The comparison of predictive performance in bispectral index prediction during target effect-site controlled infusion of propofol using different blood effect-site equilibration rate constants in the same pharmacokinetic model / 대한마취과학회지

BACKGROUND: Blood-brain equilibration rate constant (k(e0)) is derived from either pharmacokinetic and pharmacodynamic modeling (k(e0_model)) or a model-independent observed time to peak effect (k(e0_tpeak)). Performance in bispectral index (BIS) prediction was compared between k(e0_model) and k(e0_tpeak) for microemulsion or long chain triglyceride (LCT) propofol. METHODS: Time to peak effect (t(peak), time to a maximally reduced BIS value) of microemulsion propofol after an intravenous bolus (1 mg/kg) was measured in 100 patients (group A(micro)). An observed t(peak) of 1.6 min for LCT propofol was obtained from an earlier study. Another 40 patients received a target controlled infusions of microemulsion propofol (k(e0_model) = 0.187/min, group B(micro) = 20) or LCT propofol (k(e0_model) = 0.26/min, group B(LCT) = 20) and remifentanil. The k(e0_tpeak)'s in group B(micro) and B(LCT) were calculated using the observed t(peak) value obtained from group A(micro) and 1.6 min, respectively. Effect-site concentrations of propofol were recalculated using the amounts of propofol infused over time and k(e0_tpeak)'s. Predicted BIS values calculated by sigmoid Emax equations with k(e0_model) and k(e0_tpeak) were compared with observed BIS values during induction and emergence for both formulations of propofol. RESULTS: Observed t(peak) of microemulsion propofol was 1.68 min. The median performance errors of BIS in group B(micro) were -1.83% (-24.8 to 18.9, k(e0_model)) and -2.42% (-26.1 to 36.2, k(e0_tpeak)), while 8.01% (-20.5 to 30.1, k(e0_model)) and 7.37% (-27.0 to 49.1, k(e0_tpeak)) in group B(LCT). The median absolute performance errors of BIS in group B(micro) were 11.87% (2.2-31.1k(e0_model)) and 14.38% (-0.6 to 44.6, k(e0_tpeak)), while 17.31% (5.54-36.0, k(e0_model)) and 18.28% (-0.1 to 56.0, k(e0_tpeak)) in group B(LCT). CONCLUSIONS: The k(e0_model) showed better performance in BIS prediction than the k(e0_tpeak).

Is the Spinous Process of T7 Usually at the Same Level as the Inferior Tips of the Scapulae?

OBJECTIVE: Appropriate placement of thoracic epidural catheter provides an adequate postoperative analgesia in chest and upper abdominal surgery. Usually, when thoracic epidural puncture is performed, both scapular lower tips and the thoracic (T)7 spinous process is assumed to be at the same horizontal level. The aim of this study is to identify the thoracic epidural puncture in the sitting position, with the neck flexed and arms crossed, may change the relationship between the thoracic vertebrae and the scapular lower tips. METHODS: One hundred patients with postoperative patient controlled epidural analgesia using thoracic epidural catheters were enrolled. It is presumed that the both scapular lower tips and T7 spinous process is at the equal level when performing thoracic epidural puncture. The actual insertion level of the Tuohy needle was examined by radiography when the patient was in the sitting position. RESULTS: Out of 100 patients, there were 62% that were in the same level as the scapular lower tips and T7 spinous process. However, 1% of the patients leveled at T4, 1% at T5, 25% at T6, 18% at T8, and 1% at T9. CONCLUSION: When performing the thoracic epidural puncture under the sitting position, the relationship of the T7 and the scapular lower tips may change. The change of position of scapular lower tips varied among T6.82+/-0.70. Therefore, to be precise, it is advised to utilize C-arm guide when epidural puncture is carried out.

Sedation and general anesthesia outside of the operating room

BACKGROUND: The aim of this study is to evaluate the status and adverse events of anesthesiologist-administered sedation and general anesthesia, outside of the operating room. METHODS: Patients undergoing sedation and general anesthesia, outside of the operating room, were retrospectively reviewed, during the study period from March to October of 2011. The patient's characteristics, primary diagnosis for the procedure, procedures performed outside of the operating room, adverse events associated with sedation and anesthesia, sedatives/anesthetic agents, and anesthetic time, were all assessed. RESULTS: A total of 429 patient's submitted data on 44 sedation/401 general anesthesia were encountered, during the study period. The range of age varied from 2 months to 83 yrs. Most common primary diagnosis for the procedure, during sedation or general anesthesia, was vascular or neurologic problem, respectively. The most frequently used sedatives or analgesics were propofol alone, during sedation (45%) and propofol with remifentanil, during general anesthesia (60%), respectively. Adverse events occurred in 32%, during sedation and 29%, during general anesthesia. Bradycardia occurred in 16% of sedation and hypotension occurred in 15% of general anesthesia. CONCLUSIONS: Our data suggest that the sedation/general anesthesia for procedures, outside of the operating room, have been performed in a complex situation, various location, and wide age groups. Adequate monitoring, sufficient anesthesia support, including skilled staff and emergency equipments, and appropriate drug for each procedure are needed for the patient's safety.

Anesthetic considerations during heart-lung transplantation in a patient with an unresectable pulmonary artery sarcoma / 대한마취과학회지

No abstract available.