OBJECTIVE: The study was aimed to investigate the effects of different levels of pressure and duration of carbon dioxide and saline in the neck of rabbits on metabolic, hemodynamic, serum sodium concentrations and hematocrit changes. METHOD: Twenty-one New Zealand rabbits were randomly divided into 7 groups according to the following pressure of CO2 or saline: 0 kPa, 0.67 kPa CO2, 1.33 kPa CO2, 2.00 kPa CO2, 0.67 kPa saline, 1.33 kPa saline, and 2.00 kPa saline. In order to make a space for the endoscopic thyroidectomy, we filled the neck of rabbits with carbon dioxide and saline. Arterial partial pressure of CO2 (PaCO2), pH, heart rate (HR), mean arterial pressure (MAP), central venous pressure (CVP), serum sodium concentration and hematocrit were measured at baseline, 45 min and 90 min after filling with gas or saline and 30 min post-filling. RESULT: Insufflation of CO2 at 0.67 kPa did not have any significant effect on the parameters, PaCO2 increased significantly 45 min and 90 min after insufflation of 1.33 kPa CO2 (P < 0.01). Marked changes in PaCO2, pH and CVP occurred 45 min and 90 min after insufflation of 2.00 kPa CO2 (P < 0.01), and the parameters did not return to baseline in 30 min after desufflation (P < 0.05). In animals receiving saline irrigation no significant changes occurred in PaCO2, pH and serum sodium concentrations at any time point. There was a tendency of decrease in HCT, but no statistically significant changes were found (P > 0.05). CVP increased significantly 90 min after saline irrigation at 1.33 kPa (P < 0.05). A significant increase in CVP occurred 45 min and 90 min after saline irrigation at 2.00 kPa (P < 0.05). No significant changes in HR and MAP occurred in all animals. CONCLUSION Filling with saline which does not cause hypercapnia, acidosis or dilutional hyponatremia can be used in endoscopic neck surgery to create and maintain a working space.
Animals ; Carbon Dioxide ; administration & dosage ; therapeutic use ; Endoscopy ; Insufflation ; Rabbits ; Sodium Chloride ; administration & dosage ; therapeutic use ; Thyroidectomy ; methods

Curcumin-ethyl-cellulose (EC) sustained-release composite particles were prepared by using supercritical CO2 anti-solvent technology. With drug loading and yield of inclusion complex as evaluation indexes, on the basis of single factor tests, orthogonal experimental design was used to optimize the preparation process of curcumin-EC sustained-release composite particles. The experiments such as drug loading, yield, particle size distribution, electron microscope analysis (SEM) , infrared spectrum (IR), differential scanning calorimetry (DSC) and in vitro dissolution were used to analyze the optimal process combination. The orthogonal experimental optimization process conditions were set as follows: crystallization temperature 45 degrees C, crystallization pressure 10 MPa, curcumin concentration 8 g x L(-1), solvent flow rate 0.9 mL x min(-1), and CO2 velocity 4 L x min(-1). Under the optimal conditions, the average drug loading and yield of curcumin-EC sustained-release composite particles were 33.01% and 83.97%, and the average particle size of the particles was 20.632 μm. IR and DSC analysis showed that curcumin might complex with EC. The experiments of in vitro dissolution showed that curcumin-EC composite particles had good sustained-release effect. Curcumin-EC sustained-release composite particles can be prepared by supercritical CO2 anti-solvent technology.
Carbon Dioxide ; chemistry ; Cellulose ; administration & dosage ; analogs & derivatives ; chemistry ; Curcumin ; administration & dosage ; chemistry ; Delayed-Action Preparations ; Solubility ; Solvents ; Technology, Pharmaceutical

OBJECTIVE: Various degrees of metabolic acidosis are accompanied by the decrease in the kidney function. It is known that dialysis patients' long-term convalescences and complications are related to metabolic acidosis. It is generally known that the extreme acidosis of the dialysis patients should be corrected but on the contrary, there are reports on hemodialysis patients with slight acidosis have better nutritional condition. However, the research results are rare compared to the ratio of diabetic patients among dialysis patients. Therefore, in this paper we tried to reach a conclusion by comparing and analyzing the total carbon dioxide of the serum and other nutrition parameters of the diabetic patients among long-term hemodialysis patients with the non-diabetic patients. METHODS: We divided 50 patients, who have been hemodialysis for longer than three months, into 21 patients with diabetes and 29 patients with non-diabetes. And we compared and analyzed the TCO2 in addition to measuring other parameters based on the blood tests carried out on the beginning of every month from January of 1999 to December of 2000. RESULTS: TCO2 showed a inverse correlation with nPCR, serum albumin, blood urea nitrogen, and creatinine on the correlation analysis of the total target patients. And blood urea nitrogen and age were the independent factors in the independent factor analysis using multiple regression analysis. When we divided and compared the total target patients into diabetic patients and non-diabetic patients, there were no significant differences between various kinds of nutrition parameters and dialysis parameters. And TCO2 showed a inverse correlation with nPCR, nPCR being the independent factor in the diabetic patients. In addition, TCO2 showed a inverse correlation with serum creatinine, serum creatinine being the independent factor in the non-diabetic patients. CONCLUSION: Increase of ingestion of protein was one of the important factors in inducing metabolic acidosis, but the TCO2 and improved nutritional condition resulting from ingesting sufficient protein could be preserved in the diabetic patients. Therefore we think that the diabetic patients' nutritional condition and supervision of their ingestion of protein is more needed as sufficient ingestion of protein is a major factor in balancing acid-base for diabetic patients than non-diabetic patients.
Acidosis ; Blood Urea Nitrogen ; Carbon Dioxide ; Convalescence ; Creatinine ; Dialysis ; Eating ; Hematologic Tests ; Humans ; Kidney ; Organization and Administration ; Renal Dialysis* ; Serum Albumin

BACKGROUND: In intravenous administration of a depolarizing neuromuscular blocker, succinylcholine is reported to produce activation of the electroencephalogram and increase cerebral blood flow and intracranial pressure. In this point, rocuronium was recently introduced as a non-depolarizing relaxant, and recommended as a safe alternative to succinylcholine. The purpose of this study was to evaluate the effects of rocuronium and succinylcholine on cerebral blood flow velocities during anesthetic induction. METHODS: Forty patients were randomly assigned into two groups. Group 1 was administrated rocuronium 0.6 mg/kg and group 2 was administrated succinylcholine 1 mg/kg for tracheal intubation after each group had intravenous administration of thiopental 5 mg/kg. The author observed changes of mean arterial pressure, arterial carbon dioxide tension, and middle cerebral arterial blood flow velocities at 5 times: before induction (control), 30 sec after thiopental administration, 30 sec, 60 sec and 90 sec after muscle relaxant administration. RESULTS: Mean arterial pressure decreased more at 30 sec after thiopental administration compared with the control (P<0.05). Middle cerebral arterial blood flow velocities were reduced at 30 sec after thiopental administration and 60 sec after rocuronium administration compared with the control (P<0.05). Middle cerebral arterial blood flow velocities were reduced at 30, 60, 90 sec after rocuronium administration compared with succinylcholine administration (P<0.05). CONCLUSIONS: We conclude that rocuronium has little effects on increasing cerebral blood flow. These result suggest that rocuronium have a less effect on increase in cerebral blood flow during neurosurgical anesthesia.
Administration, Intravenous ; Anesthesia ; Arterial Pressure ; Blood Flow Velocity* ; Carbon Dioxide ; Electroencephalography ; Humans ; Intracranial Pressure ; Intubation ; Neuromuscular Blockade ; Succinylcholine* ; Thiopental

OBJECTIVETo investigate the influence of CO(2) and He insufflation administered at different pressures on the migration and cytoskeleton of cultured human gastric cancer cells.

METHODSThe cultured gastric cancer cells MKN-45 were exposed to a CO(2) or He environment maintained at different pressures (12, 15 mm Hg). After 0, 2, 4, 6, 8 hours exposure to CO(2) or He environment, pH of the MKN-45 cells culture media was measured with blood gas analysis. The cell migration was detected with Transwell technology. The cell cytoskeleton was observed with laser confocal microscope.

RESULTSThe media pH was acid after exposure to CO(2) environment, while it was basic in the He group. The number of cells passing millipore in 12 mm Hg CO(2) or He insufflation pressure were not significantly different with control group (P>0.05), however in 15 mm Hg pressure CO(2) group, it was significantly decreased as compared to control group (P<0.01). The microfilament and microtubule in gastric cancer cell were ambiguous in 15 mm Hg pressure CO(2) group.

CONCLUSIONSThere are no obvious effects on the migration and cytoskeleton of MKN-45 cells under 12 mm Hg CO(2) insufflation pressure. The migration and cytoskeleton of MKN-45 cells can be inhibited in 15 mm Hg CO(2) pneumoperitoneum environment.

Carbon Dioxide ; administration & dosage ; Cell Line, Tumor ; Cell Movement ; Cell Survival ; Cytoskeleton ; Humans ; Pneumoperitoneum, Artificial ; Pressure ; Stomach Neoplasms ; ultrastructure

BACKGROUND: The chemical reaction of carbon dioxide absorbent and sevoflurane is known to produce compound A. However, carbon dioxide absorbents are not controlled by the Food and Drug Administration, but are treated as industrial products in some nations. Moreover, carbon dioxide absorbents differ in their capacities to produce compound A, because their chemical compositions differ. In this study, we compared the renal safety between carbon dioxide absorbent products in patients under sevoflurane anesthesia. METHODS: Eighty patients with no preexisting renal disease undergoing elective gynecologic surgery were randomly assigned to receive sevoflurane or isoflurane anesthesia with one of four carbon dioxide absorbent products (Sodasorblime(R), Sodalyme(R), Sodasorb(R), Spherasorb(R)) at the same fresh gas flow of 2 L/min. The renal safety was evaluated by changes of blood urea nitrogen (BUN), creatinine and urine N-acetyl-b-glucoseaminidase (NAG)-creatinine ratio at 24 hours and 72 hours after surgery from preoperative level. RESULTS: There was no significant difference in the renal safety indicators between carbon dioxide absorbents during sevoflurane anesthesia (P > 0.05). However, the BUN and urine NAG-creatinine ratios at 72 hours after surgery were higher in isoflurane anesthesia in some carbon dioxide absorbent groups (P = 0.03 and 0.04, respectively). CONCLUSIONS: We could not find significant differences of renal safety indicators with carbon dioxide absorbents. Although the adverse effect of carbon dioxide absorbents on renal function was not proved, consideration should be given to their contol by the regulation on their efficacy and safety because carbon dioxide absorbents can produce compound A.
Anesthesia ; Anesthetics ; Blood Urea Nitrogen ; Carbon ; Carbon Dioxide ; Creatinine ; Female ; Gynecologic Surgical Procedures ; Humans ; Inhalation ; Isoflurane ; Kidney ; Methyl Ethers ; Pilot Projects ; United States Food and Drug Administration

There are many factors affecting the successful performance of CT colonography (CTC). Adequate colonic cleansing and distention, the optimal CT technique and interpretation with using the newest CTC software by a trained reader will help ensure high accuracy for lesion detection. Fecal and fluid tagging may improve the diagnostic accuracy and allow for reduced bowel preparation. Automated carbon dioxide insufflation is more efficient and may be safer for colonic distention as compared to manual room air insufflation. CT scanning should use thin collimation of < or =3 mm with a reconstruction interval of < or =1.5 mm and a low radiation dose. There is not any one correct method for the interpretation of CTC; therefore, readers should be well-versed with both the primary 3D and 2D reviews. Polyps detected at CTC should be measured accurately and reported following the "polyp size-based" patient management system. The time-intensive nature of CTC and the limited resources for training radiologists appear to be the major barriers for implementing CTC in Korea.
Carbon Dioxide/administration & dosage ; Cathartics/therapeutic use ; Colonic Polyps/radiography ; Colonography, Computed Tomographic/*methods ; Contrast Media/administration & dosage ; Diagnosis, Computer-Assisted ; Feces ; Humans ; Imaging, Three-Dimensional ; Insufflation/methods

BACKGROUND: The most important reason for pre-operative administration of medication is to reduce anxiety. Alleviation of fear and anxiety about surgery enables patients to remain comfortable during treatment. Dexmedetomidine (DEX) is a fast-acting drug that is used as a premedication in different circumstances because it has sedative and anti-anxiolytic effects, and stable hemodynamics. It also has the advantage of intranasal administration. The aim of this study was to investigate the effects and hemodynamic stability of DEX by retrospectively analyzing cases in which DEX was administered nasally as a premedication. METHODS: Ten patients treated at Dankook University Dental Hospital, recruited between February and April 2015, received intranasal delivery of 2 µg/kg DEX, 30 minutes prior to general anesthesia. Anesthesia records of anxiety, blood pressure, respiration, pulse, estimated arterial oxygen saturation (SpO2), and partial pressure, or maximum concentration, of carbon dioxide (ETCO2) were analyzed. RESULTS: Administration of DEX prior to a general anesthetic effectively relieved anxiety. Respiratory depression, the most severe adverse effect of other sedatives, was not observed. Hemodynamic stability under general anesthesia was maintained during treatment and a reduction in emergence delirium was observed upon completion of treatment. CONCLUSIONS: Premedication administration of DEX is safe for pediatric patients undergoing dental treatment under general anesthesia.
Administration, Intranasal* ; Anesthesia ; Anesthesia, General* ; Anesthetics ; Anxiety ; Blood Pressure ; Carbon Dioxide ; Delirium ; Dexmedetomidine* ; Hemodynamics ; Humans ; Hypnotics and Sedatives ; Oxygen ; Partial Pressure ; Premedication* ; Respiration ; Respiratory Insufficiency ; Retrospective Studies

We investigated the effect of urinary alkalinization accomplished by intraperitoneal injection of sodium bicarbonate and acetazolamide on gentamicin nephrotoxicity in male Fisher 344rats. Forty rats (body weight 200-300g) were divided into four groups: control (gentamicin 20mg/kg, bid), high sodium load (gentamicin 20mg/kg, 25cc of saline, bid), low bicarbonate (gentamicin 20mg/kg, 25cc of sodium bicarbonate 100mEq/L, 2.5mg of Diamox, bid) and high bicarbonate (gentamicin 20mg/kg, 10cc of sodium bicarbonate 250mEq/L, 2.5mg of Diamox, bid) groups. All drugs and electrolyte solutions as mentioned above were administered intraperitoneally twice a day for seven days and changes in renal functions were studied. While salt loading failed to influence the severity of gentamicin nephrotoxicity, urinary alkalinization induced by bicarbonate and acetazolamide injection showed remarkable ameliorating effects on gentamicin nephrotoxicity. The high bicarbonate group exhibited more beneficial effects than the low bicarbonate group on gentamicin nephrotoxicity. So, urinary alkalinization seems to be an effective method for the prevention of gentamicin nephrotoxicity in rats.
Animal ; Bicarbonates/*administration and dosage ; Carbon Dioxide/urine ; Gentamicins/*toxicity ; Kidney Diseases/chemically induced/*prevention and control ; Male ; Random Allocation ; Rats ; Rats, Inbred F344

INTRODUCTIONPulse oximetry (SpO2) measures oxygen saturation but not alveolar ventilation. Its failure to detect alveolar hypoventilation during sedated endoscopy under oxygen supplementation has been reported. The aim of this study was to measure the masking effect of oxygen supplementation in SpO2 when alveolar hypoventilation develops during sedated endoscopy.

METHODSA total of 70 patients undergoing sedated diagnostic colonoscopy were randomly divided into two groups - oxygen supplementation group (n = 35) and room air breathing group (n = 35). SpO2 and end-tidal carbon dioxide (etCO2) were measured by non-intubated capnography during the procedure for all the patients.

RESULTSThe rise of etCO2 caused by alveolar hypoventilation was comparable in the two groups after sedation. SpO2 was significantly higher in the oxygen supplementation group than in the room air breathing group (98.6% ± 1.4% vs. 93.1% ± 2.9%; p < 0.001) at peak etCO2, and oxygen supplementation caused SpO2 to be overestimated by greater than 5% when compared with room air. SpO2 at peak etCO2 was reduced from the baseline before sedation for the oxygen supplementation and room air breathing groups by 0.5% ± 1.1% and 4.1% ± 3.1%, respectively (p < 0.001).

CONCLUSIONSpO2 alone is not adequate for monitoring alveolar ventilation during sedated endoscopy under oxygen supplementation due to possible delays in detecting alveolar hypoventilation in patients. Even if SpO2 decreases by only 1% during the procedure and its level remains near 100%, physicians should consider the onset of severe alveolar hypoventilation, which requires immediate intervention.

Adult ; Aged ; Carbon Dioxide ; analysis ; Colonoscopy ; Conscious Sedation ; Endoscopy ; Female ; Humans ; Hypoventilation ; diagnosis ; Male ; Middle Aged ; Monitoring, Intraoperative ; methods ; Oximetry ; methods ; Oxygen ; administration & dosage ; Respiration, Artificial