Innovation in sedation and analgesia training.

PURPOSE OF REVIEW: We reviewed evidence of recent innovations in sedation education and discuss experiences with sedation training in Taiwan. RECENT FINDINGS: Current Status of Sedation Training: Didactic training and supervised clinical mentoring are common methods of sedation training. Although training course designed by professional societies to meet individual hospital credentialing requirements, the course content and training expectations vary and are likely inadequate to non-anesthesiologist sedation practitioners. Less Common Forms of Sedation Training: These include screen-based simulation, high-fidelity manikin-based simulation. Screen-based simulation sedation training is popular, convenient, and relatively inexpensive. Although there are numerous courses available, course content has not been standardized. High-fidelity simulation has been accepted to improve knowledge, self-confidence, awareness of emergency, crisis resource management, and teamwork, but it is costly, time intensive, and requires expertise in using simulation equipment. Although screen-based training is attractive and convenient, there is no evidence to suggest that it can replace high-fidelity simulation. Another recently developed education modality is virtual reality simulation. It has gained recent popularity as an immersive approach to medical training, but minimal content has been developed for sedation training. Beyond training, several other potential innovations may improve sedation effectiveness and patient safety. These include adherence to practice guidelines established by professional organizations, utilization of a pre-procedure sedation checklist, interpreting capnography, and implementation of real-time bedside drug displays that provide predictions of concentrations and their associated effects. SUMMARY: Effective sedation education and training, especially for nonanesthesiologists, is essential to improve patient safety for procedural sedation. Several innovative approaches have been proposed and are relatively early in their development and implementation. Further studies designed to assess the impact of these new training modalities on patient safety and outcomes are warranted.

An iatrogenic complication of radial artery cannulation.

Here, we report a potentially serious iatrogenic complication of arterial cannulation, and discuss the management and prevention of accidental arterial cannula transection. A 73-year-old man suffered from accidental cannula transection after removal of a radial arterial cannula. Three-dimensional computed tomography was used to confirm and locate the retained catheter. Surgical exploration was performed to remove the retained catheter, and the operation was completed smoothly without residual sequelae. Iatrogenic transection of arterial cannula is rarely reported. However, we should always be aware of the possibility of occurrence of this severe complication. We provide some recommendations for its management and ways to prevent its occurrence.

Ultrasonic cardiac output monitor provides accurate measurement of cardiac output in recipients after liver transplantation.

BACKGROUND: The ultrasonic cardiac output monitor (USCOM; USCOM Pty. Ltd., Sydney, NSW, Australia) has been accepted as a noninvasive device for measuring cardiac function in various clinical conditions. The present study aimed at comparing the accuracy of this device with that of the thermodilution technique in recipients in the early postoperative period after liver transplantation. METHODS: Fifteen mechanically ventilated patients were studied on the first postoperative day after liver transplantation. We compared the left-sided and right-sided cardiac output (CO) determined by USCOM with that obtained from the thermodilution technique with a pulmonary artery catheter every 8 hours in the intensive care unit. Each patient received a total of four paired measurements. Bland-Altman analysis was used for bias and precision testing. The CO measured by USCOM and the thermodilution method were considered interchangeable if the limits of agreement lay within +/- 1 L per minute or 20% of the mean CO. RESULTS: Forty-eight paired left-sided CO measurements were obtained from 12 patients. Three patients were excluded due to unacceptable signals. Comparison of these two techniques revealed a bias of 0.13 L per minute and limits of agreement at -0.65 L and 0.92 L per minute. Fifty-six paired right-sided CO measurements were obtained from 14 patients with one patient excluded due to an unobtainable optimal signal. A bias of 0.11 L per minute with limits of agreement at -0.51 L and 0.72 L per minute were found for these two techniques. CONCLUSION: This is the first study to evaluate the accuracy of USCOM in the post-liver transplant setting. This device is accurate in measuring CO in liver transplant recipients postoperatively. Possible risks of arrhythmia, infection and pulmonary artery rupture can be avoided because of its noninvasive nature. USCOM should be considered as an alternative in hemodynamic monitoring after liver transplantation.

Accuracy of a new body length-based formula for predicting tracheal tube size in Chinese children.

BACKGROUND: Variations in body weight and length (height) in children in the same age group have increased. Traditional age-based formulas often fail to predict the correct endotracheal tube (ETT) size. In our previous study, we devised a new length-based formula as follows: ETT internal diameter (ID) (mm) = 2 + (body length in cm/30). The current study was undertaken to assess the accuracy of this formula in Chinese children. METHODS: The ETT size was selected according to this length-based formula for 336 children who required tracheal intubation during general anesthesia. Incidences of tube change were recorded. Statistical analysis was performed using the chi-square test for differences in accuracy between age groups and body length groups. RESULTS: The length-based formula predicted a suitable ETT size in 277 (82.4%) of 336 subjects. There were 59 (17.6%) reintubations. Only 5 (1.49%) patients needed two tube changes when the correct ETT size was 1 mm larger or smaller than predicted. There were no statistically significant differences between age groups or length groups. CONCLUSIONS: The length-based formula ID (mm) = 2 + body length in cm/30 has high accuracy in predicting the appropriate ETT size in Chinese children.

Reliability of a new ultrasonic cardiac output monitor in recipients of living donor liver transplantation.

The ultrasonic cardiac output monitor (USCOM) is a new Doppler device for noninvasive hemodynamic monitoring. The aim of this prospective nonrandomized study was to test the feasibility, perioperative reliability, and clinical applicability of using USCOM as an alternative to pulmonary artery catheterization in recipients of living donor liver transplantation. Thirteen patients scheduled to receive living donor liver transplants were initially recruited. Three were subsequently excluded prior to the commencement of surgery because of technical difficulties in obtaining diagnostic-quality images with USCOM. Ten patients proceeded to be studied. Cardiac output measurements by thermodilution and USCOM were compared at 30-minute intervals throughout the procedure and at 10 specific procedural reference points during the surgery when hemodynamic changes were most likely to be observed. The data were analyzed with Lin's concordance coefficient and Bland-Altman analysis. Two hundred ninety paired cardiac output values were obtained from the 10 patients. The concordance between both methods was excellent in 8 patients and satisfactory in 2. Bland-Altman analysis of all data produced a mean bias of - 0.02 L/minute for USCOM, and the 95% limits of agreement were -1.06 to +1.10 L/minute. Further analysis of the 10 reference time points showed minimal bias and high levels of agreement between the methods. We conclude that USCOM provides an accurate and noninvasive method for cardiac output measurement during liver transplantation. It may therefore represent an alternative to pulmonary artery catheter placement with consequent reduction in patient's risk and morbidity associated with catheterization. Liver Transpl 14:1029-1037, 2008. (c) 2008 AASLD.

Protection against large-volume regurgitated fluid aspiration by the ProSeal laryngeal mask airway.

The ProSeal laryngeal mask airway (PLMA) is designed to protect the airway from regurgitated fluid. However, successful channeling of large volumes of regurgitated fluid by PLMA is rarely reported. This case report states that a large volume of regurgitated fluid was successfully channeled by a PLMA. The patient was a healthy 43-year-old male, properly fasted, undergoing transurethral cystolithotomy under general anesthesia with a correctly-placed PLMA. Unexpectedly, a large volume of regurgitated fluid (> 500 mL) spurted out from the PLMA esophageal drainage tube 2 hours after surgery. Careful gastric decompression was performed and airway toilet showed no evidence of aspiration of gastric contents. An endotracheal tube was then placed in lieu of the PLMA for airway maintenance. By the end of surgery, 1300 mL of fluid was drained through the gastric tube. Extubation was smooth and the patient had an uneventful recovery. Further radiological examination revealed the existence of an unrecognized vesicorectal fistula, which allowed the cystoscopic irrigation fluid to escape to the GI tract, resulting in massive gastric regurgitation. The patient underwent fistula repair a week later and was discharged without further difficulty. This is a unique clinical case report to show PLMA can be effective in preventing aspiration when massive passive regurgitation occurs. Strategies in the management of massive regurgitation during PLMA use are discussed.

Delayed onset of sevoflurane-induced juvenile malignant hyperthermia after second exposure.

Malignant hyperthermia (MH) is a rare condition consisting of increased temperature and rigidity with mild to fulminant manifestation during anesthesia. Sevoflurane was thought to be a less potent triggering agent of MH; however, in literature review, the onset of MH after exposure to sevoflurane may be associated with calcium release from the sarcoplasmic reticulum. We present here a case of rarely-seen delayed MH induced by an inhalation agent of low-inducing probability, sevoflurane, after the second exposure to which within a short period of time. The patient was a five years old boy who received sevoflurane anesthesia for repeat orthopedic surgery within two days. Gradual elevation in heart rate, abrupt hypercarbia and hyperthermia were observed 90 min after induction. Dantrolene was administrated immediately with effective therapeutic response. Eventually, the patient recovered without any complication as an aftermath. Gradually elevated heart rate during the second exposure to sevoflurane was the atypical sign in the episode of MH in this case. One plausible explanation for the development of delayed onset of MH is the latent effect of the volatile anesthetic on the skeletal muscles. Therefore, it is worth noting for the anesthesiologists to recognize the possibility of an atypical MH and be alert for the possible occurrence of MH during routine anesthetic practice.