Effect of Trendelenburg position on right and left internal jugular vein cross-sectional area.

BACKGROUND: Unlike the right internal jugular vein (RIJV), there is a paucity of data regarding the effect of the Trendelenburg position on the left internal jugular vein (LIJV). The purpose of this study is to investigate the cross-sectional area (CSA) of the LIJV and RIJV and their response to the Trendelenburg position using two-dimensional ultrasound in adult subjects. METHODS: This study enrolled fifty-eight patients with American Society of Anesthesiologists physical status class I-II who were undergoing general anesthesia. CSAs of both the RIJV and LIJV were measured with a two-dimensional ultrasound in the supine position and then in a 10° Trendelenburg position. RESULTS: In the supine position, the transverse diameter, anteroposterior diameter, and CSA of the RIJV were significantly larger than those of the LIJV (P < 0.001). Of 58 patients, the RIJV CSA was larger than the LIJV CSA in 43 patients (74.1%), and the LIJV CSA was larger than the RIJV CSA in 15 patients (25.9%). In the Trendelenburg position, CSAs of the RIJV and LIJV increased 39.4 and 25.5%, respectively, compared with the supine position. However, RIJV changed at a rate that was significantly greater than that of the LIJV (P < 0.05). Of 58 patients, the RIJV CSA was larger than the LIJV CSA in 48 patients (82.8%), and the LIJV CSA was larger than the RIJV CSA in 10 patients (17.2%). CONCLUSIONS: In supine position, the RIJV CSA was larger than the LIJV CSA. The increased CSA in the Trendelenburg position was greater in the RIJV than the LIJV.

Effect of propofol on prostaglandin E2 production and prostaglandin synthase-2 and cyclooxygenase-2 expressions in amniotic membrane cells.

PURPOSE: Surgery during pregnancy can be a cause of preterm labor or birth, possibly resulting from anesthetic agents or direct effects of surgery. This study was aimed to investigate the effect of propofol on uterine contractility by examining prostaglandin E2 (PGE2) production and the expression of PGE synthase 2 (PGES2) and cyclooxygenase-2 (COX-2) in amniotic membrane cells. METHODS: Amniotic membranes were collected from healthy full-term women who underwent cesarean section at 37-40 weeks of gestation. The amniotic cells were cultured in α-modified-Eagle's medium with 10% fetal bovine serum for 24 h at 5% CO2 in a 37 °C incubator. Then, various doses of propofol (0.01-10 µg/ml) were used for treatment for 3 h. PGE2 concentrations in conditioned media were evaluated using ELISA. PGES2 and COX-2 expression were examined using RT-PCR and Western blot. Cell viability and apoptosis were examined by MTT, ATP assays, and the TUNEL method. RESULTS: PGE2 production significantly decreased at 0.1 and 1.0 µg/ml propofol concentrations compared to controls. COX-2 and PGES2 mRNA expression was decreased in a dose-dependent manner with a significant difference at 0.1 µg/ml propofol compared to controls. The protein expression of COX-2 showed a similar result to mRNA expression, but protein expression of PGES2 was not significantly decreased. No effect of propofol was found in cell viability. CONCLUSIONS: This study showed that propofol reduced the production of PGE2 and the expression of COX-2 and PGES2 without affecting cell viability.

Effect of Propofol on microRNA Expression Profile in Adipocyte-Derived Adult Stem Cells.

MicroRNA (miRNA) pathways have been implicated in stem cell regulation. This study investigated the molecular effects of propofol on adipocyte stem cells (ASCs) by analyzing RNA expression arrays. Human ASCs were isolated by use of a liposuction procedure. ASCs were treated with saline, 50 µM propofol, or 100 µM propofol in culture media for 3 hours. After the isolation of total RNA, the expression of 76 miRNAs was evaluated with peptide nucleic acid-miRNA array analysis through denaturation and hybridization processes. Treatment with 50 µM propofol resulted in significant down-regulation of expression of 18 miRNAs and upregulation of expression of 25 miRNAs; 100 µM propofol resulted in significant downregulation of expression of 14 miRNAs and upregulation of expression of 29 miRNAs. The lowest expression was seen for miR-204, which was 0.07-fold with 50 µM propofol and 0.18-fold with 100 µM propofol. The highest expression was seen for miR-208b, which was 11.23-fold with 50 µM propofol and 11.20-fold with 100 µM propofol. Expression patterns of miRNAs were not significantly different between 50 µM and 100 µM propofol treatment. The results of this study suggest that propofol is involved in altering the miRNA expression level in human ASCs. Additional research is necessary to establish the functional effect of miRNA alteration by propofol.

Paradoxical carbon dioxide embolism during laparoscopic cholecystectomy as a cause of cardiac arrest and neurologic sequelae: a case report.

An 81-year-old male patient was scheduled for a laparoscopic cholecystectomy due to acute cholecystitis. About 50 minutes into the operation, the arterial blood pressure suddenly decreased and ventricular fibrillation appeared on the electrocardiography. The patient received cardiopulmonary resuscitation and recovered a normal vital sign. We suspected a carbon dioxide embolism as the middle hepatic vein had been injured during the surgery. We performed a transesophageal echocardiography and were able to confirm the presence of multiple gas bubbles in all of the cardiac chambers. After the operation, the patient presented a stable hemodynamic state, but showed weaknesses in the left arm and leg. There were no acute lesions except for a chronic cerebral cortical atrophy and chronic microvascular encephalopathy on the postoperative brain-computed tomography, 3D angiography and magnetic resonance image. Fortunately, three days after the operation, the patient's hemiparesis had entirely subsided and he was discharged without any neurologic sequelae.

Comparison of hepatic and renal function between inhalation anesthesia with sevoflurane and remifentanil and total intravenous anesthesia with propofol and remifentanil for thyroidectomy.

BACKGROUND: Inhalation anesthetics are an important factor for postoperative hepatic and renal dysfunction. In this regard, TIVA can reduce the risk of hepatic and renal dysfunction inherited to inhalation anesthetics. The present study was conducted to determine whether hepatic and renal functions differ after anesthesia with sevoflurane and propofol. METHODS: Two hundred patients, ASA physical status class I, II, scheduled for an elective thyroidectomy were randomly divided into two groups. Anesthesia was maintained with sevoflurane 1-2% and remifentanil in the sevoflurane group (Group S) and propofol 2-5 ug/ml and remifentanil 2-5 ng/ml at the effect site, using a target controlled infusion (TCI) pump in the TIVA group (Group T) to maintain BIS of 40-60. To evaluate the hepatic and renal function, aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN) and creatinine were tested at preoperation (baseline), postoperative 1 day and 3 days. RESULTS: AST was increased at postoperative 1 day and 3 days, compared with that of the preoperation in Group S, and postoperative 1 day in Group T, but the values were within its normal limit. ALT was not changed after anesthesia in both groups. BUN was increased at postoperative 1 day, compared with that of the preoperation in Group S, but the value was within its normal limit. Creatinine was not changed after anesthesia in both groups. CONCLUSIONS: The changes of hepatic and renal function after inhalation anesthesia with sevoflurane and TIVA with propofol and remifentanil for thyroidectomy were clinically insignificant, and there was no difference between the two methods.

Comparison of disinfective power according to application order of 70% isopropyl alcohol and 10% povidone-iodine.

BACKGROUND: Many disinfectants have been used clinically in both single and combination applications, but there have been few studies on disinfective power according to sterilization sequence when using a combination of disinfectants. The purpose of this study was to evaluate the disinfective power of a combination of 70% isopropyl alcohol and 10% povidone-iodine (PVP-I) according to sterilization sequence. METHODS: Two hundred healthy volunteers were recruited. Subjects were disinfected with a combination of 70% isopropyl alcohol and 10% PVP-I on both forearms, in varying sequence. The AP group included disinfections on the left forearm with isopropyl alcohol first followed by 10% PVP-I, while the PA group included disinfections on the right forearm with same disinfectants in reverse order. Skin cultures were obtained using cotton swabs 3 min after application of each disinfectant, and then were inoculated on blood agar plates for bacterial culture. Cultures were incubated at 37℃ under aerobic conditions for 48 hours. RESULTS: There was no significant difference in the number of positive cultures after the 1(st) disinfection (AP, 45; PA, 36, P = 0.262) or the 2(nd) disinfection (AP, 6; PA, 13, P = 0.157), suggesting that there is no relationship between disinfective power and the sequence of the disinfectants used. The number of positive cultures significantly decreased after the 2(nd) disinfection (P < 0.01), however. CONCLUSIONS: There was no significant difference in disinfective power according to sterilization sequence with 70% isopropyl alcohol and 10% PVP-I in healthy volunteers. The combination of 70% isopropyl alcohol and 10% PVP-I was more effective than disinfection with a single agent regardless of sterilization sequence.

The cardiovascular effects of midazolam co-induction to propofol for induction in aged patients.

BACKGROUND: The aim of this study was to investigate whether a small dose of midazolam and lessening the propofol dosage could prevent cardiovascular change at tracheal intubation for induction in aged patients. METHODS: Eighty patients over 65 years (ASA physical status 1, 2) scheduled for elective surgery received general anesthesia with remifentanil and propofol or midazolam. Patients in group P (n = 40) were induced with 0.9% NaCl 0.03 ml/kg, propofol 1. 2 mg/kg and remifentanil. Patients in group MP (n = 40) were induced with midazolam 0.03 mg/kg, propofol 0.8 mg/kg and remifentanil. The time taken to reach loss of consciousness (LOC) and the value of bispectral index score (BIS) at LOC were recorded. After LOC, 0.8 mg/kg of rocuronium was given and tracheal intubation was performed. The mean blood pressure (MBP) and heart rate (HR) were recorded before induction as the base value, before intubation, immediately post-intubation and 3 minutes after intubation. RESULTS: Compared with the base values, MBP at before intubation and 3 minutes after intubation was significantly decreased in group P and group MP (P < 0.05). Compared with group P, the decrease of MBP was significantly less at before intubation, immediately after intubation and 3 minutes after intubation in group MP (P < 0.05). The time taken to reach LOC was significantly decreased in group MP compared with that in group P (P < 0.05). There were no significant differences of HR at any time between the two groups. CONCLUSIONS: Co-induction with midazolam and propofol could prevent a marked BP decrease at tracheal intubation for induction in aged patients.

The effects of lidocaine and procaine on microRNA expression of adipocyte-derived adult stem cells.

BACKGROUND: The microRNA (miRNA) pathway has emerged as one of the biologic pathways implicated in stem cell regulation. miRNA is a noncoding, single-stranded RNA consisting of 20-25 nucleotides that inhibits the protein production at the step of translation. The molecular effects of lidocaine and procaine on adipose stem cells were investigated by examining RNA expression array. METHODS: Adipose stem cells were isolated from a prior abdominal liposuction procedure. The human adipose stem cells were cultured and then added to a mixture of 1 ml of culture medium plus 1 ml of 2% lidocaine or 2% procaine for the duration of 30 minutes. The expression levels of miRNAs were estimated by using peptide nucleic acid (PNA)-miRNA array analysis throughout the denaturation and hybridization processes after the isolation of miRNA. The miRNAs detected by microarray that either decreased by half fold or increased by 1.5 fold from the control level were interpreted as significant. RESULTS: According to microarray analysis there were 61 miRNAs in total, and no miRNA had decreased expression levels. The stem cells treatment with lidocaine showed 4 alteration of expression with miR-9a(*) (1.53 fold), miR-29a (1.64 fold), miR-296-5p (1.64 fold) and miR-373 (1.94 fold). The stem cells treated with procaine showed 32 miRNAs that were significantly up-regulated with a range of 1.5 to 2.06 fold. They were stem cell differentiation-related miRNAs, apoptosis and cell cycle-associated miRNAs, immunity-associated miRNAs and hormonal response-related miRNAs. CONCLUSIONS: Lidocaine and procaine affect the miRNA expression on adipose stem cells and the effect of procaine is more marked than that of lidocaine.

Dexmedetomidine sedation in ICU.

Dexmedetomidine (DEX), a highly selective α(2)-adrenergic receptor agonist, is the newest agent introduced for sedation in intensive care unit (ICU). The sedation strategy for critically ill patients has stressed light sedation with daily awakening and assessment for neurologic, cognitive, and respiratory functions, since Society of Critical Care Medicine (SCCM) guidelines were presented in 2002. The traditional GABAergic agents, including benzodiazepines and propofol, have some limitations for safe sedatives in this setting, due to an unfavorable pharmacokinetic profile and to detrimental adverse effects (such as lorazepam associated propylene glycol intoxication and propofol infusion syndrome). DEX produces it's sedative, analgesic and cardiovascular effects through α(2) receptors on the locus ceruleus (LC). Activities of LC, the tuberomammillary nucleus (TMN) are depressed and activity of the ventrolateral preoptic nucleus (VLPO) is increased during DEX sedation, which is similar in features to normal non-REM (NREM) sleep. At the same time, perifornical orexinergic activity is maintained, which might be associated with attention. This mechanism of action produces a normal sleep-like, cooperative sedation. The characteristic feature of sedation, together with a concomitant opioid sparing effect, may decrease the length of time spent on a ventilator, length of stay in ICU, and prevalence and duration of delirium, as the evidence shown from several comparative studies. In addition, DEX has an excellent safety profile. In conclusion, DEX is considered as a promising agent optimized for sedation in ICU.

Predictors of difficult intubation defined by the intubation difficulty scale (IDS): predictive value of 7 airway assessment factors.

BACKGROUND: The intubation difficulty scale (IDS) has been used as a validated difficulty score to define difficult intubation (DI). The purpose of this study is to identify airway assessment factors and total airway score (TAS) for predicting DI defined by the IDS. METHODS: There were 305 ASA physical status 1-2 patients, aged 19-70 years, who underwent elective surgery with endotracheal intubation. During the pre-anesthetic visit, we evaluated patients by 7 preoperative airway assessment factors, including the following: Mallampati classification, thyromental distance, head & neck movement, body mass index (BMI), buck teeth, inter-incisor gap, and upper lip bite test (ULBT). After endotracheal intubation, patients were divided into 2 groups based on their IDS score estimated with 7 variables: normal (IDS < 5) and DI (IDS ≥ 5) groups. The incidence of TAS (> 6) and high score of each airway assessment factor was compared in two groups: odds ratio, confidence interval (CI) of 95%, with a significant P value ≤ 0.05. RESULTS: The odds ratio of TAS (> 6), ULBT (class III), head & neck movement (< 90°), inter-incisor gap (< 4 cm), BMI (≥ 25 kg/m(2)) and Mallampati classification (≥ class III) were respectively 13.57 (95% CI = 2.99-61.54, P < 0.05), 12.48 (95% CI = 2.50-62.21, P < 0.05), 3.11 (95% CI = 0.87-11.13), 2.32 (95% CI = 0.75-7.19), 2.22 (95% CI = 0.81-6.06), and 1.22 (95% CI = 0.38-3.89). CONCLUSIONS: We suggest that TAS (> 6) and ULBT (class III) are the most useful factors predicting DI.

Difference of the hemodynamic changes induced by tracheal intubation using remifentanil between smokers and nonsmokers.

BACKGROUND: It was well-known that smoking affects the cardiovascular system, and remifentanil can suppress the sympathetic stimulations induced by tracheal intubation. The purpose of this study was to investigate whether there was any difference in the hemodynamic changes induced by tracheal intubation with using remifentanil between smokers and nonsmokers. METHODS: EIGHTY PATIENTS WERE ENROLLED: male smokers (MS), male nonsmokers (MN), female smokers (FS) and female nonsmokers (FN). Anesthesia was induced with diluted remifentanil (20 microg/ml) at a rate of 10 microg/kg/hr using an infusion pump, and 2 min later, midazolam 0.05 mg/kg and propofol 0.8 mg/kg were injected for achieving unconsciousness. Rocuronium 1 mg/kg was used for muscle relaxation, and tracheal intubation was performed 2 min after rocuronium injection. After tracheal intubation, the remifentanil was decreased to 2 microg/kg/hr. The mean arterial pressure (MAP) and heart rate (HR) were checked before induction, on unconsciousness, just before intubation, just after intubation and 1, 2 and 3 minutes after intubation, and these values were compared between the groups. RESULTS: In men, the MAP and HR just after intubation and at 1, 2 and 3 minutes after intubation in Group MS were significantly higher than those of Group MN (P < 0.05). For the women, the HR in both groups (the FS and FN groups) were increased just after intubation and 1, 2 and 3 minutes after intubation compared with that at the baseline, respectively, but there was no difference between the two groups. CONCLUSIONS: There was a difference of the hemodynamic changes induced by tracheal intubation with using remifentanil between the male smokers and nonsmokers, but not in women.

The expression of survivin and its related genes in adipocyte-derived stem cell by demethylation.

BACKGROUND: Survivin is thought to contribute to stem cell maintenance partly by a hypomethylation mechanism. This study attempted to elucidate the signal transduction pathway of adipocyte-derived stem cells (ASCs) by using a demethylating agent, 5-aza-2'-deoxycytidine (ADC), to analyze the survivin, MEK/ERK, c-Myc and p53 gene expression. METHODS: Demethylation in the ASCs was induced by 1 microM ADC treatment. RT-PCR for survivin mRNA was preformed, before and 24, 48 and 72 hours (hr) after ADC treatment. Western blotting analysis was performed for p53, survivin, unphosphorylated and phosphorylated (p)-MEK, and p-ERK. Immunohistochemistry for ERK and survivin was done to evaluate the localization of the proteins. RESULTS: ADC inhibited the population growth of the ASCs and it increased the number of apoptotic cells 24, 48, and 72 hr after treatment. ADC treatment slightly decreased the expression of survivin mRNA after 48 hr and its level was restored after 72 hr of treatment. Otherwise, the level of survivin protein gradually increased up to 48 hr and it was decreased at 72 hr. The levels of p-MEK and p53 were increased time-dependently. c-Myc and p-ERK were elevated after ADC treatment and their highest levels were seen 48 hr after treatment. The ADC treatment increased the nuclear expression of ERK and survivin in the ASCs. CONCLUSIONS: The overexpression of p-MEK/ERK, p53, and c-Myc increased the survivin protein expression of the demethylated ASCs. These results suggest that demethylation could alter the expression of survivin, and p53, c-Myc and the MAPK (MEK/ERK) pathway might play a role in survivin's regulation in ASCs.

The effects of remifentanil and lidocaine on the cardiovascular responses to tracheal intubation in hypertensive patients.

BACKGROUND: Hypertensive patients are more prone to exhibit an exaggerated hemodynamic responses to laryngoscopy and tracheal intubation. We compared the effects of remifentanil and lidocaine on the cardiovascular responses during intubation in hypertensive patients. METHODS: Fifty adult hypertensive patients (>140/90 mmHg) were divided into 2 groups (remifentanil group; 1.0 microgram/kg, n = 25, lidocaine group; 1.5 mg/kg, n = 25). After 3 minutes'oxygenation, anesthesia was induced using 0.2 mg glycopyrrolate, 1.5 mg/kg propofol, and 1 of experimental drugs (30 seconds) bolus administration. Tracheal intubation was facilitated 90 seconds after administration of rocuronium; anesthesia was maintained with 2% sevoflurane and air in oxygen. Arterial blood pressure and heart rate were measured at the following times: resting state (baseline), after oxygenation; before intubation; just after intubation; and at 1, 3, and 5 minutes after intubation. RESULTS: There was significant attenuation of mean systolic and diastolic arterial blood pressures, after intubation of the remifentanil group compared to the lidocaine group at just after intubation and at 1 minute after intubation (P < .05). The difference in heart rate was not significant between both groups. CONCLUSIONS: Bolus administration of remifentanil was found to be superior to lidocaine in the attenuation of the blood pressure during intubation in hypertensive patients.

Cerebral air embolism after removal of internal jugular venous catheter: A case report.

Air embolism can occur during central venous catheter removal. We encountered a patient diagnosed with cerebral air embolism associated with the removal of an internal jugular venous catheter. The patient was 65 years old and was admitted to the intensive care unit due to pneumonia. He had a catheter placed in the right internal jugular vein. Five days thereafter, the catheter was removed in semi-Fowler's position using the Valsalva maneuver. Immediately after the catheter removal, the patient became pale, felt dyspneic, lost consciousness and exhibited seizure activity. A neurological examination, revealed left upper arm (grade I) and lower leg paralysis (grade II) as well as left facial palsy. A brain computed tomogram showed that, air was trapped in the cavernous sinus. In diffusion weighted magnetic resonance imaging, signal changes were reported in the right frontal cortex, indicating acute cerebral infarction. Hyperbaric oxygen therapy and ventilatory support with synchronized intermittent mandatory ventilation mode was applied. Twenty days thereafter, consciousness and motor functions were recovered completely except for mild weakness of the upper arm (grade IV).