Search

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Printability on thin heterogeneous media using ink is related to the spreadability of ink. Thus, this study focused on quantifying the spread of ink droplets by performing amorphous morphology measurements using a measurement system that generated uniform ink droplets while simultaneously acquiring high-speed images of the ink spread on a thin medium. The directions of the droplet and camera inspection were unified to ensure measurement accuracy. Back-light illumination was adopted to increase visibility and distinguish the ink spread during image acquisition. The spreadability was assessed using digital filters, a boundary detector, nonlinear regression, and statistical analysis. Digital filters removed atypical patterns caused by the heterogeneity and porosity of the medium from the images. Subsequently, boundary points were extracted from the binarized images using a Canny edge detector. The ink spread was represented by a radial model to identify the overall movement, whereby a shaded region was considered for the kinematic structure of the measurement system. The radial model was estimated from the boundary points using nonlinear regression and a simplex search. Various spreadability indices were derived from the geometric and statistical relationships between the radial model and boundary points. The proposed measurement method was verified using predefined test images. The measurement error was at the sub-pixel level. The spreadability of ink droplets with 10–100% density was further measured, and the physical properties were investigated. [ABSTRACT FROM AUTHOR]

Applying a pneumatic tourniquet provides surgeons with a bloodless surgical field. However, application of the tourniquet induces various physiological changes. We evaluated the effect of tourniquet deflation on the intracranial pressure by using ultrasonography to measure the optic nerve sheath diameter (ONSD) in patients undergoing lower limb surgery. The ONSD was measured in 20 patients at five time points: after anesthetic induction (T0) and immediately before (T1), immediately after (T2), 5 min after (T3), and 10 min after tourniquet deflation (T4). Hemodynamic and respiratory variables were recorded. The ONSD showed significant differences at each point (P < 0.001). The ONSDs at T2 and T3 were significantly greater than that at T1 (P = 0.0007 and < 0.0001, respectively). The change in the end-tidal carbon dioxide partial pressure (EtCO2) was similar to the change in the ONSD. The change in the ONSD was significantly correlated with the change in the EtCO2 after tourniquet deflation (r = 0.484, P = 0.030). In conclusion, the ONSD, as an indicator of intracranial pressure, increased after tourniquet deflation in patients undergoing lower limb surgery. This was correlated with an increased EtCO2 and arterial carbon dioxide partial pressure. Trial registration: ClinicalTrials.gov (NCT03782077). [ABSTRACT FROM AUTHOR]

At centers with pressure on rapid operating room turnover, onset time is one of the important considerations for choosing a local anesthetic drug. To hasten the onset of the block, higher concentrations of local anesthetics are sometimes used. However, the use of diluted local anesthetics may be safer. Therefore, we aimed to compare the onset times of equipotential levobupivacaine and ropivacaine at low concentrations for infraclavicular brachial plexus block. Adult patients undergoing upper extremity surgery under ultrasound-guided infraclavicular brachial plexus block at our center were randomly allocated to the levobupivacaine and ropivacaine groups. Infraclavicular brachial plexus block was induced with 0.25% levobupivacaine or 0.375% ropivacaine depending on the assigned group. The degrees of sensory and motor blockade were assessed for 40 min after the administration of local anesthetics. A total of 46 patients were included in the analysis. Infraclavicular brachial plexus block with 0.25% levobupivacaine and 0.375% ropivacaine provided sufficient surgical anesthesia. The sensory onset time of 0.375% ropivacaine was shorter than that of 0.25% levobupivacaine (group R, 15 [15.0–22.5] min; group L, 30 [17.5–35.0] min, p = 0.001). There were no significant differences in other block characteristics and clinical outcomes between the two groups. Thus, when a quicker block onset is required, 0.375% ropivacaine is a better choice than 0.25% levobupivacaine. Trial registration ClinicalTrials.gov (NCT03679897). [ABSTRACT FROM AUTHOR]

Prolonged pleural effusion after Fontan operation is a significant morbidity that leads to long hospital stays. We investigated the association of multiple risk factors, including clinical characteristics, hemodynamic parameters, and preoperative, operative, and postoperative factors, with prolonged pleural effusion after Fontan operation. Eighty-five patients who underwent a Fontan operation between January 2005 and June 2018 in our center were included in this retrospective study. Patients were divided into two groups: group 1 (n = 36, 42.4%) included those with prolonged pleural effusion, defined as lasting > 14 days after the Fontan operation, and group 2 included patients without prolonged pleural effusion. Patients with hypoplastic left heart syndrome (HLHS) were more prevalent in group 1 (n = 15, P = 0.006). No differences in age at Fontan operation, central venous pressure at Fontan operation, or hemodynamic parameters during the pre-Fontan evaluation were found between the two groups. In multivariable analysis, HLHS (P = 0.002), non-fenestration (P = 0.018), and high central venous pressure at bidirectional cavopulmonary shunt (BCPS) operation (P = 0.043) were independent risk factors for prolonged pleural effusion after Fontan operation. Adverse outcomes such as death, need for heart transplantation, and Fontan failure were not associated with prolonged pleural effusion. In conclusion, patients with HLHS and higher central venous pressure at BCPS were more likely to have a prolonged pleural effusion after Fontan operation, but fenestration was more likely to decrease prolonged effusion. We should consider closer management of fluid status before, during, and after surgery in patients with these risk factors after Fontan operation. [ABSTRACT FROM AUTHOR]

Coronary reimplantation after neoaortic reconstruction (CRANR) in the arterial switch operation (ASO) allows easy selection of accurate coronary transfer sites in the distended neoaorta. However, neoaortic valve injury may occur during coronary reimplantation. We determined whether the CRANR procedure increased the incidence of aortic valve regurgitation (AR) after ASO. Between March 1994 and August 2017, 227 patients underwent ASO. Since September 2000 CRANR has been performed on 155 patients and open coronary reimplantation (OCR) on 72. Patients who had undergone aortocoronary flaps procedures (n = 13), had early or late mortality (n = 27), or lacked data (n = 11) were excluded. We enrolled and retrospectively reviewed the medical records of 176 patients who were followed up for postoperative AR: 38 underwent OCR and 138 underwent CRANR. We compared the incidences of early and late postoperative AR in both groups. We defined mild or greater AR as "significant AR." The groups did not differ in body weight at operation, great artery relationship, and coronary artery anatomy. The incidences of significant AR at discharge were 21.1% (8/38) in the OCR group and 16.6% (23/138) in the CRANR group (p = 0.53). The freedom from significant AR at 5 years was 59.9% in the OCR group and 62.4% in the CRANR group with no difference between the two groups (p = 0.73). Moderate AR occurred in one patient in the CRANR group. No surgical intervention was required for the aortic valve in either group. ASO using the CRANR technique did not increase the incidence of postoperative early and late AR. [ABSTRACT FROM AUTHOR]

The management of pulmonary atresia with a ventricular septal defect (PA/VSD) depends on the anatomy of the pulmonary artery or on the surgical strategy used at individual institutions. In our institution, we adopted a right ventricle-to-pulmonary artery (RV-PA) shunt in 2011 as a palliative procedure for PA/VSD to overcome the disadvantages of a Blalock-Taussig shunt. We evaluated the results of the RV-PA shunt as initial palliative surgery for PA/VSD. Thirteen patients with ductus-dependent PA/VSD from August 2011 to August 2015 were enrolled. The mean age at surgery was 17.9 ± 15.3 (range 5-60) days, and the mean body weight was 2.9 ± 0.6 (range 2.2-4.0) kg. A Gore-Tex tube graft was used in all patients. We retrospectively observed intra- and postoperative complications, early and late mortality, and palliation duration to definitive repair. Left pulmonary artery angioplasty was performed as a concomitant procedure in three patients. There were no early hospital mortalities, although two inter-stage deaths occurred 34 and 47 days postoperatively: one patient died of aspiration and the other of right ventricular outflow tract (RVOT) pseudoaneurysm rupture. Two patients (15.4%) required the extracorporeal membrane oxygenation support postoperatively: one because of failure to wean from a bypass caused by persistent hypoxemia and the other because of sudden massive bleeding from the RVOT suture line in the intensive care unit 2 days postoperatively. These two patients underwent second-stage definitive repair successfully. Five patients (41.7%) required catheter intervention, for juxtaductal left pulmonary artery stenosis in three patients, right pulmonary artery stenosis in one, and shunt inflow stenosis in one. Two patients (15.4%) required re-operation because of shunt inflow stenosis and RVOT pseudoaneurysm, respectively. All patients who survived the RV-PA shunt underwent total correction at a mean interval of 13.1 months. A RV-PA shunt is an option for the initial palliation of ductus-dependent PA/VSD. Major complications can occur, including RVOT pseudoaneurysm, shunt inflow stenosis, persistent hypoxemia during the immediate postoperative period, and dehiscence of the shunt anastomosis site. Caution should be taken when performing the RV-PA shunt for palliation of PA/VSD. [ABSTRACT FROM AUTHOR]

The recently introduced pectoral nerve (Pecs) block is a simple alterative to the conventional thoracic paravertebral block or epidural block for breast surgery. It produces excellent analgesia and can be used to provide balanced anesthesia and as a rescue block in cases where performing a neuraxial blockade is not possible. In the thoracic region, a neuraxial blockade is often used to manage zoster-associated pain. However, this can be challenging for physicians due to the increased risk of hemodynamic instability in the upper thoracic level, and comorbid and contraindicated medical conditions such as coagulopathy. Here, we introduce an ultrasound-guided Pecs block for the management of herpes zoster-associated pain, which could be an effective alternative to other interventional options in the thoracic region. [ABSTRACT FROM AUTHOR]

The surgical management of transposition complex with aortic arch obstruction remains technically demanding due to anatomic complexity. Even in the recent surgical era, there are centers that address this anomaly with a staged strategy. This report presents our experiences with a one-stage repair of transposition complexes with aortic arch obstructions more than the last 10 years. Since 2003, 19 patients with a transposition of the great arteries (TGA, 2 patients) or a double outlet of the right ventricle (DORV, 17 patients) and aortic arch obstruction have undergone one-stage repair of their anomalies. The mean age was 6.7 ± 2.3 days, and the mean body weight was 3.4 ± 0.3 kg. The 2 patients with TGA exhibited coarctation of the aorta. The 17 patients with DORV all exhibited the Taussig-Bing type. The great artery relationships were anteroposterior in 4 patients (21.1 %). The coronary artery anatomies were usual (1LCx; 2R) in 8 patients (42.1 %). There were 2 early deaths (10.5 %). Seven patients (36.8 %) required percutaneous interventions. One patient required re-operation for pulmonary valvar stenosis and left pulmonary artery patch angioplasty. The overall survival was 84.2 %. The freedom from mortality was 83.5 % at 5 years, and the freedom from intervention was 54.4 % at 5 years. The one-stage repair of transposition complexes with aortic arch obstructions resulted in an acceptable survival rate and a relatively high incidence of postoperative catheter interventions. Postoperative catheter interventions are highly effective. Transposition complexes combined with aortic arch obstructions can be managed by one-stage repair with good early and midterm results. [ABSTRACT FROM AUTHOR]

Illumination is one of the inspection conditions in industrial machine vision and highly related with image quality. Single light source is commonly used and adjusted to acquire fine images during setup. The image acquisition is described by nonlinear and complex equations, and a color mixing source additionally requires multi-dimensional formulation. So, this paper applied a direct, nondifferential, multi-dimensional search method for optimal illumination conditions using pattern search. The pattern search is one of the optimum methods and was modified for this optimal illumination and multiple color sources in machine vision. The pattern search in this paper was discussed about how to organize a probe network for this optimal illumination of image acquisition. The pattern search was composed of probe network of multiple dimensions, probing sharpness, translation, shrinkage, and terminal condition. The proposed method can maximize image sharpness and minimize iterative adjustment in the test results of an RGB mixer, which was more effective than the case of equal step search. The pattern search algorithm for this optimal illumination provides automatic and quick lighting control in image inspection process. The proposed method decreased the iterations under 1% of conventional search, and it is very efficient on time and energy saving. [ABSTRACT FROM AUTHOR]

We report the complete genome sequence of Zymomonas mobilis ZM4 (ATCC31821), an ethanologenic microorganism of interest for the production of fuel ethanol. The genome consists of 2,056,416 base pairs forming a circular chromosome with 1,998 open reading frames (ORFs) and three ribosomal RNA transcription units. The genome lacks recognizable genes for 6-phosphofructokinase, an essential enzyme in the Embden-Meyerhof-Parnas pathway, and for two enzymes in the tricarboxylic acid cycle, the 2-oxoglutarate dehydrogenase complex and malate dehydrogenase, so glucose can be metabolized only by the Entner-Doudoroff pathway. Whole genome microarrays were used for genomic comparisons with the Z. mobilis type strain ZM1 (ATCC10988) revealing that 54 ORFs predicted to encode for transport and secretory proteins, transcriptional regulators and oxidoreductase in the ZM4 strain were absent from ZM1. Most of these ORFs were also found to be actively transcribed in association with ethanol production by ZM4. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article on the case of a four-month-old patient who was diagnosed with a small secundum atrial septal defect and tetralogy of Fallot in the 2011 issue.