Andrew Bowdle

Psychedelic effects of ketamine in healthy volunteers. Relationship to steady-state plasma concentrations

Background Ketamine has been associated with a unique spectrum of subjective “psychedelic” effects in patients emerging from anesthesia. This study quantified these effects of ketamine and related them to steady‐state plasma concentrations. Methods Ketamine or saline was administered in a single‐blinded crossover protocol to 10 psychiatrically healthy volunteers using computer‐assisted continuous infusion. A stepwise series of target plasma concentrations, 0, 50, 100, 150, and 200 ng/ml were maintained for 30 min each. After 20 min at each step, the volunteers completed a visual analog (VAS) rating of 13 symptom scales. Peripheral venous plasma ketamine concentrations were determined after 28 min at each step. One hour after discontinuation of the infusion, a psychological inventory, the hallucinogen rating scale, was completed. Results The relation of mean ketamine plasma concentrations to the target concentrations was highly linear, with a correlation coefficient of R = 0.997 (P = 0.0027). Ketamine produced dose‐related psychedelic effects. The relation between steady‐state ketamine plasma concentration and VAS scores was highly linear for all VAS items, with linear regression coefficients ranging from R = 0.93 to 0.99 (P < 0.024 to P <0.0005). Hallucinogen rating scale scores were similar to those found in a previous study with psychedelic doses of N,N‐dimethyltryptamine, an illicit LSD‐25‐like drug. Conclusions Subanesthetic doses of ketamine produce psychedelic effects in healthy volunteers. The relation between steady‐state venous plasma ketamine concentrations and effects is highly linear between 50 and 200 ng/ml.

Clinical and economic effects of pulmonary artery catheterization in nonemergent coronary artery bypass graft surgery

OBJECTIVE To examine the association between use of pulmonary artery catheterization with hospital outcomes and costs in nonemergent coronary artery bypass graft (CABG) surgery. DESIGN Retrospective cohort study. SETTING Fifty-six community-based hospitals in 26 states. PARTICIPANTS A total of 13,907 patients undergoing nonemergent CABG surgery between January 1, 1997, and December 31, 1997. MEASUREMENTS AND MAIN RESULTS Discharge abstracts for each patient were examined. Stratified and multivariate analyses were used to assess the impact of pulmonary artery catheters (PACs) on in-hospital mortality, length of stay in the intensive care unit, total length of stay, and hospital costs. Outcomes were adjusted for patient demographic factors, hospital characteristics, and hospital volume of PAC use in the year of analysis. Fifty-eight percent of the patients received a PAC. After adjustment, the relative risk of in-hospital mortality was 2.10 for the PAC group compared with the patients who did not receive a PAC (95% confidence interval [CI], 1.40 to 3.14; p < 0.001). The mortality risk was significantly higher in hospitals with the lowest third of PAC use (odds ratio, 3.35; 95% CI, 1.74 to 6.47; p < 0.001) and not significantly increased in the highest two thirds of users (odds ratio, 1.62; 95% CI, 0.99 to 2.66; p = 0.09). Days spent in critical care were similar; however, total length of hospital stay was 0.26 days longer in the PAC group (p < 0.001). Hospital costs were

A System for Anesthesia Drug Administration Using Barcode Technology: The Codonics Safe Label System and Smart Anesthesia Manager.

1,402 higher in the PAC group. CONCLUSION In the setting of nonemergent CABG surgery, pulmonary artery catheterization was associated with an increased risk of in-hospital mortality, greater length of stay, and higher total costs, particularly in hospitals with low volume of PAC use.

Percutaneous Coronary Sinus Catheterization for Minimally Invasive Cardiac Surgery—More Questions Than Answers?

BACKGROUND:Many anesthetic drug errors result from vial or syringe swaps. Scanning the barcodes on vials before drug preparation, creating syringe labels that include barcodes, and scanning the syringe label barcodes before drug administration may help to prevent errors. In contrast, making syringe labels by hand that comply with the recommendations of regulatory agencies and standards-setting bodies is tedious and time consuming. A computerized system that uses vial barcodes and generates barcoded syringe labels could address both safety issues and labeling recommendations. METHODS:We measured compliance of syringe labels in multiple operating rooms (ORs) with the recommendations of regulatory agencies and standards-setting bodies before and after the introduction of the Codonics Safe Label System (SLS). The Codonics SLS was then combined with Smart Anesthesia Manager software to create an anesthesia barcode drug administration system, which allowed us to measure the rate of scanning syringe label barcodes at the time of drug administration in 2 cardiothoracic ORs before and after introducing a coffee card incentive. Twelve attending cardiothoracic anesthesiologists and the OR satellite pharmacy participated. RESULTS:The use of the Codonics SLS drug labeling system resulted in >75% compliant syringe labels (95% confidence interval, 75%–98%). All syringe labels made using the Codonics SLS system were compliant. The average rate of scanning barcodes on syringe labels using Smart Anesthesia Manager was 25% (730 of 2976) over 13 weeks but increased to 58% (956 of 1645) over 8 weeks after introduction of a simple (coffee card) incentive (P < 0.001). CONCLUSIONS:An anesthesia barcode drug administration system resulted in a moderate rate of scanning syringe label barcodes at the time of drug administration. Further, adaptation of the system will be required to achieve a higher utilization rate.

Ultrasound Identification of the Guidewire in the Brachiocephalic Vein for the Prevention of Inadvertent Arterial Catheterization During Internal Jugular Central Venous Catheter Placement.

VARIETY OF cardiac operations are being performed now through small incisions or thoracoscopic ports that ay not allow for the direct placement of a coronary sinus atheter for the administration of retrograde cardioplegia. In ome centers, specially designed coronary sinus catheters are eing placed percutaneously by the anesthesiologist. Minimally nvasive cardiac surgery is not new although the techniques and he equipment continue to evolve. In 1998, this Journal pubished an article titled “Coronary Sinus Catheterization Made asy for Port-Access Minimally Invasive Cardiac Surgery.”1 espite the interest in this technique in the late 90s, it is not in idespread use today. In this issue, Lebon et al reported on heir experience placing 95 percutaneous coronary sinus cathters from the right internal jugular vein for minimally invasive ardiac surgery. By using transesophageal echocardiographic uidance for engaging the coronary sinus and fluoroscopy for dvancing the catheter in the coronary sinus, they attained a uccess rate of 87%, as judged by attaining a pressure in the oronary sinus 30 mmHg during cardioplegia administration. ailure occurred for a variety of reasons; the most common eason was displacement of the catheter from the coronary inus during surgery. The mean total procedure time was 16 4 minutes. They encountered 1 complication, a small, conned disruption in the coronary sinus identified by extravasaion of contrast agent, which was not clinically significant. There are several issues raised by this report that the authors nd thought provoking. They are the following: 1. What is the optimal depth for retrograde catheter position? The experience described in this report is consistent with the private practice experience of 2 of the authors (G.S.M. and L.G.S.) in the placement of 500 percutaneous coronary sinus catheters for minimally invasive cardiac surgery. The present authors’ technique for positioning the catheter closely matches that of Lebon et al, including an effort to position the catheter relatively deeply within the coronary sinus.

Hypertriglyceridemia, Lipemia, and Elevated Liver Enzymes Associated With Prolonged Propofol Anesthesia for Craniotomy

BACKGROUND:Imaging the guidewire with ultrasonography in the internal jugular vein during central venous catheterization often is used to verify proper guidewire placement and to aid in prevention of inadvertent arterial catheterization. It is known, however, that inadvertent arterial catheterization can occur despite imaging the guidewire in the internal jugular vein because the guidewire may continue through the far wall of the internal jugular vein and into an adjacent artery. We propose confirmation of the guidewire in the brachiocephalic vein with ultrasonography as a more reliable method of confirming proper guidewire placement. METHODS:A prospective feasibility study of 200 adult cardiothoracic surgery patients undergoing internal jugular vein catheterization was performed to determine whether the guidewire could be imaged with ultrasonography in the brachiocephalic vein. The guidewire was imaged in the internal jugular vein in a short-axis view, and the transducer was then angled caudally under the clavicle, following the guidewire into the brachiocephalic vein. RESULTS:The right internal jugular vein was catheterized in 193 patients and the left internal jugular in 7 patients. The brachiocephalic vein was successfully imaged in all but 2 patients. In 3 patients, the guidewire could not be clearly identified in the brachiocephalic vein because of interference from the leads of a heart rhythm device (pacemaker or defibrillator) or preexisting catheter. In 2 patients, the guidewire was not seen initially in the brachiocephalic vein because of coiling in the internal jugular vein, and in 1 patient because of the guidewire passing into the right subclavian vein, but all 3 were subsequently imaged in the brachiocephalic vein after repositioning. CONCLUSIONS:During internal jugular vein catheterization, the brachiocephalic vein was imaged with ultrasonography in 99% of patients (the lower 1-sided 99% confidence limit is 96%). The guidewire was imaged in the brachiocephalic vein in all cases except when leads from a heart rhythm device caused interference, although in some patients with leads, the guidewire could be imaged without difficulty. The absence of the guidewire from the brachiocephalic vein was indicative of a malpositioned guidewire.

Relative costs of anesthesiologist prepared, hospital pharmacy prepared and outsourced anesthesia drugs

: Lipemic blood was noted in the surgical field by a neurosurgeon after 12.5 hours of anesthesia consisting of infusions of propofol (total dose, 14,956 mcg) and remifentanil (total dose, 25,091 mcg). For most of that time, the rate of propofol was 120-160 mcg·kg-1·min-1 and never exceeded 160 mcg·kg-1·min-1. Lipemia was confirmed by allowing a sample of the patients blood to settle in a syringe. The triglyceride concentration was 15.8 mmol/L. There was no metabolic acidosis or other indications of propofol infusion syndrome. Postoperatively, liver enzymes were elevated (peak aspartate aminotransferase, 420 units/L) but returned to nearly normal within 5 days. The patient recovered from surgery uneventfully. Reports of intraoperative lipemia during propofol anesthesia are very rare but raise concerns about the safety of prolonged propofol infusion.

Airway anatomy of airsim high-fidelity simulator

BACKGROUND Anesthesia drugs can be prepared by anesthesia providers, hospital pharmacies or outsourcing facilities. The decision whether to outsource all or some anesthesia drugs is challenging since the costs associated with different anesthesia drug preparation methods remain poorly described. METHODS The costs associated with preparation of 8 commonly used anesthesia drugs were analyzed using a budget impact analysis for 4 different syringe preparation strategies: (1) all drugs prepared by anesthesiologist, (2) drugs prepared by anesthesiologist and hospital pharmacy, (3) drugs prepared by anesthesiologist and outsourcing facility, and (4) all drugs prepared by outsourcing facility. MAIN RESULTS A strategy combining anesthesiologist and hospital pharmacy prepared drugs was associated with the lowest estimated annual cost in the base-case budget impact analysis with an annual cost of

CASE 3—2013

225 592, which was lower than other strategies by a margin of greater than

A pulmonary artery catheter does not affect the intravascular electrocardiogram from the 'air aspiration introducer sheath'

86 000. CONCLUSION A combination of anesthesiologist and hospital pharmacy prepared drugs resulted in the lowest annual cost in the budget impact analysis. However, the cost of drugs prepared by an outsourcing facility maybe lower if the capital investment needed for the establishment and maintenance of the US Pharmacopeial Convention Chapter <797> compliant facility is included in the budget impact analysis.