A prospective randomized double-blind trial of the efficacy of a bilateral lumbar erector spinae block on the 24h morphine consumption after posterior lumbar inter-body fusion surgery.

BACKGROUND: Spine surgery is associated with considerable postoperative pain and can be challenging to treat. A loco-regional technique suitable for spine surgery should cover the dorsal root of the spinal nerves at the levels where surgery is performed. The erector spinae block is a loco-regional technique with promising results and was recently described at the thoracic level. There are no randomized trials of this technique on a lumbar level. This study tests the hypothesis that the 24-h postoperative morphine consumption is significantly lower in patients undergoing posterior lumbar inter-body fusion surgery with a lumbar erector spinae (LUMBES) block when compared with a sham block. METHODS: This prospective randomized double-blind multicenter study will randomly allocate 80 adult patients undergoing elective posterior lumbar inter-body fusion surgery during general anesthesia to one of two groups as follows: (1) bilateral erector spinae block (20 mL 0.25% levobupivacaine) or (2) bilateral sham block (20 mL NaCl 0.9%). Our primary endpoint is 24-h postoperative morphine consumption. Secondary endpoints include 72-h morphine consumption, intraoperative sufentanil dosage, postoperative pain scores at regular time intervals both at rest and during movement, time to first postoperative mobilization, and the Quality of Recovery 40 survey score. DISCUSSION: The LUMBES trial is a pragmatic clinical study that will provide evidence of whether a bilateral lumbar erector spinae block is effective in reducing 24-h postoperative morphine consumption in patients undergoing lumbar inter-body fusion surgery. If this hypothesis is confirmed, this finding could contribute to more widespread implementation of this technique. TRIAL REGISTRATION: Local ethics committee B300201837508, ClinicalTrials.gov identifier: NCT03825198 . Registered on 31 Jan 2019.

Ultrasound-guided approach to nerves (direct vs. tangential) and the incidence of intraneural injection: a cadaveric study.

This study evaluated the incidence of nerve puncture and intraneural injection based on the needle approach to the nerve (direct vs. tangential). Two expert operators in regional anaesthesia performed in-plane ultrasound-guided nerve blocks (n = 158) at different levels of the brachial plexus in cadavers, aiming either directly for the nerve (n = 77) or tangentially inferior to the nerve (n = 81). After reaching the outer limit of the nerve, the needle was intentionally advanced approximately 1 mm in both approaches, and 0.2-0.5 ml of saline was injected. Each operator classified (in real time) the needle tip and injectate as intraneural or not. Video clips showing the final position of the needle and the injection were evaluated in the same manner by seven independent expert observers who were blinded to the aims of this study. In addition, 20 injections were performed with ink for histological evaluation. Intraneural injections of saline were observed by the operator in 58% (45/77) of cases using the direct approach and 12% (10/81) of cases using the tangential approach (p < 0.001). The independent observers agreed with the operator in a substantial number of cases (Cohen's kappa index 0.65). Histological studies showed intraneural spread in 83% (5/6) of cases using the direct approach and in 14% (2/14) of cases using the tangential approach (p = 0.007). No intrafascicular injections were observed. There was good agreement between the operators' assessment and subsequent histological evaluation (Cohen's kappa = 0.89). Simulation of an unintentional/accidental advancement of the needle 'beyond the edge' of the nerve suggests significantly increased risk of epineural perforation and intraneural injection when a direct approach to the nerve is used, compared with a tangential approach.

Postsurgical compartment syndrome of the forearm diagnosed in a child receiving a continuous infra-clavicular peripheral nerve block.

Opinions diverge as to whether or not regional anaesthesia delays the diagnosis of evolving acute compartment syndrome. Withholding regional anaesthesia from patients with painful orthopaedic injuries may be ethically unacceptable, however. In this report, we describe a case of acute compartment syndrome in a 4-year old child who underwent resection of a forearm osteochondroma. Analgesia was satisfactory during the first post-operative night, but the child later complained of pain despite an effective infra-clavicular block. Motor function and sensibility were disturbed and the fingers were swollen. The forearm cast was removed as it was suspected to be causing external compression. Pain disappeared while motor function and sensation recovered. The child was discharged without any complications. Despite an effective peripheral nerve block and the young age of the patient, the diagnosis of acute compartment syndrome could be made thanks to a well-defined post-operative analgesia protocol, a high level of suspicion and careful clinical assessment when break-through pain occurred.

Intrathecal chloroprocaine vs. lidocaine in day-case surgery: recovery, discharge and effect of pre-hydration on micturition.

BACKGROUND: This randomised, double blind prospective study compares intrathecal lidocaine with chloroprocaine in day-case surgery and the influence of a 500 ml pre-load intravenously. We tested the hypothesis that chloroprocaine provides faster recovery and discharge in day-case surgery. Secondary we studied the influence of a preload compared with fluid restriction on discharge time and micturition problems. METHODS: One hundred patients undergoing day-case arthroscopy were randomised to receive either lidocaine (L) 60 mg or chloroprocaine (CP) 40 mg intrathecally and this with (L+, CP+) or without (L−, CP−) a 500 ml pre-load of crystalloid. Block characteristics, micturition and discharge times were registered. Bladder volumes were monitored by ultrasound. Micturition problems received a micturition score. RESULTS: Onset and quality of the block were comparable between groups. Time to regain Bromage 1 and L2 regression were shorter for the CP group compared with the L group. Voiding (168 ± 44 min) and discharge (178 ± 52 min) were approximately 40 min faster for the CP group compared with the L group. Pre-load provided faster bladder filling but there were no differences in voiding time within the CP or L group. The CP+ group (166 ± 36 min) was discharged faster than both L groups (226 ± 57 min, 227 ± 59 min). More serious micturition problems occurred in the L+ group compared with both CP groups. CONCLUSION: Chloroprocaine is suitable for day-case surgery because of faster block regression and discharge than lidocaine. A 500 ml pre-load may not affect discharge but did not increase micturition problems for chloroprocaine.

Clinical guidelines for the practice of peripheral nerve blocks in the adult.

These guidelines, made by BARA, are, like the "Safety First Guidelines" of the SARB, clinical recomendations for a good and safe practice when performing peripheral nerve blocks (PNB). These recommendations were made according to the most recent literature and experts opinion and are therefore prone to changes due to evolution of literature. The guidelines deal with "Informed Consent", preoperative visit, monitoring, equipment and the PNB procedure itself regardless of using ultrasound or neurostimultion or both. Advise is given when combining a PNB with general anesthesia and when a catheter technique is used.

Supraclavicular brachial plexus blocks: review and current practice.

This article reviews the possible revival of the supraclavicular brachial plexus blockade due to the use of ultrasound guidance. The brachial plexus is a complex network of nerves, extending from the neck to the axilla, which supplies motor and sensory fibers to the upper extremity. Understanding the complexities of the formation and structure of the brachial plexus remains a cornerstone for effective regional anaesthesia. On the level of the supraclavicular fossa, the plexus is most compactly arranged. The supraclavicular approach of the brachial plexus has a high success rate including blockade of the ulnar and musculocutaneous nerve, which can be missed respectively with the interscalene and axillary approach. However, because of the proximity of the pleura, most anaesthesiologists have been reluctant to perform this supraclavicular approach. The introduction of ultrasound guidance techniques not only reduces the possible risk of pneumothorax but also allows a faster onset time of the block with a reduction of the local anaesthetic dose. This makes the supraclavicular approach a valuable alternative to the axillary, interscalene and infraclavicular approach for upper limb surgery.

The effects of beta-adrenergic stimulation on the length-dependent regulation of myocardial function in coronary surgery patients.

UNLABELLED: Increasing cardiac load by leg elevation identifies patients with load-dependent impairment of left ventricular (LV) function. This impairment is related to a deficient length-dependent regulation of LV function. We investigated the effects of dobutamine on length-dependent regulation of LV function in coronary surgery patients (n = 25). High-fidelity LV pressure tracings were obtained at end-expiration, while hearts were paced at a fixed rate of 90 bpm. Effects of leg elevation on contraction and relaxation were compared before and during dobutamine 5 microg x kg(-1) x min(-1). Effects on contraction were evaluated by analysis of changes in dP/dtmax. Effects on relaxation were assessed by analysis of R (slope of the relation between the time constant of isovolumic relaxation and end-systolic pressure). Correlations were calculated with linear regression analysis using Pearson's coefficient r. The effects of leg elevation on variables of contraction and relaxation were coupled. We found a close relationship between changes in dP/dtmax and individual values of R (r = 0.84; P < 0.001). Dobutamine improved myocardial function and accelerated LV pressure decrease. Under dobutamine, the increase in dP/dtmax with leg elevation was larger (P < 0.001) and load dependence of LV relaxation was reduced (P = 0.001). Dobutamine improved the effects of leg elevation on LV function, reflecting improved length-dependent regulation of LV function. IMPLICATIONS: This study demonstrated that beta-adrenoreceptor stimulation with dobutamine improved length-dependent regulation of myocardial function assessed during leg elevation in cardiac surgical patients.

Seven-year review of requests for epidural blood patches for headache after dural puncture: referral patterns and the effectiveness of blood patches.

A review was undertaken of all 190 patients who were referred over 7 years, from 1991 to 1997 inclusive, for an epidural blood patch as a treatment for headache after dural puncture. The patterns of referral and symptoms, the distributions of age and gender and the effectiveness of the blood patch were examined. Most of the referrals (n = 153) were after deliberate diagnostic dural puncture in neurology and neuroradiology, with a minority (n = 28) used for anaesthesia and obstetrics, which were mostly inadvertent. Another nine cases were related to placement of an intrathecal catheter. The numbers of referrals per year reached a maximum in 1995 before falling again, a curious inverse relation to the number of invasive neuro-radiological diagnostic procedures. Most of the patients were between 30 and 50-years-old, with 25 younger than 30 and 14 older than 60. Women accounted for 70% of the referrals for headache, although the gender ratio amongst patients subjected to at risk procedures appeared closer to 50:50. Neckache accompanied the headache in 85% of cases, auditory problems were volunteered by three patients and one patient had diplopia for 6 weeks. Of the 190 patients who were referred, 186 received at least one patch, the symptoms in the remaining four being too mild or atypical to warrant blood patch treatment. This provided initial relief in all but two patients, one of whom received a further epidural blood patch with no effect. There was sustained relief of symptoms in 136 and a partial relapse in 38 patients, which resolved without needing any further blood patch. A second patch was provided for seven patients and a third for three patients, of whom two were cured. Of the patients who needed more than one blood patch, nine were after inadvertent dural puncture with a Tuohy needle and, of these patients, six were in labour. A total of 200 patches were provided in all for the 186 patients and all but three patients had a satisfactory outcome. Epidural blood patches are effective in treating headache after dural puncture, but less successful than is commonly believed, especially after inadvertent dural taps. A relapse after treatment does not always require a second patch. Specialities other than anaesthesia seemed reluctant to accept the benefits in both cost and comfort of using needles of improved design for dural puncture.

Effects of nicardipine and urapidil on length-dependent regulation of myocardial function in coronary artery surgery patients.

OBJECTIVE: To assess effects of a decrease in left ventricular (LV) afterload (pharmacologically induced by nicardipine and urapidil) on myocardial contraction and relaxation, with emphasis on the effects on load dependence of myocardial function. DESIGN: Prospective, blinded study. SETTING: University hospital. PARTICIPANTS: Coronary artery surgery patients. INTERVENTIONS: Alterations of systolic load were effected by leg elevation in control conditions and after administration of either nicardipine or urapidil before and after cardiopulmonary bypass. MEASUREMENTS AND MAIN RESULTS: High-fidelity LV pressure tracings were obtained at end-expiration while hearts were paced at a fixed rate of 90 beats/min. Hemodynamic effects of leg elevation were compared before and after nicardipine, 7 microg/kg (n = 15), and before and after urapidil, 0.4 mg/kg (n = 15). The effects of leg elevation on parameters of contraction and relaxation were coupled. Both nicardipine and urapidil similarly decreased systolic pressures and peripheral resistance. Nicardipine decreased rate of pressure development (dP/dtmax) and slowed LV pressure fall, whereas load dependence of LV relaxation was not altered. Urapidil did not alter dP/dtmax, rate of LV pressure fall, or load dependence of relaxation. Similar results were observed after cardiopulmonary bypass. CONCLUSIONS: The results of the present study indicate that a pharmacologically induced moderate reduction in LV afterload with nicardipine or urapidil did not alter the length-dependent regulation of myocardial function.

[Quality of induction and adrenocortical function. A clinical comparison of Etomidate-Lipuro and Hypnomidate]. / Induktionsqualität und Nebennierenrindenfunktion. Ein klinischer Vergleich von Etomidat-Lipuro und Hypnomidate.

UNLABELLED: The purpose of this study was to compare etomidate in a lipid emulsion (Etomidat-Lipuro; Braun, Melsungen) and in propylene glycol (Hypnomidate, Janssen Pharmaceutica) in 90 patients in terms of anaesthetic induction characteristics with special reference to injection side effects, haemodynamic changes, and quality of induction. Adrenocortical hormones were determined in 30 patients who received either Etomidat-Lipuro, Hypnomidate, or propofol (Diprivan, ICI Pharma) for induction of anaesthesia. METHODS: One hundred twenty patients gave their informed consent to the study. In the first part, 90 patients were assigned at random to two groups in which induction of anaesthesia was performed either with Etomidat-Lipuro or Hypnomidate. Anaesthesia was started by i.v. injection of 25 micrograms/kg alfentanil (Rapifen, Janssen Pharmaceutica). One minute later, the hypnotic agent was injected into a freely running i.v. line (18 Gcannula) that was used only for the hypnotic and was removed 15 min later. During injection, the patients were asked to inform the anaesthesiologist spontaneously and on request about their sensations at the injection site. The time from the beginning of anaesthesia until the disappearance of the eyelash reflex was measured. The patients were ventilated and vecuronium was administered to allow good intubation conditions 2-3 min later. For the first 10 min, blood pressure and heart rate were measured every minute. Postoperatively, the same investigator made rounds once a day and examined the injection sites. Signs of pain, redness, swelling, induration, thrombophlebitis, or thrombosis were noted. In the second part of the study, 30 patients were investigated for endocrinological changes after induction of anaesthesia with Etomidat-Lipuro, Hypnomidate, or Diprivan. The patients were allocated to the groups at random. A radial artery catheter was inserted in every patient. Sampling took place 30 min before and 1 and 2 h after induction. Additional samples were drawn 30 min and 1, 2, and 22 h after i.v. administration of 0.25 mg ACTH (Synacthen, Ciba-Geigy). The plasma concentrations of cortisol, 17 alpha-OH-progesterone, and aldosterone and the renin activity were determined by high-performance liquid chromatography. RESULTS: The loss of the eyelash reflex occurred 42.9 +/- 8.7 and 42.2 +/- 11.0 s after the administration of Etomidat-Lipuro and Hypnomidate. The haemodynamic changes were minimal in both groups. After administration of alfentanil, local side effects of the hypnotics were scarce, with a tendency to be weaker and more seldom after Etomidat-Lipuro (3/55 versus 8/55). The postoperative vein reactions were generally mild and occurred in 17 out of 55 patients after Etomidat-Lipuro and 15 out of 55 patients after Hypnomidate. In most cases these signs were no longer present on the 2nd day after the procedure. Cortisol levels were depressed initially by all the hypnotic drugs used. While there was spontaneous recovery in the Diprivan group after 2 h combined with a positive overshooting response to ACTH stimulation, in the etomidate groups cortisol could not be stimulated; it normalized slowly during the following 24 h. The 17 alpha-OH-progesterone increase was significant in the etomidate groups after the administration of ACTH. The aldosterone levels decreased after etomidate injection and had not normalized 24 h later, while there was a normal response to ACTH in the propofol group. There was a normal decrease in renin activity in all three groups after the administration of ACTH. CONCLUSION: Local side effects are minimal after the administration of Etomidat-Lipuro and Hypnomidate. Alfentanil reduces the injection pain of etomidate induction agents. Cortisol and aldosterone are depressed by etomidate, but the clinical relevance is minimal after a single bolus injection.

Pulmonary embolism confirmed by transoesophageal echocardiography.

A 60-year-old patient suffered a pulmonary embolism following the application of an Esmarch and pneumatic tourniquet before arthroscopy of the knee. The diagnosis was suspected because of sudden hypotension, ECG changes, a decrease in end-expiratory carbon dioxide concentration and oxygen desaturation as indicated by pulse oximetry. Before performing a sternotomy and cardiopulmonary bypass for removal of pulmonary artery clots, the diagnosis was confirmed by the demonstration of severe right ventricular strain using transoesophageal echocardiography.