Anesthetic and obstetric outcomes in morbidly obese parturients: a 20-year follow-up retrospective cohort study

Novel approaches facilitating neuraxial anesthesia placement in pregnant women with morbid obesity: case descriptions

Clinical management of pregnant women with morbid obesity poses challenges in performing neuraxial anesthesia as well as positioning for cesarean delivery. Occupational injuries are also known to occur while caring for patients with morbid obesity. We describe two novel approaches to assist neuraxial anesthesia administration and positioning for cesarean delivery. With the assistance of the Institution's Safe Patient Handling and Mobility Team, a universal high-back sling can be placed to lift the patient into a sitting position before neuraxial anesthesia procedure. After placement of combined spinal epidural anesthesia, the ceiling lift is used to lift the patient into a seated position and then rotate to the appropriate location on the operating room table to facilitate supine positioning. The lifting system reduces shearing of the patient's posterior and compromising the epidural site. Team members also report reduced effort required when positioning patients from seated to supine on the operating room table. The second approach is the application of TraxiTM abdominal pannus retractor to retract fat folds encroaching on the epidural placement site in pregnant women with morbid obesity. This is particularly useful when the traditional taping of fat folds away from the site is inadequate. The pannus retractor results in a flatter surface facilitating epidural placement. We have introduced these two approaches into our clinical practice for pregnant women with morbid obesity requiring cesarean delivery under neuraxial anesthesia.

The 90% effective dose of intrathecal hyperbaric bupivacaine for Cesarean delivery under combined spinal-epidural anesthesia in parturients with super obesity: an up-down sequential allocation study

PURPOSE

To determine the 90% effective dose (ED90) of intrathecal hyperbaric bupivacaine for Cesarean delivery under combined spinal-epidural anesthesia (CSE) in parturients with super obesity (body mass index [BMI] ≥ 50 kg·m-2).

METHODS

We enrolled parturients with BMI ≥ 50 kg·m-2 with term, singleton vertex pregnancies undergoing elective Cesarean delivery under CSE. An independent statistician generated the 0.75% hyperbaric bupivacaine dosing regimen in increments of 0.75 mg using a biased-coin up-down sequential allocation technique. This was combined with 15 μg fentanyl, 150 μg morphine, and normal saline to a volume of 2.05 mL. The initial and maximum doses were 9.75 mg and 12 mg, respectively. Participants, clinical team, and outcome assessors were blinded to the dose. The primary outcome was block success, defined as T6 block to pinprick within ten minutes and no intraoperative analgesic supplementation within 90 min of spinal injection. We determined the ED90 using logistic regression.

RESULTS

We enrolled 45 parturients and included 42 in the analysis. All doses achieved a T6 level within ten minutes, and the primary outcome occurred in 0/1 (0%) of the 9.75-mg doses, 2/3 (67%) of the 10.5-mg doses, 21/27 (78%) of the 11.25-mg doses, and 11/11 (100%) of the 12-mg doses. The ED90 of hyperbaric bupivacaine was 11.56 mg (95% confidence interval, 11.16 to 11.99). Four parturients (9.5%) had sensory level higher than T2, but none was symptomatic or required general anesthesia.

CONCLUSION

The estimated ED90 of hyperbaric bupivacaine with fentanyl and morphine in parturients with super obesity undergoing Cesarean delivery under CSE was approximately 11.5 mg.

STUDY REGISTRATION

ClinicalTrials.gov (NCT03781388); first submitted 18 December 2018.

Obesity at term: What to consider? How to deliver?

Obesity presents significant challenges during pregnancy, increasing the risk of complications and adverse outcomes for both mother and baby. With the rising prevalence of obesity among pregnant women, questions arise regarding optimal management, including timing of delivery and choice of delivery mode. Labour induction in obese women may require a combination of mechanical and pharmacological methods due to increased risk of failed induction. Caesarean section in obese women presents unique challenges, requiring comprehensive perioperative planning and specialized care to optimize outcomes. However, specific guidelines tailored to obese patients undergoing caesarean sections are lacking. Postpartum care should include vigilant monitoring for complications. Addressing obesity in pregnancy necessitates a multidisciplinary approach and specialized care to ensure the best outcomes.

Case report: Maternal cardiac arrest at 12 hours postpartum

Maternal cardiac arrest is a rare occurrence. In this case report, we present a detailed account of a 37-year-old pregnant woman with preeclampsia with severe features who underwent cesarean delivery. The patient experienced dyspnea and hypoxia at 12 hours postpartum, leading to cardiac arrest in the maternity ward. Advanced cardiac life support measures, including 15 minutes of chest compressions, were performed until spontaneous circulation was restored. This study explores the underlying factors contributing to maternal cardiac arrest during the postpartum period. Additionally, it highlights the effective strategies employed by our multidisciplinary team in managing and resolving this critical medical event.

Comparison of perioperative outcomes and anesthetic-related complications of morbidly obese and super-obese parturients delivering by cesarean section

OBJECTIVE

To compare the perioperative outcomes and anesthetic-related complications of morbidly obese and super-obese parturients delivering by cesarean section.

METHODS

A retrospective analysis of 6 years of data was performed. Exclusions were cases with gestational ages <24 weeks, placenta accreta spectrum, polyhydramnios, or multiple gestations.

RESULTS

The study included 494 patients whose body mass index (BMI) exceeded 40 kg/m² at delivery. Of these, 469 were morbidly obese (BMI 40-49.9; mean, 42.9 ± 2.4), and 25 were super obese (BMI >50; mean, 54.5 ± 4.2). Twenty-four (5.1%) morbidly obese women received general anesthesia. The other 445 patients (94.9%) in the morbid obesity group underwent cesarean delivery under regional anesthesia; however, some (2.2%; 10/445) received general anesthesia after regional anesthesia failed. In the super-obesity group, 23 patients (92.0%) received regional anesthesia, while two patients (8.0%) received general anesthesia. There were no cases of pulmonary aspiration, maternal deaths, or difficult or failed intubation. There was one episode of cardiac arrest in a patient with a BMI of 47.9. Among the morbidly obese and super-obese women given regional anesthesia, the super-obese patients had significantly greater volumes of ephedrine and norepinephrine consumption (p = 0.027 and 0.030), intravenous fluids (p = 0.006), and bleeding during surgery (p = 0.017). They also had more hypotensive episodes (p = 0.038). The two groups' incidences of neonatal birth asphyxia, postpartum hemorrhage, blood transfusion, and uterine atony did not differ significantly. The lengths of stay in the hospital were also comparable.

CONCLUSIONS

Among the women receiving regional anesthesia, the super-obese parturients had greater intraoperative bleeding, a higher proportion of hypotensive episodes, and a greater vasopressor requirement than the morbidly obese parturients. Anesthesiologists must prepare for the adverse perioperative events that such women risk experiencing during a delivery by cesarean section.

www.clinicaltrials.gov ID: NCT04657692.

Anesthesia and Analgesia for the Obese Parturient

Obesity is a worldwide epidemic and is associated with an increased risk of hypertension, diabetes, and obstructive sleep apnea. Pregnant patients with obesity experience a higher risk of maternal and fetal complications. Anesthesia also poses higher risks for obese parturients and may be more technically challenging due to body habitus. Safe anesthesia practice for these patients must take into consideration the unique challenges associated with the combination of pregnancy and obesity.

Vaginal Dinoprostone Insert versus Cervical Ripening Balloon for Term Induction of Labor in Obese Nulliparas-A Randomized Controlled Trial

Data regarding the preferred induction method in women with obesity is scarce. The current study was aimed at comparing pharmacological and mechanical induction in this population. This prospective randomized controlled trial was conducted between 2016−2020, in nulliparas with a pre-pregnancy body mass index >30. Inclusion criteria were singleton-term pregnancies, bishop score < 5, and indication for induction. Patients were randomized to induction by a cervical ripening balloon (CRB) or a 10 mg vaginal dinoprostone insert. The primary outcome was delivery rate within 24 h. Secondary outcomes included time to delivery, cesarean section rate, maternal and neonatal outcomes, satisfaction, and anxiety. The study population comprised of 83 women in the CRB group and 81 in the dinoprostone group. There was a significant difference in delivery rates within 24 h and time to delivery between the dinoprostone and CRB groups (45% vs. 71%, p = 0.017 and 49.3 ± 6.8 h vs. 23.5 ± 5.9 h, p = 0.003, respectively). There were no differences in cesarean delivery rates or maternal and neonatal outcomes, though CRB induction was associated with a significantly lower rate of tachysystole. Induction with CRB was accompanied by higher satisfaction and lower anxiety. In summary, CRB induction is associated with shorter time to delivery, higher satisfaction, and lower anxiety compared to PGE2 in women with obesity, without compromising maternal or neonatal outcomes.

Effect of maternal body mass index on the prophylactic dose of phenylephrine for preventing hypotension in parturients after spinal anaesthesia

BACKGROUND

To compare the median effective dose (ED₅₀) of phenylephrine for prophylactic continuous infusion in parturients with different body mass indices (BMIs) during combined spinal-epidural anaesthesia for caesarean section and to investigate the impact of maternal BMI on the prophylactic dose of phenylephrine.

METHODS

Parturients receiving combined spinal-epidural anaesthesia for elective caesarean section were divided into a standard group (Group S, BMI < 30 kg/m²) and an obesity group (Group O, BMI > 30 kg/m²), each with 30 patients. A sequential allocation design was used to administer the prophylactic infusion of phenylephrine after the completion of a spinal anaesthetic injection to prevent hypotension (defined as a reduction of systolic blood pressure ≥ 20% of the baseline value or systolic blood pressure < 90 mmHg), with an initial infusion rate of 50 μg/min for the first parturient subsequent adjusted up or down by 10 μg/min depending on whether the previous parturient developed hypotension or not during the study period. The Dixon and Massey method and the isotonic regression method were used to calculate and compare the ED₅₀ and 95% confidence interval (CI) of phenylephrine between the two groups.

RESULTS

The results were 21.92 μg/min (95% CI, 14.90-28.94 μg/min) for Group S and 42.14 μg/min (95% CI, 24.58-59.70 μg/min) for Group O. The ratio of relative potency of Group O to Group S is 1.92 (95% CI 1.09 - 3.14), P = 0.034.

CONCLUSIONS

The dose of phenylephrine for the prevention of hypotension after spinal anaesthesia for caesarean section is dependent on maternal BMI. Therefore, a weight-based phenylephrine dose is reasonable.

Pregnancy Care for Patients With Super Morbid Obesity

The patient with obesity represents unique challenges to the medical community and, in the setting of pregnancy, additional risks to both mother and fetus. This document will focus on the risks and considerations needed to care for the women with obesity and her fetus during the antepartum, intrapartum, and immediate postpartum stages of pregnancy. Specific attention will be given to pregnancy in the setting of class III and super morbid obesity.

Induction of labour in pregnant individuals with obesity

People with obesity may require induction of labour (IoL) due to a higher incidence of pre-existing comorbidities and pregnancy complications, as well as to prevent post-term pregnancies and late-term stillbirths. IoL at 39-40 weeks is associated with fewer caesarean births and lower morbidity for the pregnant person and neonate when compared with expectant management. Ensuring the success and safety of IoL in people with obesity requires adherence to evidence-based protocols for the management of labour induction and augmentation. Cervical ripening as well as the latent and active phases of labour in people with obesity may be considerably prolonged, requiring higher cumulative doses of oxytocin. This should be guided by intrauterine pressure catheters and early provision of neuraxial analgesia, where possible. There is insufficient evidence to recommend one method of IoL over another. The need for higher doses of prostaglandins and concurrent agents for cervical ripening should be studied in prospective studies.

Analgesic considerations for induction of labor

Induction of labor may be indicated to minimize maternal and fetal risks. The rate of induction is likely to increase as recent evidence supports elective induction at 39 weeks gestation. We review methods of induction and then analgesic options as they relate to indications and methods to induce labor. We specifically focus on parturients at high risk for anesthetic complications including those requiring anticoagulation, and those with cardiac disease, obesity, chorioamnionitis, prior spinal instrumentation, elevated intracranial pressure, known or anticipated difficult airway, thrombocytopenia, and preeclampsia. Guidelines regarding timing of anticoagulation dosing with neuraxial anesthetic techniques have been defined through consensus statements. Early epidural placement may be beneficial in patients with cardiac disease, obesity, anticipated difficult airway, and HELLP syndrome. Questions remain regarding how early is too early for epidural placement, what options are safest for patients with bacteremia, and what pain relief should be offered to those unable to tolerate cervical exams in early labor.

Cesarean Delivery in a Patient With Body Mass Index Over 100: Continuous Spinal Anesthesia in Two Consecutive Deliveries

Anesthetic implications for morbidly obese parturients have been well described; however, the literature has not yet clarified whether there are additional or unique concerns if the body mass index (BMI) rises farther above the so-called super morbid obesity level: BMI >50 kg/m². There have only been a few case reports focusing on patients with BMI close to or above 100. Parturients with BMI significantly greater than 50 are uncommon, but they represent an increasing proportion among the morbidly obese. In this report, we present the use of continuous spinal anesthesia in consecutive cesarean deliveries for a patient with a BMI of 102 at her first delivery and 116 at her second. For both deliveries, an intrathecal catheter dosing incrementally provided effective anesthesia with a cumulative dose of hyperbaric bupivacaine 12 mg, fentanyl 15 mcg, and morphine 100 mcg given in 0.25-ml increments over 12 minutes, with 0.25-ml sterile saline flushes between doses. While dosing the catheter, the patient was gradually lowered to a 30° semi-recumbent position for surgery. This strategy minimized the risk of high spinal block or respiratory distress. She did not develop any postdural puncture headache (PDPH). This case report offers an extreme example and provides estimates towards adjusting staffing, equipment, location, timing, positioning, anesthetic technique, and dosing for cesarean deliveries in patients with very high BMI levels.

Neuraxial labor analgesia failure rates in women with a body mass index ≥50 kg/m2: a single-center retrospective study

BACKGROUND

The failure rate of neuraxial labor analgesia has not been investigated in super-obese women (body mass index ≥50 kg/m²).

METHODS

We performed a retrospective study of neuraxial labor analgesia in super-obese women (January 2012 to August 2019). The primary outcome was the failure rate of the first neuraxial catheter. Secondary outcomes were failure rates by neuraxial technique, at cesarean delivery, and rate of catheter replacement.

RESULTS

Neuraxial labor analgesia was used by 233 super-obese women: 153 epidural catheters placed using a combined spinal-epidural (CSE) or dural puncture epidural techniques with visualization of cerebrospinal fluid; 63 placed without dural puncture (including procedures without attempted dural puncture or attempted CSE or dural puncture epidural); and 17 intrathecal catheters (seven intentional). Thirty-two of 233 neuraxial catheters failed (13.7%, 95% Confidence Interval [CI] 9.9 to 18.7%). Epidural catheters placed using CSE or dural puncture epidural had a lower failure rate than those placed without dural puncture (9.2% [95% CI 5.5% to 14.7%] vs 28.6% [95% CI 18.9 to 40.7%]; P<0.001). Catheter migration was documented for 29.4% (95% CI 16.8 to 46.2%) of catheters that failed.

CONCLUSIONS

Epidural catheters placed using CSE or dural puncture epidural techniques were more reliable than those placed without dural puncture in super-obese parturients. It is unclear whether the result was driven by grouping procedures without attempted dural puncture with those in which dural puncture was attempted but cerebrospinal fluid was not obtained. Catheter migration was a major source of failure.

Epidural analgesia in the obese obstetric patient: a retrospective and comparative study with non-obese patients at a tertiary hospital

BACKGROUND AND OBJECTIVES

Obesity is becoming a frequent condition among obstetric patients. A high body mass index (BMI) has been closely related to a higher difficulty to perform the neuraxial technique and to the failure of epidural analgesia. Our study is aimed at analyzing obese obstetric patients who received neuraxial analgesia for labor at a tertiary hospital and assessing aspects related to the technique and its success.

METHODS

Retrospective observational descriptive study during one year. Women with a BMI higher than 30 were identified, and variables related to the difficulty and complications of performing the technique, and to analgesia failure rate were assessed.

RESULTS AND CONCLUSIONS

Out of 3653 patients, 27.4% had their BMI ≥ 30 kg.m-². Neuraxial techniques are difficult to be performed in obese obstetric patients, as showed by the number of puncture attempts (≥ 3 in 9.1% obese versus 5.3% in non-obese being p < 0.001), but the incidence of complications, as hematic puncture (6.6%) and accidental dural puncture (0.7%) seems to be similar in both obese and non-obese patients. The incidence of cesarean section in obese patients was 23.4% (p <  0.001). Thus, an early performance of epidural analgesia turns out to be essential to control labor pain and to avoid a general anesthesia in such high-risk patients.

Obesity and Pregnancy

The worldwide rates of obesity have increased significantly in recent decades. In the United States, more than 50% of pregnant women are overweight or obese. Obese gravid women are more prone to adverse pregnancy outcomes, including gestational diabetes, hypertensive disorders, and cardiovascular diseases. The adverse outcomes extend beyond the pregnant obese woman; offspring of obese women are themselves at increased risk of prematurity, fetal death, injury during birth, and transient respiratory problems and metabolic effects (ie, neonatal hypoglycemia). Furthermore, maternal obesity can predispose their offspring to long-term health problems, potentially generating an intergenerational cycle of obesity and insulin resistance.

Considering Labor After Cesarean in a Woman with Class 3 Obesity

Because of the high cesarean rate in the United States, perinatal care providers are increasingly called upon to counsel women considering labor after cesarean. This counseling can be more complicated for women with class 3 obesity, defined as a body mass index at or exceeding 40. Although labor after cesarean may be less likely to result in successful vaginal birth after cesarean (VBAC) for this population, the risks of repeat cesarean are also higher for these women. This case report describes the benefits and risks of labor after cesarean, the chance of successful VBAC, and clinical recommendations to aid women in achieving VBAC when class 3 obesity is present.

Obstetric pain correlates with postpartum depression symptoms: a pilot prospective observational study

BACKGROUND

Data linking labor pain and postpartum depression are emerging. Robust, prospective evaluations of this relationship while factoring other important variables are lacking. We assessed perinatal pain and other factors predicting postpartum depression (PPD) symptoms.

METHODS

Third trimester women, stratified by a priori plan to receive or avoid labor epidural analgesia, were longitudinally followed from the prenatal period through labor and delivery, until 6 weeks and 3 months postpartum. Electronic pain data was collected hourly during labor in real time, capturing pain unpleasantness, intensity, pain management satisfaction, and expectations. Prenatal and postpartum data included anxiety, depression, the Brief Pain Inventory (BPI), pain catastrophizing, resiliency, and perceived social support and stress. The primary outcome was Edinburgh Postnatal Depression Score (EPDS) as a marker of PPD symptoms. The primary pain variable of interest was labor pain emotional valence (unpleasantness burden, area under the curve for entire labor duration). Single and multivariable linear regressions examined perinatal pain variables in relation to EPDS.

RESULTS

Of 72 subjects included, 55 planned/received labor epidural analgesia and 17 planned avoidance/avoided it. In the planned epidural group, the emotional valence of labor pain independently predicted six-week EPDS (labor pain unpleasantness burden, R² = 0.42, P = 0.002). In addition to labor pain, prenatal and postpartum pain variables from the BPI independently predicted six-week EPDS. Three-month depression scores were linked to labor and acute pain (6 weeks postpartum), but not to chronic (3 months postpartum) pain variables. Intrapartum pain management satisfaction and expectations were largely met or exceeded and did not differ between analgesia groups.

CONCLUSION

For susceptible women, pain at all perinatal time points-prenatal, labor, and postpartum-appear to be independently linked to depression scores at 6 weeks postpartum. The relationships are true, even though satisfaction and expectations regarding labor pain management were met or exceeded. These data support the concept that labor and acute postpartum pain influences both acute and long-term PPD symptoms, although additional data are needed to assess how analgesia preference interacts with these relationships.

Obesity And Obstetric Anesthesia: Current Insights

Obesity is a significant global health problem. It results in a higher incidence of complications for pregnant women and their neonates. Cesarean deliveries are more common in obese parturients as well. The increased burden of comorbidities seen in this population, such as obstructive sleep apnea, necessitates antepartum anesthetic consultation. These patients pose unique challenges for the practicing anesthesiologist and may benefit from optimization prior to delivery. Complications from anesthesia and overall morbidity and mortality are higher in this population. Neuraxial anesthesia can be challenging to place in the obese parturient, but is the preferred anesthetic for cesarean delivery to avoid airway manipulation, minimize aspiration risk, prevent fetal exposure to volatile anesthetic, and decrease risk of post-partum hemorrhage from volatile anesthetic exposure. Monitoring and positioning of these patients for surgery may pose specific challenges. Functional labor epidural catheters can be topped up to provide conditions suitable for surgery. In the absence of a working epidural catheter, a combined spinal epidural anesthetic is often the technique of choice due to relative ease of placement versus a single shot spinal technique as well as the ability to extend the anesthetic through the epidural portion. For cesarean delivery with a vertical supraumbilical skin incision, a two-catheter technique may be beneficial. Concern for thromboembolism necessitates early mobilization and a multimodal analgesic regimen can help accomplish this. In addition, thromboprophylaxis is recommended in this population after delivery—especially cesarean delivery. These patients also need close monitoring in the post-partum period when they are at increased risk for several complications.

Inadvertent neuraxial block placement at or above the L1-L2 interspace in the super-obese parturient: a retrospective study

BACKGROUND

Increasing body mass index (BMI) increases the difficulty of neuraxial procedures. We hypothesized that it may put patients at risk for inappropriately high dural puncture. The accuracy of anesthesiologists' estimates of the interspinous level in super-obese parturients has not been studied. We evaluated the frequency of inadvertently high epidural and/or intrathecal catheter placement (at or above the L1/L2 interspace) in parturients of BMI ≥50 kg/m².

METHODS

Inclusion criteria for this retrospective study were women with a BMI ≥50 kg/m² who delivered by cesarean with an epidural or intrathecal catheter. The primary outcome was the percentage of catheters placed at or above L1/L2, determined by reviewing the retained foreign object radiograph. Secondary outcomes were agreement between the estimated and actual catheter location and subgroup analysis of catheters placed under ultrasound guidance.

RESULTS

After excluding 15 cases for which the catheter location could not be determined and 10 cases for which the estimated level of insertion was not recorded, 125 cases were included. Inadvertent high placement occurred in 26/125 (21%, 95% confidence interval (CI) 15% to 29%) patients. There was poor agreement between the estimated and actual catheter location (27% accurate, unweighted κ-statistic 0.02). Eleven of 39 catheters placed with ultrasound (28%, 95% CI 17% to 44%) were at or above L1/L2 compared with 15/86 catheters placed without ultrasound (17%, 95% CI 11% to 27%, P=0.17). There were no neurological complications.

CONCLUSIONS

A high rate of inadvertently high epidural or intrathecal catheter placement occurs in super-obese parturients. Ultrasound did not prevent this.

Maternal Body Mass Index and Use of Labor Neuraxial Analgesia: A Population-based Retrospective Cohort Study

WHAT WE ALREADY KNOW ABOUT THIS TOPIC

WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: Neuraxial labor analgesia may benefit obese women by optimizing cardiorespiratory function and mitigating complications related to emergency general anesthesia. We hypothesized that obese women have a higher rate of neuraxial analgesia compared with nonobese parturients.

METHODS

Using U.S. natality data, our cohort comprised 17,220,680 deliveries, which accounts for 61.5% of 28 million births in the United States between 2009 and 2015. We examined the relationships between body mass index class and neuraxial labor analgesia, adjusting for sociodemographic, antenatal, pregnancy, and peripartum factors.

RESULTS

The study cohort comprised 17,220,680 women; 0.1% were underweight, 12.7% were normal body mass index, 37% were overweight, and 28.3%, 13.5%, and 8.4% were obesity class I, II, and III, respectively. Rates of neuraxial analgesia by body mass index class were as follows: underweight, 59.7% (9,030/15,128); normal body mass index, 68.1% (1,487,117/2,182,797); overweight, 70.3% (4,476,685/6,368,656); obesity class I, 71.8% (3,503,321/4,881,938); obesity class II, 73.4% (1,710,099/2,330,028); and obesity class III, 75.6% (1,089,668/1,442,133). Compared to women with normal body mass index, the likelihood of receiving neuraxial analgesia was slightly increased for overweight women (adjusted relative risk, 1.02; 95% CI, 1.02 to 1.02), obese class I (adjusted relative risk, 1.04; 95% CI, 1.04 to 1.04), obese class II (adjusted relative risk, 1.05; 95% CI, 1.05 to 1.05), and obese class III (adjusted relative risk, 1.06; 95% CI, 1.06 to 1.06).

CONCLUSIONS

Our findings suggest that the likelihood of receiving neuraxial analgesia is only marginally increased for morbidly obese women compared to women with normal body mass index.

Anesthetic and obstetric outcomes in pregnant women undergoing cesarean delivery according to body mass index: Retrospective analysis of a single-center experience

Aim

To evaluate maternal, neonatal and anesthetic outcomes according to BMI in women undergoing cesarean section.

Background

Increased incidence rates of obesity and morbid obesity have been reported in the United States. Pregnant obese patients are at increased risk of maternal and fetal complications, and obstetric and anesthetic management of these patients is especially challenging.

Methods

A retrospective chart review of patients who underwent cesarean section in a single center between 2015 and 2016 was conducted. Anesthetic, obstetric and neonatal outcomes were analyzed in relation to levels of BMI.

Results

Seven hundred and seventy one patients underwent cesarean section during the study period. The number of patients with normal BMI, obesity and morbid obesity was 213 (27.6%), 365 (47.3%) and 193 (25%), respectively. Sixty-one percent of the patients in morbidly obese group had at least one comorbidity (p < 0.01). We found no significant differences with respect to perioperative obstetric complications. Intraoperative blood loss was significantly higher in the morbidly obese group.

Conclusion

Increasing BMI is associated with comorbidities such as hypertension and diabetes mellitus, and with increased intraoperative blood loss. We were unable to detect differences in other obstetric, anesthetic and neonatal outcomes.

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Incidence of morbid obesity is high in pregnancy.

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Morbid obesity is associated with medical and obstetric morbidities.

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Body mass index is associated with hypertension and diabetes mellitus in pregnant patients.

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Increased blood loss in cesarean section is associated with high body mass index.

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No significant maternal or anesthetic complications can be attributed solely to increasing body mass index.

Double Assurance of Epidural Space Detection Using Fiberoptics-Based Needle Design and Autofluorescence Technologies for Epidural Blockade in Painless Labor

Purpose: Technology of reflectance spectroscopy incorporated with auto-fluorescence spectroscopy were employed to increase the safety of epidural placement in regional anesthesia which is generally used for surgery, epidural anesthesia, post-operative pain control and painless childbirth. Method: Ex vivo study of auto-fluorescence spectroscopy was performed for the para-vertebral tissues contained fat, interspinous ligament, supraspinous ligament and ligamentumflavum by multimode microplate reader at wavelength 405 nm for the purpose of tissue differentiation. A specially designed optic-fiber-embedded needle was employed to incorporate with both reflectance and autofluorescence spectroscopies in order to probe the epidural space as double assurance demands. In vivo study was carried out in a Chinese native swine weighted about 30 kg under intubated general anesthesia with ventilation support. The reflective (405 nm) and autofluorescence signals (λ and λ*) were recorded at 5 different sites by an oscilloscope during the needle puncture procedure from skin to epidural space in the back of the swine. Results: Study of either autofluorescence spectroscopy for tissue samples or ex vivo needle puncture in porcine trunk tissues indicates that ligmentumflavum has at least 10-fold higher fluorescence intensity than the other tissues. In the in vivo study, ligamentumflavum shows a double-peak character for both reflectance and autofluorescence signals. The epidural space is located right after the drop from the double-peak. Both peaks of reflectance and fluorescence are coincident which ensures that the epidural space is correctly detected. Conclusions: The fiber-optical technologies of double-assurance demands for tissue discrimination during epidural needle puncture can not only provide an objective visual information in a real-time fashion but also it can help the operator to achieve much higher success rate in this anesthesia procedure.

Pregnancy in Women with Obesity

Pregnancy in women with obesity is an important public health problem with short- and long-term implications for maternal and child health. Obesity complicates almost all aspects of pregnancy. Given the growing prevalence of obesity in women, obstetric providers need to understand the risks associated with obesity in pregnancy and the unique aspects of management for women with obesity. Empathic and patient-centered care, along with knowledge, can optimize outcomes for women and children.

Epidural extension failure in obese women is comparable to that of non-obese women

BACKGROUND

Management of labor epidurals in obese women is difficult and extension to surgical anesthesia is not always successful. Our previous retrospective pilot study found epidural extension was more likely to fail in obese women. This study used a prospective cohort to compare the failure rate of epidural extension in obese and non-obese women and to identify risk factors for extension failure.

METHODS

One hundred obese participants (Group O, body mass index ≥ 40 kg/m² ) were prospectively identified and allocated two sequential controls (Group C, body mass index ≤ 30 kg/m² ). All subjects utilized epidural labor analgesia and subsequently required anesthesia for cesarean section. The primary outcome measure was failure of the labor epidural to be used as the primary anesthetic technique. Risk factors for extension failure were identified using Chi-squared and logistic regression.

RESULTS

The odds ratio (OR) of extension failure was 1.69 in Group O (20% vs. 13%; 95% CI: 0.88-3.21, P = 0.11). Risk factors for failure in obese women included ineffective labor analgesia requiring anesthesiologist intervention, (OR 3.94, 95% CI: 1.16-13.45, P = 0.028) and BMI > 50 kg/m² (OR 3.42, 95% CI: 1.07-10.96, P = 0.038).

CONCLUSION

The failure rate of epidural extension did not differ significantly between the groups. Further research is needed to determine the influence of body mass index > 50 kg/m² on epidural extension for cesarean section.

Peripartum Management of Obstructive Sleep Apnea

The prevalence of obstructive sleep apnea is unknown during pregnancy, but the syndrome is likely underdiagnosed and rising in frequency along with the obesity epidemic. Obstructive sleep apnea is associated with adverse outcomes, including hypertensive disorders of pregnancy, gestational diabetes, preterm, and cesarean delivery. Obese pregnant women should be screened and referred to a sleep medicine specialist for evaluation. Continuous positive airway pressure is the treatment of choice with demonstrated safety and compliance in pregnancy. Early anesthesia consultation allows for preparation and implementation of a peripartum plan that includes early labor analgesia, avoidance of respiratory depressants, and closer monitoring of oxygenation.

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.

Maternal Body Mass Index and Regional Anaesthesia Use at Term: Prevalence and Complications

BACKGROUND

There is an evidence gap regarding the use of regional anaesthesia (epidural, spinal, or combined epidural/spinal anaesthesia) and associated complications by maternal body mass index (BMI). We examine associations between regional anaesthesia, mode of delivery, and regional anaesthesia complications by pre-pregnancy BMI categories among term deliveries.

METHODS

Retrospective cohort study of births in California, 2007-2010, utilizing linked birth certificate data and patient discharge data. Outcomes were mode of delivery (among laboured deliveries) and select regional anaesthesia complications. Multivariable Poisson regression was used to adjust for maternal characteristics.

RESULTS

In women undergoing labour (i.e. laboured delivery), women with higher BMI categories were more likely to receive regional analgesia in a dose-response fashion (adjusted risk ratio [RR] 1.10, 95% confidence interval [CI] 1.10, 1.11 for primiparous women with category I obesity), and in those receiving regional anaesthesia, were less likely to deliver vaginally (e.g. RR 0.85, 95% CI 0.84, 0.85 for the same category of women). Regional anaesthesia complications displayed a complex relationship with maternal BMI, with women in intermediate obesity categories having decreased odds as compared to normal-weight women, and women in the highest BMI category having a twofold increased risk of complications (RR 2.34, 95% CI 1.37, 4.02 for primiparous women).

CONCLUSION

Labouring women in higher BMI categories were more likely to receive regional anaesthesia and more likely to deliver via caesarean compared to normal weight women and women without regional anaesthesia. Rates of anaesthesia complications were highest among women in the highest BMI category.

Continuous Spinal Anesthesia for Obstetric Anesthesia and Analgesia

The widespread use of continuous spinal anesthesia (CSA) in obstetrics has been slow because of the high risk for post-dural puncture headache (PDPH) associated with epidural needles and catheters. New advances in equipment and technique have not significantly overcome this disadvantage. However, CSA offers an alternative to epidural anesthesia in morbidly obese women, women with severe cardiac disease, and patients with prior spinal surgery. It should be strongly considered in parturients who receive an accidental dural puncture with a large bore needle, on the basis of recent work suggesting significant reduction in PDPH when intrathecal catheters are used. Small doses of drug can be administered and extension of labor analgesia for emergency cesarean delivery may occur more rapidly compared to continuous epidural techniques.

Anaesthetists' experiences with the early labour epidural recommendation for obese parturients: a qualitative study

Caring for obese pregnant women presents challenges for all medical professionals. Despite a lack of supporting evidence, expert opinion and international guidelines suggest early labour epidural insertion for obese women. Anecdotally this is not supported by all anaesthetists. This qualitative study explored the experiences of anaesthetists regarding early epidural analgesia in obese parturients, to answer the research question: Are anaesthetists consistent in how they apply early epidural analgesia in obese parturients? Personal in-depth interviews with 42 specialist anaesthetists working in south-east Queensland, Australia, were completed between February and April, 2015. Leximancer™ text analysis software applied a validated algorithm to the data to identify themes and concepts. The major themes were explored by the first author to answer the research question. Three major themes were identified: the demands associated with caring for obese women; concern regarding the anaesthetic technique used in obese women; and the importance of communication with obstetric staff. Disagreement regarding interpretation and application of early epidural analgesia was identified within this group of anaesthetists. These anaesthetists were inconsistent in how they interpreted and applied early epidural analgesia for obese parturients, with some questioning the validity of the practice. The combination of uncertainty, urgency and technical difficulty presented by obese parturients provoked anxiety in these clinicians, particularly the anticipation of unplanned general anaesthesia. Consistent anaesthetic practice could improve the implementation of early epidural analgesia in obese parturients.

Raman Spectroscopy Differentiates Each Tissue from the Skin to the Spinal Cord: A Novel Method for Epidural Needle Placement?

BACKGROUND

Neuraxial anesthesia and epidural steroid injection techniques require precise anatomical targeting to ensure successful and safe analgesia. Previous studies suggest that only some of the tissues encountered during these procedures can be identified by spectroscopic methods, and no previous study has investigated the use of Raman, diffuse reflectance, and fluorescence spectroscopies. The authors hypothesized that real-time needle-tip spectroscopy may aid epidural needle placement and tested the ability of spectroscopy to distinguish each of the tissues in the path of neuraxial needles.

METHODS

For comparison of detection methods, the spectra of individual, dissected ex vivo paravertebral and neuraxial porcine tissues were collected using Raman spectroscopy (RS), diffuse reflectance spectroscopy, and fluorescence spectroscopy. Real-time spectral guidance was tested using a 2-mm inner-diameter fiber-optic probe-in-needle device. Raman spectra were collected during the needle's passage through intact paravertebral and neuraxial porcine tissue and analyzed afterward. The RS tissue signatures were verified as mapping to individual tissue layers using histochemical staining and widefield microscopy.

RESULTS

RS revealed a unique spectrum for all ex vivo paravertebral and neuraxial tissue layers; diffuse reflectance spectroscopy and fluorescence spectroscopy were not distinct for all tissues. Moreover, when accounting for the expected order of tissues, real-time Raman spectra recorded during needle insertion also permitted identification of each paravertebral and neuraxial porcine tissue.

CONCLUSIONS

This study demonstrates that RS can distinguish the tissues encountered during epidural needle insertion. This technology may prove useful during needle placement by providing evidence of its anatomical localization.

Obstetric analgesia - update 2016

Neuraxial labor analgesia can be initiated via combined spinal-epidural (CSE) or stand-alone epidural. Pros and cons of these techniques are outlined in this review. In recent years computer-integrated patient-controlled epidural analgesia (CI-PCEA) and programed intermittent epidural boluses (PIEB) have been developed, adding to continuous infusion and PCEA for the maintenance of neuraxial analgesia. Postdural puncture headache (PDPH) and fever can occur secondary to labor epidural that both have clinical relevance for the care givers. Insights into the mechanism of epidural fever and treatment strategies for PDPH are outlined. Due to the increase in obesity the specific considerations for this patient group are discussed. New data have been presented for remifentanil, an ultra-shortly acting opioid, that is used in obstetric analgesia. Without breaking new data, the use of nitrous oxide especially by midwives has a kind of renaissance, and this will be discussed, too.

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.

Anaesthetic Management of Obese Parturients: What is the Evidence Supporting Practice Guidelines?

Increasing rates of obesity in western populations present management difficulties for clinicians caring for obese pregnant women. Various governing bodies have published clinical guidelines for the care of obese parturients. These guidelines refer to two components of anaesthetic care: anaesthetic consultation in the antenatal period for women with a body mass index (BMI) > 40 kg/m2 and the provision of early epidural analgesia in labour. These recommendations are based on the increased incidence of obstetric complications and the predicted risks and difficulties in providing anaesthetic care. The concept behind early epidural analgesia is logical—site the epidural early, use it for surgical anaesthesia and avoid general anaesthesia if surgery is required. Experts support this recommendation, but there is weak supporting evidence. It is known that the management of labour epidurals in obese women is complicated and that women with extreme obesity require higher rates of general anaesthesia. Anecdotally, anaesthetists view and apply the early epidural recommendation inconsistently and the acceptability of early epidural analgesia to pregnant women is variable. In this topic review, we critically appraise these two practice recommendations. The elements required for effective implementation in multidisciplinary maternity care are considered. We identify gaps in the current literature and suggest areas for future research. While prospective cohort studies addressing epidural extension (‘top-up’) in obese parturients would help inform practice, audit of local practice may better answer the question “is early epidural analgesia beneficial to obese women in my practice?”.

Managing anesthesia for cesarean section in obese patients: current perspectives

Obesity is a worldwide epidemic. It is associated with increased comorbidities and increased maternal, fetal, and neonatal complications. The risk of cesarean delivery is also increased in obese parturients. Anesthetic management of the obese parturient is challenging and requires adequate planning. Therefore, those patients should be referred to antenatal anesthetic consultation. Anesthesia-related complications and maternal mortality are increased in this patient population. The risk of difficult intubation is increased in obese patients. Neuraxial techniques are the preferred anesthetic techniques for cesarean delivery in obese parturients but can be technically challenging. An existing labor epidural catheter can be topped up for cesarean delivery. In patients who do not have a well-functioning labor epidural, a combined spinal epidural technique might be preferred over a single-shot spinal technique since it is technically easier in obese parturients and allows for extending the duration of the block as required. A continuous spinal technique can also be considered. Studies suggest that there is no need to reduce the dose of spinal bupivacaine in the obese parturient, but there is little data about spinal dosing in super obese parturients. Intraoperatively, patients should be placed in a ramped position, with close monitoring of ventilation and hemodynamic status. Adequate postoperative analgesia is crucial to allow for early mobilization. This can be achieved using a multimodal regimen incorporating neuraxial morphine (with appropriate observations) with scheduled nonsteroidal anti-inflammatory drugs and acetaminophen. Thromboprophylaxis is also important in this patient population due to the increased risk of thromboembolic complications. These patients should be monitored carefully in the postoperative period, since there is increased risk of postoperative complications in the morbidly obese parturients.

Obstetric Anaesthetists' Association and Difficult Airway Society guidelines for the management of difficult and failed tracheal intubation in obstetrics

The Obstetric Anaesthetists' Association and Difficult Airway Society have developed the first national obstetric guidelines for the safe management of difficult and failed tracheal intubation during general anaesthesia. They comprise four algorithms and two tables. A master algorithm provides an overview. Algorithm 1 gives a framework on how to optimise a safe general anaesthetic technique in the obstetric patient, and emphasises: planning and multidisciplinary communication; how to prevent the rapid oxygen desaturation seen in pregnant women by advocating nasal oxygenation and mask ventilation immediately after induction; limiting intubation attempts to two; and consideration of early release of cricoid pressure if difficulties are encountered. Algorithm 2 summarises the management after declaring failed tracheal intubation with clear decision points, and encourages early insertion of a (preferably second-generation) supraglottic airway device if appropriate. Algorithm 3 covers the management of the 'can't intubate, can't oxygenate' situation and emergency front-of-neck airway access, including the necessity for timely perimortem caesarean section if maternal oxygenation cannot be achieved. Table 1 gives a structure for assessing the individual factors relevant in the decision to awaken or proceed should intubation fail, which include: urgency related to maternal or fetal factors; seniority of the anaesthetist; obesity of the patient; surgical complexity; aspiration risk; potential difficulty with provision of alternative anaesthesia; and post-induction airway device and airway patency. This decision should be considered by the team in advance of performing a general anaesthetic to make a provisional plan should failed intubation occur. The table is also intended to be used as a teaching tool to facilitate discussion and learning regarding the complex nature of decision-making when faced with a failed intubation. Table 2 gives practical considerations of how to awaken or proceed with surgery. The background paper covers recommendations on drugs, new equipment, teaching and training.

Patient-centered Care in Maternity Services: A Critical Appraisal and Synthesis of the Literature

BACKGROUND

Patient-centered care (PCC) has been recognized as a marker of quality in health service delivery. In policy documents, PCC is often used interchangeably with other models of care. There is a wide literature about PCC, but there is a lack of evidence about which model is the most appropriate for maternity services specifically.

AIM

We sought to identify and critically appraise the literature to identify which definition of PCC is most relevant for maternity services.

METHODS

The four-step approach used to identify definitions of PCC was to 1) search electronic databases using key terms (1995-2011), 2) cross-reference key papers, 3) search of specific journals, and 4) search the grey literature. Four papers and two books met our inclusion criteria.

ANALYSIS

A four-criteria critical appraisal tool developed for the review was used to appraise the papers and books.

MAIN RESULTS

From the six identified definitions, the Shaller's definition met the majority of the four criteria outlined and seems to be the most relevant to maternity services because it includes physiologic conditions as well as pathology, psychological aspects, a nonmedical approach to care, the greater involvement of family and friends, and strategies to implement PCC.

CONCLUSION

This review highlights Shaller's definitions of PCC as the one that would be the most inclusive of all women using maternity services. Future research should concentrate on evaluating programs that support PCC in maternity services, and testing/validating this model of care.

Complications of 761 short-term intrathecal macrocatheters in obstetric patients: a retrospective review of cases over a 12-year period

BACKGROUND

A continuous spinal catheter is a reliable alternative to standard neuraxial techniques in obstetric anesthesia. Despite the potential advantages of intrathecal catheters, they remain underutilized due to fear of infection, nerve damage or post-dural puncture headache. In our tertiary care center, intrathecal catheters are either placed intentionally in high-risk obstetric patients or following inadvertent dural puncture using a 19-gauge macrocatheter passed through a 17-gauge epidural needle.

METHODS

A retrospective review of 761 intrathecal catheters placed from 2001 to 2012 was conducted. An institutional obstetric anesthesia database was used to identify patients with intrathecal catheters. Medical records were reviewed for procedural details and complications.

RESULTS

There were no serious complications, including meningitis, epidural or spinal abscess, hematoma, arachnoiditis, or cauda equina syndrome, associated with intrathecal catheters. The failure rates were 2.8% (3/108) for intentional placements and 6.1% (40/653) for placements following accidental dural puncture. The incidence of post-dural puncture headache was 41% (312/761) and the epidural blood patch rate was 31% (97/312).

CONCLUSIONS

This review demonstrates that intrathecal catheters are dependable and an option for labor analgesia and surgical anesthesia for cesarean delivery. Serious long-lasting complications are rare.

Video laryngoscopes and the obstetric airway

The pitfalls surrounding securing the airway in the obstetric patient are well documented. From Tunstall's original failed intubation drill onwards, there has been progress both in recognition of the difficulties of airway management in the pregnant patient and development of algorithms to enhance patient safety. Current trends in obstetric anaesthesia have resulted in a significant decrease in exposure of anaesthetists, especially trainees, to caesarean section under general anaesthesia, compounding the difficulties in safely managing the airway. Video laryngoscopes have recently appeared in airway algorithms. They improve glottic visualisation and are useful in the management of the difficult non-obstetric airway, including those in morbidly obese patients and in the setting of a rapid-sequence induction. There is growing interest in the potential use of video laryngoscopes in the obstetric population and as a teaching tool to maximise training opportunities.