Koichi Nishikawa

We report on a case of mechanical damage to the spiral-filled polyvinyl chloride endotracheal tube that occurred shortly after tracheal intubation using a channeled videolaryngoscope (Pentax airway scope). We also found this problem in two other cases among 350 neurosurgery patients over the past 5 years. Prior to intubation, we did not observe any defect in the cuff. However, the cuff could not be filled with air immediately after the intubation. Anesthesiologists should be aware that, during tracheal intubation using an airway scope, friction between the endotracheal tube and inner surface of the introducer might result in sudden rupture of the cuff.

Erythropoietin-producing uterine myoma can cause various complications such as arterial or venous thrombosis and bleeding. Therefore, caution is required in the anesthetic management of affected patients. A 57-year-old female was suspected to have an erythropoietin-producing uterine myoma and was scheduled to undergo an abdominal total hysterectomy and bilateral salpingo-oophorectomy. Preoperative levels of hemoglobin and erythropoietin were 21.9 g/dl (normal 11.5–15 g/dl) and 23.2 IU/ml (normal 4.2–23.7 IU/ml), respectively. Preoperative phlebotomy and isovolemic hemodilution were performed to prevent arterial and venous thrombosis, following previous evidence that a hemoglobin level < 16 g/dl reduces the occurrence of polycythemia vera-related complications. Fondaparinux 2.5 mg was subcutaneously injected once daily after the operation, resulting in a good perioperative course without major complications. Herein, we have described a successful perioperative management of a patient with erythropoietin-producing uterine myoma. Our findings in this case suggest that this combination of antithrombotic therapies can facilitate anesthetic management of patients with this disease.

Hip fracture is a common and serious orthopedic injury among the geriatric population, necessitating surgical treatment. We tested whether age is a significant risk factor for in-hospital mortality after surgery in this retrospective cohort study and, further, analyzed causes and pattern of death in those patients. We queried the electronic hospital records of in-patients aged over 75 years who had undergone hip fracture surgery from the start of 2010 to the end of August 2016 in our hospital, a tertiary hospital on the main island of Japan. The extracted data included patient ID, age, gender, location of fracture, ASA-PS scores, types of anesthesia, durations of anesthesia and surgery, days of hospital stay after surgery, and outcomes at hospital discharge including in-hospital death. The extracted data were divided into two groups based on the patient’s age at the time of surgery: the aged group (age of < 85) and the advanced age group (age of ≥ 85 years), and we compared patient characteristics and management variables and discharge disposition between the two groups. Eight hundred four patient records were extracted (360 in the aged and 444 in the advanced age groups). Although a smaller proportion of patients in the advanced age group could be discharged home, all-cause in-hospital mortality was also similar between the two groups (1.9 and 1.6%, aged and advanced age groups, respectively). Six patients died from advanced cancer, and five patients died of pneumonia resulting from aspiration. The results of this study suggest that age is not a clinically significant risk factor for in-hospital mortality. The possibility decreasing in-hospital mortality exists in identifying patients at risk of aspiration and preventing it.

Myasthenia gravis (MG) is an autoimmune disease characterized by the production of antibodies against the acetylcholine receptor, muscle-specific kinase (MuSK), or other proteins at the neuromuscular junction. MG with antibodies against MuSK (MuSK-MG) has been described recently. Here, we report the first case of anesthetic management of a patient with MuSK-MG undergoing an open cholecystectomy. In our case, propofol and remifentanil-based anesthesia were used for successful management without using muscle relaxants. Patients with MuSK-MG have predominantly ocular, bulbar, and respiratory symptoms that may increase the risk of aspiration. Anesthesiologists need to pay attention to perioperative respiratory failure and respiratory crisis.

A 26-YR-OLD previously healthy nulliparous woman, weighing 47.0 kg, at 26 weeks' gestation, reported a dramatic increase in left-side upper back pain immediately after defecation. Her refractory backache was noted at 13 weeks of pregnancy, but the cause of the pain had remained undiagnosed, even after the patient had experienced frequent vomiting over the last month. A computed tomography scout film showed the mediastinal shift by a large bulla in the left hemithorax (fig.A), and the gastric tube's end demonstrated the displacement of the stomach beyond the diaphragm (fig. B, arrow). The emergent laparotomy revealed the herniation of stomach, transverse colon, and spleen through a 10-cm tear of the posterolateral part of the left diaphragm, which corresponds to the most common site of Bochdalek's hernia. The mother survived to discharge, and a healthy infant was delivered subsequently by cesarean section.

Loading of GABA and glycine into synaptic vesicles via the vesicular GABA transporter (VGAT) is an essential step in inhibitory neurotransmission. As a result of the evidence linking alterations in GABAergic and/or glycinergic neurotransmission to various pain disorders, we investigated the possible influence of down-regulation of VGAT on pain threshold and behavioral responses in mice. The phenotypes of heterozygous VGAT knockout [VGAT(+/−)] mice were compared with wild-type (WT) mice using behavioral assays. In addition, GABAergic and glycinergic miniature inhibitory postsynaptic currents (mIPSCs) were recorded in dorsal horn neurons. Western blot analysis confirmed significant reduction of VGAT protein levels in VGAT(+/−) mice. However, high-performance liquid chromatography revealed that glutamate, GABA, and glycine contents in the whole brain and spinal cord were normal in VGAT(+/−) mice. Behavioral analysis of VGAT(+/−) mice showed unchanged motor coordination, anxiety, memory performance, and anesthetic sensitivity to propofol and ketamine, although thermal nociception and inflammatory pain were enhanced. Patch-clamp recordings revealed that the frequency and amplitude of glycinergic mIPSCs in lamina II neurons were reduced in VGAT(+/−) mice. Genotype differences in glycinergic mIPSCs were more evident during sustained stimulation by solutions with high potassium levels, suggesting that the estimated size of the readily releasable pool of glycine-containing vesicles was reduced in VGAT(+/−) mice. These results provide genetic, behavioral, and electrophysiological evidence that VGAT-mediated inhibitory drive alters very specific forms of sensory processing: those related to pain processing. More close examination will be needed to verify the possibility of VGAT as a new therapeutic target for the treatment of inflammatory pain.

General anesthetic-induced unresponsiveness covers a spectrum of different behavioral components, namely, (1) amnesia, (2) sedation/hypnosis, (3) analgesia, and (4) immobility. At the molecular and cellular level, anesthetic drugs have been shown to have effects on a wide rage of putative targets, such as ligand-gated ion channels (GABA, glycine, NMDA receptors), other ion channels (K+, Na+, Ca2+), and other intracellular functions. This mini-review summarizes recent topics in this research field focusing on NMDA and GABA receptors. Although ketamine blocks NMDA receptors as an open channel blocker, it has been recently shown that ketamine inhibits hyperpolarization-activated cationic currents (J Neurosci 2009) and also enhances GABA-induced currents in alpha6 GABA receptors (J Neurosci 2008). In addition, ketamine (0.5 microM, 24h) produces loss of phenotype of fast-spiking interneurons via NADPH-oxidase (Science 2007). These data suggests that ketamine have multiple molecular targets in hypnotic, analgesic and amnestic actions. Propofol has been shown to enhance two types of GABAergic inhibition: a synaptic form (phasic inhibition) regulating neural excitability via the activation of postsynaptic GABAA receptors by intermittent GABA release from presynaptic terminals ; and a persistent tonic form (tonic inhibition) generated by continuous activation of extrasynaptic GABAA receptors by low concentrations of ambient GABA. However, the roles of tonic inhibition in hypnotic actions of isoflurane and sevoflurane are less clear. In this mini review, the relative contributions of extrasynaptic GABA receptors in behavioral actions of isoflurane and sevoflurane will be discussed.

Biologic valves can sometimes have a small closure or leakage backflow jet originating from the central coaptation point. This is physiologic regurgitation that usually only requires monitoring, and not treatment.