Risk Of Local Toxicity Research Articles

Mitigating the Risk of Local Anesthetic Toxicity with Truncal Blocks.

Mitigating the Risk of Local Anesthetic Toxicity with Truncal Blocks.

Incidence of post-dural lumbar puncture headache (PDLPH) in comparison between emergency and elective lower segment cesarean section (LSCS) with 26G Quincke-Babcock cutting-beveled spinal needle.

C-section is usually performed under spinal anesthesia also known as a subarachnoid block (SAB) over general anesthesia. Because of the lesser amount of dose used, there is a lower risk of local anesthetic toxicity and minimal transfer of drugs to the fetus. Obstetric patients have a higher risk of having post-dural puncture headache (PDPH). PDPH occurs due to leakage of the cerebrospinal fluid (CSF) through the hole created by a spinal needle. There are many elements affecting the frequency of PDPH, these elements can also consist of age, female sex, needle size, and types, pregnancy, preceding records of PDPH, median-paramedian distinction in approach, a puncture level. PDPH is commonly in the form of a frontal, occipital, or retro-orbital headache that starts in 12-72 h after the dural puncture and will increase when standing and decrease when lying down or resting. We aimed to learn about headache frequency between elective and emergency lower segment cesarean section using 26-G Quincke spinal needle in full-term pregnant patients. To study the incidence of PDPH using the 26G Quincke spinal needle. To analyze the causal factors/determinants such as adequate preloading of fluids, size of spinal needle, number of pricks, and technique of lumbar puncture effects on the incidence of PDPH. This study is a prospective questionnaire-based comparative observational study using the convenience sampling method. The patients were interviewed with a structured questionnaire at the Symbiosis University Hospital and Research Centre, Lavale, Pune. The patients observed for the study were between 20 and 40 of age group, posted for emergency or elective lower segment cesarean section, with body mass index (BMI) less than 14.5 to 24.9 and with ASA I and II grades. Patients with any comorbidities, recurrent headaches, obesity, and spine deformity were excluded. According to the review of the literature and with the help of a formula, the sample size was calculated as 20; 10 patients for elective LSCS, and 10 patients for emergency LSCS. Out of 20 patients, 10 patients were posted for elective LSCS, and the rest 10 patients were for emergency LSCS under spinal anesthesia. The incidence of PDPH was found only in 2 out of 10 emergency LSCS patients, and no patients from elective LSCS cases showed up with the incidence of PDPH.

Continuous Spinal Anaesthesia for Below Knee Amputation in High Risk Case: A Case Report

Introduction: Lower limb ischemia, peripheral arterial disease, and diabetes mellitus are considered the major cause for limb amputations in more than 50% of cases. These patients have increased risk of perioperative mortality and morbidity due to additional comorbidities, such as cardiac diseases. Continuous spinal anaesthesia (CSA) provides better cardiovascular stability, less local anaesthetic requirement, better control of anaesthesia level and lower risk of local anaesthetic toxicity were reported in the CSA technique compared with a single-dose spinal anaesthesia technique. We reported a high-risk patient who underwent below knee amputation surgery under CSA. Case Report: This is a 50-year-old male, American Society of Anaesthesiologists (ASA) III, dilated cardiomyopathy admitted for below knee amputation surgery. Preop vitals are stable. Blood investigations are normal. Chest radiography showed cardiomegaly, and echocardiography revealed sinus tachycardia with poor R wave progression and low ejection fraction (EF) of 20%. Continuous spinal anaesthesia was planned for the procedure, during the surgery total amount of fluid given was 40 mL of crystalloids at the rate of 20ml/hr. Intraop vitals stable. The patient was transferred to post op ward following the removal of spinal catheter. No anaesthetic complications noted. Conclusion: We reported the successful anaesthetic management of a patient with coronary artery disease and low ejection fraction undergoing below knee amputation surgery. CSA technique with low dose hyperbaric bupivacaine provided safe and effective ananaesthesia with minimal haemodynamic changes for this case.

Comparative retrospective review of perioperative analgesia using ultrasound-guided programmed intermittent erector spinae plane block for video-assisted thoracoscopic lobectomy

BackgroundThe retrospective cohort study was conducted to estimate the opioid-sparing anesthesia and limited side-effects with ultrasound (US)-guided ESPB using programmed intermittent bolus (PIB) or continuous infusion (CI) and standard opioid-based anesthesia in patients undergoing video-assisted thoracoscopic lobectomy (VATS).MethodsPatients underwent VATS were stratified into either control group or one of the two ESPB groups in a 1:2:2 ratio depending on whether PIB was implemented or not. The primary endpoint was intra- and post-operative opioids consumption over the first 48 h following surgery.ResultsA total of 180 cases were included in the analysis. Cumulative perioperative opioid administration was found to be significantly different between PIB, CI and control group (both p < 0.001), and between PIB and CI group (p = 0.028). More specifically, the mean was 305.30 ± 51.35 mg, 339.68 ± 56.07 mg and 468.91 ± 79.84 mg in PIB, CI and control group. NRS scores at rest across all postoperative times were comparable in two ESPB groups, while significantly lower than control group, however, scores during exercising at postoperative 3, 6, 12 h were significantly lower in PIB group as compared to CI group. A wider anesthetized dermatomes with PIB was observed at 6, 24 and 48 h as opposed to the CI. The mean of levobupivacaine plasma concentration was significantly lower for PIB at postoperative 0.5, 12, 24 and 48 h after initiation than CI. However, local anesthetic toxicity was not observed in any of the two ESPB groups.ConclusionsWhen US-guided ESPB using PIB was performed preoperatively, it contributed to the minimization of intra- and post-operative opioid consumption due to better analgesia with a wider anesthetic dermatome opposed to conventional CI, whereas, it was also associated with lower risk of local anesthetic toxicity because of lower plasma concentration of levobupivacaine.

MP16-09 SAFETY AND EFFICACY OF TRANSURETHRAL RESECTION OF BLADDER TUMOUR COMPARING SPINAL ANAESTHESIA TO SPINAL ANAESTHESIA WITH AN OBTURATOR NERVE BLOCK: A SYSTEMATIC REVIEW AND META-ANALYSIS

You have accessJournal of UrologyBladder Cancer: Non-invasive II (MP16)1 Sep 2021MP16-09 SAFETY AND EFFICACY OF TRANSURETHRAL RESECTION OF BLADDER TUMOUR COMPARING SPINAL ANAESTHESIA TO SPINAL ANAESTHESIA WITH AN OBTURATOR NERVE BLOCK: A SYSTEMATIC REVIEW AND META-ANALYSIS Anil Krishan, Angus Bruce, Shehab Khashaba, Mohamed Abouelela, and Syed Ali Ehsanullah Anil KrishanAnil Krishan More articles by this author , Angus BruceAngus Bruce More articles by this author , Shehab KhashabaShehab Khashaba More articles by this author , Mohamed AbouelelaMohamed Abouelela More articles by this author , and Syed Ali EhsanullahSyed Ali Ehsanullah More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002001.09AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: To investigate whether spinal anaesthesia with an obturator nerve block (SA+ONB) can be effectively employed for transurethral resection of bladder tumours (TURBT) during the COVID-19 pandemic to improve patient outcomes whilst also avoiding aerosol-generating procedures. We aimed to compare outcomes of TURBT using spinal anaesthesia (SA) alone versus SA+ONB in terms of rates of obturator reflex, bladder perforation, incomplete tumour resection, tumour recurrence and local anaesthetic toxicity. METHODS: We conducted a comprehensive search of electronic databases (MEDLINE, PUBMED, EMBASE, CINAHL, CENTRAL, SCOPUS, Google Scholar and Web of Science), identifying studies comparing the outcomes of TURBT using spinal anaesthesia versus spinal with an obturator nerve block. The Cochrane risk-of-bias tool for RCTs and the Newcastle-Ottawa scale for observational studies were used to assess the included studies. Random effects modelling was used to calculate pooled outcome data. RESULTS: Searches of electronic databases resulted in 107 articles, from which four randomised control trials (RCTs) and three cohort studies met the eligibility criteria, enrolling a total of 448 patients. The use of spinal anaesthesia with an obturator nerve block was associated with a significantly reduced risk of obturator reflex (p <0.00001), bladder perforation (p=0.02), incomplete resection (p <0.0001) and 12-month tumour recurrence (p=0.005). Obturator nerve block was not associated with an increased risk of local anaesthetic toxicity (0/159). CONCLUSIONS: Our meta-analysis suggests that TURBT employing spinal anaesthesia with an obturator nerve block is superior to the use of spinal anaesthesia alone. During the COVID-19 pandemic, where avoidance of aerosol-generating procedures (AGPs) such as a general anaesthesia is paramount, the use of an obturator nerve block with spinal anaesthesia is essential for the safety of both patients and staff without compromising care. Further high-quality RCTs with adequate sample sizes are required to compare the different techniques of obturator nerve block as well as comparing this method to general anaesthesia with complete neuromuscular blockade. Source of Funding: Nil © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e299-e300 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Anil Krishan More articles by this author Angus Bruce More articles by this author Shehab Khashaba More articles by this author Mohamed Abouelela More articles by this author Syed Ali Ehsanullah More articles by this author Expand All Advertisement Loading ...

Blocking Blindly: How to Navigate Risks of Local Anesthetic Toxicity When Liposomal Bupivacaine Has Been Used and the Patient Is Still in Pain.

Blocking Blindly: How to Navigate Risks of Local Anesthetic Toxicity When Liposomal Bupivacaine Has Been Used and the Patient Is Still in Pain.

COMPARATIVE STUDY OF COLOADING AND PRELOADING WITH BALANCED CRYSTALLOIDS FOR PREVENTION OF POST-SPINAL HYPOTENSION IN PATIENTS UNDERGOING ELECTIVE CAESAREAN SECTION

Background Spinal anesthesia is the most common anaesthetic technique for cesarean delivery due to its rapid onset, a dense neural block, little risk of local anesthetic toxicity and minimal transfer of drug to the fetus, as well as little risk of failure of block However incidence of hypotension is one of disadvantages of this technique because of sympathetic blockade. Conventionally, crystalloid preloading has been used to prevent spinal anaesthesia induced hypotension, but it has shown varying results. Therefore, focus is on crystalloid coloading for prevention of spinal induced hypotension. Method An observational prospective study was done on 60 parturients undergoing elective cesarean delivery. Patients were randomized into 2 groups who received either crystalloid preloading or coloading. Parameters assessed were, heart rate, systolic blood pressure, diastolic blood pressure, mean arterial pressure, incidence of hypotension and use of mephentermine. Result In this study, there was significant difference in the incidence of hypotension in both the groups, which was more in preload group. Total dose of mephentermine used was also significantly more in preload group. Conclusion We concluded that crystalloid coloading is beneficial to prevent post-spinal hypotension in patients undergoing elective cesarean delivery, as compared to patients receiving preloading fluid.

Comparison between Hypertonic Saline (3%) and Normal Saline (0.9%) as a Preload before Spinal Anaesthesia in Caesarean Section

Background: spinal anesthesia is frequently used for cesarean delivery because of its rapid onset, a dense neural block, little risk of local anesthetic toxicity and minimal transfer of drug to the fetus. General anesthesia is preferred in emergency obstetric situations, such as cord prolapse, in which there is a need for reliable induction, and also bleeding placenta previa. Unfortunately it is frequently accompanied by hypotension, which may be defined in absolute terms as a systolic blood pressure (SBP) of 90 or 100 mmHg or in relative terms as a percentage (20% fall from baseline). Aim of the Work: the aim of this study is to compare hypertonic saline (3%)and normal saline (0.9%) in preventing spinal induced hypotension. Patients and Methods: in our study, 40 patients were randomly divided into 2 equal groups: Group A: received hypertonic saline (3%) (4ml/kg) . Group B: received normal saline (0.9%)(13ml/kg). Results: our study showed that hypertonic saline (3%) was more effective than normal saline to prevent spinal induced hypotension and it did not affect the neonatal outcome. Conclusion: neonatal outcome was excellent with the use of either hypertonic saline (3%) or normal saline (0.9%) as a preload for the parturient who received spinal anesthesia before cesarean section.

Tumescent anaesthesia: its applications and well tolerated use in the out-of-operating room setting.

Tumescent anaesthesia is a method of administering dilute local anaesthetic into the subcutaneous tissue. Many anaesthesiologists are unfamiliar with the technique, its applications and potential risks. The maximum safe dose of lidocaine with epinephrine in tumescent anaesthesia for liposuction is probably between 35 and 55 mg/kg. Without liposuction, the maximum dose of lidocaine with epinephrine should be no more than 28 mg/kg. After tumescent infiltration for liposuction, serum lidocaine concentrations peak between 12 and 16 h after injection. When tumescent lidocaine without epinephrine is used for endovenous laser therapy, peak serum lidocaine concentrations are observed much earlier, between 1 and 2 h after injection. Slow administration of more dilute concentrations of local anaesthetic decreases the risk of local anaesthetic systemic toxicity. Although appealing because of its ability to provide prolonged analgesia, high doses of local anaesthetic are frequently administered using the tumescent technique, and absorption of local anaesthetic from the subcutaneous tissue is variable. When caring for patients having procedures in which tumescent anaesthesia is used, the risk of local anaesthetic toxicity should be acknowledged and lipid emulsion should be available for prompt treatment if needed.

Levobupivacaine absorption pharmacokinetics with and without epinephrine during TAP block: analysis of doses based on the associated risk of local anaesthetic toxicity.

Cases of local anaesthetic systemic toxicity (LAST) periodically occur following transversus abdominal plane (TAP) blocks. The aim of this study was to characterize levobupivacaine absorption pharmacokinetics, with and without epinephrine, and estimate the risk of LAST, based on a previously reported toxic threshold. Previously reported data from 11 volunteers receiving ultrasound-guided TAP blocks with and without epinephrine on two independent occasions were analysed. Serial venous concentrations were measured for 90min. A pharmacokinetic analysis was performed using the NONMEM statistical programme. The use of epinephrine in the solution was included in the analysis of covariates. The associated risk of LAST symptoms associated with different levobupivacaine dose schemes with and without epinephrine was estimated in 1000 simulated subjects. A one-compartment first-order input and elimination model adequately fit the levobupivacaine data. Epinephrine prolonged the levobupivacaine absorption half-life {4.22 [95 % confidence interval (CI) 2.53-6.50] vs. 7.02 [95 % CI 3.74-14.1]; p < 0.05} and reduced its relative bioavailability (0.84; 95 % CI 0.72-0.97; p < 0.05) The derived model predicts that levobupivacaine dose schemes should be halved from 3mg kg(-1) body weight with epinephrine to 1.5mg kg(-1) without epinephrine to obtain a comparable risk of anaesthetic toxicity symptoms of approximately 0.1%. Our results strongly support the addition of epinephrine to the local anaesthetic solution, especially when doses of levobupivacaine of >1.5mg kg(-1) are required. Recommendations regarding the maximum allowable doses of local anaesthetics should consider population analysis to determine safer dosage ranges.

The efficacy of simultaneous bilateral axillary brachial plexus block under the guidance of neurostimulator or ultrasound: a prospective study.

This study was designed to investigate the risk of local anesthetic toxicity and efficacy of simultaneous bilateral axillary brachial plexus block performed under the guidance of ultrasound or a neurostimulator. One hundred and twenty patients who were anesthetized with bilateral axillary plexus block simultaneously between February 2012 and March 2014 were enrolled in the study. The patients were anesthetized under the guidance of a neurostimulator (group N, n=60) or ultrasound (group U, n=60). The block performance time, procedure-related pain, adverse events, total and free plasma concentrations of ropivacaine, and other data were recorded. The comparison was analyzed statistically. The block performance time, and onset of the sensory and motor block, of group N was longer than that of group U (p<0.001). The procedure-related pain of group N was more serious than that of group U (p<0.05). The patient satisfaction rate of group U was higher than that of group N (p<0.05). The total plasma concentrations of ropivacaine in group N were comparable to those of group U, except for the value at 50min after injection (p<0.05). The free plasma concentrations of ropivacaine of group N at 5min were significantly higher than that of group U (p<0.001). No apparent serious adverse events were observed perioperatively in both groups. Simultaneous bilateral axillary brachial plexus block guided by neurostimulator or ultrasound in bilateral distal upper extremity surgery seems to have a low risk of local anesthetic toxicity and to be effective. The ultrasound-guided block is superior in terms of providing the same degree of anesthesia with shorter duration, less pain, and faster onset of sensory and motor blockades, which is important in clinical practice.

Continuous chloroprocaine infusion for thoracic and caudal epidurals as a postoperative analgesia modality in neonates, infants, and children.

Neonates and infants have decreased metabolic capacity for amide local anesthetics and increased risk of local anesthetic toxicity compared to the general population. Chloroprocaine is an ester local anesthetic that has an extremely short plasma half-life in infants as well as adults. Existing reports support the safety and efficacy of continuous chloroprocaine epidural infusions in neonates and young infants during the intraoperative period. Despite this, continuous chloroprocaine epidural infusion may be an under-utilized method of postoperative analgesia for this patient population. In particular, it may improve pain control in neonates and infants with incisions stretching many dermatomes or those with hepatic impairment. We retrospectively reviewed our experience over 4 years with continuous chloroprocaine epidural infusions in neonates, infants, and children with a focus on the postoperative management of pain. Twenty-one pediatric patients received continuous 2-chloroprocaine epidural infusions for postoperative pain management from January 2010 to April 2014 for thoracic, abdominal, and limb procedures. The epidural infusion consisted of 1.5% chloroprocaine or 1.5% chloroprocaine with fentanyl. Tabulating the morphine and hydromorphone used for rescue analgesia, the median (interquartile range) opioid consumption (mg·kg(-1) ·day(-1) of intravenous morphine equivalents) for the first, second, and third 24-h postoperative periods were 0.02 (0-0.48), 0.30 (0-0.44), and 0.14 (0-0.29), respectively. Examining the total fentanyl usage, the median (interquartile range) fentanyl consumption (μg·kg(-1) ·day(-1)) for first, second, and third 24-h postoperative periods were 3.89 (0.41-7.24), 0 (0.00-4.06), and 0 (0.00-0.51), respectively. The median N-PASS score assessed every 6 h from 0 to 72 h postoperatively was 0, 1, 2, 0, 0, 1, 0, 0, 0, 0, 1, 0, and 0, respectively. The median FLACC score assessed every 6 h from 0 to 72 h postoperatively was 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, and 0, respectively. The results suggest that chloroprocaine offers an efficacious alternative to the amide local anesthetics for postoperative epidural analgesia in the pediatric population.

Pain-associated Respiratory Failure in Chest Trauma

Pain-associated Respiratory Failure in Chest Trauma

Low concentrations of lidocaine for inguinal hernia repair under local infiltration anaesthesia

A randomized, double-blind, prospective, controlled study to determine the lowest concentration of lidocaine that provides satisfactory anaesthesia and analgesia for inguinal hernia repair. Patients with inguinal hernia undergoing tension-free mesh repair under local infiltration anaesthesia were randomized to receive 0.25% (Group A), 0.33% (Group B) or 0.5% (Group C) lidocaine. Total dose and volume of lidocaine consumed and intraoperative visual analogue scale (VAS) pain scores were recorded for each patient. Each patient's degree of satisfaction and the incidence of anaesthesia- and procedure-related complications were recorded and assessed. A total of 120 patients were randomized. There were no between-group differences in median VAS scores, degree of satisfaction, volume of lidocaine consumed or incidence of complications. Patients in group A consumed significantly lower doses of lidocaine than those in both other groups. The mean dose of lidocaine consumed in group A was significantly lower but exerted similar efficacy to that in the other groups, and may lead to a lower risk of local anaesthetic toxicity.

NEONATAL SÜNNET İÇİN UYGULANAN İKİ FARKLI BUPİVAKAİN DOZUNUN KARŞILAŞTIRILMASI: RANDOMİZE KLİNİK ÇALIŞMA

We aimed to compare the analgesia quality of caudal block of low volume, high concentration bupivacaine to the conventionally used volumes and concentrations of the drug in neonates undergoing circumcision with sole caudal anesthesia.Fifty neonates, undergoing circumcision were randomly assigned to low volume high concentration (group LVHC, n=25) and control groups (group C, n=25). Both groups received a caudal injection: Group LVHC 0.5 ml/kg bupivacaine 0.375% (1.875 mg/kg) and group C 1 ml/ kg bupivacaine 0.25% (2.5 mg/kg). Hemodynamic parameters, block onsets and analgesia periods were compared among the groups. Pain scores were evaluated hourly for 3 hours postoperatively with NIPS (neonatal infant pain score). Statistical analyses were performed with Student's t-test for continuous variables. X(2) and Mann-Whitney U-tests were used for nominal and/or categorical variables.Demographic, hemodynamic data, block onset time (group LVHC and C values were 4.9 +/- 1 vs 5.2 +/- 2 mins, respectively; p=0.53) was similar and postoperative median NIPS (a median value of 0 at postoperative 1, 2, and 3. hours) were identical among the groups (p=0.7, p=0.9, p=1). None of the neonates required additional analgesic for the first 24 hours following the surgery; therefore postoperative analgesic requirement was similar among the groups (p>0.1).Low volume high concentration caudal bupivacaine provided a similar perioperative analgesia quality, time and safety profile compared to conventional bupivacaine doses in awake neonates undergoing circumcision. Low volume, high concentration bupivacaine may be used to reduce the risk of local anesthetic toxicity in outpatient neonates.

Case report: Sequential bilateral upper extremity intravenous regional anesthesia with chloroprocaine

This case report describes the novel use of sequential bilateral upper extremity intravenous regional anesthesia with 2-chloroprocaine for bilateral endoscopic carpal tunnel decompression. A 49-yr-old female, American Society of Anesthesiologists physical status I, presented for outpatient bilateral carpal tunnel release. Sequential bilateral intravenous regional anesthesia was performed with 0.5% 2-chloroprocaine 30mL per arm using a double upper arm tourniquet. Intraoperative sedation consisted of midazolam and fentanyl. Tourniquet times for the right and left arms were 28 and 19min, respectively. After deflation of each tourniquet, mild limb twitching occurred but resolved immediately after administration of intravenous midazolam. The patient made a rapid recovery, and she was discharged home uneventfully. Bilateral sequential intravenous regional anesthesia with 2-chloroprocaine is effective for upper extremity surgery of short duration. Recommendations to minimize the risk of local anesthetic toxicity are reviewed.

Clinical Utility of Low-Volume Ultrasound-Guided Interscalene Blockade

The purpose of this series is to describe cases in which ultrasound guidance was used to allow patients to receive the benefits of regional anesthesia while safely circumventing traditional contraindications to interscalene blockade (ISB). Targeted low-volume ISB was performed in 3 patients in whom this procedure would typically be contraindicated because of phrenic nerve blockade or risk of local anesthetic toxicity. A patient with severe respiratory dysfunction, a patient undergoing bilateral shoulder surgery, and a patient requiring awake fiberoptic intubation underwent low-volume ultrasound-guided ISB. The ultrasound technique involved the use a low local anesthetic volume, anatomic identification of the brachial plexus trunk, needle placement opposite the phrenic nerve position, and control over local anesthetic spread. In both patients in whom diaphragmatic paralysis was a concern, postoperative respiratory parameters indicated successful regional analgesia without evidence of phrenic nerve blockade. In the patient requiring an additional regional anesthetic procedure, ISB was performed with a local anesthetic volume low enough to avoid exceeding toxic safety thresholds. Although further studies are warranted, we report on 3 cases in which ultrasound guidance was used to allow patients to receive the benefits of regional anesthesia while safely avoiding standard contraindications to ISB. Ultrasound technology may allow providers to perform low-volume brachial plexus blockade while avoiding issues related to phrenic nerve blockade and systemic local anesthetic toxicity.

Thoracic Paravertebral Block (Pvb) Analgesia

Paravertebral blockade is a safe and effective technique for intraoperative and postoperative management of acute surgical pain. The block may be performed as a single injection or a catheter may be inserted to allow for the continuous or bolus administration of a long acting local anaesthetic. This mode of analgesia is not considered to be a stand alone technique (in contrast to epidural analgesia) and most patients will require additional analgesia (usually parenteral patient controlled analgesia). Compared to epidural analgesia, the paravertebral administration of analgesia is considered to be safer in anti-coagulated patients, but the risk of local anaesthetic toxicity remains. There is little published about the care of patients receiving this form of analgesia. This article provides an overview of the technique of thoracic paravertebral analgesia, the choice of analgesics and side effects together with recommendations for patient care.

The effects of adding diphenhydramine hydrochloride to lidocaine in intravenous regional anaesthesia

This study aimed to evaluate whether diphenhydramine hydrochloride (DPH) could be used to reduce the dose of lidocaine for intravenous regional anaesthesia (IVRA). Sixty patients undergoing upper limb operations were divided into three groups (20 each). All patients received IVRA as follows: group 1 received 3 mg/kg lidocaine, group 2 received 40 mg DPH and 1.5 mg/kg lidocaine, and group 3 received 1.5 mg/kg lidocaine diluted to 40 ml with 0.9% saline solution. The onset of sensory block was tested by a pinprick. The duration of anaesthesia time was also recorded. Intraoperative pain was assessed using a five point pain score system. Side effects during surgery and after release of the tourniquet were recorded. Only 4 patients in group 3 had sufficient analgesia. Therefore, the patients in group 3 were excluded from the study. Data from 40 patients (group 1 and 2) were analysed. The onset time of sensory block was significantly shorter in group 1 than group 2 (2.4 ± 1.54 min and 6.85 ± 1.46 min, respectively). The tourniquet pain time was also significantly longer in group 1 than in group 2 (57.15 ± 10.90 min and 42.65 ± 9.67 min, respectively). One patient from each group experienced tinnitus for 30-60 s, and 4 patients in group 2 had minimal sedation after tourniquet release. According to our results, DPH is a safe and useful adjunct to IVRA in minor procedures of short duration. Decreasing the dose of lidocaine also decreases the risk of local anaesthetic toxicity in the event of accidental release of tourniquet pressure.

Ambulatory Continuous Perineural Infusion: Are We Ready?

Assistant Professor; Department of Anesthesiology; klein006@mc.duke.eduAssociate Professor; Department of AnesthesiologyAssistant Professor; Department of AnesthesiologyVisiting Associate; Department of AnesthesiologyProfessor; Department of Surgery; Duke University Medical Center; Durham, North CarolinaIn Reply:—We thank Chelly et al. for their interest in our case report that described major ambulatory surgery with continuous regional anesthesia and a disposable infusion pump. Although we appreciate their comments, we believe the use of continuous local anesthetic infusions at home is an investigational area of pain control. As a result, despite their institutional bias, many of the issues they highlight, such as the ideal location of catheter placement, dosing method and regimen, and appropriate patient follow-up, remain to be defined with evidence-based medicine. The case report represents a novel application of available technology to highlight the potential benefit this method could have for outpatient pain management, not a definitive treatment algorithm.As we attempt to define an appropriate standard of care for ambulatory perineural infusion, vigilance concerning the risk of local anesthetic toxicity occurring outside of the hospital is essential. In our group, we go to great lengths to avoid such complications. The description by Chelly et al. of patients being sent home with brief instructions and a phone number is inaccurate. As we mentioned in the case report, careful patient selection is essential. In addition, at our institution, the standard of care for each patient is to receive 24-h, 7-day, and 3-week follow-up telephone calls, which are tracked in an automated database. Individual patients are also followed-up at home by physician house calls and home healthcare nurses. Deciding the level of care is based on individual clinician judgment on a case-by-case basis.We agree with Chelly et al. that ambulatory care should provide the same level of care as in-patient care. However, we believe that ambulatory care can provide the same quality of health care as in-patient care, without the same level of nursing and medical intervention suggested by Chelly et al. Removing a continuous local anesthetic catheter at home is one example. Patients routinely remove surgical drains that lie within joint spaces and wounds without the supervision of a physician. Extending this to perineural catheters seems feasible. Furthermore, choosing the appropriate anatomic site for catheter insertion should be based on the site of surgery, patient habitus, and desired postoperative analgesia, not to simply facilitate a clinician’s ease of view of the catheter site.The rapid growth of ambulatory anesthesia and the evolution of outpatient surgical techniques will demand that we move forward from traditional pain management strategies. This will necessitate incorporation of the numerous successful variations in community practice. Given the 50 h of postoperative analgesia provided with this technique in an ambulatory setting, the success we have seen in placing more than 1,000 continuous local anesthetic catheters for inpatient treatment in our ambulatory care unit, and the success discussed in the literature, we believe further investigation of outpatient continuous local anesthetic catheters is warranted. It is our goal to define the safety and effectiveness of this treatment method by prospective randomized trials performed by a core of professionals interested in developing this field, and not simply by individual or institutional tradition.