Surgical Video Projection onto a Mannequin: An Educational Tool for Simulation Practice of Perioperative Anesthetic Management.

Simulation practice is known to be effective in anesthesiology education. In our simulation practice of general anesthesia for open cholecystectomy at the Tohoku University simulation center, we projected a surgical video onto a mannequin's abdomen. In this observational study, we investigated whether video-linked simulation practice improved students' performance. We retrospectively compared the general anesthesia simulation practice scores of fifth-year medical students in a video-linked or conventional group. In the simulation practice, we evaluated the performance of each group in three sections: perioperative analgesia, intraoperative bleeding, and arrhythmia caused by abdominal irrigation. The primary endpoint was the total score of the simulation practice. The secondary endpoints were their scores on each section. We also investigated the amount of bleeding that caused an initial action and the amount of bleeding when they began to transfuse. The video group had significantly higher total scores than the conventional group (7.5 [5-10] vs. 5.5 [4-8], p = 0.00956). For the perioperative analgesia and arrhythmia sections, students in the video group responded appropriately to surgical pain. In the intraoperative bleeding section, students in both groups scored similarly. The amount of bleeding that caused initial action was significantly lower in the video group (200 mL [200-300]) than in the conventional group (400 mL [200-500]) (p = 0.00056).Simulation practice with surgical video projection improved student performance. By projecting surgical videos, students could practice in a more realistic environment similar to an actual case.

Association between the Depth of Sevoflurane or Propofol Anesthesia and the Incidence of Emergence Agitation in Children: A Single-Center Retrospective Study.

In the present study, we investigated the hypothesis that the depth of general anesthesia affects emergence agitation (EA) in children in the early postanesthetic period. We retrospectively examined male and female children (aged 1-9 years) who underwent ambulatory surgery that lasted < 2 h. Various parameters, including the modified Yale Preoperative Anxiety Score (mYPAS) before anesthesia induction, the Pediatric Anesthesia Emergence Delirium (PAED) score at recovery time, and the value of the patient state index (PSI), were extracted from our electronic anesthesia database. The relationships between the PAED score and the mean PSI values were examined with univariate analyses. We also investigated the associations among the mean PSI, propofol anesthesia, age, mYPAS, the type of surgery, and the total amount of fentanyl divided by body weight with the PAED score using multiple regression analysis with interaction terms. There were 32 and 34 patients in the sevoflurane and propofol groups, respectively. The PAED scores (all patients: r = -0.34, p = 0.0048; sevoflurane group: r = -0.37, p = 0.036) were negatively correlated with the mean PSI, whereas the PAED score in the propofol group [r = 0.31 (-0.03, 0.59), p = 0.073] did not show a significant positive correlation with the mean PSI in the univariate analysis. The multiple linear regression analysis outcomes revealed that the mean PSI value was an independent clinical factor associated with the PAED score. Intraoperative electroencephalogram monitoring may be proved as one of the useful tools for the assessment of EA risks in children.

Prediction of the development of delirium after transcatheter aortic valve implantation using preoperative brain perfusion SPECT.

OBJECTIVES: Delirium is an important prognostic factor in postoperative patients undergoing cardiovascular surgery and intervention, including transcatheter aortic valve implantation (TAVI). However, delirium after transcatheter aortic valve implantation (DAT) is difficult to predict and its pathophysiology is still unclear. We aimed to investigate whether preoperative cerebral blood flow (CBF) is associated with DAT and, if so, whether CBF measurement is useful for predicting DAT. METHODS: We evaluated CBF in 50 consecutive patients before TAVI (84.7±4.5 yrs., 36 females) using 99mTc ethyl cysteinate dimer single-photon emission computed tomography. Preoperative CBF of the DAT group (N = 12) was compared with that of the non-DAT group (N = 38) using whole brain voxel-wise analysis with SPM12 and region of interest-based analysis with the easy-Z score imaging system. Multivariable logistic regression analysis with the presence of DAT was used to create its prediction model. RESULTS: The whole brain analysis showed that preoperative CBF in the insula was lower in the DAT than in the non-DAT group (P<0.05, family-wise error correction). Decrease extent ratio in the insula of the DAT group (17.6±11.5%) was also greater relative to that of the non-DAT group (7.0±11.3%) in the region of interest-based analysis (P = 0.007). A model that included preoperative CBF in the insula and conventional indicators (frailty index, short physical performance battery and mini-mental state examination) showed the best predictive power for DAT (AUC 0.882). CONCLUSIONS: These results suggest that preoperative CBF in the insula is associated with DAT and may be useful for its prediction.

Arterial blood pressure correlates with 90-day mortality in sepsis patients: a retrospective multicenter derivation and validation study using high-frequency continuous data.

OBJECTIVE: To identify the outcome of patients with sepsis using high-frequency blood pressure data. MATERIALS AND METHODS: This retrospective observational study was conducted at a university hospital ICU (derivation study) and at two urban hospitals (validation study) with data from adult sepsis patients who visited the centers during the same period. The area under the curve (AUC) of blood pressure falling below threshold was calculated. The predictive 90-day mortality (primary endpoint) area under threshold (AUT) and critical blood pressure were calculated as the maximum area under the curve of the receiver operating characteristic curve (AUCROC) and the threshold minus average AUT (derivation study), respectively. For the validation study, the derived 90-day mortality AUCROC (using critical blood pressure) was compared with Sequential Organ Failure Assessment (SOFA), Simplified Acute Physiology Score (SAPS) II, Acute Physiology and Chronic Health Evaluation (APACHE) II, and APACHE III. RESULTS: Derivation cohort (N = 137): the drop area from the mean blood pressure of 70 mmHg at 24-48 hours most accurately predicted 90-day mortality [critical blood pressure, 67.8 mmHg; AUCROC, 0.763; 95% confidence interval (CI), 0.653-0.890]. Validation cohort (N = 141): the 90-day mortality AUCROC (0.776) compared with the AUCROC for SOFA (0.711), SAPSII (0.771), APACHE II (0.745), and APACHE III (0.710) was not significantly different from the critical blood pressure 67.8 mmHg (P = 0.420). CONCLUSION: High-frequency arterial blood pressure data of the period and extent of blood pressure depression can be useful in predicting the clinical outcomes of patients with sepsis.

Influences of environmental noise level and respiration rate on the accuracy of acoustic respiration rate monitoring.

We tested the hypothesis that the environmental noise generated by a forced-air warming system reduces the monitoring accuracy of acoustic respiration rate (RRa). Noise levels were adjusted to 45-55, 56-65, 66-75, and 76-85 dB. Healthy participants breathed at set respiration rates (RRset) of 6, 12, and 30/min. Under each noise level at each RRset, the respiration rates by manual counting (RRm) and RRa were recorded. Any appearance of the alarm display on the RRa monitor was also recorded. Each RRm of all participants agreed with each RRset at each noise level. At 45-55 dB noise, the RRa of 13, 17, and 17 participants agreed with RRset of 6, 12, and 30/min, respectively. The RRa of 14, 17, and 16 participants at 56-65 dB noise, agreed with RRset of 6, 12, and 30/min, respectively. At 66-75 dB noise, the RRa of 9, 15, and 16 participants agreed with RRset of 6, 12, and 30/min, respectively. The RRa of one, nine, and nine participants at 76-85 dB noise agreed with RRset of 6, 12, and 30/min, respectively, which was significantly less than the other noise levels (P < 0.05). Overall, 72.9% of alarm displays highlighted incorrect values of RRa. In a noisy situation involving the operation of a forced-air warming system, the acoustic respiration monitoring should be used carefully especially in patients with a low respiration rate.

[Effects of Anesthetics on Perioperative Short-term Outcomes in Patients Undergoing Thoracic Surgery with One-lung Ventilation].

BACKGROUND: The present study was designed to evaluate the postoperative values such as body temperature (BT), white blood cells (WBC), P/F ratio and C-reactive protein (CRP) associated with propofol or sevoflurane in patients undergoing thoracic surgery with one-lung ventilation. METHODS: We retrospectively reviewed outcomes of patients undergoing video-associated thoracic surgery of the esophagus (VATS-E) with propofol (group P, n = 71) or sevoflurane (group S, n = 34). Data were taken at 1 POD and 2 POD in ICU. In addition, data of WBC and CRP were taken just before the operation and on 5 POD. Statistical analyses used t-value and two-way ANOVA with statistic significance as P < 0.05. RESULTS: There was no significant difference between the two groups and we could not find the correlation between anesthetics and each factor. CONCLUSIONS: Propofol and sevoflurane had similar effect on BT, WBC, P/F ratio and CRP in patients undergoing thoracic surgery with one-lung ventilation.

Anesthetic management for abdominal aortic surgery in a patient with a left ventricular assist device: a case report.

Left ventricular assist devices (LVAD) are a currently established destination and bridge therapy until cardiac transplantation; hence, this patient population continues to increase. Here, we present the first report of abdominal aortic cross-clamping (ACC) in a LVAD patient undergoing emergency aneurysm repair. Anticoagulation was continued pre-and intra-operatively to avoid pump thrombosis. The pumping function of the LVAD is highly dependent on both preload and afterload. In this case, abdominal ACC, which increases the afterload, did not significantly influence circulatory dynamics. However, when the abdominal ACC was released, mean atrial pressure (MAP) fell to 42 mmHg, because preload reduction due to massive bleeding (3532 g) secondary to anticoagulation and afterload reduction by abdominal ACC release combined to cause critical hypotension. Maintenance of MAP required rapid infusion and use of an alpha-adrenergic agent. Surgical and anesthesia times were 411 and 525 min, respectively. Total blood loss was 5389 g, respectively. The patient was discharged after 25 postoperative days with no major complications. ACC release, with its accompanying decrease in preload and afterload, and massive bleeding due to anticoagulation in these patients require careful management.

[Perioperative management of lung transplantations in patients with pulmonary arterial hypertension compared with that in patients with lymphangiomyomatosis].

BACKGROUND: The number of lung transplantation has tended to increase as a treatment for patients with pulmonary arterial hypertension (PAH) and lymphangiomyomatosis (LAM) in Japan. However, we have little evidence about the comparison of perioperative management in patients with PAH and that in patients with LAM. METHODS: In this retrospective study, ten patients with PAH and seventeen patients with LAM who underwent the lung transplantations between 2006 and 2011 were enrolled. RESULTS: PAH patients received double lung transplantation with intraoperative cardiopulmonary bypass (CPB) support. Before anesthesia induction, percutaneous cardiopulmonary support (PCPS) was begun. Most of LAM patients received single lung transplantation without using CPB support and PCPS support before anesthesia induction. But sometimes during an operation PCPS support was necessary. Postoperative PCPS support showed no significant differences between PAH and LAM. The four year survival rate was 80% (PAH) and 87.8% (LAM). Pao2/FIo2 in patients with PAH and in those with LAM, %FEV10 in those with LAM after surgery improved when compared to those before surgery. CONCLUSIONS: The large difference in perioperative management between patients with PAH and those with LAM is an important knowledge for anesthesist.

[Seventeen cases of lung transplantations for lymphangioleiomyomatosis].

BACKGROUND: The number of lung transplantation has tended to increase as a treatment for patients with pulmonary lymphangioleiomyomatosis (LAM) in Japan. However, we have little evidence about the correlation between preoperative medical parameters and intraoperative complications. METHODS: A retrospective study was performed in 17 patients with LAM undergoing the lung transplantations between 2006 and 2011. RESULTS: Major intraoperative complications were as follows: hypotension, pulmonary hypertension, hypoxemia and blood loss of more than 1,000 ml. According to the medical records, no patients was diagnosed pulmonary hypertension before surgery and no preoperative parameters predicted intraoperative pulmonary hypertension. Therefore, according to the medical records it seemed difficult to predict the risk of the intraoperative pulmonary hypertension and hypotension. Intraoperative hypoxemia and the requirements of percutaneous cardiopulmonary support (PCPS) are not associated with preoperative PaO2 and %FEV1.0. Pleurodesis and the use of PCPS were significantly correlated with an increased risk of intraoperative massive bleeding. The four year survival rate was 87.8%. %FEV1.0, PaO2/FI(O) and %DL(CO) after surgery improved when compared to those before surgery. CONCLUSIONS: Although the intraoperative complications such as hypotension, pulmonary hypertension, hypoxemia and/or massive bleeding frequently occurred in patients with LAM during the lung transplantations, it was difficult to predict them except the massive bleeding of more than 1,000 ml before surgery. However, lung transplantation is a valuable therapy for patients with end-stage LAM.

A case of congenital central hypoventilation syndrome.

We encountered a 2-year-old female infant with congenital central hypoventilation syndrome (CCHS) who underwent an abdominal operation for strangulated ileus. Prior to the surgery, at home, the infant had been receiving non-invasive positive-pressure ventilation (NPPV) support only during sleep. However, after postoperative extubation, the blood oxygen saturation (SpO(2)) decreased to approximately 90 % with NPPV during sleep alone, necessitating the use of biphasic cuirass ventilation (BCV) along with NPPV for 2 days. The infant was weaned from the BCV on hospital day 9, and was discharged from the intensive care unit (ICU) on hospital day 13. Although it has been said that CCHS is not under the control of the respiratory center, there are no reports of the true CO(2) response curves in these patients. Therefore, during respiratory management in the ICU post-surgery, we examined (with the consent of the mother) the relationship of the end-tidal carbon dioxide (ETCO(2)) to the tidal volume and respiratory rate, for a period of 6 min in the absence of sedation, using a respiratory profile monitor. Electrocardiographic and SpO(2) monitoring was also conducted at the same time, to ensure the patient's safety. In this patient, while the ETCO(2) increased, the tidal volume and respiratory rate remained unchanged. No relationship was found between the tidal volume and the respiratory rate. Various modalities have been used for the treatment of CCHS (tracheotomy, NPPV, and diaphragmatic pacing). Treatment of these patients in the ICU should be tailored to the needs of individual patients and their families.

Impact of changes of positive end-expiratory pressure on functional residual capacity at low tidal volume ventilation during general anesthesia.

PURPOSE: Several reports in the literature have described the effects of positive end-expiratory pressure (PEEP) level upon functional residual capacity (FRC) in ventilated patients during general anesthesia. This study compares FRC in mechanically low tidal volume ventilation with different PEEP levels during upper abdominal surgery. METHODS: Before induction of anesthesia (awake) for nine patients with upper abdominal surgery, a tight-seal facemask was applied with 2 cmH(2)O pressure support ventilation and 100 % O(2) during FRC measurements conducted on patients in a supine position. After tracheal intubation, lungs were ventilated with bilevel airway pressure with a volume guarantee (7 ml/kg predicted body weight) and with an inspired oxygen fraction (FIO(2)) of 0.4. PEEP levels of 0, 5, and 10 cmH(2)O were used. Each level of 5 and 10 cmH(2)O PEEP was maintained for 2 h. FRC was measured at each PEEP level. RESULTS: FRC awake was significantly higher than that at PEEP 0 cmH(2)O (P < 0.01). FRC at PEEP 0 cmH(2)O was significantly lower than that at 10 cmH(2)O (P < 0.01). PaO(2)/FIO(2) awake was significantly higher than that for PEEP 0 cmH(2)O (P < 0.01). PaO(2)/FIO(2) at PEEP 0 cmH(2)O was significantly lower than that for PEEP 5 cmH(2)O or PEEP 10 cmH(2)O (P < 0.01). Furthermore, PEEP 0 cmH(2)O, PEEP 5 cmH(2)O after 2 h, and PEEP 10 cmH(2)O after 2 h were correlated with FRC (R = 0.671, P < 0.01) and PaO(2)/FIO(2) (R = 0.642, P < 0.01). CONCLUSIONS: Results suggest that PEEP at 10 cmH(2)O is necessary to maintain lung function if low tidal volume ventilation is used during upper abdominal surgery.

Sepsis is characterized by the increases in percentages of circulating CD4+CD25+ regulatory T cells and plasma levels of soluble CD25.

The function of immune system is to protect hosts from invading microorganisms by destroying infected cells while minimizing damage to tissues. Among immune cells, CD4(+)CD25(+) regulatory T cells (Treg cells) control immune responses by limiting infectious processes. However, it remains unclear whether Treg cells are induced in systemic inflammatory response syndrome (SIRS) or infectious SIRS (i.e. sepsis). SIRS and sepsis are associated with stressful inflammatory conditions. We therefore measured CD25(+) T cells and circulating CD4(+) T cells, along with plasma levels of CD25, interleukin (IL)-6, and IL-10, in 20 septic patients (64 +/- 11 years), 16 SIRS patients (59 +/- 16 years), and control subjects: 13 elderly (60 +/- 16 years) and 14 young volunteers (28 +/- 3 years). Septic patients (23.3 +/- 11.8%, p < 0.01) showed significantly higher percentages of CD25(+) cells among CD4(+) T cells (i.e. Treg cells) than did either young (10.6 +/- 3.7%) or elderly volunteers (11.1 +/- 3.8%). The percentages of Treg cells in septic patients were higher than those in SIRS patients (12.4 +/- 6.9%, p < 0.01). Moreover, plasma levels of soluble CD25 were significantly higher in septic patients, compared to the levels in SIRS patients or volunteers (p < 0.01). No significant difference in plasma levels of IL-6 or IL-10 was found between septic patients and SIRS patients. Thus, sepsis is associated with the increased percentages of Treg cells and elevated plasma level of soluble CD25. The elevation of these parameters might be a useful marker of infections in SIRS.

Simultaneous determination of pancuronium, vecuronium and their related compounds using LC-ESI-MS.

A simultaneous determination method of quaternary amino steroidal muscle relaxants, pancuronium (PAN), vecuronium (VEC), and 17-monodesacetyl pancuronium (17-OH-PAN), 3,17-bisdesacetyl pancuronium (3,17-OH-PAN), 3-monodesacetyl vecuronium (3-OH-VEC), 3,17-bisdesacetyl vecuronium (3,17-OH-VEC) in human serum was developed using liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). The weak cation exchange cartridge was useful for the extraction of these compounds. Under optimized LC-ESI-MS conditions, these compounds were almost fully separated within 6.5 min. Linear responses over the concentration range 0.25-50.0 ng/mL were demonstrated for each compound. The developed method successfully detected VEC, 3-OH-VEC and 3,17-OH-VEC in serum intravenously administered with VEC. The level of 3-OH-VEC was higher than other compounds. This suggested that 3-OH-VEC was useful as a forensic probe in VEC administration.