Cell-autonomous regulation of hematopoietic stem cell cycling activity by ATP.

Extracellular nucleotides regulate many cellular functions through activation of purinergic receptors in the plasma membrane. Here, we show that in hematopoietic stem cell (HSC), ATP is stored in vesicles and released in a calcium-sensitive manner. HSC expresses ATP responsive P2X receptors and in vitro pharmacological P2X antagonism restrained hematopoietic progenitors proliferation, but not myeloid differentiation. In mice suffering from chronic inflammation, HSCs were significantly expanded and their cycling activity was sensitive to treatment with the P2X antagonist periodate-oxidized 2,3-dialdehyde ATP. Our results indicate that ATP acts as an autocrine stimulus in regulating HSCs pool size.

Postoperative pain treatment SIAARTI Recommendations 2010. Short version.

The aim of these recommendations is the revision of data published in 2002 in the "SIAARTI Recommendations for acute postoperative pain treatment". In this version, the SIAARTI Study Group for acute and chronic pain decided to grade evidence based on the "modified Delphi" method with 5 levels of recommendation strength. Analgesia is a fundamental right of the patient. The appropriate management of postoperative pain (POP) is known to significantly reduce perioperative morbidity, including the incidence of postoperative complications, hospital stay and costs, especially in high-risk patients (ASA III-V), those undergoing major surgery and those hospitalized in a critical unit (Level A). Therefore, the treatment of POP represents a high-priority institutional objective, as well as an integral part of the treatment plan for "perioperative disease", which includes analgesia, early mobilization, early enteral nutrition and active physiokinesitherapy (Level A). In order to improve an ACUTE PAIN SERVICE organization, we recommend: --a plan for pain management that includes adequate preoperative evaluation, pain measurement, organization of existing resources, identification and training of involved personnel in order to assure multimodal analgesia, early mobilization, early enteral nutrition and active physiokinesitherapy (Level A); --the implementation of an Acute Pain Service, a multidisciplinary structure which includes an anesthetist (team coordinator), surgeons, nurses, physiotherapists and eventually other specialists; --referring to high-quality indicators in establishing an APS and considering the following key points in its organization (Level C): --service adoption; --identifying a referring anesthetist who is on call 24 hours a day; --patient care during the night and weekend; --sharing, drafting and updating written therapeutic protocols; --continuous medical education; --systematic pain assessment; --data collection regarding the efficacy and safety of the implemented protocols; --at least one audit per year. --a preoperative evaluation, including all the necessary information for the management of postoperative analgesia (Level C); --to adequately inform the patient about the risks and benefits of drugs and procedures used to obtain the maximum efficacy from the administered treatments (Level D). We describe pharmacological and loco-regional techniques with special attention to day surgery and difficult populations. Risk management pathways must be the reference for early identification and treatment of adverse events and chronic pain development.

Transcutaneous carbon dioxide monitoring in spontaneously breathing, nonintubated patients in the early postoperative period.

BACKGROUND: The authors investigated the accuracy of transcutaneous capnometry (TcPCO(2)) in estimating arterial blood carbon dioxide partial pressure (PaCO(2)) during spontaneous breathing in patients admitted to our surgical intensive care unit (ICU). METHODS: Serial TcPCO(2) and PaCO(2) measurements were taken in stable patients undergoing postoperative monitoring after major abdominal, vascular, or thoracic surgery. Patients were enrolled 12 hours after extubation. Exclusion criteria were pulmonary dysfunction, hemodynamic instability, or anemia. Linear regression, mixed models, and Bland-Altman analyses were used to compare accuracy and correlation between the two variables. Data are presented as means (95% confidence intervals). RESULTS: PaCO(2) values ranged between 26 mmHg and 52 mmHg. Mean values for TcPCO(2) and PaCO(2) were 35.3 (33.8-36.8) mmHg and 39.2 (37.6-40.7) (P<0.001). Bland-Altman analysis showed a bias of -3.8 (-5.1-2.5) mmHg with upper and lower limits of agreement of 5.6 (3.4-7.9) mmHg and -13.3 (-15.6 -11.1) mmHg, respectively. Thirty-one (55.4%) measurements disagreed by 3 mmHg or more. Linear mixed model analysis with adjustment for repeated measurements showed low correlation (r=0.63; P<0.0005). There were small but significant differences between patients in the correlation coefficient (P=0.04). CONCLUSION: TcPCO(2) showed moderate bias with wide limits of agreement when compared to PaCO(2) in our patients. The regression model showed low correlation of the measurements when adjusting for repeated measurements and between-subject variances. TcPCO(2) may not provide an accurate quantitative estimation of PaCO(2) in stable, spontaneously breathing, nonintubated patients in the early postoperative period.

A prospective, randomized, double-blind comparison between parecoxib and ketorolac for early postoperative analgesia following nasal surgery.

BACKGROUND: The aim of this prospective, randomized, double-blind study was to compare the efficacy of parecoxibfor postoperative analgesia after endoscopic turbinate and sinus surgery, with the non-selective non-steroid anti-inflammatory drug (NSAID), ketorolac. METHODS: A total of 50 patients with an ASA physical status I-II, receiving functional endoscopic sinus surgery (FESS) and endoscopic turbinectomy after local infiltration with 1% mepivacaine, were randomly assigned to receive intravenous administration of either 40 mg parecoxib (N.=25) or 30 mg ketorolac (N.=25), 15 min before the discontinuation of anaesthesia and then every 8 h postoperatively. A blinded observer recorded the incidence and severity of pain upon admission to the postanesthesia care unit (PACU), as well as 10, 20, and 30 min after PACU admission. Thereafter, observations continued every 1 h for the first 6 h, and then 12 h and 24 h after surgery. RESULTS: The area under the curve of the visual analogue scale (AUCVAS) calculated during the study period was 635 (26-1 413) in the Parecoxib group and 669 (28-1 901) in the Ketorolac group (P=0.54). Rescue morphine analgesia was required by 12 patients (48%) in the Parecoxib group and 11 patients (44%) in the Ketorolac group (P<0.05); while mean morphine consumption was 5 +/- 2.5 mg and 5 +/- 2.0 mg in Ketorolac and Parecoxib groups, respectively (P<0.05). No differences in the incidence of side effects were recorded between the two groups. Patient satisfaction was similarly high in both groups, and all patients were discharged uneventfully 24 h after surgery. CONCLUSION: In patients undergoing endoscopic nasal surgery and local infiltration with 1% mepivacaine, parecoxib administered before discontinuing general anesthesia is as effective in treating early postoperative pain as ketorolac.

Effects of ultrasound guidance on the minimum effective anaesthetic volume required to block the femoral nerve.

BACKGROUND: We tested the hypothesis that ultrasound guidance may reduce the minimum effective anaesthetic volume (MEAV50) of ropivacaine 0.5% required to block the femoral nerve compared with nerve stimulation guidance. METHODS: After standard premedication and sciatic nerve block were given, 60 patients undergoing knee arthroscopy were randomly allocated to receive a femoral nerve block with ropivacaine 0.5% using either nerve stimulation (group NS, n = 30) or ultrasound (group US, n = 30) guidance. The volume of the injected solution was varied for consecutive patients based on an up-and-down staircase method according to the response of the previous patient. The initial volume was 12 ml. A double-blinded observer evaluated the occurrence of complete loss of pinprick sensation in the femoral nerve distribution, with concomitant block of the quadriceps muscle: positive or negative responses within 30 min after the injection determined a 3 ml decrease or increase for the next patient, respectively. RESULTS: The mean (sd) MEAV50 for femoral nerve block was 15 (4) ml (95% CI, 7-23 ml) in group US and 26 (4) ml (95% CI, 19-33 ml) in group NS (P = 0.002). The effective dose in 95% of cases (ED95) calculated with probit transformation and logistic regression analysis was 22 ml (95% CI, 13-36 ml) in group US, and 41 ml (95% CI, fs 24-66 ml) in group NS. CONCLUSIONS: Ultrasound guidance provided a 42% reduction in the MEAV of ropivacaine 0.5% required to block the femoral nerve as compared with the nerve stimulation guidance.

Ipsilateral shoulder pain after thoracotomy surgery: a prospective, randomized, double-blind, placebo-controlled evaluation of the efficacy of infiltrating the phrenic nerve with 0.2%wt/vol ropivacaine.

BACKGROUND: The aim of this prospective, randomized, double-blind, placebo-controlled study was to evaluate the efficacy of phrenic nerve infiltration with ropivacaine 0.2% on the incidence and severity of ipsilateral shoulder pain after thoracotomy in patients receiving continuous thoracic epidural analgesia. METHODS: Fifty ASA physical status II-III patients, receiving thoracic epidural analgesia for post-thoracotomy pain, were randomly allocated to receive infiltration of the ipsilateral phrenic nerve with either ropivacaine 0.2% 10 mL (ropivacaine, n = 25), or saline 0.9% (control, n = 25) just before lung expansion and chest closure. A blinded observer recorded the incidence and severity of ipsilateral shoulder pain 6, 12, 24, 36 and 48 h after surgery. Postoperative respiratory function was also evaluated with blood gas analyses. RESULTS: The cumulative incidences of ipsilateral shoulder pain during the first 24 h after surgery were 8/25 in the ropivacaine and 16/25 in the control groups (P = 0.047), with median (range) onset times for shoulder pain of 2 (2-24) h with ropivacaine and 0.5 (0.5-24) h in controls (P = 0.005). No differences were reported on the second postoperative day. The areas under the curves of the amount of pain over time were 0 (0-2760) mm h for the ropivacaine and 350 (0-1900) mm h for the control groups (P = 0.06). Postoperatively, similar reductions in indices of oxygenation were observed in both groups. CONCLUSIONS: Phrenic nerve infiltration with ropivacaine 0.2% 10 mL reduced the incidence and delayed the onset of ipsilateral shoulder pain during the first 24 h after open lung resection, with no clinically relevant effects on respiratory function.

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.

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.

Pain relief and motor function during continuous interscalene analgesia after open shoulder surgery: a prospective, randomized, double-blind comparison between levobupivacaine 0.25%, and ropivacaine 0.25% or 0.4%.

BACKGROUND AND OBJECTIVES: To compare pain relief and motor impairment of 0.25% levobupivacaine with either an equivalent (0.25%) or equipotent (0.4%) concentration of ropivacaine for continuous interscalene block after open shoulder surgery. METHODS: Seventy-two adult patients scheduled for elective major shoulder surgery received an interscalene injection of mepivacaine 1.5% 30 mL followed by 24 h patient-controlled interscalene analgesia (basal infusion rate: 5 mL h-1; incremental bolus: 2 mL; lockout period: 10 min; maximum boluses per hour: 4) with either 0.25% levobupivacaine (n = 24), 0.25% ropivacaine (n = 24) or 0.4% ropivacaine (n = 24). A blinded observer recorded the evolution of pain relief and recovery of motor block during the first 24 h. Motor function was assessed as the maximum pressure developed while squeezing a sphygmomanometer cuff with the blocked hand. The reduction from preoperative values was considered as an index of motor impairment. RESULTS: No differences were reported among the three groups in the quality of postoperative analgesia. The number of incremental patient-controlled interscalene analgesia doses, total volume of local anaesthetic infused during the 24-h patient-controlled interscalene analgesia, and number of rescue ketoprofen analgesia were higher in the ropivacaine 0.25% group than in the other two groups (P = 0.0005). The hand strength recovered to >or=90% of baseline values within the first 24 h of infusion in all groups, without differences among the three groups. CONCLUSION: When providing patient-controlled interscalene analgesia after open shoulder surgery 0.25% levobupivacaine and 0.4% ropivacaine performed equally in terms of pain relief, motor block and number of patient-controlled boluses required, while patients receiving 0.25% ropivacaine needed significantly more boluses and rescue analgesia to control their pain.

A prospective, randomized, blinded comparison between continuous thoracic paravertebral and epidural infusion of 0.2% ropivacaine after lung resection surgery.

BACKGROUND: The aim of this prospective, randomized, blinded study was to compare analgesic efficacy of continuous paravertebral and epidural analgesia for post-thoracotomy pain. METHODS: Forty-two ASA physical status II-III patients undergoing lung resection surgery were randomly allocated to receive post-thoracotomy analgesia with either a thoracic epidural (group EPI, n = 21) or paravertebral (group PVB, n = 21) infusion of 0.2% ropivacaine (infusion rate: 5-10 mL h-1). The degree of pain at rest and during coughing, haemodynamic variables and blood gas analysis were recorded every 12 h for the first 48 h. RESULTS: The area under the curve of the visual analogue pain score during coughing over time was 192 (60-444) cm h-1 in group EPI and 228 (72-456) cm h-1 in group PVB (P = 0.29). Rescue morphine analgesia was required in four patients of group EPI (19%) and five patients of group PVB (23%) (P = 0.99). The PaO2/FiO2 ratio reduced significantly from baseline values in both groups without between-group differences. The median (range) percentage reduction of systolic arterial pressure from baseline was -9 (0 to -9)% in group PVB and -17 (0 to -38)% in group EPI (P = 0.02); while clinically relevant hypotension (systolic arterial pressure decrease >30% of baseline) was observed in four patients of group EPI only (19%) (P = 0.04). Patient satisfaction with the analgesia technique was 8.5 (8-9.8) cm in group EPI and 9 (7.5-10) cm in group PVB (P = 0.65). CONCLUSIONS: Continuous thoracic paravertebral analgesia is as effective as epidural blockade in controlling post-thoracotomy pain, but is associated with less haemodynamic effects.

New technology for noninvasive brain monitoring: continuous cerebral oximetry.

Although the central nervous system is the primary endpoint of most general anesthetics, it is still the least monitored organ in clinical anesthesiology. In the last decade, technological research has expanded the application of near-infrared spectroscopy to allow continuous, non-invasive, and bedside monitoring of cerebral oxygen saturation (rSO(2)) through the scalp and skull, providing accurate information on the balance between brain oxygen supply and demand. The aim of this review is to provide an overview on relevant technological issues of cerebral oximetry, describe a systematic approach to its use, and summarize current information on its possible impact on our daily practice. We reviewed studies published on peer-reviewed journals about technological development and clinical application of rSO(2) monitoring in different fields of application to clinical practice. Due to the wide patient-to-patient variability of baseline rSO(2) values in each patient the baseline value should be determined before inducing general anesthesia, and cerebral ischemia is related more to the changes from baseline than to the absolute value: a reduction of 20% from baseline is usually accepted as clinical threshold of cerebral ischemia. If baseline rSO(2) is lower than 50% the critical threshold should be reduced to 15%. Routine use of rSO(2) monitoring in patients undergoing cardiac surgery to guide the anesthesia plan has been demonstrated to improve patient outcome and shorten hospital stay. However, rSO(2) monitoring does not seem to provide information accurate enough to indicate the placement of a Javid's shunt during carotid endarterectomy. In patients with neurological pathology or head trauma rSO(2) monitoring has been reported accurate enough in detecting early changes in cerebral blood flow that might result in cerebral ischemia. In aged patients undergoing major abdominal surgery rSO(2) monitoring to guide the anesthesia plan has been reported to reduce the exposition to cerebral ischemia with less effects on cognitive decline and shorter hospital stay. In conclusion several clinical conditions routinely encountered in our daily practice have the potential to disrupt the balance between the brain oxygen supply and demand, exposing to the risk of intraoperative cerebral ischemia. These alterations in brain oxygen balance remain totally undiagnosed if we do not specifically monitor it; while the possibility of monitoring regional cerebral oxygen saturation through a simple and totally non-invasive device has the potential for optimizing our anesthesia plan to the real needs of our main targeted organ: the brain.

Opioid-related side-effects after intrathecal morphine: a prospective, randomized, double-blind dose-response study.

BACKGROUND AND OBJECTIVE: The aim of this prospective, randomized, double-blind investigation was to assess the dose-effect characteristics of postoperative nausea and vomiting after intrathecal administration of small doses of morphine (from 0.015 to 0.25 mg) in opioid-naïve, non-surgical patients. METHODS: With Ethic Committee approval and written informed consent 144 opioid-naïve patients suffering from non-cancerous chronic back-pain, and receiving intrathecal morphine as diagnostic test for their chronic pain, were randomly allocated to receive intrathecal injection of 0.015 mg (Group I, n=25), 0.03 mg (Group II, n=30), 0.06 mg (Group III, n=31) or 0.25 mg (Group IV, n=33) morphine. The control group consisted in 25 further patients not included in the dose-effect study and receiving a placebo injection of normal saline in the interspinous ligament. A blinded observer recorded the occurrence of pruritus, nausea, vomiting, urinary retention and respiratory depression (respiratory rate<6 bpm) at 2, 4 and 24 h after injection. RESULTS: Clinically significant pain relief was observed in all patients receiving intrathecal morphine but only six patients (25%) of the control group (P=0.0005). The incidence of pruritus was lower in patients of Groups III (6%) and IV (3%) than in Groups I (12%) and II (20%) (P=0.002). The incidence of nausea and vomiting was higher at 2- and 4-h observation times, and decreased 24 h after intrathecal injection. Surprisingly, nausea was more frequent in Groups I (56%) and II (50%) than in Groups III (33%) and IV (24%) (P=0.0005). Vomiting was higher in patients receiving morphine than in control group, but without differences among the four doses. No urinary retention was observed in the control group, while 2 h after intrathecal injection urinary retention was observed in 20-40% of cases, and decreased to less than 10% 24 h after spinal injection without differences among the four doses. CONCLUSIONS: The onset and incidence of minor opioid-related side-effects after intrathecal morphine administration do not depend on its dose, occurring with even very small doses of morphine. Accordingly, they can be considered as a patient-dependent effect of the drug, suggesting the presence of a primary dose-independent excitatory component that might be related to the theory of the bimodal activation of opioid receptors. The very low incidence major respiratory depression prevents us from drawing any conclusion about the dose-effect relationship for this side-effect, and further properly powered studies should be advocated to evaluate major respiratory depression after spinal morphine.

The effect of adding nitrous oxide on MAC of sevoflurane combined with two target-controlled concentrations of remifentanil in women.

BACKGROUND AND OBJECTIVE: The aim of this prospective, randomized, double-blind study was to determine the effects of adding nitrous oxide on sevoflurane requirement for blunting sympathetic responses after surgical incision combined with two different target-controlled concentrations of remifentanil (1 and 3 ng mL(-1)) in female. METHODS: 102 female patients, aged 20-50 yr, ASA I, undergoing general anaesthesia for elective abdominal surgery were enrolled and randomly allocated to receive sevoflurane anaesthesia alone (Group A, n=53), or with the addition of 60% nitrous oxide (Group N, n=49). Patients of both groups were further assigned to receive a target-controlled remifentanil infusion with an effect-site concentration of either 1 ng mL(-1) (Group N1, n=27; Group A1, n=30), or 3 ng mL(-1) (Group N3, n=22; Group A3, n=23). Sympathetic responses to surgical incision were determined after a 20-min period of stable end-tidal sevoflurane and target-controlled remifentanil concentrations. Predetermined end-tidal sevoflurane concentrations and minimum alveolar concentration (MAC) for each group were determined using an up-and-down sequential allocation technique. RESULTS: The MAC of sevoflurane was 3.96% (95% confidence interval, CI95: 3.69-4.23%) in Group A1 and 1.2% (CI95: 0.9-1.3%) in Group N1 (P < 0.01), while in Groups A3 and N3 the MAC of sevoflurane was 0.36% (CI95: 0.24-0.47%) and 0.18% (CI95: 0.1-0.3%), respectively (P < 0.05). CONCLUSION: Adding 60% nitrous oxide reduces the MAC of sevoflurane by 70% when using a remifentanil concentration of 1 ng mL(-1) and 50% when using a remifentanil concentration of 3 ng mL(-1).

Sciatic nerve block with 0.5% levobupivacaine, 0.75% levobupivacaine or 0.75% ropivacaine: a double-blind, randomized comparison.

BACKGROUND AND OBJECTIVE: This prospective, randomized, double-blind study was conducted to evaluate the onset time and duration of sciatic nerve block produced with 0.5% levobupivacaine, 0.75% levobupivacaine and 0.75% ropivacaine. METHODS: Forty-five healthy patients undergoing hallux valgus repair were randomly allocated to receive sciatic nerve block with levobupivacaine 0.5% (n=15), levobupivacaine 0.75% (n=15) or ropivacaine 0.75% 20 mL (n=15). A femoral nerve block was also performed with mepivacaine 2% 15 mL to cover pain related to the thigh tourniquet. A blinded observer recorded the onset time and duration of sciatic nerve block. RESULTS: The median (range) onset time was 5 (5-40) min with 0.75% levobupivacaine, 30 (5-60) min with 0.5% levobupivacaine and 20 (5-50) min with 0.75% ropivacaine (P = 0.02 and P = 0.12, respectively). Mean (25-75 percentiles) first request for pain medication occurred after 13 (11-14) h with 0.75% ropivacaine, 18 (15-19) h with 0.75% levobupivacaine and 16 (13-20) h with 0.5% levobupivacaine (P = 0.002 and P = 0.002, respectively). Rescue tramadol after surgery was required by three patients in the 0.75% levobupivacaine group, eight patients in the 0.5% levobupivacaine group and nine patients in the 0.75% ropivacaine group (P = 0.05). CONCLUSIONS: We conclude that 0.75% levobupivacaine provides a shorter onset time than 0.5% levobupivacaine and a longer duration of postoperative analgesia than both 0.5% levobupivacaine and 0.75% ropivacaine with reduced need for rescue analgesia after surgery.

Epidural block does not worsen oxygenation during one-lung ventilation for lung resections under isoflurane/nitrous oxide anaesthesia.

BACKGROUND AND OBJECTIVES: The aim of this prospective, randomized, controlled clinical study was to evaluate the effects of thoracic epidural anaesthesia combined with isoflurane/nitrous oxide anaesthesia on intraoperative oxygenation during one-lung ventilation for lung resections. METHODS: Forty patients were randomly allocated to receive general anaesthesia maintained with isoflurane/nitrous oxide (group General, n = 20) or the same anaesthetic combined with thoracic epidural anaesthesia (group Integrated, n = 20). All patients were mechanically ventilated with the same settings (FiO2 = 0.5; VT = 9 mL kg(-1); inspiratory: expiratory time = 1:1; inspiratory pause = 10%). Effects on oxygenation were evaluated by determining the changes in PaO2/FiO2 ratio at 10, 30, 45 and 60 min of one-lung ventilation as compared to values obtained after induction of anaesthesia (supine, two-lung ventilation). RESULTS: The PaO2/FiO2 ratio was decreased in both groups during one-lung ventilation until the end of surgery. No differences were found at any observation time between the groups. Ventilation with 100% oxygen because of SpO2 decrease <92% was required in nine patients of group General (45%) and in eight patients of group Integrated (40%) (P = 0.64). Manual re-inflation of the operated lung was required in one patient of group General only (P = 0.99). Heart rate was lower in group Integrated than in group General throughout the study. No differences between the two groups in mean arterial pressure were observed. CONCLUSIONS: Adding a thoracic epidural block to isoflurane/nitrous oxide anaesthesia during one-lung ventilation for lung resections does not result in clinically relevant detrimental effects on intraoperative oxygenation.

0.2% ropivacaine with or without sufentanil for patient-controlled epidural analgesia after anterior cruciate ligament repair.

AIM: The aim of this prospective, randomized, double-blind study was to evaluate the effects of adding 0.5 microg/ml sufentanil to 0.2% ropivacaine for patient controlled epidural analgesia (PCEA) on the quality of postoperative pain control in patients undergoing anterior cruciate ligament (ACL) reconstruction. METHODS: Twenty ASA physical status I-II patients, scheduled to have elective ACL repair were studied. Combined spinal-epidural anesthesia was performed at the L3-L4 or L4-L5 interspace using a needle-through-needle technique. Spinal anesthesia was induced with 10 mg of 0.5% hyperbaric bupivacaine. Postoperative epidural analgesia was started at the end of surgery using a continuous epidural infusion of 0.2% ropivacaine alone (n=10) or 0.2% ropivacaine/0.5 mg mL(-1) sufentanil (n=10). The degree of pain was evaluated at 1, 8, 16, 24 and 48 hours after surgery; at the same observation times the degree of motor block, sedation, oxygen saturation, total consumption of PCEA solution and incremental doses given to the patient were also recorded. RESULTS: No differences in the quality of intraoperative anesthesia was observed, and in no case general anesthesia was required to complete surgery. Patients receiving the combination of ropivacaine and sufentanil showed lower levels of VAS from 16 hours after surgery as compared with ropivacaine group (P=0.02). However, no differences in the degree of pain were observed between the 2 groups during continuous passive mobilization. CONCLUSION: Adding 0.5 microg/ml sufentanil to 0.2% ropivacaine for patient controlled epidural analgesia improved pain control at rest but did not result in significant improvement of postoperative analgesia during continuous passive mobilization.

A multicenter survey on anaesthesia practice in Italy.

AIM: To achieve more information on anaesthesia practice in Italy. METHODS: One questionnaire was completed for every anaesthetic procedure performed during the last week of June 1999 in 162 public hospitals selected in the northern, central and southern parts of Italy. RESULTS: A total of 12 263 anaesthetic procedures were performed during the study week in participating hospitals, extrapolating to 4 905200 anaesthetic procedures performed in Italy in 1999 (95% confidence interval, (+/-245000), with an annual rate of 8.5 anaesthetic procedures per 100 population. Children represented 12%, adults 60%, and elderly patients 28% of all studied patients. Emergency procedures were performed in 14% of cases; only 14% of cases were outpatients, but 31% of patients were discharged within 48 h after surgery. General anaesthesia was used in 65% of cases (45% volatile and 20% intravenous anaesthesia), regional anaesthesia in 24%, local anaesthesia in 8.8% and monitored anaesthesia care in 2.2%. No differences in the distribution of anaesthesia techniques were observed according to the geographic region or hospital size. CONCLUSION: Some organizational problems still remain to be implemented, including the development of proper preoperative evaluation clinics and postanaesthesia care units, especially in bigger hospitals with more than 1 000 beds.

Total intravenous anesthesia, spinal anesthesia or combined sciatic-femoral nerve block for outpatient knee arthroscopy.

AIM: The aim of this study was to compare efficacy, efficiency and surgeon's satisfaction of total intravenous anesthesia with propofol and remifentanil with those of spinal or peripheral nerve blocks for outpatient knee arthroscopy. METHODS: One hundred and twenty patients undergoing elective outpatient knee arthroscopy were randomly allocated to receive total intravenous anesthesia with propofol and remifentanil (40), combined sciatic-femoral nerve block (40), or spinal anesthesia (40). Preparation times, surgeon's satisfaction, and discharge times with the 3 anesthesia techniques were measured. Anesthesia-related costs were also compared based on costs of drugs, disposable materials, and anesthesia and nurse staff. RESULTS: Preparation time was 13 min (8-22 min) with general anesthesia, 15 min (5-30 min) with spinal anesthesia and 15 min (5-25 min) with sciatic-femoral blocks (p=0.006). Surgeon's satisfaction was similar in the 3 groups, but 17 patients receiving peripheral nerve block (42%) and 12 receiving spinal anesthesia (30%) by-passed the postanesthesia care unit after surgery as compared with only 2 general anesthesia patients (5%) (p=0.01). Discharge from the postanesthesia care unit required 5 min (5-20 min) after peripheral block as compared with 15 min (5-25 min) with spinal and 15 min (5-80 min) with general anesthesia (p=0.005); however, stay in the Day-Surgery Unit was shorter after general anesthesia [170 (100-400) min] than peripheral [265 (110-485) min] or spinal blocks [230 (95-800) min] (p=0.026). Urinary retention was reported in 3 spinal patients only (8%) (p=0.03). CONCLUSION: Regional anesthesia techniques reduce the rate of admission and the duration of stay in the postanesthesia care unit as compared with general anesthesia. Peripheral rather than spinal nerve blocks should be preferred to minimise the risk for urinary retention.

Prilocaine or mepivacaine for combined sciatic-femoral nerve block in patients receiving elective knee arthroscopy.

AIM: The aim of this study was to evaluate the onset time of surgical block, recovery of motor function and duration of post-operative analgesia of combined sciatic-femoral nerve block performed with either mepivacaine or prilocaine. METHODS: With Ethical Committee approval and written informed consent, 30 ASA physical status I-II patients, undergoing elective arthroscopic knee surgery, received a combined sciatic-femoral nerve block with 30 ml of either 2% mepivacaine (n=15) or 1% prilocaine (n=15). An independent observer recorded the onset time of sensory and motor blocks, the need for intraoperative analgesia supplementation, recovery of motor function, and first request of post-operative pain medication. RESULTS: Onset time of nerve block required 15+/-5 min with prilocaine and 12+/-7 min with mepivacaine (p=0.33). No patient required general anesthesia to complete surgery; 3 patients receiving prilocaine (20%) and 2 patients receiving mepivacaine (13%) required 0.1 mg fentanyl intravenously to complete surgery (p=0.99). Recovery of motor function and first request of post-operative pain medication occurred after 238+/-36 min and 259+/-31 min with prilocaine, and 220+/-48 min and 248+/-47 min with mepivacaine (p=0.257 and p=0.43, respectively). Patient satisfaction was good in all studied patients. CONCLUSION: Prilocaine 1% provides adequate sensory and motor block for arthroscopic knee surgery, with a clinical profile similar to that produced by 2% mepivacaine, and may be a good option for surgical procedures of intermediate duration and not associated with severe postoperative pain.