Intrathecal Administration Of Bupivacaine Research Articles

Effect of intravenous palonosetron on hypotension induced by spinal anesthesia for cesarean section: A randomized controlled trial.

The aim of this study was to evaluate the impact of intravenous palonosetron compared to ondansetron on hypotension induced by spinal anesthesia in women undergoing cesarean section. Fifty-four women scheduled for elective cesarean section were, randomly allocated to ondansetron group (n = 27) or palonosetron group (n = 27). Ten minutes prior to the administration of spinal anesthesia, participants received an intravenous injection of either ondansetron or palonosetron. A prophylactic phenylephrine infusion was initiated immediately following the intrathecal administration of bupivacaine and fentanyl. The infusion rate was titrated to maintain adequate blood pressure until the time of fetal delivery. The primary outcome was total dose of phenylephrine administered. The secondary outcomes were nausea or vomiting, the need for rescue antiemetics, hypotension, bradycardia, and shivering. Complete response rate, defined as the absence of postoperative nausea and vomiting and no need for additional antiemetics, were assessed for up to 24 hours post-surgery. No significant differences were observed in the total dose of phenylephrine used between the ondansetron and palonosetron groups (387.5 μg [interquartile range, 291.3-507.8 μg versus 428.0 μg [interquartile range, 305.0-507.0 μg], P = 0.42). Complete response rates also showed no significant differences between the groups both within two hours post-spinal anesthesia (88.9% in the ondansetron group versus 100% in the palonosetron group; P = 0.24) and at 24 hours post-surgery (81.5% in the ondansetron group versus 88.8% in the palonosetron group; P = 0.7). In addition, there was no difference in other secondary outcomes. Prophylactic administration of palonosetron did not demonstrate a superior effect over ondansetron in mitigating hemodynamic changes or reducing phenylephrine requirements in patients undergoing spinal anesthesia with bupivacaine and fentanyl for cesarean section.

Effects Of Low Doses Of Intrathecal Clonidine And Dexmedetomidine With Bupivacaine On The Duration Of Sensory And Motor Block In Abdominal And Lower Limb Surgeries- A Prospective Randomised Double Blinded Study

BACKGROUND: The purpose of this study is to compare the duration of sensory and motor block in elective lower limb and abdominal procedures following intrathecal administration of bupivacaine along with adjuvants either clonidine or dexmedetomidine. METHODS: A prospective randomised double blinded study. 120 study participants were randomly allocated to three groups-Group A was given 12.5 mg of hyperbaric bupivacaine, Group B was given 3 mcg dexmedetomidine along with 12.5 mg hyperbaric bupivacaine and Group C was given 30 mcg of clonidine along with hyperbaric bupivacaine. The duration of sensory and motor block was recorded. RESULTS: Group B and C study participants showed significantly longer duration of sensory and motor block when compared to Group A. The mean duration of sensory block in Group A was 92.5 minutes, Group B 124.5 minutes Group C (119.4 minutes) (A vs B, A vs C p<0.001). The mean duration of motor block in group A 149.1 min, group B 252.5 min, Group C 217 min (A vs B, A vs C, B vs C P<0.001) CONCLUSION: By adding 3 mcg dexmedetomidine or 30 mcg clonidine to hyperbaric bupivacaine duration of sensory and motor block was significantly prolonged.

Comparative characteristics of the effectiveness of spinal anesthesia with intrathecal administration of bupivacaine and its combination with adjuvants

Comparative characteristics of the effectiveness of spinal anesthesia with intrathecal administration of bupivacaine and its combination with adjuvants

Comparison of the Dexmedetomidine and Sufentanil Added to Spinal Anesthesia with Bupivacaine for Hemodynamic Stability and Postoperative Analgesia in Elective Cesarean Section Surgery: A Single-Blinded Randomized Clinical Trial

Background: Hemodynamic instability, including hypotension and bradycardia, can occur due to spinal anesthesia by bupivacaine. However, it is possible to reduce the chance of hemodynamic changes by the reduction of the dose of bupivacaine and/or the addition of adjunctive agents. Objective: This study aimed to compare the effects of the addition of intrathecal dexmedetomidine and sufentanil to spinal anesthesia with bupivacaine in elective cesarean section (CS). Methods: This prospective single-blinded randomized clinical trial with parallel groups was performed on 60 pregnant women who were candidates for elective CS in Imam Reza Hospital in Kermanshah, Iran. In addition to receiving 10 mg of hyperbaric bupivacaine 0.5%, they were randomly divided into two groups to receive intrathecal sufentanil 5 μg (30 cases) or dexmedetomidine 5 μg (30 cases). Changes in blood pressure, heart rate, and occurrence of side effects (e.g., nausea, vomiting, headache, and shivering) were recorded within 1 h after the injections. Moreover, the postoperative analgesia rate and duration (using a visual analog scale [VAS]) were recorded within the first 24 h after the completion of the CS. Headache severity (using a VAS) was also measured during the first week after CS. Results: Patients declared their satisfaction with analgesia after surgery. No significant difference was found between the two groups in terms of heart rate and systolic and diastolic blood pressure changes during the first 60 min. Similarly, no significant difference was observed between the two groups in terms of the severity of incision pain in the first 24 h after CS surgery. On days 3, 4, and 5, none of the patients in the sufentanil and bupivacaine group had headaches (VAS=0), but patients in the dexmedetomidine and bupivacaine group had some degree of headache (P=0.040). Conclusions: Based on the results, intrathecal administration of bupivacaine with either sufentanil or dexmedetomidine in CS did not have significantly different effects, except for slightly more severe headaches in the dexmedetomidine group. Therefore, no superiority of one drug over the other was observed for intrathecal administration with bupivacaine in CS.

Analgesic Efficacy of Intrathecal Bupivacaine with or without Morphine in Lower Limb Orthopedic Surgery. A Comparative Study

Background: Lower limb orthopaedic surgeries are commonly associated with moderate to severe postoperative pain. Adequate pain relief is essential for patients undergoing such procedures, as uncontrolled pain can lead to delayed recovery, prolonged hospitalization, and increased morbidity. Intrathecal administration of bupivacaine, a long-acting local anesthetic, has been shown to provide effective analgesia after lower limb orthopaedic surgery. However, the duration of analgesia with bupivacaine alone is limited, and the addition of an opioid, such as morphine, can prolong the duration of analgesia. Objective: The objective of this study was to document the comparative effect of adding morphine to intrathecal bupivacaine or only intrathecal bupivacaine for lower limb trauma orthopedic surgeries in terms of onset of action, duration of analgesia, pain severity, and side effects. Methods: This was a comparative longitudinal study design conducted at the Orthopaedic Unit of the Tamale Teaching Hospital. A simple random sampling technique was used to recruit 60 patients. A standard structured questionnaire was also used to collect data on the socio-demographics, and clinical features of patients, drug used,side effects and severity of pain at 24,48 and 72 hrs after surgery. Results: Co-administration of intrathecal bupivacaine with morphine produced good and long-lasting postoperative analgesia with a mean time of 1004.25 ± 310.43 minutes, whiles using only bupivacaine produced shorter postoperative analgesia with a mean time of 294.75 ± 195.53 minutes. The p-value p values of p = 0.635 and p = 0.689 respectively. Conclusion: The study revealed that co-administration of intrathecal bupivacaine with morphine emerged as a better option for postoperative pain management after lower limb orthopedic surgeries as compared to administering only bupivacaine regarding the duration of analgesia. Milder side effects like pruritus, nausea, and vomiting were seen in group B than in group A and were promptly well managed to the patient’s satisfaction.

Evaluation and control of correction of volemic status using estimated continuous cardiac output technology for elective hernioplasty in obese patients

The objective. To substantiate the use of the Estimated Continuous Cardiac Output technology for the assessment and correction of the volemic status in obese patients during routine hernia repair of the anterior abdominal wall under spinal anesthesia. Subjects and methods. The study included 40 patients who underwent hernia repair of the anterior abdominal wall under spinal anesthesia. Inclusion criteria: body mass index of more than 30–40 kg/m2, physical status according to ASA II or III, no history of indications of diabetes mellitus, myocardial infarction, stroke, malignant neoplasm. Exclusion criteria: refusal of the patient, contraindications to spinal anesthesia. The patients were randomly divided into 2 groups of 20 people. Patients of both groups were comparable in age, gender, and physical status. Group 1 patients underwent preoperative evaluation, as well as monitoring of the effectiveness of correction of volemic status using EsCCO technology. Intraoperative infusion therapy was prescribed to patients of group 2 based on the doctor’s experience, blood pressure, heart rate and formulas for calculating the infusion load. Statistical analysis of the data obtained was performed using MS Excel, Statistica 10. To test the hypothesis of the normality of the distribution of a random variable, the Shapiro-Wilk test was used. Under conditions of normal distribution of quantitative indicators, descriptive statistics were used for statistical data analysis: mean value (M); standard deviation (SD); 95% confidence interval of standard deviation (C1). The Student’s t-test was used to analyze the differences between quantitative characteristics. The differences were considered significant at p<0.05. Results. The greatest decrease in systolic blood pressure by 4 minutes (from 122.8 to 117.5 mm Hg, by 4.3%) was revealed among group 1A patients, by 2 minutes (from 120.6 to 115.4 mm Hg, by 4.3%) among group 2 patients by 4 minutes (from 123.4 to 107.2 mm Hg, by 13.1%) from spinal anesthesia. The most pronounced change in heart rate relative to baseline data among group 1A and group 1B patients was noted at 2 minutes after intrathecal administration of bupivacaine (from 72.4 to 76.2, by 5% and from 74.6 to 78.4, by 4.8%, respectively) with a gradual return to parameters that are close to the baseline, and among patients in group 2, a sharp jump in heart rate from 73.8 to 83.3 (by 11.4%) was noted at 2 minutes. Heart rate continued to increase and by 6 minutes reached an average of 86.0, which is 14% higher than the original value. In all three groups of the study, the greatest deviation from the baseline was found at 6 minutes after the administration of bupivacaine with a further gradual return to slightly larger parameters than the base[1]line. Significant changes in SI were detected at 6 minutes from the execution of the neuroaxial block among all patients of this study. For group 1A, they ranged from 3.89 to 5.25 l/min/m2 (by 27.6%), for group 1B patients from 3.88 to 5.1 l/min/m2 (by 23.9%) and for group 2 from 3.84 to 5.45 l/min/m2 (by 29.5%). Conclusion. The Estimated Continuous Cardiac Output technology can be effectively used to assess and correct the volemic status in obese patients when performing elective hernia repair of the anterior abdominal wall under spinal anesthesia.

Super refractory status epilepticus in a parturient with preeclampsia undergoing cesarean delivery under spinal anesthesia

Super refractory status epilepticus (SRSE) is a rare but serious neurological emergency. This case report aims to highlight the challenges faced during the diagnosis and management of SRSE in a 36-year-old preeclamptic patient taken for cesarean delivery under spinal anesthesia. The patient developed a seizure episode minutes after administration of intrathecal bupivacaine, necessitating administration of general anesthesia. Postoperatively, SRSE developed which did not respond to multiple anti-epileptics and thiopentone sodium infusion. Although the clinical picture and magnetic resonance imaging findings supported the diagnosis of posterior reversible encephalopathy syndrome, the role of intrathecal bupivacaine in causing SRSE could not be ruled out due to the temporal association of events. The patient had a prolonged and complicated hospital stay and despite a multimodal approach to the treatment, suffered neurological sequelae.

10: Efficacy of premixed versus sequential administration of fentanyl and bupivacaine in subarachnoid block for lower limb tibial surgeries: A randomised double blind clinical Study

Background and Aims:Opioids are most commonly used as adjuvants in subarachnoid block. The drug and its mode of administration affects the various block characteristics. Intrathecal administration of bupivacaine and fentanyl as premixed is compared to sequential administration in two separate syringes.Methods:Total eighty patients were randomly allocated into two groups of 40 each: Group M (Mixed) received premixed 0.5% heavy bupivacaine 2.5 ml (12.5 mg) and 0.5 ml (25µg ) of fentanyl in a single 5.0 ml syringe, Group S (Sequential) received 0.5 ml (25 microgram) of fentanyl in a 2.0 ml syringe followed by 0.5% heavy bupivacaine 2.5 ml (12.5 mg) in a 5.0 ml syringe. Double blinding was ensured in all the cases performed. The onset and duration of sensory and motor blockade and haemodynamic parameters were observed. Data analysis was done using MedCalc software.Results:The mean time for onset of sensory and motor block was less in group S (P<0.0001). The duration of sensory and motor block was prolonged in group S (P<0.0001). Patients in group M experienced more hypotension as compared to group S (P<0.05). Need for rescue analgesia was less in Group S in 24 hours (P<0.05).Conclusion:Administering fentanyl first followed by hyperbaric bupivacaine leads to an early onset and prolonged duration of sensory and motor block and better haemodynamic stability and less need of rescue analgesia in 24 hours.

Spinal Myoclonus – A rare complication of spinal anaesthesia

Spinal segmental myoclonus is a rare type of myoclonic disorder that may occur during spinal anaesthesia. A few cases of spinal myoclonus have been reported after administration of intrathecal bupivacaine. The exact cause and pathophysiology of spinal myoclonus is unknown. We report a case of a 28-year-old female who underwent caesarean section under spinal anaesthesia with 0.5% hyperbaric bupivacaine. Myoclonic movements appeared in the early postoperative period in the left lower limb. The myoclonus was acute and transient. The patient recovered completely without any neurological complications. After ruling out all the possible causes, spinal myoclonus diagnosis was made, and the patient was discharged on the 3rd postoperative day. Keywords: Spinal anaesthesia, Spinal myoclonus, Myoclonus

Comparing Duration of Analgesia after Intrathecal Administration of Opioids in Primary Paturients for Lower Segment Cesarean Section.

Background:A pain free post operative period is a boon to mother for caring the neonate. We compared injection butorphanol and fentanyl as an adjuvant to bupivacaine in primary parturients for LSCS (Lower Segment Caesarean Section) with respect to duration of analgesia.Aims and Objectives:To study the effect of butorphanol vs fentanyl on duration of analgesia when added to bupivacaine for LSCS amongst primi parturients and to observe the block characteristics as secondary outcome.Materials and Methods::Study was carried out in 90 patients divided equally into three groups which included 12mg(2 mL) of 0.5% hyperbaric bupivacaine with 0.5 mL NS, 12mg (2 mL) of 0.5% hyperbaric bupivacaine 25 μg butorphanol made upto 2.5 mL with NS and 12mg(2 mL) of 0.5% hyperbaric bupivacaine with 25μg fentanyl made upto 2.5mL with normal saline. All patients were observed for duration of analgesia. Also Heart Rate (HR), Systolic and Diastolic Blood Pressure (SBP, DBP), two segment regression time of sensory block, motor block were assessed. The results were compiled and statistically analyzed using Chi-square test for nonparametric data and ANOVA for parametric data.Results:Two segment sensory regression is significantly prolonged in group with intrathecal administration of Bupivacaine with Butorphanol (190.33±15.86) than Bupivacaine with Fentanyl (170.67±20.83) and Bupivacaine with Normal saline (150.33±16.91). Duration of effective post operative analgesia was 349.67, 591.87 and 468.00 min in Group I, Group II and Group III respectively. There was no significant difference in onset of sensory and motor blockage in all three groups. HR, SBP and DBP were comparable among the groups.Conclusions:Intrathecal bupivacaine with 25 μg butorphanol mixture was clinically better as it provided longer duration of analgesia along with prolonged sensory block when compared to intrathecal bupivacaine with 25μg fentanyl mixture in primary parturients for LSCS.

The Effect of Intravenous Dexmedetomidine Infusion on Subarachnoid Block with Bupivacaine in Inguinal Herniorrhaphies

Background: lumbar subarachnoid block is a technique which requires a small dose of heavy bupivacaine to provide rapid and reliable surgical anaesthesia. Duration of spinal anaesthesia may be prolonged by addition of opioids, clonidine, neostigmine, or vasoconstrictor agents to the local anesthetic drug for better post-op pain relief. This study is designed to investigate the effects of intravenous dexmedetomidine on the duration of sensory and motor blockade induced by intrathecal administration of bupivacaine, and its associated adverse events. Aims and Objectives: To assess the effect of Dexmedetomidine infusion on the duration of analgesia with spinal Bupivacaine for adult patients undergoing herniorrhaphy and to assess the incidence of intra operative side effects, if any. Subjects and Methods: This study was done under the department of Anaesthesiology, Govt. T. D. Medical College Hospital, Alappuzha, Kerala for a period of 8 months. A double blind prospective randomized control study was done.50 adults aged 20 to 60 years scheduled for herniorrhaphies were allocated into two study groups, named A and B using computer generated randomization. Results: The duration of analgesia compared and Post-operative pain was evaluated by Visual Analogue Scale. Duration of analgesia is the time taken from the administration of the drug to the time when the patient complains of pain of &gt; 50 in Visual Analogue Scale. The duration of analgesia was longest in patients received intravenous dexmedetomidine along with spinal bupivacaine. Side effect like respiratory depression not observed in either group. Conclusion: In conclusion, intravenous infusion of dexmedetomidine added to subarachnoid block with bupivacaine offered prolonged analgesia in adult patients undergoing herniorrhaphies, without increasing the incidence of adverse effects.

Effects of intrathecal bupivacaine on the NR2B/CaMKIIα/CREB signaling pathway in the rat lumbar spinal cord.

Neuraxial anesthesia produces an anesthetic-sparing, sedative effect. The mechanism underlying this effect potentially involves decreased spinal afferent input. However, the neurochemical mechanisms at the spinal level remain unknown. The N-methyl-D-aspartate receptor 2B subunit/calcium-calmodulin-dependent protein kinase II α/cAMP response element-binding protein (NR2B/CaMKIIα/CREB) signaling pathway serves an important role in regulating the transmittance of peripheral noxious stimulation to supraspinal regions in the process of nociception. The present study investigated the effects of intrathecal bupivacaine on the NR2B/CaMKIIα/CREB signaling pathway. Following catheterization, 36 male Sprague-Dawley rats were randomly assigned to a normal saline (NS) or bupivacaine treatment group, in which each rat intrathecally received 20 µl normal saline or 0.5% bupivacaine, respectively. The expression levels of NR2B, CaMKIIα/p-CaMKIIα, and CREB/phosphorylated (p)-CREB in the lumbar spinal cord were investigated by western blotting, reverse transcription-quantitative polymerase chain reaction and immunohistochemistry (IHC). Following bupivacaine treatment, western blot analysis demonstrated that the protein expression levels of NR2B, p-CaMKIIα, and p-CREB in the spinal cord were reduced by approximately 54, 56 and 33%, respectively, compared with NS control rats. Similar alterations in expression were observed by IHC analysis. Additionally, mRNA expression levels of NR2B, CaMKIIα, and CREB were also downregulated following the intrathecal administration of bupivacaine. Therefore, the sedative effect of subarachnoid blockade with bupivacaine possibly occurs through de-afferentation, which may reduce cortical arousal by downregulating the spinal NR2B/CaMKIIα/CREB pathway in vivo, however further investigation is required in order to verify this.

The Effects of Intrathecal Administration of Bupivacaine or Ropivacaine Following Administration of Propofol in Dogs Undergoing Ovariohysterectomy

The Effects of Intrathecal Administration of Bupivacaine or Ropivacaine Following Administration of Propofol in Dogs Undergoing Ovariohysterectomy

A Case of Chemical Meningitis Induced by Intrathecal Bupivacaine Injection

Background: Iatrogenic meningitis after spinal anesthesia is a rare condition. Most cases of iatrogenic meningitis have a bacterial etiology; however, there are a few reports of chemical meningitis associated with intrathecal administration of bupivacaine. Case Report: A 74-year-old man underwent cystoscopy, with anesthesia by intrathecal bupivacaine hydrochloride injection. Two hours post-procedurally, he complained of a severe headache and his mental status subsequently deteriorated from alertness to confusion. Cerebrospinal fluid examination on the day of admission showed an increase in cell count (841/mm 3 ; polymorphonuclear 78%: mononuclear 10%) and total protein (460 mg/dL). His clinical findings and laboratory abnormalities were consistent with the diagnosis of bupivacaine-induced chemical meningitis, rather than the bacterial meningitis. Conclusion: We report a case of chemical meningitis after spinal anesthesia with bupivacaine. Differential diagnosis should include chemical meningitis in cases of meningitis after spinal anesthesia. J Neurocrit Care 2014;7(2):122-124

A Case of Chemical Meningitis Induced by Intrathecal Bupivacaine Injection

Background: Iatrogenic meningitis after spinal anesthesia is a rare condition. Most cases of iatrogenic meningitis have a bacterial etiology; however, there are a few reports of chemical meningitis associated with intrathecal administration of bupivacaine. Case Report: A 74-year-old man underwent cystoscopy, with anesthesia by intrathecal bupivacaine hydrochloride injection. Two hours post-procedurally, he complained of a severe headache and his mental status subsequently deteriorated from alertness to confusion. Cerebrospinal fluid examination on the day of admission showed an increase in cell count (841/mm3; polymorphonuclear 78%: mononuclear 10%) and total protein (460 mg/dL). His clinical findings and laboratory abnormalities were consistent with the diagnosis of bupivacaine-induced chemical meningitis, rather than the bacterial meningitis. Conclusion: We report a case of chemical meningitis after spinal anesthesia with bupivacaine. Differential diagnosis should include chemical meningitis in cases of meningitis after spinal anesthesia. Key Words: Meningitis; Spinal anesthesia; Bupivacaine

Effects of opium addiction on level of sensory block in spinal anesthesia with bupivacaine for lower abdomen and limb surgery: a case-control study.

Background:In clinical practice, the level of sensory block in spinal anesthesia in opium abusers is lower than that in non-abusers because of adaptive changes caused by opium use.Objectives:The aim of this study was to investigate the level of sensory block resulting from the intrathecal administration of 0.5% bupivacaine in opium abuser patients undergoing lower extremity and lower abdominal surgeries.Patients and Methods:A total of 100 patients who were candidates of elective lower extremity orthopedic and lower abdominal surgeries were recruited and assigned to two groups based on their history of opium addiction (Case or control). Both groups underwent the same anesthesia procedure and pinprick test was used to assess the level of anesthesia.Results:No statistically significant difference was observed between groups regarding age, duration of the surgery, and type of surgery. The frequency of addiction was higher in males than in females. The level of sensory block at three minutes was significantly lower in the opium abuser group (P = 0.006). The mean time to achieve T10 sensory block was 10.33 ± 5.79 minutes in the opium abusers and 6.89 ± 3.88 minutes in the controls (P = 0.001). The level of the highest sensory block was lower in the opium abuser group (P = 0.002).Conclusions:The findings of this study suggested that after induction of spinal anesthesia with intrathecal administration of bupivacaine, chronic opium abusers would have a lower level of sensory block in comparison with patients without a history of opium abuse.

English

INTRODUCTION: Central neuraxial blocks with local anaesthetics are popular techniques of anaesthesia which have been extensively used for lower abdominal surgery. Subarachnoid block is a simple technique which requires a small dose of local anaesthetic to provide rapid and reliable surgical anaesthesia and minimal risk of drug toxicity. Duration of spinal anaesthesia may be prolonged by addition of opioids, clonidine, neostigmine, or vasoconstrictor agents to the local anesthetic drug for better post-op pain relief. Intrathecal addition of a low dose of α2-agonist like clonidine or dexmedetomidine results in significant prolongation of the duration of the sensory and motor blockade induced by hyperbaric bupivacaine. This study is designed to investigate the effects of intravenous dexmedetomidine on the duration of sensory and motor blockade induced by intrathecal administration of bupivacaine, and its associated adverse events. AIMS AND OBJEVCTIVES: To determine effect of intravenous Dexmedetomidine on the duration of analgesia with spinal Bupivacaine for adult patients undergoing herniorrhaphy and to assess the incidence of intra operative side effects, if any. STUDY SETTING: This study was done under the department of Anaesthesiology, Azeezia Medical College from March 2013 to October 2013. STUDY DESIGN: A double blind prospective randomized control study was done.50 adults aged 20 to 60 years scheduled for herniorrhaphies were allocated into two study groups, named A and B using computer generated randomization. INTERPRETATIONS AND CONCLUSION: The duration of analgesia of subarachnoid block with heavy 0.5% bupivacaine with intravenous infusion of saline and dexmedetomidine were compared. Post-operative pain was evaluated by Visual Analogue Scale. Duration of analgesia is the time taken from the administration of the drug to the time when the patient complains of pain of > 50 in Visual Analogue Scale. The duration of analgesia was longest in patients received intravenous dexmedetomidine along with spinal bupivacaine. There were no significant differences between the groups for the time of onset of sensory blockade and time to achieve maximum sensory blockade. Incidence of hypotension and bradycardia were not clinically and statistically significant in both groups. Incidence of postoperative nausea and vomiting was also similar in both the groups. Side effect like respiratory depression not observed in either group. In conclusion, Intravenous infusion of dexmedetomidine added to subarachnoid block with bupivacaine offered prolonged analgesia in adult patients undergoing herniorrhaphies, without increasing the

CASE REPORT - -Combined General and Spinal Anesthesia for Lumbar decompression in an Opioid-intolerant Patient: Intra-operative Administration of Intrathecal Bupivacaine via the Surgical Incision

We illustrate repeat dosing of spinal anesthesia as a means to avoid opioids during lumbar surgery for a patient intolerant of opioids. A patient required redo lumbar surgery but had a marked history of nausea, vomiting and retching in response to opioids. A propofol-based anesthetic was supplemented with intravenous ketamine and intrathecal bupivacaine. The first dose of bupivacaine receded during the lengthy surgical procedure but was supplemented by means of a 25-gauge pencil-point needle passed through the exposed dura. Postoperatively, there was no spinal fluid leak, no headache, and no nausea. Supplementation of intrathecal anesthesia under direct dural vision during lengthy lumbar surgery is facile, can help to obviate a need for opioids, and can aid in avoidance of postoperative nausea and vomiting.

Pitfalls in Chronobiology

The duration of analgesia from epidural administration of local anesthetics to parturients has been shown to follow a rhythmic pattern according to the time of drug administration. We studied whether there was a similar pattern after intrathecal administration of bupivacaine in parturients. In the course of the analysis, we came to believe that some data points coincident with provider shift changes were influenced by nonbiological, health care system factors, thus incorrectly suggesting a periodic signal in duration of labor analgesia. We developed graphical and analytical tools to help assess the influence of individual points on the chronobiological analysis. Women with singleton term pregnancies in vertex presentation, cervical dilation 3 to 5 cm, pain score >50 mm (of 100 mm), and requesting labor analgesia were enrolled in this study. Patients received 2.5 mg of intrathecal bupivacaine in 2 mL using a combined spinal-epidural technique. Analgesia duration was the time from intrathecal injection until the first request for additional analgesia. The duration of analgesia was analyzed by visual inspection of the data, application of smoothing functions (Supersmoother; LOWESS and LOESS [locally weighted scatterplot smoothing functions]), analysis of variance, Cosinor (Chronos-Fit), Excel, and NONMEM (nonlinear mixed effect modeling). Confidence intervals (CIs) were determined by bootstrap analysis (1000 replications with replacement) using PLT Tools. Eighty-two women were included in the study. Examination of the raw data using 3 smoothing functions revealed a bimodal pattern, with a peak at approximately 0630 and a subsequent peak in the afternoon or evening, depending on the smoother. Analysis of variance did not identify any statistically significant difference between the duration of analgesia when intrathecal injection was given from midnight to 0600 compared with the duration of analgesia after intrathecal injection at other times. Chronos-Fit, Excel, and NONMEM produced identical results, with a mean duration of analgesia of 38.4 minutes (95% CI: 35.4-41.6 minutes), an 8-hour periodic waveform with an amplitude of 5.8 minutes (95% CI: 2.1-10.7 minutes), and a phase offset of 6.5 hours (95% CI: 5.4-8.0 hours) relative to midnight. The 8-hour periodic model did not reach statistical significance in 40% of bootstrap analyses, implying that statistical significance of the 8-hour periodic model was dependent on a subset of the data. Two data points before the change of shift at 0700 contributed most strongly to the statistical significance of the periodic waveform. Without these data points, there was no evidence of an 8-hour periodic waveform for intrathecal bupivacaine analgesia. Chronobiology includes the influence of external daily rhythms in the environment (e.g., nursing shifts) as well as human biological rhythms. We were able to distinguish the influence of an external rhythm by combining several novel analyses: (1) graphical presentation superimposing the raw data, external rhythms (e.g., nursing and anesthesia provider shifts), and smoothing functions; (2) graphical display of the contribution of each data point to the statistical significance; and (3) bootstrap analysis to identify whether the statistical significance was highly dependent on a data subset. These approaches suggested that 2 data points were likely artifacts of the change in nursing and anesthesia shifts. When these points were removed, there was no suggestion of biological rhythm in the duration of intrathecal bupivacaine analgesia.

Recurrent spinal myoclonus after two episodes of spinal anesthesia at a 1-year interval -A case report-

Spinal myoclonus is an unusual, self-limiting, adverse event that may occur during spinal anesthesia. The exact cause and underlying biochemical mechanism of spinal myoclonus remain unclear. A few cases of spinal myoclonus have been reported after administration of intrathecal bupivacaine. We report a case in which spinal myoclonus recurred after two episodes of spinal anesthesia with bupivacaine at a 1-year interval in a 35-year-old woman. The myoclonus was acute and transient. The patient recovered completely, with no neurologic sequelae.