Pharmacokinetics and metabolism of lidocaine HCl 2% with epinephrine in horses following a palmar digital nerve block.

BACKGROUND: Lidocaine is a local anesthetic that is sometimes administered in combination with epinephrine. The addition of epinephrine increases the time lidocaine remains at the site of administration, thus prolonging the duration of effect. Due to their potential to prevent the visual detection of lameness, the administration of local anesthetics is strictly regulated in performance and racehorses. Recent reports of positive regulatory findings for lidocaine in racehorses suggests a better understanding of the behavior of this drug is warranted. The objective of the current study was to describe serum and urine concentrations and the pharmacokinetics of lidocaine and its primary metabolites following administration in combination with epinephrine, as a palmar digital nerve block in horses. Twelve horses received a single administration of 1 mL of 2% lidocaine HCl (20 mg/horse) with epinephrine 1:100,000, over the palmar digital nerve. Blood samples were collected up to 30 h and urine samples up to 48 h post administration. Lidocaine and metabolite concentrations were determined by liquid chromatography- mass spectrometry and pharmacokinetic (non-compartmental and compartmental) analysis was performed. RESULTS: Serum concentrations of lidocaine and 3-hydroxylidocaine were above the LOQ of the assay at 30 h post administration and monoethylglycinexylidide (MEGX) and glycinexylidide (GX) were below detectable levels by 24 and 48 h, respectively. In urine, lidocaine, MEGX and GX were all non-detectable by 48 h post administration while 3-hydroxylidocaine was above LOQ at 48 h post administration. The time of maximal concentration for lidocaine was 0.26 h (median) and the terminal half-life was 3.78 h (mean). The rate of absorption (Ka) was 1.92 1/h and the rate of elimination (Kel) was 2.21 1/h. CONCLUSIONS: Compared to previous reports, the terminal half-life and subsequent detection time observed following administration of lidocaine in combination with epinephrine is prolonged. This is likely due to a decrease in systemic uptake of lidocaine because of epinephrine induced vasoconstriction. Results of the current study suggest it is prudent to use an extended withdrawal time when administering local anesthetics in combination with epinephrine to performance horses.

WALANT-Epinephrine injection may lead to short term, reversible episodes of critical oxygen saturation in the fingertips.

INTRODUCTION: Although the WALANT technique's long-term safeness has been demonstrated in many studies, there are only few data investigating its short-term effects on tissue perfusion and oxygen levels. It was hypothesized that, temporarily, critical levels of tissue perfusion may occur. METHODS: Seventeen patients, who were scheduled for different procedures in WALANT technique, were injected with 5-7 ml of 1% Articain containing 1:200,000 epinephrine at the finger base. Capillary-venous oxygen saturation, hemoglobin volume in the capillaries, and relative blood flow in the fingertips were recorded once per second by white light spectrometry and laser Doppler flowmetry before, during and after injection for an average of 32 min. RESULTS: Clinically, no persistent tissue malperfusion was observed, and there were no postoperative complications. Capillary-venous oxygen saturation was reduced by ≥ 30% in seven patients. Critical levels of oxygen saturation were detected in four patients during 13 intervals, each lasting for 132.5 s on average. Oxygen saturation returned to noncritical values in all patients by the end of the observation period. Blood flow in the fingertips was reduced by more than 30% in nine patients, but no critical levels were observed, as with the hemoglobin. Three patients demonstrated a reactive increase in blood flow of more than 30% after injection. CONCLUSIONS: Injection of tumescent local anesthesia containing epinephrine into finger base may temporarily cause a substantial reduction in blood flow and lead to critical levels of oxygen saturation in the fingertips. However, this was fully reversible within minutes and does not cause long-term complications.

Intranasal ketamine reduces pain of digital nerve block; a double blind randomized clinical trial.

BACKGROUND: Low dose ketamine can be used as analgesic in acute pain management in the emergency department (ED). OBJECTIVE: Efficacy of IN ketamine in acute pain management in the ED. METHOD: This is a double blind randomized clinical trial on patients older than 15 years who needed digital nerve block (DNB). Participants randomly received IN Ketamine (1 ml = 50 mg) or placebo (normal saline, 1 ml) 5 min before DNB. In both groups, patients' pain score was recorded by visual analogue score (VAS) at baseline, after DNB and 45 min after completion of DNB. Adverse effects of ketamine and changes in vital signs were also recorded and compared with placebo group. RESULTS: A total number of 100 patients were enrolled in the study with the median (IQR) age of 36.5 (26) years, including 65 men and 35 women. IN ketamine resulted in less pain compared to placebo after performing DNB and 45 min after the procedure. Median (IQR) basic VAS score was 50 (15) in ketamine group, and 49 (27) in control group. Median (IQR) block pain VAS score was 28.5 (19) in ketamine group and 47.5 (31) in control group. Median (IQR) procedural pain VAS score was 21.5 (16) in ketamine group and 43.5 (29) in control group. Only 7 patients had adverse effects in either group. CONCLUSION: The findings of this study suggest that IN ketamine can be effective in reducing pain in patients with acute pain, without adding significant side effects.

Onset Time of Local Anesthesia After Single Injection in Toe Nerve Blocks: A Randomized Double-Blind Trial.

PURPOSE: The study was conducted to investigate the onset time and safety profile of four different local anesthetic solutions. DESIGN: Randomized controlled clinical trial study. METHODS: One hundred twelve healthy volunteers were assigned to receive digital block on their second toe. Individuals were randomly assigned to one of the following groups: lidocaine 2%, lidocaine 2% with epinephrine, bupivacaine 0.5%, or bupivacaine 0.5% with epinephrine. Onset time was measured until detecting the absence of pinprick sensation. Oxygen saturation was measured in the infiltrated toe up to 60 minutes. FINDINGS: The subjects in the groups of anesthetics with epinephrine had a significantly lower mean onset time. There were no significant differences regarding oxygen saturation between the groups and no adverse effects were recorded. CONCLUSIONS: The use of anesthetics with epinephrine can be an effective form of local anesthetic for digital blocks when a rapid onset of action, prolonged duration of anesthesia, and vasoconstrictive action are required.

Comparison of pain and extent of anesthesia in digital blocks for isolated finger lacerations: A randomized controlled trial.

OBJECTIVES: Digital injuries are among the most common presentations to the emergency department. In order to sufficiently examine and manage these injuries, adequate, prompt, and predictable anesthesia is essential. In this trial, we aim to primarily compare the degree of pain and anesthesia onset time between the two-injection dorsal block technique (TD) and the single-injection volar subcutaneous block (SV) technique. Further, we describe the temporal and anatomical effects of both techniques for an accurate delineation of the anesthetized regions. METHODS: This is a single-center prospective randomized controlled trial involving patients presenting with isolated wounds to the fingers requiring primary repair under local anesthesia. Patients were randomized to either the SV or TD blocks. The primary outcome was procedure-related pain (Numerical Rating Scale). Further, we assessed the extent of anesthesia along with the anesthesia onset time. RESULTS: A total of 100 patients were included in the final analysis, 50 on each arm of the study. The median pain score during injection was significantly higher in patients who received TD block than patients who received SV block (median [interquartile range] = 4 [2.25, 5.00] vs. 3.00 [2.00, 4.00], respectively, P = 0.006). However, anesthesia onset time was not statistically different among the groups (P = 0.39). The extent of anesthesia was more predictable in the dorsal block compared to the volar block. CONCLUSION: The single-injection volar subcutaneous blocks are less painful with a similar anesthesia onset time. Injuries presenting in the proximal dorsal region may benefit from the two-injection dorsal blocks, given the anatomical differences and timely anesthesia of the region.

Reduction in pain from corticosteroid injection for the treatment of trigger finger with subcutaneous single-injection digital block: a randomized controlled trial.

PURPOSE: The pain from corticosteroid injections is not an insignificant issue for patients with trigger finger. The aim of this study was to evaluate the efficacy of subcutaneous single-injection digital block (SSIDB) for pain reduction during trigger finger corticosteroid injection. METHODS: Ninety patients requiring corticosteroid injections for trigger finger were randomized to three groups: SSIDB with 2 ml of 1% lidocaine, SSIDB with 1 ml of 1% lidocaine and no digital block (control group). In SSIDB groups, the intrasynovial corticosteroid injections were performed after digital nerve block. In control group, ethyl chloride spray was applied prior to intrasynovial injection of the corticosteroid and 1% lidocaine mixture. The pain during lidocaine needle insertion, lidocaine infiltration, corticosteroid needle insertion and corticosteroid infiltration were determined with a visual analog scale (VAS). RESULTS: The VAS pain scores for corticosteroid needle insertion in both SSIDB groups were significantly lower than the VAS pain scores in control group (p < 0.001). The VAS pain score during corticosteroid infiltration in 2 ml of 1% lidocaine group was significantly lower than 1 ml of 1% lidocaine group (p = 0.008), and in control group (p < 0.001). Pain during nerve block procedure in both SSIDB groups was significantly lower than the pain from corticosteroid injection in the control group (p < 0.05 and p < 0.05). CONCLUSIONS: Subcutaneous single-injection digital block with 2 ml of 1% lidocaine was highly effective in reducing pain associated with injection of corticosteroid for trigger finger.

Duration of skin desensitisation following palmar digital nerve blocks with lidocaine, bupivacaine, mepivacaine and prilocaine.

Objective comparative evidence of the time to onset and duration of effect provided by local anaesthetic (LA) agents for perineural blocks in the horse is lacking. Clear knowledge of these properties is required to guide clinically appropriate agent selection and aid interpretation of response to diagnostic blocks for lameness examinations. An interventional study, with complete, randomised crossover design was used to compare time to onset and duration of skin desensitisation provided by four LA agents applied to palmar digital nerve blocks in 12 horses. Effect at each time point was determined using a pressure gauge to measure the mechanical nociceptive threshold (MNT) over the heel bulbs. Complete desensitisation was defined when MNT was greater than four times the pre-block baseline. Onset and duration of complete desensitisation were recorded and compared across agents using a mixed linear model. When significant (P ≤ 0.05), post-hoc paired comparisons between agents were performed against a Tukey's corrected P ≤ 0.05. Onset of complete skin desensitisation for each agent was <5 min. Duration for lidocaine (mean 25 min; 95% confidence interval [CI] 9-42) was shorter than bupivacaine (53 min; 95% CI 39-65), which was shorter than both prilocaine (102 min; 95% CI 81-123) and mepivacaine (107 min; 95% CI 92-121), which were not different. Although onset of complete skin desensitisation was not different for the LA agents tested, duration varied from 25 min to nearly 2 h. Prilocaine and mepivacaine provided the most prolonged duration of effect, both exceeding bupivacaine.

Effect of Perineural Anesthesia on the Centre of Pressure (COP) Path During Stance Phase at Trot in Sound Horses.

This study aimed to examine how short-term loss of proprioception in the equine foot influences the individual COP path during the stance phase of the trot in sound horses. Ten horses were evaluated to be objectively non-lame using the 'Equinosis Q System and subsequently examined using a portable pressure measuring system with pressure foils fixed directly underneath both front hooves prior to and after perineural anesthesia of the palmar digital nerves. The individual COP paths of both forelimbs was assessed prior to and after unilateral and bilateral abaxial sesamoid nerve blocks. COP from initial contact to mid stance and breakover as well as the inter-stride variability were descriptively evaluated for each horse and limb. The individual COP path for each horse and limb during stance was shown to be highly repeatable without significant inter-stride variability. Location of initial contact, COP during midstance and breakover are not affected by unilateral or bilateral short-term loss of sensory feedback from the foot after perineural anesthesia. Anesthesia of the foot with an abaxial sesamoid nerve block does not affect the foot's COP during stance at a trot, therefore, sudden changes in gait pattern after perineural anesthesia should be interpreted with caution and warrant further clinical investigation.

Regional anaesthesia on the finger: Traditional dorsal digital nerve block versus subcutaneous volar nerve block, a randomized controlled trial.

OBJECTIVE: To identify the most comfortable digital nerve block by comparing painfulness and efficiency of two commonly used digital nerve blocks: the volar subcutaneous nerve block and the traditional dorsal nerve block. METHODS: Patients, age ≥ 18 years, presenting with an injury of the finger requiring regional anaesthesia were included. Patients were blindly randomized in receiving the one-injection subcutaneous volar nerve block (intervention group) or the two-injection traditional dorsal digital nerve block (control group). Primary outcome measure was discomfort of the injection. Secondary outcome measures were extent of anaesthesia in different regions of the finger, complication rate and satisfaction of the clinician. RESULTS: In total, 409 patients were randomly allocated to the intervention group (N=209) or control group (N=200). Discomfort of the injection was not different between both anaesthetic techniques. The mean pain score (Numerical Rating Scale - NRS) of the intervention group was 4.57 (range 0 - 9, CI 4.27 - 4.87, SD 2.18). The mean pain scores of the control group were 4.63 for the first injection (range 0 - 10; CI 4.28 - 4.99, SD 2.36) and 4.51 for the second injection (range 0 - 10; CI 4.14 - 4.87, SD 2.44). The traditional dorsal digital nerve block was better in anesthetizing the dorsal side of the finger. The subcutaneous volar nerve block was better or equivalent in terms of extent of anaesthesia on the volar side of the finger. CONCLUSION: In patients requiring digital anaesthesia in the Emergency Department, the anaesthetic technique affects both the discomfort of the injection and extent of anaesthesia. The traditional dorsal digital nerve block is preferred for dorsal injuries. The subcutaneous volar nerve block is preferred for volar injuries.

Effect on analgesia duration and pain intensity of adding dexamethasone to lidocaine in digital nerve block in patients with finger trauma.

Digital nerve block is one of the multimodal analgesia methods used in finger trauma cases. According to some studies, dexamethasone needs further investigation before being used routinely. We therefore investigated dexamethasone's effect on the parameters of digital nerve block. In this double-blind clinical study, 60 patients were allocated to two groups: lidocaine alone and lidocaine + dexamethasone. Groups were compared for pain intensity, analgesia duration and demographic characteristics. Patients in the intervention group received 3 cc 2% lidocaine + 1 cc (equivalent to 4 mg) dexamethasone and patients in the control group received 3 cc lidocaine 2% + 1 cc normal saline. The two groups were comparable for age and gender. In the lidocaine + dexamethasone group, postoperative pain severity was significantly lower and the pain-free period was longer (P < 0.05). Dexamethasone as an adjuvant in digital nerve block after trauma reduced the severity of postoperative pain and increased the pain-free period.

The assessment of ice pack effect in pain reduction during digital nerve block: A randomized clinical study.

OBJECTIVES: Digital nerve block is a painful procedure. Several methods have been proposed to decrease the injection pain. Applying an ice pack is a pertinent choice due to its effectiveness on pain reduction, convenience, and low costs. In this study, the degree of injection pain reduction was assessed after applying an ice pack to the site of anesthetic injection. METHODS: One hundred participants with traumatic finger injury were assessed. Digital nerve block was performed in fifty patients in the intervention group after 6 min of ice application. In the control group, this procedure was done without ice. The primary outcome was the difference between the needle stick and infiltration pain scores with and without ice pack. The secondary outcome the patient satisfaction score. The protocol of this study was approved by the Institutional Review Board, and it is registered in the Iranian Registry of Clinical Trials. RESULTS: The pain score was assessed using a Numeric Rating Scale. Both the needle skin and infiltration pain scores were statistically significantly lower in the intervention group (P < 0.001). The mean and median needle stick pain scores were 1.5 and 1.0 in the intervention group and 6.8 and 7.0 in the control group, respectively. Moreover, the mean and median infiltration pain scores were 2.7 and 2.0 in the intervention group and 8.5 and 9.0 in the control group, respectively. Patient satisfaction score was significantly higher in the intervention group. CONCLUSIONS: Ice pack is inexpensive, readily available, and is easy to apply. We recommend this method to reduce the injection pain before digital nerve block in the emergency department.

Pigmented border as a new surface landmark for digital nerve blocks: a cross sectional anatomical study.

The purpose of this study was to identify surface anatomy of digital nerves in relation to the pigmented border of digits. Three-hundred and sixty digital nerves in 36 preserved adult cadaveric hands were dissected under magnification. The digital nerves were constantly located anterior to the pigmented border. The median curvilinear distance along the skin from the pigmented border to the digital nerves of the index, middle, ring and little fingers was 1.4 mm. In the thumb, this distance was 2.4 and 3.7 mm on the radial and ulnar sides, respectively. The digital nerve was located 2.4 mm deep to the skin in all fingers. The median angle to the nerve from the skin at the pigmented border was 30°. These dimensions differed in the thumb compared with the rest of the fingers. We conclude that the pigmented border of digits is a reliable anatomical landmark to locate digital nerves.

Two injection digital block versus single subcutaneous palmar injection block for finger lacerations.

PURPOSE: We aimed to compare two digital nerve block techniques in patients due to traumatic digital lacerations. METHODS: This was a randomized-controlled study designed prospectively in the emergency department of a university-based training and research hospital. Randomization was achieved by sealed envelopes. Half of the patients were randomised to traditional (two-injection) digital nerve block technique while single-injection digital nerve block technique was applied to the other half. Score of pain due to anesthetic infiltration and suturing, onset time of total anesthesia, need for an additional rescue injection were the parameters evaluated with both groups. Epinephrin added lidocaine hydrochloride preparation was used for the anesthetic application. Visual analog scale was used for the evaluation of pain scores. Outcomes were compared by using Mann-Whitney U test and Student t-test. RESULTS: Fifty emergency department patients ≥18 years requiring digital nerve block were enrolled in the study. Mean age of the patients was 33 (min-max: 19-86) and 39 (78 %) were male. No statistically significant difference was found between the two groups in terms of our main parameters; anesthesia pain score, suturing pain score, onset time of total anesthesia and rescue injection need. CONCLUSION: Single injection volar digital nerve block technique is a suitable alternative for digital anesthesias in emergency departments.

The Influence of Injected Volume on Discomfort During Administration of Digital Block.

BACKGROUND: Digital nerve block is associated with pain. In a search for methods to reduce the discomfort, we investigated how the volume of anaesthetic fluid influences pain during subcutaneous digital nerve block, and how it affects the success of the anaesthesia. METHODS: A randomized blinded prospective study was performed on 36 healthy volunteers. The single injection subcutaneous digital block technique was used to anaesthetize the participants´ 4th digit on both hands. The same amount of lidocaine was used, but in two different volumes; 1 ml 2% lidocaine and 2ml 1% lidocaine. After each injection the participant was asked to estimate pain intensity on a visual analogue scale (VAS). The distribution of anaesthesia was then measured by using a Semmes-Weinstein 4.56 monofilament. Finally, participants gave a verbal assessment of which injection was least painful. RESULTS: In total, 72 blocks were performed. There were no statistically significant differences in pain intensity or preference between the two groups. Furthermore, the 1 ml injection gave poorer anaesthesia and had longer time to onset. Neither injection anaesthetized the dorsal aspect of the proximal phalanx. CONCLUSIONS: The two volumes cause the same degree of discomfort. Greater volume gives a greater area of distribution and more rapid onset of anaesthesia. It seems unreasonable to use a smaller volume of more concentrated anaesthetic when performing the subcutaneous technique.

Skin perfusion and pain evaluation with different local anaesthetics in a double blind randomized study following digital nerve block anaesthesia.

OBJECTIVE: Supplementing a local anaesthetic with epinephrine has advantages in hand surgery: faster onset of anaesthesia, extended effect of anaesthetics with prolonged pain reduction, decreased bleeding into the operative field, and abandoned need for tourniquet. We hypothesized that the use of ropivacaine with epinephrine additive in digits allows good skin perfusion rates with prolonged pain reduction. DESIGN: In this prospective, double-blinded, randomized study with 20 volunteers (80 fingers, without operation) the chronological course of changes in digit blood flow, post injection pain status and complication rates after two-injection dorsal technique anaesthetic block with ropivacaine (group 1: ropivacaine 0.75%, group 2: ropivacaine 0.75% and epinephrine 1 : 1.000.000, group 3: local tumescent anaesthesia 0.15% TLA: ropivacaine, lidocaine, saline solution plus epinephrine 1 : 1.000.000) were examined. As a control group, injection of 2% lidocaine in the way with 20 minutes tourniquet (group 4) was used. MAIN OUTCOME: Group 1 showed increased skin perfusion with a maximum of 160.2%, group 2 showed no significant changes with a following significant increase of skin perfusion (+66.6%). In group 3, a significant reduction (-54.1%) was followed by an increase of skin perfusion (+45.7%). In the control group (group 4) the skin perfusion was decreased (-66.2%) and increased significantly after opening the tourniquet (+248.1%). The longest pain reduction was shown for ropivacaine 0.75% and epinephrine with 18.0 hours (group 2); the other groups were between 4.6 to 8.1 hours. CONCLUSION: Using ropivacaine with epinephrine additive in digits could improve the intra-, and postoperative terms.

Response of three digital anesthetic technics in horses with forelimb hoof lameness / Resposta de três técnicas anestésicas digitais em equinos com claudicação dos membros anteriores ligada ao casco

The presented study aimed to assess objectively the response of distal interphalangeal joint (DIJ), navicular bursa (NB) and deep digital flexor tendon sheath (DDFTS) anesthesia in horses with forelimb hoof lameness; and evaluate if the presence of radiographic abnormalities on navicular bone could interfere on blocks' results. Fifteen horses with lameness improvement above 70% after palmar digital nerve (PDN) block were selected for this study. Blocks were assessed separately on five consecutive trials at seven different time-points. The fifth trial was performed to evaluate the influence of exercise on preexisting lameness. Most of horses (73.33%) presented pain related to the podotrochlear apparatus based on clinical and lameness exam and blocks' responses. NB and DIJ anesthesia differed on the frequency of horses with lameness improvement above 70% only at 10min (p=0.03), and both differed from DDFTS block until 30'(p<0.05). The blocks' response was variable along the time and the highest means for NB, DIJ and DDFTS were observed at 5-10 minutes ('), 15-20' and 10-15' respectively.Exercise had low interference on lameness intensity since no improvement above 50% was observed and an increase on lameness intensity over time was identified in seven horses. Variable grades of navicular bone radiographic lesions were observed in 14 horses, although these lesions had no interference on blocks' response (p>0.05). The NB and DIJ blocks had similar responses and both were superior to DDFTS anesthesia, coincident with a major prevalence of podotroclear apparatus abnormalities in this equine population.(AU)

O presente estudo avaliou, de forma objetiva, as respostas do bloqueio da articulação interfalangeana distal (AID), da bursa do navicular (BN) e da bainha do tendão flexor digital profundo (BTFDP) em equinos com claudicação ligada ao casco nos membros torácicos; além de analisar a influência das alterações radiográficas do osso navicular no resultado dos bloqueios. Quinze cavalos, que apresentaram uma melhora da claudicação acima de 70% após o bloqueio do nervo digital palmar, foram selecionados para este estudo. Os bloqueios foram avaliados separadamente em cinco turnos consecutivos e em sete tempos diferentes. O quinto turno foi utilizado para analisar a influência do exercício sobre a claudicação preexistente. A maioria dos cavalos (73,33%) apresentou dor relacionada à porção palmar do casco, com base nos achados do exame clínico em movimento e nas respostas dos bloqueios. As anestesias da BN e da AID apresentaram diferença quanto à frequência de cavalos com melhora da claudicação acima de 70% apenas aos 10min (p=0.03), e ambos diferiram do bloqueio da BTFDP até os 30min (p<0.05). A resposta dos bloqueios foi variada ao longo do tempo, e as maiores médias de melhora da claudicação para os bloqueios BN, AID e BTFDP foram observadas aos 5-10min, 15-20min e 10-15min, respectivamente. O exercício teve pequena interferência na intensidade da claudicação, uma vez que nenhuma melhora acima de 50% foi observada e sete cavalos aumentaram a intensidade da claudicação ao longo do tempo. A presença de diferentes graus de lesão radiográfica do osso navicular foi observada em 14 cavalos, porém essas lesões não interferiram na resposta dos bloqueios (p>0,05). Os bloqueios da BN e da AID apresentaram respostas semelhantes, e ambos foram superiores ao bloqueio da BTFDP, coincidindo com uma marcada prevalência de doença do aparato podotroclear nesta população de equinos.(AU)

Is it true that injecting palmar finger skin hurts more than dorsal skin? New level 1 evidence.

BACKGROUND: Since the first texts on local anesthesia were written in the early 1900s, it has been widely quoted and believed that dorsal finger skin is less sensitive to needlestick pain than volar finger skin. The result is that the most commonly used finger block for local anesthesia is the dorsal two injection technique. METHODS: In this study, the needlestick discomfort associated with dorsal and volar finger skin was compared in a group of 78 volunteers who had the long finger of both hands poked with a 25 G needle; one in the midline of the volar side and the other in the lateral web space of the dorsal side. Volunteers then completed a pain scale for each needlestick and ranked which technique they would prefer for future injections. RESULTS: We found that there was no significant difference in needlestick pain or preference of future needle location between the dorsal and volar aspects of the finger. CONCLUSIONS: We provide level 1 evidence that the needlestick of the SIMPLE block which has one needlestick on the volar side of the finger is not more painful than the needlestick of the dorsal finger block.