Faculty Bibliography

Transient neurologic symptoms (TNS) led to the abandonment of intrathecal lidocaine. We reviewed the published literature for information about the duration of action and side effects of intrathecal prilocaine, which has been recently reintroduced in Europe. Medline and EMBASE databases were searched for the time period from 1966 to 2014. Fourteen prospective and one retrospective study were retrieved. The duration of the surgical block can be adjusted using doses between 40 and 80mg. Hyperbaric prilocaine in doses as low as 10mg can be used for perianal procedures. Four cases of TNS in 486 patients were reported in prospective studies, and none in 5000 cases in a retrospective data set. Spinal prilocaine appears to be safe and reliable for day case anesthesia. However, as chloroprocaine has a shorter duration and a lower risk of TNS and urinary retention, the indications for prilocaine remain to be defined.

OBJECTIVE: Our aim was to establish a plasma concentration curve for ropivacaine following femoral nerve blockade and to ascertain whether the resulting plasma concentrations differ significantly depending on whether neurostimulation (NS) or ultrasound (US) guidance was used. METHODS: Sixteen male and female subjects aged 18 to 80 who were scheduled to undergo unilateral total knee replacement or anterior cruciate ligament reconstruction under general or spinal anaesthesia, and for whom a femoral nerve block was indicated for postoperative analgesia, were enrolled in this prospective, randomised study. Patients were randomised to undergo either US or NS-guidance femoral nerve blocks. All blocks were performed with 20mL of 5mg/mL ropivacaine. Blood samples were drawn before the nerve block and 20, 30, 40, 50, 60, 70, and 80minutes after the block. Plasma levels of ropivacaine were analysed by high performance liquid chromatography (HPLC). RESULTS: All blocks were successful and no patient showed signs or symptoms of local anaesthetic toxicity. The plasma concentration of ropivacaine peaked at 30minutes in both arms. There was no significant difference in peak levels between US and NS-guidance (0.325+/-0.186 versus 0.356+/-0.106mug/mL). Cmax and tmax were very similar between groups (0.364+/-0.177 versus 0.344+/-0.127mug/mL, 33.75+/-15.06 versus 31.25+/-13.56min for US and NS, respectively). CONCLUSION: Plasma concentrations of ropivacaine peak around 30minutes after a femoral nerve block regardless of the technique used. No significant difference was found between US- and NS-guidance.

This is the protocol for a review and there is no abstract. The objectives are as follows: The objective of this review is to compare the effects of regional versus general anaesthesia on cognitive function after procedures other than cardiac surgery or neurosurgery in adult and in paediatric patients.

BACKGROUND: Regional analgesia is more effective than conventional analgesia for controlling pain and may facilitate rehabilitation after large joint replacement in the short term. It remains unclear if regional anaesthesia improves functional outcomes after joint replacement beyond three months after surgery. OBJECTIVES: To assess the effects of regional anaesthesia and analgesia on long-term functional outcomes 3, 6 and 12 months after elective major joint (knee, shoulder and hip) replacement surgery. SEARCH METHODS: We performed an electronic search of several databases (CENTRAL, MEDLINE, EMBASE, CINAHL), and handsearched reference lists and conference abstracts. We updated our search in June 2015. SELECTION CRITERIA: We included randomized controlled trials (RCTs) comparing regional analgesia versus conventional analgesia in patients undergoing total shoulder, hip or knee replacement. We included studies that reported a functional outcome with a follow-up of at least three months after surgery. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. We contacted study authors for additional information. MAIN RESULTS: We included six studies with 350 participants followed for at least three months. All of these studies enrolled participants undergoing total knee replacement. Studies were at least partially blinded. Three studies had a high risk of performance bias and one a high risk of attrition bias, but the risk of bias was otherwise unclear or low.Only one study assessed joint function using a global score. Due to heterogeneity in outcome and reporting, we could only pool three out of six RCTs, with range of motion assessed at three months after surgery used as a surrogate for joint function. All studies had a high risk of detection bias. Using the random-effects model, there was no statistically significant difference between the experimental and control groups (mean difference 3.99 degrees, 95% confidence interval (CI) - 2.23 to 10.21; P value = 0.21, 3 studies, 140 participants, very low quality evidence).We did not perform further analyses because immediate adverse effects were not part of the explicit outcomes of any of these typically small studies, and long-term adverse events after regional anaesthesia are rare.None of the included studies elicited or reported long-term adverse effects like persistent nerve damage. AUTHORS' CONCLUSIONS: More high-quality studies are needed to establish the effects of regional analgesia on function after major joint replacement, as well as on the risk of adverse events (falls).