The short-term efficacy of high flow nasal oxygen therapy on cardiovascular surgical patients: a randomized crossover trial

Background

Oxygen therapy after extubation in the intensive care unit (ICU) is essential in order to maintain adequate oxygenation, especially in patients who have undertaken cardiovascular surgery. A Venturi mask (VM) has been routinely used as an oxygen therapy in the ICU. Recently, however, the high flow nasal cannula (HFNC) has become available, and this device can deliver up to 60 L/min of humidified oxygen. The aim of this study is to evaluate the short-term efficacy between HFNC and VM in cardiovascular surgical patients.

Methods

Forty patients who underwent cardiovascular surgery were randomized to either protocol A (HFNC followed by VM) or protocol B (VM followed by HFNC). After 60-minutes of use with either device, arterial blood gas analysis was performed, and the PaO₂/FiO₂ ratio (PFR) was calculated. Simultaneously, physiological data (respiratory rate, heart rate, mean arterial pressure, continuous cardiac index, and mixed venous oxygen saturation) were recorded. During this procedure, FiO₂ and gas flow were maintained at a fixed rate. These variables were compared by using the paired t-test, and a p value < 0.05 was considered significant. All data were expressed as mean (standard deviation).

Results

Thirty-five patients (17 from protocol A and 18 from protocol B) were enrolled, and 5 patients were excluded from analysis in accordance with the exit criteria. PaO₂ was significantly higher in the HFNC group than in the VM group [101.7 (25.9) vs. 91.8 (23.0), mean difference 9.87 (18.5), 95% confidence interval 3.5 to 16.2, p = 0.003]. Moreover, PFR was significantly higher in the HFNC group than in the VM group [265.9 (81.4) vs. 238.7 (68.5), p = 0.002]. Moreover, PaCO₂ was significantly lower in the HFNC group than in the VM group [33.8 (3.5) vs. 34.7 (2.9), p = 0.033]. The respiratory rate was significantly lower in the HFNC group than in the VM group [18 (4) vs. 21 (4), p = 0.006], and no significant differences were seen in any of the other parameters.

Conclusions

Compared to VM, HFNC ameliorated oxygenation function and decreased patients’ effort in breathing. The hemodynamic state did not differ between HFNC and VM. Therefore, HFNC can be used safely in cardiovascular surgical patients.

Trial registration

This trial was registered with the UMIN Clinical Trials Registry (ID UMIN000016572).

Toward a Practical Impedimetric Biosensor: A Micro-Gap Parallel Plate Electrode Structure That Suppresses Unexpected Device-to-Device Variations

We propose a rational electrode design concept for affinity biosensors based on electrochemical impedance spectroscopy to substantially suppress unexpected device-to-device variations. On the basis that the uniformity of the current distribution affects the variation, a novel micro-gap parallel plate electrode (PPE) was developed, where two planar electrodes with edges covered with a SiO₂ layer were placed face to face. The structure provides a uniform current distribution over the planar electrode surface and maximizes the contribution of the planar electrode surface to sensing. For a comparative study, we also fabricated a micro-structured interdigitated electrode (IDE) that has been widely adopted for high-sensitivity measurement, although its current is highly concentrated on the electrode edge corner. Protein G (PrG) molecules were immobilized on both electrodes to prepare an immunoglobulin G (IgG) biosensor on which the specific binding of PrG-IgG can occur. We demonstrated that the IgG sensor with the PPE has small device-to-device variations, in strong contrast to the sensor with the IDE having large device-to-device variations. The results indicate that the current distribution on the electrode surface is important to fabricating electrochemical impedance spectroscopy biosensors with small device-to-device variations. Furthermore, it was found that the PPE allows ultrasensitive detection, that is, the sensor exhibited a linear range from 1 × 10^-13 to 1 × 10^-7 mol/L with a detection limit of 1 × 10^-14 mol/L, which is a record sensitivity at low concentrations for EIS-based IgG sensors.

PaO 2 / FiO 2 ratio responsiveness to prone positioning in intubated patients with severe COVID ‐19: a retrospective observational study

Aim

Prone positioning of coronavirus disease 2019 (COVID‐19) patients could improve oxygenation. However, clinical data on prone positioning of intubated COVID‐19 patients are limited. We investigated trends of PaO₂ / FiO₂ ratio values in patients during prone positioning to identify a predictive factor for early detection of patients requiring advanced therapeutic intervention such as extracorporeal membrane oxygenation (ECMO).

Methods

This retrospective, observational cohort study was undertaken between April 2020 and May 2021 in a tertiary referral hospital for COVID‐19 in Osaka, Japan. We included intubated adult COVID‐19 patients treated with prone positioning within the first 72 h of admission to the intensive care unit and followed them until hospital discharge or death. Primary outcomes were in‐hospital mortality and escalation of care to ECMO. We used unsupervised k‐means clustering modeling to categorize COVID‐19 patients by PaO₂ / FiO₂ ratio responsiveness to prone positioning.

Results

The final study cohort comprised 54 of 155 consecutive severe COVID‐19 patients. Three clusters were generated according to trends in PaO₂ / FiO₂ ratios during prone positioning (cluster A, n = 16; cluster B, n = 24; cluster C, n = 14). Baseline characteristics of all clusters were almost similar. Cluster A (no increase in PaO₂ / FiO₂ ratio during prone positioning) had a significantly higher proportion of patients placed on ECMO or who died (6/16, 37.5%). Numbers of patients with ECMO and with in‐hospital death were significantly different between the three groups (p = 0.017).

Conclusion

In Japanese patients intubated due to COVID‐19, clinicians should consider earlier escalation of treatment, such as facility transfer or ECMO, if the PaO₂ / FiO₂ ratio does not increase during initial prone positioning.

Multiple Cardiovascular Diseases or Risk Factors Increase the Severity of Coronavirus Disease 2019

BACKGROUND

This study aimed to determine whether disease severity varied according to whether coronavirus disease 2019 (COVID-19) patients had multiple or single cardiovascular diseases and risk factors (CVDRFs).Methods and Results:COVID-19 patients with single (n=281) or multiple (n=412) CVDRFs were included retrospectively. Multivariable logistic regression showed no significant difference in the risk of in-hospital death between groups, but patients with multiple CVDRFs had a significantly higher risk of acute respiratory distress syndrome (odds ratio: 1.75, 95% confidence interval: 1.09-2.81).

CONCLUSIONS

COVID-19 patients with multiple CVDRFs have a higher risk of complications than those with a single CDVRF.

[Efficacy of Transversus Abdominis and Rectus Sheath Blocks in Combination with Continuous Intravenous Fentanyl for Postoperative Analgesia of Laparoscopic Colectomy: A Retrospective Study]

BACKGROUND

Ultrasound-guided transversus ab- dominis plane (TAP) and rectus sheath (RS) blocks are peripheral nerve blocks that diminish somatic pain of the abdominal wall and are useful for postoperative analgesia. Here, we retrospectively compared the effi- cacy of ultrasound-guided TAP and RS blocks in com- bination with continuous intravenous fentanyl for postoperative analgesia of laparoscopic colectomy.

METHODS

The ethics committee of our institute ap- proved the study. In our hospital, postoperative analge- sia is performed with continuous intravenous fentanyl administration at three concentrations : 12.5, 18.75, and 31.25 μg · hr⁻¹. TAP and RS blocks were applied using 30-40 ml of 0.19-0.25% ropivacaine. We selected 43 patients who underwent laparoscopic colectomy from May to October 2015. We compared the fentanyl only group (F group, n=26) and block combination group (F+B group, n=17). Statistical analysis was performed with the Mann-Whitney U test P<0.05 was considered significant Results : Patient characteristics including age, height, body weight, duration of anesthesia, and surgery did not significantly differ between the two groups. The concentration of intravenous fentanyl was significantly lower in the F+B group than in the F group (F group : 19.5±8.4μg · hr⁻¹, F+B group : 14.7?4.9 μg · hr⁻¹, P=0.02). In the present study, TAP and RS blocks significantly reduced the dose of administered fentanyl. - Conclusions : Our findings suggest that a combina- tion of TAP and RS blocks lower the dose of continu- ous intravenous fentanyl needed, and may provide better postoperative analgesia after laparoscopic colec- tomy.

[A Case of Lethal Atypical Takotsubo Cardiomyopathy Detected by Sustained Ventricular Arrhythmia Just before Induction of General Anesthesia]

A 73 year-old female patient was scheduled for lumbar peritoneal shunt three weeks after subarachnoid hemorrhage. Before induction of general anesthesia, her ECG showed ventricular tachycardia (VT) without any complaints. Administration of lidocaine and direct current shocks were ineffective and VT continued. Operation was postponed and transthoracic echocardiography revealed diffuse hypokinesis. Emergent angiogram revealed midventricular ballooning with slight hypoki- nesis in basal and apical regions without significant coronary artery lesion. Atypical takotsubo cardiomyopathy was diagnosed. Intra aortic balloon pumping and continuous infusion of amiodaron and catecholamines were started, but her ventricular motion decreased. She died next morning. In this case, the physical/psychological stress before operation was con- sidered to be a trigger of the event. Although tako- tsubo cardiomyopathy is usually a transient disease, it must be kept in mind that an acute and lethal case with no response to any treatment like ours exists.

[Anesthetic Management of Acute Pulmonary Thrombus Trapped in a Patent Foramen Ovale Detected by Transesophageal Echocardiography]

We report a case of intracardiac thrombus detected by transesophageal echocardiography (TEE). A 61-year-old man with pulmonary embolism was trans- ferred to our hospital presenting with severe respira- tory distress. Emergency surgery was scheduled to remove the thrombus identified in the right atrium by transthoracic echocardiography (TEE). Four-chamber view TEE confirmed penetration of a patent foramen ovale (PFO) to the left atrium by a thrombus ; there was no thrombus in the right ventricle or pulmonary artery. Cardiopulmonary bypass was safely established without deep hypothermic circulatory arrest and the thrombus was removed uneventfully. Subsequent TEE confirmed the absence of the thrombus. In the present case, preoperative TEE was unable to reveal the thrombus trapped in the PFO. TEE is more sensitive in identifying precise information regarding the exis- tence of thrombi. Moreover, contrast echocardiography may help detect right-to-left shunting through a PFO.

[Anesthetic Management of a Pediatric Case of Blue Rubber Bleb Nevi Syndrome Combined with Small-intestinal Intussusception]

We report the anesthetic management of a pediatric case of blue rubber bleb nevi syndrome combined with small-intestinal intussusception. A 2-year-old girl was transferred to our hospital for small-intestinal intussusception. Emergent ablation of the upper gastrointestinal tract nevus under general anesthesia was planned. Given the presence of several nevi in the oral and pharyngeal space, we utilized the McGRATH MAC (McGRATH; Aircraft Medical Ltd, United Kingdom) laryngoscope for gentle and stress-free tracheal intubation. The venous line was kept patent preoperatively, and rapid-sequence intubation was performed with the McGRATH (size 2 pediatric blade). A 4.5-mm tracheal tube was inserted uneventfully under direct visualization. The trachea was observed and the tube maintained in a proper position with a bronchofiberscope. During the procedure, cuff volume was regulated to avoid excessive increase by upper gastrointestinal endoscope insertion. The girl was extubated in the operating room and showed no postoperative complications such as hemorrhage or hoarseness.

[Anesthetic Management of Video-assisted Left Upper Lobectomy in a Patient with Ischemic Heart Disease Using an Intraaortic Balloon Pump]

We report the successful anesthetic management of video-assisted left upper lobectomy in a patient with ischemic heart disease using an intra-aortic balloon pump (IABP). An 81-year-old man with severe ischemic heart disease was scheduled for partial lobectomy for suspected lung cancer under general anesthesia. Although he had severe ischemic heart disease, coronary intervention such as percutaneous cardiac intervention or coronary artery bypass grafting was impossible due to severe coronary stenosis. IABP was instituted through the femoral artery before inducing anesthesia. Tracheal intubation was performed with the McGRATH MAC videolaryngoscope to minimize stress. Surgery was performed uneventfully and the patient was transferred to the intensive care unit under sedation. IABP was removed three hours postoperatively. After confirming no ischemic or vital sign changes, he was extubated the next day. No complications resulting from the IABP were observed.

[Anesthetic Management of Simultaneous Right Lobectomy and Esophagectomy with a Double-lumen Tracheal Tube and Bronchial Blocker]

Anesthestic management with prolonged one-lung ventilation is difficult, especially when the patient continues smoking habit. Here, we report a successful one-lung ventilation and protection with combined use of double-lumen endotracheal tube and bronchial blocker. A 68-year-old man (height 153 cm; weight, 45 kg) was scheduled for simultaneous surgery of right lobectomy and esophagectomy. He kept smoking to the operation day. To protect the ventilated lung, we guided the bronchial lumen of the DLT to the left bronchus under fiberoptic bronchoscope (FOB) guide and inflated the bronchial cuff. Next, we inserted the bronchial blocker from the tracheal lumen of the DLT and inflated the cuff in the left bronchus under FOB guidance. We performed continuous suctioning of the right trachea via the inner lumen of BB. During the operation, non-negligible amount of blood and sputum was aspirated from the inner lumen of the BB. Furthermore, there was no visible blood inflow in the left bronchus. We could protect the ventilated lung with double cuff, i. e. bronchial cuff of DLT in the left bronchus and BB cuff in the right bronchus. Simultaneous operation was uneventfully performed and no oxygenation or ventilation trouble was observed during the operation.

[Anesthetic Management for Lobectomy in a Patient with Pulmonary Arterial Hypertension]

Pulmonary arterial hypertension (PAH) is a known risk factor of perioperative complications, but the risks for non-cardiac operations have not yet been examined sufficiently. We report a case of a right lower lobectomy in a patient with PAH. A 73-year-old woman with Sjögren's syndrome was scheduled for right lowr lobectomy for primary lung cancer under general anesthesia. She was diagnosed with symptomatic PAH (estimated mean pulmonary arterial pressure, 40 mmHg) and medicated with ambrisentan. After induction of general anesthesia with propofol and fentanyl, a pulmonary artery catheter was placed to measure pulmonary artery pressure. The Pp/Ps was roughly 0.4 and the pulmonary artery clamp elevated it to 0.5. Milrinone administration gradually improved the Pp/Ps to 0.3. To avoid pulmonary artery pressure elevation during emergence of anesthesia, continuous dexmedetomidine was administered. The double-lumen tracheal tube was extubated uneventfully with minimal elevation in pulmonary arterial pressure.

[Successful Resuscitation from Cardiac Arrest due to Pulmonary Artery Rupture Utilizing Cardiopulmonary Bypass]

We report a case of successful resuscitation from cardiac arrest due to pulmonary artery rupture utilizing cardiopulmonary bypass. A 79-year-old man was diagnosed with lung cancer; segment resection of the upper lung was scheduled under general anesthesia. Anesthesia was induced uneventfully and surgery began in the right lateral position. During lung resection, the pulmonary artery was ruptured and led to cardiac arrest with pulseless electrical activity. Astriction, volume overload, and hypertensive medication led to vital sign recovery. Percutaneous cardiopulmonary support was achieved with improvements in the blood flow of the femoral vein and artery. Yet, bleeding from the ruptured artery did not stop. Cardiopulmonary bypass with pulmonary artery blood removal and femoral artery blood transmission stopped the bleeding of the damaged part, leading to the repair of the artery. Rapid establishment of cardiopulmonary bypass may be useful in cases of pulmonary artery damage.

Persistent left superior vena cava with absent right superior vena cava detected during emergent coronary artery bypass grafting surgery

Although persistent left superior vena cava (PLSVC) itself is a common venous anomaly in congenital heart disease, PLSVC with absent right superior vena cava (RSVC) is a rare venous congenital malformation. Due to the lack of symptoms, this malformation is often detected fortuitously when patients undergo central venous catheter placement, pacemaker implantation, or open cardiac surgery. This particular venous malformation is rare, but clinicians in many fields should be well aware of its variations and management techniques to avoid complications. Anesthesiologists should know that patients with PLSVC rarely have absent RSVC. TEE was helpful in the diagnosis of PLSVC with absent RSVC during emergent surgery.

[A Case of Septic Shock Immediately following Cesarean Section]

Here we report a case of severe septic shock immediately following cesarean section. A pregnant woman with dichorionic diamniotic twins was diagnosed with preterm rupture of membranes (PROM). Ritodrine hydrochloride and betamethasone did not sufficiently relieve abdominal extension; emergency cesarean section was scheduled 4 days later, at 31 week 5 day gestation. The patient did not show any symptoms or laboratory data suggesting infection. Spinal anesthesia was initiated with 2.2 ml of 0.5% bupivacaine hydrochloride and fentanyl 10 μg at L3-4; sensory loss (T3) was confirmed. Epidural anesthesia at L1-2 was performed for postoperative pain control. Surgery proceeded uneventfully, but the first baby did not respond to neonatal CPR. One hour after surgery, the patient showed signs of shock and a fever of 40.9 degrees C. Catecholamine and antibiotics relieved her symptoms. Retrograde infection of Escherichia coli was attributed to fetal distress and septic shock. Early phase septic shock should be considered in pregnant women with PROM.

[Development of Takotsubo Cardiomyopathy during Recovery from General Anesthesia: A Case Report]

Takotsubo cardiomyopathy is a cardiac syndrome characterized by transient left ventricular dysfunction. A 61-year-old woman underwent laparoscopic cholecystectomy under general anesthesia. During recovery from general anesthesia, several arrhythmias occurred without cardiac collapse following desflurane discontinuation and sugammadex sodium administration. She had a chest pain after extubation, with ST segment elevation in leads aV(L) and V2-4. Emergency left ventricular angiogram revealed no significant coronary stenosis, and excessive contraction of the base and severe hypokinesis of the apex suggested Takotsubo cardiomyopathy. Sympathetic hyperactivity during acute recovery from anesthesia with desflurane discontinuation and muscle relaxant reversal with sugammadex sodium was considered the likely cause of Takotsubo cardiomyopathy.

Comparison of McGRATH MAC and Macintosh laryngoscopes for double-lumen endotracheal tube intubation by anesthesia residents: a prospective randomized clinical trial

STUDY OBJECTIVE

This study aimed to compare the utility of McGRATH MAC (McG) and Macintosh (McL) laryngoscopes for double-lumen endotracheal tube intubation in patients undergoing elective surgery.

DESIGN

Randomized clinical trial.

SETTING

Operating room.

PATIENTS

Fifty adult patients scheduled for elective surgery under 1-lung ventilation with American Society of Anesthesiologists physical status 1 to 3.

INTERVENTIONS

Double-lumen endotracheal tube intubation was performed with the McG (McG group; 25 patients) or conventional McL (McL group; 25 patients) laryngoscope by anesthesia residents.

MEASUREMENTS

The number of attempts to successful intubation, intubation time, percentage of glottis opening score, and subjective difficulty of laryngoscopy and tube passage through the glottis were assessed.

MAIN RESULTS

The total numbers of intubation attempts were 1 (McG group, 24 patients; McL group, 16 patients), 2 (McG group, 1 patient; McL group, 8 patients), and 3 (McG group, 0 patient; McL group, 1 patient), with significant differences between the two groups (P = .018). Intubation time was significantly shorter in the McG group compared with the McL group (McG: 17.1 ± 4.6 seconds vs McL: 20.8 ± 5.9 seconds, P = .026). The percentage of glottis opening score was significantly higher in the McG group compared with the McL group (McG: 88.4% ± 13.7% vs McL: 71.4% ± 20.4%, P = .004).

CONCLUSIONS

The McG demonstrated a better intubation profile compared with the McL, possibly due to its ease of use for double-lumen endotracheal tube intubation. Clinical Trial registry number: UMIN000014636.

[Rapid Sequence Intubation with the McGRATH MAC Videolaryngoscope in the Sitting Position for a Patient with Restricted Mouth Opening]

Here we report successful rapid-sequence inubation with the McGRATH MAC videolaryngscope (McGRATH) in the face to face sitting position for a patient with severe ileus and restricted mouse opening. A 46-year-old woman with advanced bladder cancer had developed ileus. Ileus tube and octreotide did not relieve her symptoms, and emergency colostomy was planned. Due to the invasion of cancer to the spine and interior of the pelvis, she could not keep supine position and always kept sitting position. We decided to perform rapid-sequence intubation in the sitting position. First an anesthesiologist stood at face to face position to the patients, and the second anesthesiologist kept the head of the patient from the cranial side. After thiamylal and fentanyl administration, cricoid pressure was applied by the third anesthesiologist. Under the guide of the McGRATH's monitor, we could successfully insert the 7.0 mm internal diameter tracheal tube with a stylet uneventfully in the face to face sitting position.

[Anesthetic Management of Right Lower Lobectomy in a Patient with Marfan Syndrome]

We report a case of partial lobectomy in a patient with Marfan syndrome. A 56-year-old woman with Marfan syndrome was scheduled for partial lobectomy for suspected lung cancer under general anesthesia. She underwent a Bentall operation and mitral valve replacement 10 months before and strict blood pressure management was required. After induction of general anesthesia with propofol and fentanyl, topical intratracheal lidocaine anesthesia was performed using the Pentax-AWS Airwayscope (AWS) for visualization, allowing for the Soft-tipped Tube Exchanger (TE-Soft) to be inserted into the trachea. Next, a double-lumen tracheal tube was uneventfully intubated via the TE-Soft with minimal change in vital signs. During the operation, pressure-controlled ventilation was performed to minimize the risk of pneumothorax. After the operation, under continuous administration of landiorol and dexmedetomidine, the double-lumen tracheal tube was extubated uneventfully. Strict airway and circulation management is needed for lung or vessel preservation in patients whose conditions are complicated by Marfan syndrome.

Laryngoscopy facilitates successful i-gel insertion by novice doctors: a prospective randomized controlled trial

BACKGROUND

This study investigated the hypothesis that the efficacy of insertion of the supraglottic device i-gel(®) (i-gel) can be improved by laryngoscopy and can provide better sealing pressure in anesthetized patients by novice doctors.

METHODS

Eighty-four adult patients were assigned to the laryngoscopy group (L group, 42 patients) or control group (i.e., conventional blind insertion; C group, 42 patients). Anesthesia was induced with propofol and remifentanil, and rocuronium 0.6-0.9 mg/kg was administered. The number of attempts until successful insertion, sealing pressure, vital sign changes upon insertion, and subjective difficulty of insertion by novice doctors were compared between the groups.

RESULTS

The total number of insertion attempts was one (L group 36 cases, C group 23 cases), two (L group 6 cases, C group 18 cases), and three (L group 0 case, C group 1 case), with significant differences between groups (P = 0.007). The sealing pressure was significantly higher in the L group than in the C group (L group 22.3 ± 2.6 cmH2O, C group 19.5 ± 2.7 cmH2O, P < 0.001). Vital sign changes (heart rate and blood pressure) did not differ between the two groups. The subjective difficulty of insertion was significantly lower in the L group than in the C group (L group 26.8 ± 11.8 mm, C group 47.0 ± 15.1 mm, P < 0.001). The incidence of postoperative pharyngeal pain was significantly lower in the L group than in the C group (P < 0.001), while the incidence of hoarseness did not differ between the two groups (P = 1.00).

CONCLUSION

Our results suggest that laryngoscopy facilitates i-gel insertion by novice doctors, as reflected in the rate of successful insertions, higher sealing pressure, and lower subjective difficulty of insertion in anesthetized patients.

Rapid-Sequence Intubation in the Left-Lateral Tilt Position in a Pregnant Woman with Premature Placental Abruption Utilizing a Videolaryngoscope

Case A 24-year-old pregnant woman was admitted to our hospital with decreased fetal heart rate. Obstetric examination revealed premature placental abruption; emergent caesarean section was planned under general anesthesia. On entering the operating room, the patient showed severe vital sign deterioration (blood pressure, 75/45 mm Hg; heart rate, 142 beats per minute). As left uterine displacement may worsen the premature placental abruption, the patient was placed in the left-lateral tilt position by rotating the operating table to release compression on the inferior vena cava by theuterus. To avoid circulatory collapse, rapid-sequence intubation was performed in this position. Tracheal intubation was performed with the Pentax-AWS Airwayscope (AWS videolaryngoscope, AWS; HOYA, Japan) to obtain a good laryngeal view and minimize stress from laryngoscopy. After sufficient oxygenation, 120 mg of thiopental was administered. A second anesthesiologist performed cricoid pressure and 50 mg of rocuronium was administered after confirming loss of consciousness. This was followed by insertion of the AWS with a thin intlock into the mouth. Tracheal intubation was performed uneventfully. Discussion Rapid-sequence intubation in the left-lateral tilted position with the AWS videolaryngoscope may be beneficial for pregnant women with vital sign deterioration.

[Successful Tracheal Intubation Using Videolaryngoscope in an Infant with Massive Tongue Swelling]

We report use of videolaryngoscope for difficult airway management in an infant with severe tongue swelling after laceration repair. A 3-month-old male infant was transferred to our hospital for respiratory difficulty. He could not open his mouth sufficiently, and the examination revealed massive swelling of the left side of the tongue. Emergent surgical repair of the tongue was scheduled, anticipating a difficult airway. The venous line was kept patent preoperatively, and 8% sevoflurane was administered maintaining spontaneous ventilation. We then inserted the Pentax Airway Scope with an infant-sized Intlock (AWS-I) from the right side of the mouth and obtained a good view at laryngoscopy. A 3.5-mm tracheal tube was passed uneventfully under the view of AWS-I. The AWS-I is useful for difficult airway management in infants, preserving spontaneous ventilation.

Effects of cigarette smoking on endurance performance levels of 16- to 19-year-old males

The purpose of this study was to explore the effects of cigarette smoking on the levels of endurance performance in teenagers. Longitudinal data of physical characteristics, smoking habits, exercise habits, and time records in both 1500-meter run and 10-kilometer run of 202 sixteen-to-nineteen-year-old male students were retrieved and analyzed retrospectively. The results showed that the performance levels of exercise-neversmokers in the 1500-meter run did improve as the subjects grew older, and that over the same period, the exercise-smokers did not improve but were able only to maintain their performance levels. The results of two way analysis of variance(ANOVA) indicated that smoking negatively and independently impacts how eighteen and nineteen-year-olds will perform in a 10-kilometer run. The reduced levels of endurance performance in the non-exercise smokers showed up in their results in the 10-kilometer run, and the diminished performance levels of the exercise-smokers were revealed in their 1500-meter run times. These results suggest that smokers obtain less benefits from training than non-smokers, and that we need to assess endurance performance levels among the young by paying careful attention to their smoking habits.

A cross-sectional population-based study on senile dementia in a rural city

All residents aged 65 or over in a rural city (n=5340) were studied with a self-administered questionnaire on psychiatric symptoms, physical health status, medical history, and environmental factors. After the screening, the clinical diagnosis of senile dementia was made by psychiatrists. The overall prevalence was 4.0% among responders staying at home (201/4969). The prevalence increased with age for both males and females and tended to be higher for females than males. The multilogistic analysis of the above variables showed that in the cerebrovascular type, stroke and inactive physical status might be risk factors for both gender groups. For the Alzheimer's type, age and inactive physical status might be risk factors. For overall dementia, age, stroke, and inactive physical status might be risk factors.

[Successful fiberoptic tracheal intubation via Cobra PLA in a patient with an epiglottic tumor]

A 59-year-old woman with an epiglottic tumor was scheduled for the total removal of the mass by laryngomicrosurgery. The patient had no preoperative respiratory symptoms. During the induction of anesthesia, the mask ventilation was easily accomplished; however, when rigid laryngoscopy was attempted, an epiglottic tumor prevented exposure of the vocal cords. After a size 3 Cobra PLA had been placed, a size 6.5 mm reinforced tube was threaded over a fiberoptic bronchoscope through the Cobra PLA into the trachea. Post-extubation course was uneventful. The Cobra PLA can be a good alternative supraglottic airway device allowing easy tracheal intubation for difficult airway.

[Three cases of acute pulmonary thromboembolism diagnosed by transesophageal echocardiography]

We report 3 cases of acute pulmonary thromboembolism (PTE) diagnosed by transesophageal echocardiography (TEE). In all these cases, cardiovascular state of the patient was unstable and therefore computerized tomography and catheterization of the pulmonary artery for diagnosis of PTE could not be performed. TEE was useful for diagnosis of acute PTE. All three patients passed away eventually and we had a difficult experience for treatment of acute PTE. We should take various measures against deep vein thrombosis for prevention of acute PTE.

A proposal for guideline for prevention of allergic occupational asthma in conformity with the globally harmonized system of classification and labelling of chemicals (GHS)

The use of chemical products to enhance and improve life is a widespread worldwide practice. Alongside the benefits of these products, there is also the potential of chemicals for adverse effects to people or the environment. As a result, a number of countries or organizations have developed laws or regulations over the years that require information to be prepared and transmitted to those using chemicals, through labels or Safety Data Sheets (SDS). Their differences are significant enough to result in different labels or SDS for the same product in different countries. In July 2003, United Nations (UN) recommended the globally harmonized system of classification and labelling of chemicals (GHS). We, special committee of Japanese Society of Occupational and Environmental Allergy proposed a guideline for prevention of allergic occupational asthma and sensitizers (n=60) causing occupational asthma or contact dermatitis in conformity with respiratory and skin sensitization criteria of GHS. We should propose these 60 sensitizers to the chemical industry association and governments to control, regulate and label them in each country.

[Epidural blood patch for intracranial hypotension with closed system in a Jehovah's Witness]

We report a case of treating intracranial hypotension with an epidural blood patch using closed system that allows blood collection and epidural injection without loss of continuity. The patient was a 34-year-old woman with severe headache for several months. The headache failed to respond to conservative management. By radioisotope cisternography, it was diagnosed as intracranial hypotension. Epidural blood patch was planned for intracranial hypotension. We used the method of epidural blood patch in a closed venous blood transfusion system to the epidural space, because she is a member of the Jehovah's Witness. Twenty five ml of blood was drawn into the syringe and injected into the epidural space with closed system. The patient was discharged home after 3 days with dramatically reduced symptons. Epidural blood patching with closed system is a safe, and effective procedure that is acceptable to a Jehovah's Witness.

Fetal arachnoid cyst of the quadrigeminal cistern in MRI and ultrasound

CASE

The authors report a fetus with an arachnoid cyst of the quadrigeminal cistern without hydrocephalus at 30 gestational weeks.

DISCUSSION AND CONCLUSION

We reviewed the literature and could find only 62 reported cases of arachnoid cyst of the quadrigeminal cistern. We present a case without hydrocephalus diagnosed by combining ultrasound (US) and magnetic resonance imaging (MRI). The fetus, born by normal delivery, was followed up and did not show hydrocephalus for 1 year. This combined prenatal study, which uses US and MRI, helps in dispensing proper counseling to parents and assists the gynecologist and the neurosurgeon in the pre- and postnatal management of this condition.

A novel diagnostic method for evaluation of vascular lesions in the digestive tract using infrared fluorescence endoscopy

BACKGROUND AND STUDY AIMS

We have developed an infrared fluorescence endoscope to evaluate gastrointestinal vascular lesions. Infrared endoscopy (IRE) after intravenous administration of indocyanine green (ICG) is used at present to examine vascular lesions such as esophageal varices. However, no previous study has compared the sensitivity of infrared fluorescence endoscopy (IRFE) with that of IRE. In this study, we compared the usefulness of IRFE and IRE.

PATIENTS AND METHODS

For IRFE we used an infrared endoscope equipped with excitation and barrier filters and an intensified charge-coupled device camera. In preliminary experiments, the observable tissue depth was assessed by wrapping increasing numbers of layers of commercially available pork around a syringe containing a uniform concentration of ICG or by changing the concentration of ICG in a syringe covered by a piece of pork of uniform thickness. In the clinical part of the study, ICG was administered intravenously at different concentrations to patients with esophageal varices and the resulting infrared fluorescent images were evaluated.

RESULTS

The preliminary experiments revealed that the depth of tissue that could be visualized was significantly greater in IRFE than it was in IRE (11.2 mm in IRFE vs. approximately 3.2 mm in IRE). Clear infrared fluorescence was obtained by IRFE at lower concentrations of ICG than the concentrations required to obtain clear images using IRE. In the clinical part of the study, clear infrared fluorescence was observed in a region where esophageal varices had been detected by conventional endoscopy when ICG was administered in doses of 0.005 mg/kg to 0.01 mg/kg, which was lower than the doses used in IRE.

CONCLUSIONS

Compared with conventional IRE, IRFE facilitated the observation of deeper layers, and esophageal varices were observed by IRFE following the intravenous administration of a markedly reduced dose of ICG. IRFE, in combining the characteristics of reflected infrared light and fluorescence, may be a useful novel procedure in the diagnosis of vascular lesions in the gastrointestinal tract.

Usefulness of Constructive Interference in Steady State (CISS) Imaging for the Diagnosis and Treatment of a Large Extradural Spinal Arachnoid Cyst

We present a rare case of a symptomatic large extradural arachnoid cyst extending from the lower thoracic to sacral region in a 12-year-old boy, who presented with the signs and symptoms of spinal cord compression over 4 years. Since the pedicle of the cyst could not be delineated using conventional magnetic resonance imaging (MRI), cine-mode MRI, and computed tomography scan, partial resection of the cyst was initially performed, which significantly improved motor function. After the first operation, a single pedicle was clearly demonstrated by 3D constructive interference in steady state (CISS) MRI. Thus, additional surgery aimed at closing the dural defect was performed to prevent future enlargement of the cyst. The operative findings were consistent with those of 3D CISS imaging. Clinical and radiological features of this lesion are discussed, focusing on the usefulness of 3D CISS MRI for preoperative evaluation, and especially for delineating the pedicle in cases of large extradural spinal arachnoid cysts.

Intraoperative thermal artery imaging of an EC-IC bypass in beagles with infrared camera with detectable wave-length band of 7-14 microm: possibilities as novel blood flow monitoring system

OBJECTIVE

In the past, the usefulness of thermal arterial imaging during coronary bypass surgery using an infrared camera has been reported by several investigators. The goal of this study is to apply this novel imaging system for intraoperative arterial imaging, as well as to develop new utilizations for a neurosurgical procedure.

MATERIALS

We have attempted real-time imaging of anastomotic and flow status in an external carotid-internal carotid artery (EC-IC) bypass surgery using a new-generation infrared camera (IRIS IV thermographic imaging system) in beagles. No contrast medium or radiation was used to obtain the images. The detectable wave-length band of the infrared lens was 7-14 microm. After completion of bypass monitoring, an additional teflon tube was inserted into a branch of the STA to inject physiological saline of different temperatures to see the changes in cortical images.

RESULTS

Anastomotic and flow status were clearly visualized throughout the operation without local surface cooling, which had been an inevitable procedure in coronary imaging to make a pronounced temperature difference between artery and adjacent tissue. In addition, cortical flow territory was visualized after injection of either cold or warm physiologic saline into the artery from an additionally inserted teflon tube into a branch of STA via bypass artery.

CONCLUSION

From the present experience, it is considered that infrared imaging using a detectable wave length band of 7-14 microm may be applicable to a wide variety of near surface lesions, providing a non-invasive functional angiography.

Basic study of an agent for reinforcement of near-infrared fluorescence on tumor tissue

BACKGROUND AND AIMS

An indocyanine green derivative (ICG-sulfo-OSu) and agents for reinforcement of infrared fluorescence, which can be used as an infrared fluorescent labeling substance suitable for detection of microlesions by an IR fluorescence endoscope, have been developed. The study aims were to confirm the ability of a reinforcement agent, as well as imaging processing, to intensify fluorescence from the labeled antibody on immunohistochemical staining.

SUBJECTS AND METHODS

ICG-sulfo-OSu-labeled MUC1 antibody and an IR fluorescence imaging system were employed in the present study. Paraffin sections of gastric cancer were stained with anti-MUC1 antibody by the avidin-biotinylated peroxidase complex method. Among the positive specimens, three cases were used for IR imaging analysis. Octylglucoside was used as a reinforcement agent.

RESULTS

The incubation of paraffin sections with ICG-sulfo-OSu-labeled MUC1 antibody resulted in positive staining of the tumor sites by an IR fluorescence imaging system, and the intensity of fluorescence was increased depending on the concentration of octylglucoside and grade of imaging processing.

CONCLUSION

A reinforcement agent, and image processing, intensify a labeled antibody excitable by infrared fluorescence in tumor sections and can generate a strong enough fluorescent signal to detect small cancers when examined with an infrared fluorescence endoscope.

Intraoperative direct neuroendoscopic observation of the aqueduct in Dandy-Walker malformation

A 3-month-old female infant with Dandy-Walker malformation manifesting as hydrocephalus was treated successfully by only ventriculoperitoneal shunting. A flexible neuroendoscope was used intraoperatively to confirm the patency of the aqueduct, i.e. communication of the ventricular system and the cyst in the posterior fossa. Direct confirmation of the patency of the aqueduct and cyst communication is valuable to select the shunt procedure in the treatment of Dandy-Walker malformation.

Greater trunk muscle torque reduces postmenopausal bone loss at the spine independently of age, body size, and vitamin D receptor genotype in Japanese women

Bone mineral density (BMD) is affected by muscle strength. Recently, vitamin D receptor (VDR) genotype was reported to affect muscle strength as well as BMD in Caucasian women. The aim of this study was to evaluate independent effects of muscle strength of the trunk on BMD at the spine and its change over time in Japanese women. We followed 119 healthy postmenopausal women for 4 years and determined the change in BMD at the spine by dual energy X-ray absorptiometry. Isometric peak torque and isokinetic concentric and eccentric peak torque of the trunk flexors and extensors were measured. The VDR genotype was determined by the PCR-RFLP method based on Apa I and Taq I endonuclease digestions defining the absence/existence of the restriction sites as A/a and T/t, respectively. The subjects were 60.1 +/- 6.6 years old, had 0.808 +/- 0.159 g/cm2 of BMD at baseline. The mean annual change in BMD (delta BMD) was -5.6 +/- 10.4 mg/cm2 during the follow-up period. The VDR genotype, defined by Taq I enzyme, significantly related to BMD at baseline and delta BMD showing that the subjects with genotype TT had the lowest BMD at baseline and lost bone most rapidly. However, its effect on muscle strength was not significant. All the trunk muscle strength indices showed significant positive effects on delta BMD, that is, the effects in increasing the gain and reducing the loss of BMD, after controlling for the effects of age, body size and the VDR genotype. The eccentric trunk extensor torque had a significant positive effect on delta BMD in a dose-dependent manner. The effect of this torque was the greatest among all the muscle indices. The net effect of the trunk extensor torque on delta BMD was greater than that of the VDR genotype. The trunk muscle strength was suggested to affect BMD change independently of age, body size, and the VDR genotype. Exercise programs to increase the strength of the trunk muscles would be beneficial for the prevention of osteoporosis regardless of the VDR genotypes.

(1)H double-quantum filtered MR imaging of joints tissues: bound water specific imaging of tendons, ligaments and cartilage

The (1)H double-quantum filtered (DQF) NMR and DQF MRI is applied to the joint tissues of rabbits for selective visualization of tendons, menisci and articular cartilage. The (1)H DQF NMR selectively filters double-quantum coherence arising from the (1)H dipolar interaction of the "bound" water in these tissues. The double-quantum creation time dependency of the DQF signal intensity is determined by the molecular environment of the "bound" water. Therefore, each tissue has a unique creation time at which the DQF signal reaches its maximum intensity, tau(max) (Achilles tendon: 0.46 +/- 0.02 ms, patella: 0.55 +/- 0.8 ms, anterior cruciate ligament: 0.60 +/- 0.05 ms, meniscus: 0.78 +/- 0.02 ms, skin: 0.81 +/- 0.07 ms). We have presented the creation-time-contrasted DQF images of the meniscus, patella, foot, and knee joint. Compared with conventional T(2)*-weighted gradient-echo (GRE) MR images, tendons, ligaments, menisci, and articular cartilage were more clearly seen in the DQF MR images. All these tissues were distinctly discriminated from each other by their creation times. DQF MR images of foot and knee joints can selectively demonstrated tendons, ligaments, and cartilage, which make it easier to understand the complicated anatomic structure of joints. Because the DQF NMR signal intensity and tau(max) are sensitive to the order structure of the "bound" water, it might be possible to introduce the creation-time dependent-contrast of (1)H DQF MR images as a new tool for analyzing the changes in the ordered structure of the tissue.

Inhibitory effect of T-614 on tumor necrosis factor-alpha induced cytokine production and nuclear factor-kappaB activation in cultured human synovial cells

OBJECTIVE

To investigate the mechanism of the immunosuppressive effect of T-614 [N-(3-formylamino-4-oxo-6-phenoxy-4H-chromen-7-yl)methanesulfonamide], a new antirheumatic drug whose clinical efficacy has been determined for the treatment of patients with rheumatoid arthritis (RA).

METHODS

RA synovial fibroblast-like cells were cultured with tumor necrosis factor-alpha (TNF-alpha, 10 ng/ml) in the presence or absence of T-614. After incubation, cytokine production was measured by ELISA. Expression of interleukin 6 (IL-6) and IL-8 mRNA was examined by real-time quantitative reverse transcriptase-polymerase chain reaction analysis and TNF-alpha induced nuclear factor-kappaB (NF-kappaB) activation was observed using immunostaining with an antibody against NF-kappaB p65.

RESULTS

T-614 suppressed TNF-alpha induced production of IL-6, IL-8, and monocyte chemoattractant protein 1, and also reduced the accumulation of IL-6 and IL-8 mRNA in a concentration dependent manner. T-614 interfered with the TNF-alpha induced translocation of NF-kappaB to the nucleus from the cytoplasm.

CONCLUSION

Inhibition of NF-kappaB activation and transcription of proinflammatory cytokines by T-614 contributes to its clinical antirheumatic effect.

Urocortin expression in synovium of patients with rheumatoid arthritis and osteoarthritis: relation to inflammatory activity

Peripherally produced CRH acts as a local auto/paracrine proinflammatory agent. Urocortin is a new member of the CRH family that acts through the family of CRH receptors. In this study, we demonstrated that the expression of urocortin mRNA in synovia of patients with rheumatoid arthritis was greater than that of patients with osteoarthritis. Also, we detected urocortin and CRH receptor immunoreactivity in the synovial lining cell layer, subsynovial stromal cells, blood vessel endothelial cells, and mononuclear inflammatory cells from the joints of rheumatoid arthritis and osteoarthritis patients. The expression of immunoreactive urocortin was significantly greater in rheumatoid arthritis than osteoarthritis (P < 0.0001) and correlated with the extent of inflammatory infiltrate. CRH receptor immunoreactivity was strong in mononuclear inflammatory cells of rheumatoid arthritis synovia. Urocortin stimulated IL-1beta and IL-6 secretion by human peripheral blood mononuclear cells in vitro. These findings suggest that, like CRH, urocortin is present in peripheral inflammatory sites, such as rheumatoid synovium, and acts as an immune-inflammatory mediator.

Detection of human gastric cancer in resected specimens using a novel infrared fluorescent anti-human carcinoembryonic antigen antibody with an infrared fluorescence endoscope in vitro

BACKGROUND AND STUDY AIMS

An indocyanine green derivative (ICG-sulfo-OSu) that can be used as an infrared fluorescent labeling substance suitable for detecting microlesions with an infrared fluorescence endoscope has been developed. The aims of the present study were to develop an infrared fluorescence endoscope and to demonstrate its usefulness in detecting cancerous tissue using an antibody coupled with ICG-sulfo-OSu.

MATERIALS AND METHODS

ICG-sulfo-OSu-labeled mouse anti-human carcinoembryonic antigen (CEA) antibody and an infrared fluorescence endoscope were used in this study. Biopsy specimens of gastric cancer were stained with anti-CEA antibody using the avidin-biotinylated peroxidase complex method. The positive specimens used for the infrared imaging analysis were freshly resected stomachs from three patients.

RESULTS

Treatment of freshly resected stomach specimens with ICG-sulfo-OSu-labeled-anti-CEA antibody complex resulted in positive staining of the tumor sites on infrared fluorescence endoscopy, and the infrared fluorescent images correlated well with the tumor sites.

CONCLUSIONS

An anti-CEA antibody with affinity for cancerous lesions and labeled with ICG-sulfo-OSu can therefore be imaged using this infrared fluorescence endoscope. Specific antibodies tagged with ICG-sulfo-OSu can label cancer cells and can generate a strong enough fluorescent signal to detect small cancers when examined with an infrared fluorescence endoscope.

Effect of platinum coordination complex (PtCx) on citrate uptake by rat renal brush border membrane vesicles (BBMV): cisplatin-intoxicated rats

Platinosis with severe dermatitis and/or asthma is broadly defined as the effects of soluble platinum salts on people exposed to them occupationally. Platinum coordination complexes are widely used in the treatment of a variety of solid tumors. However, the clinical use of cisplatin, the most useful agent, is limited by the development of nephrotoxicity. Thus, an accidental exposure to soluble platinum at a high dose in platinum refineries and pharmaceutical factories could induce occupational nephrotoxicity. Urinary citrate is freely filtered at the glomerulus, and its reabsorption in the proximal tubule is the major determinant of the rate of renal excretion. In our previous studies, we found that the preincubation of rat renal brush border membrane vesicles (BBMV) with cisplatin and carboplatin, a second-generation platinum coordination complex, significantly inhibited the citrate uptake compared with that of the control BBMV. In this study, we performed in vivo experiments in cisplatin-intoxicated rats to elucidate the toxic mechanism of cisplatin. And our results showed that the citrate uptake was significantly inhibited in cisplatin-intoxicated rats at 1 min compared with that of control rats.