Prevalence of difficult intubation and failed intubation in a diverse obstetric community-based population

Trauma in Pregnancy

Trauma is the leading cause of nonobstetric maternal death. Pregnant patients have a similar spectrum of traumatic injuries with a noted increase in interpersonal violence. A structured approach to trauma evaluation and management is recommended with several guidelines expanding on ATLS principles; however, evidence is limited. Optimal management requires understanding of physiologic changes in pregnancy, a team-based approach, and preparation for interventions that may including neonatal resuscitation. The principles of trauma management are the same in pregnancy with a systematic approach and initial maternal focused resuscitation..

Frequency and Risk Factors for Difficult Intubation in Women Undergoing General Anesthesia for Cesarean Delivery: A Multicenter Retrospective Cohort Analysis

BACKGROUND

Estimates for the incidence of difficult intubation in the obstetric population vary widely, though prior studies reporting rates of difficult intubation in obstetrics are older and limited by smaller samples. The goals of this study were to provide a contemporary estimate of the frequency of difficult and failed intubation in women undergoing general anesthesia for cesarean delivery and to elucidate risk factors for difficult intubation in women undergoing general anesthesia for cesarean delivery.

METHODS

This is a multicenter, retrospective cohort study utilizing the Multicenter Perioperative Outcomes Group database. The study population included women aged 15-44 undergoing general anesthesia for cesarean delivery between 2004 and 2019 at one of 45 medical centers. Co-primary outcomes included the frequencies of difficult and failed intubation. Difficult intubation was defined as Cormack-Lehane view ≥3, intubation attempts ≥3, rescue fiberoptic intubation, rescue supraglottic airway, or surgical airway. Failed intubation was defined as any attempt at intubation without successful endotracheal tube placement. Rates of difficult and failed intubation were assessed. Several patient demographic, anatomical, and obstetric factors were evaluated for potential associations with difficult intubation.

RESULTS

We identified 14,748 cases of cesarean delivery performed under general anesthesia. There were 295 cases of difficult intubation, with a frequency of 1:49 (95% CI: 1:55, 1:44) (n=14,531). There were 18 cases of failed intubation, with a frequency of 1:808 (95% CI: 1:1,276, 1:511) (n=14,537). Factors with the highest point estimates for the odds of difficult intubation included increased body mass index, Mallampati score III or IV, small hyoid to mentum distance, limited jaw protrusion, limited mouth opening, and cervical spine limitations.

CONCLUSIONS

In this large, multi-center, contemporary study of over 14,000 general anesthetics for cesarean delivery, we observed an overall risk of difficult intubation of 1:49 and a risk of failed intubation of 1:808. Most risk factors for difficult intubation were non-obstetric in nature. These data demonstrate that difficult intubation in obstetrics remains an ongoing concern.

Canadian Airway Focus Group updated consensus-based recommendations for management of the difficult airway: part 1. Difficult airway management encountered in an unconscious patient

PURPOSE

Since the last Canadian Airway Focus Group (CAFG) guidelines were published in 2013, the literature on airway management has expanded substantially. The CAFG therefore re-convened to examine this literature and update practice recommendations. This first of two articles addresses difficulty encountered with airway management in an unconscious patient.

SOURCE

Canadian Airway Focus Group members, including anesthesia, emergency medicine, and critical care physicians, were assigned topics to search. Searches were run in the Medline, EMBASE, Cochrane Central Register of Controlled Trials, and CINAHL databases. Results were presented to the group and discussed during video conferences every two weeks from April 2018 to July 2020. These CAFG recommendations are based on the best available published evidence. Where high-quality evidence was lacking, statements are based on group consensus.

FINDINGS AND KEY RECOMMENDATIONS

Most studies comparing video laryngoscopy (VL) with direct laryngoscopy indicate a higher first attempt and overall success rate with VL, and lower complication rates. Thus, resources allowing, the CAFG now recommends use of VL with appropriately selected blade type to facilitate all tracheal intubations. If a first attempt at tracheal intubation or supraglottic airway (SGA) placement is unsuccessful, further attempts can be made as long as patient ventilation and oxygenation is maintained. Nevertheless, total attempts should be limited (to three or fewer) before declaring failure and pausing to consider "exit strategy" options. For failed intubation, exit strategy options in the still-oxygenated patient include awakening (if feasible), temporizing with an SGA, a single further attempt at tracheal intubation using a different technique, or front-of-neck airway access (FONA). Failure of tracheal intubation, face-mask ventilation, and SGA ventilation together with current or imminent hypoxemia defines a "cannot ventilate, cannot oxygenate" emergency. Neuromuscular blockade should be confirmed or established, and a single final attempt at face-mask ventilation, SGA placement, or tracheal intubation with hyper-angulated blade VL can be made, if it had not already been attempted. If ventilation remains impossible, emergency FONA should occur without delay using a scalpel-bougie-tube technique (in the adult patient). The CAFG recommends all institutions designate an individual as "airway lead" to help institute difficult airway protocols, ensure adequate training and equipment, and help with airway-related quality reviews.

Maternal cardiac arrest

PURPOSE OF REVIEW

The review is intended to serve as a practical clinical aid for the clinician called to maternal cardiac arrest.

RECENT FINDINGS

Anesthesia complications comprise an important cause of maternal cardiac arrest in developed countries Also predominant are hemorrhage and infections. Recent in-depth reports highlight fractionated care for pregnant women with cardiac and also probably neurological comorbidities. Pathology reports reveal a prevalence of thromboembolic phenomena that is higher than previously assumed but still rare. These are accompanied by particularly high mortality rates. The presenting rhythms of cardiac arrest which differ from most cardiac arrest populations, suggest the need for further in-depth investigation of both the causes and management of these cases. Despite these, outcomes are far better than those of most arrests. Key differences in treatment include are consideration of early airway management and possible medication complications. Pulseless electrical activity and VF should always alert to the possibility of hemorrhage. Echocardiography can diagnose thromboembolism. Also different are the need for Left uterine displacement and early delivery within after 4-5 min of initiation of resuscitation effort in cases with suspected compromise of the venous return or a poor likelihood of a good maternal outcome.

SUMMARY

Maternal cardiac arrest should be managed similarly to other adult cardiac arrests. At the same time its unique reversible causes require a different form of thought regarding diagnosis and treatment during the code.