Diabetic Neuropathy and Minimum Effective Anesthetic Concentration of Mepivacaine for Axillary Brachial Plexus Block: A Prospective Observational Study.

Nerves in patients with diabetic neuropathy (DN) show increased susceptibility to local anesthetics, potentially requiring a decreased dose. We investigated whether the minimum effective anesthetic concentration (MEAC) of mepivacaine for successful axillary block is lower in patients with DN than in those without. This prospective observational study included patients with DN (n = 22) and without diabetes (n = 22) at a tertiary care center. Patients received an ultrasound-guided axillary block with 30 mL of mepivacaine for anesthesia. The mepivacaine concentration used in each patient was calculated using Dixon's up-and-down method. A block was considered successful if all four sensory nerves had a score of 1 or 2 within 30 min with no pain during surgery. The primary outcome was the MEAC of mepivacaine, and the secondary outcomes included the minimal nerve stimulation intensity for the musculocutaneous nerve and the occurrence of adverse events. The MEAC50 was 0.55% (95% CI 0.33-0.77%) in patients without diabetes and 0.58% (95% CI 0.39-0.77%) in patients with DN (p = 0.837). The MEAC90 was 0.98% (95% CI 0.54-1.42%) in patients without diabetes and 0.96% (95% CI 0.57-1.35%) in patients with DN (p = 0.949). The stimulation threshold for the musculocutaneous nerve was significantly different between groups (0.49 mA vs. 0.19 mA for patients with vs. without diabetes; p = 0.002). In conclusion, the MEAC of mepivacaine for a successful axillary block is not lower in patients with DN.

Combined Intermediate Cervical Plexus and Costoclavicular Block for Arthroscopic Shoulder Surgery: A Prospective Feasibility Study.

A combined cervical plexus and costoclavicular block provides effective shoulder analgesia without the risk of hemidiaphragmatic paralysis. However, whether this technique can also provide effective anesthesia for shoulder surgery remains unknown. Therefore, this study aimed to assess the feasibility and adverse effects of combined blocks in arthroscopic shoulder surgery. Fifty patients scheduled for arthroscopic shoulder surgery were prospectively enrolled. Intermediate cervical plexus (5 mL of 0.5% ropivacaine) and costoclavicular (20 mL of 0.5% ropivacaine) blocks were administered under ultrasound guidance. The block procedure time, needle pass, patient discomfort, anesthesia quality, onset time, postoperative analgesia quality, adverse events, and patient satisfaction were assessed. Surgical and block success were achieved in 45 (90%; 95% confidence interval [CI], 78-97%) and 44 (88%; 95% CI, 76-95%) patients, respectively. Three patients required local anesthetic supplementation, and two required general anesthesia. The incidence of hemidiaphragmatic paralysis was 12.0% (95% CI, 4.5-24.3%). Postoperative pain control was effective for the first 24 h postoperative. Neurological deficits were not observed. The patients reported a high level of satisfaction. This study revealed that a combined cervical plexus and costoclavicular block provided effective surgical anesthesia for arthroscopic shoulder surgery with a 12% incidence of hemidiaphragmatic paralysis. Further randomized studies comparing this technique with interscalene block are required.

QTc interval prolongation due to spinal anesthesia in patients with and without diabetes: an observational study.

BACKGROUND: Spinal anesthesia and autonomic neuropathy (caused by diabetes) prolong the QTc interval. Changes in the duration of the QTc interval following subarachnoid blockade in patients with diabetes have not been evaluated. We hypothesized that after subarachnoid blockade, QTc interval prolongation would be greater in patients with diabetes than in those without. Accordingly, we compared the QTc interval, T wave peak-to-end interval (Tp-e interval), blood pressure, heart rate, and heart rate variability before and after spinal anesthesia in patients with and without diabetes. METHODS: This prospective observational study (Clinical Research Information Service identifier: KCT0004897) was conducted in a tertiary university hospital and included 24 patients with diabetes mellitus (DM group) and 24 patients without it (control group) who were scheduled for spinal anesthesia. The QTc interval, Tp-e interval, heart rate variability, blood pressure, and heart rate were measured before (T1) and 1 (T2), 5 (T3), and 10 min (T4) following subarachnoid blockade. RESULTS: Ten minutes following subarachnoid blockade, the QTc intervals of patients in the DM group were significantly longer than the baseline values, whereas the change in the QTc interval in the control group was not significant (p < 0.0001 vs. p = 0.06). CONCLUSION: Spinal anesthesia caused a more significant prolongation of the QTc interval in patients with diabetes than in those without.

Impact of High-Flow Nasal Cannula Oxygenation on the Prevention of Hypoxia During Endoscopic Retrograde Cholangiopancreatography in Elderly Patients: A Randomized Clinical Trial.

BACKGROUND: Hypoxia is the most frequently occurring adverse effect during endoscopic retrograde cholangiopancreatography (ERCP) under sedation; thus, oxygen must be properly supplied to prevent a reduction of oxygen saturation. In this study, we intend to verify the preventive effect for hypoxia during ERCP, using a high-flow nasal cannula (HFNC), in elderly patients. METHODS: As a multicenter prospective randomized trial, patients who underwent ERCP with propofol-based sedation were randomly assigned into two groups: Patients in the HFNC group were supplied with oxygen via an HFNC, and those in the standard nasal cannula group were supplied with oxygen via a low-flow nasal cannula. The co-primary end points were the lowest oxygen saturation rate and hypoxia during the overall procedure. RESULTS: A total of 187 patients (HFNC group: 95; standard nasal cannula group: 92) were included in the analysis. Unexpected hypoxia events were more frequently observed among patients in the standard nasal cannula group than among patients in the HFNC group (13% vs. 4%, odds ratio 3.41, 95% confidence interval 1.06-11.00, p = 0.031). The mean of the lowest oxygen saturation rate during ERCP was significantly lower in the standard nasal cannula group than in the HFNC group (95% vs. 97%, p = 0.002). CONCLUSION: Oxygen supplementation with an HFNC can prevent oxygen desaturation and hypoxia events in patients undergoing ERCP under sedation. Trial registration Clinical Research Information Service (CRIS; KCT0004960).

Effects of Local Anesthetic Volume (Standard Versus Low) on Incidence of Hemidiaphragmatic Paralysis and Analgesic Quality for Ultrasound-Guided Superior Trunk Block After Arthroscopic Shoulder Surgery.

BACKGROUND: Relative to interscalene block, superior trunk block (STB) provides comparable analgesia and a reduced risk of hemidiaphragmatic paralysis. However, the incidence of hemidiaphragmatic paralysis remains high when a standard volume (15 mL) of local anesthetic is used. This study aimed to evaluate the effects of local anesthetic volume of STB on the incidence of phrenic nerve palsy, as well as its analgesic efficacy following arthroscopic shoulder surgery. METHODS: Patients scheduled for elective arthroscopic shoulder surgery were randomized to receive ultrasound-guided STB using either 5- or 15-mL 0.5% ropivacaine before general anesthesia. The primary outcome was the incidence of hemidiaphragmatic paralysis at 30 minutes after block. The secondary outcomes were pulmonary function, grade of sensory and motor blockade, pain score, opioid consumption, adverse effects, and satisfaction. RESULTS: Relative to standard-volume STB, low-volume STB was associated with a lower incidence of hemidiaphragmatic paralysis after block (14.3 [4.8%-30.3%] vs 65.7 [46.8%-80.9%]; difference 51.4% [95% confidence intervals {CIs}, 29.0%-67.1%]; P < .0001) and at the postanesthesia care unit (9.4% vs 50.0%; difference 40.6 [95% CI, 18.9%-57.7%]; P = .0004). Pulmonary function was also better preserved in the low-volume group than in the standard-volume group. The extent of the sensory and motor blocks was significantly different between the groups. Pain-related outcomes, satisfaction, and any adverse events were not significantly different between the groups. CONCLUSIONS: Low-volume STB provided a lower incidence of hemidiaphragmatic paralysis with no significant difference in analgesic efficacy relative to standard-volume STB for arthroscopic shoulder surgery.

Comparison of Thoracic Epidural Access with Lateral Decubitus and Shoulder Rotation Positions for Repeat Thoracic Epidural Blockade.

BACKGROUND: Shoulder rotation has been shown to increase the acoustic window of ultrasound for thoracic epidural access. However, this effect of shoulder rotation has not yet been confirmed in clinical practice. OBJECTIVE: This study aimed to evaluate the effects of shoulder rotation on the thoracic epidural blockade in patients with acute or chronic pain in the thoracic region. STUDY DESIGN: Prospective crossover trial. SETTING: Pain clinic of our university in the Republic of Korea. METHODS: Forty patients aged 20 - 80 years with acute or chronic pain in the thoracic region who were scheduled to undergo thoracic epidural blockade more than twice. INTERVENTIONS: The patients underwent repeated fluoroscopy-guided thoracic epidural blockade via the paramedian approach in the lateral decubitus position either with or without shoulder rotation.The primary outcome measure was the attempt time to the confirmed spread of contrast. The number of attempts, total procedure time, vertical interpedicular distance, contrast spreading length, and complications were compared between the 2 positions. RESULTS: The median attempt times in the lateral decubitus and shoulder rotation positions were 138.8 and 132.5 seconds, respectively, and this difference was significant (P = 0.004). Compared with the lateral decubitus position, the shoulder rotation position was also associated with a significantly lower number of attempts (P = 0.03), shorter total procedure time (P < 0.001), and greater vertical interpedicular and contrast spreading distances (P < 0.001 and P = 0.02, respectively). LIMITATIONS: The operator in this study was not blinded to the patient groups. Other researchers observed the operator's procedure and evaluated and recorded the data in an attempt to overcome this bias. However, it was difficult to completely avoid the bias. Second, epidural blockade was performed at various levels (T3-11), and the anatomical features vary among thoracic spine levels. CONCLUSIONS: The study findings demonstrate the clinical benefits of the shoulder rotation position versus the lateral decubitus position in terms of successful epidural access during thoracic epidural blockade using the paramedian approach.

Effect of intravenous dexamethasone on the duration of postoperative analgesia for popliteal sciatic nerve block: a randomized, double-blind, placebo-controlled study.

BACKGROUND: Intravenous (IV) dexamethasone prolongs the duration of a peripheral nerve block; however, there is little available information about its optimal effective dose. This study aimed to evaluate the effects of three different doses of IV dexamethasone on the duration of postoperative analgesia to determine the optimal effective dose for a sciatic nerve block. METHODS: Patients scheduled for foot and ankle surgery were randomly assigned to receive normal saline or IV dexamethasone (2.5 mg, 5 mg, or 10 mg). An ultrasound-guided popliteal sciatic nerve block was performed using 0.75% ropivacaine (20 ml) before general anesthesia. The duration of postoperative analgesia was the primary outcome, and pain scores, use of rescue analgesia, onset time, adverse effects, and patient satisfaction were assessed as secondary outcomes. RESULTS: Compared with the control group, the postoperative analgesic duration of the sciatic nerve block was prolonged in groups receiving IV dexamethasone 10 mg (P < 0.001), but not in the groups receiving IV dexamethasone 2.5 mg or 5 mg. The use of rescue analgesics was significantly different among the four groups 24 h postoperatively (P = 0.001) and similar thereafter. However, pain scores were not significantly different among the four groups 24 h postoperatively. There were no statistically significant differences in the other secondary outcomes among the four groups. CONCLUSIONS: This study demonstrated that compared to the controls, only IV dexamethasone 10 mg increased the duration of postoperative analgesia following a sciatic nerve block for foot and ankle surgery without the occurrence of adverse events.

Bilateral brachial plexus block in a patient with cervical spinal cord injury: A case report.

RATIONALE: Bilateral brachial plexus block (BPB) generally requires a relatively large dose of local anesthetic for a successful block, resulting in a high risk of local anesthetic systemic toxicity. It can also result in inadvertent bilateral phrenic nerve palsy, leading to respiratory failure. Hence, it has not been widely used. However, it can be performed in selected patients. In this report, we present a case of ultrasound-guided BPB for bilateral upper extremity surgery in a patient with cervical spinal cord injury (SCI). PATIENT CONCERNS: A 25-year-old woman with SCI secondary to traumatic fifth cervical spine fracture scheduled for surgical treatment of bilateral elbow fracture received bilateral BPB. DIAGNOSES: Due to the complications of SCI, the patient had incomplete sensory loss, loss of motor function, and complete diaphragmatic paralysis on the right side. INTERVENTIONS: Right infraclavicular and left axillary BPB was performed as the sole anesthetic procedure for bilateral upper extremity surgery. OUTCOMES: Bilateral BPB was successful for bilateral upper extremity surgery. The surgery was uneventful and without further complications. LESSONS: Patients with cervical SCI have a high risk of respiratory complications. Bilateral BPB can be a suitable option for bilateral upper extremity surgery in selected patients. It is imperative to select an appropriate anesthetic technique that preserves respiratory function to minimize the potential risk of respiratory complications.

Acute cervical myelopathy with quadriparesis after cervical transforaminal epidural steroid injection: A case report.

RATIONALE: Cervical transforaminal epidural steroid injection (TFESI), can be an effective tool to improve pain associated with cervical radiculopathy. However, complications related to the procedure have been reported. PATIENT CONCERNS: A 50-year-old woman who experienced acute cervical myelopathy with quadriparesis after cervical TFESI under fluoroscopic guidance. DIAGNOSES: The initial post-procedure cervical MRI revealed acute cervical myelopathy INTERVENTIONS:: She received 1000 mg of methylprednisolone was injected intravenously daily for 3 days OUTCOMES:: Improvement in pain, with the only remaining complaints consisting of lingering mild pain in the left hand and occasional hypoesthesia LESSONS:: Cervical TFESI, despite careful fluoroscopic localization, resulted in spinal cord injury. A spinal cord injury may be treated with conservative treatments, such as medication and rehabilitation.

Inadvertent epidural anesthesia associated with catheterization following continuous psoas compartment block in a patient with scoliosis: A Case report.

RATIONALE: Psoas compartment block (PCB) is typically performed using surface anatomical landmarks and neurostimulation for guidance. However, anatomical anomalies, such as scoliosis, make this technique unreliable, posing a challenge for the anesthesiologist when inducing regional anesthesia. PATIENT CONCERNS: A 69-year-old woman with lumbar scoliosis scheduled for total hip arthroplasty underwent PCB with catheterization. DIAGNOSES: Inadvertent epidural anesthesia with catheterization following PCB was diagnosed using a lumbar radiograph. INTERVENTIONS: Due to hypotension induced by local anesthetic (LA) epidural diffusion, the patient received intravenous hydration and vasopressor. Since bilateral sensory block was noted at the T3 level, with an incomplete motor blockade in both legs, the surgery was performed under epidural anesthesia. OUTCOMES: The patient remained hemodynamically stable throughout the duration of the surgical procedure. The surgery was uneventful and without further complications. LESSONS: Patients with lumbar scoliosis are highly at risk of LA epidural diffusion, following PCB using traditional landmark-based approach. Other nerve-localizing technique can minimize the risk of this complication.

Inadvertent thermal injury following knee arthroscopic surgery in a pediatric patient.

Inadvertent thermal injury can occur in pediatric patients under general anesthesia during knee arthroscopic surgery. Here, we report the case of a 10-year-old boy who underwent knee arthroscopic surgery under general anesthesia. After the surgery, he complained of pain in the left lower part of his chin and was diagnosed as having a thermal burn. At three-month follow-up, he recovered without any abnormalities except mild hypertrophy of the wound area. Although rare, arthroscopic surgery has the potential to cause thermal injury from the light source. We recommend that the light source should be connected to the arthroscope before switching the power on and disconnected after a considerable time of switching the power off when not in use.

A comparison of palonosetron and dexamethasone for postoperative nausea and vomiting in orthopedic patients receiving patient-controlled epidural analgesia.

BACKGROUND: Postoperative nausea and vomiting (PONV) is one of the major concerns after anesthesia and surgery, and it may be more frequent in orthopedic patients receiving patient-controlled epidural analgesia (PCEA). The purpose of this study was to compare the effect of palonosetron and dexamethasone on the prevention of PONV in patients undergoing total joint arthroplasty and receiving PCEA. METHODS: Patients scheduled for total hip or knee arthroplasty under spinal anesthesia/PCEA were randomly allocated to receive either intravenous palonosetron (0.075 mg, n = 50) or dexamethasone (5 mg, n = 50). Treatments were administered intravenously to the patients 30 min before the beginning of surgery. The total incidence of PONV and incidence in each time period, severity of nausea, need for rescue anti-emetics, pain score, and adverse effects during the first 48 h postoperatively were evaluated. RESULTS: The total incidence of PONV was lower in the palonosetron group compared with the dexamethasone group (18.4% vs. 36.7%, P = 0.042), but there were no statistically significant differences in incidence between the groups at all time points. No significant intergroup differences were observed in the severity of nausea, use of rescue anti-emetics, pain score, and adverse effects. CONCLUSIONS: Although there were no significant differences in the incidence of PONV between the treatment groups at all time points, intravenous palonosetron reduced the total incidence of PONV in orthopedic patients receiving PCEA compared with dexamethasone.

The effect of ketorolac and dexamethasone on the incidence of sore throat in women after thyroidectomy: a prospective double-blinded randomized trial.

BACKGROUND: We evaluated the effect of two drugs with anti-inflammatory action, dexamethasone and ketorolac, on reduction of postoperative sore throat (POST) after general anesthesia with endotracheal intubation in patients undergoing thyroidectomy. METHODS: One hundred and ninety-two female patients scheduled to undergo general anesthesia with endotracheal intubation for thyroidectomy were enrolled in this prospective study. Participants were randomly allocated to receive intravenous medication; placebo (Group C, n = 45), ketorolac 30 mg immediately before intubation (Group Kpre, n = 47), ketorolac 30 mg at the end of surgery (Group Kpost, n = 45) and dexamethasone 10 mg (Group D, n = 43). The incidence and severity of POST and hoarseness were evaluated at 1, 6 and 24 hours after surgery. RESULTS: Incidences and severities of POST at rest and during swallowing in first 6 hours after extubation were comparable among 4 groups. At 24 hours postextubation, the incidence (P = 0.002, 95% CI of proportion differences; 0.05-0.39) and severity (P = 0.008) of POST during swallowing were significantly lower in group D than in group C. Kpre and Kpost groups did not show a greater reduction in POST than group C, despite lower rescue analgesic requirement at 1 hour after extubation in group Kpre (P = 0.006; 95% CI of proportion differences; 0.07-0.38). No intergroup differences were observed in incidences of hoarseness or adverse events. CONCLUSIONS: Intravenous administration of dexamethasone 10 mg, but not ketorolac, before induction of anesthesia reduces the incidence and severity of POST during swallowing at 24 hours after thyroidectomy.

Segregation for reduction of regulated medical waste in the operating room: a case report.

One-third of all hospital-regulated medical waste (RMW) comes from the operating room (OR), and it considerably consists of disposable packaging and wrapping materials for the sterilization of surgical instruments. This study sought to identify the amount and type of waste produced by ORs in order to reduce the RMW so as to achieve environmentally-friendly waste management in the OR. We performed an initial waste segregation of 4 total knee replacement arthroplasties (TKRAs) and 1 total hip replacement arthroplasty, and later of 1 extra TKRA, 1 laparoscopic anterior resection of the colon, and 1 pelviscopy (with radical vaginal hysterectomy), performed at our OR. The total mass of non-regulated medical waste (non-RMW) and blue wrap amounted to 30.5 kg (24.9%), and that of RMW to 92.1 kg (75.1%). In the course of the study, we noted that the non-RMW included recyclables, such as papers, plastics, cardboards, and various wrapping materials. The study showed that a reduction in RMW generation can be achieved through the systematic segregation of OR waste.

Prolonged hemidiaphragmatic paresis following continuous interscalene brachial plexus block: A case report.

Interscalene brachial plexus block provides effective anesthesia and analgesia for shoulder surgery. One of the disadvantages of this technique is the risk of hemidiaphragmatic paresis, which can occur as a result of phrenic nerve block and can cause a decrease in the pulmonary function, limiting the use of the block in patients with reduced functional residual capacity or a preexisting pulmonary disease. However, it is generally transient and is resolved over the duration of the local anesthetic's action.We present a case of a patient who experienced prolonged hemidiaphragmatic paresis following a continuous interscalene brachial plexus block for the postoperative pain management of shoulder surgery, and suggest a mechanism that may have led to this adverse effect.Nerve injuries associated with peripheral nerve blocks may be caused by several mechanisms. Our findings suggest that perioperative nerve injuries can occur as a result of combined mechanical and chemical injuries.