Importantly, such cases often involve death in young, previously healthy individuals, and these are very charged issues that often make the 6 o'clock news. With racial, social, and police brutality overtones and omnipresent litigation risks, the EP must be squeaky clean with regard to medical intervention and requisite charting issues.
Metabolic Acidosis in Restraint-Associated Cardiac Arrest: A Case Series
Hick JL, et al
Acad Emerg Med
This extremely informative article was one of the first to highlight this issue. It should be read by all EPs and probably promulgated to law enforcement and hospital security guards. Even ambulance personnel need to be enlightened. The authors present a series of five patients who were violently agitated, subsequently physically restrained, and in short order, developed cardiac arrest associated with a profound metabolic acidosis. This paper highlights the danger of restraint-associated acidosis and raises significant negative cardiovascular and respiratory issues that likely contribute to sudden and unexpected cardiovascular collapse. Although previous reviews have documented sudden death while restrained, acidosis has not been highlighted as a major confounding factor.
In all cases, the patients were in an ED and continued to struggle, despite maximum physical restraints. All were under the influence of cocaine, a drug like methamphetamine that is now almost normal flora under this scenario. As a result of the unfortunate experience with these index cases, the hospital changed its restrain-and-struggle approach to one of proactive medical management to avoid similar cases in the future.
In the first case, a 36-year-old man who was extremely agitated and belligerent while walking down the street was apprehended by police. It required several officers to subdue him, and while still fighting vigorously and lying prone with his hands tied behind him, he was transported to the ED. Soon after arrival in the ED, he had a cardiac and respiratory arrest. A pH of 6.46 was obtained five minutes after resuscitation. A pre-arrest pH was not available. Lactic acidosis was thought to be the cause of the impressive alteration in pH. The drug screen was positive for cocaine. This patient suffered rhabdomyolysis with transient renal insufficiency as well as elevated liver enzymes. With aggressive supportive care, he was discharged without significant sequelae in a few days. (This patient was one of the fortunate ones).
A 39-year-old man with an undiagnosed psychiatric illness was brought to the ED for evaluation of agitation and worsening psychosis. He was extremely violent, was restrained by several security guards, and placed in a prone position with his arms tied behind him. He soon became apneic and pulseless, and required resuscitation that included a thoracotomy. The pH obtained during the resuscitation was 6.81. Unfortunately, the man died two days later because of persistent hypoxic brain damage suffered during the cardiac arrest.
Three other cases presented a similar scenario. All were relatively young men who were using cocaine, were agitated, confused, and violent, and were restrained by prehospital and ED personnel. All had a significant metabolic acidosis, and all suffered cardiac arrest shortly after arrival to the ED. The lowest pH reported was an impressive 6.25. Three of the five patients did not survive cardiac arrest even though they were witnessed in the hospital. The authors note that the literature is replete with episodes of sudden cardiac arrest in individuals who experience extreme exertion or were fleeing police or fighting vigorously while being physically restrained. Most had used cocaine. Aside from the metabolic acidosis, no specific cause for the sudden cardiac arrest has been determined.
Lactic acidosis secondary to vigorous physical activity has been well documented, and a significant acidosis may develop in a matter of minutes. In the presence of the vasoconstriction produced by cocaine, such exercise-induced lactic acidosis is likely enhanced. Psychosis or drug-induced delirium will render anyone insensitive to pain, allowing individuals to exert themselves in a manner and extent that would have been previously impossible. The rise in catecholamine levels from this massive violent activity also may contribute to cardiac arrest.
The authors also comment on the previously used restraint policy of numerous police departments where patients are hogtied or hobbled, a position where the ankles and wrist are bound together behind the back. When placed in a prone position, this type of restraint further infuriates the individual. It has been theorized that a person's respirations while restrained are compromised. The true adverse clinical effect, however, has not been fully characterized. Struggling may decrease the ability to develop a compensatory respiratory alkalosis, further exacerbating any metabolic acidosis that consistently develops secondary to exertion.
The authors conclude that continued combativeness despite restraints, especially when patients are taking sympathomimetic medications, has potential for sudden death. They note that physical restraints often provoke even further struggling and the development of overwhelming and occasionally life-threatening metabolic acidosis precipitating a downward spiral. Prolonged violent struggling against restraints should be recognized as a true medical emergency and responded to in an appropriate manner by medical personnel. They suggest aggressive sedation and chemical restraint, and possible attempts to correct the metabolic derangement prior to cardiac arrest. As an example of the importance of recognizing this phenomena and altering practice, five additional patients who were struggling against restraints were reported. All patients were aggressively sedated and none experienced cardiac arrest, even though the pH was as low as 6.7 in one.
Comment: This paper was published in 1999, but many recognized the seriousness of the metabolic derangements from violent exertion in a restraint position long before then. Hopefully your local police department and EMS are similarly clued in to the counterproductive nature of prolonged efforts to physically restrain a violently agitated patient in lieu of chemical restraint. Prehospital personnel must, of course, do what is necessary to subdue the individual, get him to the hospital, and protect themselves, so some type of initial physical restraint is undoubtedly required under most circumstances. The message to get out to police and prehospital personnel is that they should bring the patient to the ED immediately, avoid prolonged incapacitating restraint, and not put the patient in any position that compromises breathing or circulation.
The actual contribution of positing on acidosis is likely minimal, and the exact pathophysiology is a complex issue that will be explored in detail next month. Suffice it to say that pre-restraint exertion, drug overdose, and continued exertion are likely more culpable than simply the restraint position.
A commonly used mechanical restraint for prehospital transport is hogtieing or the hobble restraint. The hands and feet are bound together, and the back is arched when the bound extremities are then tied together. This position in itself is not problematic for a short period of time, but with continued struggling, especially when the patient is face down (prone position), derangements in cardiopulmonary can ensue, the exact consequences of which are unknown. (Wien Klein Wochenschr 1997;109:359.)
For some reason, many physicians are still reluctant to aggressively sedate any patient who does not have a specific diagnosis. Presumably altering an already clouded or befuddled sensorium is thought to be counterproductive. I would vehemently argue just the opposite. I could never understand this approach, especially when a meaningful history, mental status evaluation, blood pressure, simple x-ray, and blood test are impossible to glean. I assume this reluctance is a throwback to the old days when there was a consensus that head-injured patients never received sedation because one could not follow the mental status. Of course with the advent of the CT scan, this dogma joined the brontosaurus. Head-injured patients, especially if they are agitated, are now routinely sedated/paralyzed so intracranial pressure is lessened and they can expeditiously receive imaging studies. No one ever operates on head trauma victims anymore solely because of mental status; such decisions are made on the results of CT scans and other clinical parameters. Likewise I just can't think of any clinical situation where a violently agitated and uncooperative patient is preferred to one that is calm, sleeping, or even paralyzed and on a ventilator. This includes those with sepsis, congestive heart failure, multiple trauma, and drug overdose.
I haven't met a paramedic yet who is willing to give aggressive intravenous sedation for a wildly agitated patient, but this is the obvious next step in prehospital care. We usually get a call that security is required for an uncontrollable patient, but I never had a request for an order of 40 mg of prehospital Valium under such circumstances. This may be because it is impossible to obtain a line, but I think it's more of a tradition than a problem with IV access. There are many potent sedatives that can be safely administered to patients who have a totally undifferentiated form of agitation or otherwise uncontrollable behavior, and this is fertile ground for research. Currently even IM medications such as Geodon or Zyprexa safely work wonders on such patients.
The obvious message for emergency personnel is that these patients are as much at risk for sudden cardiac arrest as are patients with elevated ST segments, diaphoresis, and crushing substernal chest pain. Acute uncontrollable violent behavior is a medical emergency that should be responded to in an appropriate emergency manner. Regardless of the diagnosis, no patient should be allowed to undergo prolonged excessive or violent activity while being only physically restrained. The metabolic acidosis, hyperthermia, and rhabdomyolysis that are sure to follow may precipitate cardiac arrest. If you are smart enough to look for them or able to get a blood sample, some of the lowest pHs in your career will be found in such patients.
One need not immediately differentiate psychiatric patients from those with head trauma or those under the influence of PCP, amphetamines, or the omnipresent cocaine. However, hypoglycemia should be an immediate rule-out. Such patients are totally out of control and simply can't be talked down or made to lie still while in handcuffs or restraints or while being smothered by the security staff. They don't feel pain, and even mace and a policeman's nightstick do not get them to behave. In fact, such attempts to subdue the patient may prompt further violent activity and only worsen the metabolic derangements. Future columns will discuss specific drugs and Taser interventions in detail.
The uninformed doctor or nurse stays out of the room and allows the police “to do their work,” waiting for the obnoxious and unruly individual to come to his senses so he can be treated in a leisurely manner. Such complacent doctors and nurses are frequently involved in a sudden cardiac arrest and futile resuscitation a few minutes later. It's only human nature and a well appreciated reflex to allow obnoxious patients to continue to be agitated. The patience of even the most cool, compassionate, or caring physician or nurse quickly wears thin under some circumstances. Faced with a plethora of “real” patients, it doesn't take long for an initial caring attitude to turn to hostility against the perpetrator. But when there are eight police/security guards in the room, it's time for the clinician to take charge. Let the testosterone level of others rise to the occasion; you have to keep a cooler head.
For those who think that they are teaching a patient manners or punishing him for rude behavior, I can assure you that the patient never remembers his bites, spits, swears, or punches. The smart physician will go into the room with a syringe full of his favorite rapidly acting sedative even before the patient is off the paramedic stretcher. The best axiom is: Get the police out of the room and the Ativan, Haldol, Geodon, Zyprexa, or ketamine into the patient as soon as possible. I can see no downside to aggressively sedating any wildly agitated patients from the onset. Whether it's simple hypoglycemia (always check this at the bedside), alcohol intoxication, or some type of bizarre seizure, the doctor must be involved and in control from the beginning. Future columns will discuss specific medical conditions that may produce the violent agitated state, and will focus on exactly how to obtain the much needed upper hand quickly and safely.
Sudden Death in Individuals in Hobble Restraints During Paramedic Transport
Stratton SJ, et al
Ann Emerg Med
This is one of many reports that document sudden death in patients undergoing hobble-type restraints while in the throws of violent or agitated clinical states. Both of the cases discussed in this report were young men who were under the influence of mind-altering drugs and were physically restrained by police by what was then a well accepted technique. Specifically, the patients had their hands cuffed behind their back, the ankles were bound, and then the wrist and ankles were bound together. Then the patients were transported in a prone position. This technique has been termed a hobble restraint.
In the first case, a 35-year-old man under the influence of amphetamines was hobble-restrained by police and then transported by paramedics to the ED for evaluation. The duration of struggling while restrained is not clear from the report, but the man developed asystole while being transported in the ambulance. Resuscitation was unsuccessful.
In the second case, a 30-year-old man was handcuffed by police for erratic behavior. The man reacted violently to minor restraints, and police subsequently put him in the hobble device. He was transported by ambulance in the prone position and continued to be combative. Within a few minutes of transport, the patient suffered a cardiac arrest, and resuscitation was unsuccessful. In both cases, the levels of cocaine or amphetamines were thought to be nonlethal, and there was no other reason than the restraining and violent activity to explain the cardiac arrest.
The authors stress that while patients have died under such circumstances during law enforcement transport, they believe this was the first case where patients actually died while being supervised by medical personnel in an ambulance. They note that the patients died and were not resuscitated even when trained medical personnel and ALS equipment were available for a witnessed cardiopulmonary arrest. The cause of death could not be determined with certainty, but the type of restraint and prone positioning is known to restrict the motion of the diaphragm and may lead to asphyxia.
Comment: The expert witness for the defense would opine that the drugs were the direct cause of death, and this is often the case. Chronic cocaine and methamphetamine use does cause a cardiomyopathy that can lead to lethal dysrhythmias. It is unclear whether these cases represent restraint asphyxia or drug overdose, but the rapidity of death and the unsuccessful resuscitation of a witnessed arrest should certainly get your attention. This report discusses the problem of positional asphyxia and sudden cardiac arrest, and is one of many such reports in relatively healthy individuals who are violently struggling against restraints. The actual harm of the position itself has been debated, however, and is likely not the sole culprit.
It is also alarming that these patients died while under the direct observation of ACLS personnel, probably signifying the effect of cocaine and methamphetamine and the massive nonreversible metabolic derangement. Previous reports have likewise documented that once cardiac arrest occurs, a successful resuscitation is not always a foregone conclusion, even if it occurs in the ED or under the direct observation of trained prehospital medical personnel. It's unclear exactly how long is required for restraint-induced cardiac arrest to occur, but apparently it is not a condition that takes more than a few minutes to develop. A short chase by police is enough to drop the perpetrator's pH to the low 7s. In August in Philadelphia, the core temperature can be well over 105°F on presentation. By the time the patient is in the ED, the cardiac arrest clock is already ticking, and the countdown is well underway.
Numerous authors have evaluated the pathophysiologic derangement of hobble restraints and excessive physical activity. A detailed discussion of positional asphyxia can be found in an article by Chan et al. (Ann Emerg Med 1997;30:578.) This study was a somewhat artificial situation that included only a four-minute exercise period in non-drugged volunteers, followed by a restrained position. The authors found that the restrained position did produce some restrictive pulmonary function, but did not clinically alter oxygen saturation or ventilation.
The exact pathophysiologic derangement produced by the restrained prone position is still somewhat elusive, but it's probably a bad position to be in. Prolonged hobble restraint during extreme exertion should probably be avoided (how long and how much exertion are unknown), and adding the prone position does not help. Meredith et al (Am J Forensic Med Pathol 2005;26:117) also have demonstrated that there is no significant effect on respiratory function by handcuffing behind the back during maximal exercise in healthy volunteers. Such restraint did not alter lactate or heart rate over similar exercise conditions in the unrestrained person. Again, none were drugged with cocaine or methamphetamine.
Considering the information available, restrained patients should probably be placed in a lateral or supine position rather than a prone position even if prehospital times are short. One would only hope that the multiple reports of sudden death in such patients have prompted police and rescue personnel to avoid the hogtied position in the first place, but that's not the entire issue to address. It is clear that hobble restraints do little to stop the violent struggling of drugged or psychotic patients. My experience is that the tighter the restraints, the greater the struggling. Although this technique may offer the best protection to rescue personnel, be the easiest way to transport patients, and not markedly increase the potential for harm, the EP should reverse this positioning as soon as safely possible.
CAVEATS ON SUDDEN DEATH IN VIOLENTLY AGITATED PATIENTS
* Cardiac arrest can occur precipitously and unexpectedly in young and previously healthy individuals who violently struggle against physical restraints.
* Once cardiac arrest ensues, even when witnessed and in the ED, resuscitation is often not successful.
* A marked metabolic acidosis is a common theme and possible precipitating event.
* The cause of death is multifactorial and not solely linked to positioning of the patient.
* Metabolic derangements can occur pre-restraint or be secondary to drug effect, but they can be exacerbated by continuing violent struggle against physical restraints.
* Hyperthermia and rhabdomyolysis are common findings after prolonged struggling while restrained.
* It is human nature to meet force with force on the combative patient and naive to expect patients to calm themselves once arrested or in the hospital.
* The traditional show of force, reasoning, or threats of various interventions do little under these circumstances, and are often counterproductive and waste time.
* Once safety issues are addressed, the clinician should take control of the situation rapidly with the aim of expeditiously calming the patient by any means necessary.
* Chemical restraint (sedation, even muscular paralysis) is often required and preferred to continual prolonged violent struggling in physical restraints.
* Patients do not remember their actions or behavior.
* Deaths under such circumstances are fraught with very charged issues, including police brutality and racial and social issues, and such cases often become headline news.
* The clinician should be very attentive to medical issues and litigation risks when there is potential for a bad outcome.
* The clinician should not be concerned about issues of battery, unlawful restraint, subsequent litigation, or unrealistic restraint laws when time is of the essence to control the patient or personnel in danger.
* The imperative is to provide the safest possible environment to medical personnel and the patient, a goal often difficult to achieve.
Reader Feedback: Readers are invited to ask specific questions and offer personal experiences, comments, or observations on InFocus topics. Literature references are appreciated. Pertinent responses will be published in a future issue. Please send comments to email@example.com. Dr. Roberts requests feedback on this month's column, especially personal experiences with successes, failures, and technique.
Dr. Roberts: I enjoyed your thorough discussion of the urinalysis, one of my favorite tests in the ED. (EMN 2007;29:24.) In your discussion on specific gravity, there is one situation in which a low specific gravity tends to accompany dehydration and clinical hypovolemia: the intoxicated patient. Because alcohol inhibits the production of anti-diuretic hormone, a urine with very low specific gravity is frequently seen, and as a result of this dilute urine (and perhaps other malnutrition issues we frequently see in the alcoholic), the intoxicated patient is clinically dry. In fact, in the appropriate clinical setting, a specific gravity of 1.003 is frequently a giveaway for some serious recent alcohol consumption. Thanks again for your super article. — Bruce Nisbet, MD, Newark, DE
Dr. Roberts responds: I agree with the ethanol issue, Dr. Nisbet; thanks for the addition. There are other conditions that also would produce a falsely low urine specific gravity in the presence of volume depletion. The inability of the kidney to concentrate urine in sickle cell disease readily comes to mind, and myriad other kidney diseases will impair renal concentrating ability. Nephrogenic diabetes insipidus will produce this picture, caused by various drugs, especially lithium.© 2007 Lippincott Williams & Wilkins, Inc.