTS: Reduced PFMS (%23, p< 0.001) in Post-S, according to the HHD scores, has only a weak correlation with APFPG (r> 0.3, p< 0.5). Gait velocity was found to be strongly correlated with APFPG only in the Post-S condition (r= 0.68, p< 0.002). HHD scores and PAM were moderately correlated with the non-normalized Post-S condition (r= 0.44, p= 0.70) and strongly correlated with the non-normalized Pre-S condition (r= 0.62, p< 0.01). DISCUSSION: HHD scores of plantar flexor muscles give very limited information about the PF performance during walking in healthy individuals. Simple normalization did not improve the relations. Clinically measured isometric muscle strength and muscle weakness have only moderate strengths for establishing a treatment protocol and for predicting performance during walking in neurologically intact individuals.

The effect of 25-hydroxyvitamin D levels on QT interval duration and dispersion in type 2 diabetic patients.

AIM: To assess the relationship between corrected QT (QTc) interval and vitamin 25-hydroxyvitamin D levels (25-OHD) deficiency in type 2 diabetic patients. METHODS: The study included 253 patients with type 2 diabetes and 170 age-matched controls treated between October and December 2013. QTc duration and QTc dispersion were measured on ECG recordings and 25-OHD, calcium, phosphorus, and blood glucose levels were determined. RESULTS: Patients with diabetes had significantly longer QTc duration and QTc dispersion than controls (P<0.001 and P<0.001 respectively). Diabetic patients with prolonged QTc duration were older and had longer diabetes duration and higher HbA1c levels than patients with normal QTc interval. They significantly more frequently had 25-OHD deficiency (P<0.001), but had similar calcium and phosphorus levels. Diabetic patients with prolonged QTc dispersion were of similar age and had similar diabetes duration and HbA1c levels as patients with normal QTc dispersion. They significantly more frequently had 25-OHD deficiency (P=0.010), but had similar calcium and phosphorus levels. CONCLUSION: This study showed prolonged QTc duration and QTc dispersion in patients with type 2 diabetes, especially those with 25-OHD deficiency.