Usefulness of an automatic cuff pressure controller (SmartCuff) in inhibiting gasleakage around the cuff after tracheal intubation: a randomized controlled study.

PURPOSE: Gas leakage around the cuff of a tracheal tube may frequently occur after tracheal intubation and inflation of the cuff. We assessed if the SmartCuff (Smiths Medical Japan, Tokyo, Japan), an automatic cuff pressure controller, would effectively prevent gas leakage. METHODS: Seventy adult patients were allocated randomly to one of two groups. After induction of general anesthesia and tracheal intubation, in one group (Syringe group), a syringe was used to inflate the cuff, until there was no audible gas leakage, at the airway pressure at 20 cmH2O. In the other group (SmartCuff group), the SmartCuff was used to maintain the cuff pressure to be 20 cmH2O. The mechanical ventilation (tidal volume of 8 ml.kg-1 and 12 breaths per min) was started. The incidence and percentage of gas leakage, and the proportion of adequate seal (defined as gas leakage of < 10%) between the groups were compared. RESULTS: The incidence of audible gas leakage was significantly higher in the Syringe group (10 of 35 patients (28%)) than in the SmartCuff group (none of 35 patients (0%)) (P = 0.00046, 95%CI for difference: 15-43%), and the proportion of adequate seal was significantly lower in the Syringe group (19 of 35 patients (54%)) than in the Smart cuff group (33 of 35 patients (94%)) (P = 0.0001, 95% CI for difference: 20-58%). CONCLUSION: Gas leakage may frequently occur after tracheal intubation, and the use of the SmartCuff can effectively maintain the sealing effect of the cuff.

Efficacy of McGRATH®MAC videolaryngoscope blade 1 for tracheal intubation in small children: a randomized controlled clinical study.

BACKGROUND: Videolaryngoscopes may not be as effective in small children as they are in older children and in adults. The size 1 blade is commercially available for the McGRATH®MAC videolaryngoscope (Covidien, Medtronic, Tokyo, Japan), but its efficacy in comparison with a Macintosh laryngoscope blade 1 is not known. AIM: The main aim of this study was to assess the efficacy of McGrath®MAC blade 1 in comparison with a conventional Macintosh laryngoscope blade 1, in children aged less than 24 months. METHODS: Thirty-eight children aged less than 24 months were randomly allocated to one of two groups, and tracheal intubation was attempted using either a direct laryngoscope with a Macintosh blade 1 or a videolaryngoscope with a McGRATH®MAC blade 1. In another 12 children aged 2-4 years, the same comparisons were made with blade 2. The primary outcome measure was time to tracheal intubation using a size 1 blade. RESULTS: Tracheal intubation took significantly longer with a McGRATH®MAC blade 1 (median (interquartile range): 38.0 (31.8-43.5) s) than with the Macintosh blade 1(27.4 (25.9-29.2) s) (p < 0.0001; median difference (95% CI for the median difference): 10.6 (6.4-14.0) s), mainly due to difficulty in advancing a tube into the trachea. No significant difference was observed for the size 2. CONCLUSIONS: In small children without predicted difficult airways, time to intubate the trachea was significantly longer for a McGRATH®MAC blade 1 than a Macintosh blade 1. CLINICAL TRIAL REGISTRATION: jRCT1032220366.

A fragmented segment of a central venous catheter caused delayed ventricular fibrillation: a case report.

BACKGROUND: Central venous port systems may be safely used for chemotherapy of patients with cancer, but several complications may occur associated with their use. CASE PRESENTATION: An 83-year-old man with heat stroke was transferred to our emergency department, where he was treated and became able to eat on the same day. He had been fit and healthy, except for colorectomy and chemotherapy using a central venous access port placed in the right upper jugular vein 8 years ago. The next day, he suddenly had ventricular fibrillation. Cardiopulmonary resuscitation was successful. Emergency coronary angiography showed a catheter-like foreign body in the coronary sinus. Physicians failed to remove the foreign body using catheter therapy, and ventricular fibrillation occurred repeatedly. After induction of general anesthesia, the fractured catheter was removed surgically. Postoperative course was uneventful. CONCLUSIONS: A fragmented segment of a catheter may suddenly cause ventricular fibrillation years later.

Efficacy of an aid (gastric tube insertion guide) for oral insertion of a gastric tube: a randomized controlled trial.

PURPOSE: Insertion of a gastric tube orally may be more difficult than its insertion nasally, and thus, any aid to facilitate its insertion may be useful. Gastric tube insertion guide (Fuji Medical Corporation, Tokyo, Japan) has recently become commercially available. We felt that this device might be useful in facilitating oral insertion of a gastric tube, but there has been no formal study assessing its efficacy. The main aim of this study was to assess whether or not this "tube guide" would facilitate insertion of an orogastric tube. METHODS: As a randomized controlled clinical study, we planned to study 40 patients, to assess the hypothesis that the success rate of insertion of an orogastric tube would be higher with the use of the "tube guide" than without. Patients were recruited when they were 20 years old, or older, and allocated randomly to one of two groups (20 people each group). In one group, the conventional "blind" insertion method was used and in the other group the "tube guide" insertion method. RESULTS: The success rate was significantly higher for the "tube guide" method than the "blind" insertion method (P = 0.0012, 95% CI for difference: 23-67%). CONCLUSION: We have shown that the use of the gastric tube insertion guide® facilitates insertion of an orogastric tube.

Tracheal tube cuff pressure during anesthesia for robotic-assisted laparoscopic prostatectomy and the efficacy of an automatic cuff pressure controller (SmartCuff): observational studies of 1-sample paired data.

PURPOSE: The cuff pressure of a tracheal tube may increase during robot-assisted laparoscopic surgery for prostatectomy (RALP), which requires pneumoperitoneum in a steep head-down position, but there have been no studies which confirmed this. METHODS: In study 1, we studied how frequently the cuff pressure significantly increased during anesthesia for the RALP. In study 2, we studied if the SmartCuff (Smiths Medical Japan, Tokyo) automatic cuff pressure controller would minimize the changes in the intracuff pressure. With approval of the study by the research ethics committee (approved number: 20115), we measured the cuff pressures in anesthetized patients undergoing RALP and in those undergoing gynecological laparotomy (as a reference cohort), with and without the use of the SmartCuff. RESULTS: In 21 patients undergoing RALP, a clinically meaningful increase (5 cmH2O or greater) was observed in all the 21 patients (P = 0.00; 95% CI for difference: 86-100%), whereas in 23 patients undergoing gynecological laparotomy, a clinically meaningful decrease (5 cmH2O or greater) was observed in 21 of 23 patients (91%, P < 0.0001; 95% CI for difference: 72-99%). With the use of the SmartCuff, there was no significant increase in the incidence of a clinically meaningful change in the intracuff pressure in either cohort. CONCLUSION: The cuff pressure of a tracheal tube would frequently increase markedly in patients undergoing RALP, whereas it would frequently decrease markedly in patients undergoing gynecological laparotomy. The SmartCuff may inhibit the changes in the cuff pressure during anesthesia.

Visualization of injectate spread of intercostal nerve block: a cadaveric study.

INTRODUCTION: Intercostal nerve block and neurolysis are widely used procedures, but their injectate spread has not been well understood. Previous studies have reported unexpected outcomes (paravertebral or epidural anesthesia) and spinal cord injury after intercostal nerve block and neurolysis. To investigate a possible mechanism for these complications, we aimed to visualize the flow of liquid injected near the intercostal nerve, using cadavers. METHODS: We performed a simulated intercostal nerve block study using two Thiel-embalmed cadavers. Dye was injected into the interfascial plane between the internal and innermost intercostal muscles under ultrasound guidance (blue, 10 ml) or under direct vision (green, 5 ml). RESULTS: Dye leakage began with injection of only 0.5-2 ml and occurred between the innermost intercostal muscle fibers. The dye injected around the intercostal nerve penetrated into the extrapleural space and reached the paravertebral space. CONCLUSIONS: Injectate placed around the intercostal nerve easily penetrate the extrapleural space and reach the paravertebral space. Intercostal nerve block or neurolysis has a risk of impairing at least the sympathetic chain and conceivably affecting the central nervous system.

Anatomical basis for simultaneous block of greater and third occipital nerves, with an ultrasound-guided technique.

PURPOSE: In some headache disorders, for which the greater occipital nerve block is partly effective, the third occipital nerve is also suggested to be involved. We aimed to establish a simple technique for simultaneously blocking the greater and third occipital nerves. METHODS: We performed a detailed examination of dorsal neck anatomy in 33 formalin-fixed cadavers, and deduced two candidate target points for blocking both the greater and third occipital nerves. These target points were tested on three Thiel-fixed cadavers. We performed ultrasound-guided dye injections into these points, examined the results by dissection, and selected the most suitable injection point. Finally, this target point was tested in three healthy volunteers. We injected 4 ml of local anesthetic and 1 ml of radiopaque material at the selected point, guided with a standard ultrasound system. Then, the pattern of local anesthetic distribution was imaged with computed tomography. RESULTS: We deduced that the most suitable injection point was the medial head of the semispinalis capitis muscle at the C1 level of the cervical vertebra. Both nerves entered this muscle, in close proximity, with little individual variation. In healthy volunteers, an anesthetic injected was confined to the muscle and induced anesthesia in the skin areas innervated by both nerves. CONCLUSIONS: The medial head of the semispinalis capitis muscle is a suitable landmark for blocking the greater and third occipital nerves simultaneously, by which occipital nerve involvement in various headache disorders may be rapidly examined and treated.

[Utility of McGRATH MAC for a Patient with a Large Epiglottic Cyst].

A 76-year-old man with an epiglottic cyst was scheduled for transoral rigid endoscopic epiglottic cystectomy under general anesthesia. The epiglottic cyst was found accidentally when he had an operation of radical cystectomy 2 weeks before. When he had the radical cystectomy, the ventilation through a mask was easy. He had no subjective respiratory symptoms. We chose rapid induction with propofol, remifentanl, and rocuronium. When we inserted the McGRATH MAC laryngoscope, we could only see a big epiglottic cyst not vocal cord but the pressure on the neck enabled the laryngologist to see the vocal cord. We could identify the space through which we could insert tracheal tube without touching the cyst. After the operation, his trachea was extubed.

[The Use of a Tracheal Tube for Guiding Nasogastric Tube Insertion].

An obese patient was scheduled for shoulder joint surgery under general anesthesia. After induction of anesthesia and tracheal intubation, insertion of a gastric tube was difficult. A new tracheal tube was prepared, the connecter was removed, and the tube was cut longitudinally. The tube was inserted orally into the esophagus. A gastric tube was passed through the nose, and its tip was taken out of the mouth. The tip of the gastric tube was passed through the tracheal tube, and its correct position in the stomach was confirmed by auscultation of the epigastrium. The tracheal tube was carefully taken out from the esophagus leaving the gastric tube in the stomach. The cut tracheal tube was peeled off from the gastric tube. Correct positioning of the gastric tube was re-confirmed.

[Stroke Volume Variation (SVV) as an Indicator of Intraoperative Transfusion Management during Laparoscopic Colectomy.]

BACKGROUND: Intraoperative transfusion manage- ment is difficult during laparoscopic surgery, because peumoperitoneum affects hemodynamics. We studied whether stroke volume variation (SVV) is useful as an indicator of transfusion management Methods : We studied 44 patients undergoing lapa- roscopic colectomy. Patients were randomly allocated to two groups, and the volume of transfusion was decided with the SVV as an indicator in one group (SVV group, n=22) or with conventional indicators, such as blood pressure, heart rate, volume of urine in the other group (control group, n=22) Results : In the SVV group, total transfusion volume and total blood loss during operation were significantly decreased, and the length of hospital stay was signifi- cantly shorter, compared with the control group. CONCLUSIONS: We believe that the SVV is a useful indicator of intraoperative transfusi6h management during laparoscopic colectomy.

[Laryngeal Mask Airway for Ventilation during Fiberoptic Bronchoscopy in a Child with Bilateral Vocal Cord Palsy following Coin Lithium Battery Ingestion].

We report anesthetic management for fiberoptic laryngoscopy in a 10-month-old boy with stridor, due possibly to bilateral vocal cord palsy after coin lithium battery ingestion. After pre-oxygenation of the child, anesthesia was induced with propofol 16 mg (2 mg · kg(-1)) and rocuronium 8 mg (1 mg · kg(-1)). After assist mask ventilation with sevoflurane 5-6%, we inserted a laryngeal mask. The fiberoptic laryngoscopy was smoothly performed by passing a fiberscope through the laryngeal mask. At the end of the procedure, the patient was sent back to the ward.

[Intubation Using a Double-lumen Tube with a Combination of Fiberoptic Bronchoscope and the Glidescope in a Patient with Difficult Airway].

A 54-year-old man with lung cancer was scheduled for thoracoscopic upper lobe resection under general anesthesia. About half a year previously, he had undergone surgery for oropharyngeal cancer and tongue cancer. As a result of the surgery, elasticity of the neck skin bending of the neck were restricted (Mallampati classification IV). A narrow-bored tracheostomy tube (speech cannula) was inserted. In the operating room, the tip of a 5.0 mm ID standard tube was inserted from the tracheostomy tube, and connected to a breathing circuit. Anesthesia was induced with inhalation of sevoflurane, followed by intravenous propofol, fentanyl, and rocuronium. Four anesthesiologists were required to intubate the trachea. One person held the tracheal tube placed in the tracheotomy tube. The second person performed jaw thrusting. The third person inserted the Glidescope to shift the transplanted tongue to the side. It was then possible for the forth anesthesiologist to manage to see the glottis using a fiberoptic bronchoscope, and a double-lumen tube (DLT) could be inserted to the trachea orally. Inserting a DLT over the fiberoptic bronchoscope is a blind method, but we felt that combined with a variety of tools such as video laryngoscope, the success rate in intubation will increase.

[Usefulness of ACUSON Freestyle (Siemens), Wireless Ultrasound System].

The ACUSON Freestyle, the world's first wireless ultrasound system, was released in April 2014. We assessed its usefulness, using it for central venous cannulation, spinal anesthesia, brachial plexus or obturator nerve block, and for the surgery of metastatic liver cancer as well as the spine. Generally, we could use it smoothly in all situations. Comparing with the conventional ultrasound system, the machine is big, heavy, with many buttons to operate. The main problem with the conventional ultrasound system is the wire connecting probe and the main system, which can interfere with procedures. With ACUSON Freestyle, we could perform the nerve block and the central venous cannulation more easily with little concern about contamination.

[Use of the i-gel for Tracheostomy in a Patient with Neck Deformity and Tracheal Stenosis].

We report a successful use of the i-gel for tracheostomy in a patient with severe neck deformity and tracheal stenosis. A 20-year-old man, 142 cm, 22 kg, was scheduled for tracheotomy. He had tracheal stenosis with hypoxemia, due to the pressure from the brachiocephalic artery, associated with severe progression of symptomatic scoliosis and thoracic deformity. Using a fiberoptic bronchoscope, we confirmed that there was no upper airway obstruction. After induction of anesthesia, facemask ventilation was easy. The i-gel was easily inserted, and fiberscope-aided tracheal intubation through the i-gel was attempted, but decided not to intubate the trachea, due to the degree of stenosis. Tracheostomy was performed, while a clear airway was maintained by the i-gel. We consider that the i-gel has a potential role for tracheostomy in a patient with neck deformity and tracheal stenosis.

[Anesthetic Management of a Patient with Corrected Transposition of Great Arteries for Cesarean Section].

A 30-year-old woman with corrected transposition of great arteries (c-TGA) was scheduled for elective cesarean section at 37 weeks of gestation. At previous cesarean section, she received general anesthesia for dyspnea and lower cardiac function by severe mitral regurgitation, with a pulmonary catheter inserted. In the current pregnancy, she had tricuspid regurgitation, but she had no signs of heart failure. Cardiac index (CI) and stroke volume variation (SVV) were monitored by the FloTrack, before induction of anesthesia. Because the CI was 3.6 l x min(-1) x m(-2), and the SVV was 18%, we decided to perform combined spinal epidural anesthesia. Epidural anesthesia was performed at L1-2, and spinal anesthesia was performed at L3-4. Hyperbaric 0.5% bupivacaine 2.0 ml with fentanyl 10 µg was given to the subarachnoid space. The total dose of phenylephrine administered was 150 µg, and the CI as well as the SVV were stable during surgery. Her postpartum couse was uneventful. Anesthetic management of c-TGA is discussed, and we should select anesthetic method carefully.

[Emergency Tracheal Intubation Using Airwayscope in a Patient with Hematoma after Thyroidectomy].

We report a case of emergency awake intubation using Airwayscope (AWS) in a patient with difficulty of the ventilation combined with severe neck swelling due to hematoma after thyroidectomy. A 28-year-old woman with thyroid tumor received, general anesthesia induced, easily with facemask ventilation and tracheal intubation. Her trachea was extubated after she had become awake. Several minutes later, sudden swelling of the neck was observed, and she lost her consciousness. Despite attempts at facemask ventilation, hypoxia with bradycardia was observed. We judged that insertion of the supraglottic airway or the needle cannulation of the cricothyroid membrane would be difficult reducing the chance of re-intubation. While we asked surgeons to prepare for emergency surgical tracheotomy, we attempted to intubate the trachea using the AWS under sedation. Despite difficulty in opening the mouth and swelling of the tongue, we managed to intubate the trachea. We consider that knowledge of difficult airway management (DAM) is necessary, but we must be flexible to judge which method should be used in each patient In addition we conclude that the AWS is useful for awake intubation.

[Combined Use of a Videolaryngoscope and a Transilluminating Device for Intubation with Two Difficult Airways].

Videolaryngoscope is useful in patients with difficult airways, but it may not be in some patients. We report the use of a lighted stylet to facilitate tracheal intubation in 2 patients in whom laryngoscopy with a videolaryngoscope was difficult. Case 1: A 52-year-old female with loose teeth and lockjaw presented for a scoliosis surgery under general anesthesia. Laryngoscopy using a blade 3 of a Glide-Scope® (Laerdal Medical Corporation, New York, NY, USA) videolaryngoscope (GVL) showed a Cormack-Lehanne grade 3 view. Bag mask ventilation was easily achieved. By using the Trachilight™ (Saturn Biomedical System Burnaby, BC, Canada) with the GVL, we could intubate the trachea succesfully. Case 2: A 16-year-old male with a history of difficult tracheal intubation due to a limited cervical spine movement presented for an external fixation of a femur under general anesthesia. After induction of anaesthesia, bag mask ventilation was easily achieved but the GVL laryngoscopy did not provide a good view of the glottis (Cormack-Lehanne grade 3). Combined use of the Trachilight™ with the GVL, facilitated tracheal intubation. The Trachilight™ is a recognized aid to facilitate trachal intubation but the device is now commercially not available. Neverthless, we believe that a lighted stylet is potentially useful for tracheal intubation when the view of the glottis with a videolaryngoscopy is not ideal.