Airway management and training in obstetric anaesthesia

Enhancing knowledge, skills, and comfort in providing anesthesia assistance during obstetric general anesthesia for operating room nurses: a prospective observational study

BACKGROUND

Due to a nationwide shortage of anesthesia assistants, operating room nurses are often recruited to assist with the induction of obstetric general anesthesia (GA). We developed and administered a training program and hypothesized there would be significant improvements in knowledge and skills in anesthesia assistance during obstetric GA by operating room nurses following training with adequate retention at six months.

METHODS

Following informed consent, all operating room nurses at our institution were invited to participate in the study. Baseline knowledge of participants was assessed using a 14-item multiple choice questionnaire (MCQ), and skills were assessed using a 12-item checklist scored by direct observation during simulated induction of GA. Next, a 20-min didactic lecture followed by a ten-minute hands-on skills station were delivered. Knowledge and skills were immediately reassessed after training, and again at six weeks and six months. The primary outcomes of this study were adequate knowledge and skills retention at six months, defined as achieving ≥ 80% in MCQ and ≥ 80% in skills checklist scores and analyzed using longitudinal mixed-effects linear regression.

RESULTS

A total of 34 nurses completed the study at six months. The mean MCQ score at baseline was 8.9 (95% confidence interval [CI], 8.5 to 9.4) out of 14. The mean skills checklist score was 5.5 (95% CI, 4.9 to 6.1) out of 12. The mean comfort scores for assisting elective and emergency Cesarean deliveries were 3.6 (95% CI, 3.2 to 3.9) and 3.1 (95% CI, 2.7 to 3.5) out of 5, respectively. There was a significant difference in the mean MCQ and skills checklist scores across the different study periods (overall P value < 0.001). Post hoc pairwise tests suggested that, compared with baseline, there were significantly higher mean MCQ scores at all time points after the training program at six weeks (11.9; 95% CI, 11.4 to 12.4; P < 0.001) and at six months (12.0; 95% CI, 11.5 to 12.4; P < 0.001).

DISCUSSION

The knowledge and skills of operating room nurses in providing anesthesia assistance during obstetric GA at our institution were low at baseline. Following a single 30-min in-house, anesthesiologist-led, structured training program, scores in both dimensions significantly improved. Although knowledge improvements were adequately retained for up to six months, skills improvements decayed rapidly, suggesting that sessions should be repeated at six-week intervals, at least initially.

The physiologically difficult airway: an emerging concept

PURPOSE OF REVIEW

The physiologically difficult airway is one in which physiologic alterations in the patient increase the risk for cardiorespiratory and other complications during tracheal intubation and transition to positive pressure ventilation. This review will summarize the recent literature around the emerging concept of the physiologically difficult airway, describe its relevance and various patient types in which this entity is observed.

RECENT FINDINGS

Physiologic derangements during airway management occur due acute illness, pre-existing disease, effects of anesthetic agents, and positive pressure ventilation. These derangements are especially recognized in critically ill patients, but can also occur in otherwise healthy patients including obese, pregnant and pediatric patients who have certain physiological alterations. Critically ill patients may have a physiologically difficult airway due to the presence of acute respiratory failure, hypoxemia, hypotension, severe metabolic acidosis, right ventricular failure, intracranial hypertension, and risk of aspiration of gastric contents during tracheal intubation.

SUMMARY

Understanding the physiological alterations and the risks involved in patients with a physiologically difficult airway is necessary to optimize the physiology and adopt strategies to avoid complications during tracheal intubation. Further research will help us better understand the optimal strategies to improve outcomes in these patients.

Analysis of Airway Management for Cesarean Delivery: Use of Risk and Proportion Differences

OBJECTIVES

Securing the parturient airway is essential during general anesthesia for cesarean delivery. The purpose of this study was to compare inferior airway views provided by the use of three commonly available laryngoscopy blades-Macintosh, Miller, or Glidescope Mac-Style-to the incidence of difficult orotracheal intubation.

METHODS

Following institutional review board approval, data from 449 electronic medical records in parturients undergoing general anesthesia for cesarean delivery were extracted during a 6-year period. The association of these blades with difficult orotracheal intubation was analyzed with risk and proportion differences measures of effect size.

RESULTS

The overall incidence of difficult orotracheal intubation was 4.2% (95% confidence interval 2.7 - 6.5%), with 6 failed orotracheal intubations (5 laryngeal mask airways rescues and 1 mask rescue). Clinically important increases in risk differences for difficult orotracheal intubation were observed in parturients with restricted mouth openings, modified Mallampati III and IV views, and reduced thyromental distances. When modified Cormack-Lehane views were grouped into III and IV versus I and II cohorts; proportion differences for difficult orotracheal intubation were dependent upon the type of blade used, with the Miller blade providing the lowest proportion difference.

CONCLUSIONS

Miller blade laryngoscopy provided the lowest proportion difference for difficult orotracheal intubation during general anesthesia for cesarean delivery. Miller blade laryngoscopy provides effective procurement of the parturient airway.

Anesthesia for Nonobstetric Surgery in Pregnancy

Nonobstetric surgery during pregnancy occurs in 1% to 2% of pregnant women. Physiologic changes during pregnancy may have an impact when anesthesia is needed. Anesthetic agents commonly used during pregnancy are not associated with teratogenic effects in clinical doses. Surgery-related risks of miscarriage and prematurity need to be elucidated with well-designed studies. Recommended practices include individualized use of intraoperative fetal monitoring and multidisciplinary planning to address the timing and type of surgery, anesthetic technique, pain management, and thromboprophylaxis. Emergency procedures should be performed immediately and elective surgery should be deferred during pregnancy.

The Current Role of General Anesthesia for Cesarean Delivery

Purpose of the Review

The use of general anesthesia for cesarean delivery has declined in the last decades due to the widespread utilization of neuraxial techniques and the understanding that neuraxial anesthesia can be provided even in urgent circumstances. In fact, the role of general anesthesia for cesarean delivery has been revisited, because despite recent devices facilitating endotracheal intubation and clinical algorithms, guiding anesthesiologists facing challenging scenarios, risks, and complications of general anesthesia at the time of delivery for both mother and neonate(s) remain significant. In this review, we will discuss clinical scenarios and risk factors associated with general anesthesia for cesarean delivery and address reasons why anesthesiologists should apply strategies to minimize its use.

Recent Findings

Unnecessary general anesthesia for cesarean delivery is associated with maternal complications, including serious anesthesia-related complications, surgical site infection, and venous thromboembolic events. Racial and socioeconomic disparities and low-resource settings are major contributing factors in the use of general anesthesia for cesarean delivery, with both maternal and perinatal mortality increasing when general anesthesia is provided. In addition, more significant maternal pain and higher rates of postpartum depression requiring hospitalization are associated with general anesthesia for cesarean delivery.

Summary

Rates of general anesthesia for cesarean delivery have overall decreased, and while general anesthesia no longer is a contributing factor to anesthesia-related maternal deaths, further opportunities to reduce its use should be emphasized. Raising awareness in identifying situations and patients at risk to help avoid unnecessary general anesthesia remains crucial.

[Update on perioperative hypersensitivity reactions: joint document of the Brazilian Society of Anesthesiology (SBA) and Brazilian Association of Allergy and Immunology (ASBAI) - Part I: post-crisis guidelines and treatment]

Experts from the Brazilian Association of Allergy and Immunology (ASBAI) and the Brazilian Society of Anesthesiology (SBA) interested in the issue of perioperative anaphylaxis, and aiming to strengthen the collaboration between the two societies, combined efforts to study the topic and to prepare a joint document to guide specialists in both areas. The purpose of the present series of two articles was to report the most recent evidence based on the collaborative assessment between both societies. This first article will consider the updated definitions, treatment and guidelines after a perioperative crisis. The following article will discuss the major etiologic agents, how to proceed with the investigation, and the appropriate tests.

High-Risk Airway Management in the Emergency Department: Diseases and Approaches, Part II

BACKGROUND

Successful airway management is critical to the practice of emergency medicine. Thus, emergency physicians must be ready to optimize and prepare for airway management in critically ill patients with a wide range of physiologic challenges. Challenges in airway management commonly encountered in the emergency department are discussed using a pearl and pitfall discussion in this second part of a 2-part series.

OBJECTIVE

This narrative review presents an evidence-based approach to airway and patient management during endotracheal intubation in challenging cases commonly encountered in the emergency department.

DISCUSSION

Adverse events during emergent airway management are common with postintubation cardiac arrest, reported in as many as 1 in 25 intubations. Many of these adverse events can be avoided by proper identification and understanding the underlying physiology, preparation, and postintubation management. Those with high-risk features including trauma, elevated intracranial pressure, upper gastrointestinal bleed, cardiac tamponade, aortic stenosis, morbid obesity, and pregnancy must be managed with airway expertise.

CONCLUSIONS

This narrative review discusses the pearls and pitfalls of commonly encountered physiologic high-risk intubations with a focus on the emergency clinician.

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.

A Contemporary Analysis of Medicolegal Issues in Obstetric Anesthesia Between 2005 and 2015

BACKGROUND

Detailed reviews of closed malpractice claims have provided insights into the most common events resulting in litigation and helped improve anesthesia care. In the past 10 years, there have been multiple safety advancements in the practice of obstetric anesthesia. We investigated the relationship among contributing factors, patient injuries, and legal outcome by analyzing a contemporary cohort of closed malpractice claims where obstetric anesthesiology was the principal defendant.

METHODS

The Controlled Risk Insurance Company (CRICO) is the captive medical liability insurer of the Harvard Medical Institutions that, in collaboration with other insurance companies and health care entities, contributes to the Comparative Benchmark System database for research purposes. We reviewed all (N = 106) closed malpractice cases related to obstetric anesthesia between 2005 and 2015 and compared the following classes of injury: maternal death and brain injury, neonatal death and brain injury, maternal nerve injury, and maternal major and minor injury. In addition, settled claims were compared to the cases that did not receive payment. χ, analysis of variance, Student t test, and Kruskal-Wallis tests were used for comparison between the different classes of injury.

RESULTS

The largest number of claims, 54.7%, involved maternal nerve injury; 77.6% of these claims did not receive any indemnity payment. Cases involving maternal death or brain injury comprised 15.1% of all cases and were more likely to receive payment, especially in the high range (P = .02). The most common causes of maternal death or brain injury were high neuraxial blocks, embolic events, and failed intubation. Claims for maternal major and minor injury were least likely to receive payment (P = .02) and were most commonly (34.8%) associated with only emotional injury. Compared to the dropped/denied/dismissed claims, settled claims more frequently involved general anesthesia (P = .03), were associated with delays in care (P = .005), and took longer to resolve (3.2 vs 1.3 years; P < .0001).

CONCLUSIONS

Obstetric anesthesia remains an area of significant malpractice liability. Opportunities for practice improvement in the area of severe maternal injury include timely recognition of high neuraxial block, availability of adequate resuscitative resources, and the use of advanced airway management techniques. Anesthesiologists should avoid delays in maternal care, establish clear communication, and follow their institutional policy regarding neonatal resuscitation. Prevention of maternal neurological injury should be directed toward performing neuraxial techniques at the lowest lumbar spine level possible and prevention/recognition of retained neuraxial devices.

Recent advances of simulation in obstetric anesthesia

PURPOSE OF REVIEW

Simulation training in obstetric anesthesia has become widespread in recent years. Simulations are used to train staff and trainees, assess and improve team performance, and evaluate the work environment. This review summarizes current research in these categories.

RECENT FINDINGS

Simulation to improve individual technical skills has focused on induction of general anesthesia for emergent cesarean delivery, an infrequently encountered scenario by anesthesia trainees. Low- and high-fidelity simulation devices for the learning and practicing neuraxial and non-neuraxial procedures have been described, and both are equally effective. The use of checklists in obstetric emergencies has become common as and post-scenario debriefing techniques have improved. Although participant task performance improves, whether participants retain learned skills or whether simulation improves patient outcomes has not yet been established. Tools to assess teamwork during simulation have been developed, but none have been rigorously validated. In-situ vs. offsite simulations do not differ in effectiveness.

SUMMARY

Simulation allows for practice of tasks and teamwork in a controlled manner. There is little data whether simulation improves patient outcomes and metrics to predict the long-term retention of skills by simulation participants have not been developed.