ISSN NUMBER: 1938-7172
Issue 10.1 VOLUME 10 | NUMBER 1

Editor:
Michael A. Fiedler, PhD, CRNA

Contributing Editors:
Mary A Golinski, PhD, CRNA
Dennis Spence, PhD, CRNA
Steven R Wooden, DNP, CRNA, NSPM-C

Assistant Editor
Jessica Floyd, BS

A Publication of Lifelong Learning, LLC © Copyright 2016

New health information becomes available constantly. While we strive to provide accurate information, factual and typographical errors may occur. The authors, editors, publisher, and Lifelong Learning, LLC is/are not responsible for any errors or omissions in the information presented. We endeavor to provide accurate information helpful in your clinical practice. Remember, though, that there is a lot of information out there and we are only presenting some of it here. Also, the comments of contributors represent their personal views, colored by their knowledge, understanding, experience, and judgment which may differ from yours. Their comments are written without knowing details of the clinical situation in which you may apply the information. In the end, your clinical decisions should be based upon your best judgment for each specific patient situation. We do not accept responsibility for clinical decisions or outcomes.

Table of Contents

AIRWAY
First-attempt intubation success of video laryngoscopy in patients with anticipated difficult direct laryngoscopy: a multicenter randomized controlled trial comparing the C-MAC D-Blade vs. the GlideScope in a mixed provider and diverse patient population
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Early endotracheal tube insertion with the Glidescope: a randomized controlled trial
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OBSTETRIC ANESTHESIA
Randomized trial of labor induction in women 35 years of age or older
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PATIENT SAFETY
Capnographic monitoring in routine EGD and colonoscopy with moderate sedation: a prospective, randomized, controlled trial
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QUALITY IMPROVEMENT
Evaluation of perioperative medication errors and adverse drug events
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REGIONAL ANESTHESIA
A smartphone-based decision support tool improves test performance concerning application of the guidelines for managing regional anesthesia in the patient receiving antithrombotic or thrombolytic therapy
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None of the editors or contributors have any real or potential conflicts of interest to disclose.


Airway
First-attempt intubation success of video laryngoscopy in patients with anticipated difficult direct laryngoscopy: a multicenter randomized controlled trial comparing the C-MAC D-Blade vs. the GlideScope in a mixed provider and diverse patient population

Anesth Analg 2016;122:740-50

Aziz MF, Abrons RO, Cattano D, Bayman EO, Swanson DE, Hagberg CA, Todd MM, Brambrink AM


Abstract

 

Purpose The purpose of this study was to determine if the rate of first-attempt intubation success was similar when using the C-MAC D-Blade vs. the GlideScope in patients with anticipated difficult airways.

 

Background Video laryngoscopy is considered by many the go-to device for anticipated or unanticipated difficult airways. The GlideScope (Verathon, Bothell, WA), has been on the market the longest; however, a new indirect video laryngoscopy device called the C-MAC D-Blade (Karl Storz. Tuttlingen, Germany) has recently come on the market. Currently it is unknown if similar success is found with both devices in anticipated difficult airways.

 

Methodology This was a multi-center, randomized controlled trial designed to compare first-intubation success with the C-MAC video laryngoscope and D-Blade to the GlideScope video laryngoscope with a number 4 blade in patients with an anticipated difficult airway. The study took place in three academic centers in different states. The investigators hypothesized that in this population that the C-MAC D-Blade first-attempt intubation success would be noninferior (not unacceptably less successful) to the GlideScope no. 4 blade.

 

Patients were randomized to have intubation performed with either the C-MAC D-Blade or GlideScope no. 4 blade. Inclusion criteria were:

  • Mallampati class III or IV
  • mouth opening <3 cm
  • large neck circumference (>40 cm males & >38 cm females)

Exclusion criteria were:

  • history of easy intubation
  • history of failed intubation
  • history of failed mask ventilation
  • unstable c-spine
  • mouth opening < 2 cm

Anesthesia providers who participated were educated on both devices in a simulation center and were required to have video laryngoscopy experience and at least 6 months of clinical anesthesia training. Anesthetic induction agent was at the discretion of the anesthesia provider but included the administration of either succinylcholine or rocuronium. Intubation was attempted after resolution of fasiculations or after 90 seconds with succinylcholine or when the train-of-four measured at the ulnar nerve receded to 1 to 2 twitches when rocuronium was administered. The GlideScope stylet was used for all intubations and endotracheal tube size was at the discretion of the anesthesia provider.

 

The primary outcome was first-attempt intubation success, defined as confirmation of persistent end-tidal carbon dioxide with a single blade insertion and without blade manipulation of the laryngoscope by another provider. Laryngeal manipulation could be performed. Other outcomes included time to intubation, best laryngeal view obtained, and complications. The investigators assumed any difference of <4% in first-intubation success in the upper bounds of the 90.4% confidence interval would be an acceptable margin to conclude comparable device performance and thus, that the C-MAC D-Blade was noninferior to the GlideScope no. 4 blade.

 

Result There were 1,101 patients who completed the study (C-MAC n = 550 and GlideScope n = 551). Clinical characteristics were similar between the two groups. Overall, 55% of patients had a Mallampati III or IV exam, 91% had a neck circumference >40 cm, and 1.2% had a mouth opening <3 cm.

 

First-attempt intubation success in the GlideScope group was 96.2%. First-attempt intubation success in the C-MAC D-Blade group was 93.4%. Since the upper 90.4% confidence interval difference between the two devices was 4.8%, the C-MAC D-Blade was considered to be inferior with regards to first-attempt intubation success compared to the GlideScope (Table 1). In the GlideScope group, 14 patients who were not intubated on the first attempt were successfully intubated with the GlideScope on subsequent attempts; 4 patients with direct laryngoscopy, 1 with the C-MAC, 1 with a fiberoptic bronchoscope, and in 1 patient a supraglottic airway was placed. In the C-MAC D-Blade group, 25 patients were successfully intubated with a second attempt with the C-MAC, 3 with the GlideScope, 1 with a fiberoptic bronchoscope, and 1 with another type of video laryngoscopy device.

 

No differences were found in the first-attempt time to intubation (Table 1). The glottic view was significantly better in the C-MAC D-Blade group (Table 1). Complications such as lip injury, SpO2 <90%, etc. were similar between groups. The rate of airway trauma was 12.7% in the GlideScope group and 14.6% in the C-MAC D-Blade group (P = NS).

 

Table 1. Differences in Intubation Success

 

GlideScope

(n = 551)

C-MAC

(n = 550)

Upper bounds of 90.4% CI of difference

First-attempt success

96.2%

93.4%

4.98%

First attempt success by providers with >5 prior uses of the study device

96.1%

93.8%

4.68%

First-attempt success for patients with multiple predictors

95.6%

94.2%

4.16%

First-attempt success within 90 s while SpO2 >95%

94.3%

90.5%

6.52%

Success rate for multiple attempts

98.4%

98.3%

1.32%*

First-attempt time to intubation (seconds)

47

47

P = NS

Best Laryngeal View

Grade 1

Grade 2

Grade 3

Grade 4

 

72.1%

26.5%

1.5%

0.4%

 

88%

7.5%

1.5%

1.8%

P < 0.0001

Note: Significant differences were found in the grade view, favoring the MAC-C (P < 0.0001). No significant differences in time to intubation were found. *Noninferior. CI = confidence interval.

 

Conclusion In a head-to-head comparison, the C-MAC D-Blade had a lower first-attempt intubation success than the GlideScope. However, overall intubation success rates were very high with both systems when used in patients with a potentially difficult airway.

 

Comment

Indirect video laryngoscopy devices have really changed the way we approach difficult airways. Nowadays when I have a potentially difficult airway I go straight to the GlideScope (because that is we the device we have). If all I had were the C-MAC D-Blade I would probably use it. The differences are not clinically significant and are probably related to the fact that the GlideScope has been available for a much longer time than the C-MAC D-blade. Thus, anesthesia providers have more experience with the GlideScope.

 

What was interesting was the C-MAC D-Blade provided a better glottic view (88% vs. 72%). It is possible that this may have contributed to the slightly lower first-attempt intubation success. With the GlideScope you actually want more of a grade 2 view because this makes it easier to pass the ETT into the glottis.

 

Dennis Spence, PhD, CRNA


The views expressed in this article are those of the author and do not reflect official policy or position of the Department of the Navy, the Department of Defense, the Uniformed Services University of the Health Sciences, or the United States Government.


© Copyright 2016 Anesthesia Abstracts · Volume 10 Number 1, January 30, 2016





Early endotracheal tube insertion with the Glidescope: a randomized controlled trial

Anesth Analg 2016;122:753-7

Turkstra TP, Cusano F, Fridfinnson JA, Batohi P, Rachinsky M


Abstract

 

Purpose The purpose of this study was to compare time to intubation with a Glidescope-video laryngoscopy when the endotracheal tube (ETT) was inserted before or after the Glidescope was inserted.

 

Background The incorporation of video laryngoscopy into clinical practice has revolutionized the approach to difficult airway management. However, one of the challenges, specifically with the Glidescope, is difficulty navigating the endotracheal tube (ETT) into the glottis. Some anesthesia providers insert the ETT into the pharynx before inserting the Glidescope when approaching a difficult airway. The ETT-first technique involves carefully inserting a styletted ETT, typically with a 90 degree bend 8 cm from the end of the ETT, into the pharynx while manually holding the mouth open. Next the Glidescope is gently inserted into the pharynx and a view of the glottis is obtained. The ETT is usually directly in the field of view and can be easily inserted through the glottis into the trachea. Unfortunately, no randomized controlled trials have compared the efficacy of ETT-first vs. Glidescope-first on time required for intubation.

 

Methodology This was a prospective, randomized, controlled trial at three teaching hospitals in Canada. Exclusion criteria included a known or suspected difficult airway, cervical spine abnormality, and patients requiring rapid sequence intubation. Anesthesia providers included staff anesthesiologists and third year anesthesia residents. Each provider had performed at least three ETT-first intubations before participating in the study.

 

Adult patients undergoing elective surgery were enrolled. For all intubations, providers used a size 4 Glidescope, a Mallinckrodt Hi-Lo ETT and a 14F stylet which was bent to the provider’s preferred angulation. Typically this was a 90 degree bend at 8 cm. During induction all patients received 0.6 mg/kg rocuronium. Other induction agents administered were at the discretion of the anesthesia provider. Intubation began 90 seconds after administration of the rocuronium. No twitch monitor was used. The provider was unaware of the group assignment up until this point. Next, a research assistant opened an envelope and told the provider the group assignment ETT-first or Glidescope-first. As soon as the face mask was removed, intubating time began. Intubation was defined as presence of at least 20 cm H2O end-tidal CO2. After intubation the anesthesia provider rated the laryngoscopic grade view, ease of intubation (scored on a 0-100 mm scale; 0 = easy, 100 = difficult), and presence of blood with suctioning after intubation (rated as none, mild, moderate, or severe). Sample size calculations and statistical analysis were appropriate. A P< 0.05 was considered significant.

 

Result There were 80 patients enrolled in each group. No significant differences were found in patient characteristics; 21% in the ETT-first group and 19% in the Glidescope-first group had a Mallampati III airway exam. No significant differences were found in time to intubation between the ETT-first and Glidescope-first groups (48 sec vs. 52 sec). Ease of intubation scores were also similar. Only 1 subject in the ETT-first and Glidescope-first groups had a Grade III view, and 1 subject in the Glidescope-first had a grade IV view (P = NS). No significant differences were found in the number of intubation attempts. In the ETT-first group 3 patients required two attempts and 1 patient required three attempts. In the Glidescope-first group 5 patients required two attempts and 1 patient required three attempts at intubation.

 

Conclusion There were no significant differences in mean time to intubation, grade view, ease of intubation, or presence of blood after intubation when either the ETT or Glidescope blade was first inserted first into the oropharynx.

 

Comment

I thought this was a novel study. One of the most frustrating things with a Glidescope intubation is having a great view of the glottis but not being able to navigate the ETT into the trachea. I would never have thought to place the ETT in the oropharynx before placing the Glidescope blade. But it makes sense it would work because it presumably aligns the ETT with the glottic opening.

 

My concern with the ETT-first technique would be airway trauma. However, the investigators in this study reported the time to intubation was similar and that the amount of blood present was the same; although, blood was more often noted after suctioning in the ETT-first group (11% vs. 4%). The investigators did state that there was no difference in complaints of vocal changes or sore throat between the two groups. I did not report these results above because other factors, such as intracuff pressure, could affect these outcomes. It does not surprise me that they found a slightly higher amount of blood in the airway in the ETT-first group, given the ETT was placed blindly.

 

So I think this might be a useful technique to add to one’s airway “toolbox.” I would recommend being very gentle in placing the ETT and would probably use the stylet that comes with the Glidescope (but that is my personal preference) if I had trouble placing the ETT on the first or second intubation attempt.

 

Dennis Spence, PhD, CRNA


The views expressed in this article are those of the author and do not reflect official policy or position of the Department of the Navy, the Department of Defense, the Uniformed Services University of the Health Sciences, or the United States Government.


© Copyright 2016 Anesthesia Abstracts · Volume 10 Number 1, January 30, 2016




Obstetric Anesthesia
Randomized trial of labor induction in women 35 years of age or older

N Engl J Med 2016; 374: 813-22

Walker K, Bugg GJ, Macpherson M, McCormick C, Grace N, Wildsmith C, Bradshaw L, Smith GCS, Thornton JG, for the 35/39 Trial Group


Abstract

 

Purpose The purpose of this study was to determine if induction of labor at 39 weeks gestation reduced the rate of cesarean delivery in nulliparous women ≥35 years old.

 

Background In industrialized nations there is an increasing rate of nulliparous women giving birth at 35 years of age or older; termed “advanced maternal age.” Unfortunately, rates of perinatal death, hypertensive disorders, gestational diabetes, placenta previa, and placental abruption are higher in women who are of advanced maternal age. Additionally, the rates of obstetric interventions such as induction of labor or cesarean delivery are higher in these women. In the United Kingdom the rate of cesarean delivery is 38% in nulliparous women ≥35 years old (Contributing Editor’s Note: similar rates are found in the United States). Rates of emergency cesarean delivery are strongly correlated with increasing maternal age.

 

Current recommendations suggest that induction of labor should generally only be performed before 41 weeks gestation for maternal or fetal indications. Otherwise, induction should only be performed after 41 weeks to reduce the risk of cesarean delivery and perinatal morbidity and mortality. Induction of labor is associated with increased complications:

  • uterine atony
  • postpartum hemorrhage
  • prolapsed cord
  • increased risk of cesarean delivery

Some obstetricians will induce at 40 weeks, while others do not out of concern for increased complications in older parturients. However, in studies of younger nulliparous women, higher rates of cesarean delivery have not been reported with labor induction. Anecdotal reports suggest cesarean delivery rates may not be higher in nulliparous advanced maternal age women. Given these conflicting findings, the investigators sought to compare rates of cesarean delivery in nulliparous advanced maternal age women undergoing elective induction of labor between 39 weeks and 0 days and 39 weeks 6 days vs. expectant management.

 

Methodology This was a multicenter, randomized, controlled trial performed in the United Kingdom. Nulliparous women who were 35 years of age or older were randomized to elective induction of labor between 39 weeks and 0 days and 39 weeks 6 days (induction group) vs. expectant management (waiting for labor to start spontaneously). unless a situation developed necessitating delivery either through induction of labor or cesarean delivery). Exclusion criteria included:

  • multiple gestation
  • fetal congenital anomaly
  • fetal compromise
  • placenta previa
  • expectant management contraindicated

Women in the expectant management group could be induced between 41 and 42 weeks at the discretion of their obstetrician or midwife. Each facility was encouraged to use a similar induction protocol for all patients.

 

The primary outcome was the rate of cesarean delivery. Secondary outcomes included:

  1. method of delivery
    1. unassisted vaginal delivery
    2. assisted vaginal delivery
  2. onset of labor
    1. spontaneous
    2. elective induction
    3. emergent cesarean
    4. no labor
  3. reason for induction
  4. peripartum & neonatal complications

Rates of postpartum hemorrhage, >500 mL for vaginal delivery and >1,000 mL for cesarean delivery, and need for blood transfusion were recorded. Investigators hypothesized elective induction of labor would reduce the rate of cesarean delivery by 9% when compared to expectant management.

 

Result There were 305 women in the induction group and 314 in the expectant management group. No significant differences were found in baseline characteristics between the two groups. Average age was 37 years (range 35-45), BMI was 27 kg/m2.

 

In the induction group 87% of women completed the study in their assigned group compared to 95% of women in the expectant management group. The frequency of cesarean delivery was similar in the induction and expectant management groups (32% vs. 33%). Rates of cesarean delivery increased as the patient’s age increased irrespective of group (Figure 1). Indications for cesarean delivery were similar as were rates of complications. The rate of assisted vaginal delivery was slightly higher in the induction group vs. the expectant group; 38% vs. 33% (P = NS). The use of epidural analgesia was similar in both groups; 35% vs. 29%.

 

Figure 1. Cesarean Delivery Rates

Figure 1

 

The postpartum hemorrhage rate was 31% (n = 95/304) in the induction group and 29% (n = 90/314) in the expectant management group (P = NS). Overall, however, only 3.2% and 5.4% of women required a blood transfusion. No differences in neonatal outcomes were found between the two groups.

 

Conclusion Induction of labor at 39 weeks of gestation did not decrease the rate of cesarean delivery, assisted vaginal delivery, or adverse maternal or neonatal outcomes compared to expectant management.

 

Comment

Some of you are probably wondering why I chose to review an obstetric article that has nothing directly to do with anesthesia. I think it is important that obstetric anesthesia providers keep up with the current literature in obstetrics, not just obstetric anesthesia. Staying current in our colleagues’ area helps inform our practice and aids in our communication with our obstetricians and midwives. When I teach students I encourage them to read the excellent Obstetric Consensus guidelines published by the American College of Obstetricians and Gynecologists that reviews how to safely prevent primary cesarean delivery.1 This article provides a nice overview of how obstetricians manage their laboring patients.

 

Knowing the indication for induction of labor is important because it may impact our management of a labor deck. For example, maybe a patient is being admitted for severe preeclampsia at 34 weeks and is showing a down trending platelet count. We might want to interview that patient and develop a plan early in consultation with the obstetrician. Whereas, if you have a woman coming in for an elective induction at 39 weeks, you might wait to see her until you have taken care of the sicker patient. Having situational awareness and knowing how to prioritize care is critical on an obstetric unit.

 

So what about this study? Well, the authors’ hypothesis was not supported. Induction at 39 weeks did not decrease the cesarean delivery rate. In fact, the rate was virtually the same. The results do suggest, at least for delivery and neonatal outcomes, that induction is safe. Do I expect in the U.S. that we will see this change induction practices? Probably not.

 

What I found most interesting was the postpartum hemorrhage rates. They were similar, but a large number of patients in the expectant management group required induction for some maternal or fetal indication. Induction of labor is associated with increased rates of uterine atony, especially when >24 hours. In this study about a third of patients experienced a postpartum hemorrhage, and overall between 3% and 5% required a blood transfusion. If one assumes only those who had a postpartum hemorrhage were transfused, then up to 15% of those patients required a transfusion. This is not a low number and speaks to the importance of having situational awareness and making oneself available to help with resuscitations after a postpartum hemorrhage. As anesthesia providers who are experts in resuscitation, we can help reduce complications from blood transfusion by helping to develop massive hemorrhage protocols and ensuring our fellow anesthesia providers stay up-to-date on these protocols.

 

Dennis Spence, PhD, CRNA


1. Obstetric Care Consensus: Safe Prevention of the Primary Cesarean Delivery. The American College of Obstetricians and Gynecologists. https://www.acog.org/-/media/Obstetric-Care-Consensus-Series/oc001.pdf?dmc=1&ts=20160315T1650041862. Published March 2014. Accessed April 22, 2016.

 

The views expressed in this article are those of the author and do not reflect official policy or position of the Department of the Navy, the Department of Defense, the Uniformed Services University of the Health Sciences, or the United States Government.


© Copyright 2016 Anesthesia Abstracts · Volume 10 Number 1, January 30, 2016




Patient Safety
Capnographic monitoring in routine EGD and colonoscopy with moderate sedation: a prospective, randomized, controlled trial

Am J Gastroenterol 2016;111:395-404

Mehta PP, Kochhar G, Albeldawi M, Kirsh B, Rizk M, Putka B, John B, Wang Y, Breslaw N, Lopez R, Vargo JJ


Abstract

 

Purpose The purpose of this study was to compare differences in hypoxemia (SaO2 <90% for 10 s) in patients undergoing esophogastroduodenoscopy (EGD) and colonoscopy randomized to capnography (ETCO2) monitoring vs. standard monitoring without ETCO2.

 

Background Capnography (ETCO2) allows for earlier detection of respiratory depression than pulse oximetry (SaO2). In 2010, the American Society of Anesthesiologists published standards of basic anesthetic monitoring recommending continuous ETCO2 for procedures requiring moderate or deep sedation (Contributing Editor’s Note: the AANA has a similar standard). However, there are increased costs and training associated with ETCO2 use for routine EGD and colonoscopy procedures during nurse-administered moderate sedation. According to the authors of this manuscript, there is no randomized evidence to support improved patient safety with the use of ETCO2 for moderate sedation procedures during outpatient EGD and colonoscopy procedures in ASA I or II patients receiving traditional sedatives and opioids such as midazolam, meperidine, and fentanyl.

 

Methodology This was a single-center, prospective, randomized, blinded trial of patients undergoing either EGD or colonoscopy. Inclusion criteria were: ASA I or II and aged 18 years or older. Exclusion criteria were: ASA III or higher or history of diagnosed obstructive sleep apnea. Patients were randomized into either a capnography blinded group in which ETCO2 information was not available to the sedation nurse or physician (ETCO2 No) or a group in which ETCO2 information was available to the sedation nurse and physician (ETCO2 Yes).

 

Staff in the ETCO2 No group received no ETCO2 information during the procedure except when unrecognized apnea ≥30 s occurred. The endoscopist, sedation nurse, and room technicians were all blinded to the ETCO2 information.

 

In the ETCO2 Yes group data collection personnel announced to the room “not breathing properly” or “patient not breathing” in response to respiratory abnormalities on the ETCO2 monitor, including:

  • Hypoventilation defined as a respiratory rate ≤8
  • Apnea defined as a flatline or respiratory rate of 0 for ≥5 s
  • Disordered respirations defined as a ≥75% reduction from baseline capnographic waveform lasting ≥10 s
  • Pseudo apnea defined as the capnography monitor showing a flatline or apnea and the subject was subsequently found to be breathing or holding their breath

 

Sedation was initiated with midazolam 2 mg and either fentanyl 50 µg or meperidine 50 mg IV. Two minutes after initial sedation, the sedation nurse could titrate medications to effect to achieve moderate sedation. All patients were monitored with SaO2, EKG, BP, and visual assessment by experienced sedation nurses. Nasal cannula oxygen was not administered unless baseline SaO2 <90%. When hypoxemia occurred (SaO2 <90%), the nurse would tap the patient’s forehead or speak to them. If that did not correct the hypoxemia, then oxygen was administered. 

 

Primary Outcome

  • Hypoxemia: SaO2 ≤90% for ≥10 s

Secondary Outcomes

  • Severe hypoxemia: SaO2 <85% at any time during procedure
  • Hypoventilation: respiratory rate ≤8
  • Apnea: flatline or respiratory rate of 0 for ≥5 s)
  • Early procedure termination for any reason

 

EGD and colonoscopy patients were analyzed separately. A P < 0.05 was considered significant.

 

Result There were 209 EGD patients (No ETCO2 = 108 vs. Yes ETCO2 = 101). No significant differences were found in baseline characteristics, procedure time (average: 6 min), midazolam dose (average: 4 mg), fentanyl dose (average: 1.2 µg/kg), or meperidine dose (average: 95 mg).

 

In EGD patients, no differences were found in the rate of hypoxemia (SaO2 <90%) between the No ETCO2 and Yes ETCO2 groups (55% vs. 54%). There was also no difference in the rate of severe hypoxemia; SaO2 85% (17% vs. 21%), disordered respiration (13% vs. 11%) or hypoventilation (13% vs. 12%). Interestingly, the rate of apnea was significantly higher in the Yes ETCO2 group compared to the No ETCO2 group (58% vs. 43%; P = 0.02).

 

In EGD patients, multivariate analysis demonstrated that patients with lower baseline oxygen saturations  and higher diastolic blood pressure were more likely to experience an episode of hypoxemia after adjusting for gender and fentanyl and midazolam dosing. The absolute risk reduction for hypoxemia associated with the use of ETCO2 during EGD was 4.6% (P = NS). A number needed to treat analysis showed that one patient in every 22 would benefit from ETCO2 monitoring. For severe hypoxemia, the absolute risk reduction associated with the use of ETCO2 was 2.8%. Here 37 patients would need ETCO2 monitoring to prevent one patient from experiencing severe hypoxia.

 

There were 231 patients in the colonoscopy group (No ETCO2 = 114 vs. Yes ETCO2 = 117). No significant differences were found in baseline characteristics, procedure time (average: 17 min), midazolam dose (average: 4 mg), fentanyl dose (average: 1 µg/kg), or meperidine dose (average: 71 mg).

 

In colonoscopy patients, no differences were found in the rate of hypoxemia (SaO2 <90%) between the No ETCO2 and Yes ETCO2 groups (54% vs. 52%). Similar rates were found for disordered respiration (26% vs. 30%), and hypoventilation (17% vs. 16%). However, the rate of severe hypoxemia (SaO2 <85%) was significantly higher in the No ETCO2 group compared to the Yes ETCO2 group (18% vs. 5%; P = 0.002). While not significant, a higher rate of apnea was also observed in the No ETCO2 group (63% vs. 56%).

 

In colonoscopy patients, multivariate analysis demonstrated that patients with higher body mass index (BMI) and lower baseline oxygen saturations were associated with an increased likelihood of hypoxemia after adjusting for sedation. For severe hypoxemia, increasing BMI and higher fentanyl dose were associated with an increased rate of severe oxygen desaturation (<85%). Being randomized to the Yes ETCO2 group significantly decreased the odds a patient would experience severe hypoxemia (OR = 0.24, P = 0.004). After adjusting for BMI and fentanyl dosing, patients in the Yes ETCO2 group were 76% less likely to have an episode of severe hypoxemia compared to the No ETCO2 group.

 

For severe hypoxemia, the absolute risk reduction associated with the use of ETCO2 was 12.8% meaning 1 patient in every 8 would benefit from ETCO2 monitoring.

 

Conclusion The use of ETCO2 during outpatient EGD and colonoscopy in ASA I & II patients did not appear to lower the rate of hypoxemia. However, use of ETCO2 may be of benefit in obese patients undergoing colonoscopy.

 

Comment

I have spent some time reviewing the gastroenterology literature and reading community discussion boards on the use of ETCO2 during outpatient EGD and colonoscopy procedures in ASA I and II patients. I must say, my perception is that some gastroenterologists see no benefit in the use of ETCO2 during nurse-administered sedation (no propofol) and feel the higher cost is not justified. Unfortunately, some gastroenterologists will probably cite this study as a reason for NOT needing to use ETCO2 in this patient population.

 

In the abstract published by the authors, they concluded that ETCO2 monitoring in this population does not reduce the incidence of hypoxemia. Based on their findings, they are correct; however, they failed to state that the rate of severe hypoxemia was significantly reduced when ETCO2 was used during colonoscopy, especially in obese patients. You have to read the whole manuscript to discover this finding. I find their conclusion to be a biased representation of the findings of this study.

 

The findings of this study are not generalizable. All nurses and gastroenterologists were blinded to ETCO2 data and were only told by an investigator whether or not the patient was not breathing. This design is not clinically relevant because a nurse administering the sedation would be using the ETCO2 combined with the other clinical data to correct any hypoventilation and hypoxemia. Another limitation is that the authors did not report if any patients required oxygen administration. Also there may have been some baseline differences in the EGD group, which biased the results. Additionally, monitoring ETCO2 during EGD can be challenging, especially during scope placement. Patients are often coughing and moving, and many times the pulse oximeter may not be accurate. These procedures are also shorter. Also the investigators should have collected STOP-BANG data on patients, as I suspect some may have had undiagnosed Obstructive Sleep Apnea, given BMI was associated with severe hypoxemia during colonoscopy. These issues combined with the study design make me less confident in the study findings.

 

If anything, the results demonstrate the use of ETCO2 decreases the rate of severe hypoxemia during colonoscopy, especially in obese patients. I recommend anesthesia providers help educate and train nurses and gastroenterologists on the use of capnography during moderate sedation. As nurses gain more experience using capnography, I suspect they will find its use of benefit during EGD and colonoscopy procedures.

Dennis Spence, PhD, CRNA


The views expressed in this article are those of the author and do not reflect official policy or position of the Department of the Navy, the Department of Defense, the Uniformed Services University of the Health Sciences, or the United States Government.


© Copyright 2016 Anesthesia Abstracts · Volume 10 Number 1, January 30, 2016




Quality Improvement
Evaluation of perioperative medication errors and adverse drug events

Anesthesiology 2016;124:25-34

Nanji KC, Patel A, Shaikh S, Seger DL, Bates DW


Abstract

 

Purpose The purpose of this study was to describe the rate, types, severity, and preventability of anesthesia provider medication errors and adverse drug events in an operating room setting.

 

Background Drug administration errors are one of the most frequently cited critical incidents in anesthesia. Unfortunately, little is known about actual rates of anesthesia provider medication errors and adverse drug events. New technology, such as barcode-assisted syringe labeling systems are purported to reduce medication errors but are rarely used in the operating room. This study sought to examine anesthesia provider medication errors and adverse drug events in a facility that uses barcode-assisted syringe labeling systems in the operating room and to generate recommendations for the prevention of these events.

 

Methodology This study took place at a site which performed 40,000 operations annually in 64 anesthetizing locations. Each operating room included a barcode-assisted syringe labeling system which included the drug name, strength, quantity, expiration date, and the providers’ initials. The system provided audio and visual read-back of the drug name and concentration. Each operating room also included an electronic anesthesia information management system. Participants included 81 anesthesiologists, 53 CRNAs, and 103 residents.

 

The research team developed definitions based on the review of the medication administration process and published literature. The medication administration process consisted of: requesting, dispensing, preparing, administering, documenting, and monitoring.

 

A medication error was defined as failure to complete a required action in the medication administration process.

 

An adverse drug event was defined as patient harm or injury due to a drug related intervention, regardless of whether an error in the medication administration process occurred.

 

Four trained observers (3 anesthesiologists and 1 CRNA) independently observed medication administration and reviewed the medical records to identify additional events. Event severity was defined as life-threatening (e.g., patient with a history of anaphylaxis with penicillin is given penicillin or cefazolin), serious (e.g., failing to administer antibiotics before skin incision; patient given insulin but blood glucose not rechecked), or significant (e.g., blood glucose not checked in a patient with diabetes). For example, moderate hypotension after induction with propofol in patients with no cardiac risk factors was excluded as an adverse drug event. However, a MAP <55 mm Hg after induction with propofol in a patient with cardiac risk factors was classified as an adverse drug event. Events were classified as preventable or not preventable.

 

Result Over 8 months, 226 providers participated; 74 [33%] anesthesiologists, 51 [23%] CRNAs, and 101 [45%] residents. There were 193 events detected, most (80%) through direct observation. A single event could involve both a medication error and an adverse drug event. Of 3,671 medication administrations there were:

  • 153 medication errors
  • 91 adverse drug events

 

The rate of medication error/adverse drug event was 5.3%. Overall, the rate of medication errors was 4.1% and the rate of adverse drug events was 2.4%. Summaries of the events are described in the following Figures.

 

Figure 1. Rate of Medication Errors & Adverse Drug Events

Figure 1

Note: ADE = Adverse Drug Event.

 

Figure 2. Severity of Adverse Drug Events

Figure 2

 

Of these events, 79% were deemed preventable. Over half the events (54%) occurred within 20 minutes of induction. None of the events were fatal, 3 (1.6%) were life-threatening, 133 (69%) serious, and 57 (30%) were significant. The most common medication error which led to an adverse drug event was inappropriate doses (47%; e.g., 1 mg remifentanil bolus in 86 patients), and omitted medications/failure to act (31%; e.g., failure to redose antibiotics after 4 hours in a long case). Other examples are listed in Table 1. Medications most commonly associated with medication errors were:

  • propofol (26%)
  • phenylephrine (10%)
  • fentanyl (9%)

There were no differences in medication errors or adverse drug events by provider type. Procedures >6 hours had higher event rates (P < 0.05), as did procedures with 13 or more medication administrations (P < 0.05).

 

Table 1. Medication Errors and Examples of Associated ADEs

Error Type (N = 153)

Error Example

Potential ADE

Labeling error (24%)

No phenylephrine label

Syringe swap and too large a dose given leading to hypertension

Wrong dose (23%)

1 mg remifentanil given to 87 kg patient

Bradycardia and hypotension

Omitted medication (18%)

Failure to administer preoperative antibiotics in timely manner

Potential surgical site infection

Documentation error (17%)

Intubation not documented

Airway trauma or hypoxia due to unexpected difficult intubation

Monitoring error (6%)

No blood pressure check prior to induction

BP>200 mm Hg on first check after induction

Wrong medication (6%)

Provider wanted to give ondansetron but when they withdrew the medication from slot they discovered it was phenylephrine

Severe hypertension

Wrong timing (3%)

Delay in treating post-induction hypotension

Organ hypoperfusion

Inadvertent bolus (1%) 

Phenylephrine infusion connected distal to antibiotics

Hypertension

Other (1%)

Syringe of hydromorphone left unattended

Drug diversion

Note: ADE = Adverse Drug Event.

 

The authors offered technology-based and process-based solutions that could have prevented the medication errors/adverse drug events. The authors speculated that 17% of medication errors and 26% of potential adverse drug events could have been prevented with technology-based interventions like point-of-care barcode-assisted anesthesia documentation systems. Specific drug decision support software and alerts would have prevented 29% of medical errors, 14% of potential adverse drug events, and 59% of adverse drug events. Real-time alerts would have prevented 53% of medication errors, 32% of potential adverse drug events, and 94% of adverse drug events.

 

Process-based interventions such as automatic timing of documentation when a drug is administered (i.e., linked to the syringe scanning system) could have eliminated 35% of the medication errors, 22% of potential adverse drug events, and 63% of adverse drug events. Reducing workarounds (i.e., only able to label syringes with barcode-assisted labeling systems) would have eliminated 24% of medication errors and 36% of potential adverse drug events.

 

Conclusion Approximately 1 in 20 medication administrations resulted in a medication error and/or potential or actual adverse drug event. Almost 30% of these errors lead to patient harm.

 

Comment

Here is a hypothetical scenario. At the last minute you decide to administer a TIVA with remifentanil and propofol to a patient with severe PONV. You quickly prepare the infusions. When the patient arrives in the room you open the fluids and are preparing to induce the patient when you notice she has become apneic. You quickly realize you had forgotten to place the remifentanil on the infusion pump and had inadvertently opened that line rather than the lactated ringers line. You quickly give some ephedrine to treat the hypotension and proceed quickly with your induction and administer propofol and succinylcholine. The patient is easily intubated and no complications occur. I wonder how many anesthesia providers have had something similar happen. Could the use of some of the solutions offered by the authors in this study prevent this event? Possibly.

 

We work in a very dynamic and rapidly changing environment where we sometimes have to respond very quickly. It is easy to grab the wrong syringe. I like to think our experience, attention to detail, and vigilance can prevent medication errors, but in reality it does not always do so. This study was important because it helps highlight a very real patient safety concern. I wonder what the rate of medication errors and adverse event events are at institutions that do not use barcode-assisted syringe labeling systems, anesthesia information management systems, or have prefilled syringes. I imagine the rates are higher.

 

So what should we do? Get our facilities to purchase these very expensive systems? Well, in reality that is probably not going to happen. A few years ago we switched to prefilled syringes and I think that helped reduce some mistakes. I think we need to continue to be vigilant, especially during and after induction. Place reminders on the anesthesia machine reminding you to redose the antibiotics or recheck the blood sugar. While not directly related, when a surgeon places a throat pack, I tape a piece of gauze to the anesthesia machine as a reminder and remove it when the surgeon removes it at the end of the case. Make sure to properly label syringes, and make sure during a handoff you go over what was given, what needs to be dosed, and any unique concentrations of medications you might have drawn up. Consider using a handoff checklist.

 

Dennis Spence, PhD, CRNA


The views expressed in this article are those of the author and do not reflect official policy or position of the Department of the Navy, the Department of Defense, the Uniformed Services University of the Health Sciences, or the United States Government.


© Copyright 2016 Anesthesia Abstracts · Volume 10 Number 1, January 30, 2016




Regional Anesthesia
A smartphone-based decision support tool improves test performance concerning application of the guidelines for managing regional anesthesia in the patient receiving antithrombotic or thrombolytic therapy

Anesthesiology 2016; 124:186-98

McEvoy MD, Hand WR, Stiegler MP, DiLorenzo AN, Ehrenfeld JM, Moran KR, Lekowski R, Nunnally ME, Manning EL, Shi Y, Shotwell MS, Gupta RK, Corey JM, Schell RM


Abstract

 

Purpose The purpose of this study was to determine if using a smartphone-based decision support tool (smartphone group) would improve anesthesia providers’ scores on a test of the American Society of Regional Anesthesia (ASRA) consensus statement on regional anesthesia in patients receiving antithrombotic or thrombolytic therapy.

 

Background Adherence to evidence-based guidelines, such as those published by ASRA, is sometimes poor. One reason for this is that the ASRA consensus statement on regional anesthesia in the patient receiving antithrombotic or thrombolytic therapy is 40 pages long. Therefore, some anesthesia providers may not be familiar with the entire guideline. This could lead to poor adherence. Previous research suggests the use of cognitive aids in the form of smartphone-based decision support may improve guideline adherence.

 

Methodology This was a prospective, multicenter, randomized controlled trial. Participants at 8 academic centers were randomized to either an smartphone group or control group. Participant included:

  • anesthesia interns
  • anesthesia residents
  • anesthesia fellows
  • anesthesia faculty
  • regional anesthesia faculty

Participants completed a 20-question multiple-choice test involving clinical scenarios related to the ASRA guidelines. The test was developed using the Delphi Technique by anesthesiologists, educators, guideline experts, and faculty with experience in writing medical board questions. Each multiple-choice question was mapped to a specific portion of the ASRA guideline, and each question was written so that individual questions only tested a unique medication-action combination.

 

The smartphone-based decision support tool used was ASRA Coags, developed by investigators at Vanderbilt University, Department of Anesthesiology (see availability note at end). The ASRA Coags app is simple and easy to use. The app is based on the ASRA consensus statement on regional anesthesia in the patient receiving antithrombotic or thrombolytic therapy. It covers a range of medications and its decision support software covers the following four principal actions performed in regional and neuraxial anesthesia:

  1. Performing the regional or neuraxial procedure
  2. Restarting a medication after the procedure
  3. Removing a neuraxial/perineural catheter while an anticoagulant is being administered
  4. Restarting an anticoagulant medication after neuraxial/perineural catheter removal

 

Each participant had no prior experience with the smartphone-based decision support prior to the study. Participants in the control group could use any resource other than the smartphone-based decision support to complete the test. There was no time limit to complete the test. Statistical analysis was appropriate.

 

Result There were 122 in the smartphone group and 137 in the control group. Approximately two-thirds of participants were residents and the other third faculty. Participants in the smartphone group scored significantly higher on the test compared to the control group (92% ± 7% vs. 68% ± 16%, P < 0.001; Figure 1). Experience level (resident vs. faculty), age, or medication type (common vs. uncommon) did not impact overall scores between the two groups.

 

Only 63% of participants in the control group used a cognitive aid. Types of cognitive aids used by control group participants included:

  • ASRA website (31%)
  • other website (24%)
  • smartphone app (4%)
  • pocket card (18%)
  • ASRA publication (10%)
  • other (2%)

Participants in the control group who used some sort of cognitive aid performed significantly better than control subjects who did not (76% ± 15% vs. 57% ± 18%, P < 0.001; Figure 1). Of note, less than 10% in the control group referred to the full ASRA guideline when they took the test. 

 

Figure 1. Comparison of Test Scores

Figure 2

Note: Participants in the smartphone group scored significantly higher than those in the control group (P < 0.001). Subgroup analysis of the control group revealed those who used a cognitive aid performed significantly better than those who did not (P < 0.001).

*eDST = Electronic Decision Support Tool (Smartphone Group).

 

Conclusion The use of the ASRA Coags electronic decision support smartphone app improved participants’ scores on a test of the ASRA guidelines. These results highlight the importance of using smartphone-based decision support to guide decision making with regards to regional anesthesia in patients taking antithrombotic or antifibrinolytic agents.

 

Comment

I must admit I am a techie. I think development of the smartphone, specifically the iPhone, is one of the greatest inventions of the 21st century. I love the ability to quickly use an app to help me make a clinical decision. For example, I have purchased apps that help with ACLS, PALS, pediatrics, and preoperative evaluation decision making. I used to keep a copy of the ASRA guidelines on my smartphone, but it was cumbersome to refer to. Last year I came across the ASRA Coags app and have started using it regularly. These smartphone-based decision support apps are great cognitive aids and resources for anesthesia providers!

 

I am not surprised that participants in the smartphone group performed much better than those in the control group. They did even better than those in the control group who used some sort of cognitive aid. When I examined the actual questions and used the ASRA Coags app, I got nearly every question correct, just as those in the smartphone group did. Whether or not use of the ASRA Coags smartphone-based decision support equates to correct decisions and reduced complications in actual clinical practice remains to be seen. However, my own personal experience suggests that they would help.

 

Dennis Spence, PhD, CRNA


ASRA Coags is available for iOS on the iTunes App store ($3.99) and for Android on the Google Play store ($3.99).

 

Other smartphone apps (iPhone) you might want to check out include: ASRA LAST, Preop Eval, Pedi Safe, Pedi Stat, Gas Guide, Nerve Whiz, Block GuRU, ACLS Advisor, and PALS Advisor. I have no financial interests in any of these apps.

 

The views expressed in this article are those of the author and do not reflect official policy or position of the Department of the Navy, the Department of Defense, the Uniformed Services University of the Health Sciences, or the United States Government.

 


© Copyright 2016 Anesthesia Abstracts · Volume 10 Number 1, January 30, 2016