Shantale Cyr

Reduced cerebral oxygen saturation during thoracic surgery predicts early postoperative cognitive dysfunction.

BACKGROUND The objective of this prospective study is to determine cognitive dysfunction after thoracic surgery. METHODS Seventy-six patients undergoing thoracic surgery with single-lung ventilation (SLV) of an expected duration of >45 min were enrolled. Monitoring consisted of standard clinical parameters and absolute oximetry (S(ct)O(2)). The Mini-Mental State Exam (MMSE) test was used to assess cognitive function before operation and at 3 and 24 h after operation. Data were analysed using Spearman correlation test; risks for cognitive dysfunction were expressed as odds ratios. P<0.05 and data are presented as median (interquartile range). RESULTS One patient was excluded from the study. S(ct)O(2) during SLV decreased to critical values of <65%, 60%, and 55% in 40 (53%), 15 (20%), and 5 patients (7%), respectively. Twenty-two patients (29%) had a decrease of MMSE>2 points 3 h after surgery, eight patients (10%) had a decrease of MMSE>2 points 24 h after surgery. Postoperative cognitive dysfunction correlated at r(2)=0.272, 0.285, 0.297 with patient exposure times to S(ct)O(2)<65% (P=0.018), <60% (P=0.013), <55% (P=0.010), respectively. The odds ratios of developing early cognitive dysfunction ranged from 2.03 (95% CI: 0.74-5.59) for a short (<5 min) exposure to S(ct)O(2)<65% to a maximum of 9.56 (95% CI: 1.75-52.13) when S(ct)O(2) was <60% for more than 30 min. CONCLUSIONS Early cognitive dysfunction after thoracic surgery with SLV is positively related to intraoperative decline of S(ct)O(2).

Transversus abdominal plane block for postoperative analgesia: a systematic review and meta-analysis of randomized-controlled trials.

PurposeThe transversus abdominal plane (TAP) block has been described as an effective pain control technique after abdominal surgery. We performed a systematic review and meta-analysis of randomized-controlled trials (RCTs) to account for the increasing number of TAP block studies appearing in the literature. The primary outcome we examined was the effect of TAP block on the postoperative pain score at six, 12, and 24 hr. The secondary outcome was 24-hr morphine consumption.SourceWe searched the United States National Library of Medicine database, the Excerpta Medica database, and the Cochrane Central Register of Controlled Clinical Studies and identified RCTs focusing on the analgesic efficacy of TAP block compared with a control group [i.e., placebo, epidural analgesia, intrathecal morphine (ITM), and ilioinguinal nerve block after abdominal surgery]. Meta-analyses were performed on postoperative pain scores at rest at six, 12, and 24 hr (visual analogue scale, 0-10) and on 24-hr opioid consumption.Principal findingsIn the 51 trials identified, compared with placebo, TAP block reduced the VAS for pain at six hours by 1.4 (95% confidence interval [CI], −1.9 to −0.8; P < 0.001), at 12 hr by 2.0 (95% CI, −2.7 to −1.4; P < 0.001), and at 24 hr by 1.2 (95% CI, −1.6 to −0.8; P < 0.001). Similarly, compared with placebo, TAP block reduced morphine consumption at 24 hr after surgery (mean difference, −14.7 mg; 95% CI, −18.4 to −11.0; P < 0.001). We observed this reduction in pain scores and morphine consumption in the TAP block group after gynecological surgery, appendectomy, inguinal surgery, bariatric surgery, and urological surgery. Nevertheless, separate analysis of the studies comparing ITM with TAP block revealed that ITM seemed to have a greater analgesic efficacy.ConclusionsThe TAP block can play an important role in the management of pain after abdominal surgery by reducing both pain scores and 24-hr morphine consumption. It may have particular utility when neuraxial techniques or opioids are contraindicated.RésuméObjectifLe bloc dans le plan du muscle transverse de l’abdomen (ou TAP bloc) a été décrit comme une technique efficace de contrôle de la douleur après une chirurgie abdominale. Nous avons réalisé une revue systématique et une méta-analyse des études randomisées contrôlées (ERC) pour faire un état des lieux du nombre croissant d’études sur le TAP bloc qui s’ajoutent à la littérature. Le critère d’évaluation principal était l’effet d’un TAP bloc sur les scores de douleur postopératoire à six, 12 et 24 h. Le critère d’évaluation secondaire était la consommation de morphine à 24 h.SourceNous avons effectué des recherches dans la base de données de la Bibliothèque nationale américaine de médecine (United States National Library of Medicine) ainsi que dans le Registre central Cochrane des études cliniques contrôlées (Cochrane Central Register of Controlled Clinical Studies). Nous avons ensuite identifié les ERC se concentrant sur l’efficacité analgésique des TAP blocs par rapport à un groupe témoin [c.-à-d. placebo, analgésie péridurale, morphine intrathécale (MIT) et bloc nerveux ilio-inguinal] après une chirurgie abdominale. Des méta-analyses ont été réalisées en examinant les scores de douleur postopératoire au repos à six, 12 et 24 h (échelle visuelle analogique [EVA], 0-10) et la consommation d’opioïdes sur une période de 24 h.Constatations principalesParmi les 51 études identifiées, par rapport à un placebo, le TAP bloc a réduit le score de douleur de 1,4 sur l’EVA après six heures (intervalle de confiance [IC] 95 %, −1,9 à −0,8; P < 0,001), de 2,0 après 12 h (IC 95 %, −2,7 à −1,4; P < 0,001) et de 1,2 après 24 h (IC 95 %, −1,6 à −0,8; P < 0,001). De la même façon, par rapport au placebo, le TAP bloc a réduit la consommation de morphine à 24 h après la chirurgie (différence moyenne, −14,7 mg; IC 95 %, −18,4 à −11,0; P < 0,001). Nous avons observé cette réduction en matière de scores de douleur et de consommation de morphine dans le groupe TAP bloc après des chirurgies gynécologiques, des appendicectomies, des chirurgies inguinales, des chirurgies bariatriques et des chirurgies urologiques. Toutefois, une analyse séparée des études comparant la MIT au TAP bloc a révélé que la MIT semblait avoir une efficacité analgésique plus prononcée.ConclusionLe TAP bloc peut jouer un rôle important dans la prise en charge de la douleur après une chirurgie abdominale en réduisant les scores de douleur et la consommation de morphine à 24 h. Il pourrait être particulièrement utile lorsque l’utilisation de techniques neuraxiales ou les opioïdes sont contre-indiqués.

Comparison of success rates, learning curves, and inter-subject performance variability of robot-assisted and manual ultrasound-guided nerve block needle guidance in simulation

BACKGROUND This study focuses on a recently developed robotic nerve block system and its impact on learning regional anaesthesia skills. We compared success rates, learning curves, performance times, and inter-subject performance variability of robot-assisted vs manual ultrasound (US)-guided nerve block needle guidance. The hypothesis of this study is that robot assistance will result in faster skill acquisition than manual needle guidance. METHODS Five co-authors with different experience with nerve blocks and the robotic system performed both manual and robot-assisted, US-guided nerve blocks on two different nerves of a nerve phantom. Ten trials were performed for each of the four procedures. Time taken to move from a shared starting position till the needle was inserted into the target nerve was defined as the performance time. A successful block was defined as the insertion of the needle into the target nerve. Average performance times were compared using analysis of variance. P<0.05 was considered significant. Data presented as mean (standard deviation). RESULTS All blocks were successful. There were significant differences in performance times between co-authors to perform the manual blocks, either superficial (P=0.001) or profound (P=0.0001); no statistical difference between co-authors was noted for the robot-assisted blocks. Linear regression indicated that the average decrease in time between consecutive trials for robot-assisted blocks of 1.8 (1.6) s was significantly (P=0.007) greater than the decrease for manual blocks of 0.3 (0.3) s. CONCLUSIONS Robot assistance of nerve blocks allows for faster learning of needle guidance over manual positioning and reduces inter-subject performance variability.

First robotic tracheal intubations in humans using the Kepler intubation system

BACKGROUND Intubation is one of the most important anaesthetic skills. We developed a robotic intubation system (Kepler intubation system, KIS) for oral tracheal intubation. METHODS In this pilot study, 12 patients were enrolled after approval of the local Ethics board and written informed consent. The KIS consists of four main components: a ThrustMaster T.Flight Hotas X joystick (Guillemot Inc., New York, NY, USA), a JACO robotic arm (Kinova Rehab, Montreal, QC, Canada), a Pentax AWS video laryngoscope (Ambu A/S, Ballerup, Denmark), and a software control system. The joystick allows simulation of the wrist or arm movements of a human operator. The success rate of intubation and intubation times were measured. RESULTS Eleven men and one woman aged 66 yr were included in this study. Intubation was successful in all but one patient using KIS at a total time of [median (inter-quartile range; range)] 93 (87, 109; 76, 153) s; in one patient, fogging of the video laryngoscope prevented intubation using KIS. CONCLUSIONS We present the first human testing of a robotic intubation system for oral tracheal intubation. The success rate was high at 91%. Future studies are needed to assess the performance and safety of such a system.

Clinical Performance and Safety of Closed-Loop Systems: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Automated systems can improve the stability of controlled variables and reduce the workload in clinical practice without increasing the risks to patients. We conducted this review and meta-analysis to assess the clinical performance of closed-loop systems compared with manual control. Our primary outcome was the accuracy of closed-loop systems in comparison with manual control to maintain a given variable in a desired target range. The occurrence of overshoot and undershoot episodes was the secondary outcome. We retrieved randomized controlled trials on accuracy and safety of closed-loop systems versus manual control. Our primary outcome was the percentage of time during which the system was able to maintain a given variable (eg, bispectral index or oxygen saturation) in a desired range or the proportion of the target measurements that was within the required range. Our secondary outcome was the percentage of time or the number of episodes that the controlled variable was above or below the target range. The standardized mean difference and 95% confidence interval (CI) were calculated for continuous outcomes, whereas the odds ratio and 95% CI were estimated for dichotomous outcomes. Thirty-six trials were included. Compared with manual control, automated systems allowed better maintenance of the controlled variable in the anesthesia drug delivery setting (95% CI, 11.7%–23.1%; percentage of time, P < 0.0001, number of studies: n = 15), in patients with diabetes mellitus (95% CI, 11.5%–30.9%; percentage of time, P = 0.001, n = 8), and in patients mechanically ventilated (95% CI, 1.5%–23.1%; percentage of time, P = 0.03, n = 8). Heterogeneity among the studies was high (>75%). We observed a significant reduction of episodes of overshooting and undershooting when closed-loop systems were used. The use of automated systems can result in better control of a given target within a selected range. There was a decrease of overshooting or undershooting of a given target with closed-loop systems.

Technical communication: First robotic ultrasound-guided nerve blocks in humans using the Magellan system.

BACKGROUND:Ultrasound-guided nerve blocks are becoming a standard of modern anesthesia. We developed a robotic system, Magellan, to perform nerve blocks using a remote control center. METHODS:Thirteen patients were enrolled in this pilot study. The Magellan system consists of 3 main components: a joystick, a robotic arm, and a software control system. The joystick allows simulation of wrist or arm movements of the proceduralist. After localization of the sciatic nerve, 35 mL of bupivacaine 0.25% was injected. The success rate of sciatic nerve blocks and block performance times (performance time = interval of time from the start of the ultrasound search for the nerve to the end of the injection of the drug; robotic time = interval of time from the identification of the nerve to the end of the injection of the drug) were determined. Data are presented as median (25th, 75th; minimal, maximal) and categorical data. RESULTS:Eight men and 5 women aged 34 years were included in this study. Nerve blocks were successful in all patients. A successful attempt was defined as the introduction of the needle into the nerve sheath; motor or sensory block was not used to determine the success rate. The nerve performance time was 189 seconds (150, 233; 90, 305), whereas the robotic time was 164 seconds (121, 210; 73, 271). CONCLUSIONS:We present the first human testing of a robotic ultrasound-guided nerve block system. The success rate was 100%. The total performance time was approximately 3 minutes to 4 minutes.

A technical description of a novel pharmacological anesthesia robot.

To control the three components of general anesthesia (hypnosis, analgesia, and neuromuscular blockade), an automated closed-loop, anesthesia-drug delivery system (McSleepy) was developed. Bispectral index was used as the control variable for hypnosis, the analgoscore for analgesia, and phonomyography for neuromuscular blockade. McSleepy can be used to control the induction, maintenance and emergence from general anesthesia. To do so, a large touch screen is used to provide a user friendly interface, permitting bidirectional communication: the user giving information about the different stages of anesthesia, and the system prompting the anesthesiologist to perform certain actions such as mask ventilation, intubation or waking-up the patient using audio clips with voice commands. Several safety features were implemented to provide a secure and reliable anesthesia. Preliminary results of 15 patients are presented in this paper. Evaluation of McSleepy was done through an assessment of its clinical performance and using Varvel’s performance indices. The system was found to be clinically useful by providing good precision in drug administration and reliable results for the duration of a general anesthesia.

Epidural catheterization in cardiac surgery: the 2012 risk assessment.

AIMS AND OBJECTIVES The risk assessment of epidural hematoma due to catheter placement in patients undergoing cardiac surgery is essential since its benefits have to be weighed against risks, such as the risk of paraplegia. We determined the risk of the catheter-related epidural hematoma in cardiac surgery based on the cases reported in the literature up to September 2012. MATERIALS AND METHODS We included all reported cases of epidural catheter placement for cardiac surgery in web and in literature from 1966 to September 2012. Risks of other medical and non-medical activities were retrieved from recent reviews or national statistical reports. RESULTS Based on our analysis the risk of catheter-related epidural hematoma is 1 in 5493 with a 95% confidence interval (CI) of 1/970-1/31114. The risk of catheter-related epidural hematoma in cardiac surgery is similar to the risk in the general surgery population at 1 in 6,628 (95% CI 1/1,170-1/37,552). CONCLUSIONS The present risk calculation does not justify not offering epidural analgesia as part of a multimodal analgesia protocol in cardiac surgery.

A Novel Mammoplasty Part-task Trainer for Simulation of Breast Augmentation: Description and Evaluation

Introduction Since the introduction of competency-based education and the restriction of residents’ working hours, simulator-aided training has obtained increasing attention for its role in teaching and assessing resident surgical skills. Within plastic surgery training, such simulators would be particularly useful for aesthetic surgery procedures such as augmentation mammoplasty where residents have fewer opportunities for hands-on experience. The aims of this study were to develop a part-task trainer that allows plastic surgery trainees to acquire skills necessary for augmentation mammoplasty and to assess its potential value as a training tool. Methods The mammoplasty part-task trainer (MPT) was designed to have a reusable and rigid thorax base and “soft” disposable layers to mimic the skin and subcutaneous tissues. A mock unilateral subglandular breast augmentation was performed by 4 board-certified plastic surgeons using standard instruments and scored using a 0 to 5 Likert scale where a score of 5 was considered the most satisfactory. Results Four board-certified plastic surgeons participated in the survey. On a scale of 0 to 5, the MPT’s “value” as a training tool, “relevance to practice,” and “physical attributes” scored highest, with mean values of 4.5, 4.3, and 4.1, respectively. “Realism of experience,” “ability to perform tasks,” and “realism of material” scored 3.9, 3.8, and 3.7, respectively. The observed average of the “global assessment” of the MPT was 4.3. The cost of fabrication of the MPT was estimated at approximately Can

The Evolution of Surgical Simulation: The Current State and Future Avenues for Plastic Surgery Education

113. Conclusions This study describes a preliminary novel mammoplasty task trainer that was highly valued by experts as a potential training tool.