Intrathecal catheter use after accidental dural puncture in obstetric patients: literature review and clinical management recommendations.

If an accidental dural puncture occurs, one option is to insert a catheter and use it as an intrathecal catheter. This avoids the need for a further injection and can rapidly provide labour analgesia and anaesthesia for caesarean section. However, there are no recommendations for managing intrathecal catheters and, therefore, significant variation in clinical practice exists. Mismanagement of the intrathecal catheter can lead to increased motor block, high spinal anaesthesia, drug error, hypotension and fetal bradycardia. Care must be taken with an intrathecal catheter to adhere to strict aseptic technique, meticulous labelling, cautious administration of medications and good communication with the patient and other staff. Every institution considering the use of intrathecal catheters should establish a protocol. For labour analgesia, we recommend the use of dilute local anaesthetic agents and opioids. For caesarean section anaesthesia, gradual titration to the level of the fourth thoracic dermatome, with full monitoring, in a facility equipped to manage complications, should be performed using local anaesthetics combined with lipophilic opioids and morphine or diamorphine. Although evidence of the presence and duration of intrathecal catheters on the development of post-dural puncture headache and need for epidural blood patch is limited, we suggest considering leaving the intrathecal catheter in for 24 hours to reduce the chance of developing a post-dural puncture headache while maintaining precautions to avoid drug error and cerebrospinal fluid leakage. Injection of sterile normal saline into the intrathecal catheter may reduce post-dural puncture headache. The level of evidence for these recommendations was low.

Feasibility study of a force-sensing resistor device for landmark detection for neuraxial procedures and anesthesiologists' impact on device improvement.

The standard of care for neuraxial procedures is landmark palpation to determine the site of placement. This research study aimed to test the primary feasibility of VerTouch™, a force-sensing resistor device, to identify landmarks for the initiation of neuraxial procedures. Patients were recruited at the time of labour epidural, or when consenting for spinal anaesthesia for caesarean delivery at a single centre. The clinical team used the device to create a pressure map image of the bony spine. If they felt confident, they used the device guide to make a mark on the patient's back. If the mark was used, total insertions and redirections, combined as passes, of the needle during the procedure were counted for secondary outcome analysis. A total of 101 parturients were recruited, and the provider felt confident making a mark based on the imaging in 96.9% of cases. Device success (completion using the mark and ≤4 total passes) occurred in 91.4% of cases. This feasibility study showed that the primary outcome, the provider using the device to make a mark, was successful. In addition, based on comparing passes with historical data, the Vertouch™ device showed promise for future use to minimise needle manipulation in neuraxial procedures.

Efficacy of the Epidural Positioning Device® in optimizing the acoustic target window for neuraxial needle placement in term pregnancy.

BACKGROUND: Neuraxial anesthesia can be challenging in obstetric patients due to the gravid uterus interfering with patient positioning. Ultrasound is commonly used in obstetric anesthesia to facilitate neuraxial needle placement. Some positioning maneuvers facilitate the ultrasound visualization of structures and the placement of neuraxial needles, but the Epidural Positioning Device (EPD) has yet to be evaluated. OBJECTIVES: Our goal was to evaluate whether the use of the EPD increased the acoustic target window in the lumbar area of pregnant patients. We hypothesized that the application of the EPD would increase the measured lengths of the paravertebral longitudinal ligament (PLL), the interlaminar distance (ILD) and the ligamentum flavum (LF). METHODS: Lumbar ultrasonography was performed on 29 pregnant women having an elective cesarean delivery. Two anesthesiologists independently scanned the L3-4 right paramedian space, using a curvilinear ultrasound transducer, in two positions for each patient: traditional sitting with lumbar flexion and sitting with use of the EPD for lumbar flexion. The PLL, ILD and LF lengths were measured using the ultrasound caliper software and recorded, with the anesthesiologists blinded to the results. Patients were asked to rate their comfort in both positions. RESULTS: There were no significant differences between the measured lengths of the PLL, ILD and LF in the two positions. Patient comfort was significantly higher with use of the EPD (OR 10, 95% CI 2.4 to 88). CONCLUSION: Although the application of an EPD did not improve the paramedian acoustic target area in term parturients, greater patient comfort might facilitate needle placement.

Impact of spinal needle design and approach to postdural puncture headache and spinal anesthesia failure in obstetrics.

BACKGROUND: Concern has been raised that Sprotte needles predispose to spinal anes-thesia failure. Nevertheless, these needles are associated with a low incidence of postdural puncture headache. The impact of the paramedian approach to postdural puncture headache remains controversial. The objective of this prospective randomized study was to compare Sprotte, Quincke and Atraucan needles as well as the midline and the paramedian approach in terms of postdural puncture headache and spinal anesthesia failure in patients undergoing Caesarean section. METHODS: 655 patients were randomized to 5 groups. A midline approach was used in four groups. The spinal needles were the 25G Sprotte, 27G Sprotte, 26G Atraucan and 25G Quincke. In the fifth group a 25G Quincke needle was used by the paramedian approach. RESULTS: The incidence of postdural puncture headache was 0% in both 25G and 27G Sprotte groups, 2.5% in the 26G Atraucan group, and 7.2% and 2.7% in the 25G Quincke midline and paramedian approach respectively. A significant difference in terms of postdural puncture headache was found between 25G Sprotte and 25G Quincke needles (P = 0.004), while the failure rate was similar between these two needles. A significant difference in spinal anesthesia failure rate was observed between midline and paramedian approaches (P = 0.041). CONCLUSIONS: Sprotte but not Atraucan needle design correlates with lower incidence of postdural puncture headache compared to Quincke design. Sprotte needles are not associated with a higher spinal anesthesia failure compared to Quincke needles. The incidence of postdural puncture headache by the paramedian approach is not significantly reduced whereas the spinal anesthesia failure rate is increased in comparison to the midline approach.

Central neurological complications following obstetric neuraxial blockade.

PURPOSE OF REVIEW: Central neuraxial blockade is increasingly the anaesthetic management of choice for parturients, including in higher risk pregnancies. Although they are usually effective and safe, there are potentially devastating neurological complications that may present either overtly or insidiously. A thorough understanding of the variety of potential neurological complications is essential to adequately consent patients in addition to diagnosing and managing complications following neuraxial anaesthesia. This review aims to describe a number of potential neurological injuries that may occur and suggested management based on available evidence. RECENT FINDINGS: Current evidence supports neuraxial anaesthesia as a safe management strategy in low and many higher risk pregnancies, with a low overall incidence of neurological complications. Neuraxial blockade is safe in patients with platelet counts greater than 70 000/µl and the risk of infective complications secondary to epidural catheterization remains low until day five post procedure. There is also some early evidence supporting the use of transnasal local anaesthetic as a strategy for managing postdural puncture headache. SUMMARY: Difficulty remains in establishing absolute risk of complications and optimal management strategies given the low overall number of patients affected and heterogeneity of therapy. There may be a role for centralized registration of postneuraxial complications in obstetric patients to further develop our collective understanding of these conditions.

Low-dose spinal anesthesia for cesarean section to prevent spinal-induced hypotension.

PURPOSE OF REVIEW: Low-dose combined spinal epidural (CSE) anesthesia is a common technique to anesthetize women for cesarean section. It is used to reduce the incidence of hypotension while providing excellent anesthetic conditions. RECENT FINDINGS: Low spinal doses produce effective anesthesia but of limited duration. Therefore, an epidural catheter (and thus CSE) is required to guarantee pain-free surgery. Recent work confirmed that lower spinal doses can reduce significantly hypotension. SUMMARY: Low-dose CSE is a valuable strategy to anesthetize pregnant women for cesarean section but requires attention and training.

The Effectiveness of Applying Soft Tissue Bonding Adhesive Composed of 2-Ethyl Cyanoacrylate to Epidural Catheter Fixations Using Film Dressings: An Open-Label, Randomized, Parallel-Group Comparative Study.

BACKGROUND: Insufficient fixation of an epidural catheter may result in migration of the catheter and eventual catheter failure. However, the best fixation method remains to be established. Aron Alpha A (2-ethyl cyanoacrylate) adhesive is approved for clinical use and can be used for surgical adhesion to both skin and blood vessels. We hypothesized that the addition of Aron Alpha A adhesive to film dressing would result in consistent and dependable catheter fixation. METHODS: In this study, 58 women who were scheduled for cesarean delivery under spinal and epidural anesthesia were recruited. Patients were randomly assigned to a control or treatment group. In the control group, the catheter was fixed solely by film dressing. In the treatment group, a small amount of Aron Alpha A was applied at 2 sites along the catheter. The fixation area was then covered by film dressing. The catheter insertion length was recorded after fixation (T0), immediately postoperatively (T1), on postoperative day 1 (T2), and when the catheter was removed (T3). The change in insertion length from T0 to T3 between the 2 groups was the primary outcome measure. The incidence of catheter failure was also recorded. For all comparisons, P < .05 was considered statistically significant. RESULTS: Initially, 58 women were enrolled; however, 3 patients were excluded. From the remaining 55 patients, 27 and 28 were assigned to the control and treatment groups, respectively, and were evaluated. The change in insertion length from T0 to T3 was significantly more in the control group compared with the treatment group (-1.9 ± 2.2 vs 0 ± 0 cm, respectively; P < .001). In the control group, 11 catheters (41%) failed; in the treatment group, all catheters provided effective analgesia throughout the study (P < .001). CONCLUSIONS: Epidural catheter fixation using film dressing combined with 2-ethyl cyanoacrylate adhesive application at 2 sites along the catheter resulted in secure fixation in patients receiving postoperative epidural analgesia for cesarean delivery.

Insertion of an intrathecal catheter following a recognised accidental dural puncture reduces the need for an epidural blood patch in parturients: an Australian retrospective study.

BACKGROUND: There is no clear consensus about how best to prevent post-dural puncture headache (PDPH) following an accidental dural puncture in parturients. Our primary objective was to investigate whether the insertion of an intrathecal catheter following accidental dural puncture reduces the incidence of PDPH and therapeutic epidural blood patch. METHODS: Anaesthetic records from January 2009 to December 2015 were reviewed retrospectively and parturients who had an accidental dural puncture and/or PDPH were identified. Data from those with a recognised dural puncture in whom an intrathecal catheter was inserted at the time of accidental dural puncture (ITC group) were compared to those without an intrathecal catheter (non-ITC group), as were outcomes of patients with an intrathecal catheter for ≥24 hours compared to <24 hours. RESULTS: Of 94 recognised accidental dural punctures, 66 were in the ITC group (37 for ≥24 h) and 28 in the non-ITC group. In the ITC group, 22 (33.3%) required an epidural blood patch in comparison to 19 (67.9%) in the non-ITC group (P <0.01, 95% CI 12.5 to 52.0). In the ITC group, 62 (93.9%) developed PDPH in comparison to 28 (100%) in the non-ITC group (P=0.186, 95% CI -6.55 to 14.57). Intrathecal catheter insertion for ≥24 h obviated the need for an epidural blood patch in 28 (75.7%) parturients, compared to 13 (59.1%) if <24 h (P=0.184, 95% CI -7.08 to 39.72). CONCLUSION: Inserting an intrathecal catheter after a recognised accidental dural puncture significantly reduced the need for an epidural blood patch.

Medical Simulation as a Vital Adjunct to Identifying Clinical Life-Threatening Gaps in Austere Environments.

BACKGROUND: Maternal mortality and morbidity are major causes of death in low-resource countries, especially those in Sub-Saharan Africa. Healthcare workforce scarcities present in these locations result in poor perioperative care access and quality. These scarcities also limit the capacity for progressive development and enhancement of workforce training, and skills through continuing medical education. Newly available low-cost, in-situ simulation systems make it possible for a small cadre of trainers to use simulation to identify areas needing improvement and to rehearse best practice approaches, relevant to the context of target environments. METHODS: Nurse anesthetists were recruited throughout Sierra Leone to participate in simulation-based obstetric anesthesia scenarios at the country's national referral maternity hospital. All subjects participated in a detailed computer assisted training program to familiarize themselves with the Universal Anesthesia Machine (UAM). An expert panel rated the morbidity/mortality risk of pre-identified critical incidents within the scenario via the Delphi process. Participant responses to critical incidents were observed during these scenarios. Participants had an obstetric anesthesia pretest and post-test as well as debrief sessions focused on reviewing the significance of critical incident responses observed during the scenario. RESULTS: 21 nurse anesthetists, (20% of anesthesia providers nationally) participated. Median age was 41 years and median experience practicing anesthesia was 3.5 years. Most participants (57.1%) were female, two-thirds (66.7%) performed obstetrics anesthesia daily but 57.1% had no experience using the UAM. During the simulation, participants were observed and assessed on critical incident responses for case preparation with a median score of 7 out of 13 points, anesthesia management with a median score of 10 out of 20 points and rapid sequence intubation with a median score of 3 out of 10 points. CONCLUSION: This study identified substantial risks to patient care and provides evidence to support the feasibility and value of in-situ simulation-based performance assessment for identifying critical gaps in safe anesthesia care in the low-resource settings. Further investigations may validate the impact and sustainability of simulation based training on skills transfer and retention among anesthesia providers low resource environments.

Investigating a Needle-Based Epidural Procedure in Obstetric Anesthesia.

This study investigates the safety and efficacy of a large-dose, needle-based epidural technique in obstetric anesthesia. The technique differs from a standard, catheter-based approach in that the anesthetic dose is administered through an epidural needle prior to insertion of the epidural catheter. Using a data-driven informatics and machine learning approach, our findings show that the needle-based technique is faster and more dose-effective in achieving sensory level. We also find that injecting large doses in the epidural space through the epidural needle is safe, with complication rates similar to those reported in published literature for catheter-based technique. Further, machine learning reveals that if the needle dose is kept under 18 ml, the resulting hypotension rate will be significantly lower than published results. The machine learning framework can predict the incidence of hypotension with 85% accuracy. The findings from this investigation facilitate delivery improvement and establish an improved clinical practice guideline for training and for dissemination of safe practice.

Comparison of Epidrum, Epi-Jet, and Loss of Resistance syringe techniques for identifying the epidural space in obstetric patients.

BACKGROUND: Identifying the epidural space is essential during epidural anesthesia (EA). Pressure of the epidural space in pregnancy is higher than that in nonpregnant woman. Loss of resistance (LOR) method is the most commonly preferred method for identifying the epidural space. Epidrum and Epi-Jet are recently innovated supporting devices that facilitate identifying process for epidural space. In this study we aimed to compare Epidrum, Epi-Jet, and LOR methods in identifying the epidural space, feasibility of technique. METHODS: Two hundred and forty pregnant women who were scheduled for caesarian section surgery under lumbar EA or combined spinal epidural anesthesia (CSEA) were randomized into three groups (Group I Epidrum, n = 80), Group II (Epi-Jet, n = 80), and Group III (LOR, n = 80). We recorded the time required to identify the epidural space and deflation of Epidrum balloon and Epi-Jet syringe, number of attempts, additional methods used to identify epidural space, usefulness of methods, accuracy of identification of epidural space, and outcomes of epidural catheterization. RESULTS: There were no significant differences between the groups with respect to demographic data, duration of deflation of Epidrum balloon and Epi-Jet syringe and distance between skin and epidural space. The mean time required to enter epidural space in Group I was shorter than that in Group II (P = 0.031). Feasibility of Epi-Jet was easier than that of Epidrum (P = 0.015). Number of uncertainties of epidural space identification was higher in Group I than that in Group II (P = 0.009). Also, the requirement for LOR to confirm epidural space and failure rates was higher in Group I than Group II (P < 0.001). CONCLUSION: We suggest that Epi-Jet is superior to Epidrum in pregnant patients in terms of clarity of epidural space identification, usefulness, and success rates of EA or CSEA.

The use of ultrasound in obstetric anesthesia.

PURPOSE OF REVIEW: The current review considers an array of recent applications for point-of-care ultrasound in clinical practice including diagnostic and therapeutic procedures that may be relevant for the obstetric anesthesiologist. The rapid advancement of technology and clinical applications for bedside ultrasound in obstetric anesthesiology requires an appraisal of the limitations and uses. RECENT FINDINGS: The review presents the most recent literature describing ultrasound-guided airway assessments, airway management, cricothyroidotomy, transthoracic echocardiography, gastric volume assessments, point-of-care lung ultrasound diagnoses, intracranial pressure assessments, vascular access, neuraxial blocks, and transversus abdominis plane blocks. Each ultrasound technique is presented along with the most recent advances in knowledge and some limitations to integration of these ultrasound skills in clinical practice. SUMMARY: Anesthesiologists have clearly embraced this facile versatile tool for bedside diagnostics and procedures. One limitation to widespread adoption is availability of suitable ultrasound skills and technology. Many of these ultrasound techniques have not yet established clear patient benefit, yet the sheer breadth of ultrasound techniques reported in the past few years demonstrate that our colleagues are becoming more proficient. It is important to follow the development of this emerging field to be aware of limitations to learning these skills and their potential clinical benefit. Proficiency in some of these point-of-care ultrasound techniques may become prerequisite for obstetric anesthesiologists to provide the best care.

Increasing body mass index predicts increasing difficulty, failure rate, and time to discovery of failure of epidural anesthesia in laboring patients.

STUDY OBJECTIVE: Obese parturients both greatly benefit from neuraxial techniques, and may represent a technical challenge to obstetric anesthesiologists. Several studies address the topic of obesity and neuraxial analgesia in general, but few offer well described definitions or rates of "difficulty" and "failure" of labor epidural analgesia. Providing those definitions, we hypothesized that increasing body mass index (BMI) is associated with negative outcomes in both categories and increased time needed for epidural placement. DESIGN: Single center retrospective chart review. SETTING: Labor and Delivery Unit of an inner city academic teaching hospital. PATIENTS: 2485 parturients, ASA status 2 to 4, receiving labor epidural analgesia for anticipated vaginal delivery. INTERVENTIONS: None. MEASUREMENTS: We reviewed quality assurance and anesthesia records over a 12-month period. "Failure" was defined as either inadequate analgesia or a positive test dose, requiring replacement, and/or when the anesthesia record stated they failed. "Difficulty" was defined as six or more needle redirections or a note indicating difficulty in the anesthesia record. MAIN RESULTS: Overall epidural failure and difficulty rates were 4.3% and 3.0%, respectively. Patients with a BMI of 30kg/m2 or higher had a higher chance of both failure and difficulty with two and almost three fold increases, respectively. Regression analysis indicated that failure was best predicted by BMI and less provider training while difficulty was best predicted by BMI. Additionally, increased BMI was associated with increased time of discovery of epidural catheter failure. CONCLUSIONS: Obesity is associated with increasing technical difficulty and failure of neuraxial analgesia for labor. Practitioners should consider allotting extra time for obese parturients in order to manage potential problems.

[In situ broken 27-gauge spinal needle in a repeated caesarean delivery : Case report and literature review]. / In situ abgebrochene 27-Gauge-Spinalnadel bei einer Re-Resectio : Fallbericht und Übersicht über die Literatur.

We report the rare case of an in situ fracture of a spinal needle within the setting of repeated caesarean delivery in a 28-year-old pregnant woman and discuss the responsible underlying factors. In particular, a wrong technique, limited experience, difficulties to identify the anatomical landmarks, as well as the use of spinal needles smaller than 25 G might promote such a complication. In order to ensure the stability of the spinal needle and to avoid an in situ fracture, the spinal needle should be never moved without the stylet. In case of repeated bone contact, a well-experienced anaesthetist should be consulted, the spinal needle should be replaced and the use of ultrasound is recommended. Next, the use of an atraumatic spinal needle greater than 27 G should be considered to facilitate intrathecal puncture and to avoid the in situ fracture of a spinal needle. Within this context, the risk of post-spinal puncture headache should be balanced. If an in situ fracture of a spinal needle happens, its subsequent removal should be planned without delay by an interdisciplinary team and the anaesthetic method should be chosen with consideration of patient-specific risk factors.