Unanticipated Consequences of Switching to Sugammadex: Anesthesia Provider Survey on the Hormone Contraceptive Drug Interaction : Anesthesia & Analgesia

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Original Research Articles: Original Clinical Research Report

Unanticipated Consequences of Switching to Sugammadex: Anesthesia Provider Survey on the Hormone Contraceptive Drug Interaction

Dwan, Robyn L. DO; Raymond, Britany L. MD; Richardson, Michael G. MD

Author Information
doi: 10.1213/ANE.0000000000005465



  • Question: What do anesthesiology providers know about the sugammadex-progesterone drug interaction, and how do they manage this interaction clinically in a department utilizing sugammadex as the first-line neuromuscular blocker antagonist?
  • Findings: Attending anesthesiologists, nurse anesthetists, and trainees have incomplete knowledge of potential sugammadex interference with hormonal contraceptives, report little personal involvement in patient counseling, and rarely invite shared decision-making in the choice of antagonist, despite strongly endorsing the latter.
  • Meaning: Targeted education and strengthened policies that encourage patient counseling and support shared decision-making may resolve the observed discrepancy between what providers think they should do and how they actually practice clinically.

Sugammadex binds progesterone with high affinity, which may risk hormonal contraceptive (HC) failure following sugammadex administration.1 Although this complication remains a theoretical risk, absent rigorous pharmacological or clinical evidence to date (no cases reported), the manufacturer of sugammadex recommends alternative, non-HC, such as barrier methods, for 7 days following sugammadex exposure.1 This warning and recommendation have been promulgated by the Society for Obstetric Anesthesia and Perinatology2 and embraced by numerous medical centers.3–8 Some authors have recommended considering intentional avoidance of this interaction by using the alternative neuromuscular blockade (NMB) antagonist, neostigmine.3,4 Ethical considerations of administering sugammadex to women using HC without prior discussion vis-à-vis paternalism have been reviewed,3 but reports describing preoperative discussion with at-risk women of implications of the sugammadex/HC drug interaction are lacking. Instead, most reports describe informing patients of sugammadex exposure and contraceptive counseling ex post facto.5–8

Considering clinical and financial implications of complications from postoperative residual NMB, such as tracheal reintubation, our institution decided that enhanced safety of ensuring complete NMB reversal was worth the added cost of routine sugammadex use instead of neostigmine. Beginning February 2017, sugammadex was officially designated as the NMB antagonist of choice. The policy and rationale were implemented through a grand rounds presentation and department-wide e-mail communications and weekly announcements. Sugammadex was readily available in operating room carts, while the number of neostigmine vials in carts was limited to 1. As reported by other institutions,5–8 women using HC and exposed to sugammadex were to be counseled postoperatively in the postanesthesia care unit (PACU), including provision of an informational document that describes the sugammadex/HC interaction, potential risk of HC failure, and recommendations for alternative contraceptive measures (see Supplemental Digital Content 1, Appendix 1, https://links.lww.com/AA/D413, for discharge instructions for patients exposed to sugammadex).

Based on observations during routine trainee supervision, we hypothesized that trainees and practitioners rarely, if ever, consider the sugammadex–HC interaction in women of childbearing potential, including screening for HC use, preoperative discussion, intraoperative management, and postoperative counseling. We also suspected that designation of sugammadex as antagonist of choice has resulted in trainee knowledge gaps and inexperience with neostigmine. We conducted this survey 2 years after this institutional policy change to determine how anesthesiology providers think this drug interaction should be managed, how they actually manage it clinically, and to assess for knowledge gaps that may have arisen consequent to near-exclusive use of sugammadex in lieu of neostigmine.


The Vanderbilt University Medical Center (VUMC) Institutional Review Board reviewed and approved this study with exempt status; therefore, participant consent was not required. A 35-element survey instrument was constructed with 4 separate sections (see Supplemental Digital Content 2, Appendix 2, https://links.lww.com/AA/D414, for the survey instrument developed for this study). The first section included 3 demographic questions (gender, role, and years of training or years of postgraduate experience). Section 2 queried prior experience antagonizing NMB with neostigmine and sugammadex, knowledge regarding interactions between sugammadex and specific HC, and knowledge of the manufacturer’s counseling recommendations to mitigate potential consequences of that interaction. Section 3 prompted participants to report their prior clinical practices, including screening for at-risk patients, counseling at-risk women regarding the drug interaction, administration of neostigmine to avoid the interaction, and soliciting involvement of patients in shared decision-making regarding choice of NMB antagonist. This section explored participants’ views on whether this drug interaction should be discussed preoperatively, and whether patients should be able to choose or share in the choice of NMB antagonist. Finally, Section 4 simply invited optional additional clarifying comments. Completion of all questions in each section was required to proceed to the next section, and it was not possible to return to a prior completed section.

The 3 investigators developed the survey questions using an iterative Delphi process over several months. Consensus was achieved following several rounds of discussion and revision of questions, section headings, and question order. This included close attention to ensuring alignment between the questions and the hypotheses, sound survey question construction (incorporation of clear, concise, uncomplicated, unambiguous language; avoidance of leading, loaded, and double-barrel questions; minimizing unnecessary redundancy), and ordering of questions in a way that made sense and minimized likelihood of biasing responses. The questions were then loaded into the Research Electronic Data Capture (REDCap) electronic survey and data capture tool hosted at Vanderbilt University.9 The investigators then further revised the survey iteratively, with particular attention to section headings, clarity of instructions, and ease of completion. The draft REDCap survey was pilot tested by 3 post-graduate year (PGY)-5 anesthesiology residents (RES), each serving as regional anesthesiology fellows at separate institutions. After each had completed the survey, an investigator (R.L.D.) obtained feedback from each resident on the questions and on the survey overall. This feedback was used to generate the finalized survey.

From December 2019 to January 2020, the survey was distributed to anesthesiology providers at a large, tertiary academic hospital with 57 operating rooms. Survey data were collected and managed using REDCap. The REDCap survey tool was used to promote survey completion and ensure response anonymity. It delivered e-mail survey participation invitations to 259 providers, comprising 4 groups: attending anesthesiologists (ATTG), RES, certified registered nurse anesthetists (CRNA), and senior student nurse anesthetists (SRNA). Surveys were solicited of all RES trainees, all CRNAs who work with adult patients, all ATTG faculty who provide adult and pediatric anesthesia, and all SRNA trainees who had worked at our medical center during the 4 months before the time of the survey. Inclusion of the latter group provided an opportunity to compare survey results in 2 trainee groups with important similarities and differences. SRNA clinical training is similar to that of residents—they serve as solo, primary in-room anesthesia providers with ATTG supervision. But, unlike resident trainees, SRNAs obtain training at several outside hospitals unaffiliated with our institution. Because their senior clinical year begins in August, potential SRNAs participants were solicited from those who had obtained at least 2 months of recent clinical training experience at our institution. A single automatic reminder notification was sent 7 days following the initial distribution of the survey to those who had not completed a response. Participants were offered a $10 gift card in gratitude for completing the survey.

All data were exported to Microsoft Excel (Microsoft Inc, Redmond, WA, 2010), and results were calculated using Microsoft Excel. Sections Missing data were not included in the final calculations. Data from surveys in which respondents completed only Section 1 (demographic questions) were excluded from analysis. Descriptive statistics were used to analyze and present all responses provided in Sections 2 and 3, with survey answers reported in simple proportions. Reporting is consistent with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines for the reporting of observational research.10


Section 1 (demographic data) was completed by 167 of the 259 providers solicited. Two of the 167 respondents (a male clinical anesthesiologist [CA]2 RES and a first-year female ATTG) completed no further survey questions, so were excluded from the analysis. Section 2 (experience with neostigmine and sugammadex, knowledge of sugammadex–HC interactions and manufacturer’s counseling recommendations) was completed by 165 of the 259 providers solicited, yielding a 64% completion rate overall. This represented completion by 52 of 92 ATTG (57%), 48 of 54 RES (89%), 47 of 79 CRNA (59%), and 18 of 34 SRNA (53%). Eleven respondents dropped out after completing Section 2 (11 of 165, 7%); their completed data are included in the results. Section 3 (screening for and counseling at-risk patients, use of neostigmine to avoid sugammadex–HC interaction, and practices and views of shared decision-making regarding NMB antagonist) was completed by 154 of 259 (59%) overall, which included 44 of 92 surveys solicited from ATTG (48%), 46 of 54 RES (85%), 46 of 79 CRNA (58%), 18 of 34 SRNA (53%). Optional clarifying comments (Section 4) were provided by 21 respondents (12 ATTG, 3 RES, 4 CRNA, 2 SRNA; see Supplemental Digital Content 3, Appendix 3, https://links.lww.com/AA/D415, which details the clarifying comments provided by those 21 survey respondents). Only 18% of respondents requested a gift card.

Table 1. - Characteristics of 4 Groups of Anesthesia Provider Respondents Who Completed Surveys
Role Number (proportion) Female/male
Overall (n = 165) 165 85 (52%)/80 (48%)
 Attending anesthesiologist 52 (32%) 19(37%)/33 (63%)
 Anesthesiology resident 48 (29%) 26(54%)/22 (46%)
  CA1 17
  CA2 17
  CA3 14
 CRNA 47 (28%) 29(62%)/18 (38%)
 SRNA 18 (11%) 11(61%)/7 (39%)
Years of practice since completing training (attending n = 52; CRNA n = 47; total n = 99) Number (proportion)
0–1 8 (8%)
1–5 30 (30%)
6–10 20 (20%)
>10 41 (41%)
Sugammadex available during training? “Yes, routine use” “No,” or “yes, rare use”
Attending anesthesiologist (n = 52) 1 (2%) 51 (98%)
Anesthesiology resident (n = 48) 48 (100%) 0 (0%)
CRNA (n = 47) 7 (15%) 40 (85%)
SRNA (n = 18) 18 (100%) 0 (0%)
Estimated number of times administered neostigmine “≤5” “≥6”
Anesthesiology resident
 CA1 (n = 17) 16 (94%) 1 (6%)
 CA2 (n = 17) 13 (76%) 4 (24%)
 CA3 (n = 14) 8 (57%) 6 (43%)
SRNA (n = 18) 1 (6%) 17 (94%)
Primary NMB antagonist during training? Sugammadex/neostigminea
Attending anesthesiologist (n = 52) 1 (2%)/51 (98%)
Anesthesiology resident (n = 48) 48 (100%)/0 (0%)
CRNA (n = 47) 5 (11%)/42 (89%)
SRNA (n = 18) 14 (78%)/4 (22%)
Certain of correct clinical dose of neostigmine to reverse NMB? Yes/no
Attending anesthesiologist (n = 52) 49 (94%)/3 (6%)
Anesthesiology resident (n = 48) 9 (19%)/39 (81%)
 CA1 2 (12%)/15 (88%)
 CA2 4 (24%)/13 (76%)
 CA3 3 (21%)/11 (79%)
CRNA (n = 47) 43 (91%)/4 (9%)
SRNA (n = 18) 17 (94%)/1 (6%)
Data are presented as number (proportion).
Abbreviations: CA1, clinical anesthesiologist-first year; CA2, clinical anesthesiologist-second year; CA3, clinical anesthesiologist-third year; CRNA, certified registered nurse anesthetist; NMB, neuromuscular blockade; SRNA, student nurse anesthetist.
a“Primary NMB antagonist during training?” was asked only if answer to “Sugammadex available during training?” was “no.” These respondents were assumed to have used neostigmine exclusively during training.

Table 2. - Responses to the Survey Question, “Over the Past Year, How Often Have You Used ___ to Reverse NMB?” Among 4 Groups of Anesthesia Provider Respondents Who Completed Surveys
Almost always (>90%) Occasionally Sometimes (50%) Often Almost never (<10%)
 Attending anesthesiologist (n = 52) 46 (88%) 3 (6%) 2 (4%) 1 (2%) 0 (0%)
 Anesthesiology resident (n = 48) 48 (100%) 0 (0%) 0 (0%) 0 (0%) 0 (0%)
 CRNA (n = 47) 37 (79%) 2 (4%) 1 (2%) 6 (13%) 1 (2%)
 SRNA (n = 18) 2 (11%) 11 (61%) 3 (17%) 2 (11%) 0 (0%)
 Attending anesthesiologist (n = 52) 0 (0%) 0 (0%) 1 (2%) 8 (15%) 43 (83%)
 Anesthesiology resident (n = 48) 0 (0%) 0 (0%) 0 (0%) 3 (6%) 45 (94%)
 CRNA (n = 47) 1 (2%) 1 (2%) 2 (4%) 5 (11%) 38 (81%)
 SRNA (n = 18) 0 (0%) 8 (44%) 7 (39%) 3 (17%) 0 (0%)
Data are presented as number (proportion).
Abbreviations: CRNA, certified registered nurse anesthetist; NMB, neuromuscular blockade; SRNA, student nurse anesthetist.

Survey respondent demographics and their reported clinical experience with NMB antagonists are summarized in Tables 1 and 2, and provide context for interpreting the remainder of the survey. The gender of respondents slightly favored women (85 of 165, 51.5%). The proportional make-up of the 165 participants who completed Section 2 was ATTG 32%, RES 29%, CRNA 28%, and SRNA 11%. Most respondents who had completed training (ie, ATTG and CRNA) reported more than 5 years of experience in their careers (61 of 99, 61%). Only 1 of 52 attendings (2%) and 7 of 47 CRNAs (15%) reported routine use of sugammadex during their training (Table 1), consistent with its relatively recent introduction in the United States following approval by the Food and Drug Administration in 2015. On the other hand, resident respondents, whose training commenced no earlier than summer 2017, reported routine use of sugammadex and very limited experience with neostigmine. The latter was especially true of CA1 and CA2 residents who started training after the departmental switch to sugammadex (Table 1). Reported clinical practice was consistent among ATTG, RES, and CRNA respondents (Table 2), the majority of whom used sugammadex “almost always >90%” to reverse NMB over the past year (96% ATTG, 98% RES, 77% CRNA), which is consistent with the institution’s practice guideline on sugammadex for routine NMB reversal. In contrast, only 2 of 18 (11%) of SRNAs reported using sugammadex “almost always >90%” over the past year. All 18 reported using neostigmine “occasionally,” “sometimes (50%),” or “often” (Table 2).

Clinical Knowledge

Figure 1.:
Proportion of survey respondents among 4 anesthesiology provider groups (RES, SRNA, CRNA, ATTG) that selected each of 5 contraceptives in response to the prompt, “Sugammadex interferes with the efficacy of the following contraceptives (check all that apply):.” ATTG indicates attending anesthesiologists; CRNA, certified registered nurse anesthetists; IUD, intrauterine device; RES, anesthesiology residents; SRNA, student nurse anesthetists.
Figure 2.:
Proportion of respondent answers among 4 anesthesiology provider groups (RES, SRNA, CRNA, ATTG) to the question, “For women on hormonal contraception, how many days should they use barrier protection after receiving sugammadex?” ATTG indicates attending anesthesiologists; CRNA, certified registered nurse anesthetists; RES, anesthesiology residents; SRNA, student nurse anesthetists.

Nearly all ATTG (94%), CRNA (91%), and SRNA (94%) respondents reported being certain of the appropriate clinical dose of neostigmine. In contrast, most resident respondents, 39 of 48 RES (81%), were unsure of the correct dose and conceded they would need to utilize a reference before administering neostigmine to a patient. Participant knowledge regarding the potential for sugammadex interference with different contraceptives is depicted in Figure 1. Nearly all (164 of 165, 99%) participants identified the potential for sugammadex interference with efficacy of oral HC, while most (149 of 165, 90%) knew that sugammadex does not interfere with copper intrauterine device. Knowledge regarding potential interference with other HC was mixed—hormonal intrauterine devices (44%), implants (55% etonogestrel/Nexplanon [Merck & Co, Inc, Whitehouse Station, NJ]), and injections (54% medroxyprogesterone acetate/Depo-Provera [Pfizer, Inc, New York, NY]) (Figure 1). When asked the length of time a patient should be counseled to use barrier protection after sugammadex administration, responses ranged from 2 to 30 days (Figure 2). Most respondents in all 4 groups (72%) correctly reported the manufacturer’s 7-day recommendation, but 22% overall reported 10, 14, or 30 days, and the remaining 6% reported 2–6 days. Most respondents disagreed (36% ATTG, 26% RES, 41% CRNA, 33% SRNA) or strongly disagreed (27% ATTG, 37% RES, 2% CRNA, 22% SRNA) with the statement that potential sugammadex interference with HC is primarily a medicolegal issue rather than a clinically relevant one. Only 25 of 154 (16%) overall responded with agreement or strong agreement, while 46 of 154 (30%) were neutral.

Clinical Practice Versus Ideals

Figure 3.:
Proportion of survey respondents in each of 4 groups (RES, SRNA, CRNA, ATTG) that reported “never” or “rarely (<10%)” to questions about their clinical practices: “With patients taking hormonal contraceptives, how often have you...” ATTG indicates attending anesthesiologists; CRNA, certified registered nurse anesthetists; neostig, neostigmine; RES, anesthesiology residents; SG, sugammadex; SRNA, student nurse anesthetists.
Figure 4.:
Proportion of respondents indicating who (anesthesia provider, patient, or shared decision) may choose between sugammadex and neostigmine, “depending on the circumstances, for women on hormonal contraceptives.” Respondents were instructed to “check all that apply.” ATTG indicates attending anesthesiologists; CRNA, certified registered nurse anesthetists; RES, anesthesiology residents; SRNA, student nurse anesthetists.

Survey results revealed conflicts between what respondents thought was the right thing to do in terms of counseling patients and what they reported doing in practice (Figures 3 and 4; Supplemental Digital Content 3, Appendix 3, https://links.lww.com/AA/D415).


Most respondents, 121 of 154 (78%), affirmed that potential contraceptive failure after sugammadex exposure should always be discussed with patients preoperatively, rather than postoperatively (70% ATTG, 80% RES, 78% CRNA, 94% SRNA). Yet, only 50 of 154 (32%) reported often, almost always, or always discussing this drug interaction with at-risk patients preoperatively (Figure 3). Most respondents endorsed shared decision-making 133 of 154 (86%), but only 34 of 154 (22%) endorsed patient autonomy regarding the choice of NMB reversal agent (Figure 4). Yet, regarding clinical practice, almost all (137 of 154, 89%) reported rarely or never providing counseling and offering the patient a choice between neostigmine and sugammadex (Figure 3). Of note, most respondents (100 of 154, 65%) reported rarely or never inquiring about HC during preoperative interviews. Most (144 of 154, 94%), regardless of respondent gender, denied difficulty discussing this topic with female patients.

Intra- and Postoperatively

Despite the ability to avoid the sugammadex–HC drug interaction through the administration of neostigmine to reverse NMB, most respondents (121 of 154, 79%) reported rarely or never having done so with at-risk women (Figure 3). As for follow-up postoperatively, only 13 of 154 (8.4%) of providers described often, almost always, or always counseling patients on the sugammadex–HC drug interaction postoperatively, while 131 of 154 (85%) reported rarely or never reviewing the written patient warning/instructions form with at-risk patients before PACU discharge. Of note, the effectiveness of trainee instruction regarding this drug interaction was rated as imperfect by many—“poor” or fair by 41% ATTG, 57% RES, 40% CRNA, 33% SRNA. Likewise, many respondents rated as “poor” or “fair,” the effectiveness of communicating contraception recommendations by PACU nurses (43% ATTG, 54% RES, 35% CRNA, 28% SRNA) and by the discharge hand-out (30% ATTG, 37% RES, 28% CRNA, 33% SRNA).

Neuromuscular Monitoring and NMB Antagonism

We also queried participants regarding their use of and attitudes regarding neuromuscular monitoring to guide NMB administration and antagonism. Philips IntelliVue NMB monitors are available in all operating rooms and provide a train-of-four (TOF) count, as well as fourth to first twitch (T4/T1) TOF ratio, provided appropriate monitor calibration is performed before NMB administration in each patient. Despite availability of detailed, quantitative TOF ratio measurement, 133 of 165 (81%) reported the practice of not calibrating the device and utilizing only the TOF count to guide reversal of NMB ≥50% of the time. Overall, 22% (36 of 165) of respondents admitted that they omit NMB monitoring altogether at least half of the time when using sugammadex for antagonism (29% ATTG, 17% RES, 21% CRNA, 11% SRNA). Irrespective of their actual clinical practice, 76 of 154 (49%) of respondents indicated agreement or strong agreement with the statement, “the introduction of sugammadex has lessened the importance of precise quantitative NMB monitoring.” Finally, 21 of 154 (14%) agreed or strongly agreed that availability of sugammadex has made safe the use of rocuronium without quantitative NMB monitoring.


The decision to replace neostigmine with sugammadex as first-line NMB antagonist offered a unique opportunity to examine inadvertent consequences of an improvement initiative to prevent complications of postoperative residual NMB. Our approach to the manufacturer’s sugammadex–HC interaction risk warning and recommendations mirrored others,5–8 namely to inform women postoperatively of sugammadex exposure and recommend alternative contraception for 7 days. However, ex post facto counseling assumes providers’ accurate knowledge of HC use and potential interference by sugammadex. Most respondents reported rarely or never inquiring about contraception, and variable knowledge regarding potential for sugammadex interference with specific HCs. While almost all thought that sugammadex interferes with oral HC, only half thought it interferes with implantable (intramuscular, subcutaneous) HC delivery methods, while 44% indicated interference with levonorgestrel intrauterine contraception. Reasons for mixed responses may relate, in part, to inconsistency between warnings and recommendations and the intrauterine HC mechanism of action (local suppressive effect on endometrium).11 Although it is estimated that 40% of women between 15 and 44 years utilize HC,12 a study reported only 13.4% of 1000 women, ages 18–45, who received sugammadex at an academic center, had HCs documented in their charts.5 This discrepancy suggests that the absence of HC, especially nonoral formulations, from medication lists may hinder identification of at-risk women.

Although our policy requires that at-risk women be counseled, it does not specify by whom. Few respondents reported counseling themselves, yet many thought PACU nurses provided suboptimal counseling. O’Driscoll and Parrott13 demonstrated the vital importance of formally educating PACU nurses regarding the sugammadex–HC interaction,13 a process absent in our institution. Coincidentally, we discovered during manuscript preparation that in January 2020, a “go paperless” initiative eliminated the perioperative chart folder, which included the sugammadex exposure information form (the latter is still available in our medical record portal). Although sugammadex reversal readily became near universal after the policy change, no ongoing education reenforced patient counseling, nor were quality performance audits conducted, which may explain these findings.

When discharge counseling occurs, is the information provided accurate or effective? Nuanced contraceptive issues, like lesser effectiveness of barrier methods,14 are unaddressed in our discharge instruction form and unlikely discussed by nurses. It also cannot be assumed that patients fully understand and remember counseling. Although unstudied in postoperative patients, major understanding and recall deficits have been observed in patients discharged from emergency departments.15 Additionally, patients cannot be assumed to follow recommendations for unfamiliar alternative contraception following surgery.

Ex post facto counseling prioritizes superior NMB antagonism over ex ante shared decision-making that might allow for neostigmine use and obviate need to alter postoperative contraception.3,4 We previously argued an ethical case for either shared decision-making or paternalistic administration of neostigmine.3 Many respondents endorsed preoperative counseling and shared decision-making, consistent with the American College of Obstetricians and Gynecologists’ embrace of “reproductive justice.”16 Yet, respondents seldom report applying this approach to NMB antagonism in women of reproductive potential. Anesthesiology has long relied on quantitative research to guide evidence-based clinical decisions.17 Patient-centered care emerged as a coequal quality domain in 2001.18 Values-based practice recognizes that scientific progress opens up choices (eg, sugammadex or neostigmine), which bring a range of human values to bear. This latter framework is useful in resolving conflicts of value through processes supporting a balance of differing perspectives and promotion of shared decision-making.17 While some aspects of anesthesia care routinely involve informed patient choice (eg, blood transfusion, regional anesthesia), respondents rarely apply this approach to the sugammadex–HC interaction. That finding, along with drug interaction knowledge gaps, and respondents’ comments, suggested targeted education and strengthened policies that support shared decision-making may resolve the disconnect between what providers think they should do and what they actually do.

Finally, unlike SRNA trainees, who reported high levels of experience and confidence with neostigmine, the inexperience and lack of knowledge regarding neostigmine reported by residents, particularly among newer trainees, is concerning. This difference is likely explained by SRNA training at other hospitals, where neostigmine is commonly used, versus resident training limited to a single institution where it is not. When sugammadex is contraindicated, or neostigmine preferred, lack of familiarity with neostigmine may risk complications from its use, given its slower onset, time to achieve full effect, side effects, and need for accurate NMB monitoring. Cooper et al19 have reported medication errors in 1 per 200 anesthetics. Lack of knowledge, inexperience, and unfamiliar drug vials contributed to 11% of these errors. Self-reported unfamiliarity with neostigmine 2 short years after switching to sugammadex highlights the importance of educating trainees regarding applied pharmacology of neostigmine.

Although the unique institutional context of this study and the theoretical nature of the complication may limit application of our findings elsewhere, our study has strengths and transferable lessons. A 59%–64% response rate, optional comments indicating intentional reflection on survey content, and the fact that only 18% of respondents requested compensation suggest data trustworthiness. Regarding transferability, our findings may benefit institutions that have made or are considering making sugammadex the default antagonist, by raising awareness of potential barriers to effectively implementing policies to reduce theoretical risk of sugammadex-associated contraceptive failure and potential unintended knowledge gaps regarding neostigmine. Respondents’ endorsement of ex ante discussion and shared decision-making may prompt reconsideration of the ethics of standard ex post facto counseling regarding NMB antagonism for patients taking HCs. More broadly, our report highlights the importance of monitoring for unintended safety and education consequences of quality initiatives,20 and the need for ongoing education and performance monitoring following policy changes.

In conclusion, we identified several barriers contributing to failure by most anesthesia providers to ensure recommended postsugammadex exposure contraception counseling for at-risk women. These include incomplete/inaccurate provider knowledge of sugammadex–HC interaction and manufacturer recommendations, omission of contraception screening questions during preanesthetic interviews, and lack of personal involvement in postoperative counseling. Our findings revealed discordance between anesthesia providers’ thoughts and actions vis-à-vis preanesthetic counseling and shared decision-making in selection of NMB antagonist, as it relates to risk of sugammadex-associated HC failure. Trainee-reported lack of knowledge and experience administering neostigmine was an unintended consequence of designating sugammadex as NMB antagonist of choice.


The authors are grateful to Ms Martha W. Tanner, Department of Anesthesiology, Vanderbilt University Medical Center, for her meticulous copyediting and assistance in preparing this manuscript.


Name: Robyn L. Dwan, DO.

Contribution: This author helped design the study, construct the survey instrument, statistically analyze the data, and draft the manuscript.

Name: Britany L. Raymond, MD.

Contribution: This author helped design the study, construct the survey instrument, statistically analyze the data, and draft the manuscript.

Name: Michael G. Richardson, MD.

Contribution: This author helped design the study, construct the survey instrument, statistically analyze the data, and draft the manuscript.

This manuscript was handled by: Jill M. Mhyre, MD.


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