G. Iohom

Perioperative plasma concentrations of stable nitric oxide products are predictive of cognitive dysfunction after laparoscopic cholecystectomy.

In this study our objectives were to determine the incidence of postoperative cognitive dysfunction (POCD) after laparoscopic cholecystectomy under sevoflurane anesthesia in patients aged >40 and <85 yr and to examine the associations between plasma concentrations of i) S-100&bgr; protein and ii) stable nitric oxide (NO) products and POCD in this clinical setting. Neuropsychological tests were performed on 42 ASA physical status I–II patients the day before, and 4 days and 6 wk after surgery. Patient spouses (n = 13) were studied as controls. Cognitive dysfunction was defined as deficit in one or more cognitive domain(s). Serial measurements of serum concentrations of S-100&bgr; protein and plasma concentrations of stable NO products (nitrate/nitrite, NOx) were performed perioperatively. Four days after surgery, new cognitive deficit was present in 16 (40%) patients and in 1 (7%) control subject (P = 0.01). Six weeks postoperatively, new cognitive deficit was present in 21 (53%) patients and 3 (23%) control subjects (P = 0.03). Compared with the “no deficit” group, patients who demonstrated a new cognitive deficit 4 days postoperatively had larger plasma NOx at each perioperative time point (P < 0.05 for each time point). Serum S-100&bgr; protein concentrations were similar in the 2 groups. In conclusion, preoperative (and postoperative) plasma concentrations of stable NO products (but not S-100&bgr;) are associated with early POCD. The former represents a potential biochemical predictor of POCD.

A clinical assessment tool for ultrasound-guided axillary brachial plexus block

Competency in anesthesia traditionally has been determined subjectively in practice. Optimal training in procedural skills requires valid and reliable forms of assessment. The objective was to examine a procedure‐specific clinical assessment tool for ultrasound‐guided axillary brachial plexus block for inter‐rater reliability and construct validity in a clinical setting.

Postoperative changes in the full-field electroretinogram following sevoflurane anaesthesia

Background and objective: We tested the hypothesis that disturbances of the visual pathway persist following general anaesthesia, even after normal clinical discharge criteria have been met. Methods: We performed full-field flash electroretinography in the right eye of 10 unpremedicated ASA I patients who underwent N2O/sevoflurane anaesthesia. Electroretinograms were recorded preoperatively, immediately after discharge from the recovery room and 2 h after discontinuation of sevoflurane. The time at which postanaesthesia discharge score first exceeded 9 was also noted. Data were analysed using paired, one-tailed Students t-test. Results: Latency of the b-wave on the photopic electroretinogram was greater at each postoperative time point (30.5 ± 0.9 and 30 ± 1.3 ms), compared to preoperative values (29.2 ± 0.8 ms, P < 0.001 and P = 0.04, respectively). The A-B amplitude of the b-wave was less postoperatively (220.3 ± 52.7 and 210.3 ± 42.7 μV) compared to values before operation (248.1 ± 57.6 μV, P = 0.03 and P = 0.01, respectively). Oscillatory potential latencies were greater at each postoperative time point (21.4 ± 0.5 and 20.8 ± 0.6 ms) compared to before operation (20.4 ± 0.4 ms, P < 0.001 and P = 0.03, respectively). Oscillatory potential amplitudes were less at the first postoperative time point (17.5 ± 6.1 μV), compared to preoperative values (22 ± 6.4 μV, P = 0.04). Conclusions: Postoperative electroretinogram abnormalities are consistently present in patients who have undergone N2O/sevoflurane anaesthesia. These abnormalities persist beyond the time at which standard clinical discharge criteria have been met.

Simulation of ultrasound-guided regional anesthesia: are we there yet?

was empirically developed and then promulgated as a standard practice. Computed tomographyYguided method is not the safest and cost-effective choice. Some of the reported disastrous complications of the cervical transforaminal steroid injections happened when CT guidance was used. Furthermore, fluoroscopy is most commonly implemented in the United States, and consequently, imaging correlation with this modality was deemed necessary. Our study did not aim to convince interventional pain specialists regarding the superiority of one technique over another. Each imaging modality has unique properties, as well as advantages and disadvantages. We believe, and here we have no disagreement with Gruber et al, that ultrasound guidance offers comparable accuracy with x-rayYbased methods, sparing practitioners and patients from harmful radiation.

Comparison of the effects of two intrathecal anaesthetic techniques for transurethral prostatectomy on haemodynamic and pulmonary function

Background and objective: Transurethral prostatectomy is routinely performed under spinal anaesthesia. This technique can cause hypotension, which is particularly undesirable in the elderly. The objective was to compare spinal anaesthesia for transurethral prostatectomy using hyperbaric bupivacaine 15 mg (control group) and hyperbaric bupivacaine 10 mg (limiting spread by maintaining the upright position for 15 min) and fentanyl 25 μg (fentanyl group) in terms of haemodynamic and pulmonary function. Methods: Thirty ASA I-III patients were randomly selected and underwent spinal anaesthesia with either hyperbaric bupivacaine 15 mg (immediately positioned supine) or hyperbaric bupivacaine 10 mg (upright for 15 min) and fentanyl 25 μg. Results: The greatest changes in mean arterial pressure (P = 0.9), ephedrine requirements (P = 0.8) and mean maximum change in forced vital capacity (P = 0.5) were similar in both groups. Conclusions: The addition of fentanyl 25 μg to bupivacaine 10 mg and limiting the spread of the block does not improve either haemodynamic or pulmonary function compared with bupivacaine 15 mg in patients undergoing transurethral prostatectomy.

Abnormalities of contrast sensitivity and electroretinogram following sevoflurane anaesthesia.

Background and objective: We tested the hypothesis that disturbances of the visual pathway following sevoflurane general anaesthesia (a) exist and persist even after clinical discharge criteria have been met and (b) are associated with decreased contrast sensitivity. Methods: We performed pattern and full-field flash electroretinograms (ERG) in 10 unpremedicated ASA I patients who underwent nitrous oxide/sevoflurane anaesthesia. ERG and contrast sensitivity were recorded preoperatively, immediately after discharge from the recovery room and 2h after discontinuation of sevoflurane. The time at which the Post Anaesthesia Discharge Score first exceeded 9 was also noted. Data were analysed using paired, one-tailed t-tests and Pearsons correlation coefficient. Results: On the full-field photopic ERG, b-wave latency was greater at each postoperative time point (31.6 ± 1.1 and 30.8 ± 1.1 ms) compared to preoperatively (30.1 ± 1.1 ms, P < 0.001 and P = 0.03, respectively). Oscillatory potential latencies were greater on discharge from the recovery room compared with preanaesthetic values (23.1 ± 3.1 vs. 22.4 ± 3.3 ms, P = 0.01) and returned to baseline by 2 h after emergence from anaesthesia. Also at 2 h after emergence from anaesthesia: (a) P50 latency on the pattern ERG was greater than at baseline (81.5 ± 17.9 vs. 51.15 ± 22.6 ms, P = 0.004); (b) N95 amplitude was less compared to preanaesthetic values (2.6 ± 0.5 vs. 3.3 ± 0.4 μV, P = 0.003) and (c) contrast sensitivity was less compared to baseline values (349 ± 153 vs. 404 ± 140, P = 0.048). A positive correlation was demonstrated between contrast sensitivity and both N95 amplitude and b-wave latency (r = 0.99 and r = −0.55 at significance levels of P < 0.005 and P < 0.05, respectively). Conclusions: Postoperative ERG abnormalities and associated decreases in contrast sensitivity are consistently present in patients who have undergone nitrous oxide/sevoflurane anaesthesia. These abnormalities persist beyond the time at which standard clinical discharge criteria have been met.

A comparison of the efficacy of local anaesthetic wound infiltration versus intrathecal morphine for postoperative analgesia following total knee arthroplasty: 8AP6-3

Background: Ef fective analgesia following total knee arthroplasty may be provided using intrathecal opioids, epidural analgesia or continuous peripheral nerve blockade (1). Local anaesthetic infiltration has proved superior to epidural analgesia and femoral nerve blockade (2, 3). To date, no study comparing this technique with intrathecal morphine has been published. Objective: To evaluate the analgesic ef ficacy of intraand peri-articular plus wound infiltration with levobupivacaine in comparison with intrathecal morphine following total knee arthroplasty. The primary outcome measure was analgesia in the first 48 postoperative hours as assessed by visual analogue scale (VAS) scores for pain. A secondary outcome measure was morphine consumption. Methodology: In this prospective, randomized controlled trial patients were randomized to one of two groups. Patients in the standard group (S) received spinal anaesthesia with intrathecal bupivacaine and morphine 0.3 mg. Patients in the infiltration group (I) received spinal anaesthesia with intrathecal bupivacaine without morphine, and infiltration with levobupivacaine 0.5% 2mg/kg body weight plus 0.5mg epinephrine made up to a volume of 100ml with normal saline. An intra-articular catheter was sited prior to wound closure and a bolus of 15 ml levobupivacaine 0.5% was given on the first postoperative day. Patients‘ VAS for pain was assessed at 2, 6, 12, 24 and 48 hours both at rest and on movement (passive flexion to 30°). Total analgesic consumption in the form of morphine PCA use was recorded. Results: Out of the planned 36 patients 20 have been recruited to date (10 to group S, 10 to group I). Mean VAS scores for pain show a trend towards being lower in the infiltration group Vs the standard group at both 24 and 48 hours (Table 1).

Effect of feedback on novices learning in-plane technique for ultrasound guided interventional procedures: 15AP2-5

for paired digits also! Conclusion(s): Applying Benford’s on the assessment of the presented digits (numbers) in the retrieved articles known as fabricated and therefore withdrawn by the editors, resulted in a astonishing evidence for falsification when the financial auditing method by using Benford’s law was applied. Further studies are needed to evaluate the power of this method to detect fabricated data in the field of medicine. To our knowledge, this is the first time that results of this method for anaesthesia research papers are reported.Fraud detection using statistical methods is a post hoc strategy, being applied af ter fraud prevention has failed.