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Clinical pearls of physical restraints

• Use the least amount of force possible when restraining any patient, but especially patients with increased ICP.
  • Sedatives should be considered.
• Law enforcement must be on board the ambulance during transports of arrested persons with handcuffs applied.

Clinical pearls of chemical restraints

• Advanced airway equipment and cardiac monitoring must be available if a patient is to be given chemical restraints.
• If a patient’s respiratory status declines, ALS providers must be able and willing to take over the airway to prevent hypoxia.

Prehospital medicine, by its very definition, occurs in an imperfect and potentially dangerous environment. While the vast majority of prehospital encounters occur without incident, some situations necessitate EMS providers gain rapid control of patient behavior to protect the safety of the public and the patient.

The decision to provide prehospital agitation management involves heavy consideration of the patient’s rights, clinical status and the necessity of prehospital intervention in the first place.

What is patient agitation, really?

Agitation is a catch-all term for any form of general uncooperative state or aggressive behavior by a patient. It is a broad spectrum and ranges from verbal aggression to physical violence.

Agitation is most likely to require specific management when the patient’s behavior has begun posing a threat to themself, the community at large or the EMS providers tasked with their care. Examples of moderate-to-severe agitation include physical strikes toward EMS providers, self-injurious behavior or repeated attempts to remove vital, life-sustaining equipment, such as an ETT post-arrest.

Causes of patient agitation

When addressing agitation, it is important to ask why the patient is agitated in the first place. Underlying medical issues are often the cause for a patient’s agitation. For instance, patients who are delirious secondary to sepsis are unlikely to benefit from heavy sedatives and pharmacological intervention; rather, reversing their underlying acidosis and hypoperfusion will be the most beneficial.

Alternatives to physical and chemical restraints

Verbal counselling and de-escalation are always the gold standard of agitation management. Verbal patient coaching must be tailored to the specific patient and scenario that EMS clinicians are dealing with. A 20-year-old male in college is likely to require different therapeutic communication measures than an 80-year-old woman who is upset EMS is removing her from her nursing home room.

When employing verbal counselling, remember the patient is an individual with their own reasons for being agitated. If you can reverse the reason for their agitation and address their concerns, they are likely to be more cooperative. We are never trying to be punitive with agitation management.

Physical restraints

Examples of restraint methods include cravats (triangular bandages) and commercial restraint devices. A rolled sheet can also be tied around the patient’s extremities as needed. Commercial restraint devices pose the least risk to the patient and are often the simplest to apply.

In addition, it is critically important to avoid restraining patients in the prone position. Patients in the prone position are at severe risk of positional asphyxia. A 2021 study found that patients restrained in the prone position have decreased cardiac output in addition to a significantly, dangerously reduced tidal volume [9]. Hogtying patients or bending the extremities backward is not an acceptable practice and risks harm to the patient.

Restraints are not without risk. Excessively tight restraints pose the risk of neurovascular compromise and damage. Perform full CMS (circulation, motor, sensory) checks of each extremity prior to and following application of restraints. Guidelines from 2021 allow for two finger breadths within each restraint to avoid compromising circulation [3]. The NAEMSP position paper on restraints recommends against the use of hard restraints, such as handcuffs [3].

Head injury victims are at increased risk for elevated intracranial pressure (ICP) concerns. The act of restraining them is likely to induce further agitation and confusion. In doing so, we risk elevating ICP further and exacerbating the issue. Use the least amount of force possible when restraining any patient, but especially patients with increased ICP.

Law enforcement interactions

It is never acceptable to sedate or restrain a patient solely based on law enforcement direction. Always perform your own comprehensive assessment of the patient’s status and weigh the benefits to the risks of sedation and restraint use.

A patient who is handcuffed and under arrest must have law enforcement physically on the ambulance. Law enforcement must be readily available to release the patient’s handcuffs if the patient’s status declines.

Chemical restraints

Advanced airway equipment and cardiac monitoring must be available if a patient is to be given chemical restraints. Many of the common agitation medications carry a significant risk of respiratory depression. If a patient’s respiratory status declines, ALS providers must be able and willing to take over the airway to prevent hypoxia.

End tidal CO2 monitoring (ETCO2) is especially important for monitoring sedated patients. ETCO2 capnography allows providers to see a real-time waveform of the patient’s respirations and assess their rate, quality and the presence of carbon dioxide retention. Sedated patients are at increased risk for hypoventilation, which will in turn induce carbon dioxide retention and potentially lead to respiratory acidosis. If this occurs, the patient may require ventilatory support.

Pulse oximetry is another important vital sign to assess but often has a delay when showing changes in patient status. It is also significantly less reliable for patients with darker skin complexions [1].

Video: Treating agitated patients

References

1. Al-Halawani, R., Charlton, P., Qassem, M., & Kyriacou, P. A. (2023). A review of the effect of skin pigmentation on pulse oximeter accuracy. Physiological Measurement, 44(5), 05TR01. https://doi.org/10.1088/1361-6579/acd51a

2. Golparvar, M., Saghaei, M., Sajedi, P., & Razavi, S. S. (2004). Paradoxical reaction following intravenous midazolam premedication in pediatric patients – a randomized placebo controlled trial of ketamine for rapid tranquilization. Paediatric Anaesthesia, 14(11), 924–930. https://doi.org/10.1111/j.1460-9592.2004.01349.x

3. Kupas, D. F., Wydro, G. C., Tan, D. K., Kamin, R., Harrell, A. J., & Wang, A. (2021). Clinical care and restraint of agitated or combative patients by emergency medical services practitioners. Prehospital Emergency Care, 25(5), 721–723. https://doi.org/10.1080/10903127.2021.1917736

4. Lingamchetty, T. N., Hosseini, S. A., & Saadabadi, A. (2023, June 5). Midazolam. StatPearls – NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK537321/

5. Olejarczyk, J. P., & Young, M. (2022, November 28). Patient rights and ethics. StatPearls NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/portal/utils/pageresolver.fcgi?recordid=660f5efd72b48f442b428a43

6. Rahman, S., & Marwaha, R. (2023, September 1). Haloperidol. StatPearls – NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK560892/

7. Rosenbaum, S. B., Gupta, V., Patel, P., & Palacios, J. L. (2024, January 30). Ketamine. StatPearls – NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK470357/

8. Sicari, V., & Zabbo, C. P. (2023, July 10). Diphenhydramine. StatPearls – NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK526010/

9. Steinberg, A. (2021). Prone restraint cardiac arrest: A comprehensive review of the scientific literature and an explanation of the physiology. Medicine, Science and the Law/Medicine, Science and the Law, 61(3), 215–226. https://doi.org/10.1177/0025802420988370

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How can we keep our patients and clinicians safe in the field, and maintain good working relationships with law enforcement?

The in-custody deaths of persons who had been administered ketamine for agitation have brought controversy and questions about the use of the drug in EMS. Supervisors and leadership are faced with having to make tough decisions about what to do when the roles of law enforcement and patient care collide. In some areas, politicians and leaders with little medical understanding have made decisions about the use of medications, instead of physicians and EMS leaders.

This is a problem that we must face head-on in EMS.

Ketamine is a medication that can provide rapid control of dangerously disruptive patients, allowing further assessment and treatment. It is a dissociative anesthetic that can be administered in a variety of ways, and at higher doses (4-5 mg/kg) will allow a violent, disruptive patient to be controlled to provide care.

Ketamine also is touted for having a wide safety profile, and there are cases where patients have been given large doses of it in error, with no documented ill effects.

However, the cases of Elijah McClain and others show that there is a risk to using ketamine as a chemical restraint, especially when the patient is in, or attempting to be brought into law enforcement custody. EMS agencies have come under fire in some areas for relying on ketamine to control patients, sometimes at the behest of law enforcement officers who may not understand the risks of using this drug fully.

The results can be devastating, and for the most part; avoidable.

How can we keep our patients and clinicians safe in the field, and maintain good working relationships with law enforcement?

Following are 6 strategies to avoid ketamine pitfalls and emphasize patient safety.

1. Engage law enforcement leadership.

As leaders, we have to be able to discuss with them the goals of assisting law enforcement safely for all. The paramount goal of EMS needs to be patient care, first and foremost. That needs to be communicated to police leadership.

Share what we can do for patients in police custody, and what you will not do, and develop plans to respond to agitated patients. At the least, any call where an agitated patient in police custody leads to EMS response, this warrants both EMS and police supervisors to respond to the scene, to coordinate and make sure lines do not get crossed. Open lines of communication will help to prevent decisions made ad hoc in the heat of the moment.

2. Put patient care first.

Educate your staff and first-line supervisors as to their role in these incidents. EMS needs to stay in their lane as caregivers, and not be police. We are there for the patient first. Their safety and health are our responsibility, and when we forget that in the heat of the moment; that is where the problems begin. We need to educate and develop the culture in our agencies that we are patient advocates, and that a patient’s custody status has no bearing on their treatment.

3. Teach CRM to help medics communicate in high-stress encounters.

Make crew resource management skills part of your training program so that clinicians can communicate effectively under stressful situations. Use the PACE format (Probe, Alert, Challenge, Emergency) to train paramedics and first-line supervisors how to talk in these situations.

4. Have policies

Develop strong policies in accordance with your medical director, and make sure they are based on current science.

5. Avoid flat dosages.

Every patient should receive a weight-based dose consistent with recommendations. This does not have to be calculated at the scene, you can incorporate a card or reference with patient weights, milligrams and volume that can lower cognitive load at a stressful time.

6. Monitor patients closely after administering ketamine.

Every patient who receives medication for sedation or restraint should at a minimum be regarded as a medical patient who requires monitoring and transport to a hospital ED for further care. The patient should be placed on a cardiac monitor, including pulse oximetry, and end-tidal carbon dioxide waveform capnography should be used without exception.

EtCO2 gives you a breath-by-breath measurement of how the patient is oxygenating, and ventilating, and will alert you to a problem with the patient well before the pulse oximeter or ECG will. Once we’ve given a drug, we can’t take it back; and our responsibility is now that patient’s overall safety.

These ideas are only a start, but hopefully, by engaging law enforcement leadership, developing policies and culture, and placing the patient first and foremost; we can minimize the risk and do better for the people we serve.

This article, originally published on August 02, 2022, has been updated.

Share Your Capno Story With Us Do you have a story about how capnography made a difference? Share your story with us and we may publish it on CapnoAcademy.

After seeing Dr. Joelle Donofrio-Odmann’s talk in Prodigy EMS’ free Refresh program, I knew Medic Mindset listeners needed to hear from her. She is an associate professor of pediatrics and emergency medicine and an EMS associate medical director in San Diego.

In this episode of The Thinking Series, she shares her passion and expertise on the topic of pediatric respiratory distress. She covers how she uses the pediatric assessment triangle to stratify patients and how she thinks about the diseases of the upper and lower airways (and the ones that don’t fit neatly in either).

Other topics include epinephrine in anaphylaxis, ketamine in asthma, and bulb syringes for clearing secretions causing airway obstructions. Listeners also get to hear a cameo visit from Dr. Peter Antevy from the “In the Zone. The Antevy Zone” episode.

Share Your Capno Story With Us Do you have a story about how capnography made a difference? Share your story with us and we may publish it on CapnoAcademy.

By Sean Hulsman

Reported cases of anaphylaxis are on the rise according to the CDC. This is particularly worrisome for EMS because pediatric patients suffering anaphylaxis often present differently than adults and pose special problems for prehospital clinicians. Read Pediatric Anaphylaxis: How Capnography can help assessment and treatment and take this quiz to test your knowledge.

About the Author:

Sean Hulsman, MEd, EMT-P is Director of Education at Twin City Ambulance Corporation in Western New York. He began his EMS career in 1992 and continues to teach and work in the field. You can contact Sean via his blog: Coarse Asystole.

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Cardiogenic oscillations (COS) of the capnography waveform match the patient’s heart rate and are caused by pulmonary artery pulsations

Your team intubated a 38-year-old woman who was found unresponsive following a poly-substance drug overdose. Intubation was performed without difficulty and no medications were necessary. Waveform capnography confirmed correct placement of the 9.0 endotracheal tube.

You are in the process of tweaking ventilator settings when you observe the abrupt onset of rapid oscillations in the capnography waveform:

The patient does not appear to be awakening, seizing or in any distress. Your patient monitor however, cannot seem to display a consistent end-tidal CO2 value. Instead, the displayed value seems to be changing moment to moment, varying between 18 and 47 mm Hg.

Additionally, the oscillations seem to be triggering frequent ventilator breaths above the assist control/volume control set rate. Thinking these oscillations may be related to “curare cleft” capnogram indentations associated with attempted spontaneous breaths in a mechanically ventilated patient, or potentially related to underlying seizure activity, you administer a hefty benzodiazepine dose without effect.

Cardiogenic oscillations

First described in the anesthesia literature in 1961, the rogue waveforms you have encountered are called cardiogenic oscillations (COS). Two important findings were noted in early studies: the oscillations match heart rate and their appearance is associated with decreased airway resistance.[1] In fact, if you were to superimpose the oscillations over the patient’s EKG, the rate of the oscillations will match the heart rate. This relationship led to a theory that cardiogenic oscillations resulted from cardiac pressure waves transmitted through the mediastinal anatomy to the airways. 

As clinicians increased reliance on capnography for ventilator changes and ventilators evolved to become more sensitive to patient efforts, COS, although rare, became more problematic. Sporadic COS led to lower or inaccurately reported ETCO2; providers sometimes misinterpreted COS for efforts at spontaneous breathing or rebreathing resulting in unnecessary drug administration or ventilator circuit manipulation; COS inappropriately triggers mechanical ventilator breaths in a variety of vent modes; and most recently, COS significantly interferes with capnography based cardiac output determinations.

In a search for optimal means of troubleshooting interference, researchers found it difficult to categorize patient populations or situations where COS were most likely to occur.  

Finally, in 2009, a group of cardiothoracic surgery researchers decided to trace the origin of COS. During cardiac surgery, the chest is open and both pulmonary and cardiac anatomy are completely accessible, so it did not take long for these researchers to discover the actual cause of COS was not cardiac pressure changes, but pulmonary artery pulsations.[2] A few years later, these data were confirmed and explained in more detailed animal studies.[3]

The right heart generates pulmonary blood flow in a pulsatile fashion that transmits a wave of pressure along the pulmonary vascular tree. In the absence of significant airflow resistance or with sensitive pressure or airflow monitoring devices, it is easy to see how pulsatile pulmonary artery blood flow could cause both airflow and pressure changes. Airflow fluctuations would be reflected in a capnogram; pressure fluctuations would be detected by pressure sensors in a ventilator circuit.

You may have noticed the reference to absence of airflow resistance as a precursor to COS. That finding led to what currently is the most practical and effective means of resolving COS: PEEP (Positive End Expiratory Pressure). Suggested in a case report published in 2000, the addition of PEEP to the ventilator circuit will generally resolve COS interferences with both capnography and ventilator breath triggering.[4]

In the opening case presentation, the addition of 5 CWP of PEEP to the ventilator circuit eliminated the rogue COS waveforms. In cases where PEEP has already been applied, slight upward adjustments may be necessary to reduce or eliminate COS artifact.

About the Author

Mike McEvoy, PhD, NRP, RN, CCRN is the EMS coordinator for Saratoga County, New York and a paramedic supervisor with Clifton Park & Halfmoon Ambulance. He is a nurse clinician in cardiothoracic surgical intensive care at Albany Medical Center where he also chairs the Resuscitation Committee and teaches critical care medicine. He is a lead author of the “Critical Care Transport” textbook and Informed Emergency & Critical Care guides published by Jones & Bartlett Learning. Mike is a frequent contributor to EMS1.com and a popular speaker at EMS, fire, and medical conferences worldwide. Contact Mike at [email protected].

References

1. Arieli A. Cardiogenic oscillations in expired gas: origin and mechanism.  Resp Physio. 1983;52: 191-204.

2. Tusmana G, Suarez-Sipmannb F, Peces-Barbac G, Climented C, Aretad M, Arenasb PG, Bohme SH.  Pulmonary blood flow generates cardiogenic oscillations.  Resp Phys & Neurobio.  2009; 167: 247–254.

3. Fernando Suarez-Sipmann F, Santos A, Peces-Barba G, Bohm SH, Gracia JL, Caldero´n P, Tusman G.  Pulmonary artery pulsatility is the main cause of cardiogenic oscillations.  J Clin Monit Comput.  2013; 27:47–53.

4. Marks R, Sidi A.  Elimination of cardiogenic oscillations in the capnograph by applying low positive end-expiratory pressure (PEEP).  J Clin Monit 2000;16: 177-181.

Share Your Capno Story With Us Do you have a story about how capnography made a difference? Share your story with us and we may publish it on CapnoAcademy.

By Sean Hulsman

Sepsis carries a greater mortality rate than many diseases we consider common place like breast cancer and AIDS. Surprisingly, EMS has only recently begun to broaden training on diagnosis and treatment of patients suffering from sepsis in the field. The physiology of sepsis is very much within the realm of understanding for EMS providers, and knowledge of ETCO2 with respect to how the body responds to systemic infection can help us better identify these patients when we encounter them. Read Use of capnography to identify sepsis and take the quiz to test your knowledge of sepsis and capnography.

About the author:

Sean Hulsman, MEd, EMT-P is Director of Education at Twin City Ambulance Corporation in Western New York. He began his EMS career in 1992 and continues to teach and work in the field. You can contact Sean via his blog: Coarse Asystole.

Share Your Capno Story With Us Do you have a story about how capnography made a difference? Share your story with us and we may publish it on CapnoAcademy.

Join us for an introduction to Sepsis and the role capnography plays in its recognition in the prehospital environment. Sepsis is a significant cause of death and may be more frequently seen by prehospital providers than previously thought.

About the webinar:

This webinar will review recognition of sepsis, prehospital interventions that may affect patient outcomes, and how capnography could be a valuable tool in sepsis and other shock states. Contemporary protocols and new directions in recognition and management of sepsis will also be explored.

What you’ll learn:

• How capnography can help a paramedic detect sepsis
• How sepsis presents in patients
• What paramedics can do to help prevent early mortality in patients
• An overview of current research on the subject

Mike McEvoy, PhD, NRP, RN, CCRN is the EMS Coordinator for Saratoga County, New York and a Paramedic Supervisor for Clifton Park & Halfmoon Ambulance. He is a nurse clinician in the cardiac surgery ICU at Albany Medical Center where he also teaches critical care medicine and chairs the hospital Resuscitation Committee.

Mike is the EMS editor for Fire Engineering magazine, chief medical officer and firefighter/paramedic for West Crescent Fire Department, and actively involved in fire, EMS and resuscitation research. He is an EMS Section board member for the International Association of Fire Chiefs and a lead author of the textbook “Critical Care Transport” and the “Informed” Pocket References (published by Jones & Bartlett). In his free time, Mike is an avid hiker and winter mountain climber.

For the Spanish Language version of this webinar, click here.

Share Your Capno Story With Us Do you have a story about how capnography made a difference? Share your story with us and we may publish it on CapnoAcademy.

CapnoAcademy is a free online resource dedicated to training EMS clinicians to help improve patient outcomes by using capnography monitoring in the pre-hospital environment. Powered by EMS1, CapnoAcademy includes best practices, field examples, and guides on how EMS clinicians can use capnography monitoring to help improve patient care and save lives.

Learn More

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