Atsushi Numaguchi

Involvement of the serotonergic neuronal system in phencyclidine-induced place aversion in rats

The possible involvement of the serotonergic neuronal system in aversive motivation produced by phencyclidine [1-(1-phenylcyclohexyl)piperidine; PCP] was investigated using a place-conditioning paradigm in rats. PCP (4 mg/kg, i.p.) produced place aversion in this task as reported previously (Kitaichi K, Noda Y, Hasegawa T, Furukawa H, Nabeshima T. Acute phencyclidine induces aversion, but repeated phencyclidine induces preference in the place conditioning test in rats. Eur J Pharmacol 1996;318:7-9). The blockade of serotonin2A (5-HT2A) receptors using the antagonist ritanserin (3 and 10 mg/kg, p.o.) significantly attenuated this aversive property of PCP whereas lesions of serotonergic neurons using 5,7-dihydroxytryptamine (5,7-DHT, 100 microg/animal, i.c.v.) failed to affect it. Repeated PCP treatment (10 mg/kg, i.p. for 14 days), which is enough to diminish the stereotyped 5-HT2A receptor-mediated head-twitch behavior, also decreased the place aversion. These results suggest that the serotonergic neuronal system, specifically the 5-HT2A receptor, may play a critical role in producing PCP-induced place aversion.

Coronary arterial ectasia in a 2-year-old boy showing two symptoms of Kawasaki disease without manifesting fever

We read with great interest the recent clinical cases of incomplete Kawasaki disease with remarkable paucity of signs and symptoms reported by Thapa et al. [1] and Yilmazer et al. [2]. In the present letter, we describe a case of coronary arterial ectasia in a patient showing two symptoms of Kawasaki disease without fever. A 2-year-old boy was referred to our hospital with an 8-day history of arthralgia without fever. An elevated white blood cell count (11,500/ l) and elevated C-reactive protein (CRP) (4.1 mg/dl) were documented. Magnetic resonance imaging revealed Xuid collection in the right hip joint. Antibiotics were administered until joint Xuid culture revealed no bacterial infection. Although arthralgia improved within 7 days, CRP and erythrocyte sedimentation rate remained elevated. Further examination including chest X-ray, blood and stool cultures, viral serology, and autoantibodies revealed no abnormalities. Echocardiography was conducted to survey the focus of inXammation and revealed coronary arterial ectasia in segments 1, 5, and 6 with pericardial eVusion. Although incomplete Kawasaki disease was considered in the diVerential diagnosis, only conjunctival injection and desquamation contributed to the diagnostic criteria for Kawasaki disease, and no fever was evident during the clinical course. Aspirin was administered but immunoglobulin was not because of the unknown etiology of the coronary arterial abnormality. Echocardiography after administration of aspirin for 1 month showed deteriorated coronary arterial ectasia, especially in the right coronary artery, despite a gradual decrease in CRP (Fig. 1a). CRP normalized 45 days after disease onset and was followed by improvement of coronary arterial ectasia (Fig. 1b). Cardiac catheterization 1 year after disease onset showed no abnormalities of the coronary arteries (Fig. 2). This result prompted discontinuation of aspirin administration, after which the patient showed neither recurrence of coronary arterial ectasia nor reelevation of CRP. Accumulating data indicate that some cases of Kawasaki disease do not fulWll the classical diagnostic criteria. This so-called “incomplete Kawasaki disease” can also cause coronary arterial aneurysms or ectasia [3, 4]. Although no evidence-based diagnostic criteria have been determined for incomplete Kawasaki disease, an algorithm has been advocated for evaluation of incomplete Kawasaki disease in patients with persistent fever associated with two or three of the principal symptoms of Kawasaki disease [5]. However, the patient described herein presented with two symptoms of Kawasaki disease and persistently elevated CRP without manifesting fever during the entire clinical course, and developed coronary arterial ectasia. CRP is an acute-phase reactant, and persistent elevation has been reported as a risk T. Kato (&) Department of Pediatrics, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan e-mail: ktaichi@med.nagoya-u.ac.jp

Subcutaneous emphysema and ultrasound sonography.

Subcutaneous emphysema is not a rare complication in intensive care unit patients. Recently, ultrasound guidance for central venous puncture is becoming popular; however, the information on imaging for subcutaneous emphysema is limited. We encountered a patient complicated with severe pneumomediastinum and subsequent subcutaneous emphysema. The catheter replacement was attempted, and we examined the visuality of cervical vessels using ultrasound sonography before the intervention. Internal jugular vein itself was observed despite of subcutaneously migrated air bubble; however, the range of ultrasound image was limited, and the relationship between the vessel and the adjacent tissue was unclear.

Radial artery cannulation decreases the distal arterial blood flow measured by power Doppler ultrasound.

Radial arterial cannulation is a popular technique for continuous hemodynamic monitoring in an area of anesthesia and intensive care. Although the risk for invasive monitoring is considerable, there is scarce information about the change in blood flow of cannulated vessel after the catheterization. In the current investigation, we evaluated the change in the cannulated arterial blood flow. Six volunteers (study 1) and eight post-surgical patients (study 2) were enrolled into the studies. In the study 1, the both side of diameter of radial artery (RA), ulnar artery (UA) and dorsal branch of radial artery (DBRA) of participants were measured using power Doppler ultrasound (PDU) with or without proximal oppression. In the study 2, the diameter of RA, UA and DBRA of the both intact and cannulated side were compared. Study 1: The diameter of RA was 3.4 (0.52) [mean (SD)] mm and the proximal oppression significantly decreased the diameter to 1.8 (0.59) mm. The diameter of DBRA measured by PDU also decreased 2.0 (0.60)–1.3 (0.59) mm. Study 2: There was no difference between the diameters of right and left RA, however, the UA was larger [3.4 (0.60) vs. 2.8 (0.83) mm] and the DBRA was narrower [1.4 (0.43) vs. 2.0 (0.47) mm] in the cannulated side. The diameters of DBRA were different between the intact and cannulated side in the patients. Although there is no information of relationships between cause of severe complication and decreased flow, significant reduction of blood flow should be concerned.

Is it possible to identify by ultrasonography at a glance? A leaflet of valve or a flap of dissection.

Gao P. Liu, MD Fu S. Xue, MD* Rui P. Li, MD Chao Sun, MD Department of Anesthesiology, Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People’s Republic of China *Corresponding author at:Department ofAnesthesiology, Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 33 Ba-Da-Chu Rd, Shi-Jing-Shan District, Beijing 100144, People’s Republic of China Tel.: +86 13911177655; fax: +86 10 88772106 E-mail address: xuefushan@aliyun.com

Not only bupivacaine but also propofol is sinking in lipid

To the Editor: We read with great interest the recent article [1] and editorial [2] by Oda and Ikeda in this journal. The authors clearly demonstrated the effect of lipid emulsion on central nervous system abnormalities induced by bupivacaine toxicity using the unique experimental in vivo animal model. Although many anesthesiologists in developed countries, including Japan, would prefer to choose safer and long-acting local anesthetics, e.g., ropivacaine, basic research on the mechanism of drug toxicity and exploration of treatment for intoxication are absolutely important. Oda concluded that a lipid sink resulting from administration of the emulsion appears to play an important role for various lipophilic agents. Recently, we demonstrated that the hypnotic activity of propofol, a popular intravenous general anesthetic and one of the most lipophilic drugs, was diminished by simultaneous injection of lipid as a solvent [3]. Injection site pain of propofol is widely known and is considered to result from the increase in free aqueous fraction of the drug [4]. The coadministration of lipid solution could alleviate this pain by the decrease in free propofol caused by the lipid sink. Therefore, we hypothesized that not only injection pain but also the effect of the drugs on the central nervous system might be modified by lipid injection, similar to bupivacaine neurotoxicity. Lipid rescue is reported as effective for many other drugs besides bupivacaine. The precise mechanism is not fully understood, and further studies are required.

Identification of potential pathogenic viruses in patients with acute myocarditis using next-generation sequencing: TAKEUCHI et al.

Myocarditis is an inflammatory disease of the myocardium and leads to cardiac dysfunction and heart failure. Although viral infections are considered to be the most common etiology of myocarditis, the identification of the causative virus is still challenging. Recently, next‐generation sequencing (NGS) has been applied in the diagnosis of infectious diseases. The aim of the current study was to comprehensively analyze potential pathogenic microorganisms using NGS in the sera of patients with myocarditis. Twelve pediatric and five adult patients hospitalized for acute myocarditis were included. Serum samples in the acute phase were obtained and analyzed using NGS to detect pathogen‐derived DNA and RNA. Viral sequence reads were detected in 7 (41%) of the 17 myocarditis patients by NGS. Among these patients, detection of Epstein‐Barr virus, human parvovirus B19, torque teno virus, and respiratory syncytial virus reads by NGS was consistent with polymerase chain reaction or antigen test results in one patient each. A large number of human pegivirus reads were detected from one patient by RNA sequencing; however, its pathogenicity to human is unknown. Conversely, the number of detected virus‐derived reads was small in most cases, and the pathophysiological role of these viruses remains to be clarified. No significant bacterial or fungal reads other than normal bacterial flora was detected. These data indicate that comprehensive detection of virus‐derived DNA and RNA using NGS can be useful for the identification of potential pathogenic viruses in myocarditis.

Successful infant pneumonectomy with unilateral pulmonary artery occlusion test

The use of unilateral pulmonary artery occlusion (UPAO) test for the preoperative evaluation of pneumonectomy was reported in adult patients. On the contrary, in infants, no strategies have yet been recommended to predict hemodynamics after pneumonectomy, nor has use of the UPAO test been reported. We describe the first case of infant with abnormal pulmonary circulation in whom successful pneumonectomy was performed after preoperative evaluation using UPAO test. Right pneumonectomy was planned for an 8-month-old girl, because of decreased right pulmonary function, high risk of pneumothorax, and impaired left lung expansion due to overexpansion caused by severe left bronchial stenosis and bronchomalacia. However, she had also prolonged pulmonary hypertension and there was difficulty in accurate echocardiographic evaluation of its severity due to concomitant left pulmonary artery stenosis. Furthermore, contrast-enhanced computer tomography suggested a certain degree of right pulmonary venous flow, discordant with the result showing scarce right pulmonary flow in perfusion scintigraphy. Predicting postoperative hemodynamic changes was therefore considered difficult. To evaluate these concerns, we performed cardiac catheterization and UPAO test to simulate postoperative hemodynamics. Pulmonary arteriography showed decreased but significant right pulmonary arterial and venous flows. Measurements including pulmonary artery pressure and cardiac index showed no marked changes after occlusion. Based on UPAO test results, the operation was successfully performed and hemodynamics remained stable postoperatively. The UPAO test may be useful for infants with cardiopulmonary impairment to evaluate the tolerability of pneumonectomy.

Fournier’s gangrene during ACTH therapy

Fourniers gangrene is an infectious necrotizing fasciitis of the perineal, genital, or perianal regions and is uncommon in children. Adrenocorticotropic hormone (ACTH) is effective for the treatment of infantile spasms; however, suppression of immune function is one of the major adverse effects of this approach. We encountered a 2-month-old boy with infantile spasms that had been treated with ACTH and had developed complicating Fourniers gangrene. Strangulation of a right inguinal hernia was observed after ACTH treatment. Although surgical repair was successful and no intestinal injuries were detected, swelling and discoloration of the right scrotum developed in association with pyrexia and a severe inflammatory response. A scrotal incision revealed pus with a putrid smell. The patient was subsequently diagnosed with Fourniers gangrene complicated by septic shock and disseminated intravascular coagulation. Extensive debridement and intensive care was performed. Enterobactor aerogenes, methicillin-resistant Staphylococcus aureus, and Enterococcus faecalis were isolated from the pus. Meropenem, teicoplanin, and clindamycin were administered to control the bacterial infection. The patient was discharged from the intensive care unit without any obvious neurological sequelae. Suppression of immune function associated with ACTH therapy may have been related to the development of Fourniers gangrene in this case.

Ultrasonography-guided radial artery catheterization and further optimal sequences

The recent paper electronically published in the journal by Kucuk et al. [1] introduced important results and evidences for our anesthesiologists. They demonstrated that the ultrasonography-guided radial artery catheterization was optimized with forty-five degree wrist angulation. The advantages of using ultrasonography compared with the conventional technique using a detection of pulsation has been establishing in the world [2]. The study by Kucuk et al. [1] is a further dimensional one. Although Bobbia et al. [3] reported that ultrasonography-guided arterial puncture increased the number and duration of implementations, the advantages using ultrasonography apparatus would become more and more obvious in recent clinical situations [2, 4–8]. Not only arterial cannulation but also almost all of vascular access should be recommended in view point of efficacy and safety [4, 9]. Regional nerve block for analgesia is one of the most progressive area of anesthesiology in accordance with the spreading of ultrasonography [10]. Now, we should investigate the most appropriate sequences for introducing the needle under the guidance of ultrasonography. Classical and conventional approach might not be appropriate for the new devices. The optimized technique would be different from old and traditional manner [1, 11]. We developed a new combination with the unique device and ultrasound technique [12]. The further investigation is absolutely required. The multiple arterial puncture has been believed as a serious risk factor for the catheter-related complications [13]. Therefore, the best way to success the single puncture and subsequent catheterization would be absolutely needed. Recently, we experienced the two impressive cases of patients developed arterial catheterization-related cellulitis at the puncture site and systemic sepsis [14]. Both patients had received a pacemaker implantation. During the intensive care for acute heart failure, the blood culture was positive in one patient (Methicillin sensitive staphylococcus epidermidis). We administered the appropriate dose of antibiotics (cefazorlin) and maintained intensive monitoring including echocardiography, however, there was a serious risk of device infection during the progress. The details of procedures for arterial catheterization were not disclosed from the medical charts, however, the monitoring records showed that the time between the admission to the intensive care unit and the start of invasive arterial blood pressure monitoring was more than 1 h. The delay of monitoring suggested the difficulty of arterial catheterization with recurrent punctures at the admission. The repeated penetration of skin by needles could devastate the fundamental immune barrier [13, 15]. Ultrasonography-guided radial artery catheterization and optimal sequences will be beneficial for reducing the rate of infection, one of the most severe complications in an intensive care unit, by terminating the meaningless multiple punctures.