Effectiveness of Electroconvulsive Therapy Augmentation on Clozapine-Resistant Schizophrenia

OBJECTIVE: This retrospective case series study of the effectiveness of electroconvulsive therapy (ECT) augmentation on clozapine-resistant schizophrenia was conducted by EMR review. METHODS: Clozapine-resistance was defined as persistent psychotic symptoms despite at least 12 weeks of clozapine administration with blood levels over 350 ng/mL in order to rule out pseudo-resistance. Seven in-patients who were taking clozapine and treated with ECT were selected. We analyzed the psychopathology and subscales changed by ECT. RESULTS: The average number of ECT sessions was 13.4 (±4.6). Total Positive and Negative Syndrome Scale (PANSS) score was significantly reduced by 17.9 (±12.8) points (p=0.0384) on average, which represented a reduction of 25.5% (±14.3). 71.4% (5/7) of patients were identified as clinical remission, with at least a 20% reduction in PANSS score. PANSS reduction was associated with number of ECT sessions, stimulus level in the final session, and blood clozapine levels before ECT. However, the negative subscale on the PANSS were not reduced by ECT in any patient. We did not observe any persistent adverse cognitive effects. CONCLUSION: This study supports that ECT augmentation on clozapine-resistant schizophrenia reveals clinically effective and safe. Further research should be done involving a larger number of patients to investigate the effectiveness of clozapine/ECT combination therapy.

Characteristics of the similarity index in a Korean medical journal / 대한마취과학회지

BACKGROUND: Journal editors have exercised their control over submitted papers having a high similarity index. Despite widespread suspicion of possible plagiarism on a high similarity index, our study focused on the real effect of the similarity index on the value of a scientific paper. METHODS: This research examined the percent values of the similarity index from 978 submitted (420 published) papers in the Korean Journal of Anesthesiology since 2012. Thus, this study aimed to identify the correlation between the similarity index and the value of a paper. The value of a paper was evaluated in two distinct phases (during a peer-review process vs. after publication), and the value of a published paper was evaluated in two aspects (academic citation vs. social media appearance). RESULTS: Yearly mean values of the similarity index ranged from 16% to 19%. There were 254 papers cited at least once and 179 papers appearing at least once in social media. The similarity index affected the acceptance/rejection of a paper in various ways; although the influence was not linear and the cutoff measures were distinctive among the types of papers, both extremes were related to a high rate of rejection. After publication, the similarity index had no effect on academic citation or social media appearance according to the paper. CONCLUSIONS: The finding suggested that the similarity index no longer had an influence on academic citation or social media appearance according to the paper after publication, while the similarity index affected the acceptance/rejection of a submitted paper. Proofreading and intervention for finalizing the draft by the editors might play a role in achieving uniform quality of the publication.

The Effect of Positive End-Expiratory Pressure on Air Leakage: Comparison of Cuff Designs / 대한구급학회지

BACKGROUND: Recently developed taper-shaped cuffs (TG cuffs) of endotracheal tubes (ETTs) are known to have a more potent sealing effect than cylindrical high-volume low-pressure cuffs (HL cuffs) of conventional ETTs. The aim of this study was to compare TG cuffs with HL cuffs of ETTs in a bench-top model with regard to air leakage under various positive end-expiratory pressures (PEEP). METHODS: HL cuffs and TG cuffs made from PVC were included (HL group vs. TG group). A model trachea with an internal diameter (ID) of 22 mm was attached to a test lung. The test lung was ventilated using an anesthesia respirator with volume controlled mode and PEEPs of 0, 5, 10, or 15 cm H2O. Using spirometry, percentages of expired to inspired tidal volumes (TVe/i) were calculated as a measure of air leakage. RESULTS: With regard to PEEPs, the HL group showed significantly higher air leakage compared to the TG group (p < 0.0001), and a higher PEEP resulted in greater air leakage (p < 0.0001). Air leakage with higher PEEP was greater in the HL group than in the TG group at ID 7.0 mm and 7.5 mm (p = 0.0467, p = 0.0045). CONCLUSIONS: This study shows the superior sealing ability of the TG cuff during ventilation at various PEEPs.

Optiscope(R) may have less stimulation on hemodynamic changes / 대한마취과학회지

No abstract available.

Optimal effect-site concentration of remifentanil for preventing development of hypertension during tracheal intubation with inhaled desflurane induction / 대한마취과학회지

BACKGROUND: The aim of the present study was to determine the effect-site concentration of remifentanil needed to prevent haemodynamic instability during tracheal intubation with inhaled desflurane induction. METHODS: One hundred American Society of Anesthesiologists I and II female patients were randomized to receive an effect-site concentration of remifentanil of 0, 1, 2, 3, or 4 ng/ml. Induction of anaesthesia was started with intravenous injection of propofol 2 mg/kg. Ninety seconds after the completion of propofol injection, rocuronium (0.8 mg/kg) and remifentanil were administered simultaneously with 3% desflurane inhalation. Tracheal intubation was attempted 150 sec after the commencement of remifentanil administration. RESULTS: A probit model of remifentanil concentration was predictive of successful intubation without development of hypertension (P for goodness-of-fit = 0.419). The effect-site concentration of remifentanil needed to achieve successful intubation without development of hypertension in 95% of the patients was 3.3 ng/ml (95% confidence interval, 2.6-4.8 ng/ml). CONCLUSIONS: The effect-site concentration of remifentanil of 3.3 ng/ml is effective in blunting the haemodynamic response in 95% of the patients when 2.0 mg/kg of propofol induction was followed by 3% desflurane inhalation.

Elimination pharmacokinetics of sevoflurane and desflurane during the recovery phase of anesthesia

BACKGROUND: Sevoflurane and desflurane are widely used anesthetics and can be simulated in pharmacokinetic models. These models are related to steady state pharmacokinetics, As anesthetic elimination is a non-steady state process, we evaluated the elimination data of volatile anesthetics using a two-compartment model (bi-exponential function). 50, 80, and 90% context-sensitive decrement times were evaluated with this function. These times are related to awakening and cognitive function recovery. METHODS: Forty-eight healthy patients were enrolled for minimal surgery under general anesthesia. They were randomly anesthetized with either sevoflurane or desflurane. At the end of surgery, when the administration of the volatile anesthetics was discontinued, end-tidal concentrations (PE) were recorded for 15 minutes. We calculated and analyzed the fraction of anesthetic concentrations (PE/PE0) using a bi-exponential function (PE0: the last end-tidal concentration of anesthetics during anesthesia). RESULTS: A bi-exponential function was fit to the elimination data using non-linear mixed-effect modeling. It showed that the anesthetic duration had effects on the coefficients of early and late components and not on the log rate constants. The coefficient of late components increased and the coefficient of early components decreased with prolonged anesthetic duration. Irrespective to the type of anesthetics, prolonged anesthesia did not affect the context-sensitive half-life; however, a prolonged period of time was required to reach 80 and 90% decrement after prolonged anesthesia. CONCLUSIONS: Prolonged anesthetic duration slowed down the elimination of volatile anesthetics. It delayed awakeness and a return to normal cognitive function after anesthesia.

Hyperventilation delays clinical induction of desflurane

BACKGROUND: Ventilation is a major determinant of the alveolar concentration of inhaled anesthetics. Hyperventilation accelerates the equilibration of anesthetic in the lungs, but decelerates it in the brain. We evaluated this phenomenon for desflurane. METHODS: Twenty healthy subjects were enrolled after IRB approval. End-tidal concentrations of desflurane (P.DESF) were recorded during 10 minutes of mask induction with 8% desflurane. P.DESF was modeled with time and end-tidal concentrations of CO2 (P.ETCO2) using a two-exponential pharmacokinetic equation. Bispectral index (BIS) values were also measured to find out the component reflecting the cerebral concentration of desflurane. RESULTS: During induction, the rise of P.DESF could be separated into two components: early and late rises. Individual BIS values showed a higher correlation with the late component of P.DESF (P = 0.000). P.ETCO2 had two different effects on the rise of P.DESF. CONCLUSIONS: Hyperventilation hastened the early rise and delayed the late rise of P.DESF (P = 0.00, P = 0.00). Hyperventilation should be avoided to obtain rapid anesthesia induction with desflurane.

Emergence cerebral oxygen desaturation without hemodynamic compromise in pediatric patients / 대한마취과학회지

BACKGROUND: The regional cerebral oxygen saturation (rSO2) decreases significantly during ordinary anesthetic recovery in pediatric patients anesthetized with sevoflurane or desflurane. The present study examined the relationship between rSO2 and the clinical parameters associated with the degree of anesthetic recovery. METHODS: Twelve pediatric patients with American Society of Anesthesiologists physical status 1 were assigned randomly to receive anesthesia with sevoflurane or desflurane. All children underwent general anesthesia for minor surgery. After surgery, the rSO2, the age-adjusted MAC fraction of anesthetic concentration (F(E)), and the bispectral index (BIS) were recorded over a 10-minute period. The correlations between rSO2 and candidate predictors, such as F(E), BIS, anesthetic, and duration of anesthesia, were analyzed. RESULTS: All children recovered uneventfully. The lowest observed rSO2 reached 63% and the maximum decrease in rSO2 was 24%. The mean blood pressure and heart rate were maintained within clinical ranges. The decrease in rSO2 correlated positively with the F(E) (r = 0.25, P = 0.00) and the duration of anesthesia (r = 0.24, P = 0.01), and inversely with the use of sevoflurane (r = -0.30, P = 0.00). CONCLUSIONS: Despite normal parameters, cerebral desaturation occurred during the emergence of ordinary general anesthesia even without hemodynamic compromise or arterial desaturation. Cerebral desaturation might be associated with the degree of anesthetic recovery and the use of sevoflurane.

How much are patients willing to pay for prevention of postoperative nausea and vomiting? / 대한마취과학회지

BACKGROUND: Postoperative nausea and vomiting (PONV) remains a common complication of anesthesia. We tried to assess the amount patients were willing to pay for a hypothetical antiemetic that would completely prevent PONV. METHODS: Trained residents interviewed 86 patients, who were scheduled to undergo general anesthesia, and questionnaires were completed. RESULTS: Patients were willing to pay a median of 30,000 won for an antiemetic that would completely prevent PONV. The amounts patients were willing to pay correlated with age, previous history of PONV, and patient income. CONCLUSIONS: Patients assigned a value for avoidance of PONV. It is suggested that more efforts to prevent PONV would be helpful for the increase in patient satisfaction.

Hypocapnia Attenuates, and Nitrous Oxide Disturbs the Cerebral Oximetric Response to the Rapid Introduction of Desflurane

The aim of this study was to develop a nonlinear mixed-effects model for the increase in cerebral oximetry (rSO2) during the rapid introduction of desflurane, and to determine the effect of hypocapnia and N2O on the model. Twelve American Society of Anesthesiologist physical status class 1 and 2 subjects were allocated randomly into an Air and N2O group. After inducing anesthesia, desflurane was then increased abruptly from 4.0 to 12.0%. The PET(CO2), PET(DESF) and rSO2 were recorded at 12 predetermined periods for the following 10 min. The maximum increase in rSO2 reached +24-25% during normocapnia. The increase in rSO2 could be fitted to a four parameter logistic equation as a function of the logarithm of PET(DESF). Hypocapnia reduced the maximum response of rSO2, shifted the EC50 to the right, and increased the slope in the Air group. N2O shifted the EC50 to the right, and reduced the slope leaving the maximum rSO2 unchanged. The N2O-effects disappeared during hypocapnia. The cerebrovascular reactivity of rSO2 to CO2 is still preserved during the rapid introduction of desflurane. N2O slows the response of rSO2. Hypocapnia overwhelms all the effects of N2O.

Tension pneumothorax after arthroscopic shoulder surgery: A case report

While arthroscopic shoulder surgery is considered relatively safe, complications have been reported.Though rare, pneumothorax has been reported in patients undergoing arthroscopic shoulder surgery.Tension pneumothorax must be immediately recognized and treated due to its potentially life threatening consequences.The authors present a case of a patient who developed tension pneumothorax after arthroscopic shoulder surgery, and its anesthetic managements.

The effect of carbon dioxide pneumoperitoneum on baroreflex sensitivity / 대한마취과학회지

BACKGROUND: To determine if positive pressure pneumoperitoneum has adverse effects on autonomic nervous system function, we examined baroreflex sensitivity (BRS) during carbon dioxide pneumoperitoneum in patients undergoing laparoscopic surgery. METHODS: Twenty adult patients scheduled for laparoscopic gynecologic surgery were selected for the study. After general anesthesia was induced with sevoflurane, continuous electrocardiography and blood pressure were monitored. Spontaneous BRS was achieved using sequence method immediately before, and 5 minutes after, pneumoperitoneum. Heart rate variability (HRV) was also determined. RESULTS: After pneumoperitoneum, BRS decreased from 12.9 +/- 1.8 ms/mmHg to 8.1 +/- 1.1 ms/mmHg (P < 0.05), and the power of the high frequency band decreased from 237.8 ms2/Hz to 49.6 ms2/Hz (P < 0.05). CONCLUSIONS: Compared to recordings obtained before pneumoperitoneum, BRS was decreased during pneumoperitoneum. This may predispose patients undergoing laparoscopic surgery to hemodynamic instability in addition to pneumoperitoneum itself.