Using the BBraun BSmartTM Pressure Manometer to Prevent Unsafe Injection Pressures During Simulated Peripheral Nerve Blockade: A Pilot Study

Background: Peripheral nerve injury during regional anaesthesia may result from accidental intraneural placement of the needle, or forceful needle nerve contact. Intraneural injections are associated with increased resistance to injection, typically >15 psi. The BBraun BSmart™ is an inline mechanical manometer, offering a visual display of injection pressures. Objective: The primary objective of this study was to determine if using the BBraun BSmartTM manometer successfully prevents 90% of anaesthetists and anaesthetic assistants from injecting at pressures > 15 psi during simulated nerve block. Methods: This was a prospective observational study involving anaesthetists and anaesthetic assistants. Two 20 ml injections were performed by each participant, once when the BBraun BSmartTM manometer was obscured from view, and once with the manometer visible. A PendoTech PressureMATTMS recorded injection pressures. Results: 39 participants completed the study, with a total of 78 injections recorded. During the study, 32 peak pressures during the 78 procedures were recorded above the recommended upper limit of 15 psi, 41% of the total injections. The peak pressure rose above 15 psi in 24/39 (62%) injections when the BBraun Bsmart™ manometer was obscured, but only in 8/39 (21%) injections when the manometer was visible. Conclusion: The BBraun Bsmart™ manometer did not successfully prevent 90% of anaesthetists or anaesthetic assistants from injecting at unsafe pressures. However, using the BBraun BSmart™ did reduce the number of unsafe injection pressures generated by participants. When utilised in conjunction with PNS and ultrasound guidance, this may offer additional safety during peripheral nerve blockade.

Comparison of Ropivacaine-Fentanyl with Bupivacaine-Fentanyl for Labour Epidural Analgesia

Background: Bupivacaine with opioid is commonly used for labour epidural analgesia. Ropivacaine is considered as an alternative to bupivacaine due to its lower cardiovascular complications. However, there is a controversy regarding the efficacy of these drugs as some studies suggest equivalent action, whereas others report that ropivacaine produces less motor blockade. The study aimed to compare the effect of ropivacaine-fentanyl and bupivacaine-fentanyl for labour analgesia. Materials and Methods: The prospective randomized study was performed on 60 parturients, divided into two groups of 30 subjects each. Group I received 10ml of bupivacaine 0.1% + fentanyl 2µg/ml and Group II received 10ml of ropivacaine 0.1% + fentanyl 2µg/ml by epidural catheter. Pre-anaesthetic evaluation was performed on all the participants and all were administered metoclopramide 0.25mg/kg and ondansetron 0.08-0.1mg/kg intravenously as premedication. The baseline and post anaesthesia systolic, diastolic blood pressure, heart rate, VAS score, degree of motor block, sedation and APGAR score of the baby were recorded. The data were tabulated and statistically analyzed. Results: When compared, there was no significant difference in systolic/diastolic blood pressure in two groups except at 360 min where diastolic pressure was low in group II. Significantly higher heart rate at 30 min (P=0.0003), 120 min (0.006), and 300 min (P=0.001) was observed in group I subjects. VAS score was significantly less at 180 min (P=0.019) and 300 min (P=0.019) in group II. Adverse effects such as fetal bradycardia, nausea/vomiting and hypotension observed were clinically insignificance when compared in two groups. Conclusion: Bupivacaine and ropivacaine produce an equal degree of analgesia and hemodynamic stability in 0.1% of concentration when added with 2µg/ml fentanyl . However, heart rate was well maintained with lower VAS scores in group II receiving ropivacaine. No significant difference in the side effects between the two groups. Hence, Ropivacaine can be used as a safe alternative to bupivacaine for labour epidural analgesia.

Evaluation of Efficacy of Free Opioid Anesthesia for Laparoscopic Cholecystectomy: A Prospective, Randomized Double-blinded Study

Objectives: To evaluate efficacy and side effects of free opioid anesthesia for laparoscopic cholecystectomy. Methods: A prospective study was performed on 94 patients undergoing laparoscopic cholecystectomy in Military Hospital 103 from May 2018 to February 2019. These patients were randomly allocated into two groups: patients in FOA (free - opioid anesthesia) group were administered lidocaine (2 mg/kg before induction and 1.5 mg/kg/h for maintenance), magnesium (30 mg/kg before induction and 1.5 g infusion for maintenance) combined with Intravenous (IV) injection of ketamine (0.5 mg/kg), and ketorolac (30 mg); while patients in OA group (opioid anesthesia) were provided with IV fentanyl (5 mcg/kg for induction and 1.5 mcg/kg every 30 minutes for maintenance of anesthesia). Both groups received total intravenous anesthesia by propofol. The depth of anesthesia was monitored by the entropy module during surgery. Neuromuscular blockade was reversed by sugammadex 2 mg/kg at the end of surgery. The postoperative analgesia was delivered using IV fentanyl for 48 to 72 hours. Visual Analog Scale (VAS) score was measured 10 mins, 20 mins, 1 hour, 2 hours and 3 hours after surgery. Results: All patients had an excellent quality of anesthesia with RE (Respond Entropy), SE (State Entropy) always under 60 from induction to abdominal closure without intraoperative awareness and postoperative recall of the operation; 100% of the patients were extubated immediately after surgery. In the first three postoperative hours fentanyl consumption in Group FOA was significantly lower than in Group OA (31.91 ± 3.98 mcg versus 34.47 ± 7.17 mcg, p=0,035). In the OA group, the rate of intraoperative hypotension was higher compared to its counterpart. Despite the higher risk of hypersalivation, group FOA had a significantly lower incidence of nausea and vomiting. Conclusion: Free opioid anesthesia provided adequate sedation and amnesia and may be an alternative approach to opioid anesthesia for laparoscopic cholecystectomy. Patients under free opioid anesthesia experienced a lower incidence of intraoperative hypotension, lower rate of nausea, vomiting and lower demand for analgesia in the early postoperative period (0 - 3 h) compared to those receiving opioid anesthesia.

Dexamethasone Versus Magnesium Sulfate as an Adjuvant to Local Anesthetics in the Ultra-Sound Guided Injection of Piriformis Muscle for the Treatment of Piriformis Syndrome

Background: Piriformis Syndrome (PS) is an underdiagnosed cause of buttock, thigh and leg pain, most probably because it is thought to be a rare cause of sciatica. PS is widely believed to be myofascial in origin. Materials and Methods: This prospective, randomized, controlled, double-blind study was conducted at the pain management department. 50 patients aged from 20 to 60 years old were included in this study. The selected patients were randomly allocated into 2 groups containing 25 patients each; Group D received a total of 5 mL which included 2mL lidocaine 2%, 2mL (8 mg) dexamethasone and 1mL normal saline 0.9%, and Group M received a total of 5mL which included 2mL lidocaine 2%, 3mL magnesium sulphate (MgSO4) (2.5%) . Patients demographic characteristics, baseline physical examination findings of the patients as well as the duration of pain were all recorded. Patients were re-assessed immediately after injection, 1 week, 1 month, and 3 months after the injection. Numeric Rating Scale (NRS) values were used at each evaluation time to assess the pain, while patients were in sitting, standing, and lying positions. All patients were assessed immediately and for 4 hours post-injection for any side effects related to the drugs used. Results: In the pre-injection time, immediately after and 1 week after injection, there were no statistically significant differences between groups D and M in pain values. While, on comparison between both groups, group M, was significantly better than group D, in NRS values 1 month and 3 months after injection. In group D, pain score values were significantly better immediately, 1 week, and 1 month after injection compared to the pre-injection values, while these values were not significantly different 3 months after injection compared with the pre-injection values. In group M, pain score values were significantly better immediately, 1 week, 1 month, and 3 months after injection compared to the pre-injection values. Conclusion: Magnesium sulfate was more effective, especially for long term pain relief (3 months) when compared to dexamethasone as they were used as adjuvants to lidocaine, if injected into the piriformis muscle (PM) guided by ultrasound in the management of PS refractory as initial conservative treatment.

The Role of an Ultrasound-Guided Block of the Deep Plane of the Serratus Muscle in a Modified ERAS Protocol for Cardiac Surgery

To date, the use of multimodal techniques can allow substantial opioid-sparing and can reduce pain by using the local and systemic effects of different types of analgesics. Aims: This case report describes a modified ERAS protocol specific for cardiac surgery with the ultrasound-guided block of the deep plane of the serratus muscle (SAP deep block) in a multimodal opioid-sparing approach. \ Two male patients, aged 62 and 67, undergoing elective mini-invasive off-pump Cardiopulmonary Bypass Grafting (CPB), were treated with an opioid-sparing multimodal anesthesiological approach based on the continuous ultrasound-guided SAP deep block. The continuous ultrasound-guided SAP deep block alone can be used in the case of mini-left thoracotomy off-pump cardiopulmonary bypass grafting implementing a multi-modal opioid-sparing strategy. It seems effective in obtaining good (2 hours) weaning from mechanical ventilation, quick (36 hours) discharge from post-operative intensive care, and good post-operative pain control (NRS < 5) even in elderly and frail patients.

Color Spectrographic Analysis of Respiratory Sounds: A Promising Technology for Respiratory Monitoring

Background: The need for reliable respiratory monitoring has increased in recent years with the frequent use of opioids for perioperative pain management as well as a high prevalence of patients suffering from respiratory comorbidities. Objective: Motivated by the success of acoustical color spectrographic techniques in other knowledge domains, we sought to build proof-of-concept systems for the computer-based color spectrographic analysis of respiratory sounds, recorded from various sites. Methods: We used a USB miniature electret microphone and a Windows-based color spectrographic analysis package to obtain color spectrograms for breath sound recordings from the neck, from an oxygen mask, from the ear canal, and from a leak-free microphone pneumatically connected to the cuff of a laryngeal mask airway. Results: Potentially useful color spectrographic displays were obtained from all four recording sites, although the spectrograms obtained varied in their characteristics. It was also found that obtaining high-quality color spectrograms requires attention to a number of technical details. Conclusion: Color spectrographic analysis of respiratory sounds is a promising future technology for respiratory monitoring.

Analgesic Effect of Nebulized Versus Intravenous Fentanyl for Pain Relief of Limb Fracture: A Double-Blind Clinical Trial

Background:More than half of the patients attending emergency centers need analgesics. Injectable analgesics are currently the most common pain control strategy, but entail complications. Fentanyl is one of the most commonly used pain-relief opiates available in various forms.Objective:The present study aims to compare analgesic effects of nebulized against intravenous fentanyl for controlling pain due to limb fracture.Method:The present double-blind clinical trial recruited 213 patients presenting with fractured limbs to emergency departments. The first group of patients received 1 micg/kg of intravenous fentanyl citrate from a solution of 50 micg/ml and 5 ml of normal saline in nebulized form (group A), and the second group intravenously received 5 ml of normal saline and 4 micg/kg of 50 micg/ml solution of fentanyl citrate in nebulized form, whose volume reached 5 ml with the addition of normal saline (group B). Then, pain level was frequently measured and compared in the two groups for 20 minutes.Results:The results obtained showed reduced pain level in both the groups. However, point-by-point comparison of pain in the two groups revealed significantly greater pain reduction in intravenous fentanyl group (P<0.001). The need for adjuvant pain relief medication was 8.3% in intravenous fentanyl group and 24% in nebulized fentanyl group, with a significant difference between the two groups (P=0.002).Conclusion:According to the results, although nebulized fentanyl is effective in controlling pain due to limb fracture, it was less effective than intravenous type, and unable to control pain in many cases.