Smart Optical Catheters for Epidurals.

Placing the needle inside the epidural space for locoregional anesthesia is a challenging procedure, which even today is left to the expertise of the operator. Recently, we have demonstrated that the use of optically sensorized needles significantly improves the effectiveness of this procedure. Here, we propose an optimized configuration, where the optical fiber strain sensor is directly integrated inside the epidural catheter. The new design allows the solving of the biocompatibility issues and increases the versatility of the former configuration. Through an in vivo study carried out on a porcine model, we confirm the reliability of our approach, which also opens the way to catheter monitoring during insertion inside biological spaces.

Low-dose buprenorphine infusion to prevent postoperative hyperalgesia in patients undergoing major lung surgery and remifentanil infusion: a double-blind, randomized, active-controlled trial.

BACKGROUND: Postoperative secondary hyperalgesia arises from central sensitization due to pain pathways facilitation and/or acute opioid exposure. The latter is also known as opioid-induced hyperalgesia (OIH). Remifentanil, a potent µ-opioid agonist, reportedly induces postoperative hyperalgesia and increases postoperative pain scores and opioid consumption. The pathophysiology underlying secondary hyperalgesia involves N-methyl-D-aspartate (NMDA)-mediated pain pathways. In this study, we investigated whether perioperatively infusing low-dose buprenorphine, an opioid with anti-NMDA activity, in patients receiving remifentanil infusion prevents postoperative secondary hyperalgesia. METHODS: Sixty-four patients, undergoing remifentanil infusion during general anaesthesia and major lung surgery, were randomly assigned to receive either buprenorphine i.v. infusion (25 µg h-1 for 24 h) or morphine (equianalgesic dose) perioperatively. The presence and extent of punctuate hyperalgesia were assessed one day postoperatively. Secondary outcome variables included postoperative pain scores, opioid consumption and postoperative neuropathic pain assessed one and three months postoperatively. RESULTS: A distinct area of hyperalgesia or allodynia around the surgical incision was found in more patients in the control group than in the treated group. Mean time from extubation to first morphine rescue dose was twice as long in the buprenorphine-treated group than in the morphine-treated group: 18 vs 9 min (P=0.002). At 30 min postoperatively, patients receiving morphine had a higher hazard ratio for the first analgesic rescue dose than those treated with buprenorphine (P=0.009). At three months, no differences between groups were noted. CONCLUSIONS: Low-dose buprenorphine infusion prevents the development of secondary hyperalgesia around the surgical incision but shows no long-term efficacy at three months follow-up.

Spinal Cord Stimulation for Intractable Chronic Limb Ischemia: A Narrative Review.

Critical limb ischemia (CLI) is the most severe form of peripheral arterial disease, significantly impacting quality of life, morbidity and mortality. Common complications include severe limb pain, walking difficulties, ulcerations and limb amputations. For cases of CLI where surgical or endovascular reconstruction is not possible or fails, spinal cord stimulation (SCS) may be a treatment option. Currently, SCS is primarily prescribed as a symptomatic treatment for painful symptoms. It is used to treat intractable pain arising from various disorders, such as neuropathic pain secondary to persistent spinal pain syndrome (PSPS) and painful diabetic neuropathy. Data regarding the effect of SCS in treating CLI are varied, with the mechanism of action of vasodilatation in the peripheral microcirculatory system not yet fully understood. This review focuses on the surgical technique, new modalities of SCS, the mechanisms of action of SCS in vascular diseases and the parameters for selecting CLI patients, along with the clinical outcomes and complications. SCS is a safe and effective surgical option in selected patients with CLI, where surgical or endovascular revascularization is not feasible.

Transforaminal Steroid Injection After Dorsal Root Ganglion Pulsed Radiofrequency (DRG-PRF): Impact on Pain Intensity and Disability.

INTRODUCTION: Dorsal root ganglion pulsed radiofrequency (DRG-PRF) is frequently used for the treatment of chronic lumbar radicular pain with good outcomes in terms of pain management. Transforaminal epidural steroid injection (TFESI) is often administered immediately after DRG-PRF to increase the anti-inflammatory effects, but support for the synergic mechanism is lacking in the literature. The aim of this study was to investigate the potential role of TFESI immediately after DRG-PRF and its possible role on pain intensity and patient disability. METHODS: A database of patients who underwent DRG-PRF with or without TFESI immediately after DRG-PRF was retrospectively analysed; propensity score matching was applied to the analysis to reduce possible bias. Pain intensity (numerical rating scale [NRS]) and Oswestry disability index (ODI) were recorded pre-operatively and at the 1- and 3-month follow-up in the two groups of patients. RESULTS: A total of 252 patients were included in this retrospective analysis, 126 patients in the DRG-PRF + TFESI group and 126 patients in the DRG-PRF group after propensity score matching. Both groups displayed a significant reduction in pain intensity (NRS score reduction; p < 0.0001) and improvement in the ODI (p < 0.0001) from baseline at the 3-month follow-up. Interestingly, the use of TFESI after DRG-PRF was not associated with any clinical benefit as no difference in NRS and ODI was found between the two groups at the 1- and 3-month follow-ups. CONCLUSIONS: Our study revealed a significant pain reduction and disability improvement after DRG-PRF in patients with lumbar radicular pain. Interestingly, no positive role of TFESI immediately after DRG-PRF was observed. These findings suggest that DRG-PRF provides substantial pain relief, and no added benefit is obtained with subsequent steroid injection. Future prospective studies with expanded follow-up periods are needed to confirm these findings.

Emergency Awake Laparotomy Using Neuraxial Anaesthesia: A Case Series and Literature Review.

Emergency laparotomy is a surgical procedure associated with significantly higher mortality rates compared to elective surgeries. Awake laparotomy under neuraxial anaesthesia has recently emerged as a promising approach in abdominal surgery to improve patient outcomes. This study aims to evaluate the feasibility and potential benefits of using neuraxial anaesthesia as the primary anaesthetic technique in emergency laparotomies. We conducted a case series involving 16 patients who underwent emergency laparotomy for bowel ischemia, perforation, or occlusion. Neuraxial anaesthesia was employed as the main anaesthetic technique. We analysed patient demographics, clinical characteristics, intraoperative details, and postoperative outcomes. The primary outcome measures included the adequacy of postoperative pain control, the incidence of postoperative complications, and mortality rates. Among the 16 patients, adequate postoperative pain control was achieved, with only 2 patients requiring additional analgesia. Postoperative complications, including sepsis, wound dehiscence, and pneumonia, were observed in seven patients (44%). The observed mortality rate was relatively low at 6% (one patient). Notably, conversion to general anaesthesia was not necessary in any of the cases, and no early readmissions were reported. Our findings highlight the feasibility and potential benefits of using neuraxial anaesthesia in emergency laparotomies. The observed low mortality rate and the avoidance of conversion to general anaesthesia suggest that neuraxial anaesthesia may be a useful alternative in emergency settings. However, the occurrence of postoperative complications in 44% of patients indicates the need for cautious patient selection and close monitoring. Further research with larger sample sizes is warranted to fully elucidate the efficacy, safety, and potential impact of this technique on patient outcomes in emergency laparotomies.

Emerging treatment for chronic migraine and refractory chronic migraine.

INTRODUCTION: Chronic migraine (CM), the suffering of 15 or more headache days with at least 8 of these migraine days, afflicts 1.3% - 5.1% of the global population. CM is the most common disorder faced by experts in tertiary headache centers. When resistant to conventional medical treatment and prophylactic medication this condition is known as refractory chronic migraine (RCM). RCM is one of the greatest challenges in headache medicine. AREAS COVERED: State-of-the-art and future medical treatments of chronic migraine include: OnabotulinumtoxinA, antiepileptic drugs (Levetiracetam, Magnesium valproate hydrate, Lacosamide, BGG-492), 5-HT agonists (Lasmiditan, NXN-188, novel delivery systems of Sumatriptan, a well-established drug treatment for acute migraine), CGRP receptor antagonists (BMS-927711), ML-1 agonists (Ramelteon), orexin receptor antagonist (MK-6096), plant-derived compound (LLL-2011) and other multitarget drugs such as Tezampanel, Tonabersat, intranasal carbon dioxide and BOL-148. The role for neuromodulation, the application of targeted electrical stimulation, will be examined. EXPERT OPINION: Medication overuse headache (MOH) is now recognized to be a major factor in many cases of both chronic and refractory chronic migraine. MOH must be addressed prior to evaluating the effectiveness of new preventative and prophylactic treatment approaches. Innovative new drugs and electrical neuromodulation are promising CM treatments. Future studies must carefully screen patients and acquire data that can lead to personalized, tailored treatment strategies.

Radiation Exposure during Fluoroscopy-Guided Ozone Chemonucleolysis for Lumbar Disc Herniation.

Introduction: Radiation exposure is a frequent drawback of spinal surgery, even if X-ray guidance plays a pivotal role in improving the accuracy and safety of spinal procedures. Consequently, radiation protection is essential to reduce potential negative biological effects. The aim of this study was to evaluate patients' radiation exposure, the radiation dose emission during fluoroscopy-guided ozone chemonucleolysis (OCN), and the potential role of patient characteristics. Methods: The radiation dose emission reports were retrospectively evaluated in patients who underwent single-level OCN for lumbar disc herniation. A generalized linear model (GLM) with a gamma distribution and log link function was used to assess the association between radiation emission and patients' characteristics such as age, sex, BMI, level of disc herniation, disc height, and site of disc herniation. Results: Two hundred and forty OCN cases were analyzed. A safe and low level of radiation exposure was registered during OCN. The median fluoroscopy time for OCN was 26.3 (19.4−35.9) seconds, the median radiation emission dose was 19.3 (13.2−27.3) mGy, and he median kerma area product (KAP) was 0.46 (0.33−0.68) mGy ⋅ m2. The resulting KAP values were highly dependent on patient variables. In particular, sex, obesity, and residual disc height < 50% significantly increased the measured KAP, while levels of disc herniations other than L5-S1 reduced the KAP values. Conclusions: The radiation exposure during OCN is low and quite similar to a simple discography. However, patient characteristics are significantly related to radiation exposure and should be carefully evaluated before planning OCN.

Critical pneumonia complicating early-stage pregnancy.

We present a case of community-acquired methicillin-resistant Staphylococcus aureus necrotizing pneumonia, Panton-Valentine leukocidin positive, in a woman at 14 weeks of pregnancy. To our knowledge, this is the first case reporting this critical lung infection occurring during an early phase of pregnancy. This case study alerts physicians to the increasing worldwide spread of these uncommon yet virulent and potentially lethal infections. In our patient, antibiotic therapy with linezolid plus rifampin started at 14 weeks of pregnancy had a successful outcome without inducing toxicity or teratogenesis in the fetus.

Optical fiber technology enables smart needles for epidurals: an in-vivo swine study.

Nowadays, epidural space identification is made by using subjective and manual techniques characterized by failure rates up to 7%. In this work, we propose a fiber optic sensor technology based needle guidance system, that is directly inspired by the most common technique currently used for epidurals; through real-time strain measurements, the fiber Bragg grating integrated inside the needle lumen is able to effectively perceive the typical force drop occurring when the needle enters the epidural space. An in vivo swine study demonstrates the validity of our approach, paving the way for the development of lab-in-a-needle systems.

Microvascular dysfunction and skeletal muscle oxygenation assessed by phase-modulation near-infrared spectroscopy in patients with septic shock.

OBJECTIVE: Sepsis is now considered a disease of the microcirculation. Little is known about the various sepsis-induced changes responsible for microvascular dysfunction. We investigated human microvascular function, regulation, oxygenation, and cellular metabolism during subacute septic shock. DESIGN AND SETTING: Prospective case-control study in a nine-bed polyvalent surgical ICU of a university hospital. PATIENTS AND PARTICIPANTS: A prospectively enrolled group of 26 patients (13 with septic shock, 13 nonseptic postsurgical patients) and 15 healthy volunteer controls. MEASUREMENTS AND RESULTS: The absolute tissue hemoglobin concentrations (oxygenated hemoglobin and deoxyhemoglobin) were measured noninvasively in arterioles, capillaries, and venules by phase-modulation near-infrared spectroscopy in the human brachioradial muscle during a series of venous occlusions and an arterial occlusion (ischemia) induced by applying a pneumatic cuff. These measurements were used to calculate tissue blood volume, postischemic hemoglobin resaturation time, microvascular compliance, and O2 consumption. Patients with sepsis had significantly higher tissue blood volume values and lower compliance than healthy controls. They also had longer postischemic hemoglobin resaturation times than the other two groups and blunted resaturation curves. O2 consumption was lower in patients with sepsis than in healthy controls. In patients with septic shock cuff-induced ischemia left O2 consumption unchanged, whereas in healthy volunteers it reduced O2 consumption to values almost matching those of patients with septic shock. CONCLUSIONS: These findings show that septic shock alters microvascular muscle function and regulation. Diminished local VO2 presumably reflects maldistribution and faulty autoregulation of local blood flow.

Immature platelet fraction in predicting sepsis in critically ill patients.

PURPOSE: To establish whether in critically ill patients without sepsis at intensive care unit (ICU) admission the percentage immature platelet fraction (IPF%) is a cellular marker predicting sepsis to verify a possible correlation between IPF% changes and manifest sepsis and describe the IPF% time course after ICU admission. METHODS: Prospective, observational 7-day study of 64 adult patients admitted to a general ICU at a University Hospital with no sepsis criteria. We measured daily IPF%, procalcitonin (PCT), C-reactive protein, platelets, white blood cell count and coagulation variables. Thirty-one patients with sepsis at ICU admission were studied as controls. RESULTS: The only variable we tested at ICU admission that predicted sepsis was plasma IPF% (p < 0.001; >4.7 %: sensitivity 56.2 % IC 37.7-73.6; specificity 90.0 % IC 73.4-97.8). IPF% and PCT values were higher for the patients who had sepsis at admission and during the study than in patients in whom sepsis never developed (IPF%: p = 0.017; PCT: p = 0.030). Among the outcome variables, logistic regression was identified as the only variable related to the development of sepsis, IPF% (r = 0.51; p = 0.004). In patients who developed sepsis IPF% was inversely correlated with platelet count (r = -0.60; p < 0.001) and had high values before sepsis became manifest, decreasing significantly on the 2nd day thereafter. CONCLUSIONS: In patients without sepsis at ICU admission IPF% increases before sepsis becomes manifest. Measuring IPF% through an easily available technology can therefore provide an early cellular marker predicting the development of sepsis.