Effect of an oxytocin protocol on secondary uterotonic use in patients undergoing Cesarean delivery.

PURPOSE: Protocol-driven oxytocin regimens can reduce oxytocin administration compared with a nonprotocol free-flow continuous infusion. Our aim was to compare secondary uterotonic use between a modified "rule of threes" oxytocin protocol and a free-flow continuous oxytocin infusion after Cesarean delivery. METHODS: We conducted a retrospective before-and-after study to compare patients who underwent Cesarean delivery between 1 January 2010 and 31 December 2013 (preprotocol) with patients who underwent Cesarean delivery between 1 January 2015 and 31 August 2017 (postprotocol). The preprotocol group received free-flow oxytocin administration and the postprotocol group received oxytocin according to a modified rule of threes algorithm. The primary outcome was secondary uterotonic use and the secondary outcomes included blood transfusion, hemoglobin value < 8 g·dL-1, and estimated blood loss. RESULTS: In total, 4,010 Cesarean deliveries were performed in 3,637 patients (2,262 preprotocol and 1,748 postprotocol). The odds of receiving secondary uterotonic drugs were increased in the postprotocol group (odds ratio [OR], 1.33; 95% confidence interval [CI], 1.04 to 1.70; P = 0.02). Patients in the postprotocol group were less likely to receive a blood transfusion. Nevertheless, the two groups were similar for the composite end point of transfusion or hemoglobin < 8 g·dL-1 (OR, 0.86; 95% CI, 0.66 to 1.11; P = 0.25). The odds of an estimated blood loss greater than 1,000 mL were reduced in the postprotocol group (OR, 0.64; 95% CI, 0.50 to 0.84; P = 0.001). CONCLUSIONS: Patients in the modified rule of threes oxytocin protocol group were more likely to receive a secondary uterotonic than those in the preprotocol group. Estimated blood loss and transfusion outcomes were similar.

RéSUMé: OBJECTIF: Les schémas thérapeutiques d'ocytocine basés sur un protocole peuvent réduire l'administration d'ocytocine par rapport à une perfusion continue en débit libre hors protocole. Notre objectif était de comparer l'utilisation secondaires d'agents utérotoniques entre un protocole modifié d'ocytocine en « règle de trois ¼ et une perfusion continue d'ocytocine à débit libre après un accouchement par césarienne. MéTHODE: Nous avons mené une étude rétrospective avant-après pour comparer les personnes ayant bénéficié d'une césarienne entre le 1er janvier 2010 et le 31 décembre 2013 (pré-protocole) avec les personnes ayant subi une césarienne entre le 1er janvier 2015 et le 31 août 2017 (post-protocole). Le groupe pré-protocole a reçu une administration d'ocytocine en débit libre et le groupe post-protocole a reçu de l'ocytocine selon un algorithme de règle de trois modifié. Le critère d'évaluation principal était l'utilisation secondaire d'agents utérotoniques et les critères d'évaluation secondaires incluaient la transfusion sanguine, un indice d'hémoglobine < 8 g·dL­1 et les pertes de sang estimées. RéSULTATS: Au total, 4010 accouchements par césarienne ont été réalisés chez 3637 patient·es (2262 pré-protocole et 1748 post-protocole). Les chances de recevoir des médicaments utérotoniques secondaires étaient plus élevées dans le groupe post-protocole (rapport de cotes [RC], 1,33; intervalle de confiance [IC] à 95 %, 1,04 à 1,70; P = 0,02). Les patient·es du groupe post-protocole étaient moins susceptibles de recevoir une transfusion sanguine. Néanmoins, les deux groupes étaient similaires en ce qui touchait au critère d'évaluation composite de transfusion ou d'hémoglobine < 8 g·dL­1 (RC, 0,86; IC 95, 0,66 à 1,11; P = 0,25). Les risques d'une perte de sang estimée supérieure à 1000 mL ont été réduits dans le groupe post-protocole (RC, 0,64; IC 95 %, 0,50 à 0,84; P = 0,001). CONCLUSION: Les patient·es du groupe du protocole d'ocytocine en règle de trois modifiée étaient plus susceptibles de recevoir un utérotonique secondaire que les personnes du groupe pré-protocole. Les pertes sanguines estimées et les résultats transfusionnels étaient similaires.

Obstetric Anesthetic Management for Parturients with Hereditary Angioedema: A Case Report and Suggested Protocol.

Hereditary angioedema (HAE) is a disease manifested by repeated episodes of localized submucosal or subcutaneous edematous episodes, potentially triggered by emotional stress, mechanical trauma, or intake of estrogens. We present our experience managing two parturients with HAE. Multidisciplinary care is essential for planning and executing the specialized care of these patients, and management included extensive planning among obstetric, anesthesiology, and allergy and immunology teams. Pregnancy has been shown to have a variable effect on triggering HAE episodes. First-line treatment includes C1 esterase inhibitor concentrate, which can also be used for prophylaxis in high-risk patients. Neuraxial analgesia is recommended to avoid general anesthesia and was established early in both individuals. Vaginal delivery was well tolerated without need for emergent treatment for angioedema symptoms.

Effect of penicillin allergy on prophylactic antibiotic administration in the parturient undergoing cesarean delivery.

BACKGROUND: Administering antibiotics is often difficult in patients with specific medication allergies. This investigation aimed to determine if a penicillin or cephalosporin allergy increased the risk for not receiving correct timing of prophylactic antibiotics at cesarean delivery. We hypothesized that patients with a penicillin or cephalosporin allergy would be less likely to receive antibiotics prior to incision for cesarean delivery. METHODS: All women undergoing cesarean delivery at Mayo Clinic Hospital, from 1 March 2008, to 28 February 2018 were retrospectively identified by electronic medical record query. Patients were grouped based on allergy status to penicillin/cephalosporins. Data recorded included the type and time of antibiotic given in relation to surgical incision. The primary outcome of this study was administration of antibiotics within 60 minutes prior to surgical incision. Characteristics potentially associated with the primary outcome were assessed using logistic regression. RESULTS: Of the 818 patients with a penicillin or cephalosporin allergy, 75 (9.2%) did not receive prophylactic antibiotic within 60 minutes prior to skin incision. Conversely, 326 (6.9%) of the 4744 patients without a penicillin or cephalosporin allergy did not receive their prophylactic antibiotic within 60 minutes prior to skin incision (P = .019). Patients undergoing an emergent cesarean delivery were also at an increased risk of not receiving their prophylactic antibiotic within 60 minutes prior to skin incision (P < .001). CONCLUSION: Patients with a penicillin or cephalosporin allergy were less likely to receive prophylactic antibiotics within the recommended 60 minutes prior to surgical incision. Clear plans and communication are important for ensuring proper antibiotic administration at cesarean delivery to prevent surgical site infection.

Intrathecal Morphine versus Intrathecal Hydromorphone for Analgesia after Cesarean Delivery: A Randomized Clinical Trial.

BACKGROUND: Intrathecal opioids are routinely administered during spinal anesthesia for postcesarean analgesia. The effectiveness of intrathecal morphine for postcesarean analgesia is well established, and the use of intrathecal hydromorphone is growing. No prospective studies have compared the effectiveness of equipotent doses of intrathecal morphine versus intrathecal hydromorphone as part of a multimodal analgesic regimen for postcesarean analgesia. The authors hypothesized that intrathecal morphine would result in superior analgesia compared with intrathecal hydromorphone 24 h after delivery. METHODS: In this single-center, double-blinded, randomized trial, 138 parturients undergoing scheduled cesarean delivery were randomized to receive 150 µg of intrathecal morphine or 75 µg of intrathecal hydromorphone as part of a primary spinal anesthetic and multimodal analgesic regimen; 134 parturients were included in the analysis. The primary outcome was the numerical rating scale score for pain with movement 24 h after delivery. Static and dynamic pain scores, nausea, pruritus, degree of sedation, and patient satisfaction were assessed every 6 h for 36 h postpartum. Total opioid consumption was recorded. RESULTS: There was no significant difference in pain scores with movement at 24 h (intrathecal hydromorphone median [25th, 75th] 4 [3, 5] and intrathecal morphine 3 [2, 4.5]) or at any time point (estimated difference, 0.5; 95% CI, 0 to 1; P = 0.139). Opioid received in the first 24 h did not differ between groups (median [25th, 75th] oral morphine milligram equivalents for intrathecal hydromorphone 30 [7.5, 45.06] vs. intrathecal morphine 22.5 [14.0, 37.5], P = 0.769). From Kaplan-Meier analysis, the median time to first opioid request was 5.4 h for hydromorphone and 12.1 h for morphine (log-rank test P = 0.200). CONCLUSIONS: Although the hypothesis was that intrathecal morphine would provide superior analgesia to intrathecal hydromorphone, the results did not confirm this. At the doses studied, both intrathecal morphine and intrathecal hydromorphone provide effective postcesarean analgesia when combined with a multimodal analgesia regimen.

A 3-arm randomized clinical trial comparing interscalene blockade techniques with local infiltration analgesia for total shoulder arthroplasty.

BACKGROUND: The ideal analgesic modality for total shoulder arthroplasty (TSA) remains controversial. We hypothesized that a multimodal analgesic pathway incorporating continuous interscalene blockade (ISB) provides better analgesic efficacy than both single-injection ISB and local infiltration analgesia. METHODS: This single-center, parallel, unblinded, randomized clinical trial evaluated 129 adults undergoing primary TSA. Patients were allocated to single-injection ISB, continuous ISB, or local infiltration analgesia. The primary outcome was the Overall Benefit of Analgesia Score (range, 0 [best] to 28 [worst]) on postoperative day 1. Additional outcomes included pain scores, opioid consumption, quality of life, and postoperative complications in the first 24 hours, at 3 months, and at 1 year. RESULTS: We analyzed 125 patients (42 with single-injection ISB, 41 with continuous ISB, and 42 with local infiltration analgesia). The Overall Benefit of Analgesia Score was significantly improved in the continuous group (median [25th percentile, 75th percentile], 0 [0, 2]) compared with the single-injection group (2 [1, 4]; P = .002) and local infiltration analgesia group (3 [2, 4]; P < .001). Pain scores were significantly lower in the continuous group compared with the local infiltration analgesia group (P < .001 for all time points) and after 12 hours from ward arrival compared with the single-injection group (median [25th percentile, 75th percentile], 1.0 [0.0, 2.8] vs. 2.5 [0.0, 4.0]; P = .016). After postanesthesia recovery discharge, opioid consumption (oral morphine equivalents) was significantly lower in the continuous group (median [25th percentile, 75th percentile], 7.5 mg [0.0, 25.0 mg]) than in the local infiltration analgesia group (30 mg [15.0, 52.5 mg]; P < .001) and single-injection group (17.6 mg [7.5, 45.5 mg]; P = .010). No differences were found across groups for complications, 3-month outcomes, and 1-year outcomes. CONCLUSION: Continuous ISB provides superior analgesia compared with single-injection ISB and local infiltration analgesia in the first 24 hours after TSA.

Intrathecal Hydromorphone and Morphine for Postcesarean Delivery Analgesia: Determination of the ED90 Using a Sequential Allocation Biased-Coin Method.

BACKGROUND: Intrathecal (IT) morphine is considered the "gold standard" for analgesia after cesarean delivery under spinal anesthesia, most commonly administered at a dose of 100 to 200 µg. There is less experience with IT hydromorphone for postcesarean analgesia and limited information on its optimal analgesic dose. We conducted this study to determine the effective analgesic dose for 90% patients (ED90) of IT hydromorphone that provides effective analgesia for women undergoing elective cesarean delivery and its potency ratio to IT morphine. METHODS: In this dose-finding trial, 80 patients received spinal anesthesia for cesarean delivery. Participants were randomized to receive IT morphine or IT hydromorphone at a dose determined using up-down sequential allocation with a biased-coin design to determine ED90. All patients received standardized multimodal analgesia postoperatively in addition to IT opioid. An effective dose was defined as a numeric response score for pain of ≤3 (scale 0-10) 12 hours after spinal injection. RESULTS: The ED90 was 75 µg (95% confidence interval [CI], 46-93 µg) for IT hydromorphone and 150 µg (95% CI, 145-185 µg) for IT morphine. At these doses, the 95% CI for the percentage of patients with effective analgesia (numeric rating scale ≤3) was 64% to 100% for hydromorphone and 68% to 100% for morphine. Exploratory findings showed that the incidence of nausea and pruritus was not different among the most commonly used doses of IT hydromorphone (P = 0.44 and P = 0.74) or IT morphine (P = 0.67 and P = 0.38, respectively). When administering IT opioids at ED90 doses or higher, 100% (21/21) of IT hydromorphone and 95% (37/39) of IT morphine patients were satisfied with their analgesia. CONCLUSIONS: The ratio of IT morphine to IT hydromorphone for effective postcesarean analgesia is 2:1. Patient satisfaction was high with both medications.

Velamentous Umbilical Cord Insertion and Ruptured Fetal Vessel: A Cause of Fetal-Maternal Hemorrhage: A Case Report.

Background: Fetal hemorrhage is rare but can result in rapid fetal compromise. Abnormally located fetal vessels within the membranes increase the risk for their rupture and subsequent hemorrhage. The classic example of this is vasa previa. Case: We present a case of acute fetal hemorrhage resulting from a ruptured fetal vessel. During induction of labor, significant fetal heart rate deceleration occurred, coinciding with acute vaginal bleeding and amniotomy. A depressed, live female neonate was delivered by emergency cesarean section. Examination of the placenta revealed a velamentous cord insertion and a ruptured fetal vessel coursing through the chorioamniotic membranes. Neonatal resuscitation included red blood cell transfusion for hypotension and low hematocrit. The neonate made a full recovery. Conclusion: Acute fetal hemorrhage from the rupture of aberrant fetal vessels often coincides with rupture of membranes. Identifying ruptured fetal vessels abnormally coursing through the chorioamniotic membranes on examination of the placenta provides supporting evidence for suspected fetal hemorrhage.

Improvement in Accuracy and Concordance of American Society of Anesthesiologist's Physical Status (ASA-PS) Scoring Assignment over a 11 Year Time Period Using Patient BMI as a Comorbidity Finding.

Background: Anesthesia providers categorize patients utilizing the American Society of Anesthesiologists Physical Status (ASA-PS) classification originally created by the ASA in 1941. There is published variability and discordance among providers when assigning patient ASA scores in part due to the subjectivity of scoring utilizing patient medical conditions, but variability is also found using objective findings like BMI. To date, there are few studies evaluating the accuracy of anesthesia providers' ASA assignment based on objective body mass index (BMI) alone. The aim of this retrospective chart review is to determine improvement in accuracy of anesthesia providers to correctly assign patient ASA scores, based on BMI criteria added to the ASA-PS in October of 2014, utilizing a multifaceted strategy including creation of an active finance committee in the fall of 2015, multiple e-mail communications about the updated definitions and recommendations for ASA-PS scoring in the fall of 2015 and spring of 2016, a department grand rounds presentation in February 2016, placement of laminated copies of the ASA definitions and recommendations in the anesthesia chartrooms, and the development of a tool embedded into our EMR providing a recommendation of ASA-PS based on patient comorbidity findings. Methods: After attaining IRB approval, all eligible patients over the age of 18 who had surgical procedures under general anesthesia at Mayo Clinic in Rochester, MN, between January 1, 2010, and December 31, 2020, were retrospectively analyzed. A segmented logistic regression model was used to estimate the trends (per-year change in odds) of ASA under classification according to severity of obesity during 3 epochs: preimplementation (2010-2014), implementation (2015), and postimplementation (2016-2020). Results: A total of 16,467 patients of the 200,423 (8.2%) patients with obesity (class 1, 2, and 3) were underscored based on BMI alone. Accuracy of ASA-PS classification, as it pertains to BMI alone, was found to show meaningful improvement year-to-year following the updated ASA-PS guidelines with examples released in October of 2014 (P < 0.001). Most of the improvement occurred in 2015-2017 with relatively little between-year variability in the rate of underscoring from 2017-2020. Conclusion: Despite updated ASA-PS published guidelines, providers may still be unaware of the updated guidelines and inclusion of examples used within the ASA-PS classification system. Accuracy of scoring did improve annually following the release of the updated guidelines with examples as well as department-wide educational activities on the topic. Additional education and awareness should be offered to those responsible for preanesthesia evaluation and assignment of ASA-PS in patients to improve accuracy as it pertains to BMI.

Impact of nitrous oxide use on parturient recall of neuraxial analgesia risks.

STUDY OBJECTIVE: Nitrous oxide affects memory and recall. We aimed to determine if using nitrous oxide during labor affected patients' ability to learn and recall the risks and benefits of neuraxial analgesia. DESIGN: Single-center, prospective cohort study. SETTING: Labor and delivery unit in a large academic medical center. PATIENTS: Nulliparous patients with spontaneous or planned induction of labor. INTERVENTIONS: Parturients chose whether to use nitrous oxide during labor. At the discussion for epidural consent, 4 risks were described: headache, infection, nerve damage, bleeding. MEASUREMENTS: Labor pain score, time from nitrous oxide discontinuation, and cervical dilation were documented at the discussion of epidural risks. Patients were assessed for unprompted recall and prompted recall of epidural risks on postpartum day 1 and unprompted recall at postpartum week 6. The number and proportion of patients who indicated each true risk (unprompted and prompted recall) or distractor (prompted recall only) were summarized by treatment group and results compared using Pearson χ2 tests. MAIN RESULTS: Of the 403 enrolled patients, 294 (73%) did not use nitrous oxide, and 109 (27%) did. The 2 groups were similar except women who used nitrous oxide were more likely to be cared for by midwives and had higher pain scores at their epidural request. Scores for unprompted or prompted recall of epidural risks were not different between women who received or did not receive nitrous oxide. All 4 risks were recalled unprompted by only 3% in the nitrous oxide group and by 6% in the group not receiving nitrous oxide (P = .18). CONCLUSIONS: The use of nitrous oxide for labor analgesia does not adversely influence a parturient's ability to recall the risks of epidural placement. Patients who receive nitrous oxide for labor analgesia should be considered eligible to provide consent for subsequent procedures.

Needle echogenicity in sonographically guided regional anesthesia: blinded comparison of 4 enhanced needles and validation of visual criteria for evaluation.

OBJECTIVES: Needle visualization is important for sonographically guided regional anesthesia procedures. Needle characteristics that improve needle visualization are therefore important to anesthesiologists. This study compared several echogenic needle designs by defining characteristics of needle echogenicity and assessing regional anesthesiologist preferences for these characteristics across various needle angles. METHODS: Twelve blinded regional anesthesiologists graded 5 randomized block needles (1 nonechogenic control and 4 echogenic) on 4 predefined characteristics (overall brightness of the needle, overall clarity of the needle, brightness of the needle tip, and clarity of the needle tip). In-plane needle images in a gel phantom were obtained at 4 needle angles (15°, 30°, 45°, and 60°). Participants rated specific needle characteristics for each needle at each angle and then ranked their overall needle preferences. RESULTS: Significant differences in all 4 needle characteristics were found across needle types (P< .01). Clarity of the needle tip was significantly associated with overall needle rank (P = .009). Other needle visualization characteristics were not significantly correlated with needle rank. The SonoPlex Stim needle (Pajunk Medical Systems, Tucker, GA) was rated highest in all 4 predefined needle characteristics as well as overall needle rank. CONCLUSIONS: This study shows that anesthesiologists prefer certain visual characteristics of needles used in sonographically guided regional anesthesia procedures. Specifically, needle tip clarity most closely predicted clinician needle preferences. These results support the idea that all echogenic needle designs do not uniformly enhance needle visualization. Further studies are needed to determine whether needles with superior tip clarity predict not only clinician preferences but also improved sonographically guided regional anesthetic outcomes.

Simulation Training Effects on Resident-Perceived Readiness for Obstetric Anesthesia Rotation.

Background: Beginning an unfamiliar rotation can be challenging as residents must expand their knowledge and skills to meet new clinical expectations, work with a new team of providers, and sometimes care for a new patient demographic. This may detract from learning, resident well-being, and patient care. Methods: We implemented an obstetric anesthesia simulation session for anesthesiology residents prior to their first obstetric anesthesia rotation and measured the effect on residents' self-perceived preparedness. Results: The simulation session increased residents' feelings of preparedness for the rotation and increased residents' confidence in specific obstetric anesthesia skills. Conclusions: Importantly, this study shows the potential for the use of a prerotation, rotation-specific simulation session to better prepare learners for rotations.

Retrospective Review of Intrathecal Hydromorphone Dose Range and Complications.

BACKGROUND: Optimal intrathecal dosing regimens for hydromorphone are not well established for analgesia after abdominal surgery. OBJECTIVES: We reviewed intrathecal hydromorphone doses and complications because dosing variability has been observed among anesthesiologists. We hypothesized that increasing doses of intrathecal hydromorphone would be associated with improved postoperative analgesia, but with increased rates of opioid-related adverse events. STUDY DESIGN: Retrospective analysis. SETTING: A high-volume academic referral center in the United States. METHODS: A retrospective study was conducted of adults undergoing abdominal surgery under general anesthesia supplemented preoperatively with intrathecal hydromorphone for postoperative analgesia from May 5, 2018, through May 31, 2021. Patients were categorized into 3 hydromorphone dosing groups: low-dose (50-100 µg), middle-dose (101-199 µg), and high-dose (200-300 µg). Multivariable logistic regression models were used to assess rates of severe postoperative pain, severe opioid-related adverse events, oversedation, and pruritus in the postanesthesia care unit (PACU) and within 24 hours after PACU discharge. RESULTS: Of 1,846 patients identified, 1,235 (66.9%) were in the low-dose group; 321 (17.3%), middle-dose group; and 290 (15.7%), high-dose group. Patients receiving the 2 higher doses had more extensive procedures. An unadjusted analysis showed differing rates of severe pain in the PACU by group: 306 (24.8%) in the low-dose, 73 (22.7%) middle-dose, and 45 (15.5%) in the high-dose group (P = 0.003); these differences, however, were no longer significant after an adjusted analysis (P = 0.34). Ten severe opioid-related events occurred; all were recognized in the PACU. Five events each occurred in the low-dose and high-dose groups versus none in the middle-dose group (P = 0.02). No other differences were identified with adjusted analyses. LIMITATIONS: Limitations of our study include its retrospective design and its conduct at a single center, along with the apparent, but difficult to characterize, treatment biases in hydromorphone dosing. CONCLUSIONS: No dose response was observed between intrathecal hydromorphone dose and postoperative analgesia, a finding that may reflect treatment bias. Higher rates of severe opioid-related events were detected for patients receiving high-dose hydromorphone in the PACU, but all other safety outcomes were similar between dosing regimens. KEY WORDS: Drug-related side effects, opioid analgesics, outcome assessment, postoperative pain, spinal injections.

Perioperative nerve injury after total hip arthroplasty: regional anesthesia risk during a 20-year cohort study.

BACKGROUND: Perioperative nerve injury (PNI) is a recognized complication of total hip arthroplasty (THA). Regional anesthesia (RA) techniques may increase the risk of neurologic injury. Using a retrospective cohort study, the authors tested the hypothesis that use of RA increases the risk for PNI after elective THA. METHODS: All adult patients who underwent elective THA at Mayo Clinic during a 20-yr period were included. The primary outcome was the presence of a new PNI within 3 months of surgery. Multivariable logistic regression was used to evaluate patient, surgical, and anesthetic risk factors for PNI. RESULTS: Of 12,998 patients undergoing THA, 93 experienced PNI (incidence = 0.72%; 95% CI 0.58-0.88%). PNI was not associated with type of anesthesia (OR = 0.72 for neuraxial-combined vs. general; 95% CI 0.46-1.14) or peripheral nerve blockade (OR = 0.65; 95% CI 0.34-1.21). The risk for PNI was associated with younger age (OR = 0.79 per 10-yr increase; 95% CI 0.69-0.90), female gender (OR = 1.72; 95% CI 1.12-2.64), longer operations (OR = 1.10 per 30-min increase; 95% CI 1.03-1.18) or posterior surgical approach (OR = 1.91 vs. anterior approach; 95% CI 1.22-2.99). Neurologic recovery was not influenced by the use of RA techniques in patients with PNI. CONCLUSIONS: The risk for PNI after THA was not increased with the use of neuraxial anesthesia or peripheral nerve blockade. Neurologic recovery in patients who experienced PNI was not affected by the use of RA. These results support the use of RA techniques in patients undergoing elective THA given their known functional and clinical benefits.

Perioperative nerve injury after total knee arthroplasty: regional anesthesia risk during a 20-year cohort study.

BACKGROUND: Perioperative nerve injury (PNI) is one of the most debilitating complications after total knee arthroplasty (TKA). Although regional anesthesia (RA) techniques reduce pain and improve functional outcomes after TKA, they may also contribute to PNI. The objective of this study was to test the hypothesis that PNI risk differs among patients according to RA use during TKA. METHODS: All patients aged at least 18 yr who underwent elective TKA from January 1988 to July 2007 were retrospectively identified. The primary outcome variable was the presence of a new PNI documented within 3 months of the procedural date. Age, sex, body mass index, type of procedure, tourniquet time, type of anesthesia, and use of peripheral nerve blockade were evaluated as potential risk factors for PNI using multivariable logistic regression. RESULTS: Ninety-seven cases of PNI were identified among 12,329 patients. Overall incidence of PNI was 0.79% (95% CI, 0.64-0.96%). PNI was not associated with peripheral nerve blockade (odds ratio [OR], 0.97) or type of anesthesia (OR, 1.10 [neuraxial vs. general]; OR, 1.82 [combined vs. general]). Risk for PNI decreased with age (OR, 0.68 [per decade]; P < 0.001) but increased with tourniquet time (OR, 1.28 [per 30-min increase]; P = 0.003) and bilateral procedures (OR, 2.51; P < 0.001). Patients with PNI who underwent peripheral nerve blockade were less likely to have complete neurologic recovery (OR, 0.37; P = 0.03). CONCLUSIONS: Risk for PNI after TKA was unchanged by the use of RA techniques. This finding supports the notion that the known benefits of RA for patients undergoing TKA can be achieved without increasing risk of neurologic injury. However, in rare situations when PNI occurs, complete recovery may be less likely if it develops after peripheral nerve blockade.

Perioperative complications in patients with left ventricular non-compaction.

BACKGROUND AND OBJECTIVE: Left ventricular non-compaction (LVNC) is a relatively uncommon cardiomyopathy. The implications of the presence of LVNC in the perioperative period are unknown. The objective of this study was to determine the impact of LVNC on post-operative complications. METHODS: This retrospective cohort study identified patients with an echocardiographic diagnosis of LVNC who had an anaesthetic between 2001 and 2008. For each patient, all surgical procedures during this time were reviewed. Patient demographics, echocardiographic data, details of the procedure and anaesthetic and perioperative complications were recorded. We then compared the rate of perioperative complications in patients with LVNC with established complication rates in the existing literature. RESULTS: During the study period, 60 patients with LVNC underwent 220 procedures. Nineteen patients experienced a total of 25 complications, of which eight were directly related to the procedure and considered unrelated to LVNC. Of the remaining 17 complications (in 15 patients), there were 10 new arrhythmias, five respiratory complications, one seizure and one episode of syncope. Nearly half (47%) of the complications followed open cardiac surgery with cardiopulmonary bypass. All complications occurred in association with procedures performed under general anaesthesia; none occurred in patients undergoing regional anaesthesia or monitored anaesthesia care (sedation). There was no long-term morbidity and no peri-operative mortality. CONCLUSION: As the awareness and diagnosis of this condition increase, anaesthesiologists will probably care for growing numbers of patients with LVNC. We found that the incidence of post-operative complication in patients with LVNC undergoing a variety of procedures was low and no different from the published complication rates for other patients undergoing similar procedures.

Intravenous Dexmedetomidine as an Adjunct to Neuraxial Anesthesia in Cesarean Delivery: A Retrospective Chart Review.

BACKGROUND: Dexmedetomidine is a selective α-2 agonist commonly used for sedation that has been used in obstetric anesthesia for multimodal labor analgesia, postcesarean delivery analgesia, and perioperative shivering. This study evaluated the role of intravenous dexmedetomidine to provide rescue analgesia and/or sedation during cesarean delivery under neuraxial anesthesia. METHODS: We conducted a single-center, retrospective cohort study of all parturients undergoing cesarean delivery under neuraxial anesthesia between December 1, 2018, and November 30, 2019, who required supplemental analgesia during the procedure. Patients were divided into two groups: patients who received intravenous dexmedetomidine (Dexmed group) and patients who received adjunct medications such as fentanyl, midazolam, ketamine, and nitrous oxide (Standard group). Primary outcome was incidence of conversion to general anesthesia. RESULTS: During the study period, 107 patients received adjunct medications. There was no difference in conversion to general anesthesia between the Dexmed group and the Standard group (6% (4/62) vs. 9% (4/45); p=0.718). In the Dexmed group, the mean dexmedetomidine dose received was 37 µg (range 10 to 140 µg). While the use of inotropic/vasopressor medications was common and similar in both groups, there was an increase in the incidence of bradycardia (Dexmed 15% vs. Standard 2%; p=0.042) but not hypotension (Dexmed 24% vs. Standard 24%; p=1.00) in the Dexmed group. CONCLUSION: In patients who required supplemental analgesia for cesarean delivery, those who received dexmedetomidine versus other medications had a similar rate of conversion to general anesthesia, a statistically significant increase in bradycardia, but no difference in the incidence of hypotension.

Complication rate of ultrasound-guided paravertebral block for breast surgery.

BACKGROUND AND OBJECTIVES: Thoracic paravertebral blockade is often used as an anesthetic and/or analgesic technique for breast surgery. With ultrasound guidance, the rate of complications is speculated to be lower than when using landmark-based techniques. This investigation aimed to quantify the incidence of pleural puncture and pneumothorax following non-continuous ultrasound-guided thoracic paravertebral blockade for breast surgery. METHODS: Patients who received thoracic paravertebral blockade for breast surgery were identified by retrospective query of our institution's electronic database over a 5-year period. Data collected included patient demographics, level of block, type and volume of local anesthetic, occurrence of pleural puncture, occurrence of pneumothorax, evidence of local anesthetic toxicity, and patient vital signs. The incidence of block complications, including pleural puncture, pneumothorax, and local anesthetic toxicity, were ascertained. RESULTS: 529 patients underwent 2163 thoracic paravertebral injections. Zero pleural punctures were identified during block performance; however, two patients were found to have a pneumothorax on postoperative chest X-ray (3.6 per 1000 surgeries, 95% CI 0.5 to 13.6; 0.9 per 1000 levels blocked, 95% CI 0.1 to 3.3). There were no cases of local anesthetic systemic toxicity or associated lipid emulsion therapy administration. CONCLUSIONS: Pneumothorax following non-continuous ultrasound-guided thoracic paravertebral block using a parasagittal approach is an uncommon occurrence, with a similar rate to pneumothorax following breast surgery alone.

In Utero Restoration of Hindbrain Herniation in Fetal Myelomeningocele as Part of Prenatal Regenerative Therapy Program at Mayo Clinic.

OBJECTIVE: To assess our initial experience with prenatal restoration of hindbrain herniation following in utero repair of myelomeningocele (MMC). PATIENTS AND METHODS: Three consecutive patients with prenatally diagnosed MMC (between January 1, 2018 and September 30, 2018) were managed with open in utero surgery. As per institutional review board approval and following a protocol designed at the Mayo Clinic Maternal & Fetal Center, fetal intervention was offered between 19 0/7 and 25 6/7 weeks of gestation. Prenatal improvement of hindbrain herniation was the declared restorative end point. Obstetrical and perinatal outcomes were also assessed. RESULTS: Diagnosis of MMC was confirmed upon referral between 20 and 21 weeks' gestation by using fetal ultrasound and magnetic resonance imaging. In all cases reported here, the spinal defect was lumbosacral with evidence of hindbrain herniation. Open in utero MMC repair was performed between 24 and 25 weeks' gestation with no notable perioperative complications. Postprocedure fetal magnetic resonance imaging performed 6 weeks after in utero repair documented improvement of hindbrain herniation. Deliveries were at 37 weeks by cesarean section without complications. Most recent postnatal follow-ups were unremarkable at both 11 months (baby 1) and 3 months of age (baby 2), with mild ventriculomegaly. Antenatal and postnatal follow-up of baby 3 at 1 month of age was also unremarkable. CONCLUSION: Our study highlights the prenatal restoration of hindbrain herniation following in utero MMC repair in all cases presented here as an example of a prenatal regenerative therapy program in our institution.