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.

Comparison of Programmed Intermittent Epidural Boluses With Continuous Epidural Infusion for the Maintenance of Labor Analgesia: A Randomized, Controlled, Double-Blind Study.

BACKGROUND: Programmed intermittent epidural boluses may improve the spread of local anesthetics compared to continuous epidural infusion, improving labor analgesia and obstetric outcomes. However, there are limited data from studies using commercially available pumps capable of coadministering programmed intermittent epidural boluses or continuous epidural infusion with patient-controlled epidural analgesia. Therefore, we performed this prospective, randomized, double-blind study to compare the impact of programmed intermittent epidural boluses versus continuous epidural infusion on labor analgesia and maternal/neonatal outcomes. We hypothesized that programmed intermittent epidural boluses will result in lower patient-controlled epidural analgesia consumption compared to that with continuous epidural infusion. METHODS: Following standardized initiation of epidural labor analgesia, women were randomized to receive 0.1% ropivacaine with 2 µg/mL fentanyl as 6-mL programmed intermittent epidural boluses every 45 minutes or continuous epidural infusion at 8 mL/h in a double-blind fashion with similar patient-controlled epidural analgesia settings in both groups. The primary outcome was patient-controlled epidural analgesia consumption per hour. Secondary outcomes included a need for physician interventions, patterns of patient-controlled epidural analgesia use, motor blockade, number of patients who developed hypotension, pain scores, duration of second stage of labor, mode of delivery, and maternal satisfaction. RESULTS: We included 120 patients (61 in programmed intermittent epidural boluses group and 59 in continuous epidural infusion group) in the analysis. The median (interquartile range) patient-controlled epidural analgesia volume consumed per hour was not significantly different between the groups: 4.5 mL/h (3.0-8.6 mL/h) for the continuous epidural infusion group and 4.0 mL/h (2.2-7.1 mL/h) for the programmed intermittent epidural boluses group (P = .17). The Hodges-Lehmann location shift estimate of the difference (95% CI) from the continuous epidural infusion to the programmed intermittent epidural boluses group is 0.9 mL/h (-0.4 to 2.2 mL/h). There were also no significant differences between the groups in any of the secondary outcomes except for higher median (interquartile range) patient-controlled epidural analgesia attempts per given ratio per hour in the programmed intermittent epidural bolus group (0.17 [0.10-0.30] vs 0.12 [0.08-0.18]; P = .03) and more motor block in the continuous epidural infusion group (those with Bromage score <5, 27.5% vs 50.0%; P = .03). CONCLUSIONS: Under the conditions of our study, we did not find improved outcomes with programmed intermittent epidural boluses compared to continuous epidural infusion except for less motor block with programmed intermittent epidural boluses. Future studies should assess whether smaller but clinically important differences exist and evaluate different parameters of programmed intermittent epidural boluses to optimize analgesia and outcomes with this mode of analgesia.

Ultrasound-guided transmuscular quadratus lumborum catheters for elective caesarean section: A protocol for a single-centre, double-blind randomised trial.

BACKGROUND: Management of moderate-to-severe post-operative pain after elective caesarean section (ECS) is internationally primarily based on either epidural catheters or opioids. However, both techniques are associated with some undesirable adverse events. Bilateral transmuscular quadratus lumborum (TQL) block has proven to reduce opioid consumption significantly in the first 24 post-operative hours following ECS and prolong time to first opioid (TFO) (Hansen CKD, Steingrimsdottir M, Laier GE, et al. Reg Anesth Pain Med. 2019; 10.1136/rapm-2019-100540). We present a randomised controlled trial aiming to investigate whether continuous analgesia via bilateral TQL catheters can prolong TFO after ECS. METHODS: This study is a double-blind, randomised, placebo-controlled trial. Patients should be 18 years or older and scheduled for ECS under spinal anaesthesia to be included. Main exclusion criteria are inability to cooperate, excessive daily intake of opioids and difficult ultrasound visualisation of muscular and fascial structures. Participants are randomised to receive ultrasound-guided injection of either 30 mL ropivacaine 0.2% bilaterally and an elastomeric pump containing 0.2% ropivacaine, or 30 mL saline bilaterally and an elastomeric pump containing saline, 2 hours after catheter placement. The primary endpoint is TFO. Secondary outcomes include pain intensity on a numeric rating scale (NRS), accumulated morphine consumption during 24 hours, displacement frequency of catheters and morphine-related adverse events. RECRUITMENT PERIOD: Four patients were included from September 2018 to November 2018. Inclusion was resumed in June 2019 and will continue until 24 patients with useful data have been included in the trial. Expected inclusion period is 10-14 months. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03663478. EudraCT: 2017-003625-15.

Use of a novel non-invasive respiratory monitor to study changes in pulmonary ventilation during labor epidural analgesia.

Measuring continuous changes in maternal ventilation during labor neuraxial analgesia is technically difficult. Consequently, the magnitude of pulmonary minute ventilation (MV) alterations following labor analgesia remains unknown. We hypothesized that a novel, bio-impedance based non-invasive respiratory monitor would provide this information. Furthermore, we sought to determine if an association between changes in MV and maternal temperature existed. Following calibration with a Haloscale Standard Wright Respirometer, the ExSpiron respiratory volume monitor (RVM) measured MV, respiratory rate (RR), and tidal volume (TV) in 41 term parturients receiving epidural analgesia. Simultaneously, maternal oral temperatures were recorded at pre-specified hourly intervals after epidural analgesia initiation until delivery. Cumulative MV changes were calculated as the integral of MV change over time: MV [Formula: see text], where T represents the time between epidural placement and variable measurement. The association between changes in MV and cumulative MV versus maternal temperature was determined by comparing patients whose temperature did or did not increase by ≥ 0.5 °C. After initiation of epidural analgesia, MV decreased by 11.1 ± 27.6% [mean ± SD] at 30 min, p = 0.006, and 19.8 ± 26.1% at 2 h compared to baseline (12.6 ± 7.3 L/min at baseline vs. 15.3 ± 6.3 L/min at 2 h, p < 0.001), Minute ventilation remained decreased at 4 h by 14.3 ± 31.4% (p = 0.013). The cumulative MV also decreased by 437 ± 852 L [mean ± SD], p = 0.009) at 2 h and by 795 ± 1431 L, p < 0.001) at 4 h following epidural analgesia initiation, compared to baseline. The association between changes in cumulative MV and maternal temperature following epidural placement was weak (R < 0.3); however, a decrease in MV at 30 min (p = 0.002) and cumulative MV at 2 h (p = 0.012) was observed in women whose temperature increased by at least 0.5 °C during labor. Our findings suggest that RVM can be a useful noninvasive technology to investigate pulmonary physiology during labor. The association between maternal MV and temperature change during labor analgesia deserves further investigation.Trial Registrationwww.clinicaltrials.gov (NCT02339389).

Do Epidural Catheter Size and Flow Rate Affect Bolus Injection Pressure in Different Programmed Intermittent Epidural Bolus Regimens? An In Vitro Study.

BACKGROUND: The optimal programmed intermittent epidural bolus regimen for labor analgesia remains unknown. Some studies indicate that better drug spread in the epidural space results from greater injection pressure; however, there is a lack of data regarding the maximum pressure generated by epidural bolus injection using different catheters and flow rates. METHODS: We evaluated the flow and pressure characteristics of 11 commonly used epidural catheters combined with 3 different infusion pumps that deliver epidural infusions according to the programmed intermittent epidural bolus regimen. Pressure changes were measured over time at flow rates of 100, 250, and 400 mL·hour and with a bolus volume of 10 mL. To account for repeated measures, linear mixed models were used. Features were selected with a backward stepwise procedure continued until only statistically significant variables were left in the model. RESULTS: We performed 660 measurements. The mean maximal pressure generated during bolus injection ranged from 86 to 863 mm Hg for different flow rates and catheter designs. The interaction between flow rate and catheter gauge resulted in 1.31, 1.65, and 2.00 mm Hg of pressure increase for 18G, 19G, and 20G catheters, respectively, per 1 mL·hour of increased flow rate (P< .001). Analyses including wire-reinforced catheters revealed a 1.16, 1.76, and 2.36 mm Hg pressure increase for 18G, 19G, and 20G catheters, respectively, per 1 mL·hour of increased flow rate (P< .001). In some cases, it triggered the occlusion pump alarm. CONCLUSIONS: Significant differences were observed in the in vitro maximum pressure value among the various catheter and flow rate combinations with a higher pressure value for wire-reinforced catheters used in the study. The optimal flow rate and epidural catheter combination may allow for delivery of the bolus with high flow rate without triggering the occlusion alarm.

Reducing breakthrough pain during labour epidural analgesia: an update.

PURPOSE OF REVIEW: Neuraxial techniques are the current gold standard for labour analgesia, but are associated with up to 25% incidence of breakthrough pain. In this review, we aim to update clinicians on the latest research pertaining to the optimization of neuraxial labour analgesia. RECENT FINDINGS: Attempts to improve the efficacy and reliability of epidural analgesia while minimizing adverse effects have resulted in the rising popularity of combined spinal epidural and the dural puncture epidural (DPE). Recent studies have focused on determining the safety, efficacy, and optimization of the DPE technique.Another research focus is on the development of individualized therapy in which patients may titrate their own labour analgesia according to their varying requirements, possibly augmented with computer-aided feedback systems and automated mandatory bolus techniques that automatically adjust drug delivery to the patients' analgesic requirements. The addition of a risk-stratification model based on maternal, anaesthetic, and obstetric factors will facilitate early institution of individualized therapy to forestall breakthrough pain in higher risk patients. SUMMARY: Recent advances in combined spinal epidural, DPE, automated mandatory bolus, and individualized therapies have advanced our goal of providing effective labour analgesia that is titrated to changing analgesic requirements during labour and delivery and reducing breakthrough pain.

Epidural test dose in obstetric patients: should we still use it?

PURPOSE OF REVIEW: As the application of a test dose after epidural catheter insertion in obstetrics has recurrently been associated with serious adverse events affecting both maternal and foetal outcomes, the question whether to test or not remains a controversial issue. RECENT FINDINGS: Present guidelines do not provide clear recommendations in this regard and several recent surveys indicate a heterogeneity in clinical routine. SUMMARY: Physiological alterations during pregnancy and labour restrict the use and also the validity of traditional test agents. Epinephrine is not appropriate to detect a vascular insertion in labour and the application of a local anaesthetic test dose may lead to dose-dependent fatal consequences should the catheter be intrathecal, due to an increased sensitivity in parturients. Given the current practice of opioid-amended-low-concentration epidurals, the waiving of a test dose results at worst in a failed epidural, a stark contrast to the potentially severe to fatal complications of a 'traditional' test dose. Hence, an originally preventive measure providing potentially more harm than the consequences of the situation aimed to prevent, should not be recommended. A simple fractionated administration of the initial analgesic dose seems reasonable though.

Development and validation of a predictive risk factor model for epidural re-siting in women undergoing labour epidural analgesia: a retrospective cohort study.

BACKGROUND: Epidural catheter re-siting in parturients receiving labour epidural analgesia is distressing to the parturient and places them at increased complications from a repeat procedure. The aim of this study was to develop and validate a clinical risk factor model to predict the incidence of epidural catheter re-siting in labour analgesia. METHODS: The data from parturients that received labour epidural analgesia in our centre during 2014-2015 was used to develop a predictive model for epidural catheter re-siting during labour analgesia. Multivariate logistic regression analysis was used to identify factors that were predictive of epidural catheter re-siting. The forward, backward and stepwise variable selection methods were applied to build a predictive model, which was internally validated. The final multivariate model was externally validated with the data collected from 10,170 parturients during 2012-2013 in our centre. RESULTS: Ninety-three (0.88%) parturients in 2014-2015 required re-siting of their epidural catheter. The training data set included 7439 paturients in 2014-2015. A higher incidence of breakthrough pain (OR = 4.42), increasing age (OR = 1.07), an increased pain score post-epidural catheter insertion (OR = 1.35) and problems such as inability to obtain cerebrospinal fluid in combined spinal epidural technique (OR = 2.06) and venous puncture (OR = 1.70) were found to be significantly predictive of epidural catheter re-siting, while spontaneous onset of labour (OR = 0.31) was found to be protective. The predictive model was validated internally on a further 3189 paturients from the data of 2014-2015 and externally on 10,170 paturients from the data of 2012-2013. Predictive accuracy of the model based on C-statistic were 0.89 (0.86, 0.93) and 0.92 (0.88, 0.97) for training and internal validation data respectively. Similarly, predictive accuracy in terms of C-statistic was 0.89 (0.86, 0.92) based on 2012-2013 data. CONCLUSION: Our predictive model of epidural re-siting in parturients receiving labour epidural analgesia could provide timely identification of high-risk paturients required epidural re-siting.

Does Preprocedural Ultrasound Increase the First-Pass Success Rate of Epidural Catheterization Before Cesarean Delivery? A Randomized Controlled Trial.

BACKGROUND: Preprocedural ultrasound may improve the efficacy and safety of epidural catheterization, especially in difficult cases. Most studies of ultrasound-assisted epidural catheterization in the obstetric population are dated and nonblinded with inconsistent designs. This double-blind, randomized controlled study aimed to compare the ultrasound-assisted with the conventional palpation techniques for epidural catheterization in parturients undergoing cesarean delivery. We hypothesized that the use of preprocedural ultrasound would increase the success rate of epidural catheterization at the first needle pass. METHODS: Eligible subjects were American Society of Anesthesiologists physical status II parturients with full-term singleton pregnancy undergoing elective cesarean delivery using double-interspace combined spinal-epidural anesthesia. Exclusion criteria were age <19 or >40 years, body mass index ≥35 kg/m, women presenting in labor or having any contraindication to neuraxial anesthesia, marked spinal deformity, previous spinal surgery, or impalpable anatomical landmarks. One hundred ten patients were randomly allocated into 2 equal groups (palpation and ultrasound groups). All procedures were performed by a single experienced anesthesiologist. Patients and investigators assessing the outcome data were blinded to group allocation. A systematic spinal ultrasound assessment and a sham procedure were performed in the ultrasound and palpation groups, respectively, before attempting epidural catheterization. The primary outcome was the rate of successful epidural catheterization at the first needle pass. Secondary outcomes were the rate of successful epidural catheterization at the first skin puncture, number of performed needle passes and skin punctures, duration of the epidural procedure, patient satisfaction from the procedure, and complications of the procedure (incidence of unintentional dural and vascular punctures, failed block, unilateral or patchy block, and backache). RESULTS: Data from 108 patients (55 patients in the palpation group and 53 patients in the ultrasound group) were analyzed. The rate of successful epidural catheterization at the first needle pass was 60% in the palpation group and 58.5% in the ultrasound group (95% confidence interval of the difference in proportions between groups is -18.5% to 21.6%; P > 0.99). There were no significant differences between the 2 groups in the success rate at the first skin puncture, the number of needle passes and skin punctures, or patient satisfaction. The median (range) duration of the epidural procedure was 185 (57-680) seconds in the ultrasound group and 215 (114-720) seconds in the palpation group (P = 0.036 with the Mann-Whitney U test and P = 0.083 with the Student t test with unequal variances). The overall rate of complications of the procedure was low in both groups. CONCLUSIONS: For experienced anesthesiologists, it remains unclear whether preprocedural ultrasound improves the epidural catheterization technique in parturients with palpable anatomical landmarks undergoing cesarean delivery.

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.

Combined Spinal Epidural Technique for Labor Analgesia Does Not Delay Recognition of Epidural Catheter Failures: A Single-center Retrospective Cohort Survival Analysis.

BACKGROUND: It is unclear whether recognition of epidural catheter failures is delayed with combined spinal epidural technique (CSE) compared to traditional epidural technique (EPID) when used for labor analgesia. The authors hypothesized that recognition of failed catheters is not delayed by CSE. METHODS: Anesthetic, obstetric, and quality assurance records from 2,395 labor neuraxial procedures (1,440 CSE and 955 EPID) performed at Forsyth Medical Center (Winston-Salem, North Carolina) between June 30 and December 31, 2012, were retrospectively analyzed. The primary outcome was catheter survival (failure-free) time during labor analgesia. A proportional hazards model with the counting method was used to assess relationships between the techniques and survival (failure-free) time of catheters, while controlling for subjects' body mass index and providers' level of training in the final best-fit multivariable regression model. RESULTS: Cumulative incidence of epidural catheter failures was 6.6% for CSE and 11.6% for EPID (P = 0.001). In the multivariable regression model, catheters placed with CSE versus epidural were less likely to fail (hazard ratio, 0.58; 95% CI, 0.43 to 0.79; P = 0.0002) for labor analgesia. Among the catheters that failed, there was no overall difference in failure time course between the techniques (hazard ratio, 1.17; 95% CI, 0.89 to 1.54; P = 0.26) even though more failed catheters with CSE (48.4%) than with EPID (30.6%) were recognized within the first 30 min of placement (P = 0.009). CONCLUSIONS: In this cohort, CSE has a significantly lower risk of overall epidural catheter failures than EPID and does not delay recognition of epidural catheter failures. Choice of CSE versus EPID should be based on overall risk of failure, efficacy, and side effects.

Intrapartum epidural fixation methods: a randomised controlled trial of three different epidural catheter securement devices.

This randomised controlled trial investigated the efficacy of Epi-Fix(™) , LockIt Plus(®) and Tegaderm(™) as fixation devices for intrapartum epidural catheters. One hundred and sixty-five women requesting intrapartum epidural analgesia were randomised to receive different fixation devices to secure their epidural catheter. The amount of epidural catheter migration (measured to the nearest 0.5 cm) was analysed for three devices: Epi-Fix (n = 55); LockIt Plus (n = 54); and Tegaderm dressing (n = 51). Median (IQR [range]) catheter migration for Epi-Fix was 1.0 cm (0.0-2.0 [-2.0 to 9.5]), vs 0.0 cm (0.0-0.5 [-1.0 to 5.5]) for LockIt Plus and 0.5 cm (0.0-1.8 [-1.5 to 8.0]) for Tegaderm (p = 0.003). Thirty-eight (69.1%) epidural catheters secured with Epi-Fix migrated < 2.0 cm, compared with 49 (90.7%) with LockIt Plus and 40 (78.4%) with Tegaderm. Sixteen epidural catheters required resiting due to failure of analgesia of which 12 (75.0%) occurred in patients with epidural catheters that had migrated ≥ 2.0 cm. This study shows that intrapartum epidural catheters secured with the LockIt Plus device exhibit less catheter migration compared with fixation with Epi-Fix and Tegaderm.

Continuous Spinal Analgesia for Labor and Delivery: An Observational Study with a 23-Gauge Spinal Catheter.

BACKGROUND: The aim of the study was to assess postdural puncture headache, pain relief, motor blockade, and success rate of conversion to cesarean delivery anesthesia of a 23-gauge spinal catheter (Wiley Spinal®) for labor analgesia. METHODS: After insertion of the spinal catheter, intrathecal bupivacaine 2.5 mg was administered, followed by patient-controlled intrathecal analgesia (basal infusion of 0.0625% bupivacaine with fentanyl 2 µg/mL at a rate of 2 mL/h, demand bolus 1 mL, lockout interval 20 minutes). Bupivacaine 0.5%, up to 25 mg, was administered via the catheter along with fentanyl 20 µg for cesarean delivery anesthesia, if necessary. The catheter was removed after delivery or after 12 hours, whichever was longer. RESULTS: One hundred thirteen women were enrolled. In 12 women (11%), the catheter was not successfully inserted or maintained in position. Continuous spinal analgesia was used in 101 women. Three women (2.6%, 95% confidence interval, 0.7%-8.1%) developed postdural puncture headache. There were 83 spontaneous, 12 operative vaginal, and 18 cesarean deliveries. Of the 18 cesarean deliveries, 16 had continuous spinal analgesia when the decision was made to perform a cesarean delivery; conversion from labor analgesia to cesarean anesthesia was successful in 15 women (94%, 95% confidence interval, 67.7%-99.7%). CONCLUSIONS: The 23-gauge spinal catheter can be used for analgesia for labor. It can also be converted to surgical anesthesia for cesarean deliveries. Further studies are warranted to determine whether the spinal catheter will be a useful addition to the neuraxial techniques available for obstetric anesthesia care.

The Relationship of Body Mass Index with the Incidence of Postdural Puncture Headache in Parturients.

BACKGROUND: Unintentional dural puncture is a known risk after epidural or combined spinal-epidural procedures, occurring in approximately 1% of labor epidural catheters placed in parturients with normal body habitus but may be as high as 4% in morbidly obese parturients. Anecdotal experience and limited publications suggest that an inverse relationship between body mass index (BMI) and postdural puncture headache (PDPH) may exist. We hypothesized that parturients with increased BMI have a lower incidence of PDPH than those with a lower BMI after unintentional dural puncture. METHODS: After IRB approval, we performed a retrospective cohort study by medical record review. Case logs from our institution were searched for patients with documented unintentional dural puncture during attempted neuraxial analgesia between January 1, 2004, and December 13, 2013. The primary outcome was the incidence of PDPH. The association between BMI and PDPH was assessed using binary logistic regression, and the Wilcoxon-Mann-Whitney odds and confidence intervals (CIs) for a random pair of BMI values from a PDPH subject compared with a non-PDPH subject were calculated from the area under the receiver operator characteristics curve. Classification tree analysis was used to determine the BMI cutoff value for the risk of developing a PDPH. The presence or absence of second-stage labor pushing and placement of an intrathecal catheter after unintentional dural puncture were compared in parturients with and without PDPH using the Fisher exact test. BMI groups were dichotomized at the cutoff value (low and high BMI groups). We compared the incidence of a PDPH between high and low BMI groups using the Fisher exact test after controlling for pushing during labor and placement of an intrathecal catheter at the time of unintentional dural puncture. Secondary analysis evaluated the highest reported numeric rating of pain scores for headache and the need for an epidural blood patch between BMI groups. RESULTS: Unintentional dural puncture was identified in 518 (0.53%) patients (95% CI, 0.48%-0.58%). The overall incidence of PDPH after unintentional dural puncture was 51% (95% CI, 46%-55%). The Wilcoxon-Mann-Whitney odds for a random pair of BMI values from a PDPH subject compared with a non-PDPH subject was 0.74 (95% CI, 0.60-0.90, P = 0.001). The odds ratio for developing a PDPH in women who pushed during delivery was 2.4 (95% CI, 1.2-3.9, P = 0.001) compared with women who did not push. Classification tree analysis identified a BMI cutoff value of 31.5 kg/m for prediction of a PDPH. The incidence of PDPH in parturients with a BMI ≥31.5 kg/m (39%) was lower than in parturients with a BMI <31.5 kg/m (56%; difference -17%; 95% CI, -7% to -26%, P = 0.0004). The odds ratio for a PDPH in the high BMI compared with the low BMI group was 0.36 (95% CI, 0.14-0.92, P = 0.04) in parturients who pushed during labor and 0.62 (95% CI, 0.41-0.97, P = 0. 04) in parturients who did not push. After the unintentional dural puncture, 112 (22%) parturients had an intrathecal catheter placed. The incidence of PDPH in parturients with an intrathecal catheter was 59% (95% CI, 49%-68%) compared with 48% (95% CI, 43%-54%) in women with an epidural catheter (P = 0.06). Median (interquartile range) headache severity (0-10 verbal rating scale) was 8 (6-9) and did not differ between parturients in the high versus low BMI groups (P = 0.61). The rate of epidural blood patch administration for PDPH treatment was similar in BMI groups (difference -12%; 95% CI, 4 to -27, P = 0.13). CONCLUSIONS: The findings are consistent with previous reports of decreased PDPH incidence after unintentional dural puncture in parturients with an increased BMI, even after controlling for pushing during labor. Severity of headache and need for epidural blood patch treatment were similar in low and high BMI groups.

The unexpected epidural: a case report.

BACKGROUND: We report the peculiar case of a patient with a retained large epidural catheter fragment, incidentally found 12 years after its placement. Our primary aim is to emphasize how the breakage and retention of even exceptionally large portions of this device can go undetected. The patient can be completely asymptomatic and, with no clue that such a foreign body exists, the presentation of its potential complications can be subtle and misleading. To our knowledge, this is the first reported case of the incidental discovery of such a large fragment so many years after its placement. No consensus exists about how to handle this complication, therefore our report adds to the amount of available evidence. CASE PRESENTATION: A 53-year-old caucasian female with a history of diverticulitis requiring multiple hospitalizations underwent laparoscopic sigmoidectomy. The early postoperative period was complicated by peritonitis, demanding an urgent "second-look" exploratory laparoscopy. Nine days post-operatively, a filiform metallic object in the upper-quadrant was noted on x-ray. No epidural had been placed for either one of her recent surgeries. Given the patient's history, the object was initially thought to be a retained surgical sponge. Previous studies, however, showed that the same image was already present preoperatively. Upon further questioning, the patient reported an epidural being placed twelve years before, at the time of her pregnancy. No mention of breakage had been made to her at that time, nor a retained foreign body was ever reported afterwards, despite her many imaging exams. She also never experienced any symptoms. A 15 cm fragment of a wire-reinforced catheter was surgically retrieved under local anesthesia and fluoroscopic guidance. CONCLUSION: Breakage of the epidural catheter with fragment retention is a known complication of this device, possibly leading to devastating sequelae. The fragment can go undetected for years. In this case our finding was incidental and the patient was asymptomatic. However, in the event a neurologic complication arose, the identification of the unknowingly retained epidural as the causative agent could have been difficult and delayed, with potential harm to the patient.

[The birthing ball: rediscovering a non pharmacological resource of great importance in the birth process]. / A pelota de parto. Redescubriendo un recurso no farmacológico de gran importancia en el proceso del parto.

Advances occurred in recent years in obstetrics show that the free movement of the pelvis during labour decreases pain and facilitates the birth of the newborn. Nowadays, many techniques have effective non pharmacological relief in pain during labour. The birthing ball (BB) is one of them, closely linked to freedom of movement, the pelvic tilt and vertical feeding; it has shown a decrease in anxiety and pain during the birthing process and increased rate of normal deliveries. The BB does not replace other non-pharmacological techniques during the period of expansion, but can complement it, thereby improving their effectiveness. Not shown any harmful effects associated with the use of the BB both the mother and the newborn. As health professionals, we must know how to use and the benefits that are associated with the BB, to offer it as an effective method of pain relief in labour available to us.

Unintentional dural puncture with a Tuohy needle increases risk of chronic headache.

BACKGROUND: Neuraxial analgesia is chosen by almost half of women who give birth in the United States. Unintentional dural puncture is the most common complication of this pain management technique, occurring in 0.4% to 6% of parturients. Severe positional headaches develop acutely in 70% to 80% of these parturients. Acute postdural puncture headaches are well known, but few studies have investigated long-term sequelae. We investigated the incidence of and risk factors for chronic headache and chronic back pain in parturients who experienced unintentional dural puncture with a 17-gauge Tuohy needle compared with matched controls. METHODS: In a case control design, 40 parturients who sustained unintentional dural puncture with a 17-gauge Tuohy needle over an 18-month period and 40 controls matched for age, weight, and time of delivery were recruited by telephone and 2 validated questionnaires were administered assessing headache and back pain symptoms 12 to 24 months after delivery. RESULTS: The incidence of chronic headaches in the study group (28%) was significantly higher than in the matched controls (5%) (OR = 7, P = 0.0129). Subjects who experienced dural punctures were more likely than controls to report chronic back pain (OR = 4, P = 0.0250), but treatment with an epidural blood patch was not a risk factor for chronic back pain. CONCLUSIONS: Patients who incur unintentional dural punctures with large-gauge needles are surprisingly likely to continue to suffer chronic headaches. Treatment with an epidural blood patch does not enhance the risk of chronic back pain. The pathophysiology underlying these symptoms and the best treatment for this syndrome are not known.

A newly developed scavenging system for administration of nitrous oxide during labour: safe occupational use.

OBJECTIVE: Nitrous oxide (N(2) O) is routinely used as an analgesic in obstetrics during labour. Epidemiological studies have linked chronic occupational exposure to N(2) O to specific health problems, including reproductive risks. Occupational exposure limits (OELs) allow the use of N(2) O once appropriate preventive and safety measures have been taken. We assessed the effectiveness of a scavenger system (Anevac P-system®, Medicvent Heinen & Löwestein Benelux, Barneveld, the Netherlands) applied in N(2) O administration during labour in a midwifery-led birthing centre in the Netherlands. METHODS: After informed consent, non-pregnant midwives were trained to administer N(2) O. N(2) O was delivered as a 50 : 50 mixture with oxygen and was self administered by the patient. The scavenging device, containing a double mask and a chin mask, was connected to the local evacuation system vented outside the building. Data on the 8-h time-weighted average (8-h TWA) as well as the 15-min TWA (15-min TWA) were obtained. RESULTS: Thirteen patients were included. Six patients were included in the first study period. In this period the 8-h TWA was not exceeded, however, in all patients, the 15-min TWA occasionally exceeded the OELs. After four additional measures, seven patients were included. After implementation of these measures, the 8-h TWA and 15-min TWA never exceeded the OELs. System leakage was not observed during both study periods. CONCLUSION: The Anevac P-scavenging system during N(2) O analgesia in labour prevents exceeding OELs in professional workers. The scavenging system appeared acceptable and effective, and can be considered in hospital settings that use N(2) O as analgesic during labour.