Current issues in spinal anesthesia.

Combination spinal analgesic chemotherapy: a systematic review.

We sought to identify factors that are associated with hypotension after the induction of spinal anesthesia (SpA) by using an anesthesia information management system. Hypotension was defined as a decrease of mean arterial blood pressure of more than 30% within a 10-min interval, and relevance was defined as a therapeutic intervention with fluids or pressors within 20 min. From January 1, 1997, to August 5, 2000, data sets from 3315 patients receiving SpA were recorded on-line by using the automatic anesthesia record keeping system NarkoData. Hypotension meeting the predefined criteria occurred in 166 (5.4%) patients. Twenty-nine patient-, surgery-, and anesthesia-related variables were studied by using univariate analysis for a possible association with the occurrence of hypotension after SpA. Logistic regression with a forward stepwise algorithm was performed to identify independent variables (P < 0.05). The discriminative power of the logistic regression model was checked with a receiver operating characteristic curve. Calibration was tested with the Hosmer-Lemeshow goodness-of-fit test. The univariate analysis identified the following variables to be associated with hypotension after SpA: age, weight, height, body mass index, amount of plain bupivacaine 0.5% used for SpA, amount of colloid infusion before puncture, chronic alcohol consumption, ASA physical status, history of hypertension, urgency of surgery, surgical department, sensory block height of anesthesia, and frequency of puncture. In the multivariate analysis, independent factors for relevant hypotension after SpA consisted of three patient-related variables ("chronic alcohol consumption," odds ratio [OR] = 3.05; "history of hypertension," OR = 2.21; and the metric variable "body mass index," OR = 1.08) and two anesthesia-related variables ("sensory block height," OR = 2.32; and "urgency of surgery," OR = 2.84). The area of 0.68 (95% confidence interval, 0.63-0.72) below the receiver operating characteristic curve was significantly greater than 0.5 (P < 0.01). The goodness-of-fit test showed a good calibration of the model (H = 4.3, df = 7, P = 0.7; C = 7.3, df = 8, P = 0.51). This study contributes to the identification of patients with a high risk for hypotension after SpA induction, with the risk increasing two- or threefold with each additional risk factor. By using automated data collection, 5 (chronic alcohol consumption, history of hypertension, body mass index, sensory block height, and urgency of surgery) of 29 variables could be detected as having an association with hypotension after spinal anesthesia induction. The knowledge of these risk factors should be useful in increasing vigilance in those patients most at risk for hypotension, in allowing a more timely therapeutic intervention, or even in suggesting the use of alternative methods of spinal anesthesia, such as titrated continuous or small-dose spinal anesthesia.

Continuous Spinal Anesthesia with Invasive Hemodynamic Monitoring for Surgical Repair of the Hip in Two Patients with Severe Aortic Stenosis

In Response: We appreciate Dr. Colclough's thoughtful letter about our paper comparing spinal and epidural anesthesia for cesarean section. However, we disagree with him on several of the issues he raises. Our data and that of other investigators (cited in our paper) demonstrate that spinal anesthesia for cesarean section is faster to perform and has fewer complications, and that patients may experience less discomfort intraoperatively. Dr. Colclough states that many anesthesiologists can place a needle in the epidural space more quickly than they can place a small-gauge spinal needle into the cerebrospinal fluid. We doubt this is the case and are unaware of any research supporting this statement. However, even if an epidural needle can be properly positioned faster than a spinal needle, the rest of the spinal anesthetic procedure can be performed much more quickly. The mechanics of performing a safe epidural block (even when the initial dose is administered through the needle) include giving a test dose, waiting 3 to 4 min to observe the patient before further dosing, fractionating the local anesthetic dose over several minutes, and then threading the catheter. Administering a bolus of even a relatively nontoxic local anesthetic such as chloroprocaine is inappropriate, except in extreme emergencies. Furthermore, in our experience, 20 mL of chloroprocaine does not always produce an adequate block, necessitating further dosing and delay. We agree with Dr. Colclough that continuous epidural anesthesia is inherently more versatile than spinal anesthesia, but believe that the "one-shot" epidural technique he describes lacks versatility until the catheter has been tested and confirmed to be correctly sited. This would require injection of a second test dose via the catheter, causing additional delay. Perhaps the most compelling argument favoring spinal anesthesia is the decreased incidence of potential complications. When giving local anesthetics into the epidural space, drug may be injected into either the intravascular or intrathecal space with disastrous results. Even when correctly deposited in the epidural space, maldistribution of drug may leave some nerve roots unblocked, causing a failed block. In summary, we believe our data support our conclusions. The increasing use of spinal anesthesia for cesarean section in major obstetric centers throughout the world similarly reflects the experience that failure and complications occur less frequently than with epidural anesthesia. We encourage others to critically review their practice. We especially invite practitioners in nonteaching centers to conduct similar studies to see whether the trends we report hold true in the general community. Edward T. Riley, MD Sheila E. Cohen, MB, ChB Alex Macario, MD Emily F. Ratner, MD Department of Anesthesia, Stanford University School of Medicine, Stanford, CA 94305-5117

Anesthetic management of a parturient with olivopontocerebellar degeneration.

Topicality. Using generally accepted methods of calculating doses of local anesthetic during spinal anesthesia, the efficiency and safety of anesthesia are not always sufficient.&#x0D; The aim of our study was to determine the optimal dose of local anesthetic according to the height of the patient gradation method for unilateral and bilateral spinal anesthesia during orthopedic and traumatological operations on the lower extremities. Determine the advantages and disadvantages of both methods of analgesia.&#x0D; Materials and methods: Our study is based on an examination of 52 patients of I-II degrees of surgical risk according to ASA, divided into two groups. The first group (control) included 25 patients who underwent bilateral spinal anesthesia, the second group included 27 patients who underwent unilateral spinal anesthesia during orthopedic and traumatological operations on the lower extremities. Spinal anesthesia was performed with a hyperbaric solution of 0.5% bupivacaine, with the anesthetic dosing algorithm developed by us.&#x0D; Results: When evaluating the effectiveness of the performed spinal anesthesia, the duration of sensory and motor blocks and the level of development of sensory blockade by dermatomes in both study groups were determined. In the 1st group, the sensory block was 252.2±74.32 min., the motor block was 198.2±59 min. In the II group, the sensory block was 189.25±34.27 min., the motor block was 154.07±28.59 min. When determining the frequency of cardiovascular complications, dynamics of indicators in mean arterial pressure (MAP) and heart rate (HR) were determined before surgery, after 5 min., 30 min., 1 h., 2 h., 3 h., 5 h., 7 h., 9 h. It was found that the decrease in MAP and heart rate prevailed in the first group during the study. The volume of crystalloid infusion in the first research group was 2042±663.9 ml, and in the second group – 1666.66±635.49 ml. Laboratory diagnostic methods were used in order to determine dynamics of indicators in the basic metabolism and hormonal background during the occurrence of pain syndrome in patients and the effect of the dose of local anesthetic on the speed and level of changes in these parameters. For this purpose, changes in blood glucose, lactate and blood cortisol were determined before surgery, 3 hours, 6 hours and 9 hours of anesthesia course.&#x0D; Conclusions: 1. Gradational dosing of local anesthetic for unilateral and bilateral spinal anesthesia according to height ensures the necessary effectiveness of analgesia. 2. Reducing the dose of anesthetic during unilateral spinal anesthesia increases the safety of anesthesia and causes less side effects. 3. The duration and level of sensory blockade of unilateral spinal anesthesia is significantly reduced when using a reduced dose of local anesthetic in comparison with bilateral.

Epidural Anesthesia and Pulmonary Function in a Patient with Amyotrophic Lateral Sclerosis

Combined spinal-epidural anaesthesia (CSEA) using a needle-through-needle technique is currently widely used. However, successful epidural needle placement does not mean a successful spinal needle placement during CSEA. Whether ultrasound assistance could increase the first-pass success rate of spinal needle placement for CSEA remains unknown. The aim of this study was to investigate if ultrasound assistance could increase the first-pass success rate of spinal needle placement through the epidural needle during CSEA performed by experienced anaesthesiologists in patients undergoing caesarean section. A prospective, randomised, double-blind study. Single centre, Department of Anaesthesiology, Shengjing Hospital, China Medical University, China, from June 2019 to September 2019. A total of 185 patients (aged 24 years to 52 years, American Society of Anesthesiologists grade (ASA) II-III, 38 to 40 weeks gestation) scheduled to undergo elective caesarean section under CSEA were enrolled. The patients were randomised to either an ultrasound group (patients received a preprocedural ultrasound scan, and the puncture site was identified by ultrasound imaging) and a palpation group (patients received a sham procedural ultrasound scan, and the puncture site was identified by conventional palpation). The primary outcome measure was the first-pass success rate for spinal needle placement through the epidural needle. Secondary outcome measures were total duration of CSEA, time required for successful epidural needle and spinal needle placement, number of epidural needle redirections and complications. Preprocedural ultrasound imaging significantly increased the first-pass success rate of spinal needle placement through the epidural needle compared with conventional palpation (93.8 vs. 68.8%, P < 0.001). Preprocedural ultrasound imaging also decreased the total duration of CSEA (186.9 ± 37.1 vs. 213 ± 60.4 s, P = 0.0015) and the time required for successful spinal needle placement (78.3 ± 22.9 vs. 100.1 ± 53.7 s, P < 0.01) compared with conventional palpation. Fewer patients in the ultrasound group needed epidural needle redirections during the spinal needle placement procedure than in the palpation group (four patients vs. 20 patients, P < 0.01). For experienced anaesthesiologists, preprocedural ultrasound imaging significantly increased the first-pass success rate of spinal needle placement through the epidural needle for obstetric patients undergoing caesarean section under CSEA. chictr.org.cn, identifier: ChiCTR1900024132.

Ropivacaine is a long-acting amide local anaesthetic agent and first produced as a pure enantiomer. It produces effects similar to other local anaesthetics via reversible inhibition of sodium ion influx in nerve fibres. Ropivacaine is less lipophilic than bupivacaine and is less likely to penetrate large myelinated motor fibres, resulting in a relatively reduced motor blockade. Thus, ropivacaine has a greater degree of motor sensory differentiation, which could be useful when motor blockade is undesirable. The reduced lipophilicity is also associated with decreased potential for central nervous system toxicity and cardiotoxicity. The drug displays linear and dose proportional pharmacokinetics (up to 80 mg administered intravenously). It is metabolised extensively in the liver and excreted in urine. The present article details the clinical applications of ropivacaine and its current place as a local anaesthetic in the group.

The purpose of this study is to determine if spectral analysis of beat-to-beat heart rate variability will provide important data on autonomic nervous system function during either spinal or epidural anesthesia that is not apparent from the monitoring of mean heart rate and blood pressure. Twelve ASA I patients presenting for elective cesarean delivery (7 epidural and 5 spinal anesthetics) were prospectively selected for study. Control and postblock 10-minute segments of instantaneous heart rates were analyzed for each patient. The total spectral power (Ps, 0.02-0.5 Hz), low frequency spectral power (PLF, 0.02-0.12 Hz), and high frequency spectral power (PHF, 0.12-0.5 Hz) were calculated for each data segment. The complexity of the heart rate time series was estimated by calculating the approximate entropy. Neither spinal or epidural anesthesia had any effect on heart rate or blood pressure. Both spinal and epidural anesthesia did produce a significant decrease in PS, PLF, and PHF. Although there were significant decreases in both the PLF and PHF, there was no change in the PLF/PHF ratio. There was a significant reduction in approximate entropy with spinal and epidural anesthesia, indicating a decrease in complexity of the heart rate dynamics. These data suggest that autonomic tone decreased with spinal and epidural anesthesia but the sympathetic-parasympathetic balance (expressed as PLF/PHF) did not change. Spectral measures, as well as approximate entropy, provide an independent evaluation of the integrity of the autonomic nervous system and cardiovascular control mechanisms that cannot be discerned from mean heart rate and blood pressure.

We compared general, epidural, and spinal anesthesia for outpatient knee arthroscopy (excluding anterior cruciate ligament repairs). Forty-eight patients (ASA physical status I-III) were randomized to receive either propofol-nitrous oxide general anesthesia with a laryngeal mask airway with anesthetic depth titrated to a bispectral index level of 40-60, 15-20 mL of 3% 2-chloroprocaine epidural, or 75 mg of subarachnoid procaine with 20 microg fentanyl. All patients were premedicated with <0.035 mg/kg midazolam and <1 microg/kg fentanyl and received intraarticular bupivacaine and 15-30 mg of IV ketorolac during the procedure. Recovery times, operating room turnover times, and patient satisfaction were recorded by an observer using an objective scale for recovery assessment and a verbal rating scale for satisfaction. Statistical analysis was performed with analysis of variance and chi(2). Postanesthesia care unit discharge times for the general and epidural groups were similar (general = 104+/-31 min, epidural = 92+/-18 min), whereas the spinal group had a longer recovery time (146+/-52 min) (P = 0.0003). Patient satisfaction was equally good in all three groups (P = 0.34). Room turnover times did not differ among groups (P = 0.16). There were no anesthetic failures or serious adverse events in any group. Pruritus was more frequent in the spinal group (7 of 16 required treatment) than in the general or epidural groups (no pruritus) (P<0.001). We conclude that epidural anesthesia with 2-chloroprocaine provides comparable recovery and discharge times to general anesthesia provided with propofol and nitrous oxide. Spinal anesthesia with procaine and fentanyl is an effective alternative and is associated with a longer discharge time and increased side effects. For outpatient knee arthroscopy, anesthesia can be provided adequately with regional or general anesthesia. Epidural and general anesthesia provide equal recovery times and patient satisfaction, whereas spinal anesthesia may prolong recovery and have increased side effects. The choice of anesthesia may depend primarily on the patient's interest in being alert or asleep during the procedure.

Pilot Randomized Controlled Trial of Spinal Versus General Anesthesia for Hip Fracture Surgery.

Effective plexus anaesthesia in a patient with Ehlers–Danlos syndrome type III

Inguinal hernia repair is one of the most common operations performed in General Surgery accounting for about 10-15% of all surgeries. Inguinal hernia repair can be done under local, spinal or general anaesthesia. Although specialized hernia centres routinely use local anaesthesia for uncomplicated open inguinal hernia repair, very few surgeons adopt this technique, and prefer performing surgery under spinal or general anaesthesia. We compared the short-term outcomes following open inguinal hernia mesh repair under local, spinal and general anaesthesia in our hospital. (1) To compare the post-operative pain scores among the three groups. (2) To compare the duration of surgery in minutes, the duration of analgesia, analgesic requirement, the time of return to normal activity such as walking, the time of initiation of diet, and the time of voiding after the surgery. Also to compare any complications, such as urinary retention, need for catheterization, nausea and/or emesis, and the length of hospital stay. (3) To observe the impact on health-related quality of life according to EuroQol and patient satisfaction and acceptance of the type of anaesthesia for the procedure. A single centre non-randomised, prospective, observational study was performed in 135 patients undergoing inguinal hernia repair under local (LA), spinal (SA) or general anaesthesia (GA), with 45 patients in each arm, over the span of one year. After approval from the Ethical Committee, and proper informed consent, patients above 18years of age who were to undergo uncomplicated open inguinal hernioplasty were recruited for the study. Lichtensteins tension-free hernioplasty was performed in all cases. The duration of the procedure was calculated from the time of induction or infiltration of local or spinal anaesthesia, till the end of dressing, or extubation in case of general anaesthesia. The duration of analgesia was calculated from the end of the procedure to the feeling of first pain as recorded in the questionnaire. A standard postoperative protocol was employed to determine the pain scores for the first 7days and also to compare the short-term outcomes i.e., duration of analgesia, return to normal activity, complications, post-operative nausea and emesis, analgesic requirement, urinary retention, length of hospital stay, health-related quality of life and patient satisfaction and acceptance were recorded according to standard proforma and EuroQol questionnaire. All the statistical analysis was carried out by SPSS version 16.0. The mean pain scores were lower in the LA group as compared to SA and GA groups from POD-1 to POD-6 (p < 0.001). However, the values from the 7th post-operative days were similar in all three groups and statistically insignificant (p = 0.09). The outcomes such as duration of analgesia, return to activity such as walking, time of first meal and time of discharge from the hospital were all better in the LA group (p < 0.001). The results concerning nausea, vomiting, analgesic use and urinary retention all favour LA. No difference was found among the three groups concerning overall satisfaction and quality of life. In a general surgical setting, we found that local anaesthesia is well tolerated and associated with significantly lower pain scores in the immediate post-operative period and also requires less analgesic use when compared with general and spinal anaesthesia. Patients in the LA group can resume basic activities such as walking, voiding, and initiating diet almost immediately after the procedure and there were no incidences of retention of urine, which was a significant advantage over the other two types of anaesthesia. Patients who were graded as ASA 4 and 5, who were unfit for general anaesthesia, were able to undergo the surgery under local anaesthesia with no postoperative complications. Moreover, the complications and risks of spinal and general anaesthesia are avoided without compromising the quality of surgery and its outcomes. The duration of the surgery as well as hospital stay is significantly less in patients undergoing surgery under local anaesthesia and most cases can be done as a daycare procedure, which is significantly advantageous, especially in low-income settings, with no difference in the health-related quality of life or patient satisfaction and acceptance.

Epidural, spinal, and combined spinal epidural anesthesia for ambulatory surgery