Transmuscular Quadratus Lumborum Block versus Infrainguinal Fascia Iliaca Nerve Block for Patients Undergoing Elective Hip Replacement: A Double-blinded, Pilot, Randomized Controlled Trial.

Purpose: Transmuscular quadratus lumborum (TQL) block has been described as an effective option for postoperative analgesia in patients undergoing hip replacement with single injection described as providing analgesia for up to 24 h. We hypothesize that a TQL block, when compared to fascia iliaca block (FIB), will provide better analgesia and less motor block in the initial 24-h postoperative period. Patients and Methods: Fifty patients undergoing elective hip replacement surgery, ASA I-III, were included in the study. Patients were randomized into two groups. Patients in group A received spinal anesthesia followed by FIB. Patients in group B received spinal anesthesia followed by TQLB. Postoperative pain scores and motor block were assessed at 6 and 24 hours. The primary outcome measure was 24 h total morphine consumption. Secondary outcome measures included pain score (VNS) and motor block (modified Bromage scale) at 6 and 24 h postoperatively. Results: There was no statistical difference in morphine consumption between the two groups (p-value 0.699). There was no difference in pain scores at 6 h (p-value 0.540) or 24 h (p-value 0.383). There was no difference in motor block at 6 h (p-value 0.497) or at 24 h (p-value 0.773). Conclusion: Transmuscular quadratus lumborum block along with spinal anesthesia for patients undergoing elective hip replacement surgery does not reduce opioid consumption or motor weakness when compared to fascia iliaca block. The results and conclusion apply to a dose of 20 mL of 0.25% bupivacaine used in each group.

Can saline injection protect phrenic nerve? - A randomised controlled study.

BACKGROUND AND AIMS: Various methods were attempted to reduce the incidence of phrenic nerve palsy during interscalene brachial plexus nerve block. Mechanism of phrenic palsy was presumed to be due to the spread of local anaesthetic anterior to the anterior scalene muscle. We hypothesised that by injecting saline in this anatomical location prior to performing an interscalene block might reduce the incidence of phrenic palsy. METHODS: This was a double-blinded randomised controlled study performed in a single-centre, university-teaching hospital. A total of 36 patients were randomised to either group C (conventional group) or group S (saline group). Ultrasound-guided interscalene block was administered with 20 ml of 0.25% levo-bupivacaine in both groups. Ten ml of normal saline was injected anterior to anterior scalene muscle in group S prior to performing interscalene block. A blinded radiologist performed diaphragmatic ultrasound pre- and post-operatively to document phrenic palsy. Bedside spirometry was used to perform baseline and post-operative pulmonary function test. The primary outcome was to look at the incidence of phrenic palsy as measured by diaphragmatic palsy on ultrasound performed by radiologist. Statistical Package for the Social Sciences (SPSS) version 25 was used for statistical analysis. RESULTS: Significantly less patients in the saline group developed diaphragmatic paresis when compared to conventional group (44% vs. 94%, Chi-squared = 10.01, P = 0.002). There was no difference in post-operative pain, subjective sensation of dyspnoea or patient satisfaction between the groups. CONCLUSION: Injecting saline anterior to anterior scalene muscle reduces the incidence of diaphragmatic palsy when performing interscalene block.

Comment on: "A structured pathway for accelerated postoperative recovery reduces hospital stay and cost of care following microvascular breast reconstruction without increased complications".

We read with great interest a recent article by O'Neill et al. on the implementation of an accelerated postoperative recovery protocol following DIEP flap breast reconstruction. Our department has formally introduced a DIEP Enhanced Recovery After Surgery (ERAS) Pathway in May 2019. Although in a much smaller sample size, our results were similar to this article and we would agree with the authors' conclusion that implementation of such protocol could effectively reduce the length of inpatient stay (LoS) and cost of care, without compromising patient care nor increasing complication rates. Prior to the introduction of ERAS Pathway, 28 of our patients who had DIEP between November 2018 and May 2019 had an mean LoS of 7.1 days (median 6 days, range 5-21 days); whereas 27 patients who experienced the ERAS Pathway between May and December 2019 had an mean LoS of 4.8 days (median 5 days, range 3-7 days). The cost of inpatient stay in a normal ward at our hospital is approximately £232 per patient per day. By reducing an extra 2.3 days of inpatient stay, our Trust could save at least an average of £32,016 per annum with the estimated 60 DIEP performed annually at our department. We would like to emphasise the benefits and effectiveness of this multimodal, patient-centre and evidence-based ERAS. This, perhaps, should be the standard of care for all patients who undergo microvascular breast reconstruction in the future.

Facet joint degeneration adversely affects ultrasound imaging of the lumbar spine.

AIM: Ultrasound of neuraxis can be used to identify the best possible inter-spinous space to perform neuraxial block. The aim of this study was to assess the anatomical correlation between neuraxial ultrasound and magnetic resonance imaging (MRI). MATERIAL AND METHOD: Twenty-one patients who underwent MRI of the lumbar spine had ultrasound of lumbar neuraxis performed by an experienced operator. Each lumbar interspinous space was graded on ultrasound as good [posteriorcomplex (ligamentum flavum and duramater) and anterior complex (posterior longitudinal ligament) visible], intermediate (either anterior complex or posterior complex visible) or poor (both anterior complex and posterior complex not visible) in both the transverse median (TM) and paramedian sagittal oblique (PSO) plane. Pre-determined MRI parameters were measured by a radiologist blinded to sonographic findings at each inter-spinal level. RESULTS: Seventy-eight lumbar interspinous spaces were evaluated. There was a significant association (p<0.004) between the facet joint degeneration on MRI and the poor ultrasound view in the transverse median (TM) group. The odds of obtaining a poor view in TM plane was 7 times higher (95% CI 1.7-28.9, p=0.007) in the presence of facet joint degeneration. None of the other variables had a significant association with a poor neuraxial view in the TM plane. Poor views in the parasagittal oblique (PSO) plane did not correlate with any of the variables measured on MRI. CONCLUSION: Facet joint degeneration is a major contributing factor to poor neuraxial ultrasound views in the TM plane.

Proficiency-based progression training: an 'end to end' model for decreasing error applied to achievement of effective epidural analgesia during labour: a randomised control study.

BACKGROUND: Training procedural skills using proficiency-based progression (PBP) methodology has consistently resulted in error reduction. We hypothesised that implementation of metric-based PBP training and a valid assessment tool would decrease the failure rate of epidural analgesia during labour when compared to standard simulation-based training. METHODS: Detailed, procedure-specific metrics for labour epidural catheter placement were developed based on carefully elicited expert input. Proficiency was defined using criteria derived from clinical performance of experienced practitioners. A PBP curriculum was developed to train medical personnel on these specific metrics and to eliminate errors in a simulation environment.Seventeen novice anaesthetic trainees were randomly allocated to undergo PBP training (Group P) or simulation only training (Group S). Following training, data from the first 10 labour epidurals performed by each participant were recorded. The primary outcome measure was epidural failure rate. RESULTS: A total of 74 metrics were developed and validated. The inter-rater reliability (IRR) of the derived assessment tool was 0.88. Of 17 trainees recruited, eight were randomly allocated to group S and six to group P (three trainees did not complete the study). Data from 140 clinical procedures were collected. The incidence of epidural failure was reduced by 54% with PBP training (28.7% in Group S vs 13.3% in Group P, absolute risk reduction 15.4% with 95% CI 2% to 28.8%, p=0.04). CONCLUSION: Procedure-specific metrics developed for labour epidural catheter placement discriminated the performance of experts and novices with an IRR of 0.88. Proficiency-based progression training resulted in a lower incidence of epidural failure compared to simulation only training. TRIAL REGISTRATION NUMBER: NCT02179879. NCT02185079; Post-results.

Pre-procedure ultrasound-guided paramedian spinal anaesthesia at L5-S1: Is this better than landmark-guided midline approach? A randomised controlled trial.

BACKGROUND AND AIMS: Routine use of pre-procedural ultrasound guided midline approach has not shown to improve success rate in administering subarachnoid block. The study hypothesis was that the routine use of pre-procedural (not real time) ultrasound-guided paramedian spinals at L5-S1 interspace could reduce the number of passes (i.e., withdrawal and redirection of spinal needle without exiting the skin) required to enter the subarachnoid space when compared to the conventional landmark-guided midline approach. METHODS: After local ethics approval, 120 consenting patients scheduled for elective total joint replacements (Hip and Knee) were randomised into either Group C where conventional midline approach with palpated landmarks was used or Group P where pre-procedural ultrasound was used to perform subarachnoid block by paramedian approach at L5-S1 interspace (real time ultrasound guidance was not used). RESULTS: There was no difference in primary outcome (difference in number of passes) between the two groups. Similarly there was no difference in the number of attempts (i.e., the number of times the spinal needle was withdrawn from the skin and reinserted). The first pass success rates (1 attempt and 1 pass) was significantly greater in Group C compared to Group P [43% vs. 22%, P = 0.02]. CONCLUSION: Routine use of paramedian spinal anaesthesia at L5-S1 interspace, guided by pre-procedure ultrasound, in patients undergoing lower limb joint arthroplasties did not reduce the number of passes or attempts needed to achieve successful dural puncture.

Surface dose measurements and comparison of unflattened and flattened photon beams.

The purpose of this study was to evaluate the central axis dose in the build-up region and the surface dose of a 6 MV and 10 MV flattened photon beam (FB) and flattening filter free (FFF) therapeutic photon beam for different square field sizes (FSs) for a Varian Truebeam linear accelerator using parallel-plate ionization chamber and Gafchromic film. Knowledge of dosimetric characteristics in the build-up region and surface dose of the FFF is essential for clinical care. The dose measurements were also obtained empirically using two different commonly used dosimeters: a p-type photon semiconductor dosimeter and a cylindrical ionization chamber. Surface dose increased linearly with FS for both FB and FFF photon beams. The surface dose values of FFF were higher than the FB FSs. The measured surface dose clearly increases with increasing FS. The FFF beams have a modestly higher surface dose in the build-up region than the FB. The dependence of source to skin distance (SSD) is less significant in FFF beams when compared to the flattened beams at extended SSDs.

Conventional Landmark-Guided Midline Versus Preprocedure Ultrasound-Guided Paramedian Techniques in Spinal Anesthesia.

BACKGROUND: Multiple passes and attempts while administering spinal anesthesia are associated with a greater incidence of postdural puncture headache, paraesthesia, and spinal hematoma. We hypothesized that the routine use of a preprocedural ultrasound-guided paramedian technique for spinal anesthesia would reduce the number of passes required to achieve entry into the subarachnoid space when compared with the conventional landmark-guided midline approach. METHODS: One hundred consenting patients scheduled for elective total joint replacements (hip and knee) were randomized into group C (conventional) and group P (preprocedural ultrasound-guided paramedian technique) with 50 in each group. The patients were blinded to the study group. All spinal anesthetics were administered by a consultant anesthesiologist. In group C, spinal anesthetic was done via the midline approach using clinically palpated landmarks. In group P, a preprocedural ultrasound scan was used to mark the paramedian insertion site, and spinal anesthetic was performed via the paramedian approach. RESULTS: The average number of passes (defined as the number of forward advancements of the spinal needle in a given interspinous space, i.e., withdrawal and redirection of spinal needle without exiting the skin) in group P was approximately 0.34 times that in group C, a difference that was statistically significant (P = 0.01). Similarly, the average number of attempts (defined as the number of times the spinal needle was withdrawn from the skin and reinserted) in group P was approximately 0.25 times that of group C (P = 0.0021). In group P, on an average, it took 81.5 (99% confidence interval, 68.4-97 seconds) seconds longer to identify the landmarks than in group C (P = 0.0002). All other parameters, including grading of palpated landmarks, time taken for spinal anesthetic injection, periprocedural pain scores, periprocedural patient discomfort visual analog scale score, conversion to general anesthetic, paresthesia, and radicular pain during needle insertion, were similar between the 2 groups. CONCLUSIONS: Routine use of paramedian spinal anesthesia in the orthopedic patient population undergoing joint replacement surgery, guided by preprocedure ultrasound examination, significantly decreases the number of passes and attempts needed to enter the subarachnoid space.

Ultrasound for neuraxial blockade.

Neuraxial blockade is still largely performed as a blind procedure. Despite of developments in the type of needles used and drugs administered, the process of locating the epidural or intra-thecal space is still limited to identification of landmarks by palpation and reliance on tactile feedback of the operator. Ultrasound has provided the long needed "eye" to the procedure and has already shown promise of improving the safety and efficacy or neuraxial blocks. This review focuses on understanding the sonoanatomy of the neuraxial space, performing a systematic pre-procedural ultrasound scan, and reviewing the available evidence.

Ultrasound guided axillary brachial plexus block.

The axillary brachial plexus block is the most widely performed upper limb block. It is relatively simple to perform and one of the safest approaches to brachial plexus block. With the advent of ultrasound technology, there is a marked improvement in the success rate of the axillary block. This review will focus on the technique of ultrasound guided axillary brachial plexus block.

Objective improvement in upper limb lymphoedema following ipsilateral latissimus dorsi pedicled flap breast reconstruction--a case series and review of literature.

OBJECTIVE: We present a series of three patients whose upper limb lymphoedema (following total oncologic mastectomy and level III axillary clearance) resolved significantly after ipsilateral pedicled latissimus dorsi (LD) flap breast reconstruction. METHODS: A retrospective review of the medical records of patients who had undergone oncologic mastectomy and level III axillary clearance with subsequent LD pedicled flap reconstruction was carried out. Individuals who had undergone review and treatment by the lymphoedema service were identified and patients with incomplete pre- or post-operative records were excluded. A minimum follow-up period of 2 years of conservative therapy, as well as 2 years post-operatively was undertaken. RESULTS: The rate of improvement of lymphoedema following conservative therapy was, on average, 0.095 mL/week and reached a plateau at 2-year follow-up. Following latissimus dorsi flap breast reconstruction, the rate of improvement in lymphoedema increased in all three cases, with an average improvement of 2.55 mL/week and remained sustained in the follow-up period. CONCLUSION: Pedicled myocutaneous flap reconstruction of the ipsilateral breast proved to be a useful treatment for upper limb lymphoedema in our series. This adds an important dimension to the assessment and treatment of patients with upper limb oedema resulting from mastectomy and axillary clearance.

Characterization of proton production and consumption associated with microbial metabolism.

BACKGROUND: Production or consumption of protons in growth medium during microbial metabolism plays an important role in determining the pH of the environment. Such pH changes resulting from microbial metabolism may influence the geochemical speciation of many elements in subsurface environments. Protons produced or consumed during microbial growth were measured by determining the amount of acid or base added in a 5 L batch bioreactor equipped with pH control for different species including Escherichia coli, Geobacter sulfurreducens, and Geobacter metallireducens. RESULTS: An in silico model was used to predict the proton secretion or consumption rates and the results were compared with the data. The data was found to confirm predictions of proton consumption during aerobic growth of E. coli with acetate as the carbon source. However, in contrast to proton consumption observed during aerobic growth of E. coli with acetate, proton secretion was observed during growth of Geobacter species with acetate as the donor and Fe(III) as the extracellular electron acceptor. CONCLUSIONS: In this study, we have also shown that the final pH of the medium can be either acidic or basic depending on the choice of the electron acceptor for the same electron donor. In all cases, the in silico model could predict qualitatively the proton production/consumption rates obtained from the experimental data. Therefore, measurements of pH equivalents generated or consumed during growth can help characterize the microbial physiology further and can be valuable for optimizing practical applications such as microbial fuel cells, where growth associated pH changes can limit current generation rates.