The Impact of Regional Anesthesia in Masking Acute Compartment Syndrome after Limb Trauma.

Regional anesthesia has shown to be successful in controlling major pain in trauma patients. However, the possibility of masking acute compartment syndrome (ACS) after peripheral nerve blocks for limb injuries is still controversially discussed. Therefore, we aimed to summarize the current literature regarding this topic to shed light on the impact of peripheral regional anesthesia on the diagnosis of ACS in trauma patients. We searched Pubmed, Google Scholar and the Cochrane Library for literature following the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines. The analysis of these reports was included in the context of the current literature concerning this topic. We found no (randomized) studies, and only six case reports dealing with the impact of peripheral nerve blocks and ACS in patients after a limb trauma met our criteria and were included in our review. Only one reported a delay in the diagnosis of ACS. In most of the cases (5 of 6), the breakthrough pain, despite the nerve block, proved to be a good indicator of a developing ACS. However, despite some narrative articles about the topic including some recommendations about the possibly safe use of regional anesthesia techniques for limb trauma, there is still no international consensus and only one national guideline focusing on the possibly safe use of peripheral nerve blocks in trauma patients at risk of ACS. After reviewing the respective literature, we consider that intra-articular analgesia, sensory blocks, fascial plane blocks and low-concentration continuous peripheral nerve blocks are effective for analgesia and a low-risk analgesia tool for trauma and postsurgical patients at risk of ACS due to the fact that they do not lead to a dense block. Finally, we summarized suggestions based on the results of the literature for the different regional anesthesia modalities in these patients in a table to facilitate the use of these techniques.

Effects of enhanced adsorption haemofiltration versus haemoadsorption in severe, refractory septic shock with high levels of endotoxemia: the ENDoX bicentric, randomized, controlled trial.

BACKGROUND: Endotoxin adsorption is a promising but controversial therapy in severe, refractory septic shock and conflicting results exist on the effective capacity of available devices to reduce circulating endotoxin and inflammatory cytokine levels. METHODS: Multiarm, randomized, controlled trial in two Swiss intensive care units, with a 1:1:1 randomization of patients suffering severe, refractory septic shock with high levels of endotoxemia, defined as an endotoxin activity ≥ 0.6, a vasopressor dependency index ≥ 3, volume resuscitation of at least 30 ml/kg/24 h and at least single organ failure, to a haemoadsorption (Toraymyxin), an enhanced adsorption haemofiltration (oXiris) or a control intervention. Primary endpoint was the difference in endotoxin activity at 72-h post-intervention to baseline. In addition, inflammatory cytokine, vasopressor dependency index and SOFA-Score dynamics over the initial 72 h were assessed inter alia. RESULTS: In the 30, out of 437 screened, randomized patients (10 Standard of care, 10 oXiris, 10 Toraymyxin), endotoxin reduction at 72-h post-intervention-start did not differ among interventions (Standard of Care: 12 [1-42]%, oXiris: 21 [10-51]%, Toraymyxin: 23 [10-36]%, p = 0.82). Furthermore, no difference between groups could be observed neither for reduction of inflammatory cytokine levels (p = 0.58), nor for vasopressor weaning (p = 0.95) or reversal of organ injury (p = 0.22). CONCLUSIONS: In a highly endotoxemic, severe, refractory septic shock population neither the Toraymyxin adsorber nor the oXiris membrane could show a reduction in circulating endotoxin or cytokine levels over standard of care. Trial registration ClinicalTrials.gov. NCT01948778. Registered August 30, 2013. https://clinicaltrials.gov/study/NCT01948778.

Continuous interscalene analgesia with ropivacaine 0.2% versus ropivacaine 0.3% after open rotator cuff repair: the effects on postoperative analgesia and motor function.

BACKGROUND: Interscalene analgesia is a recognized technique for the management of postoperative pain after major shoulder surgery. The most effective local anesthetic concentration in this setting is still controversial. In this study, we compared the analgesia and side effects of a continuous infusion of ropivacaine 0.2% and 0.3% administered through an interscalene catheter for the first 48 hours after surgery. METHODS: Eighty consecutive patients scheduled for elective open rotator cuff repair were randomized into 2 groups to receive a continuous infusion of either ropivacaine 0.2% or ropivacaine 0.3% for 48 hours at a rate of 14 mL/h through an interscalene catheter after a preoperative bolus of 40 mL ropivacaine 0.5% in all patients. Pain score (visual analog scale 0-100), intensity of motor block, quality of sleep during the first postoperative night, morphine consumption, side effects, and patient satisfaction were assessed by an anesthesiologist masked to treatment group. RESULTS: Total morphine consumption was significantly reduced in group 0.3% (12 vs 30 mg). Quality of sleep was significantly better in group 0.3% (4% vs 27% of awakening during the first postoperative night). Handgrip strength, visual analog scale scores, and side effects were similar in both groups. CONCLUSION: The use of ropivacaine 0.3% through an interscalene catheter for the first 48 hours after open rotator cuff repair provided a significant reduction of morphine consumption and a better sleep quality for the first postoperative night without increasing the intensity of motor block or side effects.

Subacromial pressures vary with simulated sleep positions.

HYPOTHESIS: Subacromial impingement is one of the underlying factors of rotator cuff pathologies and is linked to increased subacromial pressures. Because humans spend about one-third of their life sleeping, we hypothesized that distinct shoulder positions while sleeping may considerably influence nocturnal subacromial pressures. Consequently, atrophy and rupture can affect tendon healing after rotator cuff repair, thus potentially discrediting the outcome of surgery. MATERIALS AND METHODS: We determined the subacromial pressures acting on the rotator cuff in the 4 most common sleep positions and related these pressures to the mean arterial blood pressure and physical examination findings in 20 healthy volunteers. RESULTS: Subacromial pressures were significantly lower in participants sleeping preferably in a supine position than in participants sleeping in side or prone positions (P < .005). DISCUSSION: As tendon perfusion is crucial for tendon-to-bone healing during postoperative physical therapy after rotator cuff reconstruction and for prevention of additional damage to healthy or already torn cuffs, potential clinical relevance may emerge from the present study. CONCLUSION: Distinct shoulder positions considerably influence subacromial pressures. Our findings may be considered in physiotherapeutic concepts after rotator cuff surgery.

The beach chair position for shoulder surgery in intravenous general anesthesia and controlled hypotension: Impact on cerebral oxygenation, cerebral blood flow and neurobehavioral outcome.

STUDY OBJECTIVES: The aim of this study was to assess the impact of intravenous general anesthesia and controlled hypotension on cerebral saturation (rScO2), cerebral blood flow measured as middle cerebral artery blood flow velocity (Vmax MCA) and neurobehavioral outcome in patients scheduled for shoulder surgery in beach chair position. DESIGN: Prospective, assessor-blinded observational study. SETTING: University hospital, shoulder surgery operating room. PATIENTS: Forty ASA I-II patients scheduled for shoulder surgery in beach chair position and controlled hypotension. INTERVENTIONS: Neurological and neurobehavioral tests were performed prior and the day after surgery. The baseline data for near-infrared spectroscopy, bispectral index, cerebral blood flow, PaCO2 and invasive blood pressure (radial artery) were taken prior anesthesia and after anesthesia induction, after beach chair positioning and all 20 min after surgery start until discharge of the patient. MEASUREMENTS: Neurological and neurobehavioral tests, cerebral saturation (rScO2) using near-infrared spectroscopy, BIS, cerebral blood flow using Doppler of the middle cerebral artery (Vmax MCA), PaCO2 and invasive blood pressure assessed at heart and at the external acoustic meatus level. MAIN RESULTS: The incidence of cerebral desaturation events (CDEs) was 25%. The blood pressure drop 5 min after beach chair position measured at the acoustic meatus level in the CDE group was higher compared to patients without CDEs (p = 0.009) as was the rScO2 (p = 0.039) and the Vmax MCA (p = 0.002). There were no neurological deficits but patients with CDEs showed a greater negative impact on neurobehavioral tests 24 h after surgery compared to patients without CDEs (p = 0.001). CONCLUSIONS: In ASA I-II patients intravenous general anesthesia and controlled hypotension in the beach chair position affects cerebral blood flow and cerebral oxygenation with impact on the neurobehavioral outcome.

Continuous extrapleural infusion of ropivacaine 0.2% after cardiovascular surgery via the lateral thoracotomy approach.

OBJECTIVE: The pharmacokinetics of ropivacaine 0.2% were evaluated during a 48-hour continuous extrapleural infusion with 2 different infusion rates in patients undergoing cardiovascular surgery. The hypotheses that no toxic plasma concentrations of ropivacaine would be reached and that proportionality exists among plasma concentrations and dosage used were tested. DESIGN: A prospective, randomized, nonblinded study. SETTING: The investigation was performed as a single-center study in the Division of Cardiovascular Anesthesia, University Hospital of Zurich, in Switzerland. PARTICIPANTS: Seventeen consenting adults scheduled for elective cardiovascular surgery, with or without extracorporeal bypass, via the lateral thoracotomy approach were enrolled. INTERVENTIONS: For postoperative pain relief, patients were randomly assigned to receive continuous extrapleural infusion of ropivacaine 0.2% at a rate of either 6 or 9 mL/h over 48 hours. MEASUREMENTS AND MAIN RESULTS: Plasma concentrations of ropivacaine reached toxic levels (>2.2 mg/L) in 25% of cases. No proportionality of plasma concentrations of ropivacaine existed when the 2 dosing regimens were compared. CONCLUSIONS: Plasma concentrations of ropivacaine, administered at the given dose and rates during continuous extrapleural infusion, are unpredictable and may reach toxic levels in patients undergoing major cardiothoracic surgery.

Postoperative pain management following scoliosis surgery.

PURPOSE OF REVIEW: The control of pain after scoliosis surgery is a real challenge for the anesthesiologist. The first reason is that major spine surgery for correction of scoliosis deformation causes severe postoperative pain, and second that patients undergoing these operations are most often children or adolescents who are known to suffer from increased pain sensation compared with adults. RECENT FINDINGS: A multimodal postoperative pain therapy is a well established procedure to control the pain after scoliosis surgery. Recently, prospective, well controlled studies have emphasized the key role of regional techniques in this context. Epidural analgesia has shown significant benefits regarding pain score, bowel recovery and patients' satisfaction. However, different modes of epidural analgesia application have been performed. Several issues including local anaesthetic concentration and infusion rate, duration of application and number of catheters placed will be discussed. The safety concerns associated with this type of analgesia will also be emphasized. SUMMARY: Significant improvements have been made in the control of postoperative pain after correction of scoliosis deformation in recent years. The introduction of epidural analgesia has cleared the way for better analgesic techniques in this surgical context. Properly performed and assessed, the addition of epidural analgesia after scoliosis surgery is a safe and effective form of analgesia and the benefits far outweigh the risks.

Influence of skin disinfection prior removal of perineural catheter on bacterial colonization, contamination and local inflammation: a prospective randomized study.

BACKGROUND: There is a wide variation of perineural catheter (PNC) colonization rates in the literature. The impact of skin disinfection on PNC colonization and inflammation is not clear. The objective of this prospective, randomized clinical study was to investigate the influence of alcoholic skin disinfection before PNC removal on the detection of bacteria on PNC. METHODS: Two hundred patients receiving a PNC for orthopedic surgery were randomized to receive (with-group) or not (without-group) a skin disinfection with a sprayed alcoholic solution before removal of the PNC. Bacterial colonization and contamination of the PNC and clinical signs of inflammation and infection of the PNC insertion site were evaluated. Skin disinfection with a sprayed alcoholic solution and sterile removal of the distal and subcutaneous part of the PNC was performed after 72 hours or earlier if signs of infection occurred with semiquantitative culture and enrichment culture of both parts. RESULTS: Alcoholic skin disinfection before PNC removal significantly reduced bacterial colonization with a reduction from 28% to 14% and from 32% to 17% for the tip and the subcutaneous part of the PNC, respectively (P<0.05). Clinical signs of inflammation at the PNC insertion site were similar (73%) in the two groups. The detection of colonization in 54 (27%) out of 200 PNC did not correlate with clinical signs of inflammation independently of the number of bacteria isolated. Redness was noted in 71% and 68% of patients in the without- and with-alcoholic skin disinfection-group respectively. Local pain on pressure was present in 28% and 19% in the without- and with-group respectively. CONCLUSIONS: Alcoholic skin disinfection before PNC removal reduced the detection of PNC colonisation by 50%. There was no correlation between clinical signs of inflammation and PNC colonization.

Postoperative intravenous morphine consumption, pain scores, and side effects with perioperative oral controlled-release oxycodone after lumbar discectomy.

BACKGROUND: Oral opioid formulations contribute to postoperative analgesia. In this study, we evaluated the perioperative application of oral controlled-release oxycodone to reduce postoperative IV morphine consumption and opioid side effects after lumbar discectomy. METHODS: Forty patients scheduled for elective lumbar discectomy over 1 or 2 levels were included in this prospective, randomized, double-blind, placebo-controlled study. Every 12 h patients received either 20 mg oral controlled-release oxycodone or placebo, from the evening before surgery until the second postoperative morning. All patients received IV morphine via a morphine patient-controlled analgesia device for postoperative analgesia. Acetaminophen 1 g was administered to all patients every 6 h. Postoperative IV morphine consumption was assessed separately for T(0)-T(24) and T(24)-T(48). Postoperative assessments were conducted every 6 h for the first 48 h after surgery. Postoperative analgesia assessments included pain at rest, during coughing, and with motion, using a visual analog scale. Nausea, vomiting, pruritus, sedation, and bowel function were also assessed every 6 h. Patients rated their satisfaction with postoperative analgesia 72 h postoperatively. RESULTS: Postoperative IV morphine consumption was significantly reduced during T(0)-T(24) (26 +/- 10 mg vs 52 +/- 29 mg) and T(24)-T(48) (13 +/- 8 mg vs 33 +/- 18 mg) in the controlled-release oxycodone group compared with that in the placebo group. Pain scores at rest, during coughing, and with motion were significantly lower during the first 48 postoperative hours in the controlled-release oxycodone group. Postoperative nausea and vomiting were significantly reduced during the first 24 h in the controlled-release oxycodone group. Lastly, the controlled-release oxycodone group also experienced significantly earlier recovery of bowel function and had higher patient satisfaction with pain therapy. CONCLUSIONS: Perioperative oral controlled-release oxycodone reduces postoperative IV morphine consumption after lumbar discectomy while providing good analgesia with fewer side effects compared with placebo.

The immunomodulatory effect of sevoflurane in endotoxin-injured alveolar epithelial cells.

BACKGROUND: Endotoxin-induced lung injury is a useful experimental system for the characterization of immunopathologic mechanisms in acute lung injury. Although alveolar epithelial cells (AEC) are directly exposed to volatile anesthetics, there is limited information about the effect of anesthetics on these cells. In this study we investigated the effect of pretreatment with the inhaled anesthetic sevoflurane on lipopolysaccharide (LPS)-injured AEC. METHODS: AEC were incubated with 1.1 vol % sevoflurane for 0.5 h, followed by LPS stimulation for 5 h. Expression of monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1beta (MIP-1beta), macrophage inflammatory protein-2 (MIP-2), cytokine-induced neutrophil chemoattractant-1 (CINC-1), and intercellular adhesion molecule-1 (ICAM-1) was analyzed. In addition, functional tests were performed through chemotaxis and adherence assays to underline the biological relevance of the findings. RESULTS: Exposure of AEC to sevoflurane resulted in a 50% downregulation of MCP-1 protein in the sevoflurane-LPS group when compared with non-sevoflurane- LPS cells (P < 0.05). MIP-1beta concentration in LPS-stimulated cells decreased by 32% with sevoflurane (P < 0.05), MIP-2 by 29% (P < 0.05), and CINC-1 by 20% (P < 0.05). ICAM-1 protein expression was attenuated by 36% (P < 0.05). This inhibition caused substantial changes in the inflammatory response of neutrophils. 33% less chemotactic activity was seen in sevoflurane-treated LPS cells (P < 0.001) as well as 47% decreased adhesion of neutrophils to AEC (P < 0.001). CONCLUSIONS: This study shows that sevoflurane alters the LPS-induced inflammatory response, not only with respect to the expression pattern of inflammatory mediators, but also regarding the biological consequences with less accumulation of effector cells such as neutrophils.

Effect of selective experimental suprascapular nerve block on abduction and external rotation strength of the shoulder.

The relative contribution to strength of the supraspinatus and infraspinatus to abduction and external rotation is not precisely known. Optimal testing positions for clinical assessment of supraspinatus and infraspinatus function are not precisely defined. We sequentially performed electromyographically controlled, complete nerve blocks of the suprascapular nerve, first at the spinoglenoid notch, to induce complete, isolated infraspinatus palsy. The suprascapular nerve was then blocked at the scapular notch, resulting in complete supraspinatus and infraspinatus palsy in 11 volunteers. Strength of abduction in the scapular plane and of external rotation was measured at 0 degrees , 30 degrees , 60 degrees , and 90 degrees of abduction, by use of a validated, instrumented strength-measuring device. Complete isolated infraspinatus palsy was obtained in 11 volunteers and complete combined supraspinatus and infraspinatus palsy in 9. Infraspinatus palsy alone led to a loss of approximately 70% of external rotation strength and approximately 45% of abduction strength. The degree of loss of strength was not dependent on the angle of abduction. Paralysis of the infraspinatus and the supraspinatus led to a loss of external rotator strength of approximately 80% and a loss of abductor strength of approximately 75%. The loss was again independent of the angle of abduction at which the testing took place. Testing of supraspinatus and infraspinatus strength can be performed at any angle between 30 degrees and 90 degrees without a change in specificity. The contribution of the infraspinatus to abduction strength is great. In the acute situation, the teres minor does not contribute more than 20% of external rotation strength at any degree of abduction.

Effect of experimental suprascapular nerve block on active glenohumeral translations in vivo.

Static superior shoulder instability is associated with long-standing rotator cuff tears. Factors or mechanisms which can prevent superior migration of the humeral head, and therefore allow preservation or restoration of shoulder function despite nonanatomical cuff repair, are poorly understood. The question has therefore arisen, whether centering of the humeral head was the result of active shoulder muscle function. It was the goal of this experimental investigation to (1) determine the pattern of glenohumeral translations during active shoulder abduction measured by open-magnetic resonance imaging (MRI) techniques, and to (2) determine the influence of experimental paralysis of the infra- and supraspinatus muscles on these translations. In contrast to prior experimental investigations, the humeral head remained always centered in the glenoid fossa during active abduction. No superior migration of the humeral head could be provoked with experimental paralysis of the supra- and/or infraspinatus muscles. The hypothesis that static or dynamic superior humeral head displacement is prevented by active-supra- and/or infraspinatus muscle function must therefore be rejected, for the shoulder with a structurally intact muscle-tendon-bone unit.

The feasibility and complications of the continuous popliteal nerve block: a 1001-case survey.

Perineural catheters are increasingly used worldwide for the treatment of postoperative pain in orthopedics. Long-term complications associated with the placement of a perineural catheter remain largely unstudied. We investigated the efficacy and the acute and late complications associated with the continuous popliteal nerve block. One-thousand-one patients undergoing elective surgery of the ankle or foot and scheduled to have a continuous popliteal nerve block were prospectively evaluated. All patients received an initial bolus of 40 mL ropivacaine 0.5% through the catheter. A continuous infusion of ropivacaine 0.3% initiated 6 h after the initial bolus was administered for the first 24 h and then decreased to ropivacaine 0.2% until the end of the study period. The success rate and acute complications were recorded. The overall success rate was 97.5%. The highest success rate was associated with foot inversion. Acute complications consisted of paresthesias during nerve localization (0.5%), pain during local anesthetic application (0.8%), and blood aspiration (0.4%). No central nervous system toxicity or cardiotoxicity occurred. Late complications were checked at 10 days and 3 mo after surgery. These included two cases of inflammation at the puncture site. No infection or neuropathy was observed. The use of continuous popliteal nerve block for ankle or foot surgery is associated with frequent success and few acute and late complications.

Extracorporeal Membrane Oxygenation for Treatment of Acute Inverted Takotsubo-Like Cardiomyopathy From Hemorrhagic Pheochromocytoma in Late Pregnancy.

We describe the first case of a pregnant woman presenting with an acute inverted takotsubo-like cardiomyopathy caused by a postpartum diagnosed hemorrhagic pheochromocytoma, successfully treated with percutaneous venoarterial extracorporeal membrane oxygenation (va-ECMO). During admission, an emergency cesarean delivery had to be performed. The fetus needed resuscitation for 5 minutes. The mother was successfully resuscitated and treated with percutaneous va-ECMO for 7 days. Despite advances in diagnostic techniques during the past decade, in many cases, pheochromocytoma in pregnancy is still missed. This results in a maternal and fetal mortality rate of up to 30% in both.

Interscalene brachial plexus anesthesia with ropivacaine 5 mg/mL and bupivacaine 5 mg/mL: effects on electrocardiogram.

BACKGROUND: Cardiotoxicity is the most severe complication of long-acting local anesthetics. The aim of this trial is to compare early signs of depression of cardiac conduction linked with the administration of either ropivacaine or bupivacaine for interscalene block. METHODS: Thirty-two patients (American Society of Anesthesiologists I/II) scheduled for elective shoulder arthroscopy were prospectively enrolled to receive, in a randomized and double-blind fashion, either 40 mL of ropivacaine 5 mg/mL or 40 mL of bupivacaine 5 mg/mL for interscalene block. Holter monitoring was started the night before surgery and continued until the end of the study. Peripheral blood sampling was performed before administration of local anesthetics (= baseline) and 15, 20, 25, 30, 35, 40, 45, 60, and 360 minutes after completion of the interscalene block for measurement of total and unbound concentration of the 2 local anesthetics. Alpha-1-acid-glycoprotein was measured at baseline, t(30), and t(360). RESULTS: All anesthetic blocks in both groups were successful and comparable. Electrocardiographic recordings for QRS, QT, and QTC intervals did not change and were similar in both groups. In the bupivacaine group, significant prolongation of the PQ interval was noted 15 minutes after drug application and remained significantly prolonged until t(60). Total and unbound plasma local-anesthetic concentrations were comparable between both groups at all times. In both groups, local-anesthetic plasma mean levels reached a peak between 30 and 45 minutes after the bolus application. The highest mean plasma levels were 0.103 (+/-0.05) mg/L for unbound ropivacaine and 0.084 (+/-0.03) mg/L for unbound bupivacaine, which occurred in both groups at t(30). CONCLUSIONS: Electrocardiographic recordings were similar in both groups, except for a significant prolongation of the PQ interval in the bupivacaine group at plasma levels below threshold for cardiotoxicity.

Clinical evaluation of a modified posterior anatomical approach to performing the popliteal block.

BACKGROUND: Tibial and common peroneal nerves can be blocked by the posterior approach to the popliteal fossa. Techniques using fixed measured distances between knee skin crease and puncture point have been described. We report on an approach that is based on manual identification of the apex of the popliteal fossa. METHODS: Five-hundred patients undergoing surgery of ankle or foot were prospectively included. The apex of the popliteal fossa (determined by the crossing point of the biceps femoris and the semitendinosus and semimembranosus muscles) was assessed by manual palpation. The puncture point was 0.5 cm below the apex, on the medial side of the biceps femoris muscle. When indicated for postoperative analgesia, a perineural catheter was placed. We assessed success rate, number of attempts, the distance between knee skin crease and the apex of the popliteal fossa, nerve depth, and acute and late complications. RESULTS: Block success rate was 94% and 92% when the block was performed through the needle and the catheter, respectively. Inversion was the motor response with the highest success rate. The first attempt was successful in 97.5% of the patients. Mean depth of the nerve was 4.5 cm (range, 2.0 to 7.0 cm) and mean knee skin crease to apex of popliteal fossa distance was 9 cm (range, 7.0 to 12.0 cm). Nine patients (2%) had acute complications. There were no technical problems associated with the perineural nerve catheter. After 12 weeks, no late complications were observed. CONCLUSIONS: The modified posterior anatomical approach for popliteal sciatic nerve block is easy to perform, has a high success rate, and has a low complication rate. The location of the needle insertion point is assessed without any measurement, thus avoiding inaccuracies caused by repeated skin-distance measurements.

Diaphragmatic excursion and respiratory function after the modified Raj technique of the infraclavicular plexus block.

BACKGROUND: The effects of the infraclavicular plexus block using the modified Raj approach on diaphragm and respiratory function have not been investigated. METHODS: After obtaining approval of the local ethics committee and written informed consent, 20 patients, scheduled for surgery of the forearm, wrist, or hand were prospectively included. Infraclavicular block was performed using the modified Raj technique with 40 to 50 mL ropivacaine 0.5%. Forced diaphragmatic excursion (DE), vital capacity (VC), first-second forced expiratory volume (FEV(1)), and peak expiratory flow rate (PEFR) were assessed the day before surgery and 30 and 360 minutes after blocks, respectively. RESULTS: There was no significant difference between pre- and postblock values, neither for DE (5.6 +/- 1.0 cm before the block, 5.2 +/- 1.4 cm 30 minutes after the block, and 5.7 +/- 1.4 cm 360 minutes after the block) nor for VC (3.2 +/- 0.8 L before the block, 3.1 +/- 0.9 L 30 minutes after the block, and 3.0 +/- 0.9 L 360 minutes after the block), FEV(1) (2.8 +/- 0.9 L before the block, 2.8 +/- 0.9 L 30 minutes after the block, and 2.7 +/- 0.9 L 360 minutes after the block), or PEFR (378 +/- 116 L/min before the block, 355 +/- 110 L/min 30 minutes after the block, and 364 +/- 116 L/min 360 minutes after the block). CONCLUSION: Infraclavicular block using the modified Raj technique did not interfere with diaphragmatic excursion or respiratory function.

The length of stay in the post-anaesthesia care unit correlates with pain intensity, nausea and vomiting on arrival.

BACKGROUND: The benefit of the post-anaesthesia care unit (PACU) with respect to an early detection of postoperative complications is beyond dispute. From a patient perspective, prevention and optimal management of pain, nausea and vomiting (PONV) are also of utmost importance. The aims of the study were therefore to prospectively measure pain and PONV on arrival to the PACU and before discharge and to determine the relationship of pain and PONV to the length of stay in the PACU. METHODS: Postoperative pain was assessed over 30 months using a numeric rating scale on admittance to the PACU and before discharge; in addition, PONV was recorded. Statistical analysis was done considering gender, age, American Society of Anesthesiologists (ASA) classification, surgical speciality, anaesthesia technique, duration of anaesthesia, intensity of nursing and length of stay. RESULTS: Data of 12,179 patients were available for analysis. The average length of stay in the PACU was 5.7 ± 5.9 h, whereas regular PACU patients stayed for 3.2 ± 1.9 h and more complex IMC patients stayed for 15.1 ± 6.0 h. On admittance, 27% of patients were in pain and the number decreased to 13% before discharge; 3% experienced PONV. Risk factors for increased pain determined by multivariate analysis were female gender; higher ASA classification; general, cardiac and orthopaedic surgery and prolonged case duration. In more complex IMC patients, pain scores were higher on arrival but dropped to similar levels before discharge compared to regular PACU patients. Female gender and postoperative pain were risk factors for postoperative vomiting. Pain and PONV on arrival correlated with length of stay in the PACU. Pain- or PONV-free patients stayed almost half of the time in the PACU compared to patients with severe pain or vomiting on arrival. CONCLUSIONS: The majority of PACU patients had good pain control, both on admittance and before discharge, and the overall incidence of PONV was low. Managing patients in the PACU could achieve a significant reduction of pain and PONV. The level of pain and presence of PONV on admittance to the PACU correlate with and act as predictors for increased length of PACU stay.

Elevated CSF histamine levels in multiple sclerosis patients.

BACKGROUND: Histamine is an ubiquitous inflammatory mediator of numerous physiological processes. Histamine and its receptors have been implicated in multiple sclerosis (MS) disease pathogenesis. We prospectively enrolled 36 MS patients and 19 age and gender-matched healthy volunteers for cerebrospinal fluid (CSF) histamine analysis. FINDINGS: CSF HISTAMINE LEVELS IN MS PATIENT SAMPLES WERE SIGNIFICANTLY HIGHER (MEDIAN: 35.6 pg/ml) than in controls (median: 5.5 pg/ml; Beta = 0.525, p < 0.001). In addition, histamine increased with age (Pearson's correlation, p < 0.003). CONCLUSIONS: Histamine may be an important factor for both the initiation and maintenance of chronic inflammatory diseases of the central nervous system. Our observation encourages a deeper investigation of the role of histamine in MS.