In 1970, Winnie proposed the brachial plexus block as an alternative and effective anaesthesia technique for shoulder surgery. From that date, several techniques have been developed to approach the brachial plexus: the use of a nerve stimulator and, more recently, the ultrasound guided nerve blockade have made the procedure easier and more effective; the availability of the new drugs demonstrates some major advantages due to the application of peripheral blocks. Nowadays the attention has been focused on postoperative pain control: although many techniques have been proposed, the application of a continuous infusion of local anaesthetics through an interscalene catheter seems the best available technique to achieve pain relief after shoulder surgery. Advantages ad disadvantages of regional anaesthesia and adverse events associated with interscalene brachial plexus blockade are reviewed.
Shoulder surgery; brachial plexus; interscalene block; postoperative analgesia
A continuous interscalene brachial plexus block is a highly effective postoperative analgesic modality after shoulder surgery. However, there is no consensus regarding the optimal basal infusion rate of ropivacaine for a continuous interscalene brachial plexus block. A prospective, double blind study was performed to compare two different basal rates of 0.2% ropivacaine for a continuous interscalene brachial plexus block after shoulder surgery.
Sixty-two patients receiving shoulder surgery under an interscalene brachial plexus block were included. The continuous interscalene brachial plexus block was performed using a modified lateral technique with 30 ml of 0.5% ropivacaine. Surgery was carried out under an interscalene brachial plexus block or general anesthesia. After surgery, the patients were divided randomly into two groups containing 32 each. During the first 48 h after surgery, groups R8 and R6 received a continuous infusion of 0.2% ropivacaine at 8 ml/h and 6 ml/h, respectively. The pain scores at rest and on movement, supplemental analgesia, motor block, adverse events and patient's satisfaction were recorded.
The pain scores, supplemental analgesia, motor block, adverse events and patient's satisfaction were similar in the two groups.
When providing continuous interscalene brachial plexus block after shoulder surgery, 0.2% ropivacaine at a basal rate of 8 ml/h or 6 ml/h produces similar clinical efficacy. Therefore, decreasing the basal rate of CISB is more appropriate considering the toxicity of local anesthetics.
Continuous interscalene block; Ropivacaine; Shoulder surgery
The article reviews the current literature regarding shoulder anesthesia and analgesia. Techniques and outcomes are presented that summarize our present understanding of regional anesthesia for the shoulder. Shoulder procedures producing mild to moderate pain may be managed with a single-injection interscalene block. However, studies support that moderate to severe pain, lasting for several days is best managed with a continuous interscalene block. This may cause increased extremity numbness, but will provide greater analgesia, reduce supplemental opioid consumption, improve sleep quality and patient satisfaction. In comparison to the nerve stimulation technique, ultrasound can reduce the volume of local anesthetic needed to produce an effective interscalene block. However, it has not been shown that ultrasound offers a definitive benefit in preventing major complications. The evidence indicates that the suprascapular and/or axillary nerve blocks are not as effective as an interscalene block. However in patients who are not candidates for the interscalene block, these blocks may provide a useful alternative for short-term pain relief. There is substantial evidence showing that subacromial and intra-articular injections provide little clinical benefit for postoperative analgesia. Given that these injections may be associated with irreversible chondrotoxicity, the injections are not presently recommended.
Interscalene brachial plexus block (ISBPB) is an effective technique for shoulder surgery and postoperative pain control. The aim of this study is to compare the analgesic efficacy of 0.1% vs 0.2% bupivacaine for continuous postoperative pain control following arthroscopic shoulder surgery.
A total of 40 adult patients divided into two groups (each 20 patients) undergoing arthroscopic shoulder surgery were randomized to receive an ultrasound-guided ISBPB of either 0.1% or 0.2% bupivacaine 10 ml bolus plus 5 ml/h infusion through interscalene catheter. Standard general anesthesia was given. Both groups received rescue postoperative PCA morphine. Pain, sensory, and motor power were assessed before for all patients, 20 minute after the block, postoperatively in the recovery room, and at 2, 6, 12, and 24 hours thereafter. The patient and surgeon satisfaction and the analgesic consumption of morphine were recorded in the first 24 hours postoperatively. A nonparametric Mann-Whitney was used to compare between the two groups for numerical rating scale, morphine consumption in different time interval.
Group 1 (0.1% bupivacaine) patients had significantly received more intraoperative fentanyl and postoperative morphine with higher pain scores at 24 hours postoperatively vs group 2 (0.2% bupivacaine) patients.
The use of ultrasound-guided ISBPB with 0.2% bupivacaine provided better intra- and post-operative pain relief vs 0.1% bupivacaine in arthroscopic shoulder surgery.
Interscalene block; pain; shoulder arthroscopy
Background and Objectives:
It is currently unknown if the primary determinant of continuous peripheral nerve block effects is simply total drug dose, or whether local anesthetic concentration and/or volume have an influence. We therefore tested the null hypothesis that providing ropivacaine at different concentrations and rates—but at an equal total basal dose—produces similar effects when used in a continuous interscalene nerve block.
Preoperatively, an interscalene perineural catheter was inserted using the anteriolateral approach in patients undergoing moderately painful shoulder surgery. Subjects were randomly assigned to receive a postoperative perineural infusion of either 0.2% ropivacaine (basal 8 mL/h, bolus 4 mL) or 0.4% ropivacaine (basal 4 mL/h, bolus 2 mL) through the second postoperative day. Our primary end point was the incidence of an insensate hand/finger during the 24-hours beginning the morning following surgery.
The incidence of an insensate hand/finger did not differ between the treatment groups (n=50) to a statistically significant degree (0.2% ropivacaine mean [SD] of 0.8 [1.3] times; 0.4% ropivacaine mean 0.3 [0.6] times; estimated difference=0.5 episodes, 95% confidence interval, −0.1 to 1.1 episodes; p=0.080). However, this is statistically inconclusive given the confidence interval. In contrast, pain (p=0.020) and dissatisfaction (p=0.011) were greater in patients given 0.4% ropivacaine.
For continuous interscalene nerve blocks, the 95% confidence interval (plausible differences in the incidence of an insensate hand/finger) contains values ranging from a clinically important disadvantage (1.1) to a clinically unimportant advantage (−0.1) for the lower concentration. Given the statistically inconclusive results and design limitations of the current study, further research on this issue is warranted. In contrast, providing a lower concentration of local anesthetic at a higher basal rate provided superior analgesia. These relationships are different than previously reported for continuous popliteal-sciatic nerve blocks. The interaction between local anesthetic concentration and volume is thus complex and varies among catheter locations.
anesthesia; continuous peripheral nerve block; continuous interscalene nerve block; patient-controlled regional analgesia; perineural local anesthetic infusion
Continuous interscalene block has been known to improve postoperative analgesia after arthroscopic shoulder surgery. This was a prospective study investigating the ultrasound-guided posterior approach for placement of an interscalene catheter, clinical efficacy and complications after placement of the catheter.
Forty-two patients undergoing elective arthroscopic shoulder surgery were included in this study and an interscalene catheter was inserted under the guidance of ultrasound with posterior approach. With the inplane approach, the 17 G Tuohy needle was advanced until the tip was placed between the C5 and C6 nerve roots. After a bolus injection of 20 ml of 0.2% ropivacaine, a catheter was threaded and secured. A continuous infusion of ropivacaine 0.2% 4 ml/hr with patient-controlled 5 ml boluses every hour was used over 2 days. Difficulties in placement of the catheter, clinical efficacy of analgesia and complications were recorded. All patients were monitored for 48 hours and examined by the surgeon for complications within 2 weeks of hospital discharge.
Easy placement of the catheter was achieved in 100% of the patients and the success rate of catheter placement during the 48 hr period was 92.9%. Postoperative analgesia was effective in 88.1% of the patients in the post anesthetic care unit. The major complications included nausea (7.1%), vomiting (4.8%), dyspnea (4.8%) and unintended vascular punctures (2.4%). Other complications such as neurologic deficits and local infection around the puncture site did not occur.
The ultrasound-guided interscalene block with a posterior approach is associated with a success high rate in placement of the interscalene catheter and a low rate of complications. However, the small sample size limits us to draw definite conclusions. Therefore, a well-designed randomized controlled trial is required to confirm our preliminary study.
Complication; Continuous interscalene block; Posterior approach; Ultrasound
An interscalene brachial plexus block is an effective means of providing anesthesia-analgesia for shoulder surgery. However, it has a multitude of potential side effects such as phrenic nerve block. We report a case of a patient who developed atelectasis of the lung, and pleural effusion manifested as chest discomfort during a continuous interscalene brachial plexus block for postoperative analgesia.
Atelectasis; Continuous interscalene brachial plexus block; Phrenic nerve; Pleural effusion
Background and the purpose of the study
Opioids are usually used in regional anesthesia, with or without local anesthetics to improve the regional block or postoperative pain control. Since no data are available on fentanyl's effect on the onset time of lidocaine interscalene anesthesia, the purpose of this study was to examine its effect on the onset time of sensory and motor blockade during interscalene anesthesia.
In a prospective, randomized, double-blind study, ninety patients scheduled for elective shoulder, arm and forearm surgeries under an interscalene brachial plexus block.They were randomly allocated to receive either 30 ml of 1.5% lidocaine with 1.5 ml of isotonic saline (control group, n=39) or 30 ml of 1.5% lidocaine with 1.5 ml (75 µg) of fentanyl (fentanyl group, n=41). Then the onset time of sensory and motor blockades of the shoulder, arm and forearm were evaluated every 60 sec. The onset time of the sensory and motor blockades was defined as the time between the last injection and the total abolition of the pinprick response and complete paralysis. The duration of sensory blocks were considered as the time interval between the administration of the local anesthetic and the first postoperative pain sensation.
Ten patients were excluded because of unsuccessful blockade or unbearable pain during the surgery. The onset time of the sensory block was significantly faster in the fentanyl group (186.54±62.71sec) compared with the control group (289.51±81.22, P<0.01). The onset times of the motor block up to complete paralysis in forearm flexion was significantly faster in the fentanyl group (260.61±119.91sec) than the control group (367.08±162.43sec, P<0.01). There was no difference in the duration of the sensory block between two groups.
Results of the study showed that the combination of 75 µg fentanyl and 1.5% lidocaine solution accelerated the onset of sensory and motor blockade during interscalene anesthesia.
Interscalene block; Regional anesthesia; Peripheral opioids effect
Purpose of review
To review the recently published peer-reviewed literature involving regional anesthesia and analgesia in patients at home.
The potential benefits and risks of regional anesthesia and analgesia at home are pertinent queries, and increased data regarding these topics are rapidly becoming available. Of particular interest is the use of continuous peripheral nerve blocks at home and their potential effect upon hospitalization duration and recovery profile.
Advantages of regional techniques include site-specific anesthesia and decreased postoperative opioid use. For shoulder surgeries, the interscalene block provides effective analgesia with minimal complications, whereas the impact and risks of intraarticular injections remain unclear. Perineural catheters are an analgesic option that offer improved pain relief among other benefits. They are now being used at home in both adult and pediatric populations.
ambulatory continuous peripheral nerve blocks; ambulatory patient-controlled regional analgesia; ambulatory perineural local anesthetic infusion; ambulatory surgery; regional analgesia at home
The posterior approach for placing continuous interscalene catheters has not been studied in a controlled investigation. In this randomized, triple-masked, placebo-controlled study, we tested the hypothesis that an ultrasound-guided continuous posterior interscalene block provides superior postoperative analgesia compared to a single-injection ropivacaine interscalene block after moderately painful shoulder surgery.
Preoperatively, subjects received a stimulating interscalene catheter using an ultrasound-guided, in-plane posterior approach. All subjects received an initial bolus of ropivacaine. Postoperatively, subjects were discharged with oral analgesics and a portable infusion device containing either ropivacaine 0.2% or normal saline programmed to deliver a perineural infusion over 2 days. The primary outcome was average pain on postoperative day (POD) 1 (scale: 0–10). Secondary outcomes included least and worst pain scores, oral opioid requirements, sleep disturbances, patient satisfaction, and incidence of complications.
Of the 32 subjects enrolled, 30 perineural catheters were placed per protocol. Continuous ropivacaine perineural infusion (n = 15) produced a statistically and clinically significant reduction in average pain (median [10th–90th percentile]) on POD 1 compared with saline infusion (n = 15) after initial ropivacaine bolus (0.0 [0.0–5.0] versus 3.0 [0.0–6.0], respectively; P < 0.001). Median oral opioid consumption (oxycodone) was lower in the ropivacaine group than in the placebo group on POD 1 (P = 0.002) and POD 2 (P = 0.002). Subjects who received a ropivacaine infusion suffered fewer sleep disturbances than those in the placebo group (P = 0.005 on POD 0 and 1 nights) and rated their satisfaction with analgesia higher than subjects who received normal saline (P < 0.001).
Compared to a single-injection interscalene block, a 2-day continuous posterior interscalene block provides greater pain relief, minimizes supplemental opioid requirements, greatly improves sleep quality, and increases patient satisfaction after moderate-to-severe painful outpatient shoulder surgery.
Recent investigations of local anesthetic distribution in the lower extremity have revealed that completely surrounding the sciatic nerve with local anesthetic provides the advantage of more rapid and complete anesthesia in the territory served by the nerve. We hypothesized that a pattern of distribution which entirely envelops the targeted nerve roots during interscalene block would provide similar benefits of more rapid anesthesia onset.
During interscalene block guided by ultrasound with nerve-stimulator confirmation, the pattern of local anesthetic distribution was recorded and later classified as complete or incomplete envelopment of the visible nerve elements in 50 patients undergoing ambulatory shoulder arthroscopic surgery. The pattern was then compared to the extent of block set-up at predetermined intervals, as well as to postoperative pain levels and block duration.
22 patients (44%) had complete envelopment of the nerves in the plane of injection during ultrasound imaging of the interscalene block. There was no difference in the fraction of blocks that were fully set-up at 10 minutes with regards to complete or incomplete envelopment of the nerves by local anesthetic. All of the patients had complete set-up of the block by 20 minutes. In addition, the postoperative pain levels and duration of block did not vary among the two groups with complete versus incomplete local anesthetic distribution around the nerves.
The presence or absence of complete envelopment of the nerve elements in the interscalene groove by local anesthetic did not determine the likelihood of complete block effect at predetermined time intervals after the procedure.
The purpose of this study was to evaluate the effect of the addition of 5 mg dexamethasone to 10 ml of 0.5% levobupivacaine on postoperative analgesic effects of ultrasound guided-interscalene brachial plexus block (ISBPB) in arthroscopic shoulder surgery under general anesthesia.
In 60 patients scheduled for arthroscopic shoulder surgery that underwent general anesthesia, ISBPB was preoperatively performed with 10 ml of 0.5% levobupivacaine under the guidance of ultrasound and a nerve stimulator. Patients were randomly allocated to receive the same volume of normal saline (Group I), 5 mg of dexamethasone (Group II), or 1 : 400,000 epinephrine (Group III) as an adjuvant to the mixture. A blind observer recorded total analgesic consumption, sleep quality, complication, and patient satisfaction using a verbal numerical rating scale (VNRS) at 0, 1, 6, 12, 24, 48 h after the operation.
All patients had successful ISBPB and excellent analgesic effects less than VNRS 4 up to discharge time. VNRS in Group II at 12 h and 48 h was statistically much lower than in Group I and III. There were no differences in total analgesic consumption, sleep quality, complications, and patient satisfaction.
We conclude that the addition of 5 mg of dexamethasone to 10 ml of 0.5% levobupivacaine in ISBPB showed improvement of postoperative analgesia for arthroscopic shoulder operation without any specific complications.
Analgesia; Brachial plexus blocks; Dexamethasone; Levobupivacaine; Ultrasound
The ability to provide adequate intraoperative anesthesia and postoperative analgesia for orthopedic shoulder surgery continues to be a procedural challenge. Anesthesiology training programs constantly balance the time needed for procedural education versus associated costs. The administration of brachial plexus anesthesia can be facilitated through nerve stimulation or by ultrasound guidance. The benefits of using a nerve stimulator include a high incidence of success and less cost when compared to ultrasonography. Recent studies with ultrasonography suggest high success rates and decreased procedural times, but less is known about the comparison of these procedural times in training programs. We conducted a prospective, randomized, observer-blinded study with inexperienced clinical anesthesia (CA) residents—CA-1 to CA-3—to compare differences in these 2 guidance techniques in patients undergoing interscalene brachial plexus block for orthopedic surgery.
In this study, 41 patients scheduled for orthopedic shoulder surgery were randomly assigned to receive an interscalene brachial plexus block guided by either ultrasound (US group) or nerve stimulation (NS group). Preoperative analgesics and sedatives were controlled in both groups.
The US group required significantly less time to conduct the block (4.3 ± 1.5 minutes) than the NS group (10 ± 1.5 minutes), P = .009. Moreover, the US group achieved a significantly faster onset of sensory block (US group, 12 ± 2 minutes; NS group, 19 ± 2 minutes; P = .02) and motor block (US group, 13.5 ± 2.3 minutes; NS group, 20.2 ± 2.1 minutes; P = .03). Success rates were high for both techniques and were not statistically different (US group, 95%; NS group, 91%). No differences were found in operative times, postoperative pain scores, need for rescue analgesics, or incidences of perioperative or postdischarge side effects.
On the basis of our results with inexperienced residents, we found that using US in guiding the interscalene approach to the brachial plexus significantly shortened the duration of intervals in conduction of the block and onset of anesthesia when compared with NS; moreover, these times could have significant cost savings for the institution. Finally, the use of US technology in an academic medical center facilitates safe, cost-effective, quality care.
Interscalene brachial plexus block; mepivacaine; nerve stimulator equipment; regional anesthetic technique; ropivacaine; ultrasound equipment
The occurrence of severe hypotension and bradycardia, following placing to the beach chair position from supine during general anesthesia for repair of tendon injury of the rotator cuff of shoulder in a healthy 50 year-old man was described. The Bezold-Jarisch reflex, which is known to inhibit cardiovascular reflex and composed of three kinds of symptoms such as vasodilation, bradycardia and hypotension, has been reported mainly in peripheral nerve block, and may occur during orthostasis, hypovolemia, hemorrhage, supine inferior vena cava compression in pregnancy, interscalene block for shoulder surgery in the sitting position and so on. The bradycardia and hypotension can be more aggravated when causative elements overlaps each other. Anticholinergics and vasopressor were injected intravenously, and position of the patient was changed to the supine position immediately resulting in a normal vital signs dramatically.
Bradycardia; General anesthesia; Position; Reflex
Ultrasound-guided peripheral nerve blocks facilitate ambulatory anesthesia for upper limb surgeries. Unilateral phrenic nerve blockade is a common complication after interscalene brachial plexus block, rather than the supraclavicular block. We report a case of severe respiratory distress and bilateral bronchospasm following ultrasound-guided supraclavicular brachial plexus block. Patient did not have clinical features of pneumothorax or drug allergy and was managed with oxygen therapy and salbutamol nebulization. Chest X-ray revealed elevated right hemidiaphragm confirming unilateral phrenic nerve paresis.
Bronchospasm; phrenic nerve blockade; supraclavicular block; ultrasound guided
The posterior interscalene block has been described as an alternative to the lateral interscalene block. However, this technique has not gained popularity because of the close proximity of the approach to vascular and central neural structures.
To describe the posterior interscalene block technique using ultrasound imaging, and to review the history of its evolution.
The use of ultrasound imaging to facilitate the insertion of interscalene catheters using the posterior approach in 11 patients undergoing total shoulder arthroplasty is described.
All 11 patients had satisfactory analgesia in the first 24 h of the postoperative period. None of the patients complained of neck pain, as had been found in earlier techniques using the posterior approach.
This modification of the posterior approach is a safe and effective method for the insertion of interscalene brachial plexus catheters. These catheters are also comfortable for patients and, in the present study, none of the catheters inadvertently fell out.
Brachial plexus ultrasonography; Local anesthetics; Nerve block; Parenteral infusions; Prospective studies
This report describes a patient who had a series of daily interscalene nerve blocks to treat pain following a shoulder manipulation for postsurgical stiffness. She experienced acute respiratory compromise that persisted for many weeks. All typical and unusual causes of these symptoms were ruled out. Her treating pulmonologist theorized that the ipsilateral carotid body had been injured. However, it was subsequently determined that the constellation of symptoms and their prolonged duration were best explained by a poor stress response from Addison's disease coupled with exacerbation of early onset myasthenia gravis. This patient's case is not a typical reaction to interscalene nerve blocks, and thus preoperative testing would not be recommended for myasthenia gravis or Addison's disease without underlying suspicion. We describe this report to inform physicians to consider a workup for these diagnoses if a typical workup rules out all usual causes of complications from an interscalene block.
Interscalene brachial plexus block (ISB) may be followed by cardiovascular instability. Until date, there is no clear picture available about the underlying mechanisms of ISB. In this study, we aimed to determine the changes in heart rate variability (HRV) parameters after ISB and the differences between right- and left-sided ISBs.
We prospectively studied 24 patients operated for shoulder surgery in sitting position and divided them into two respective groups: R (right-sided block = 14 pts) and L (left-sided block = 10 pts). HRV data were taken before and 30 min after the block. Ropivacaine without ephedrine was used for the ISB through an insulated block needle connected to a nerve stimulator. Statistical analysis implemented chi-square, Student's and t-paired tests. Skewed distributions were analyzed after logarithmic transformation.
All the studied patients had successful blocks. Horner's syndrome signs were observed in 33.3% of the patients (R = 5/14, L = 3/10; [P = 0.769]). There were no significant differences in pre-block HRV between the groups. The application of ISB had differential effect on HRV variables: R-blocks increased QRS and QTc durations and InPNN50, while a statistical decrease was seen in InLF. L-blocks did not show any significant changes. These changes indicate a reduced sympathetic and an increased parasympathetic influence on the heart's autonomic flow after R-block.
Based on the obtained results we conclude that ISB, possibly through extension of block to the ipsilateral stellate ganglion, alters the autonomic outflow to the central circulatory system in a way depending on the block's side.
Bradycardia; Heart rate variability; Hypotension; Interscalene block; Stellate ganglion block
Although arthroscopic shoulder surgery is less invasive and painful than open shoulder surgery, it can often cause intra-operative hemodynamic instability and severe post-operative pain. This study was conducted to investigate the efficacy of the interscalene brachial plexus block (IBPB) on intra-operative hemodynamic changes and post-operative pain during arthroscopic shoulder surgery.
After institutional review board approval, 50 consecutive patients that had undergone arthroscopic shoulder surgery under general anesthesia were randomly assigned to one of two groups to evaluate intra-operative hemodynamic changes and post-operative pain control. Group 1 patients received an IBPB with 10 ml of normal saline guided by a nerve stimulator before induction, and Group 2 patients received 10 ml of 0.5% ropivacaine hydrochloride with the same technique. The heart rate and systolic and diastolic blood pressures were recorded before the incision and 1, 3, 5, 10, and 20 minutes after the incision. Pre-operative and post-operative pain was evaluated with a visual analog scale 1, 3, 6, 12, and 24 hours after surgery. The patients were given tramadol as a rescue medication option. The total volume of tramadol that was injected was also evaluated over the same intervals.
Group 2 showed significantly lower systolic and diastolic blood pressures and heart rates intra-operatively compared to Group 1 (P < 0.05). The visual analog scale pain scores, except at 24 hours after surgery, were significantly lower in Group 2 (P < 0.05). The total tramadol consumption significantly reduced in Group 2 (P < 0.05).
IBPB effectively controlled the hemodynamic changes that occurred during arthroscopic shoulder surgery as well as post-operative pain.
Arthroscopy; Brachial plexus; Hemodynamics; Nerve block; Pain; Shoulder
Shoulder arthroplasty procedures are seldom performed on an ambulatory basis. Our objective was to examine postoperative analgesia, nausea and vomiting, patient satisfaction and complications of ambulatory shoulder arthroplasty performed using interscalene brachial plexus block (ISB).
Materials and Methods:
We prospectively examined 82 consecutive patients undergoing total and hemi-shoulder arthroplasty under ISB. Eighty-nine per cent (n=73) of patients received a continuous ISB; 11% (n=9) received a single-injection ISB. The blocks were performed using a nerve stimulator technique. Thirty to 40 mL of 0.5% ropivacaine with 1:400,000 epinephrine was injected perineurally after appropriate muscle twitches were elicited at a current of less than 0.5% mA. Data were collected in the preoperative holding area, intraoperatively and postoperatively including the postanesthesia care unit (PACU), at 24h and at seven days.
Mean postoperative pain scores at rest were 0.8 ± 2.3 in PACU (with movement, 0.9 ± 2.5), 2.5 ± 3.1 at 24h and 2.8 ± 2.1 at seven days. Mean postoperative nausea and vomiting (PONV) scores were 0.2 ± 1.2 in the PACU and 0.4 ± 1.4 at 24h. Satisfaction scores were 4.8 ± 0.6 and 4.8 ± 0.7, respectively, at 24h and seven days. Minimal complications were noted postoperatively at 30 days.
Regional anesthesia offers sufficient analgesia during the hospital stay for shoulder arthroplasty procedures while adhering to high patient comfort and satisfaction, with low complications.
Analgesia; interscalene brachial plexus block; regional anesthesia; satisfaction; shoulder arthroplasty
This study evaluated the effectiveness of a continuous interscalene block (CISB) by comparing it with that of a single interscalene block combined with a continuous intra-bursal infusion of ropivacaine (ISB-IB) after arthroscopic rotator cuff repair.
Patients who had undergone CISB (CISB group; n = 25) were compared with those who had undergone ISB-IB (ISB-IB group; n = 25) for more than 48 hours after surgery. The visual analog scale (VAS) for pain, motor and/or sensory deficit, supplementary analgesics and adverse effects were recorded.
There were no significant differences between the postoperative VAS of the CISB and ISB-IB groups, except at 1 hour after surgery. Their supplementary analgesics of the two groups were similar. Transient motor weakness (52%) and sensory disturbance (40%) of the affected arm were observed in patients in the CISB group. The catheters came out accidentally in 22% of the CISB group but in only 4% of the ISB-IB group.
ISB-IB provides similar analgesia to CISB. However, the ISB-IB group had a lower incidence of neurological deficits and better catheter retention.
Shoulder; Rotator cuff tear; Postoperative pain control; Continuous interscalene block; Single interscalene block with intra-bursal infusion; Arthroscopic rotator cuff repair
Sudden, profound hypotensive and bradycardic events (HBEs) have been reported in more than 20% of patients undergoing shoulder arthroscopy in the sitting position. Although HBEs may be associated with the adverse effects of interscalene brachial plexus block (ISBPB) in the sitting position, the underlying mechanisms responsible for HBEs during the course of shoulder surgery are not well understood. The basic mechanisms of HBEs may be associated with the underlying mechanisms responsible for vasovagal syncope, carotid sinus hypersensitivity or orthostatic syncope. In this review, we discussed the possible mechanisms of HBEs during shoulder arthroscopic surgery, in the sitting position, under ISBPB. In particular, we focused on the relationship between HBEs and various types of syncopal reactions, the relationship between HBEs and the Bezold-Jarisch reflex, and the new contributing factors for the occurrence of HBEs, such as stellate ganglion block or the intraoperative administration of intravenous fentanyl.
Arthroscopy; Bradycardia; Hypotension; Shoulder; Syncope
Arthroscopic shoulder surgery has been performed in the sitting position under interscalene block (ISB). Bradycardia hypotension (BH) episodes have a reported incidence of 13-29% in this setting. We performed a retrospective study to investigate contributing factors to the occurrence of BH episodes.
According to BH episodes, we divided 63 patients into two groups: BH group (n = 13) and non-BH group (n = 50). Anesthetic records and block data sheets were reviewed for demographic data, intraoperative medications, sites of ISB, use of epinephrine in local anesthetics, degree of sensory blockade, and percent change of heart rate or systolic blood pressure (SBP). Statistical analysis was done using Chi square test and Student's t-test.
There were no significant differences in the use of epinephrine in local anesthetics between the two groups. The location of ISB site was different between the two groups in that there were relatively more right-sided ISBs in the BH group than in the non-BH group (P = 0.048). The degree of sensory blockade was lower, but not significantly, in the C8 and T1 dermatomes of the BH group than in the non-BH group (P = 0.060 and 0.077, respectively). There was a relatively higher incidence of fentanyl supplementation in the BH group than in the non-BH group (P = 0.000).
These results suggest that right ISB and perioperative supplementation of fentanyl due to incomplete block are possible contributing factors to the occurrence of BH episodes in the sitting position during shoulder surgery using ISB.
Bradycardia; Contributing factor; Hypotension; Interscalene block
Background and Objectives
The posterior approach to the brachial plexus—or cervical paravertebral block—has advantages over the anterolateral interscalene approach, but concerns regarding “blind” needle placement near the neuraxis have limited the acceptance of this useful technique. We present a technique to place an interscalene perineural catheter that potentially decreases neuraxial involvement with the use of ultrasound guidance.
A 55-year-old man scheduled for total shoulder arthroplasty underwent placement of an interscalene perineural catheter. The posterior approach was selected to avoid the external jugular vein and anticipated sterile surgical field. Under in-plane ultrasound guidance, a 17-gauge insulated Tuohy-tip needle was inserted between the levator scapulae and trapezius muscles, and guided through the middle scalene muscle, remaining less than 2 cm below the skin throughout. Deltoid and biceps contractions were elicited at a current of 0.6 mA, and a 19-gauge stimulating catheter was advanced 5 cm beyond the needle tip, without a concomitant decrease in motor response.
The initial 40 mL 0.5% ropivacaine bolus via the catheter resulted in unilateral anesthesia typical of an interscalene block; and subsequent perineural infusion of 0.2% ropivacaine was delivered via portable infusion pump through postoperative day 4.
Continuous interscalene block using an ultrasound-guided posterior approach is an alternative technique that retains the benefits of posterior catheter insertion, but potentially reduces the risk of complications that may result from blind needle insertion.
continuous peripheral nerve block; perineural catheter; perineural local anesthetic infusion; patient-controlled regional analgesia; ultrasound-guided regional anesthesia
Interscalene block (ISB) is commonly performed using 20-40 mL of local anesthetic. Spread to adjacent structures and consequent adverse effects including paralysis of the ipsilateral hemidiaphragm are frequent. Pain ratings, analgesic requirements, adverse events, satisfaction, function and diaphragmatic excursion were compared following interscalene block (ISB) with reduced initial bolus volumes.
Subjects undergoing arthroscopic rotator cuff repair were randomized to receive 5, 10, or 20 mL ropivacaine 0.75% for ISB in a double-blind fashion (N = 36). Continuous infusion with ropivacaine 0.2% was maintained for 48 h. Pain and diaphragmatic excursion were assessed before block and in the recovery unit.
Pain ratings in the recovery room were generally less than 4 (0-10 NRS) for all treatment groups, but a statistically significant difference was noted between the 5 and 20 mL groups (NRS: 2.67 vs. 0.62 respectively; p = 0.04). Pain ratings and supplemental analgesic use were similar among the groups at 24 h, 48 h and 12 weeks. There were no differences in the quality of block for surgical anesthesia. Dyspnea was significantly greater in the 20 mL group (p = 0.041). Subjects with dyspnea had significant diaphragmatic impairment more frequently (Relative risk: 2.5; 95%CI: 1.3-4.8; p = 0.042). Increased contralateral diaphragmatic motion was measured in 29 of the 36 subjects. Physical shoulder function at 12 weeks improved over baseline in all groups (baseline mean SST: 6.3, SEM: 0.6; 95%CI: 5.1-7.5; 12 week mean SST: 8.2, SEM: 0.46; 95%CI: 7.3-9.2; p = 0.0035).
ISB provided reliable surgical analgesia with 5 mL, 10 mL or 20 mL ropivacaine (0.75%). The 20 mL volume was associated with increased complaints of dyspnea. The 5 mL volume was associated with statistically higher pain scores in the immediate postoperative period. Lower volumes resulted in a reduced incidence of dyspnea compared to 20 mL, however diaphragmatic impairment was not eliminated. Compensatory increases in contralateral diaphragmatic movement may explain tolerance for ipsilateral paresis.
clinicaltrials.gov. identifier: NCT00672100
Regional anesthesia; Diaphragmatic paresis; Interscalene block; Shoulder surgery; Dyspnea; Compensatory diaphragmatic function; Randomized controlled trial