To thoracotomy, or not to thoracotomy?
September 12th, 2011 by peter_lunny No comments »August 30, 2011 By Chris Nickson at Lifeinthefastlane.com and from Scott Weingart at EmCrit.org
A 26 year old man has been BIBA as a priority following a serious chest injury. The trauma team has been assembled and the patient is transferred onto the trauma table. You glance at the emergency thoracotomy tray and wonder if you’ll need to use it…
Questions:
Q1. What is the definition of ‘emergency thoracotomy’?
Definitions vary widely, but a useful definition of emergency thoracotomy is:
“a thoracotomy performed prehospital, in the emergency department or elsewhere that is an integral part of the initial resuscitation of a patient”
Q2. What are the contraindications to emergency thoracotomy in the seriously ill trauma patient?
The indications and contraindications for emergency thoracotomy are controversial, and may vary between institutions.
In general, the following are considered contraindications to performing an emergency thoracotomy:
prehospital CPR performed for >15 minutes after penetrating chest injury without response
prehospital CPR performed for >10 minutes after blunt chest injury without response
the presence of coexistent injuries that are unsurvivable, e.g. severe head trauma
(an exception maybe the patient who is a potential organ donor)
asystole is the presenting rhythm, and there is no pericardial tamponade
Furthermore, it makes little sense to perform an emergency thoractomy in settings where there is no hope of providing definitive surgical interventions following the procedure.
The Moore et al (2011) study, which collected data from 18 US trauma centers, suggests that emergency thoracotomy is not as hopeless as once believed — hence blunt trauma alone is not listed as a contraindication. Also, compared to the recommendations of Hunt et al (2005) — as featured in EMCrit Podcast 36: Traumatic Arrest — longer CPR times are allowed (10 and 15 minutes, rather than 5 and 10 minutes for blunt and penetrating trauma respectively). Even with these increased time allowances there are still a few reported cases of patients with both penetrating or blunt chest trauma who have survived following even longer periods of CPR.
Q3. When considering the indications for emergency thoracotomy, how is the physiological status of the patient classified?
Survival rates directly correlate with the patient’s physiological status. This physiological status needs to be taken into account when considering the indications for an emergency thoracotomy.
According to Lorenz et al (1992) the patient’s physiological status can be classified as follows:
I — no signs of life (see Q4)
II — pulseless electrical activity
III — profound shock: SBP<60 mmHg; transient / no response to fluid resuscitation.
IV — mild shock: SBP 60-90 mmHg; stable response to fluid resuscitation.
It becomes evident that your patient was stabbed in the left side of his chest. The paramedics reported signs of life at the scene.
Q4. In the context of severe chest trauma what are considered ‘signs of life’?
According to Hunt et al (2005) ‘signs of life’ include:
-presence of a pulse or spontaneous movements
-GCS>3
-presence of pupillary reflexes, corneal reflexes or gag reflexes
-evidence of cardiac electrical activity on ECG, or contractile activity on bedside ultrasound
(this information is rarely available in a prehospital setting)
The definition of what constitute ‘signs of life’ in this setting remains surprisingly controversial. As implied by the contraindications listed in
Q2, emergency thoracotomy is essentially futile unless the patient has, or recently had, some signs of life.
Q5. Should emergency thoracotomy be performed if he now has:
a) no signs of life?
Only if:
the patient had definite signs of life at the scene, and
none of the contraindications listed in Q2 are present.
b) pulseless electrical activity?
Only if there is evidence of:
intrathoracic hemorrhage
severe extrathoracic hemorrhage
pericardial tamponade
systemic air embolism
c) a systolic blood pressure <60 mmHg; transiently or non-responsive to fluid resuscitation?
Only if there is evidence of:
intrathoracic hemorrhage
severe extrathoracic hemorrhage
pericardial tamponade
systemic air embolism
The indications are the same as for scenario (b) above.
d) a systolic blood pressure between 60 and 90 mmHg; stable response to fluid resuscitation?
No
If possible, he should be urgently transferred to an operating theatre for an urgent thoracotomy instead.
Q6. What are the therapeutic measures that may be provided by emergency thoracotomy and what are their physiological rationales?
Emergency thoractomy allows the following therapeutic interventions to be performed:
-Release of pericardial tamponade —
-improves cardiac output and control of cardiac haemorrhage
-Control of intrathoracic vascular or cardiac haemorrhage —
-facilitates fluid resuscitation by ‘turning off the tap’
-improves cardiac output and myocardial perfusion
-Control of massive air embolism or bronchopleural fistula —
-resolves myocardial ischaemia and hence improves myocardial contractility as well as prevents neurological injury
-Open cardiac massage —
-improves resuscitative cardiac output and coronary perfusion especially with limited ventricular filling pressures
Occlusion of the descending aorta (cross-clamping) —
Redistribution of limited blood volume to myocardium and brain as well as limiting subdiaphragmatic losses.
Q7. Describe your approach to a patient who presents with blunt chest trauma who has signs of life on arrival in the ED, but then has a cardiac arrest.
Assess and manage the patient in a setting appropriately staffed and equipped for resuscitation using a coordinated team-based approach.
Perform the following key actions:
secure the airway by endotracheal intubation and commence ventilation and oxygenation.
seek and treat tension pneumothorax
e.g. bedside ultrasound and bilateral finger thoracostomies.
seek and treat pericardial tamponade
e.g. bedside ultrasound and emergency thoractomy.
If the patient has arrested and both tension pneumothorax and pericardial tamponade have been excluded, some experts would cease resuscitation at this point. Others would argue that there may be a role for emergency thoractomy if performed within 10 minutes of the arrest and the patient is actively resuscitated during this time.
Q8. How effective are closed chest cardiac compressions and resuscitation drugs such as adrenaline in the resuscitation of the arrested trauma patient?
Closed chest cardiac compressions and standard resuscitation drugs such as adrenaline are ineffective in the resuscitation of arrested trauma patients.
Despite this, CPR is routinely performed in such patients, especially in the prehospital setting. At best, CPR can be viewed as a temporising measure until emergency thoracotomy can be performed. It is far more important to give these patients blood products — not drugs — during resuscitation, while attempting to control the source of hemorrhage.
References
EMCrit Podcast 36 — Traumatic Arrest
[This case-based Q&A is largely based on this podcast by Scot Weingart]
Hunt PA, Greaves I, Owens WA. Emergency thoracotomy in thoracic trauma — a review. Injury. 2006 Jan;37(1):1-19. Epub 2005 Apr 20. Review. PMID: 16410079.
Life in the Fast Lane — ED Thoracotomy: Is It Just The First Part Of The Autopsy?
Lorenz HP, Steinmetz B, Lieberman J, Schecoter WP, Macho JR. Emergency thoracotomy: survival correlates with physiologic status. J Trauma. 1992 Jun;32(6):780-5; discussion 785-8. PMID: 1613839.
Moore EE, Knudson MM, Burlew CC, et al; WTA Study Group. Defining the limits of resuscitative emergency department thoracotomy: a contemporary Western Trauma Association perspective. J Trauma. 2011 Feb;70(2):334-9. PMID: 21307731.
Charcoal or not?
December 16th, 2010 by peter_lunny No comments »
By Dr. Bram Dolcourt
Recently I’ve gotten a few “Huh?” thrown my way when I tell people that…
I am actively discouraging the routine use of charcoal for acute overdoses.
The teaching has generally been to give charcoal in the face of an overdose. To many, what I’m saying is a bit surprising. Believe it or not, the American Academy of Clinical Toxicology recommends against routine charcoal use. I thought I’d write a few musings about how and why we recommend using it when we do.
The theory: Activated charcoal has a very high surface area. It will bind and hold a drug (xenobioic), preventing absorption. This will reduce the delivered dose to the patient and reduce toxicity.
Reality: There is very little evidence for the use of activated charcoal. It is occasionally useful and has potential for morbidity. Few patients who claim to have overdosed on a xenobiotic benefit from charcoal.
Who should get it?
For the undifferentiated intoxicated patient, charcoal should only be considered early in the ingestion. Generally, charcoal needs to make physical contact with the xenobiotic in order to absorb it. Once past the pylorus, the chance that charcoal will mix with the xenobiotic is fairly low. The stomach usually empties within 1 hour, although it may be as long as 2. Liquid preparations are absorbed too quickly for charcoal to have significant absorption.
Some xenobiotics may reduce GI motility and prolong the useful window for charcoal. A few authors recommend giving charcoal up to 4 hours post-ingestion. While there is no specific evidence, what is clear is that to have a beneficial effect, charcoal needs to be given early in the ingestion for a non-liquid preparation, generally within 1-2 hours and certainly not beyond 4 hours.
That time frame is for the general case. There are two other mechanisms of action that allow for alternate dosing for charcoal. First, some xenobiotics are reabsorbed and excreted into the bile (enterohepatic recirculation) or into the stomach (enterogastic recirculation). Charcoal can interrupt this recirculation and reduce the elimination half-life. Secondly, just as dialysis uses a membrane to separate substances from blood, the gut lumen can be used as a membrane to separate substances from blood. Amenable xenobiotics will cross from the blood, across the gut, into charcoal on the enteric side.
There is good evidence for using charcoal for 5 drugs: phenobarbital, carbamzepine, theophyllne, dapsone and qunine (quinidine). These are “Category A drugs.” For these xenobiotics the elimination half-life is reduced when charcoal is given. Multiple doses of charcoal can further increase the elimination rate for these drugs.
Multidose charcoal works for other xenobiotics, although the evidence is not as good (these are not called Category B drugs, BTW). Phenytoin, glipizide, aspirin (in high concentration), valproic acid, cyclosporine, amitriptyline, and colchicine are all potentially amenable to multidose charcoal.
How much should I give?
Several authors recommend giving 1 g per kg of charcoal, orally. Following this recommendation means that a child who ingests grams of a potentially lethal xenobiotic will receive less charcoal than an adult who eats a few milligrams of something moderately toxic. When placed in that context, it becomes clear the appropriate dose of charcoal should be in relation to the amount of the xenobiotic ingested, with the gram per kilogram being a ceiling dose.
Realistically, you want a 10:1 ratio, gram per gram, of charcoal to xenobiotic for optimal absorption. More is not helpful. Many patients only need a few mouthfuls of charcoal, as opposed to 50 or 100 grams. Consider a digoxin overdose; even for a massive ingestion of 100 tablets, one would likely only need to give 1.25 g of charcaol, which translates to about 6 ml. For a similar ingestion of amlodipine, one would only need to give approximately 50 ml of charcoal, or about 1/5 of the standard dose. It is very clear that we are giving most patients far too much charcoal.
For multidose charcoal, the dosage is less clear. Typically we recommend ½ gram per kg, up to 25 grams, ever 4 hours. This recommendation goes against what I said above. This is probably more than is necessary, however as the indications for multidose charcoal are quite different, we can get away with it.
Why wouldn’t I give charcoal?
All people aspirate to some degree, every day. Usually this isn’t a big deal as it is a small amount. However, in the face an altered mental status or vomiting, people aspirate more. A nasogastric tube also may worsen the risk, as the lower esophageal sphincter is held open. An endotracheal tube may reduce, but does not eliminate, aspiration. The sepsis literature is quite clear that intubated patients still aspirate and I can certain attest to suctioning charcoal out of the ET of many intubated patients.
Charcoal is mostly benign, however it may cause a pneumonitis when aspirated. The additional of sorbitol may worsen the pneumonitis. Charcoal comes in a significant volume; 50 grams of charcoal is usually in 240 ml of total volume. Rapidly instilling this volume can trigger vomiting due to stomach distention. While you want the charcoal to go in as early as possible, rapidly squirting it down an NG tube, can be counter productive and result in respiratory compromise.
A second and unusual complication may result from too much or two frequent multidose charcoal. In the setting of an ileus, multidose charcoal has resulted in charcoal bezoars. The charcoal was, effectively, compressed into briquettes, inside the gut lumen, resulting in obstruction.
The last complication comes from the sorbitol that is packaged with some charcoal. As there is little evidence for the benefits of using charcoal, there is even less for adding sorbitol (or any cathartic). The idea is that sorbitol increases transit time, removing the xenobiotic more quickly. Sorbitol also increases the total water content of the charcoal stool and may reduce the already small risk of a charcoal bezoar, but is of unproven benefit.
The issue comes about from inducing diarrhea and causing depletion in total body water and electrolytes. One of the ways a xenobiotic kills is by causing cardiovascular collapse. Inducing volume depletion, by osmotically drawing water into the gut, may worsen an already sick patient’s cardiovascular status. Electrolytes travel with water, resulting in an electolyte disturbance. Pediatric patient have developing severe metabolic disturbances from multiple doses of charcoal with sorbitol. Other decontamination strategies, such as urine alkalinization rely on a normal electrolyte profile, and charcoal with sorbitol may actually be counter-productive.
Tell me when I should use charcoal!
Like any drug, the astute clinician must weigh the risks and benefits of charcoal. First and foremost, a clinician needs to consider the lethality and potential morbidity associated with an overdose. Good supportive care has saved more lives than charcoal ever will. I may be so bold as to say that no one has every lived or died purely because of the prompt or lack of application of charcoal. What charcoal may do is moderate toxicity. For a non-lethal or unlikely to be lethal overdose, charcoal may not be needed. For a very lethal overdose, charcoal may reduce the toxicity so that very aggressive and attentive care could save the patient’s life.
Second, the clinician needs to examine the alternate therapies available. If there is a very good antidote or treatment available, charcoal is unlikely to add any benefits; the patient is going to fine either way.
Third, the clinician needs to consider how well the xenobiotic binds to charcoal. For any of the Category A drugs or the other listed medications, charcoal should be strongly considered as toxicity can be reasonably modulated. For metals, such as iron, or electrolytes, such as lithium, there is no potential benefit. For all others, the benefit is questionable.
Finally, patient factors need to be considered. A patient who is unconscious with a tenuous airway, there is a significant risk of charcoal aspiration; especially as an NG tube is needed. An aspiration and charcoal pneumonitis may be worse than the effects of the xenobiotic. Other patient factors to keep in mind: GI anatomy (bariatic surgery), age, co-operation (restraining and forcing down an NG tube on an agitated patient can be problematic), etc.
Can you give me some examples of what you would do?
Keep in mind that these are made up examples and may not encompass all issues, but here goes:
1) A young patient presenting 1-hour post ingestion of 10-20 tablets of extra strength acetaminophen.
This patient is a possible candidate for activated charcoal. The patient is presenting early and doesn’t have any obvious contraindications. This would be a 10 gram ingestion, thus using the 10:1 ratio, you would like to give 100 grams of charcoal, but probably can’t due to patient weight. The charcoal may prevent the patient from crossing the “possible toxicity” line on the Rumack-Matthew’s Nomogram, thus you may be able to prevent an admission. This ingestion is unlikely to be lethal and there is a very good antidote, so charcoal is probably not going to reduce morbidity or mortality.
2) A young patient with a large ingestion of carbamazepine. The patient is sleepy.
I would give this patient charcoal at any point during the ingestion and I would repeat doses every 4 hours. Carbamazepine is a Category A drug and very amenable to charcoal. It is also cardiotoxic, with significant risk for lethality. On the minus side, carbamazepine decreases mental status. The patient’s airway will need to be watched, but this patient will likely benefit from multidose activated charcoal.
3) A patient presents 1 hour after taking 10-20 risperidone tablets
This patient is not likely to benefit from charcoal and there is potential risk for harm. This is not likely to be lethal ingestion, and if it is, it will be from respiratory compromise or aspiration. Abnormal vitals and other derangements respond well to supportive care. Risperidone is a respiratory depressant, thus this patient may lose the airway with a full stomach, risking aspiration.
4) A patient who was found down after binging on diazepam and alcohol.
Charcoal is probably not indicated for this patient. This patient is not presenting early and will likely get very little, if any, benefit from charcoal. The patient has a decreased mental status with significant risk of vomiting and aspiration. As long as the patient is breathing, and the airway protected, s/he is at little risk of morbidity or mortality. Endotracheal intubation would likely be the optimal strategy for a patient presenting like this, who needs intervention.
Final thoughts…
Charcoal can be beneficial, but is not the end all treatment for the intoxicated patient. It should be given, not as a reflex, but after careful thought, articulating the expected benefit. The dose should be 10:1 ratio of charcoal to xenobiotic. Charcoal should be avoided when the ingested xenobiotic is not expected to cause morbidity or mortality after other care. The risk/benefit ratio of charcoal needs to be assessed in the context of patients with factors that may predispose to aspiration.
Dr Bram Dolcourt is an Assistant Professor in the Department of Emergency Medicine at Wayne State University in Detroit, MI. He completed a fellowship in Toxicology in 2009
Code Brown
May 22nd, 2010 by peter_lunny No comments »You have a 33 yo male with shortness of breath and palpitations. No chest pain but he looks uncomfortable, he is diaphoretic and tachypneic. History of this in the past but he has never needed to come to the hospital for it.
IV, O2, monitor, ABC’s, 12 lead…
You decide to treat him with a short acting medication. He feels odd for a moment, you look at the monitor, you see asystole then this rhythm.
Patient is pale and minimally responsive. You check his blood pressure and it is 70/30 pulse is getting more and more bradycardiac. The ABC’s are helpful in this case but this drug is more important. What is the drug?
Double Derm Bonus Round
April 24th, 2010 by peter_lunny No comments »Case #1
12 yo female presents with this rash on her abdomen, back, and her upper extremity, some scant involvement of the neck with no facial involvement. Mucous membranes not involved.
Temp 100.1 otherwise no complaints. Recent URI did not receive antibiotics. No one in the house sick. Patient c/o mild puritis.
What is the diagnosis? What is the causative pathogen? Is it contagious?
Case #2
16 yo male presents with this puritic rash. The lesions first started on the chest and back without extremity or mucous membrane involvement Patient has been scratching all day. Patient recently had a URI that did not require treatment. Patient denies having this rash prior, but does have a history of eczema/ectopy. No new meds. Patient did not take anything for the itching.
Upon exam patient’s rash on the chest is gone and now it is predominately on the back. Mother and patient are adamant that the rash was on the chest.
What is the diagnosis? What is the treatment?
Case #3
Happy looking 20 month female presents with this rash. No other complaints or lesions on the rest of her body. No recent illness or medications. No one else has the rash at home. No significant medical problems. Patient is afebrile.
Patient eating a popiscle happy, playful and not fussy. Upon exam of the oropharynx the tongue is blue as the popicle she was eating was also blue. No obvious oral lesions, however the inside of the buccal mucosa on the other side of the cheek lesions are hard to palpation.
What is the diagnosis? What is the treatment?
Case #2
April 16th, 2010 by peter_lunny No comments »38 year-old male presents to the ED after a syncopal episode. He was out shoveling snow, felt like his heart began to race and became lightheaded. He awoke lying in his driveway minutes later. He is currently without any complaints. States that he occasional feels like his heart is racing but it never lasts long enough for him to seek medical treatment. His wife saw him pass out in the driveway and insisted that he be seen in the ED.
PMx: none
PSHx: T&A at 8 years of age
Meds: NSAIDs prn
All: PCN
FamHx: adopted
BP 122/78 HR 81 RR 18 T 98.4 PO 99% on RA Blood sugar 112
General appearance: well-appearing, no distress
HEENT: abrasion to right cheek, no boney tenderness, PERRLA, oral mucosa moist
Neck: no c-spine point tenderness, no STS, trachea midline
Heart: RRR, no murmur
Lungs: CTA, no RRW
Abdomen: soft, NT/ND, +BS
Skin: no jaundice, no pallor
Ext: no signs trauma, no point tenderness
Neuro: no focal deficits
I know that you have limited information but what is your diagnosis?
































