Asphyxiation by an inhaled foreign body is a leading cause of accidental death among children younger than 4 years. We analyzed the recent epidemiology of foreign body aspiration and reviewed the current trends in diagnosis and management. In this article, we discuss anesthetic management of bronchoscopy to remove objects. The reviewed articles total 12,979 pediatric bronchoscopies. Most aspirated foreign bodies are organic materials (81%, confidence interval [CI] = 77%-86%), nuts and seeds being the most common. The majority of foreign bodies (88%, CI = 85%-91%) lodge in the bronchial tree, with the remainder catching in the larynx or trachea. The incidence of right-sided foreign bodies (52%, CI = 48%-55%) is higher than that of left-sided foreign bodies (33%, CI = 30%-37%). A small number of objects fragment and lodge in different parts of the airways. Only 11% (CI = 8%-16%) of the foreign bodies were radio-opaque on radiograph, with chest radiographs being normal in 17% of children (CI = 13%-22%). Although rigid bronchoscopy is the traditional diagnostic "gold standard," the use of computerized tomography, virtual bronchoscopy, and flexible bronchoscopy is increasing. Reported mortality during bronchoscopy is 0.42%. Although asphyxia at presentation or initial emergency bronchoscopy causes some deaths, hypoxic cardiac arrest during retrieval of the object, bronchial rupture, and unspecified intraoperative complications in previously stable patients constitute the majority of in-hospital fatalities. Major complications include severe laryngeal edema or bronchospasm requiring tracheotomy or reintubation, pneumothorax, pneumomediastinum, cardiac arrest, tracheal or bronchial laceration, and hypoxic brain damage (0.96%). Aspiration of gastric contents is not reported. Preoperative assessment should determine where the aspirated foreign body has lodged, what was aspirated, and when the aspiration occurred ("what, where, when"). The choices of inhaled or IV induction, spontaneous or controlled ventilation, and inhaled or IV maintenance may be individualized to the circumstances. Although several anesthetic techniques are effective for managing children with foreign body aspiration, there is no consensus from the literature as to which technique is optimal. An induction that maintains spontaneous ventilation is commonly practiced to minimize the risk of converting a partial proximal obstruction to a complete obstruction. Controlled ventilation combined with IV drugs and paralysis allows for suitable rigid bronchoscopy conditions and a consistent level of anesthesia. Close communication between the anesthesiologist, bronchoscopist, and assistants is essential.

Vital organs maintain dense microvasculature to sustain the proper function of their cells. For tissue- engineered organs to function properly, artificial capillary networks must be developed. We have microfabricated capillary networks with a biodegradable and biocompatible elastomer, poly(glycerol sebacate) (PGS). We etched capillary patterns onto silicon wafers by standard micro-electromechanical systems (MEMS) techniques. The resultant silicon wafers served as micromolds for the devices. We bond the patterned PGS film with a flat film to create capillary networks that were perfused with a syringe pump at a physiological flow rate. The devices were endothelialized under flow conditions, and part of the lumens reached confluence within 14 days of culture. This approach may lead to tissue-engineered microvasculature that is critical in vital organs engineering.

While all three methods correctly identify metabolic acidosis due to unmeasured anions, which is a predictor of mortality, it remains unclear if further delineation of complex metabolic acid-base disorders using the Stewart physiochemical or the modified base excess methods is clinically beneficial.

Purpose Transversus abdominus plane (TAP) blocks are widely used for postoperative analgesia for abdominal surgical procedures. The purpose of this study was to compare the analgesic efficacy of plain bupivacaine, liposomal bupivacaine, and the mixture of plain bupivacaine with liposomal bupivacaine when used in a TAP block. Methods This study was a single centre, prospective, patient-, observer-, and surgeon-blinded, randomizedcontrolled trial in which 90 patients undergoing an open abdominal hysterectomy with a midline incision were randomized to receive a TAP block with plain bupivacaine (group bupivacaine), liposomal bupivacaine (group liposomal), or a mixture of liposomal bupivacaine and plain bupivacaine (group mixture). Primary outcomes included time to the first rescue opioid analgesic and total opioid consumption during the first 72 postoperative hours. Secondary outcomes included pain scores, patient satisfaction, incidence of hemodynamic instability, presence of local anesthetic systemic toxicity, and length of hospital stay. Results The median [interquartile range] time to first opioid was 51 [28-66] min in group bupivacaine, 63 [44-102] min in group liposomal, and 51 [24-84] min in group mixture (P = 0.20). The median [interquartile range] total opioid consumption in the first 72 postoperative hours was 208 [155-270] mg in group bupivacaine, 203 [153-283] mg in group liposomal, and 202 [116-325] mg in group mixture (P = 0.92). There were no significant differences in secondary outcomes between groups. Conclusions In this small study at risk of being underpowered, the mixture of liposomal bupivacaine with plain bupivacaine for TAP block did not improve analgesia compared with either liposomal bupivacaine or plain bupivacaine on their own. Trial registration www.clinicaltrials.gov (NCT03250507); registered 5 April 2017. Résumé Objectif Les blocs des muscles du plan transverse de l'abdomen (blocs TAP) sont fre´quemment utilise´s pour l'analge´sie postope´ratoire apre`s une intervention chirurgicale abdominale. L'objectif de cette e´tude e´tait de comparer l'efficacite´analge´sique de la bupivacaı¨ne This article is accompanied by an editorial. Please see Can J Anesth 2021; this issue.