Anesthesia Patient Safety: Next Steps to Improve Worldwide Perioperative Safety by 2030.

Patient safety is a core principle of anesthesia care worldwide. The specialty of anesthesiology has been a leader in medicine for the past half century in pursuing patient safety research and implementing standards of care and systematic improvements in processes of care. Together, these efforts have dramatically reduced patient harm associated with anesthesia. However, improved anesthesia patient safety has not been uniformly obtained worldwide. There are unique differences in patient safety outcomes between countries and regions in the world. These differences are often related to factors such as availability, support, and use of health care resources, trained personnel, patient safety outcome data collection efforts, standards of care, and cultures of safety and teamwork in health care facilities. This article provides insights from national anesthesia society leaders from 13 countries around the world. The countries they represent are diverse geographically and in health care resources. The authors share their countries' current and future initiatives in anesthesia patient safety. Ten major patient safety issues are common to these countries, with several of these focused on the importance of extending initiatives into the full perioperative as well as intraoperative environments. These issues may be used by anesthesia leaders around the globe to direct collaborative efforts to improve the safety of patients undergoing surgery and anesthesia in the coming decade.

Tribute to Dr. Takuo Aoyagi, inventor of pulse oximetry.

INTRODUCTION: Dr. Takuo Aoyagi invented pulse oximetry in 1974. Pulse oximeters are widely used worldwide, most recently making headlines during the COVID-19 pandemic. Dr. Aoyagi passed away on April 18, 2020, aware of the significance of his invention, but still actively searching for the theory that would take his invention to new heights. METHOD: Many people who knew Dr. Aoyagi, or knew of him and his invention, agreed to participate in this tribute to his work. The authors, from Japan and around the world, represent all aspects of the development of medical devices, including scientists and engineers, clinicians, academics, business people, and clinical practitioners. RESULTS: While the idea of pulse oximetry originated in Japan, device development lagged in Japan due to a lack of business, clinical, and academic interest. Awareness of the importance of anesthesia safety in the US, due to academic foresight and media attention, in combination with excellence in technological innovation, led to widespread use of pulse oximetry around the world. CONCLUSION: Dr. Aoyagi's final wish was to find a theory of pulse oximetry. We hope this tribute to him and his invention will inspire a new generation of scientists, clinicians, and related organizations to secure the foundation of the theory.

[Safety and efficacy of midazolam in children under mechanical ventilation in the intensive care unit].

BACKGROUND: The use of midazolam for children was approved in March, 2010. Since the efficacy and safety data of midazolam used in children, excluding low-birth-weight infants and newborns, for "sedation under artificial respiration in intensive care units" were quite limited, a post-marketing survey was carried out to confirm the validity of the established dosage and administration. METHODS: A consecutive enrollment method was adopted. Based on the data of 153 patients collected from 8 institutes, efficacy and safety profiles were analyzed. RESULTS: Among the 149 patients included in the safety analysis set, 6 adverse reactions were reported in 6 patients. The incidence of adverse events was 4.0% (6/149). Reported adverse reactions included depressed level of consciousness: 1 event, delirium: 1 event, psychomotor hyperactivity: 1 event, hypotension: 2 events, and blood pressure increase: 1 event. Serious adverse drug reaction (ADR) reported in this survey was depressed level of consciousness. This ADR resolved on the following day after the treatment with flumazenil. Paradoxical reactions were reported in 1 patient, and tolerance was reported in 2 patients. The efficacy rate was 96.5% (138/143). CONCLUSIONS: No additional safety issues (status of adverse reactions, status of adverse events, status of serious adverse events, etc.) and efficacy issue were manifest in the patients treated with the dosage and administration method established at the approval of the drug.

[Case of thoracoabdominal stent graft with postoperative paralysis which showed dramatic recovery after re-institution of spinal drainage].

A 62-year-old man underwent stent graft insertion for thoracoabdominal aneurysm. We inserted a spinal drainage catheter at L3-4 and started drainage at 10 cmH2O at the beginning of surgery. Intravenous naloxone was started from the beginning of the operation. Intraoperative course was uneventful, and postoperatively no neurological symptoms/signs were noted. The next day, 90 minutes after removal of the drainage catheter, sensory loss and muscle weakness of bilateral lower limbs developed. A drainage catheter was reinserted, and muscle weakness of the right lower limb recovered after 115 minutes, and sensory loss of left lower limb recovered after 260 minutes. There was no muscle weakness or paralysis after 300 minutes. The drainage was continued for the next 48 hours and removed without subsequent neurological symptoms and the patient was discharged eight days after the operation.

Changes in the characteristics of patients with latex allergy from 1999 to 2014.

OBJECTIVES: We conducted a multicenter study using the same questionnaire in 1999 and 2014 to investigate changes in the characteristics of patients with latex allergy. METHODS: We mailed questionnaires on latex allergy to hospitals in Japan that were members of the Japanese Latex Allergy Society. RESULTS: We compared the 25 responses received in 2014 and the 81 responses received in 1999. With regard to the age distribution, the number of patients with latex allergy in their 20s declined significantly from 1999 to 2014 (P=0.004). The largest proportion of latex allergy cases was observed among those aged <10 years. The incidence of cases caused by medical rubber gloves decreased significantly (P=0.004). Moreover, latex-fruit syndrome increased from 15% to 40% (P=0.006). CONCLUSIONS: Our findings indicate that the frequency of occurrence of latex allergy in people in their 20s decreased from 1999 to 2014. The largest proportion of latex allergy cases was observed among those aged <10 years. Future measures to protect children are required.

Multiwavelength pulse oximetry: theory for the future.

BACKGROUND: As the use of pulse oximeters increases, the needs for higher performance and wider applicability of pulse oximetry have increased. To realize the full potential of pulse oximetry, it is indispensable to increase the number of optical wavelengths. To develop a multiwavelength oximetry system, a physical theory of pulse oximetry must be constructed. In addition, a theory for quantitative measurement of optical absorption in an optical scatterer, such as in living tissue, remains a difficult theoretical and practical aspect of this problem. METHODS: We adopted Schuster's theory of radiation through a foggy atmosphere for a basis of theory of pulse oximetry. We considered three factors affecting pulse oximetry: the optics, the tissue, and the venous blood. RESULTS: We derived a physical theoretical formula of pulse oximetry. The theory was confirmed with a full SO2 range experiment. Based on the theory, the three-wavelength method eliminated the effect of tissue and improved the accuracy of Spo2. The five-wavelength method eliminated the effect of venous blood and improved motion artifact elimination. CONCLUSIONS: Our theory of multiwavelength pulse oximetry can be expected to be useful for solving almost all problems in pulse oximetry such as accuracy, motion artifact, low-pulse amplitude, response delay, and errors using reflection oximetry which will expand the application of pulse oximetry. Our theory is probably a rare case of success in solving the difficult problem of quantifying optical density of a substance embedded in an optically scattering medium.

[Preoperative evaluation in children].

It is important to evaluate medical history and to examine physical findings for preventing the complication during perioperative period. The communication among the medical staffs, and the explanation to the patients and family are also important. A different approach from the adult is necessary for infant's preoperative assessment. The problems encountered in specific disease for children were described.

Prolonged nitric oxide inhalation during recovery from chronic hypoxia does not decrease nitric oxide-dependent relaxation in pulmonary arteries.

STUDY OBJECTIVE: To investigate the effects of long-term nitric oxide (NO) inhalation on the recovery process of right ventricular hypertrophy (RVH) and functional alterations in the NO-cyclic guanosine monophosphate (cGMP) relaxation pathway in rat conduit pulmonary arteries (PAs) in established chronic hypoxic pulmonary hypertension. MATERIALS AND METHODS: A total of 35 rats were exposed to chronic hypobaric hypoxia (380 mm Hg, 10% oxygen), and 39 rats were exposed to air for 10 days. Both groups were then exposed to 3 or 10 days of NO 10 ppm, NO 40 ppm, or air (control groups for each NO concentration), resulting in a total of 16 groups. Acetylcholine- and sodium nitroprusside (SNP)-induced relaxation were evaluated in precontracted PA rings. RVH was assessed by heart weight ratio of right ventricle to left ventricle plus septum. RESULTS: NO inhalation had no effect on either the regression of RVH or the recovery process of impaired relaxation induced by acetylcholine or SNP in a endothelium-intact hypertensive conduit extrapulmonary artery or intrapulmonary artery (IPA). In a normal endothelium-intact conduit IPA, 40 ppm NO inhalation for 10 days partially augmented SNP-induced relaxation, but not that induced by acetylcholine. CONCLUSION: Continuous NO inhalation did not affect the regression process of either established RVH or the impaired endogenous NO-cGMP relaxation cascade in a conduit PA in rats during the recovery period after chronic hypoxia.

Cardiac output measurement by pulse dye densitometry using three wavelengths.

OBJECTIVES: Pulse dye densitometry (PDD), based on the principles of pulse oximetry and dye-dilution technique, is a less invasive method of measuring cardiac output (CO). We have developed prototype equipment to measure CO in pediatric patients using this technique. The purpose of our study was to evaluate the accuracy of this new PDD system using three wavelengths for pediatric application by comparing measurement with an ultrasound flowmeter. DESIGN: Laboratory investigation. SETTING: Hospital physiology research laboratory. SUBJECTS: A total of 15 young piglets weighing approximately 10 kg each. INTERVENTIONS: Measurement of CO by PDD was performed using general anesthesia. Indocyanine green, 0.2 mg/kg, was administered intravenously, and CO was calculated from the dye dilution curve obtained by the PDD system. The ultrasound flowmeter probe was placed on the ascending aorta in the animal, and CO was simultaneously calculated. MEASUREMENTS AND MAIN RESULTS: The two CO values, simultaneously obtained by the ultrasound flowmeter and PDD, were compared during various hemodynamic states. The bias between the CO measured by the ultrasound flowmeter and the CO measured by the PDD system using the reflection-type probe at the central site was 33.8 mL/min and the precision was 293.4 mL/min, indicating that CO measured by PDD had a good correlation with measurements obtained with the ultrasonic method. CONCLUSION: We measured CO in young piglets at an acceptable level of bias and precision using a prototype PDD device. CO measurement by this new PDD system using three wavelengths can be useful and beneficial for critically ill infants and children. It is simple to perform, requiring an injection of dye into a peripheral intravenous catheter, and it will provide a less invasive bedside measurement of CO.

Pressure-flow relationship and longitudinal distribution of pulmonary vascular resistance in heartworm-infected dogs.

The pressure-flow relationships and the longitudinal distributions of pulmonary vascular resistance in normal and heartworm-infected (HWI) dogs were compared in an isolated, blood perfused preparation. The pulmonary circulation was partitioned into pulmonary arterial, middle, and venous segment based on the concept of a five element lumped model. The pulmonary arterial pressure-flow relationships were found to be non-linear and convex to the pressure axis in both normal and HWI lungs. The pressure-flow relationships of the pulmonary arterial and venous segment were linear and these slopes in the HWI lungs were significantly higher than the normal lungs. The pressure gradient of the middle segment was increased as flow increased at lower flow range, however, it was not increased during higher perfusion range in both lungs. At higher flow, the pressure gradient of the middle segment in the HWI lungs was significantly higher than the normal lungs. These results suggest that the ohmic resistance was almost equal to the sum of the two slopes of the pressure-flow relationships of the pulmonary arterial and venous segment because the pressure gradient of the middle segment was not altered as flow increased during higher perfusion rate. Because the slopes of the pressure-flow relationships of the pulmonary arterial and venous segment were increased with heartworm infection, the ohmic resistance of HWI lungs would be higher than normal lungs. The intercept pressure on the pressure axis of the linear portion of the pulmonary arterial pressure-flow relationship, a critical closing pressure, was regarded as pressure gradient of the middle segment during higher perfusing rate because the intercept pressures of pressure-flow relationships of pulmonary arterial and venous segment were almost equal to zero. Therefore, the critical closing pressure of HWI lungs would be higher than normal lungs. The pulmonary hypertension of filariasis appears to be due to an increase in ohmic resistance and elevated critical closing pressure.

New method of chest compression for infants in a single rescuer situation: thumb-index finger technique.

We introduce a new method of external chest compression (ECC), an essential part of cardiopulmonary resuscitation, using a thumb and index finger method (TIFM) on infants, and compares, this with two standard methods of the two finger method (TFM) and the two-thumb encircling hands method (TTEM). Sixty trained PALS (Pediatric Advanced Life Support) providers were randomly assigned into three groups and provided one-rescuer ECC for a period of five continuous minutes. Results without coaching or feedback were recorded on a recording CPR simulator (Laerdal, Inc). ECC was performed according to the BLS recommendations of the International Liaison Committee on Resuscitation (ILCOR). The quality of ECC in the TFM group deviated considerably from guideline recommendations. The same parameters in the TTEM and new TIFM groups during this study were in accordance with the parameters recommended by the guidelines. Thus, our new TIFM technique of chest compression, in infants was shown to be better than the currently TFM, especially for achieving adequate compression depth and avoiding fatigue, and is equally as effective as the TTEM. We propose this new method (TIFM) should be considered as the method of choice in single rescuer situations.

A novel mainstream capnometer system for non-intubated pediatric patients requiring oxygen administration.

Capnometer has been widely used as a respiratory monitor. Stable carbon dioxide (CO(2)) monitoring of non-intubated patient is especially problematic due to the frequent occurrence of tube obstruction and it could be even more difficult when oxygen is being administered. Oxygen is often administered by an oxygen mask or oxygen nasal cannula; however there are some problems with these methods. For oxygen masks, it is necessary to provide high-flow oxygen to prevent rebreathing of exhaled CO(2), and as for oxygen nasal cannula, it is incapable of increasing the oxygen concentration and patient may feel uncomfortable during oxygen administration because it could dry nasal mucous. To solve these problems, we developed a novel mainstream capnometer system, which provides stable monitoring of exhaled CO(2) while administering oxygen. This capnometer system has a mask with an opening large enough to facilitate the observation of patient's nose and mouth and the procedures such as daily oral care. Furthermore, the outer rim of the mask is designed to effectively retain oxygen flow without causing rebreathing.

Pediatric anesthesia practice and training in Japan: a survey.

BACKGROUND: Pediatric anesthesia in Japan is in the developing stage. The aim of this study was to review pediatric anesthesia training in Japan and to discuss the future prospects for this field. METHODS: We sent questionnaires to assess current pediatric anesthetic practice and training to all 106 university hospitals [UHs; response rate, 66% (70/106)] and all 17 children's hospitals [CHs; response rate, 87.5% (15/17)] in Japan. We also sent questionnaires to assess attitudes towards pediatric anesthetic training, to all 280 representatives of the Japanese Society of Anesthesiologists [JSA; response rate, 57.9% (162/280)]. RESULTS: The hospital survey revealed the number of pediatric anesthesia cases encountered in 15 CHs (25,009 cases) to be almost equivalent to that in 70 UHs (29,031 cases). In 19 of these UHs, there were no newborn surgical cases. Forty-nine UHs reported that no special training program existed for pediatric anesthesia, and only five UHs mandated training at CHs. Sixty-six percent of the representative JSA members considered it premature for pediatric anesthesia to become a subspecialty, but 87% considered experience in pediatric anesthesia mandatory for anesthesia board qualification. CONCLUSIONS: This survey revealed that although pediatric anesthesia training is considered mandatory, university hospitals lack adequate numbers of pediatric cases and children's hospitals suffer from a shortage of staff positions and anesthesiologists, and hence are unable to satisfy this demand. Most representative members of our society consider it too early to subspecialize pediatric anesthesia in Japan.

Manifestation of mirror syndrome after fetoscopic laser photocoagulation in severe twin-twin transfusion syndrome.

Mirror syndrome is a preeclampsia-like disease first described in a case of severe hydrops fetalis caused by rhesus isoimmunization, later reported in some cases of nonimmunological fetal hydrops. Twin-twin transfusion syndrome (TTTS) is a severe complication associated with monochorionic pregnancies, in particular, severe TTTS with one hydropic fetus leading to a poor prognosis. We report here a case of mirror syndrome that occurred after selective fetoscopic laser photocoagulation in severe TTTS at 24 weeks' gestation.

Brain tissue oxygenation index measured by near infrared spatially resolved spectroscopy agreed with jugular bulb oxygen saturation in normal pediatric brain: a pilot study.

OBJECTIVES: This observational, prospective pediatric human study was performed to determine the agreement between brain tissue oxygenation indices (TOI) measured by near infrared spatially resolved spectroscopy and jugular bulb oxygen saturation values (SjO(2)). METHODS: Five cardiac patients without neurological impairment who were admitted into the critical care unit after open-heart surgery with jugular bulb venous catheters were enrolled. Their mean age was 8.6 months and mean body weight was 6.7 kg. Simultaneous measurements of brain TOI using NIR0-300 (Hamamatsu Photonics, Hamamatsu City, Japan) and SjO(2) values from blood samples were recorded. RESULTS: The TOI range was 59+/-9% and the SjO(2) range was 58+/-17%. The correlation coefficient R was 0.64 (p=0.11; n=14). Bland-Altman plotting revealed a bias of -3.4%, and precision of 7.2% (n=14). Intra-class correlation reliability analysis showed kappa of 0.55. CONCLUSION: Statistically, brain TOI was in reasonable agreement with SjO(2) in pediatric patients with normal brain within the measurement range from 50 to 70%.