Airway changes following labor and delivery in preeclamptic parturients: a prospective case control study

Assessment of airway parameters in obstetric patients and comparing them at different phases in the perinatal period: A prospective observational study

Background and Aims

Airway changes occur in different stages of pregnancy. We aimed to evaluate the changes in the upper airway in obstetric patients during pregnancy, labour and after delivery using multiple airway indices and identify the predictive factors of these changes.

Methods

This observational study was conducted on 90 parturients aged >20 years, having monofoetal pregnancy. The patient's weight was noted, airway assessment including Mallampati grading (MPG), and thyromental distance (TMD), sternomental distance (SMD), neck circumference (NC) and Wilson's risk score were measured in the second trimester of pregnancy (T0), between 32 and 34 weeks of gestation (T1), at the time of admission for safe confinement, between 38 and 40 weeks of gestation (T2), 2 h after delivery of baby (T3) and, 24 h after delivery (T4). Unpaired t-test and analysis of variance test were applied.

Results

Changes in mean (standard deviation [SD]) weight, recorded from T0 to T2, were from 56.96 (10.77) to 65.322 (11.49) kg (P = 0.001). A rise of one or two grades in MPG was detected as the pregnancy progressed, and a decrease of one grade was noted after delivery. A significant decrease in mean (SD) TMD was noted from 6.88 (0.65) to 6.36 (0.62) cm from T0 to T2 (P = 0.001). SMD also decreased in a similar manner as TMD. NC increased from T0 to T3 and then decreased at T4 (P = 0.004).

Conclusion

Following the second trimester of pregnancy, MPG increased by either one or two grades, with a decrease in TMD and SMD and an increase in NC.

The need for maternal critical care education, point-of-care ultrasound and critical care echocardiography in obstetric anesthesiologists training

Globally, the increase in medically complex obstetric patients is challenging the educational approach and clinical management of critically ill obstetric patients. This increase in medical complexity calls into question the educational paradigm in which future physicians are trained. Obstetric anesthesiologists, physician experts in the perio-perative planning and management of complex obstetric patients, represent an essential workforce in the strategies to address maternal mortality. Unfortunately, the development of peri-operative medicine and maternal critical care curricula has only received minor attention in most countries. Proposed guidelines and models highlight the existing need for tiered maternity care services in which critical care infrastructure plays a central role in the delivery of high-risk peripartum care. Therefore, the development of maternal critical care models designed to prepare obstetric anesthesiologists for the clinical challenges of a medically complex patient are warranted. Key critical care topics such as advanced ultrasonography, with the inclusion of quantitative echocardiographic assessments into obstetric anesthesiology educational curricula, will serve to better prepare physicians for the realities of an increasingly complex pregnant patient population, and further reinforce the critical care infrastructure detailed in the Levels of Maternal Care consensus. Despite an increasingly complex obstetric patient population, heterogeneity of maternal critical care practices exists across the globe, warranting standardization and further development of proposed curricula.

Clinical and ultrasonographic assessment of airway indices among non-pregnant, normotensive pregnant and pre-eclamptic patients: a prospective observational study

BACKGROUND

Prediction of a difficult airway is of paramount importance for an anaesthesiologist. Various anatomical and physiological factors contribute to a difficult airway in pregnant females, especially those with pre-eclampsia. The aim of the study was to assess airway indices using both routinely used clinical methods and ultrasound.

METHODS

Fifty-five non-pregnant females, 55 normotensive pregnant females and 55 females with pre-eclampsia were included in this prospective study. Clinical airway assessment was the modified Mallampati score, thyromental distance, hyomental distance, hyomental distance ratio, chest circumference, neck circumference and chest-to-neck circumference ratio. Sonographic assessment included tongue width, tongue volume, anterior neck soft tissue thickness at the level of hyoid, epiglottis and vocal cords, subglottic diameter, ratio of pre-epiglottic space to anterior, posterior and midpoint of anterior and posterior vocal folds.

RESULTS

Several significant differences were observed between pregnant and non-pregnant females, with additional changes in pre-eclamptic females. These included clinical parameters such as the modified Mallampati score and sonographic measurements of tongue width, tongue volume, subglottic diameter, anterior neck soft tissue thickness at the level of hyoid, epiglottis and vocal cords, and the ratio of pre-epiglottic space to anterior, posterior and midpoint of anterior and posterior vocal folds.

CONCLUSION

Routinely used clinical methods of airway assessment lack sensitivity and specificity. Ultrasound can visualise anatomical structures in the supraglottic and subglottic views and is encouraging as an airway assessment tool.

Evaluation of changes in Mallampati class in patients undergoing lumbar spine surgeries in the prone position: A prospective observational study

Background

Positioning of patients during surgery, whether prone or head down, can lead to airway edema which, in turn, may lead to a difficult airway, and enhanced chances for reintubation. We aimed to assess and evaluate modified Mallampati class (MMC) change in patients scheduled for lumbar spine surgery in the prone position.

Materials and Methods

This prospective observational study included 80 patients scheduled for lumbar spine surgery. The MMC was assessed up to 48 h postoperatively. The time taken by the patients in the postoperative period for MMC class to revert to preoperative value and airway complications, if any, was noted. Other parameters observed were surgical duration, intraoperative fluids used, and blood loss to look for any significant correlation with changes in MMC.

Results

MMC increase by one grade was observed in 73 patients (91%). MMC in 54 patients (74%) returned to baseline within 18 h, in 12 patients (16%) it took 24 h, and in the remaining 7 patients (10%) the time taken was 36 h.

Conclusion

It was concluded and established by this study that the MMC declined by one grade and reverted to baseline value within 36 h. This change in MMC necessitates extra caution to be adopted during the postoperative period as surgery in a prone position may predispose to an increased risk of encountering difficult reintubation. The change in MMC was not significantly correlated to intraoperative variables like duration of surgery, amount of intraoperative fluid given, and blood loss.

Haemolysis, elevated liver enzymes and low platelets: Diagnosis and management in critical care

A thirty-year-old pregnant woman was admitted to hospital with headache and gastrointestinal discomfort. She developed peripheral oedema and had an emergency caesarean section following an episode of tonic-clonic seizures. Her delivery was further complicated by postpartum haemorrhage and she was admitted to the Intensive Care Unit (ICU) for further resuscitation and seizure control which required infusions of magnesium and multiple anticonvulsants. Despite haemodynamic optimisation she developed an acute kidney injury with evidence of liver damage, thrombocytopenia and haemolysis. Haemolysis, Elevated Liver enzymes and Low Platelets (HELLP) syndrome, a multisystem disease of advanced pregnancy which overlaps with pre-eclampsia, was diagnosed. HELLP syndrome is associated with a range of complications which may require critical care support, including placental abruption and foetal loss, acute kidney injury, microangiopathic haemolytic anaemia, acute liver failure and liver capsule rupture. Definitive treatment of HELLP is delivery of the fetus and in its most severe forms requires admission to the ICU for multiorgan support. Therapeutic strategies in ICU are mainly supportive and include blood pressure control, meticulous fluid balance and possibly escalation to renal replacement therapy, mechanical ventilation, neuroprotection, seizure control, and management of liver failure-related complications. Multidisciplinary input is essential for optimal treatment.

Idiopathic Subglottic Stenosis during Pregnancy: A Support Group Survey

OBJECTIVES

(1) To determine how pregnancy affects idiopathic subglottic stenosis (iSGS) symptoms. (2) To determine treatments utilized (including operating room (OR) and in-office procedures) for iSGS before, during, and after pregnancy.

METHODS

A 24-question survey was distributed to an international iSGS support group to assess the patient experience among individuals who have been pregnant with diagnosis of iSGS. Descriptive statistics and chi² analyses were completed.

RESULTS

A total of 413 iSGS patients participated; 84.7% (n = 350) of patients were diagnosed prior to menopause. A total of 25.5% patients reported being pregnant when they had airway stenosis; 71.1% of those reported more severe airway symptoms during pregnancy. The proportion of patients that reported requiring ≥1 OR interventions (microlaryngoscopy and bronchoscopy, laser, balloon dilation, or steroid injection) before, during and after pregnancy was the following, respectively: 37.3%, 35.6%, 51.3%. Whereas the proportion of patients that reported requiring ≥1 in-office interventions (awake balloon dilation or steroid injection) before, during and after pregnancy was the following, respectively: 13.6%, 11.8%, 15.8%. Number of pregnancies and age of diagnosis was not related to severity of symptoms or requiring more airway interventions (P > .05).

CONCLUSIONS

This survey reveals worsening of symptoms during pregnancy, however, this did not lead to increase in operative or clinic interventions to improve airway symptoms during pregnancy. Future avenues for research include optimizing management of airway symptoms during pregnancy to limit OR-based interventions.

LEVEL OF EVIDENCE

Level IV.

What's new in obstetric anesthesia in 2018?

The Gerard W. Ostheimer Lecture presented at the annual meeting of the Society of Obstetric Anesthesia and Perinatology (SOAP) is a one-year summary of the literature published in domains of interest to anesthesiologists who manage and care for obstetric patients. One individual is asked to review the literature and present the lecture. This manuscript summarizes aspects of the Gerard W. Ostheimer Lecture presented at the 2019 SOAP meeting; the relevant literature from 2018 was summarized. The topics included in this review are maternal morbidity, antibiotic prophylaxis, anaphylaxis, the Lancet series on increasing cesarean delivery rates, the Robson Ten-Group Classification System, pelvic floor disorders, timing of delivery in nulliparous women, placenta accreta disorders, anesthesia for cesarean delivery, labor analgesia (including parturients with thrombocytopenia and tattoos, and epidural maintenance with the programmed intermittent epidural bolus technique), ultrasound use in obstetric anesthesia, and drugs in pregnancy.

Non-obstetric surgery in pregnancy (including bowel surgery and gallbladder surgery)

Non-obstetric surgery during pregnancy is required in 0.75-2% of pregnancies. Physiologic changes during pregnancy, both hormonal and anatomic, can have interactions with surgery and anesthesia. Indication, timing as well as risks of anesthesia and surgery should be considered in surgical decision making. The health status of the mother should always be put first. A preoperative multidisciplinary approach, also including an obstetrician and neonatologist, is mandatory. Delay in diagnosis and treatment carry risks of complications in all septic visceral indications. Considerations should be individualized.

Evaluation of 2 ultrasonic indicators as predictors of difficult laryngoscopy in pregnant women: A prospective, double blinded study

BACKGROUND

Ultrasonic measurements of tongue thickness and condylar translation were recently introduced to predict difficult laryngoscopy in non-obstetric patients. We designed the present study to evaluate the performance of these two ultrasonic indicators in predicting difficult laryngoscopy in healthy parturients.

METHODS

The 119 parturients undergoing elective cesarean delivery were enrolled. Tongue thickness and condylar translation measured by ultrasonography, and Modified Mallampati test (MMT) score, inter-incisor distance (IID) and modified Cormack-Lehane grading system (MCLS) were measured and recorded before anesthesia. The primary outcome was difficult laryngoscopy defined as MCLS 3 or 4. The association between these variables and difficult laryngoscopy were analyzed by using multivariable logistic regression and receiver operating characteristic (ROC) curve.

RESULTS

Compared to the Easy Laryngoscopy Group, the tongue thickness was significantly higher and the condylar translation and IID were significantly lower in the Difficult Laryngoscopy Group. Tongue thickness and condylar translation but not MMT score and IID were proved to be two independent predictors for difficult laryngoscopy by multivariate logistic regression, with the odds ratios of 2.554 (95% confidence interval (CI), 1.715 to 3.802) and 0.457 (95% CI, 0.304 to 0.686). The area under the ROC curve to predict difficult laryngoscopy for tongue thickness was 0.93 (95% CI, 0.88-0.98) and for condylar translation was 0.77 (95% CI, 0.67-0.86), which were significantly higher than those for MMT score (0.67, 95% CI, 0.56-0.77) and IID (0.65, 95% CI, 0.55-0.76).

CONCLUSIONS

Compared with MMT and IID, tongue thickness and condylar translation measured by ultrasonography appear to be better indicators for predicting difficult laryngoscopy in parturients.The trial was registered at the Chinese Clinical Trial Registry (ChiCTR)(www.chictr.org), registration number ChiCTR-ICR-1800019991.