Preservative-free Lidocaine Research Articles

Clinical effects and pharmacokinetics of nebulized lidocaine in healthy horses.

BackgroundNebulized lidocaine appears promising as a novel corticosteroid-sparing therapeutic for equine asthma, but its safety and pharmacokinetic behavior have yet to be confirmed.ObjectiveTo describe the effect of nebulized lidocaine on upper airway sensitivity, lung mechanics, and lower respiratory cellular response of healthy horses, as well as delivery of lidocaine to lower airways, and its subsequent absorption, clearance, and duration of detectability.AnimalsSix healthy university- and client-owned horses with normal physical examination and serum amyloid A, and no history of respiratory disease within 6 months.MethodsProspective, descriptive study evaluating the immediate effects of 1 mg/kg 4% preservative-free lidocaine following nebulization with the Flexineb®. Prior to and following nebulization, horses were assessed using upper airway endoscopy, bronchoalveolar lavage, and pulmonary function testing with esophageal balloon/pneumotachography and histamine bronchoprovocation. Additionally, blood and urine were collected at predetermined times following single-dose intravenous and nebulized lidocaine administration for pharmacokinetic analysis.ResultsUpper airway sensitivity was unchanged following lidocaine nebulization, and no laryngospasm or excessive salivation was noted. Lidocaine nebulization (1 mg/kg) resulted in a mean epithelial lining fluid concentration of 9.63 ± 5.05 μg/mL, and a bioavailability of 29.7 ± 7.76%. Lidocaine concentrations were higher in epithelial lining fluid than in systemic circulation (Cmax 149.23 ± 78.74 μg/L, CELF:Cmaxplasma 64.4, range 26.5–136.8). Serum and urine lidocaine levels remained detectable for 24 and 48 h, respectively, following nebulization of a single dose. Baseline spirometry, lung resistance and dynamic compliance, remained normal following lidocaine nebulization, with resistance decreasing post-nebulization. Compared to the pre-nebulization group, two additional horses were hyperresponsive following lidocaine nebulization. There was a significant increase in mean airway responsiveness post-lidocaine nebulization, based on lung resistance, but not dynamic compliance. One horse had BAL cytology consistent with airway inflammation both before and after lidocaine treatment.ConclusionsNebulized lidocaine was not associated with adverse effects on upper airway sensitivity or BAL cytology. While baseline lung resistance was unchanged, increased airway reactivity to histamine bronchoprovocation in the absence of clinical signs was seen in some horses following nebulization. Further research is necessary to evaluate drug delivery, adverse events, and efficacy in asthmatic horses.

Pupil Dilation by Intracameral Injection of Preservative Free 1% Lidocaine and Topical Mydriatics in Phacoemulsification Cases: A Comparative Study

Purpose: To compare the results of pupil dilation by an intracameral injection of preservative free 1% lidocaine with conventional topical mydriatics during phacoemulsification cataract surgery. Comparison was also done for simultaneous anaesthetic effect between intracameral lidocaine and topical mydriatics. Methods: A randomized, comparative interventional study was conducted. The study included 50 patients who underwent phacoemulsification and intraocular lens implantation surgery and were divided in two groups. One group was given topical mydriatics (25 eyes) preoperatively and other intracameral lidocaine (25 eyes) at commencement of surgery to dilate the pupil. The topical group received 3 drops of tropicamide 0.8% and phenylephrine 5% eye drops 15 minutes apart starting 45 minutes before surgery. The intracameral group received preservative-free lidocaine 1% (0.2 to 0.3 mL) injected just before the procedure began. In both groups, the horizontal pupil diameter was measured before and after pupil dilation using the same caliper. Total surgical time, need for a supplement mydriatic agent during the surgery and subjective surgical performance were recorded. Any adverse ocular and systemic effects between two groups were also compared. Results: The mean age, sex, cataract grading, baseline horizontal pupil diameter and mean surgerical time were similar between the topical and intracameral group. The mean pupil dilation was 4.62 ± 0.96 mm in the intracameral group and 4.76 ± 0.75 mm in the topical group. There was no statistically significant difference between the two groups (P value =0.57).There was no significant difference between groups in the overall subjective surgical performance (P=0.72). No patient in any group required supplementary intracameral mydriatic injection. Conclusion: Intracameral lidocaine is a safe, effective and reliable alternative to topical mydriatic for pupil dilation with added advantages of fast postoperative recovery and is also ....

Evaluation of the in vitro effects of local anesthetics on equine chondrocytes and fibroblast-like synoviocytes.

To investigate the in vitro effects of clinically relevant concentrations of the local anesthetics (LAs) bupivacaine, lidocaine, lidocaine with preservative (LP), mepivacaine, and ropivacaine on equine chondrocyte and fibroblast-like synoviocyte (FLS) viability. Chondrocytes and FLSs of the metacarpophalangeal joints of 4 healthy adult horses. Viability of chondrocytes and FLSs was determined with 3 assays: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase (LDH), and trypan blue (TB) exclusion (only FLS). Viability was assessed after 30- and 60-minute exposures to 0.0625%, 0.125%, and 0.25% bupivacaine; 0.25%, 0.5%, and 1% lidocaine; 0.25%, 0.5%, and 1% LP; 0.25%, 0.5%, and 1% mepivacaine; and 0.125%, 0.25%, and 0.5% ropivacaine. Viability of chondrocytes was significantly decreased with exposure to 0.25% bupivacaine, 1% lidocaine, 1% LP, 1% mepivacaine, and 0.25% ropivacaine. Viability of FLSs was significantly decreased with exposure to 0.25% bupivacaine, 1% mepivacaine, 1% LP, and 0.5% ropivacaine. Clinically relevant concentrations of LAs had in vitro time- and concentration-dependent cytotoxicity for chondrocytes and FLSs isolated from the metacarpophalangeal joints of healthy horses. Bupivacaine was more toxic to chondrocytes than lidocaine, mepivacaine, and ropivacaine, whereas bupivacaine, LP, mepivacaine, and ropivacaine were more toxic to FLSs than preservative-free lidocaine. Several LAs may negatively affect chondrocyte and FLS viability.

One-Year Randomized Comparison of Safety and Efficacy of Trabeculectomy with Mitomycin C Sub-Tenon Injection versus Mitomycin C-Infused Sponges

To compare the safety and efficacy of sub-Tenon injection of mitomycin C (MMC) with application of MMC-infused sponges during trabeculectomy. Single-center randomized clinical trial. A total of 56 eyes of 49 patients with open-angle glaucoma were included in this clinical trial. In this single-center randomized clinical trial, 56 eyes of 49 patients underwent trabeculectomy with MMC for primary open-angle glaucoma. Patients were randomized into 2 groups. The injection group received a sub-Tenon injection of 0.15 ml of 0.01% MMC diluted with preservative free lidocaine 2% (n= 27). In the sponges group, sponges soaked in 0.02% MMC were applied under the Tenon's capsule and the scleral flap for 2 minutes (n= 29). Intraocular pressure, endothelial cell count, best-corrected visual acuity, and number of intraocular pressure (IOP)-lowering medications were assessed before surgery and 1 week; 1, 3, and 6 months; and 1 year after surgery. Complete success was defined as IOP of 14 mmHg or less without medication. Bleb morphologic features were assessed using the Indiana Bleb Appearance Grading Scale bleb grading system. Intraocular pressure reduction was the primary outcome. Bleb morphologic features and endothelial cell counts (ECCs) were secondary outcomes. Mean IOP in the sponges group decreased from 30.5 ± 7.4 mmHg at baseline to 12.6 ± 5.9 mmHg at 1 year (P < 0.001); in the injection group, IOP decreased from 29.3 ± 6.8 mmHg at baseline to 12.7 ± 4.3 mmHg at 1 year (P < 0.001). No difference in IOP between the 2 groups was noted at any visit (P < 0.001). Surgical success was 81.5% and 82.8% in the injection and sponges groups, respectively, at 1 year. Mean ECC values were unchanged from baseline to 1 year after surgery for both groups (P= 0.444). Complication rates were similar in the 2 groups. Bleb morphologic features showed differences in the appearance and grading of the blebs between the 2 groups at 1 year, showing larger extent, lower height, and less vascularization in the injection group. Sub-Tenon injection of MMC during trabeculectomy seems to be as safe and as efficacious as conventional application of MMC with sponges at 1 year after surgery. Bleb morphologic features show notable differences that may suggest a better long-term outcome.

M400 MANAGING A CASE OF REPORTED LOCAL LIDOCAINE ALLERGY IN A PREGNANT WOMAN DURING COVID-19 PANDEMIC

We report how we diagnosed and managed a case of reported local anesthetic allergy in a high-risk pregnant woman during the COVID-19 pandemic via telemedicine. We were consulted by the obstetrician for lidocaine allergy in advance of a spinal block for an elective cesarean section in a 23-year-old woman at 34 weeks of gestation. The patient had a past medical history of ulcerative colitis and a surgical history of having a colectomy and ostomy. The patient reported a previous episode of localized hives and swelling shortly after undergoing a dental procedure that was thought to be secondary to her receiving a lidocaine injection. She denied cardiopulmonary and gastrointestinal symptoms, anxiety or delayed reactions. Therefore IgE-mediated hypersensitivity was possible. Due to the COVID-19 pandemic, we conducted the initial assessment and the subsequent planning with multiple providers involved in the case through a Telehealth route. At 38 weeks of gestation, in a pre-delivery room with fetal monitoring, the patient passed both skin prick and intradermal testing for lidocaine (10mg/ml), preservative free lidocaine (10 mg/ml) and preservative free bupivacaine (2.5 mg/ml). Subsequently, she passed a subcutaneous skin challenge with 1 ml of preservative free lidocaine (10 mg/ml). A few hours later, she delivered a baby uneventfully by cesarean section under spinal block using local preservative free lidocaine. We report the management of reported lidocaine allergy on a pregnant patient during COVID-19 pandemic via both telemedine and pre-delivery on-site skin testing. We successfully removed the label of lidocaine allergy immediately before her delivery.

Effects of Lidocaine on Mitomycin C Cytotoxicity

Intra-Tenon or subconjunctival injection of a solution of mitomycin C (MMC) and 1% preservative-free lidocaine (as an anesthetic) has gained popularity for its use in trabeculectomy, a filtering surgery for glaucoma. To our knowledge, no studies have analyzed the impact of lidocaine on the cytotoxic effects of MMC in this setting. This study was conducted to evaluate invitro fibroblast cytotoxicity to a solution of MMC (0.2 mg/ml) and 1% preservative-free lidocaine. Experimental study. Nonhuman subject research. Cultured human conjunctival fibroblasts were incubated in phosphate-buffered saline (PBS) (control), MMC (0.2 mg/ml), a mixture of 0.2 mg/ml MMC+ 1% preservative-free lidocaine, or 1% preservative-free lidocaine. Samples were taken at 2, 5, 10, 30, and 60 minutes, and a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay with photoabsorbance testing was used to assess conjunctival cell viability. Mean photoabsorbance. Mean photoabsorbance across all time intervals was 0.680 for solutions incubated in PBS, 0.642 for MMC, 0.612 for MMC+ 1% preservative-free lidocaine, and 0.605 for 1% preservative-free lidocaine. A 2-way analysis of variance analyzing solution, time, and solution-time interaction on photoabsorbance showed that PBS was least cytotoxic and an optimal control for this study. Tukey post hoc comparisons showed that MMC was more cytotoxic than PBS (P < 0.001). However, both MMC+ 1% preservative-free lidocaine and 1% preservative-free lidocaine were more cytotoxic than MMC and PBS (P < 0.01 for all). No significant differences in cytotoxicity comparing lidocaine-containing solutions were observed. In this invitro study, we found an increase in cytotoxicity when MMC (0.2 mg/ml) was combined with 1% preservative-free lidocaine. We note that lidocaine did not inhibit MMC cytotoxicity and exhibited a significant cytotoxic effect on its own.

Effect Of Intracameral Phenylephrine And Ketorolac 1.0%/0.3% On Intraoperative Pain And Opioid Use During Cataract Surgery.

PurposeTo compare the effect of Omidria (phenylephrine and ketorolac 1.0%/0.3%) vs epinephrine on pain reduction and opioid usage during cataract surgery.Patients and methodsSixty patients at a single center underwent femtosecond laser (FLACS) or conventional phacoemulsification under topical lidocaine gel anesthesia and intracameral preservative-free lidocaine 1%. Eligible participants were prospectively assigned to receive either intracameral phenylephrine and ketorolac 1.0%/0.3% or intracameral epinephrine. All patients received standardized pre- and post-operative topical therapy. Intravenous (IV) fentanyl was administered for ocular discomfort in patients who complained of intraoperative pain. Outcome measures included both pain (measured by mean visual analog scale (VAS) pain scores from 0 (no pain) to 10 (extreme pain)) and the use of IV fentanyl during surgery. A composite endpoint identified “responders” as being patients who: (1) did not require fentanyl and (2) experienced no to minimal pain (VAS score ≤ 3).ResultsForty-one patients were in the phenylephrine and ketorolac 1.0%/0.3% (study) group and 19 were in the epinephrine (control) group. Mean VAS pain scores were significantly (48.9%) lower in the study group than the control group (2.3 vs 4.5; P < 0.0001). The proportion of patients with VAS scores ≤ 3 was significantly greater in the study group (85.0%) than the control group (31.6%) (P < 0.0001). A smaller proportion of patients required intraoperative fentanyl in the study group compared to the control group (9.8% vs 42.1%; P = 0.006). For the composite endpoint, patients receiving phenylephrine and ketorolac 1.0%/0.3% were 94% less likely to require fentanyl or to have moderate-to-severe pain (pain VAS ≥ 4; OR, 0.06; 95% CI 0.02–0.24) than patients receiving epinephrine.ConclusionOur results suggest that the routine use of intracameral phenylephrine and ketorolac 1.0%/0.3% during cataract surgery can significantly reduce patient pain as well as the need for opioids.

A Comparative Study to Evaluate the Efficacy of three Different Doses of Intraoperative Infusion of Intravenous Preservative Free Lidocaine in Patients Undergoing Laparoscopic Cholecystectomy

A Comparative Study to Evaluate the Efficacy of three Different Doses of Intraoperative Infusion of Intravenous Preservative Free Lidocaine in Patients Undergoing Laparoscopic Cholecystectomy

Caudal Anaesthesia in Ambulatory Colonoscopy: Lidocaine Only vs. Lidocaine/fentanyl Combination

Background: This study aimed to compare the analgesic effects of caudal anaesthesia in patients undergoing ambulatory colonoscopy using lidocaine only or lidocaine/fentanyl combination. Methods: Fifty-one consecutive adult patients scheduled for colonoscopy participated in the study. Participants were randomly allocated into two equal groups (A and B). Caudal anaesthesia was instituted in both groups with 1.5% preservative free lidocaine (19.4 ml); 0.6 ml of normal saline was added in Group A and 30 mcg of fentanyl made to 0.6 ml in Group B. The time of onset and height of caudal block, Numeric Pain Rating Scale (NPRS) score at different stages during colonoscopy were evaluated and compared. The number of patients requiring rescue analgesia (fentanyl/midazolam) were also evaluated and compared. Results: Twenty-six patients in the saline-lidocaine group (A) and twenty-five patients in the fentanyl-lidocaine group (B) completed the study. The mean and standard deviation of the caudal block onset time (minute) in group A was 11.71 ± 4.26 comparable to group B which was 13.50 ± 4.85, p=0.15. The median NPRS while navigating the splenic flexure was 2 in group A and 3 in group B; and while navigating the hepatic flexure it was 5 in group A and 3 in group B. But p values are 0.285 and 0.031 respectively. Rescue analgesia was employed in fewer number of patients in group B (16%) compared to group A (34.6%). Conclusion: Caudal epidural block with lidocaine/fentanyl combination provided superior, safe and satisfactory anaesthesia for ambulatory colonoscopy.

A comparison of patient pain and visual outcome using topical anesthesia versus regional anesthesia during cataract surgery.

PurposeThe purpose of this study was to compare the level of patient pain during the phacoemulsification and implantation of foldable intraocular lenses while under topical, intracameral, or sub-Tenon lidocaine.Patients and methodsThis was a retrospective study. Three hundred and one eyes subjected to cataract surgery were included in this study. All eyes underwent phacoemulsification surgery and intraocular lens implantation using topical, sub-Tenon, or intracameral anesthesia. The topical group received 4% lidocaine drops, and the intracameral group received a 0.1–0.2 cc infusion of 1% preservative-free lidocaine into the anterior chamber through the side port combined with topical drops of lidocaine. The sub-Tenon group received 2% lidocaine. Best-corrected visual acuity, corneal endothelial cell loss, and intraoperative pain level were evaluated. Pain level was assessed on a visual analog scale (range 0–2).ResultsThere were no significant differences in visual outcome and corneal endothelial cell loss between the three groups. The mean pain score in the sub-Tenon group was significantly lower than that in the topical and intracameral groups (P=0.0009 and P=0.0055, respectively). In 250 eyes without high myopia (< −6D), there were no significant differences in mean pain score between the sub-Tenon and intracameral groups (P=0.1417). No additional anesthesia was required in all groups.ConclusionIntracameral lidocaine provides sufficient pain suppressive effects in eyes without high myopia, while sub-Tenon anesthesia is better for cataract surgery in eyes with high myopia.

Challenges in the management of intraocular parasitic infections

Parasitic worms in eye is something which is not very uncommon these days. People who eat undercooked food and have pets at home are at more risk to have parasitic infections. Chemoparalysis has been reported in literature using either viscoelastics or preservative free lidocaine (intracamerally) to paralyze the worms that help in retrieval, but still one can face tricky situations while managing such conditions. Importance lies in the management of such cases as it can be really challenging at times and no report exists in the literature which mentions the importance of topical lidocaine along with viscoelastics or preservative free lidocaine for retrieval of the worm.

A comparative evaluation of magnesium sulphate and nitroglycerine as potential adjuncts to lidocaine in intravenous regional anaesthesia.

Introduction:This randomized control trial was carried out to evaluate and compare the efficacy of magnesium sulphate and nitroglycerine (NTG) as adjuncts to lidocaine in intravenous regional anesthesia (IVRA).Materials and Methods:Seventy-five, ASA grade I and II patients, aged between 20–50 years, scheduled for hand and forearm surgery were selected and entered randomly into three study groups. Patients in group C received 3 mg/kg of preservative free lidocaine 2% diluted with saline to a total volume of 40 ml. Patients in group M received 3 mg/kg of preservative free lidocaine 2% mixed with 6 ml of 25% magnesium sulphate (1.5 g) diluted with saline to a total volume of 40 ml. Patients in group N received 3 mg/kg of preservative free lidocaine 2% mixed with 200 μg of nitroglycerine diluted with saline to a total volume of 40 ml. Sensory and motor block onset and recovery time, tourniquet pain onset time, intraoperative fentanyl requirement, the total number of patients requiring rescue analgesia and the time to first analgesia requirement, intra-operative and postoperative degree of analgesia were evaluated.Results:The sensory and motor block onset times were shorter in group M and N as compared to group C (P- = 0.004, 0.0036 for sensory block, 0.021, 0.038 for motor block. The mean time of onset of sensory block was earliest in group M and the mean time of onset of motor block was earliest in group N. Mean time of onset of tourniquet pain in the three groups was similar in groups M and N. The sensory and motor block recovery time were significantly prolonged in M and N group as compared to group C (P < 0.001). Intraoperative fentanyl requirement (P value– = 0.041), the total number of patients requiring rescue analgesia (P value = 0.009) and the time to first analgesia requirement (P value = 0.038) were lower in group M.Conclusion:The addition of both magnesium suphate and nitroglycerin (NTG) to lidocaine for intravenous regional anesthesia (IVRA) leads to early onset of sensory block and prolonged postoperative analgesia, with no side effects.

Transforaminal Epidural Injections in Chronic Lumbar Disc Herniation: A Randomized, Double-Blind, Active-Control Trial

Background: The estimated prevalence of lumbar radiculopathy has been described as 9.8 per 1,000 cases of low back pain. There are various surgical and nonsurgical modalities for treating lumbar disc herniation or radicular pain, including epidural injections. Epidural injection administration routes include transforaminal, interlaminar, and caudal approaches. The transforaminal approach requires the smallest volume to reach the primary site of pathology. Systematic reviews have yielded highly variable results, but a recent systematic review showed no significant difference among the 3 approaches. Study Design: A randomized, controlled, double blind, active control trial. Setting: An interventional pain management practice, a private specialty referral center in the United States. Objectives: To assess the effectiveness of transforaminal epidural injections of local anesthetic with or without steroids in managing chronic low back and lower extremity pain in patients with disc herniation and radiculitis. Methods: One hundred twenty patients were randomly assigned to 2 groups: Group I received 1.5 mL of 1% preservative-free lidocaine, followed by 0.5 mL of sodium chloride solution. Group II received 1% lidocaine, followed by 3 mg, or 0.5 mL of betamethasone. The sodium chloride solution and betamethasone were either clear liquids or were provided in opaquecovered syringes. Outcomes Assessment: The primary outcome measure was significant improvement (at least 50%) measured by the average Numeric Rating Scale (NRS) and the Oswestry Disability Index 2.0 (ODI). Secondary outcome measures were employment status and opioid intake. Results: At 2 years there was significant improvement in all participants in 65% who received local anesthetic alone and 57% who received local anesthetic and steroid. When separated into non-responsive and responsive categories based on initial relief of at least 3 weeks with 2 procedures, significant improvement (at least 50% improvement in pain and function) was seen in 80% in the local anesthetic group and 73% in the local anesthetic with steroid group. Limitations: Presumed limitations of this evaluation include the lack of a placebo group. Conclusion: Transforaminal epidural injections of local anesthetic with or without steroids might be an effective therapy for patients with disc herniation or radiculitis. The present evidence illustrates the lack of superiority of steroids compared with local anesthetic at 2-year follow-up. Key words: Chronic low back pain, transforaminal epidural injections, disc herniation, radiculitis, lower extremity pain, local anesthetic, steroids

The effect of intracameral anesthesia on macular thickness and ganglion cell-inner plexiform layer thickness after uneventful phacoemulsification surgery: prospective and randomized controlled trial

To evaluate the effect of intracameral lidocaine anesthesia on macular thickness and macular ganglion cell-inner plexiform layer (GC-IPL) thickness following uneventful phacoemusification in healthy subjects. This is a prospective, randomized and double- masked study. One hundred eyes of 74 consecutive patients were randomized to receive intracameral preservative-free lidocaine 1% (intracameral lidocaine group) or intracameral injection of balanced salt solution (sham injection group) at the time of the phacoemulsification surgery. Preoperative and postoperative macular thickness analyses with spectral domain optical coherence tomography (SD-ODT) were performed and the results between the two groups were compared. Postoperatively, both the central foveal thickness (CFT) and the thickness of perifoveal macula were significantly improved in both groups (p < 0.001). There was no statistically significant difference between CFT and the inner and outer macular zone thicknesses of the two groups at any follow-up time. In both groups, GC-IPL thickness was significantly increased at the first week and first month visits (p < 0.001). There was no statistically significant difference between GC-IPL thickness measurements of the two groups at any follow-up time. The current study demonstrated that supplementary intracameral lidocaine 1% did not cause more macular thickening than the intracameral sham injection during a follow-up period of 3months. The present study also showed a tendency for a transient increase in high definition SD-OCT-based GC-IPL thickness measurements within a few months following cataract surgery under both intracameral lidocaine anesthesia and intracameral sham injection.

A Study of the Efficacy of Cardiac Antidysrhythmic Drugs in Attenuating Haemodynamic Responses to Laryngoscopy and Endotracheal Intubation in the Black Population

Background: Laryngeal, tracheal and bronchial receptors are stimulated by mechanical and chemical irritants during laryngoscopy and endotracheal intubation. That almost always triggers powerful cardiovascular responses. Various attempts have been made to attenuate these responses. The aim of this study was to compare the efficacy and safety of cardiac antidysrhythmic drugs lidocaine, diltiazem and esmolol in the attenuation of cardiovascular responses to endotracheal intubation in the Black normotensive population. Patients and Methods: A randomized controlled trial was conducted in 160 adult patients of ASA physical status I or II undergoing various elective surgeries. The patients were randomly divided into four groups of 40 patients in each group - C, L, D, and E. Group - “C” received no drug (control) as placebo, group -“L” received 1.5 mg kg-1 preservative free lidocaine, group -“D” received 0.2 mg kg-1 diltiazem, and group-“E” received 2mg kg-1 esmolol IV. Group “C”, “D” and “E”, “L” one and two minutes before intubation. Changes in heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were measured and then compared within and between groups. Rate pressure product (RPP) was calculated and evaluated as well. Patients were also observed for any complications. Result: There was a significant increase in SBP, DBP, HR, MAP and RPP from the base line in control group “C” at 1 minute with onward decreases at 3 and 5 minutes respectively after intubation. Percentage change in haemodynamic variables in groups C, L, D and E at 1 minute are as follows: SBP= 23.58%, 11.84%, 9.64% and 9.9%, DBP= 18.73%, 18.89%, 11.93% and 10.40%, HR= 30.45%, 26.00%, 7.01% and 1.50%; MAP= 20.80%, 15.89%, 10.90 and 10.20%; RPP= 61.44%, 40.86%, 17.26% and 11.68% respectively. Only patients receiving placebo had increased SBP, DBP, HR, MAP and RPP values after intubation compared with baseline values (p < 0.05). Conclusions: Given the difference in the pharmacological mechanisms of these drugs, the prophylactic therapy with 2mg kg-1 esmolol is significantly more effective and safe for attenuating haemodynamic changes to laryngoscopy and tracheal intubation, without producing increased risk of hypertension in the Black population.

A Randomized, Double-Blind, Active Control Trial of Fluoroscopic Cervical Interlaminar Epidural Injections in Chronic Pain of Cervical Disc Herniation: Results of a 2-Year Follow-Up

Background: A recent evaluation of the state of U.S. health from 1990 to 2010 placed neck pain as the fourth condition leading to disability, with low back pain being the number one. Multiple treatment modalities have been described in managing neck and upper extremity pain secondary to cervical disc herniation after the failure of conservative management. The treatment modalities for chronic persistent pain of cervical disc herniation include surgery and epidural injections. The growth of interventional techniques in managing chronic spinal pain in recent years has been enormous. Evidence for the efficacy of cervical interlaminar epidural injections, however, continues to be debated, despite positive evidence derived from controlled randomized trials and systematic reviews. Study Design: A randomized, double-blind, active control trial. Setting: A private, specialty referral, interventional pain management practice in the United States. Objectives: To evaluate the effectiveness of epidural injections in managing chronic pain related to cervical disc herniation. Methods: Patients were randomly assigned to one of 2 groups of 60, with a total of 120 patients. Group I patients received cervical epidural injections with lidocaine 0.5% preservative-free, 5 mL, whereas Group II patients received 0.5% preservative-free lidocaine mixed with 1 mL or 6 mg of non-particulate betamethasone. Outcome Assessment: Multiple outcome measures included the numeric rating pain scale (NRS), the Neck Disability Index (NDI), employment status, opioid intake with assessment at 3, 6, 12, 18, and 24 months post treatment. Significant improvement was described as pain relief with a 50% improvement in functional status. Results: This evaluation showed significant improvement as 50% pain relief and improvement in functional status in 72% of the patients at 2 year follow-up in the local anesthetic group and 68% in those patients receiving local anesthetic and steroid. In the successful group of participants however, significant improvement was seen in 77% in Group I and 80% in Group II. Overall, the average number of procedures was 5 to 6 in both groups per 2 years. The average total relief for 2 years was 75.9 ± 29.9 weeks in Group I and 72.7 ± 31.1 in Group II, the successful group of participants. Taking into consideration all of the participants, the average total relief for 2 years was 69.6 ± 35 weeks in Group I and 62.1 ± 38.4 weeks in Group II. Limitations: The results of the study are limited by the lack of a placebo group. Conclusion: Cervical epidural injections with local anesthetic with or without steroids may offer significant benefit to patients suffering with chronic, persistent pain and disability related to cervical disc herniation. Key words: Chronic neck pain, cervical disc herniation, upper extremity pain, cervical epidural injections, epidural steroids, local anesthetics Trial Registration: NCT01071369

Comparison of esmolol and lidocaine for attenuation of cardiovascular stress response to laryngoscopy and endotracheal intubation in a Ghanaian population.

Background:Direct laryngoscopy and endotracheal intubation always trigger powerful cardiovascular responses. Various attempts have been made to attenuate these responses. The aim of this study was to compare the efficacy and safety of esmolol and lidocaine for suppressing cardiovascular response to laryngoscopy and tracheal intubation in a normotensive African population.Materials and Methods:A randomized controlled trial was conducted in 120 adult patients of American Society of Anaesthesiologists (ASA) physical status I or II undergoing various elective surgeries. The patients were randomly divided into three groups of 40 patients in each group - C, L, and E. Group - “C” received no drug (control) as placebo, group -“L” received 1.5 mg kg-1 preservative free lidocaine and group -“E” received 2 mg kg-1 esmolol IV 2 min before intubation. Mean arterial pressure (MAP) and rate-pressure product (RPP) were measured before induction as baseline and after tracheal intubation at minute 1, 3, and 5. The patients were randomly allocated to receive either saline (Group C), lidocaine 1.5 mg/kg (Group L), or esmolol 2 mg/kg (Group E) (n = 40, each group). After induction of general anesthesia with thiopental 6 mg/kg and vecuronium 0.12 mg/kg, the test solution was infused 2 min before tracheal intubation. Changes in heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial blood pressure (MAP), and rate-pressure product (RPP) were measured before induction of general anesthesia (baseline), 1, 3, and 5 min after tracheal intubation. Patients were also observed for any complications.Results:There was a significant increase in HR, SBP, DBP, MAP, and RPP from the base line in control group “C” at 1 min with onward decreases at 3 and 5 min respectively after intubation. Percentage change in hemodynamic variables in groups C, L, and E at 1 min are as follows: HR = 30.45, 26.00, and 1.50%; MAP = 20.80, 15.89, and 10.20%; RPP = 61.44, 40.86, and 11.68%, respectively. Only patients receiving placebo had increased HR, MAP, and RPP values after intubation compared with baseline values (P < 0.05).Conclusions:Prophylactic therapy with 2 mg kg-1 esmolol is more effective and safe for attenuating cardiovascular responses to laryngoscopy and tracheal intubation in a black population.

A Study of the Efficacy of Cardiac Antidysrhythmic Drugs in Attenuating Haemodynamic Responses to Laryngoscopy and Endotracheal Intubation in the Black Population

Background: Laryngeal, tracheal and bronchial receptors are stimulated by mechanical and chemical irritants during laryngoscopy and endotracheal intubation. That almost always triggers powerful cardiovascular responses. Various attempts have been made to attenuate these responses. The aim of this study was to compare the efficacy and safety of cardiac antidysrhythmic drugs lidocaine, diltiazem and esmolol in the attenuation of cardiovascular responses to endotracheal intubation in the Black normotensive population. Patients and Methods: A randomized controlled trial was conducted in 160 adult patients of ASA physical status I or II undergoing various elective surgeries. The patients were randomly divided into four groups of 40 patients in each group - C, L, D, and E. Group - “C” received no drug (control) as placebo, group -“L” received 1.5 mg kg-1 preservative free lidocaine, group -“D” received 0.2 mg kg-1 diltiazem, and group-“E” received 2mg kg-1 esmolol IV. Group “C”, “D” and “E”, “L” one and two minutes before intubation. Changes in Heart Rate (HR), Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP), and Mean Arterial Pressure (MAP) were measured and then compared within and between groups. Rate Pressure Product (RPP) was calculated and evaluated as well. Patients were also observed for any complications. Result: There was a significant increase in SBP, DBP, HR, MAP and RPP from the base line in control group “C” at 1 minute with onward decreases at 3 and 5 minutes respectively after intubation. Percentage change in haemodynamic variables in groups C, L, D and E at 1 minute are as follows: SBP=23.58%, 11.84%, 9.64% and 9.9%, DBP=18.73%, 18.89%, 11.93% and 10.40%, HR=30.45%, 26.00%, 7.01% and 1.50%, MAP=20.80%, 15.89%, 10.90 and 10.20%; RPP=61.44%, 40.86%, 17.26% and 11.68% respectively. Only patients receiving placebo had increased SBP, DBP, HR, MAP and RPP values after intubation compared with baseline values (p<0.05). Conclusions: Given the difference in the pharmacological mechanisms of these drugs, the prophylactic therapy with 2 mg kg-1 esmolol is significantly more effective and safe for attenuating haemodynamic changes to laryngoscopy and tracheal intubation, without producing increased risk of hypertension in the Black population.

Detection of nerve structures during peripheral nerve blockade in pigs model

Objective: In recent years regional anesthesia has gained great popularity. However, like any other medical procedure, the regional anesthesia carries certain risk of unintended intraneural injection and consequential neurological complications. Studies in animals have suggested that intraneural application of local anesthetics may cause mechanical injury. Previous studies, however, have used small animal models and clinically irrelevant injection speed or equipment. In this study we used equipment and injection methods in common clinical use to study the consequences and pressure dynamics of intraneural injection. Our hypothesis is that an intraneural injection is heralded by higher injection pressure and leads to neurologic impairment in pigs. Materials and Methods: Ten pigs of mixed breed (21-26 kg, 4-6 months old) were studied. After general anesthesia, the sciatic nerves (n = 20) were exposed bilaterally. Under direct vision, a 25-gauge insulated nerve block needle was placed either intraneurally (n = 10) or perineurally (n = 10), and 4 ml of preservative-free lidocaine 2% was injected using an automated infusion pump (15 ml/min). Injection pressure data were acquired using an in-line manometer coupled to a computer via an analog-to-digital conversion board. After injection, the animals were awakened and subjected to serial neurologic examinations during next 7 days. Results: All perineural injections resulted in injection pressures below 40 kPa. In contrast, intraneural injections resulted in significantly higher peak pressures (P 140 k Pa. Conclusion: High injection pressure (>140 kPa) predicts intraneural injection and consequential neurologic deficit. As long as the injection pressure is low, injection into poorly compliant tissue can be avoided and neurological complication can be prevented.

Assessment of effectiveness of percutaneous adhesiolysis in managing chronic low back pain secondary to lumbar central spinal canal stenosis.

Background: Chronic persistent low back and lower extremity pain secondary to central spinal stenosis is common and disabling. Lumbar surgical interventions with decompression or fusion are most commonly performed to manage severe spinal stenosis. However, epidural injections are also frequently performed in managing central spinal stenosis. After failure of epidural steroid injections, the next sequential step is percutaneous adhesiolysis and hypertonic saline neurolysis with a targeted delivery. The literature on the effectiveness of percutaneous adhesiolysis in managing central spinal stenosis after failure of epidural injections has not been widely studied.Study Design: A prospective evaluation.Setting: An interventional pain management practice, a specialty referral center, a private practice setting in the United States.Objective: To evaluate the effectiveness of percutaneous epidural adhesiolysis in patients with chronic low back and lower extremity pain with lumbar central spinal stenosis.Methods: Seventy patients were recruited. The initial phase of the study was randomized, double-blind with a comparison of percutaneous adhesiolysis with caudal epidural injections. The 25 patients from the adhesiolysis group continued with follow-up, along with 45 additional patients, leading to a total of 70 patients. All patients received percutaneous adhesiolysis and appropriate placement of the Racz catheter, followed by an injection of 5 mL of 2% preservative-free lidocaine with subsequent monitoring in the recovery room. In the recovery room, each patient also received 6 mL of 10% hypertonic sodium chloride solution, and 6 mg of non-particulate betamethasone, followed by an injection of 1 mL of sodium chloride solution and removal of the catheter.Outcomes Assessment: Multiple outcome measures were utilized including the Numeric Rating Scale (NRS), the Oswestry Disability Index 2.0 (ODI), employment status, and opioid intake with assessment at 3, 6, and 12, 18 and 24 months post treatment. The primary outcome measure was 50% or more improvement in pain scores and ODI scores.Results: Overall, a primary outcome or significant pain relief and functional status improvement of 50% or more was seen in 71% of patients at the end of 2 years. The overall number of procedures over a period of 2 years were 5.7 ± 2.73.Limitations: The lack of a control group and a prospective design.Conclusions: Significant relief and functional status improvement as seen in 71% of the 70 patients with percutaneous adhesiolysis utilizing local anesthetic steroids and hypertonic sodium chloride solution may be an effective management strategy in patients with chronic function limiting low back and lower extremity pain with central spinal stenosis after failure of conservatie management and fluoroscopically directed epidural injections.