Search Journal-type in search term and press enter
Social Media-Follow Southwest Journal of Pulmonary and Critical Care on Facebook and Twitter

 Critical Care

Last 50 Critical Care Postings

(Click on title to be directed to posting, most recent listed first, CME offerings in Bold)

June 2018 Critical Care Case of the Month
Fatal Consequences of Synergistic Anticoagulation
May 2018 Critical Care Case of the Month
Airway Registry and Training Curriculum Improve Intubation Outcomes in 
   the Intensive Care Unit
April 2018 Critical Care Case of the Month
Increased Incidence of Eosinophilia in Severe H1N1 Pneumonia during 2015
   Influenza Season
March 2018 Critical Care Case of the Month
Ultrasound for Critical Care Physicians: Ghost in the Machine
February 2018 Critical Care Case of the Month
January 2018 Critical Care Case of the Month
December 2017 Critical Care Case of the Month
November 2017 Critical Care Case of the Month
A New Interventional Bronchoscopy Technique for the Treatment of
   Bronchopleural Fistula
ACE Inhibitor Related Angioedema: A Case Report and Brief Review
Tumor Lysis Syndrome from a Solitary Nonseminomatous Germ Cell Tumor
October 2017 Critical Care Case of the Month
September 2017 Critical Care Case of the Month
August 2017 Critical Care Case of the Month
Telemedicine Using Stationary Hard-Wire Audiovisual Equipment or Robotic 
   Systems in Critical Care: A Brief Review
Carotid Cavernous Fistula: A Case Study and Review
July 2017 Critical Care Case of the Month
High-Sensitivity Troponin I and the Risk of Flow Limiting Coronary Artery 
   Disease in Non-ST Elevation Acute Coronary Syndrome (NSTE-ACS)
June 2017 Critical Care Case of the Month
Clinical Performance of an Interactive Clinical Decision Support System for 
   Assessment of Plasma Lactate in Hospitalized Patients with Organ
   Dysfunction
May 2017 Critical Care Case of the Month
Management of Life Threatening Post-Partum Hemorrhage with HBOC-201 
   in a Jehovah’s Witness
Tracheal Stoma Necrosis: A Case Report
April 2017 Critical Care Case of the Month
March 2017 Critical Care Case of the Month
Ultrasound for Critical Care Physicians: Unchain My Heart
February 2017 Critical Care Case of the Month
January 2017 Critical Care Case of the Month
December 2016 Critical Care Case of the Month
Ultrasound for Critical Care Physicians: A Pericardial Effusion of Uncertain 
   Significance
Corticosteroids and Influenza A associated Acute Respiratory Distress 
   Syndrome
November 2016 Critical Care Case of the Month
October 2016 Critical Care Case of the Month
September 2016 Critical Care Case of the Month
Ultrasound for Critical Care Physicians: Unraveling a Rapid Drop of 
   Hematocrit
Fluid Resuscitation for Septic Shock – A 50-Year Perspective:
   From Dogma to Skepticism
August 2016 Critical Care Case of the Month
Ultrasound for Critical Care Physicians: Complication of a Distant
   Malignancy
July 2016 Critical Care Case of the Month
Ultrasound for Critical Care Physicians: Now My Heart Is Still 
   Somewhat Full
June 2016 Critical Care Case of the Month
May 2016 Critical Care Case of the Month
Design of an Electronic Medical Record (EMR)-Based Clinical Decision
   Support System to Alert Clinicians to the Onset of Severe Sepsis
April 2016 Critical Care Case of the Month
Ultrasound for Critical Care Physicians: Two’s a Crowd
March 2016 Critical Care Case of the Month

 

For complete critical care listings click here.

The Southwest Journal of Pulmonary and Critical Care publishes articles directed to those who treat patients in the ICU, CCU and SICU including chest physicians, surgeons, pediatricians, pharmacists/pharmacologists, anesthesiologists, critical care nurses, and other healthcare professionals. Manuscripts may be either basic or clinical original investigations or review articles. Potential authors of review articles are encouraged to contact the editors before submission, however, unsolicited review articles will be considered.

------------------------------------------------------------------------------------

Saturday
Jun022018

June 2018 Critical Care Case of the Month

Stephanie Fountain, MD

Banner University Medical Center Phoenix

Phoenix, AZ USA

 

Critical Care Case of the Month CME Information

Completion of an evaluation form is required to receive credit and a link is provided on the last panel of the activity. 

0.25 AMA PRA Category 1 Credit(s)™

Estimated time to complete this activity: 0.25 hours 

Lead Author(s): Stephanie Fountain, MD.  All Faculty, CME Planning Committee Members, and the CME Office Reviewers have disclosed that they do not have any relevant financial relationships with commercial interests that would constitute a conflict of interest concerning this CME activity.

Learning Objectives: As a result of completing this activity, participants will be better able to:

  1. Interpret and identify clinical practices supported by the highest quality available evidence.
  2. Establish the optimal evaluation leading to a correct diagnosis for patients with pulmonary, critical care and sleep disorders.
  3. Translate the most current clinical information into the delivery of high quality care for patients.
  4. Integrate new treatment options for patients with pulmonary, critical care and sleep related disorders.

Learning Format: Case-based, interactive online course, including mandatory assessment questions (number of questions varies by case). Please also read the Technical Requirements.

CME Sponsor: University of Arizona College of Medicine

Current Approval Period: January 1, 2017-December 31, 2018

Financial Support Received: None

 

History of Present Illness

A 60-year-old native American man presented to an outside hospital with several days of nausea, vomiting and diarrhea. The patient felt weak and called emergency medical services and was taken to the emergency department.

Past Medical History

He has a history of end stage renal disease secondary to diabetes mellitus and hypertension. He received a cadaveric renal transplant in 2008 which was complicated with acute on chronic rejection and symptomatic hyponatremia.

Physical Examination

His pulse was recorded as 28 beats/min and his blood pressure was 90/60.

Which of the following should be done? (Click on the correct answer to be directed to the second of six pages)

  1. Administer atropine
  2. Begin transcutaneous pacing
  3. Obtain a drug history
  4. 1 and 3
  5. All of the above 

Cite as: Fountain S. June 2018 critical care case of the month. Southwest J Pulm Crit Care. 2018;16(6):304-10. doi: http://doi.org/10.13175/swjpcc065-18 PDF 

Thursday
May312018

Fatal Consequences of Synergistic Anticoagulation

Payal Sen, MD1

Uddalak Majumdar, MD2

Patrick Rendon, MD1

Ali Imran Saeed, MD1

Akshay Sood, MD1

Michel Boivin, MD1

 

1University of New Mexico

Albuquerque, NM US

2Cleveland Clinic Foundation

Cleveland, OH USA

 

Abstract

Objective: Novel oral anticoagulants (NOACs) are increasingly being preferred by clinicians (and patients) because they have a wide therapeutic window and therefore do not require monitoring of anticoagulant effect. Herein, we describe the unfortunate case of a patient who had fatal consequences as a result of switching from warfarin to rivaroxaban.

Case Summary: A 90-year-old Caucasian woman, with atrial fibrillation on chronic anticoagulation with warfarin, was admitted to the hospital for pneumonia. She was treated with levofloxacin. In the same admission, her warfarin was switched to rivaroxaban. On Day 3 after the switch, her INR was found to be 6, and she developed a cervical epidural hematoma from C2 to C7. She ultimately developed respiratory arrest, was put on comfort care and died.

Discussion: Rivaroxaban and warfarin are known to have a synergistic anticoagulant effect, usually seen shortly after switching. Antibiotics also increase the effects of warfarin by the inhibition of metabolizing isoenzymes. It is hypothesized that these two effects led to the fatal cervical spinal hematoma. 

Conclusion: The convenience of a wide therapeutic window and no requirement of laboratory monitoring makes the NOACs a desirable option for anticoagulation. However, there is lack of data and recommendations on how to transition patients from Warfarin to NOACs or even how to transition from one NOAC to another. Care should be taken to ensure continuous monitoring of anticoagulation when stopping, interrupting or switching between NOACS to avoid the possibility of fatal bleeding and strokes.

Introduction

Novel oral anticoagulants (NOACs) are increasingly being preferred by clinicians (and patients) because they have a wide therapeutic window and therefore do not require monitoring of anticoagulant effect. They have also shown greater efficacy and safety when compared to warfarin (1). The choice among the novel oral anticoagulants depends on their different pharmacokinetic profile, patients' stroke and bleeding risk, comorbidities, drug tolerability and costs and, finally, patients' preferences (2). There is however, paucity of evidence regarding the process of switching from warfarin to a NOAC, from one NOAC to the other, and the consequent ‘synergism’ (3). Herein, we describe the unfortunate case of a patient who had fatal consequences as a result of switching from warfarin to rivaroxaban. We also wish to highlight the adverse effects that antibiotic interaction can have with both warfarin and the NOACS (4).

Case Report

A 90-year-old Caucasian woman, who resided in a nursing home was admitted to the hospital with chief complaints of fever and confusion for 2 days. She also had intermittent cough, but denied headache, blurry vision, dysuria, diarrhea and constipation. Past medical history was significant for non-valvular atrial fibrillation, for which she was on therapeutic anticoagulation with warfarin. Family history and social history were not significant. Vitals revealed a temperature of 100 F and physical exam was positive for crackles in the right lower lobe of the lung. Her white count was elevated at 16 x 103/µL, and hepatic and renal function were both normal. Chest x-ray revealed a right sided lower lobe pneumonia. She was admitted to the hospital for acute metabolic encephalopathy due to sepsis secondary to hospital associated pneumonia and was initially given a dose of vancomycin and piperacillin tazobactam, which was later narrowed to levofloxacin. 

Hospital Course

On day 2, the patient’s disorientation had improved marginally and her white count had also reduced to 11. Her INR was therapeutic on warfarin and she underwent transesophageal echocardiography and cardioversion for symptomatic atrial fibrillation with rapid ventricular rate. After a long discussion with the patient and her family, it was decided to switch from warfarin to rivaroxaban, to avoid the hassle of frequent INR monitoring. 

On Day 3, the patient suddenly developed tachypnea, hypotension and dysarthria after receiving the second dose of rivaroxaban. Rapid Response had to be called. Vitals revealed blood pressure of 92/52, respiratory rate 20, and heart rate of 84 with pulse oximetry showing 92% on 2 liters nasal cannula. 

Neurological Examination

Cognition was relatively normal. Patient was alert and oriented X 3.

Motor exam: The patient was quadriplegic.

Touch, pain, and pressure sensations were absent (0/4) below C3-C4.

Reflexes were diminished (¼) and she had absolutely no feeling of any noxious stimuli. Babinsky' s sign was negative.

Urgent Labs on Day 3 (current day)

Arterial blood gases: PaO2 of 62 on 3 liters oxygen via Nasal cannula, PaCO2 of 78.  

International Normalized Ratio (INR): 6, prothrombin time was 64.2 seconds.

Radiographic Imaging

Figure 1. Computed tomography scan of the neck revealed posterior cervical epidural hematoma (arrow) from C2 to C7 with cord compression.

 

Figure 2. Posterior epidural hematoma (arrow) extending from C2-3 through approximately C6-7, which caused significant spinal stenosis.

The patient was then rushed to the neurosurgical ICU. Neurosurgery was consulted and recommended reversing the anticoagulation and taking the patient for emergency surgical evacuation of the hematoma. However, on further discussion with the family, it was revealed that the patient’s earlier wishes had been to never be bedbound and paralyzed. Since she was a 90-year-old patient, chronically debilitated, with a do not resuscitate code status, the ultimate decision was to place her on comfort care. Patient passed away 24 hours later.

Discussion

Rivaroxaban and warfarin are known to have a synergistic anticoagulant effect, usually seen shortly after switching (5). Antibiotics also increase the effects of warfarin by the inhibition of metabolizing isoenzymes (4). It is hypothesized that these two effects led to the fatal cervical spinal hematoma. 

For decades, vitamin K antagonists like warfarin have been the agent of choice for oral anticoagulation in different clinical conditions. However, the disadvantages of warfarin are that it needs frequent INR monitoring, has a narrow therapeutic window and interacts with multiple food substances and drugs (6). Warfarin is also known to cause major bleeding. The NOACS (novel oral anticoagulants) such as the direct thrombin inhibitor dabigatran, and Factor Xa Inhibitors like rivaroxaban, edoxaban and apixaban have been developed almost fifty years after the approval of warfarin (7). These NOACS have more predictable pharmacodynamics and pharmacokinetics, fewer drug and dietary interactions and have the added advantage of not requiring frequent laboratory monitoring (7,8).  Clinicians are increasingly using these NOACS to replace Vitamin K antagonists for multiple indications like the prevention of thromboembolic complications in atrial fibrillation, treatment of Deep vein thrombosis (DVT) and pulmonary embolism (PE), and thromboprophylaxis during orthopedic surgery (9).

Rivaroxaban, which is an oxazolidinone derivative, inhibits both free Factor Xa and Factor Xa bound in the prothrombinase complex (10). It is a highly selective Factor Xa inhibitor and has high oral bioavailability, with rapid onset of action and a predictable pharmacokinetic profile across a wide spectrum of patients with respect to gender, age, weight and race (11).  There is paucity of data on how to safely switch from warfarin to rivaroxaban. Expert opinion is to switch 24 hours after INR < 3 (3). There is only one observational matched-cohort study of switching from warfarin to rivaroxaban and results supported present practices (3). It analyzed a French registry and fluindidione (not warfarin) was the Vitamin K Antagonist in about 90% of the study subjects. In another study of in silico effects, a post-switch synergistic anticoagulant effect has also been observed and a nomogram has been developed for switching to Rivaroxaban, based on INR for Caucasian and Japanese patients (5). INR is affected variably by rivaroxaban and cannot be used as a marker for its anticoagulant effect (12). Laboratory monitoring of anticoagulant effect of NOACs needs to be considered, since INR is unsuitable for this (13). 

Some of the manufacturers offer guidance relating to switching from warfarin to NOACs:

  • To apixaban: warfarin should be discontinued and apixaban started when the INR is <2.0.
  • To dabigatran: warfarin should be discontinued and dabigatran started when the INR is <2.0.
  • To rivaroxaban: warfarin should be discontinued and rivaroxaban started when the INR is <3.0.

With longer experience with these NOACs in Europe, the European Heart Rhythm Association does make slightly different recommendations than those in the United States (14). Again, looking at switching from a vitamin K antagonist to a NOAC, the group suggests:

  • The NOAC can be immediately initiated once the INR is <2.0.
  • If the INR is 2.0 to 2.5, the NOAC can be started immediately or (preferably) the next day.
  • If the INR is >2.5, use agent pharmacokinetics to estimate the time for the next INR.

As for moving from parenteral anticoagulation to a NOAC, the European recommendation is:

  • For unfractionated heparin (UFH), start the NOAC once the UHF is discontinued.
  • For low-molecular weight heparin (LMWH), start the NOAC when the next dose of LMWH would have been due.

Hence, switching vitamin K antagonists to newer direct oral anticoagulants (NOACs) is becoming routine now, since the latter are thought to have a reduced incidence of intracranial bleeding (15). This case teaches us that the synergistic effect and interactions with antibiotics should be kept in mind during switching and when possible, nomograms should be used. Further study is required regarding bridging doses, bridging periods and population-specific dosing. 

Conclusion

The convenience of a wide therapeutic window and no requirement of laboratory monitoring makes the NOACs a desirable option for anticoagulation. However, there is lack of data and recommendations on how to transition patients from a vitamin K antagonist to NOACs or even how to transition from one NOAC to another. Care should be taken to ensure continuous monitoring of anticoagulation when stopping, interrupting or switching between NOACS to avoid the possibility of fatal bleeding and strokes. Further trials are also needed to test for appropriate laboratory monitoring of the NOACs. Also, caution must be used whilst using antibiotics with the NOACs, since their interaction can often increase the efficacy of the NOACs and lead to fatal bleeding, like in our patient.

References

  1. Prisco D, Cenci C, Silvestri E, Ciucciarelli L, Di Minno G. Novel oral anticoagulants in atrial fibrillation: which novel oral anticoagulant for which patient? J Cardiovasc Med (Hagerstown). 2015 Jul;16(7):512-9. [CrossRef] [PubMed]
  2. Gallego P, Roldan V, Lip GY. Novel oral anticoagulants in cardiovascular disease. J Cardiovasc Pharmacol Ther. 2014 Jan;19(1):34-44. [CrossRef] [PubMed]
  3. Bouillon K, Bertrand M, Maura G, Blotiere PO, Ricordeau P, Zureik M. Risk of bleeding and arterial thromboembolism in patients with non-valvular atrial fibrillation either maintained on a vitamin K antagonist or switched to a non-vitamin K-antagonist oral anticoagulant: a retrospective, matched-cohort study. Lancet Haematol. 2015 Apr;2(4):e150-9. [CrossRef] [PubMed]
  4. Lane MA, Zeringue A, McDonald JR. Serious bleeding events due to warfarin and antibiotic coprescription in a cohort of veterans. Am J Med. 2014 Jul;127(7):657-663.e2. [CrossRef] [PubMed]
  5. Burghaus R, Coboeken K, Gaub T, Niederalt C, Sensse A, Siegmund HU, Weiss W, Mueck W, Tanigawa T, Lippert J. Computational investigation of potential dosing schedules for a switch of medication from warfarin to rivaroxaban-an oral, direct Factor Xa inhibitor. Front Physiol. 2014 Nov 7;5:417. [CrossRef] [PubMed]
  6. Ezekowitz MD, Aikens TH, Brown A, Ellis Z. The evolving field of stroke prevention in patients with atrial fibrillation. Stroke. 2010 Oct;41(10 Suppl):S17-20. [CrossRef] [PubMed]
  7. Mendell J, Zahir H, Matsushima N, Noveck R, Lee F, Chen S, Zhang G, Shi M. Drug-drug interaction studies of cardiovascular drugs involving P-glycoprotein, an efflux transporter, on the pharmacokinetics of edoxaban, an oral factor Xa inhibitor. Am J Cardiovasc Drugs. 2013 Oct;13(5):331-42. [CrossRef] [PubMed]
  8. Ogata K, Mendell-Harary J, Tachibana M, Masumoto H, Oguma T, Kojima M, Kunitada S. Clinical safety, tolerability, pharmacokinetics, and pharmacodynamics of the novel factor Xa inhibitor edoxaban in healthy volunteers. J Clin Pharmacol. 2010 Jul;50(7):743-53. [CrossRef] [PubMed]
  9. Bauer KA. Recent progress in anticoagulant therapy: oral direct inhibitors of thrombin and factor Xa. J Thromb Haemost. 2011 Jul;9 Suppl 1:12-9. [CrossRef] [PubMed]
  10. Roehrig S, Straub A, Pohlmann J, Lampe T, Pernerstorfer J, Schlemmer KH, Reinemer P, Perzborn E. Discovery of the novel antithrombotic agent 5-chloro-N-({(5S)-2-oxo-3- [4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5yl}methyl)thiophene- 2-carboxamide (BAY 59-7939): an oral, direct factor Xa inhibitor. J Med Chem. 2005 Sep 22;48(19):5900-8. [CrossRef] [PubMed]
  11. Eriksson BI, Borris LC, Dahl OE, Haas S, Huisman MV, Kakkar AK, Muehlhofer E, Dierig C, Misselwitz F, Kälebo P; ODIXa-HIP Study Investigators. A once-daily, oral, direct Factor Xa inhibitor, rivaroxaban (BAY 59-7939), for thromboprophylaxis after total hip replacement. Circulation. 2006 Nov 28;114(22):2374-81. [CrossRef] [PubMed]
  12. Favaloro EJ, Lippi G. The new oral anticoagulants and the future of haemostasis laboratory testing. Biochem Med (Zagreb). 2012;22(3):329-41. [CrossRef] [PubMed]
  13. Lindahl TL, Baghaei F, Blixter IF, Gustafsson KM, Stigendal L, Sten-Linder M, Strandberg K, Hillarp A; Expert Group on Coagulation of the External Quality Assurance in Laboratory Medicine in Sweden. Effects of the oral, direct thrombin inhibitor dabigatran on five common coagulation assays. Thromb Haemost. 2011 Feb;105(2):371-8. [CrossRef] [PubMed]
  14. Heidbuchel H, Verhamme P, Alings M, Antz M, Hacke W, Oldgren J, Sinnaeve P, Camm AJ, Kirchhof P; European Heart Rhythm Association. European Heart Rhythm Association Practical Guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation. Europace. 2013 May;15(5):625-51. [CrossRef] [PubMed]
  15. Caldeira D, Barra M, Pinto FJ, Ferreira JJ, Costa J. Intracranial hemorrhage risk with the new oral anticoagulants: a systematic review and meta-analysis. J Neurol. 2015 Mar;262(3):516-22. [CrossRef] [PubMed]

Cite as: Sen P, Majumdar U, Rendon P, Saeed AI, Sood A, Boivin M. Fatal consequences of synergistic anticoagulation. Southwest J Pulm Crit Care. 2018;16(5):289-95. doi: https://doi.org/10.13175/swjpcc058-18 PDF 

Wednesday
May022018

May 2018 Critical Care Case of the Month

Lacey Gagnon APRN, CNP
Theo Loftsgard APRN, CNP

Department of Anesthesiology and Critical Care

Mayo Clinic Minnesota

Rochester, MN USA

 

Critical Care Case of the Month CME Information

Completion of an evaluation form is required to receive credit and a link is provided on the last panel of the activity. 

0.25 AMA PRA Category 1 Credit(s)™

Estimated time to complete this activity: 0.25 hours 

Lead Author(s): Lacey Gagnon, APRN, CNP.  All Faculty, CME Planning Committee Members, and the CME Office Reviewers have disclosed that they do not have any relevant financial relationships with commercial interests that would constitute a conflict of interest concerning this CME activity.

Learning Objectives: As a result of completing this activity, participants will be better able to:

  1. Interpret and identify clinical practices supported by the highest quality available evidence.
  2. Establish the optimal evaluation leading to a correct diagnosis for patients with pulmonary, critical care and sleep disorders.
  3. Translate the most current clinical information into the delivery of high quality care for patients.
  4. Integrate new treatment options for patients with pulmonary, critical care and sleep related disorders.

Learning Format: Case-based, interactive online course, including mandatory assessment questions (number of questions varies by case). Please also read the Technical Requirements.

CME Sponsor: University of Arizona College of Medicine

Current Approval Period: January 1, 2017-December 31, 2018

Financial Support Received: None

 

Chief Complaint

Shortness of breath

History of Present Illness

The patient is a 44-year-old woman who was admitted with a history of “pericarditis”. She has a several years history of progressive shortness of breath, abdominal distention and lower extremity edema.

Past Medical History, Social History and Family History

She has a history of obesity, poorly controlled type 2 diabetes, uterine fibroids and hypertension. She does not smoke but does have 1-2 alcoholic beverages per day. Family history is noncontributory.

Physical Examination

  • Vital signs: pulse 96 beats/min, blood pressure 110/85 mm Hg, temperature 37° C, respirations 18 breaths/min.
  • Neck: there is jugular venous distention with a positive hepatojugular reflux.
  • Lungs: rales at both bases.
  • Heart: regular rhythm without murmur.
  • Abdomen: Distended. Shifting dullness is present.
  • Extremities: 2-3 pretibial pitting edema.

Chest Radiography

Chest x-ray shows a small right pleural effusion with mild vascular congestion at the bases. Heart size is normal.

Which of the following should be performed?

  1. Abdominal CT scan
  2. Echocardiography
  3. Thoracic CT scan
  4. 1 and 3
  5. All of the above

Cite as: Gagnon L, Loftsgard T. May 2018 critical care case of the month. Southwest J Pulm Crit Care. 2018;16(5):245-51. doi: https://doi.org/10.13175/swjpcc048-18 PDF 

Monday
Apr092018

Airway Registry and Training Curriculum Improve Intubation Outcomes in the Intensive Care Unit

Joshua Malo MD1

Cameron Hypes MD2

Bhupinder Natt MBBS1

Elaine Cristan MD1

Jeremy Greenberg MD1

Katelin Morrissette MD1

Linda Snyder MD1

James Knepler MD1

John Sakles MD2

Kenneth Knox MD1

Jarrod Mosier MD2

1 Department of Medicine, University of Arizona College of Medicine, Tucson, AZ

2 Department of Emergency Medicine, University of Arizona College of Medicine, Tucson, AZ

 

Abstract

Background: Intubation in critically ill patients remains a highly morbid procedure, and the optimal approach is unclear. We sought to improve the safety of intubation by implementing a simulation curriculum and monitoring performance with an airway registry. 

Methods and Methods: This is a prospective, single-center observational study of all intubations performed by the medical intensive care unit (ICU) team over a five-year period. All fellows take part in a simulation curriculum to improve airway management performance and minimize complications. An airway registry form is completed immediately after each intubation to capture relevant patient, operator, and procedural data.  

Results: Over a five-year period, the medical ICU team performed 1411 intubations. From Year 1 to Year 5, there were significant increases in first-attempt success (72.6 vs. 88.0%, p<0.001), use of video laryngoscopy (72.3 vs. 93.5%, p<0.001), and use of neuromuscular blocking agents (73.5 vs. 88.4%, p<0.001). There were concurrent decreases in rates of desaturation (25.6 vs. 17.1%, p=0.01) and esophageal intubations (5 vs. 1%, p=0.009). Low rates of hypotension (8.3%) and cardiac arrest (0.6%) were also observed.

Conclusions: The safety of intubation in critically ill patients can be markedly improved through joint implementation of an airway registry and simulation curriculum.

Introduction

Airway management is one of the highest risk procedures that can be performed in the intensive care unit (ICU). Despite technologic advances in methods for performing intubation, recent studies continue to report frequent adverse events associated with tracheal intubation, and complications occur in up to 40% of procedures (1-3). Even in the absence of anatomic predictors of a difficult airway, critically ill patients are particularly vulnerable to desaturation, hemodynamic instability, and cardiac arrest due to poor physiologic reserve (4, 5). Repeated or prolonged intubation attempts exhaust any physiologic reserve these patients may have, leading to more frequent adverse outcomes (6). Thus, maximizing first attempt success without an adverse event is the goal for airway management in this high-risk population (7, 8).

Much of the clinical practice regarding airway management in the ICU has been extrapolated from studies performed during elective intubations in the operating room (4). In recent years, there has been a greater focus on management strategies and outcomes in critically ill patients in the emergency department (ED) and ICU (3, 9, 10). In 2012, we initiated a comprehensive airway management quality improvement program to measure variables related to airway management in the ICU and identify targeted opportunities for intervention to improve outcomes (11). We first established a prospectively collected registry of all intubations performed in the medical ICU. After evaluation of the first year of data, a simulation-based curriculum for the pulmonary and critical care fellows was developed with a focus on identifying high-risk features, minimizing adverse events, and maximizing first-attempt success. Lastly, research questions were evaluated periodically to identify targeted opportunities for improvement. This paper will describe the outcomes after the first 5 years of our program.

Materials and Methods

This is a prospective single-center observational study of all intubations performed in the medical ICU from January 1, 2012 to December 31, 2016. The study has been granted an exemption from full review and is approved by the University of Arizona Institutional Review Board. The primary outcome of interest was first attempt success, while secondary outcomes included adverse events, drug and device selection, and method of preoxygenation.

This study took place at a large academic medical center with 20+ bed medical ICU. A medical ICU team consisting of an attending intensivist, a pulmonary/critical care or emergency medicine/critical care fellow, and internal medicine, emergency medicine, and occasionally family medicine residents assumes primary management of all patients admitted to the medical ICU service. All patients admitted to the ICU undergoing airway management by the medical ICU team were included in the study.

We have maintained a continuous quality improvement (CQI) database for all episodes of airway management performed by our medical intensive care teams since January 1, 2012. After each intubation, the operators record data pertinent to the procedure, including difficult airway characteristics, drug and device selection, and number of attempts, using a standardized form. The study primary investigator crosschecked a report generated by the electronic health record against the database to ensure forms were completed for all intubations. Forms were reviewed for completeness and internal consistency. Inconsistent or absent data were resolved by interview of the operator. The variables captured in the form have been previously described (11) and are adjusted occasionally to evaluate new variables of interest.

Our Pulmonary and Critical Care Medicine (PCCM) and Critical Care Medicine (CCM) fellowship programs implemented an 11-month, simulation-based airway management curriculum beginning on July 1, 2013. The curriculum is designed to improve situational awareness in the peri-intubation period as well as to emphasize techniques that will optimize chances of first-attempt success while minimizing complications. The general outline for the simulations has been previously described in detail (11). Briefly, the curriculum involves clinical scenarios of varying and generally progressive complexity, each of which is meant to emphasize certain aspects of airway management. As trainees progress, the curriculum emphasizes the identification and mitigation of factors that may decrease the likelihood of first-attempt success and increase the likelihood of complications. The annual fellowship complement includes 14 Pulmonary and Critical Care Medicine fellows and 2 Critical Care Medicine fellows. All fellows participate in the curriculum, which is updated to include recent advances in airway management from the literature and analysis of our own airway registry. A debriefing session following each simulation is used to emphasize specific learning points for the approach to airway management.

Statistical Analysis

Descriptive statistics were calculated for measured variables as means and standard deviations, medians and interquartile ranges (IQR), or proportions as appropriate. Categorical variables were compared using Fisher’s exact test. Comparisons between Year 1 and Year 5 were performed using the Two-Sample Test of Proportions. Categorical variables with multiple groups, such as preoxygenation, Operator PGY, and Device were evaluated with the test for trend using the likelihood ratio test. All statistical analyses were performed with Stata Version 14 (StataCorp, College Station, TX).

Results

During the 60-month study period, there were 1411 intubations performed. The patient and operator characteristics are shown in Table 1 and Table 2, respectively.

Table 1. Patient characteristics.

aSome DACs added over time. Limited mouth opening and secretions added after the first 8 months of data collection.

Table 2. First Operator Characteristics.

During the course of the study, there was no significant change in patient age or gender, the presence of difficult airway characteristics, starting saturation, or percentage of patients intubated after failing noninvasive positive pressure ventilation (NIPPV). There was a trend for decreased intubations resulting from failed extubation. The overall characteristics of intubation attempts are described in Table 3.

Table 3. Intubation characteristics.

There was a significant increase in the number of intubations performed by PCCM operators after the first year of the study (Year 1-5 difference +19%, p<0.001) accompanied by a decrease in intubations performed by internal medicine (Year 1-5 difference -9%, p=0.006) and emergency medicine residents (Year 1-5 difference -10%, p=0.003). Likewise, there was an increase in intubations performed by PGY 4 (Year 1-5 difference +13%, p=0.002) and PGY 6 (Year 1-5 difference +11%, p<0.001) operators with a concurrent decrease in those performed by PGY 2 (Year 1-5 difference -16%, p<0.001) and PGY 3 (Year 1-5 difference -8%, p=0.004) operators.

First-attempt success (FAS) occurred in 80.7% of intubations performed during the study period. The FAS rate increased linearly throughout the study period, with FAS of 72.6% in the first year and 88.0 % in the final year when looking at all operators (p<0.001) (Table 4, Figure 1, next page). 

There was a significant increase in the number of intubations performed by PCCM operators after the first year of the study (Year 1-5 difference +19%, p<0.001) accompanied by a decrease in intubations performed by internal medicine (Year 1-5 difference -9%, p=0.006) and emergency medicine residents (Year 1-5 difference -10%, p=0.003). Likewise, there was an increase in intubations performed by PGY 4 (Year 1-5 difference +13%, p=0.002) and PGY 6 (Year 1-5 difference +11%, p<0.001) operators with a concurrent decrease in those performed by PGY 2 (Year 1-5 difference -16%, p<0.001) and PGY 3 (Year 1-5 difference -8%, p=0.004) operators.

First-attempt success (FAS) occurred in 80.7% of intubations performed during the study period. The FAS rate increased linearly throughout the study period, with FAS of 72.6% in the first year and 88.0 % in the final year when looking at all operators (p<0.001) (Table 4, Figure 1).

Table 4. Outcomes.

 

Figure 1. First-attempt success and complications over time.

For patients intubated by fellows only, FAS increased from 77% to 92% over the 5-year period (p<0.001).

During the entire study period, at least one complication occurred in 28.7% of intubations. The incidence of complications decreased throughout the first 48 months but increased slightly in the final 12 months of the study, driven primarily by an increase in hypotension (Table 4, Figure 2).

Figure 2. Neuromuscular blocking agent (NMBA) use, video laryngoscopy (VL) use, and occurrence of esophageal intubations, desaturation, and hypotension over time.

There was a decrease in the rate of desaturation from the first year to the final year of the study (25.6% to 17.1%, p=0.01). Esophageal intubations also decreased significantly over this time (5% to 1%, p=0.009). Hypotension and cardiac arrest occurred in 8.3% and 0.6% of intubations, respectively, during the entire study period.

There was a trend towards decreased use of midazolam and propofol throughout the study period while the use of etomidate tended to increase, although these changes were not significant (Table 3). A neuromuscular blocking agent (NMBA) was used in 77.4% of intubations during the study period, increasing from the first year to the final year (73.5% to 88.4%, p<0.001), driven primarily by an increase in the use of rocuronium.

There was a significant transition from the use of direct laryngoscopy (DL) to video laryngoscopy (VL) over the course of the study (p<0.001). DL was chosen as the first approach in 22.0% of intubations in the first year and only 2.9% in the final year. Conversely, the use any form of VL on the first attempt increased from 72.3% of intubations in the first year to 93.5% in the final year. Flexible fiber optic intubation was used infrequently during the entire study period, being the first device used in 4.3% of intubations.

Various methods of preoxygenation were used throughout the study period with some form of preoxygenation occurring in 97.5% of intubations. From the first year to the final year of the study, the use of bag-valve-mask (BVM) ventilation tended to decrease (30% to 12.2%) with a concurrent trend in increasing use of NIPPV for preoxygenation (19.4% to 29.7%).

Discussion

Our experience demonstrates that utilization of a comprehensive approach to airway management including an ongoing simulation-based training curriculum and CQI database is associated with an improved first-attempt success rate for the intubation of critically ill patients. This was accompanied by changes in approach to airway management, with increased use of VL and NMBA on the first attempt, as well as an increased proportion of airways being managed by more experienced operators.

While some of the observed improvement in FAS may be attributed to more experienced operators managing the airway on the first attempt, the sharp increase in fellow-level operators after implementation of the curriculum may point to increased fellow confidence or increased recognition of high-risk patients. Furthermore, as adjunctive strategies such as ramp positioning (12-14) and apneic oxygenation (15, 16) have become increasingly recognized as potentially beneficial, a continuous training curriculum provides opportunities for evaluating trainees’ knowledge of these techniques and reinforcing their incorporation into airway management.

We have previously reported on the impact of a simulation-based curriculum on operator confidence, first-attempt success, and procedural complications (11). The combination of this curriculum with a CQI database has a marked effect on the approach to management of these patients. Strategies presented and employed in the curriculum have been informed by previous reports from our database. For example, after demonstrating improved first-attempt success with the use of neuromuscular blockade (17) and video laryngoscopy (18), the didactic portion of our curriculum incorporated these findings, which were rapidly used with increasing frequency in our intensive care unit. The integration of the curriculum and CQI database facilitates adoption of best practices, leading to a significant improvement of first-attempt success rate over a relatively short time span. The continued improvement over the course of five years is likely due to the incorporation of the practices above during this time.

Tools traditionally used for predicting difficulty of airway management have focused primarily on characteristics of an anatomically difficult intubation (19, 20). More recently, there has been an expanded focus on physiologic characteristics that may lead to complications and decreased success of intubation. However, currently available instruments for ICU patients, such as the MACOCHA score, continue to put heavy emphasis on anatomic factors and are not validated for the use of VL (21). We have found difficult airway characteristics associated with decreased FAS in the setting of VL and have focused efforts at minimizing their impact (22). In our population, we noted a consistent improvement in Cormack-Lehane grade and percentage of glottic opening (POGO) score, despite a high prevalence of anatomic difficult airway characteristics. We have also noted a significant decrease in desaturations, esophageal intubations, and a trend towards decreased overall complications. In comparison to other studies of intubation complications in critically ill patients, we found generally lower rates of esophageal intubation (1, 2, 6) and similar (10) or lower rates of desaturation (1, 2) (Table 5).

Table 5. Incidence of complications in the published literature.

Our rate of hypotension is fairly low relative to several other studies (2, 10, 23) despite a fairly inclusive definition (administration of fluid or phenylephrine bolus, initiation or increase of vasopressor infusion). Moreover, cardiac arrest was extremely uncommon in our population, occurring in 0.57% of intubations.

Data regarding optimal approach have been controversial, and randomized trial results do not always coincide with observational studies. Although randomized controlled trials have called into question the benefit of VL (24-27), there are several important limitations to each of these studies to consider when interpreting the comparison between DL and VL. In some, patients were excluded either directly (25) or indirectly (24, 26) for a history of a difficult intubation or anticipated difficult intubation. The use of endotracheal tubes without a stylet may have also influenced outcomes (27).

Our experience is a pragmatic example of the effect of device selection on first attempt success in that we have >1400 patients, operators with varying experience, and have no patients excluded because of potential difficulty. Thus, while randomized trials may be ideal, they are costly and time-consuming and may delay identification and implementation of best practices. The FAS rate in our cohort in its first year was similar to that observed in several of these trials but improved substantially over the 5-year period. One reason for the improved FAS in our study may be the continuous simulation-based training with a focus on video laryngoscopy as the first technique of choice for the majority of airways. In comparison to other widely cited studies of airway management in critically ill patients (1, 21), our cohort demonstrated a very low incidence of difficult airways, only 2% in the final year, despite a similar presence of difficult airway characteristics. This may be an effect of the training program suggesting that perhaps airway training with a global view of airway management focusing on increasing FAS and reducing complications is even more important than equipment considerations.

Our study has several limitations. The single-center, observational nature of this study makes it at risk of bias despite attempts to identify and control for factors that may influence the results. Data forms were completed by the operator, introducing potential for reporting bias, although attempts to minimize this were made by intermittent correlation with the medical record. Although FAS is an accepted outcome for studies evaluating intubation strategies, data regarding mortality or late morbidity were not captured. The increase in hemodynamic complications in the final year is of interest, but data regarding this complication and its consequences were limited and should be a focus of future research. Despite these limitations, the consistent improvement in FAS and low incidence of difficult airways in the final year of the study warrant serious consideration of these findings.

Conclusion

We have found that a comprehensive strategy employing a simulation-based curriculum and continuous quality improvement database was associated with significant improvements in first-attempt success at intubation in critically ill patients throughout the 5-year study period. We suggest that wider adoption of this practice could vastly improve the safety of intubation in this high-risk patient population.

References

  1. Griesdale DE, Bosma TL, Kurth T, Isac G, Chittock DR. Complications of endotracheal intubation in the critically ill. Intensive Care Med. 2008;34(10):1835-42. [CrossRef] [PubMed]
  2. Jaber S, Amraoui J, Lefrant JY, Arich C, Cohendy R, Landreau L, et al. Clinical practice and risk factors for immediate complications of endotracheal intubation in the intensive care unit: a prospective, multiple-center study. Crit Care Med. 2006;34(9):2355-61. [CrossRef] [PubMed]
  3. Lapinsky SE. Endotracheal intubation in the ICU. Crit Care. 2015;19:258. [CrossRef] [PubMed]
  4. Mort TC. The incidence and risk factors for cardiac arrest during emergency tracheal intubation: a justification for incorporating the ASA Guidelines in the remote location. J Clin Anesth. 2004;16(7):508-16. [CrossRef] [PubMed]
  5. Mosier JM, Joshi R, Hypes C, Pacheco G, Valenzuela T, Sakles JC. The Physiologically Difficult Airway. West J Emerg Med. 2015;16(7):1109-17. [CrossRef] [PubMed]
  6. Mort TC. Emergency tracheal intubation: complications associated with repeated laryngoscopic attempts. Anesth Analg. 2004;99(2):607-13, table of contents.  [CrossRef] [PubMed]
  7. Hypes C, Sakles J, Joshi R, Greenberg J, Natt B, Malo J, et al. Failure to achieve first attempt success at intubation using video laryngoscopy is associated with increased complications. Intern Emerg Med. 2017 Dec;12(8):1235-43. [CrossRef] [PubMed]
  8. Park L, Zeng I, Brainard A. Systematic review and meta-analysis of first-pass success rates in emergency department intubation: Creating a benchmark for emergency airway care. Emerg Med Australas. 2017;29(1):40-7. [CrossRef] [PubMed]
  9. Simpson GD, Ross MJ, McKeown DW, Ray DC. Tracheal intubation in the critically ill: a multi-centre national study of practice and complications. Br J Anaesth. 2012;108(5):792-9. [CrossRef] [PubMed]
  10. Smischney NJ, Seisa MO, Heise KJ, Busack KD, Loftsgard TO, Schroeder DR, et al. Practice of Intubation of the Critically Ill at Mayo Clinic. J Intensive Care Med. 2017:885066617691495. [CrossRef] [PubMed]
  11. Mosier JM, Malo J, Sakles JC, Hypes CD, Natt B, Snyder L, et al. The impact of a comprehensive airway management training program for pulmonary and critical care medicine fellows. A three-year experience. Ann Am Thorac Soc. 2015;12(4):539-48. [CrossRef] [PubMed]
  12. Khandelwal N, Khorsand S, Mitchell SH, Joffe AM. Head-Elevated Patient Positioning Decreases Complications of Emergent Tracheal Intubation in the Ward and Intensive Care Unit. Anesth Analg. 2016;122(4):1101-7. [CrossRef] [PubMed]
  13. Ramkumar V, Umesh G, Philip FA. Preoxygenation with 20 masculine head-up tilt provides longer duration of non-hypoxic apnea than conventional preoxygenation in non-obese healthy adults. J Anesth. 2011;25(2):189-94. [CrossRef] [PubMed]
  14. Turner JS, Ellender TJ, Okonkwo ER, Stepsis TM, Stevens AC, Sembroski EG, et al. Feasibility of upright patient positioning and intubation success rates at two academic emergency departments. Am J Emerg Med. 2017. [CrossRef] [PubMed]
  15. Mosier JM, Hypes CD, Sakles JC. Understanding preoxygenation and apneic oxygenation during intubation in the critically ill. Intensive Care Med. 2017;43(2):226-8. [CrossRef] [PubMed]
  16. Sakles JC, Mosier JM, Patanwala AE, Arcaris B, Dicken JM. First Pass Success Without Hypoxemia Is Increased With the Use of Apneic Oxygenation During Rapid Sequence Intubation in the Emergency Department. Acad Emerg Med. 2016;23(6):703-10. [CrossRef] [PubMed]
  17. Mosier JM, Sakles JC, Stolz U, Hypes CD, Chopra H, Malo J, et al. Neuromuscular blockade improves first-attempt success for intubation in the intensive care unit. A propensity matched analysis. Ann Am Thorac Soc. 2015;12(5):734-41. [CrossRef] [PubMed]
  18. Hypes CD, Stolz U, Sakles JC, Joshi RR, Natt B, Malo J, et al. Video Laryngoscopy Improves Odds of first-attempt success at intubation in the intensive care unit. A propensity-matched analysis. Ann Am Thorac Soc. 2016;13(3):382-90. [CrossRef] [PubMed]
  19. Mallampati SR, Gatt SP, Gugino LD, Desai SP, Waraksa B, Freiberger D, et al. A clinical sign to predict difficult tracheal intubation: a prospective study. Can Anaesth Soc J. 1985;32(4):429-34. [CrossRef] [PubMed]
  20. Wilson ME, Spiegelhalter D, Robertson JA, Lesser P. Predicting difficult intubation. Br J Anaesth. 1988;61(2):211-6. [CrossRef] [PubMed]
  21. De Jong A, Molinari N, Terzi N, Mongardon N, Arnal JM, Guitton C, et al. Early identification of patients at risk for difficult intubation in the intensive care unit: development and validation of the MACOCHA score in a multicenter cohort study. Am J Respir Crit Care Med. 2013;187(8):832-9. [CrossRef] [PubMed]
  22. Joshi R, Hypes CD, Greenberg J, Snyder L, Malo J, Bloom JW, et al. Difficult airway characteristics associated with first-attempt failure at intubation using video laryngoscopy in the intensive care unit. Ann Am Thorac Soc. 2017;14(3):368-75. [CrossRef] [PubMed]
  23. Perbet S, De Jong A, Delmas J, Futier E, Pereira B, Jaber S, et al. Incidence of and risk factors for severe cardiovascular collapse after endotracheal intubation in the ICU: a multicenter observational study. Crit Care. 2015;19:257. [CrossRef] [PubMed]
  24. Driver BE, Prekker ME, Moore JC, Schick AL, Reardon RF, Miner JR. Direct versus video laryngoscopy using the c-mac for tracheal intubation in the emergency department, a randomized controlled trial. Acad Emerg Med. 2016;23(4):433-9. [CrossRef] [PubMed]
  25. Griesdale DE, Chau A, Isac G, Ayas N, Foster D, Irwin C, et al. Video-laryngoscopy versus direct laryngoscopy in critically ill patients: a pilot randomized trial. Can J Anaesth. 2012;59(11):1032-9. [CrossRef] [PubMed]
  26. Janz DR, Semler MW, Lentz RJ, Matthews DT, Assad TR, Norman BC, et al. Randomized trial of video laryngoscopy for endotracheal intubation of critically ill adults. Crit Care Med. 2016;44(11):1980-7. [CrossRef] [PubMed]
  27. Lascarrou JB, Boisrame-Helms J, Bailly A, Le Thuaut A, Kamel T, Mercier E, et al. Video laryngoscopy vs direct laryngoscopy on successful first-pass orotracheal intubation among ICU patients: A randomized clinical trial. JAMA. 2017;317(5):483-93. [CrossRef] [PubMed]

Cite as: Malo J, Hypes C, Natt B, Cristan E, Greenberg J, Morrissette K, Snyder L, Knepler J, Sakles J, Knox K, Mosier J. Airway registry and training curriculum improve intubation outcomes in the intensive care unit. Southwest J Pulm Crit Care. 2018;16(4):212-23. doi: https://doi.org/10.13175/swjpcc037-18 PDF 

Monday
Apr022018

April 2018 Critical Care Case of the Month

Clement U. Singarajah, MD

Phoenix VA Medical Center

Phoenix, AZ USA

 

History of Present Illness

A 70-year-old man was admitted for shortness of breath (SOB) secondary to a “COPD exacerbation/ILD”. A pulmonary consult was placed for possible interstitial lung disease (ILD). A thoracic CT scan for pulmonary embolism showed no embolism and no obvious ILD. He was treated for a COPD exacerbation with the usual therapy of antibiotics, steroids, nebulized bronchodilators and oxygen. He started to improve.

A few days later as he was preparing for discharge, the patient suddenly decompensated becoming more SOB (once more proving that this a dangerous time for patients in hospital). There were reports that this began after he choked and perhaps aspirated on some food and drink. His blood pressure remained stable, but he became tachycardic to 130 beats/min, hypoxic on 100% non-rebreathing mask with saturations of 92%. Obvious clinical acute respiratory failure was present. The patient was started on non-invasive ventilation but continued to deteriorate.  He was deemed too unstable to obtain a CT scan. EKG showed sinus tachycardia. The patient was transferred to the ICU for respiratory failure. A chest x-ray was obtained (Figure 1).

Figure 1. Panel A: Admission chest x-ray which was interpreted as not different from the patient’s previous chest x-ray. Panel B: Portable chest x-ray taken shortly after initiation of non-invasive ventilation just after arrival in the intensive care unit.

The portable chest x-ray taken in the ICU shows a new right-sided consolidation and which of the following? (Click on the correct answer to proceed to the second of six pages)

Cite as: Singarajah CU. April 2018 critical care case of the month. Southwest J Pulm Crit Care. 2018;16(4):183-91. doi: https://doi.org/10.13175/swjpcc042-18 PDF