Intraneural Ultrasound-guided Sciatic Nerve Block: Minimum Effective Volume and Electrophysiologic Effects.

WHAT WE ALREADY KNOW ABOUT THIS TOPIC: WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: Both extra- and intraneural sciatic injection resulted in significant axonal nerve damage. This study aimed to establish the minimum effective volume of intraneural ropivacaine 1% for complete sensory-motor sciatic nerve block in 90% of patients, and related electrophysiologic variations. METHODS: Forty-seven consecutive American Society of Anesthesiologists physical status I-II patients received an ultrasound-guided popliteal intraneural nerve block following the up-and-down biased coin design. The starting volume was 15 ml. Baseline, 5-week, and 6-month electrophysiologic tests were performed. Amplitude, latency, and velocity were evaluated. A follow-up telephone call at 6 months was also performed. RESULTS: The minimum effective volume of ropivacaine 1% in 90% of patients for complete sensory-motor sciatic nerve block resulted in 6.6 ml (95% CI, 6.4 to 6.7) with an onset time of 19 ± 12 min. Success rate was 98%. Baseline amplitude of action potential (mV) at ankle, fibula, malleolus, and popliteus were 8.4 ± 2.3, 7.1 ± 2.0, 15.4 ± 6.5, and 11.7 ± 5.1 respectively. They were significantly reduced at the fifth week (4.3 ± 2.1, 3.5 ± 1.8, 6.9 ± 3.7, and 5.2 ± 3.0) and at the sixth month (5.9 ± 2.3, 5.1 ± 2.1, 10.3 ± 4.0, and 7.5 ± 2.7) (P < 0.001 in all cases). Latency and velocity did not change from the baseline. No patient reported neurologic symptoms at 6-month follow-up. CONCLUSIONS: The intraneural ultrasound-guided popliteal local anesthetic injection significantly reduces the local anesthetic dose to achieve an effective sensory-motor block, decreasing the risk of systemic toxicity. Persistent electrophysiologic changes suggest possible axonal damage that will require further investigation.

Transversus Abdominis Plane Block for Postoperative Analgesia in Patients Undergoing Total Laparoscopic Hysterectomy: A Randomized, Controlled, Observer-Blinded Trial.

BACKGROUND: In this randomized, controlled, observer-blinded study, we evaluated analgesia provided by transversus abdominis plane (TAP) block after elective total laparoscopic hysterectomy in terms of reduced postoperative morphine consumption as the primary end point. METHODS: Fifty-two patients were randomly divided into 2 groups: patients in group T (TAP, n = 26) received an ultrasound-guided bilateral TAP block with 40 mL of 0.375% levobupivacaine and morphine patient-controlled analgesia, whereas patients in group C (control, n = 26) received morphine patient-controlled analgesia. Secondary outcomes included pain measurements (Numeric Rating Scale from 0 to 10) during the first 24 hours postoperatively, times to postanesthesia care unit discharge, times to surgical ward discharge, incidence of postoperative nausea and vomiting, functional capacity measurements in terms of 2-minute walking test, and first oral solid intake. RESULTS: Demographic and anthropometric variables were similar in the 2 groups. The total dose of morphine consumed by patients during postanesthesia care unit stay was 6 (0-8) mg in group T vs 8 (5.5-8.5) mg in group C (P = 0.154). Postoperative morphine consumption during the first 24 hours was 10.55 ± 10.24 mg in group C vs 10.73 ± 13.45 mg in group T (P = 0.950). The 95% confidence interval of the difference between means of 24-hour morphine consumption was -7.45 to +7.09. The 2 groups were comparable. There were no significant differences in secondary outcome variables between groups. CONCLUSIONS: TAP block did not reduce morphine consumption during the first postoperative 24 hours after elective total laparoscopic hysterectomy.

Groin Pain Syndrome Italian Consensus Conference update 2023.

Groin pain syndrome (GPS) is a controversial topic in Sports Medicine. The GPS Italian Consensus Conference on terminology, clinical evaluation and imaging assessment of groin pain in athletes was organized by the Italian Society of Arthroscopy in Milan, on 5 February 2016. In this Consensus Conference (CC) GPS etiology was divided into 11 different categories for a total of 63 pathologies. The GPS Italian Consensus Conference update 2023 is an update of the 2016 CC. The CC was based on a sequential, two-round online Delphi survey, followed by a final CC in the presence of all panelists. The panel was composed of 55 experts from different scientific and clinical backgrounds. Each expert discussed 6 different documents, one of which regarded the clinical and imaging definition of sports hernias, and the other 5 dealt with 5 new clinical situations thought to result in GPS. The panelists came to an agreement on the definition of a sports hernia. Furthermore, an agreement was reached, recognizing 4 of the 5 possible proposed pathologies as causes to GPS. On the contrary, the sixth pathology discussed did not find consensus given the insufficient evidence in the available scientific literature. The final document includes a new clinical and imaging definition of sports hernia. Furthermore, the etiology of GPS was updated compared to the previous CC of 2016. The new taxonomic classification includes 12 categories (versus 11 in the previous CC) and 67 pathologies (versus 63 in the previous CC).

The efficacy of a resistive heating under-patient blanket versus a forced-air warming system: a randomized controlled trial.

BACKGROUND: We compared temperature changes in patients undergoing hip replacement during warming with a resistive heating blanket or air-forced system. METHODS: Fifty-six patients were enrolled. Patients were randomly allocated to the "forced-air group" (forced-air system) or to the "heating-blanket group" (resistive heating under-patient blanket). RESULTS: Baseline tympanic temperatures were 36.0 +/- 0.6 degrees C in the forced-air group and 36.1 +/- 0.4 degrees C in the heating-blanket group (P > 0.05). At the end of surgery tympanic temperatures were 35.3 +/- 0.5 degrees C in the forced-air group and 35.1 +/- 0.6 degrees C in the heating-pad group (P > 0.05). CONCLUSIONS: We demonstrated that, using either a resistive heating-blanket or forced-air warming systems, patients ended surgery in mild hypothermia after elective total hip replacement, but without significant differences between these two warming devices.

The effects of ultrasound guidance and neurostimulation on the minimum effective anesthetic volume of mepivacaine 1.5% required to block the sciatic nerve using the subgluteal approach.

BACKGROUND: We tested the hypothesis that ultrasound (US) guidance may reduce the minimum effective anesthetic volume (MEAV(50)) of 1.5% mepivacaine required to block the sciatic nerve with a subgluteal approach compared with neurostimulation (NS). METHODS: After premedication and single-injection femoral nerve block, 60 patients undergoing knee arthroscopy were randomly allocated to receive a sciatic nerve block with either NS (n = 30) or US (n = 30). In the US group, the sciatic nerve was localized between the ischial tuberosity and the greater trochanter. In the NS group, the appropriate muscular response (foot plantar flexion or inversion) was elicited (1.5 mA, 2 Hz, 0.1 ms) and maintained to

Stimulating versus non-stimulating catheter for lumbar plexus continuous infusion after total hip replacement.

BACKGROUND: This study was aimed to investigate whether stimulating catheters for continuous lumbar plexus block reduce local anesthetic consumption after hip arthroplasty if compared with traditional non-stimulating catheters. METHODS: Seventy-two ASA I-III, 18-82-year-old, undergoing primary hip replacement (THA) for osteoarthritis with spinal anesthesia were randomized into two groups: Stim group (stimulating catheter, N.=36) and Nonstim group (non-stimulating catheter, N.=36). After surgery, 15 mL of mepivacaine 1% were administered in both groups through the catheter. An electronic pump was connected to deliver ropivacaine 0.2% (3 mL/h, bolus 3 mL, lock out 15 min) for the first 72 h. Patients were given ketorolac 30 mg IV every 8 h, acetaminophen 1g IV every 8 h and oxycodone 10 mg per os for rescue analgesia. Primary outcome was postoperative local anesthetic consumption. Numerical Rating Scale (NRS), complications, both quadriceps and obturator strength measurements, and opioid requirement were also registered. Mixed effect models (random intercept) were built for repeated measures over time. A difference between groups was considered statistically significant if P<0.05. RESULTS: Local anesthetic consumption and NRS were comparable between groups. Patients in the Nonstim group required significant more rescue opioid analgesia compared with the Stim group during the first 36 h (P=0.002). Quadriceps and adductor muscle strength was equally preserved in the two groups. CONCLUSIONS: The study showed comparable local anesthetic consumption, pain scores and muscle strength preservation between the two groups. The stimulating catheter allowed a significant, although underpowered, reduction in opioid consumption.

Spinal anesthesia with lidocaine or preservative-free 2-chlorprocaine for outpatient knee arthroscopy: a prospective, randomized, double-blind comparison.

BACKGROUND: In this prospective, randomized, double-blind study we tested the hypothesis that 50 mg of 1% preservative-free 2-chloroprocaine would provide a faster resolution of spinal block than the same dose of 1% plain lidocaine. METHODS: After IV midazolam premedication (0.03 mg/kg), 30 ASA physical status I-II outpatients undergoing knee arthroscopy were randomly allocated to receive 50 mg of either 1% plain lidocaine (n = 15) or 1% preservative-free plain chloroprocaine (n = 15). A blinded observer recorded the evolution of sensory (loss of pinprick sensation) and motor (modified Bromage scale) block until complete regression, as well as times to unassisted ambulation and voiding. A telephone call follow-up was performed 24 h and 7 days after surgery. RESULTS: Two chloroprocaine patients (13%) and one lidocaine patient (7%) required fentanyl supplementation (100 microg IV) (P = 0.99) intraoperatively, but no patient required general anesthesia to complete surgery. Median (range) times for recovery of sensory and motor function, and unassisted ambulation were faster with 2-chloroprocaine [95 (68-170) min; 60 (45-120) min; and 103 (70-191) min] than lidocaine [120 (80-175) min; 100 (60-140) min; and 152 (100-185) min] (P = 0.019, P = 0.0005, and P = 0.003, respectively). No differences in first voiding were reported between chloroprocaine [180 (100-354) min] and lidocaine patients [190 (148-340) min] (P = 0.191). Transient neurological symptoms were reported in five lidocaine patients (33%) but no chloroprocaine patients (0%) (P = 0.042). CONCLUSION: Intrathecal injection of 50 mg of preservative-free 2-chloroprocaine 1% resulted in quicker recovery of sensory/motor function, and unassisted ambulation, and fewer incidences of transient neurologic symptoms than the same dose of 1% lidocaine.

Intrathecal 2-chloroprocaine for lower limb outpatient surgery: a prospective, randomized, double-blind, clinical evaluation.

We evaluated the dose-response relationship of 2-chloroprocaine for lower limb outpatient procedure in 45 ASA physical status I-II outpatients undergoing elective lower limb surgery under spinal anesthesia, with 30 mg (group Chlor-30, n = 15), 40 mg (group Chlor-40, n = 15), or 50 mg (group Chlor-50, n = 15) of 1% preservative free 2-chloroprocaine. Onset time was similar in the three groups. General anesthesia was never required to complete surgery. Intraoperative analgesic supplementation as a result of insufficient duration of spinal block was required in 5 patients of group Chlor-30 (35%) and 2 patients of group Chlor-40 (13%) (P = 0.014), with a median (range) time for supplementation request of 40 (30-60) min. Spinal block resolution and recovery of ambulation were faster in group Chlor-30 (60 [41-98] min and 85 [45-123] min) than in groups Chlor-40 (85 [46-141] min and 180 [72-281] min) and Chlor-50 (97 [60-169] min and 185 [90-355] min) (P = 0.001 and P = 0.003, respectively), with no differences in home discharge time (182 [120-267] min in group Chlor-30, 198 [123-271] min in group Chlor-40, and 203 [102-394] min in group Chlor-50; P = 0.155). No transient neurologic symptoms were reported at 24-h and 7-day follow-up. We conclude that although 40 and 50 mg of 2-chloroprocaine provide adequate spinal anesthesia for outpatient procedures lasting 45-60 min, 30 mg produces a spinal block of insufficient duration.

Does clonidine 50 microg improve cervical plexus block obtained with ropivacaine 150 mg for carotid endarterectomy? A randomized, double-blinded study.

STUDY OBJECTIVE: To evaluate the effects of adding 50 microg clonidine to 150 mg ropivacaine for superficial cervical plexus block in patients undergoing elective carotid endarterectomy (TEA). DESIGN: Randomized, double-blind study. SETTING: Departments of Anesthesia and Vascular Surgery of a university hospital. PATIENTS: 40 ASA physical status II and III patients undergoing elective TEA during superficial cervical plexus block. INTERVENTIONS: Superficial cervical plexus block was placed using 20 mL of 0.75% ropivacaine alone (Ropi group, n = 20) or with the addition of 50 microg clonidine (Ropi-Clonidine group, n = 20). If required, analgesic supplementation was given with local infiltration with 1% lidocaine and intravenous fentanyl (50-microg boluses). Nerve block profile, need for intraoperative analgesic supplementation, and time to first analgesic request were recorded. MEASUREMENTS AND MAIN RESULTS: Median (range) onset time was 10 minutes (5-25 min) in the Ropi group and 5 minutes (5-20 min) in the Ropi-Clonidine group (P < 0.05). Intraoperative consumption of both 1% lidocaine and fentanyl was higher in patients of the Ropi group (15 mL [0-25 mL] and 250 microg [50-300 microg]) than in patients of the Ropi-Clonidine group (8 mL [0-20 mL] and 0 microg [0-150 microg]; P < 0.05 and P < 0.05, respectively). First postoperative analgesic request occurred after 17 hours (10-24 hrs) in the Ropi group and 20 hours (10-24 hrs) in the Ropi-Clonidine group (P > 0.05). CONCLUSIONS: Adding 50 microg clonidine to 150 mg ropivacaine for superficial cervical plexus block shortened the onset time and improved the quality of surgical anesthesia in patients undergoing elective TEA.

Italian Registry of Complications associated with Regional Anesthesia (RICALOR). An incidence analysis from a prospective clinical survey.

BACKGROUND: Regional anesthesia (RA) is associated with many advantages, but side effects also occur. Several registries were developed to investigate such complications in many countries, which produced conflicting results. In consideration of the ongoing evolution and improvements in RA, and its widespread diffusion in Italy in the last decade (with increasing experience by anesthesiologists), a reappraisal of the incidence and the characteristics of major complications are useful to improve patient's safety. METHODS: A web-based prospective registry was developed in Italy with: 1) quarterly report of total anesthetic acts and RA procedures performed; and 2) voluntary registration of complications on dedicated forms. We evaluated incidence of complications, describing their characteristics and outcomes. RESULTS: Participants (N.=17 hospitals) registered 117,182 procedures, including 63,692 with RA (54.3%, both as primary anesthetic technique and for postoperative analgesia). A total of 34,147 neuraxial blocks (4954 epidurals/CSE, 29,193 subarachnoid blocks) and 29,545 peripheral (single shot and continuous) blocks were registered. Total incidence of complication was 4.6/10.000; incidence was 4.1/10,000 for central blocks and 5.1/10,000 for peripheral blocks, long-term neurologic deficit (at 6 months) was observed after an epidural abscess, while other complications did not lead to any long-term adverse outcomes. No hemorrhagic events or other infections have occurred. Incidence of major complications was 0.07/1000, while minor complications presented in 0.38/1000 cases. CONCLUSIONS: We confirmed RA as generally safe, but monitoring and diagnosis, together with further research efforts, are needed to improve patients' care and clarify potential risk factors.

The use of vitamin B1 as a perineural adjuvant to middle interscalene block for postoperative analgesia after shoulder surgery.

BACKGROUND: Perineural administration of thiamine, via axonal flow, could strenghthen synthesis of ACh in the dorsal horn inhibitory interneurons, thus potentiating analgesia. The purpose of the present retrospective analysis is therefore to investigate whether adding perineurally 2 mg/Kg of thiamine to 0.75% levobupivacaine in patients undergoing middle interscalene block may prolong the duration of analgesia. METHOD: The hospital records of all ASA status 1-2 patients, undergoing a single-shot interscalene block for arthroscopic rotator cuff repair from January 2011 to May 2012 were retrospectively reviewed. All blocks were performed with 0.75% levobupivacaine or a solution of thiamine hydrochloride and 0.75% levobupivacaine. The local anesthetic solution, postoperative visual analogue score for pain at rest and rescue medication were registered. We calculated the time interval elapsing between block anesthetic mixture injection and the patient's first analgesic requirement, ie time to end of analgesia. Eventual postoperative side effects were also reported. RESULTS: 59 patients received 0.4 ml/Kg of 0.75% levobupivacaine (Group L) and 51 patients received a mixture of 2 mg/Kg of thiamine hydrocloride (maximum dose 200 mg) with 0.4 ml/Kg of 0.75% levobupivacaine (Group B1). Tea was 11.4 ± 3.0 hours in Group L versus 17.6 ± 3.0 hours in Group B1 (p < 0.001). The scores for pain in the two Groups at the time of the first analgesic rescue were comparable. CONCLUSION: The present retrospective analysis suggests that thiamine helps to prolong postoperative analgesia when added to the local anesthetic solution. Further prospective studies are necessary to confirm these preliminary results.Word count: 250.

Unilateral paravertebral block compared with subarachnoid anesthesia for the management of postoperative pain syndrome after inguinal herniorrhaphy: a randomized controlled clinical trial.

Inguinal herniorrhaphy is a common surgical procedure. The aim of this investigation was to determine whether unilateral paravertebral block could provide better control of postoperative pain syndrome compared with unilateral subarachnoid block (SAB). A randomized controlled study was conducted using 50 patients with unilateral inguinal hernias. The patients were randomized to receive either paravertebral block (S group) or SAB (C group). Paravertebral block was performed by injecting a total of 20 mL of 0.5% levobupivacaine from T9 to T12 under ultrasound guidance, whereas SAB was performed by injecting 13 mg of 0.5% levobupivacaine at the L3 to L4 level. Data regarding anesthesia, hemodynamic changes, side effects, time spent in the postanesthesia care unit, the Karnofsky Performance Status, acute pain and neuropathic disturbances were recorded. Paravertebral block provided good anesthesia of the inguinal region without patient or surgeon discomfort, with better hemodynamic stability and safety and with a reduced time to discharge from the postanesthesia care unit compared with SAB. During the postsurgical and posthospital discharge follow-ups, rest and incident pain and neuropathic positive phenomena were better controlled in the S group than in the C group. The consumption of painkillers was higher in the C group than in the S group throughout the follow-up period. Paravertebral block can be considered a viable alternative to common anesthetic procedures performed for inguinal hernia repair surgery. Paravertebral block provided good management of acute postoperative pain and limited neuropathic postoperative disturbances.

Spinal ropivacaine or bupivacaine for cesarean delivery: a prospective, randomized, double-blind comparison.

BACKGROUND AND OBJECTIVES: The aim of this prospective, randomized, double-blinded study was to compare clinical efficacy and safety of ropivacaine and bupivacaine given intrathecally in combination with morphine for cesarean delivery. METHODS: With ethical committee approval and a written informed consent, 60 women scheduled for elective cesarean delivery under spinal anesthesia were randomly allocated to receive spinal anesthesia with either 20 mg ropivacaine plus 0.1 mg morphine (n = 30) or 15 mg bupivacaine plus 0.1 mg morphine (n = 30). Profile of spinal block (onset and recovery times), cardiovascular effects, and quality of postoperative analgesia (patient-controlled morphine) were recorded by a blinded observer. RESULTS: The onset time of motor block was shorter after bupivacaine (8 +/- 2 min) than after ropivacaine (12 +/- 5 minutes) (P <.05), whereas duration of both sensory and motor blocks was longer after bupivacaine (139 +/- 37 minutes and 254 +/- 76 minutes) than after ropivacaine (112 +/- 27 minutes and 211 +/- 48 minutes) (P <.01 and P <.05, respectively). No differences in intraoperative quality of anesthesia and clinical hypotension requiring ephedrine administration were observed between the two groups. Postoperative analgesia was similarly effective in both groups; however median consumption of patient-controlled morphine during the first 24 hours after surgery was higher in patients of group Ropivacaine (5 mg; range, 0 to 18 mg) than in patients of group Bupivacaine (2 mg; range, 0 to 7 mg) (P <.01). CONCLUSION: Spinal anesthesia produced with 20 mg ropivacaine plus 0.1 mg morphine is as effective and safe as that provided by 15 mg bupivacaine plus 0.1 mg morphine, with an earlier recovery of sensory and motor functions after surgery.

Effects of baricity of 0.5% or 0.75% levobupivacaine on the onset time of spinal anesthesia: a randomized trial.

PURPOSE: Levobupivacaine has been extensively evaluated for spinal anesthesia. Its pharmacologic properties are similar to those of bupivacaine, but differences in density between two commercially-available preparations of plain levobupivacaine might lead to different block profiles. We examined the characteristics of spinal anesthesia using the same dose of 0.5% and 0.75% plain levobupivacaine. METHODS: In this randomized, controlled, double-blind clinical trial, 60 ASA I-III patients, scheduled for hip fracture surgery, were randomly allocated to receive spinal anesthesia with 15 mg of either 0.5% (group Levo-0.5), or 0.75% (group Levo-0.75) plain levobupivacaine. Onset time (primary outcome), sensory block height level by pinprick, motor block using a modified Bromage scale, and hemodynamic variables were recorded. RESULTS: In group Levo-0.5 (n = 29), surgical anesthesia was obtained within 15 (10-20) min, compared to 12 (7-21) min in group Levo-0.75 (n = 31) (p = 0.409). The highest sensory block level was T11 (T6-T12) in group Levo-0.5, and T10 (T8 - T12) in group Levo-0.75 (p = 0.759). Mean duration of anesthesia was 285 (224-303) min in group Levo-0.5, and 318 (243-375) min in group Levo-0.75 (p = 0.117). The groups were similar in regards to the number of failed blocks requiring general anesthesia, and the number of patients requiring vasopressors. CONCLUSIONS: In this population of elderly patients, spinal anesthesia with 15 mg of either 0.5% or 0.75% plain levobupiva-caine resulted in similar onset of pharmacological actions, and outcomes. Potential differences in baricity did not appear to be clinically relevant in this setting.

A prospective, randomized comparison between ultrasound and nerve stimulation guidance for multiple injection axillary brachial plexus block.

BACKGROUND: This prospective, randomized, blinded study tested the hypothesis that ultrasound guidance can shorten the onset time of axillary brachial plexus block as compared with nerve stimulation guidance when using a multiple injection technique. METHODS: Sixty American Society of Anesthesiology physical status I-III patients receiving axillary brachial plexus block with 20 ml ropivacaine, 0.75%, using a multiple injection technique, were randomly allocated to receive either nerve stimulation (group NS, n = 30), or ultrasound guidance (group US, n = 30) for nerve location. A blinded observer recorded the onset of sensory and motor blocks, the need for general anesthesia (failed block) or greater than 100 microg fentanyl (insufficient block) to complete surgery, procedure-related pain, success rate, and patient satisfaction. RESULTS: The median (range) number of needle passes was 4 (3-8) in group US and 8 (5-13) in group NS (P = 0.002). The onset of sensory block was shorter in group US (14 +/- 6 min) than in group NS (18 +/- 6 min) (P = 0.01), whereas no differences were observed in onset of motor block (24 +/- 8 min in group US and 25 +/- 8 min in group NS; P = 0.33) and readiness to surgery (26 +/- 8 min in group US and 28 +/- 9 min in group NS; P = 0.48). No failed block was reported in either group. Insufficient block was observed in 1 patient (3%) of group US and 2 patients (6%) of group NS (P = 0.61). Procedure-related pain was reported in 6 patients (20%) of group US and 14 patients (48%) of group NS (P = 0.028); patient acceptance was similarly good in the two groups. CONCLUSION: Multiple injection axillary block with ultrasound guidance provided similar success rates and comparable incidence of complication as compared with nerve stimulation guidance.

Monitoring cerebral oxygen saturation in elderly patients undergoing general abdominal surgery: a prospective cohort study.

BACKGROUND AND OBJECTIVES: The aim of this prospective, observational study was to evaluate changes in regional cerebral oxygen saturation (rSO2) and incidence of intraoperative cerebral desaturation in a cohort of elderly patients undergoing major abdominal surgery. METHODS: rSO2 was continuously monitored on the left and right sides of the forehead in 60 patients older than 65 yr (35 males and 25 females; ASA II-III; age: 72 +/- 5 yr; without pre-existing cerebral pathology, and baseline Mini Mental State Examination (MMSE) score >23) undergoing sevoflurane anaesthesia for major abdominal, non-vascular surgery >2 h. RESULTS: Baseline rSO2 was 63 +/- 8%; cerebral desaturation (rSO2 decrease <75% of baseline or <80% in case of baseline rSO2 <50%) occurred in 16 patients (26%). The MMSE decreased from 28 +/- 1 before surgery to 27 +/- 2 on 7th postoperative day (P = 0.05). A decline in cognitive function (decrease in MMSE score > or = 2 points one week after surgery as compared to baseline value) was observed in six patients without intraoperative cerebral desaturation (13.6%) and six patients who had intraoperative cerebral desaturation (40%) (P = 0.057) (odds ratio: 4.22; CI95%: 1.1-16). Median (range) hospital stay was 14 (5-41) days in patients with an area under the curve of rSO2 <50% (AUCrSO2<50%) >10 min%, and 10 (4-30) days in those with an AUCrSO2<50% <10 min% (P = 0.0005). CONCLUSIONS: In a population of healthy elderly patients, undergoing non-vascular abdominal surgery cerebral desaturation can occur in up to one in every four patients, and the occurrence of cerebral desaturation is associated with a higher incidence of early postoperative cognitive decline and longer hospital stay.

Spinal anesthesia with hyperbaric levobupivacaine and ropivacaine for outpatient knee arthroscopy: a prospective, randomized, double-blind study.

To compare unilateral spinal block produced with small doses of hyperbaric ropivacaine with that produced by 2 doses of hyperbaric levobupivacaine, we randomly allocated 91 ASA physical status I-II outpatients undergoing knee arthroscopy to receive unilateral spinal anesthesia with 7.5 mg of hyperbaric ropivacaine 0.5% (group Ropi-7.5, n = 31) or either 7.5 mg (group Levo-7.5, n = 30) or 5 mg (group Levo-5, n = 30) of hyperbaric levobupivacaine 0.5%. Spinal anesthesia was performed at the L3-4 interspace using a 25-gauge Whitacre spinal needle. The lateral decubitus position was maintained for 15 min after injection. Strictly unilateral sensory block was present in 73%, 50%, and 61% of cases in groups Ropi-7.5, Levo-7.5, and Levo-5, respectively, 30 min after injection (P = 0.40), and unilateral motor block was observed in 94%, 93%, and 83% in groups Ropi-7.5, Levo-7.5, and Levo-5, respectively (P = 0.31). One patient of group Ropi-7.5 required general anesthesia to complete surgery, and fentanyl supplementation was required in one patient of group Ropi-7.5 (3%) and one patient of group Levo-5 (3%) (P = 0.42). The median (range) time for spinal block resolution was shorter in group Ropi-7.5 (135 [126-154] min] than in group Levo-7.5 (162 [148-201] min) (P = 0.04); whereas home discharge was shorter in groups Ropi-7.5 (197 [177-218] min) and Levo-5 (197 [187-251] min) as compared with group Levo-7.5 (238 [219-277] min) (P = 0.02 and P = 0.04, respectively). We conclude that 7.5 mg of 0.5% hyperbaric ropivacaine and 5 mg of 0.5% hyperbaric levobupivacaine provide adequate spinal block for outpatient knee arthroscopy, with a faster home discharge as compared with 7.5 mg of 0.5% hyperbaric levobupivacaine.

Continuous monitoring of cerebral oxygen saturation in elderly patients undergoing major abdominal surgery minimizes brain exposure to potential hypoxia.

Elderly patients are more prone than younger patients to develop cerebral desaturation because of the reduced physiologic reserve that accompanies aging. To evaluate whether monitoring cerebral oxygen saturation (rSO(2)) minimizes intraoperative cerebral desaturation, we prospectively monitored rSO(2) in 122 elderly patients undergoing major abdominal surgery with general anesthesia. Patients were randomly allocated to an intervention group (the monitor was visible and rSO(2) was maintained at > or =75% of preinduction values; n = 56) or a control group (the monitor was blinded and anesthesia was managed routinely; n = 66). Cerebral desaturation (rSO(2) reduction <75% of baseline) was observed in 11 patients of the treatment group (20%) and 15 patients of the control group (23%) (P = 0.82). Mean (95% confidence intervals) values of mean rSO(2) were higher (66% [64%-68%]) and the area under the curve below 75% of baseline (AUCrSO2(2)< 75% of baseline) was lower (0.4 min% [0.1-0.8 min%]) in patients of the treatment group than in patients of the control group (61% [59%-63%] and 80 min% [2-144 min%], respectively; P = 0.002 and P = 0.017). When considering only patients developing intraoperative cerebral desaturation, a lower Mini Mental State Elimination (MMSE) score was observed at the seventh postoperative day in the control group (26 [25-30]) than in the treatment group (28 [26-30]) (P = 0.02), with a significant correlation between the AUCrSO(2) < 75% of baseline and postoperative decrease in MMSE score from preoperative values (r(2)= 0.25, P = 0.01). Patients of the control group with intraoperative cerebral desaturation also experienced a longer time to postanesthesia care unit (PACU) discharge (47 min [13-56 min]) and longer hospital stay (24 days [7-53] days) compared with patients of the treatment group (25 min [15-35 min] and 10 days [7-23 days], respectively; P = 0.01 and P = 0.007). Using rSO(2) monitoring to manage anesthesia in elderly patients undergoing major abdominal surgery reduces the potential exposure of the brain to hypoxia; this might be associated with decreased effects on cognitive function and shorter PACU and hospital stay.

Using stimulating catheters for continuous sciatic nerve block shortens onset time of surgical block and minimizes postoperative consumption of pain medication after halux valgus repair as compared with conventional nonstimulating catheters.

UNLABELLED: We prospectively tested the hypothesis that the use of a stimulating catheter improves the efficacy of continuous posterior popliteal sciatic nerve block in 100 randomized patients scheduled for elective orthopedic foot surgery. After eliciting a sciatic mediated muscular twitch at < or = 0.5 mA nerve stimulation output, the perineural catheter was advanced 2-4 cm beyond the tip of the introducer either blindly (Group C; n = 50) or stimulating via the catheter (Group S; n = 50). A bolus dose of 25 mL of 1.5% mepivacaine was followed by a postoperative patient-controlled infusion of 0.2% ropivacaine (basal infusion: 3 mL/h; incremental dose: 5 mL; lockout time: 30 min). Propacetamol 2 g IV was administered every 8 h, and opioid rescue analgesia was available if required. Catheter placement required 7 +/- 2 min in Group S and 5 +/- 2 min in Group C (P = 0.056). A significantly shorter onset time of both sensory and motor blocks was noted in Group S. No difference in quality of pain relief at rest and during motion was reported between the groups. Median (range) local anesthetic consumption during the first 48 h after surgery was 239 mL (175-519 mL) and 322 mL (184-508 mL) in Groups S and C, respectively (P = 0.002). Rescue opioid analgesia was required by 12 (25%) and 28 (58%) patients in Groups S and C, respectively (P = 0.002). We conclude that the use of a stimulating catheter results in shorter onset time of posterior popliteal sciatic nerve block, similar pain relief with reduced postoperative consumption of local anesthetic solution, and less rescue opioid consumption. IMPLICATIONS: This prospective, randomized, blind investigation demonstrated that the use of a stimulating catheter for continuous posterior popliteal sciatic nerve block resulted in shorter onset time of sensory and motor blocks and less local anesthetic consumption and need for rescue pain medication after elective orthopedic foot surgery compared with blind catheter advancement.