BACKGROUNDThe optimal ventilated status under total intravenous or inhalation anesthesia in neurosurgical patients with a supratentorial tumor has not been ascertained. The purpose of this study was to intraoperatively compare the effects of moderate hyperventilation on the jugular bulb oxygen saturation (SjO 2 ), cerebral oxygen extraction ratio (O 2 ER), mean arterial blood pressure (MAP), and heart rate (HR) in patients with a supratentorial tumor under different anesthetic regimens.

METHODSTwenty adult patients suffered from supratentorial tumors were randomly assigned to receive a propofol infusion followed by isoflurane anesthesia after a 30-min stabilization period or isoflurane followed by propofol. The patients were randomized to one of the following two treatment sequences: hyperventilation followed by normoventilation or normoventilation followed by hyperventilation during isoflurane or propofol anesthesia, respectively. The ventilation and end-tidal CO 2 tension were maintained at a constant level for 20 min. Radial arterial and jugular bulb catheters were inserted for the blood gas sampling. At the end of each study period, we measured the change in the arterial and jugular bulb blood gases.

RESULTSThe mean value of the jugular bulb oxygen saturation (SjO 2 ) significantly decreased, and the oxygen extraction ratio (O 2 ER) significantly increased under isoflurane or propofol anesthesia during hyperventilation compared with those during normoventilation (SjO 2 : t = -2.728, P = 0.011 or t = -3.504, P = 0.001; O 2 ER: t = 2.484, P = 0.020 or t = 2.892, P = 0.009). The SjO 2 significantly decreased, and the O 2 ER significantly increased under propofol anesthesia compared with those values under isoflurane anesthesia during moderate hyperventilation (SjO 2 : t = -2.769, P = 0.012; O 2 ER: t = 2.719, P = 0.013). In the study, no significant changes in the SjO 2 and the O 2 ER were observed under propofol compared with those values under isoflurane during normoventilation.

CONCLUSIONSOur results suggest that the optimal ventilated status under propofol or isoflurane anesthesia in neurosurgical patients varies. Hyperventilation under propofol anesthesia should be cautiously performed in neurosurgery to maintain an improved balance between the cerebral oxygen supply and demand.

Adolescent ; Adult ; Aged ; Anesthetics, Inhalation ; Anesthetics, Intravenous ; Arterial Pressure ; physiology ; Blood Gas Analysis ; Craniotomy ; methods ; Female ; Heart Rate ; physiology ; Humans ; Hyperventilation ; chemically induced ; physiopathology ; Isoflurane ; administration & dosage ; therapeutic use ; Male ; Middle Aged ; Propofol ; administration & dosage ; therapeutic use ; Young Adult

PURPOSE: Opioid-based intravenous patient-controlled analgesia (IV PCA) is popular method of postoperative pain control, but many patients suffer from IV PCA-related postoperative nausea and vomiting (PONV). In this retrospective observational study, we have determined independent predictors of IV PCA-related PONV and predictive values of the Apfel's simplified risk score in pursuance of identifying high-risk patients. MATERIALS AND METHODS: We analyzed 7000 patients who received IV PCA with background infusion after elective surgery. Patients who maintained IV PCA for a postoperative period of 48 hr (completion group, n=6128) were compared with those who have discontinued IV PCA within 48 hr of surgery due to intractable PONV (cessation group, n=872). Patients, anesthetics, and surgical factors known for predicting PONV were evaluated by logistic regression analysis to identify independent predictors of IV PCA related intractable PONV. RESULTS: In a stepwise multivariate analysis, weight, background infusion dose of fentanyl, addition of ketolorac to PCA, duration of anesthesia, general anesthesia, head and neck surgery, and Apfel's simplified risk score were revealed as independent risk factors for intractable PONV followed by the cessation of IV PCA. In addition, Apfel's simplified risk score, which demonstrated the highest odds ratio among the predictors, was strongly correlated with the cessation rate of IV PCA. CONCLUSION: Multimodal prophylactic antiemetic strategies and dose reduction of opioids may be considered as strategies for the prevention of PONV with the use of IV PCA, especially in patients with high Apfel's simplified risk scores.
Adult ; Analgesia, Patient-Controlled/*adverse effects ; Anesthetics, Intravenous/administration & dosage/adverse effects/therapeutic use ; Antiemetics/administration & dosage/therapeutic use ; Female ; Fentanyl/administration & dosage/adverse effects/therapeutic use ; Humans ; Male ; Middle Aged ; Multivariate Analysis ; Odds Ratio ; Postoperative Nausea and Vomiting/*drug therapy ; Retrospective Studies ; Risk Assessment/methods ; Risk Factors

OBJECTIVEIntravenous anesthetics, such as propofol, are widely used in general anesthesia. Neurodegeneration and neurocognitive impairment after exposure to propofol in neonatal rats have raised concerns regarding the safety of pediatric anesthesia. We examined the effects of neonatal propofol exposure on brain cell viability, as well as expression of hippocampal survivin and Caspase-3 mRNA and protein.

METHODSOne hundred male Sprague-Dawley rats aged 7 d that were weighed 10-15 g were randomly divided into 4 groups (n = 25 each group). Group A: the rats were injected with no drugs. Group B: the rats were intraperitoneally injected with 50 mg/kg propofol. Group C: the rats were first intraperitoneally injected with 50 mg/kg propofol and another 50 mg/kg propofol was used when the dynamic response of rats appeared again. Group D: the rats were first intraperitoneally injected with 50 mg/kg propofol and another 50 mg/kg propofol was used three times once the dynamic response of rats appeared. To study the effects of propofol exposure on respiratory and metabolic function, arterial blood was aspirated from the left ventricle of neonatal rats 2 h after discontinuation of propofol. pH, PaO(2), PaCO(2), HCO(3)(-), BE and SaO(2) were detected by blood gas analyzer. Moreover, to examine the effects of propofol exposure on short-term cellular viability, the ultrastructure of neurons was observed by transmission electron microscope and Fluoro-Jade B (FJB) staining was performed to examine neuronal degeneration in hippocampal CA1 region of neonatal rats. Survivin and Caspase-3 mRNA and protein expression in hippocampus were detected by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blotting 2 h after discontinuation of propofol.

RESULTSThe time of anesthesia maintaince in newborn rats was the longest in Group D and the time of anesthesia maintaince in Group C was longer than that in Group B. Two hours after discontinuation of propofol, pH, PaO(2), PaCO(2), HCO(3)(-), BE and SaO(2) of arterial blood in rats were not significantly different among groups A, B, C and D (P > 0.05). The structure of hippocampal neurons was normal in Group A and Group B while 100 mg/kg propofol resulted in nuclear blebbing and 200 mg/kg propofol led to nuclear fragmentation, chromatin condensation and apoptotic bodies. Cellular degeneration, as measured by Fluoro-Jade B staining, significantly increased in hippocampal CA1 region in the anesthesia groups compared with littermates in the no anesthesia group. FJB-positive stained degenerative neurons in groups B, C and D were (2.5 ± 1.3), (7.1 ± 2.3) and (9.4 ± 2.6), which were different from that in Group A (0.6 ± 0.3) (P < 0.05). Moreover, the number of FJB-positive neurons was the highest in Group D, that in Group C was more than that in Group B. At the same time point, apoptosis was measured by expression of Caspase-3 and Survivin mRNA and protein in hippocampus of rats. Caspase-3 mRNA in groups A, B and C was (0.78 ± 0.12), (0.84 ± 0.17) and (0.89 ± 0.19), while Caspase-3 protein in groups A, B and C was (0.22 ± 0.05), (0.26 ± 0.07) and (0.21 ± 0.06). Survivin mRNA in groups A, B and C was (0.56 ± 0.12), (0.58 ± 0.15) and (0.53 ± 0.16), while Survivin protein in these 3 groups was (0.24 ± 0.07), (0.21 ± 0.05) and (0.23 ± 0.06). Compared with that in Group A, Caspase-3 and Survivin mRNA and protein were not significantly different among Group B and Group C (P > 0.05). However, Caspase-3 mRNA and protein in Group D were (1.21 ± 0.14) and (0.42 ± 0.12), which were higher than that in the other 3 groups (P < 0.05). Survivin mRNA and protein in Group D were lower than that in the other 3 groups (P < 0.05).

CONCLUSIONSA high dose of propofol exposure may destroy the structure of neurons, induce neurodegeneration, increase Caspase-3 activity and inhibit survivin expression in hippocampus of newborn rats in vivo.

Anesthetics, Intravenous ; administration & dosage ; pharmacology ; Animals ; Animals, Newborn ; Blood Gas Analysis ; Caspase 3 ; genetics ; metabolism ; Dose-Response Relationship, Drug ; Gene Expression Regulation ; drug effects ; Hippocampus ; drug effects ; metabolism ; Injections, Intraperitoneal ; Male ; Microtubule-Associated Proteins ; genetics ; metabolism ; Neurons ; metabolism ; pathology ; Propofol ; administration & dosage ; pharmacology ; RNA, Messenger ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley

BACKGROUND: Perioperative respiratory adverse events remain a major cause of postoperative morbidity and mortality during pediatric anesthesia. This multicenter study was designed to evaluate the incidence of perioperative respiratory adverse events during elective pediatric surgery and to identify the risk factors for these events. METHODS: Pediatric patients undergoing elective surgery under general anesthesia in 11 hospitals were randomly selected for this prospective, multicenter study. Preanesthetic assessments, anesthetic and surgical conditions were recorded by anesthesiologists in charge. Adverse respiratory events were registered. RESULTS: Eight hundred and twenty-three patients were included. The overall incidence of any perioperative respiratory adverse respiratory event was 15.1%. The incidences of perioperative bronchospasm, laryngospasm, coughing, desaturatioin (oxygen saturation <95%), and airway obstruction were 0.1, 0.5, 10.2, 4.1, and 1.6% respectively. According to the multivariate analysis, five risk factors were identified: multiple attempts for airway device insertion, odds ratio (OR) 2.88; recent URI (< or =2 weeks), OR 1.96; induction with intravenous anesthetics, OR 1.95; airway related surgery, OR 1.88; ASA class > or =2, OR 1.62. CONCLUSIONS: Multiple attempts for airway device insertion, recent URI, induction with intravenous anesthetics, airway related surgery and ASA class > or =2 were associated with increased risk for perioperative respiratory adverse events.
Airway Obstruction ; Anesthesia ; Anesthesia, General ; Anesthetics, Intravenous ; Bronchial Spasm ; Child ; Cough ; Fees and Charges ; Humans ; Incidence ; Laryngismus ; Multivariate Analysis ; Odds Ratio ; Prospective Studies ; Risk Factors

OBJECTIVE: To establish an analytical method for the determination of GHB in beverages using GC/MS and LC/MS/MS. METHODS After beverage samples with GHB-d6 as the internal standard were extracted with ethyl acetate, then the extracts were derivatized with N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA), at last the derivateized extracts analyzed by gas chromatography- mass spectrometry. After beverage samples with GHB-d6 as the internal standard were diluted by mobile phase then directly analyzed by LC/MS/MS. Results The limit of detection was 0.2 microg/mL and both relative standard deviations for between-day and within-day assays were < 8.54% in GC/MS. The limit of detection was 2 microg/mL and both relative standard deviations for between-day and within-day assays were <8.62% in LC/MS/MS. Conclusion These methods of qualitative and quantitative analysis were found to be sensitive, accurate, rapid and suitable for the forensic toxicology to test of GHB in real cases.
Anesthetics, Intravenous/analysis* ; Beverages/analysis* ; Forensic Medicine/methods* ; Gas Chromatography-Mass Spectrometry/methods* ; Humans ; Hydrogen-Ion Concentration ; Reproducibility of Results ; Sensitivity and Specificity ; Sodium Oxybate/chemistry* ; Substance Abuse Detection/methods*

We replaced anesthesia of operations, which has done under local or general anesthesia, by MAC(monitored anesthesia care) with various patient's monitoring devices such as BIS(bispectral index). From April 2003 to March 2004, 48 cases of operations were done in MAC with supplemental equipments. Induction, maintenance of anesthesia was performed by propofol and midazolam. Pain control was done by fentanyl and ketamine. For monitoring the depth of anesthesia in real time, and BIS scale was checked and was maintained in 40-60. All anesthesias were done by the anesthesiologist that was communicated with operator for information between patient's status and operation procedures. All operations and anesthesias progressed with stability and safety, and there was no major postoperative complication. Because BIS was relatively accurate device, there was no over dose of anesthetic agents, which was induced by patient's uncertain pain complain under sedation and no anxiety of operator, that was raised by no responsive patient. BIS made possible that operation under MAC was effective and safe, operator perform it with non-stress condition and followed by good surgical result.
Anesthesia* ; Anesthesia, General ; Anesthesia, Intravenous ; Anesthetics ; Anxiety ; Conscious Sedation* ; Fentanyl ; Humans ; Ketamine ; Midazolam ; Postoperative Complications ; Propofol ; Spectrum Analysis ; Surgery, Plastic*

The purpose of the present study was to evaluate the correlation among the trial number of in vitro fertilization (IVF), preoperative anxiety, and propofol requirement for conscious sedation. One hundred and twenty six Korean women undergoing oocyte retrieval were enrolled. The target-controlled infusion by the anesthesiologist was conducted with initial target propofol concentration of 2.5 microgram/mL, which was manipulated until the sedation score 3 and desired clinical end point were achieved. A weak correlation was observed between visual analogue scale (VAS) anxiety and the dose of propofol required for the induction of conscious sedation (r=0.22, p=0.0192). A weak correlation was also found between VAS anxiety and the sedation time needed to reach the proper conscious sedation level for the procedure (r=0.181, p=0.0484). Multiple regression analysis showed that VAS anxiety, preoperative baseline prolactin level, and cortisol level had statistically significant effects on the propofol induction dose for target controlled conscious sedation. We concluded that the induction dose and time requirements for propofol in anesthesiologist- controlled conscious sedation be modified based on the preoperative anxiety level and the baseline blood concentration of stress hormone, cortisol and prolactin.
Adult ; Anesthetics, Intravenous ; *Anxiety ; *Conscious Sedation ; Female ; *Fertilization in Vitro ; Human ; Hydrocortisone/blood ; Korea ; *Ovum ; Preoperative Care ; Prolactin/blood ; *Propofol ; Regression Analysis ; Statistics ; *Tissue Harvesting

Ketamine is well known for its analgesic, bronchodilating and sympathetic stimulating effect. Hence, it has been widely used for induction of patients with hypotension or asthma and also for analgesic and sedating purposes in the ICU. We presented a 62 year old female patient with ventilator support in septic shock with refractory asthma whom we managed successfully with continuous intravenous infusion of ketamine postoperatively in the ICU. The patient had a history of asthma but had been asymptomatic recently and was scheduled for an emergent explo-laparotomy under the diagnosis of acute panperitonitis. Before the induction of anesthesia, the patient was in septic shock but no wheezing could be auscultated. After the induction of general anesthesia and endotracheal intubation, wheezing was apparent in both lung fields with a high peak inspiratory pressure. Inotropics, vasopressors and bronchodilators were promptly instituted without any improvement of asthma and the patient had to be transferred to the ICU with intubated after the operation. Clinical symptoms of asthma continued throughout the first day despite using bronchodilators under mechanical ventilation but, after starting the IV infusion of ketamine, there were decrease in the peak inspiratory pressure and wheezing with a subsequent improvement in the arterial blood gas analysis findings. We could also achieve considerable analgesic and sedating effect without any decrease in the blood pressure. The patient's general physical status improved and weaning with extubation was successfully done on the 21st day and was transferred to the general ward on the 28th day.
Anesthesia ; Anesthesia, General ; Anesthetics ; Asthma ; Blood Gas Analysis ; Blood Pressure ; Bronchodilator Agents ; Diagnosis ; Female ; Humans ; Hypotension ; Infusions, Intravenous ; Critical Care ; Intubation, Intratracheal ; Ketamine* ; Lung ; Middle Aged ; Patients' Rooms ; Respiration, Artificial ; Respiratory Sounds ; Shock, Septic* ; Status Asthmaticus* ; Ventilators, Mechanical ; Weaning

BACKGROUND: If epileptogenic foci are close to eloquent areas of the brain, awakening is needed for functional mapping during seizure surgery. In these cases adequate analgesia and sedation are needed. However sufficient dosage of intravenous anesthetics leads to many side effects. The authors used propofol and fentanyl infusion combined with scalp nerve block to reduce the severity of side effects from overdose of anesthetics. METHODS: The subjects were adult patients who would undergo awake craniotomy. After administering fentanyl 50~100 mcg intravenously, scalp nerve block was done to supraorbital, supratrochlear, auriculotemporal and lesser and greater occipital nerves of the surgical side with 0.25% bupivacaine containing 1 : 200,000 epinephrine. The anterior temporal region was infiltrated with the same local anesthetics. Oxygen was given by nasal cannula. During operation fentanyl was infused. Propofol was infused except during the awake period. Invasive arterial blood pressure, end-tidal CO2 and respiratory rate were monitored throughout the operation and arterial blood gas analysis was done intermittently. RESULTS: During total anesthesia time (410.3 39.9 min) propofol 16.2 6.3 mg/kg and fentanyl 11.9 3.7 mcg/kg were administered. The results of scalp nerve block were satisfactory. Brain swelling and transient decrease in respiratory rate were noticed in six patients and oxygen desaturation to 94% in one patient. All the patients were cooperative and the above problems were solved by reducing drug infusion rates. CONCLUSIONS: Propofol and fentanyl infusion with scalp nerve block may be an adequate method of anesthetic management for awake craniotomy.
Adult ; Analgesia ; Anesthesia ; Anesthetics ; Anesthetics, Intravenous ; Anesthetics, Local ; Arterial Pressure ; Blood Gas Analysis ; Brain ; Brain Edema ; Bupivacaine ; Catheters ; Craniotomy* ; Epinephrine ; Fentanyl ; Humans ; Nerve Block* ; Oxygen ; Propofol ; Respiratory Rate ; Scalp* ; Seizures

BACKGROUND: The dose-related effects of intravenous infusion of propofol on the rat EEG were evaluated quantitatively by spectral analysis of EEG recorded from the rat skull. METHODS: Propofol was infused into femoral vein at various concentrations ranging from 0 to 400 g/g body weight, and bipolar EEG was recorded from the rat skull and its spectrum were calculated by power spectrum analysis. The EEG electrodes were fixed at the right and left frontal, parieatal, and occipital bone on rat stereotaxic table. The density of each spectral bands(delta 1 3.25, theta 3.5 7.75, alpha 8 12.75, beta 13 31.75 Hz), total power density, median power frquency, and spectral edge frequency were derived from the spectra. RESULTS: In visual inspection of conventional EEG, low doses of propofol(100, 200 g/100 g) showed no significant changes except appearance of high frequency waves, but higher doses of propofol(300, 400 g/100 g) showed high amplitude with low frequency wave. In quantitative spectral analysis of EEG, low dose of propofol revealed no significant change except appearance of beta-waves in the frontal lobe especially. Significant EEG changes were identified during infusion of higher dose of propofol. 300 and 400 g/g of propofol revealed high amplitude and low frequency waves. Median power frequency and spectral edge frequency were significantly changed at 300 and 400 g/g of propofol in range 4.2Hz and 3.8Hz, and 12.4 Hz and 10.2 Hz respectively. CONCLUSIONS: Taken together, these findings suggest that analysis of EEG parameters derived from EEG power spectrum could be applied to determine the depth of propofol anesthesia in rats.
Anesthesia ; Anesthetics ; Animals ; Body Weight ; Electrodes ; Electroencephalography* ; Femoral Vein ; Frontal Lobe ; Infusions, Intravenous ; Occipital Bone ; Propofol* ; Radio Waves ; Rats* ; Skull ; Spectrum Analysis