Chia-Sheng Chang

Intravenous mannitol does not increase blood-brain barrier permeability to inert dyes in the adult rat forebrain.

Intravenous mannitol (IV-M) is widely administered in the clinic to lower intracranial pressure in patients with brain trauma and stroke. However, intracarotid arterial mannitol (ICA-M) is known to potently open the blood–brain barrier (BBB) to serum protein tracers such as the Evans blue dye (EBD). In this study, we aimed to determine the potential effect of IV-M on BBB permeability to EBD and a small molecular tracer sodium fluorescein dye (NaF). Rats received intravenous EBD/NaF injections, and after a 30-min equilibration time, they received mannitol (20%, 0.5 g/kg) through either route of administration. At 90 min after the mannitol injection, the rats were perfused to rid their circulations of the tracers, and the tracers extravasated into the brain parenchyma were measured by photospectrometry. As expected, ICA-M considerably increased EBD extravasation into the rat forebrain regions, including the motor cortex (P=0.0069), the striatum (P=0.0097), and the hippocampus (P=0.0281; student’s t-test). In marked contrast, IV-M exerted no effect on EBD extravasation into these forebrain regions. To increase the power of the IV-M study, we repeated the experiments in two independent trials of experiments (n=6–9/group/trial) and found the same result. Finally, consistent with no effect on EBD extravasation, IV-M had no effect on NaF extravasation into the rat forebrain. In conclusion, we report direct evidence that IV-M, at a dose used clinically, in contrast to the same dose of ICA-M, exerted no effect on BBB permeability to protein and small molecular tracers.

Increase in Evans blue dye extravasation into the brain in the late developmental stage.

The development of the blood–brain barrier (BBB) against permeability to inert tracers, such as Evans blue dye (EBD), occurs quite early on at embryonic stages (before E13–E15), and the BBB remains resistant to EBD between E15 and early adulthood (P20–P30). Here, we aimed to examine the changes in EBD permeability at a later stage in development, specifically comparing young rats (P20) with adult rats (P86). We found markedly higher EBD extravasation into the forebrains of adult rats compared with those of the young rats (P=0.0132; Student’s t-test). In contrast, there was no difference in EBD extravasation to the liver, suggesting no change in vascular permeability in peripheral tissues. Furthermore, EBD extravasation into the cerebellum was less prominent than that into the forebrain, suggesting that the disruption of the BBB was brain-region specific. In conclusion, we found a specific increase in EBD extravasation in the mature forebrain, and the protocol that we used may be a good template for studying developmental disruption of the BBB.

Detection of Right Heart Emboli by Transesophageal Echocardiography in Cement Implantation Syndrome in an Elderly Patient

SUMMARY Femoral fractures are common and lethal among elderly patients. The elderly suffer more perioperative risks because of their complicated medical conditions and poor physical reserves. During cemented arthroplasty surgery in the elderly, unstable hemodynamic changes are frequently noted when the cement and prosthesis are inserted. Transesophageal echocardiography (TEE) allows rapid perioperative diagnosis and management of hemodynamic changes. We report an elderly patient with paroxysmal atrial fibrillation, in whom a huge ser- pentine embolus was noted by TEE. Although cardiovascular collapse was encountered during cemented hip arthroplasty surgery, the patient was successfully resuscitated and the related perioperative risk was managed by TEE application. (International Journal of Gerontology 2008; 2(3): 115-119)

Knotting of a Pulmonary Artery Catheter in the Superior Vena Cava

Catheter knotting is a rare but severe complication of pulmonary artery catheterization. We present a case in which knotting of the pulmonary artery catheter occurred during tricuspid valve repair in a 29-year-old man. We attempted to uncoil the knot with a guidewire under fluoroscopy, but final successful removal of the knot in the pulmonary artery catheter required surgical intervention. Related instances in the literature are reviewed, and appropriate management and prevention strategies are discussed.

Can Qi Gong Produce Immediate Pain-Relieving Effect in Pain Treatment?

The patients in pain have received Qi-Gong treatment in the Pain Clinic for 15 to 20 minutes. The pain-relieving effect was evaluated by Visual Analogue Scale (VAS). The results show Qi-Gong can change patients pain intensity from moderate to mild pain after treatment. The incidence of feeling Qi during treatment is 57.1% and 42.9% felt no Qi.. The incidence of side effects including one dizziness and one headache is 4.8%. This study proves Qi-Gong treatment is effective in pain treatment.

Down Regulation of C-Fos and C-Jun Expressions in Chronic Meperidine-Treated Patients

Objectives. Meperidine is one of the most widely used analgesics in clinical practice. Previous data suggested that chronic administration of opioids might lead to long-lasting adaptations on neuronal circuits in the brain. c-fos and c-jun are induced rapidly but transiently in certain brain regions by acute administration of opiates. Chronic exposure may desensitize the ability of the seproteins to be induced. The purpose of this study was to investigate c-fos and c-jun expressions in peripheral blood lymphocytes in patients with chronic exposure to meperidine. Methods. The exposure group comprised 5 patients who received meperidine for at least 6 months. We selected 12 healthy adult volunteers with no medical history of opiate administration as the control group. Peripheral blood was drawn by venipuncture. Total RNA was isolated and reverse transcription was performed. Quantitative competitive PCR was performed to quantify the human c-fos and c-jun. All statistical data were expressed as mean SEM. Results. The c-fos level in the peripheral blood of the patients who underwent prolonged meperidine treatment was much lower than that of healthy individuals who had not been exposed to meperidine. While the c-fos level of healthy individuals decreased with time after phytoagglutinin (PHA) treatment, it did not change in those chronically exposed to meperidine. Conclusions. Chronic exposure to meperidine desensitized c-fos and c-jun expression in the peripheral blood lymphocytes of patients with chronic exposure to meperidine.

Evaluation of a Partial CO2 Re-breathing Fick Technique for Non-invasive Measurement of Cardiac Output in SICU Patients

To evaluate the reliability of a new non-invasive method of cardiac output measurement (NICO) based on partial re-breathing and a differential form of the CO2 Fick equation; we compared it with the currently accepted technique of thermodilution (TDCO) method in SICU patients. Simultaneous C.O. measurements by TDCO and NICO were performed in 50 mechanically ventilated patients. A combined flow/CO2 sensor and a computer controlled re-breathing valve were placed between the ET tube of the patient and Y piece of the breathing circuit. The sensors and valving were connected to a non-invasive C.O. monitor, which performed the data acquisition, valve control and calculation and display of cardiac output. Bolus thermodilution is measured as the standard procedure. Paired t test and Correlation statistics are used to compare the degree of agreement between concurrent measurements of TDCO and NICO. A total of 150 triplicates, simultaneous C.O. measurements were carried out with TDCO and NICO. Linear regression analysis showed good correlation of TDCO and NICO in the critically ill patients (r2 ＞ 0.9). However, significant statistic differences between TDCO (5.6 ± 2.7 L/min) and NICO (6.0 ± 3.2 L/min) were seen with the paired t test (p = 2.77E-11). Bias and precision calculated for the NICO vs. TDCO collectively averaged 0.42 ± 0.72 L/min (95% CI = 0.12). In the critically ill patient, there was adequate correlation between NICO and TDCO to eliminate the need for PA catheterization. However, NICO is not an absolute C.O. value replacement of TDCO.