Hello, I'm Dr. Heather Lee Bailey, an emergency medicine intensivist and a past president of the society. This presentation will focus on emergencies that patients may experience when the environment causes trouble. While you may not commonly care for these type of patients in your ICU, these are the types of emergencies that you may experience in your daily life, such as at a sporting event, any other outdoor venue, or even while on vacation. We will cover the topics of extremes of temperature, initial burn care, including inhalation injury and those experiencing electric injury, discuss the transfer criteria for burn center for patients, and we'll review environmental challenges that occur in the water, such as drowning and diving injuries. I'm going to start with heat stroke. Heat stroke is the number one cause of environmental death in the United States and probably worldwide. There are two types of heat stroke. There is the exertional heat stroke that occurs typically in healthy individuals, such as athletes running marathons or in military recruits. You get a rapid rise in core temperature, the body produces excess heat, and the body is unable to cool itself. Contrary to classic heat stroke, there is frequently sweating, so that hot, dry skin does not apply typically to the patients experiencing exertional heat stroke. Versus classic or non-exertional heat stroke, this is when there's heat waves with sustained environmental heat. More common in the elderly, they have decreased thirst, so they get dehydrated easily, they have multiple core morbidities, there are multiple medications that put patients at risk, and this is the classic hot, dry skin. Mortality even when identified and treated can be as high as 60%, and it's important to know that even with appropriate treatment, there is significant morbidity, including about a third of patients are going to have some element of cognitive and motor dysfunction where they may not be able to return to their daily life, especially work. Three main causes. First is heat, increased heat production, a variety of different types of metabolic and other processes such as status epilepticus, agitation or substance use, there is the inability to lose heat, you have decreased heat loss, can be environmental, can be medication related, there are multiple medications that can put patients at risk for not being able to appropriately dispense heat, and then impaired mobility. Extremes of age, they are unable to get themselves out of the hot environment because of physical or mental issues, or again, substance abuse puts individuals at risk for this. There are several prognostic indicators, the older one is, the less likely that they will do well, the higher their temperature, or if shock is present, especially if organ dysfunction persists for more than several days, these individuals are not going to have a good outcome. If the patient has neurologic recovery, it starts to occur during cooling, their mental status improves, they get more back to their baseline, this is a good prognostic indicator. The things that we can control as clinicians are how long the patient stays hot, so the sooner they are identified, the sooner that they are cooled, and how fast you cool them, these will affect their patient's long-term outcome. So identify them quickly, cool them rapidly. As you can see, all organ systems may be affected, and I have a star at the brain because this is part of the criteria for heat stroke, where you have central nervous system dysfunction and a temperature of greater than 40, but all systems can be affected, GI, gastrointestinal, you can have ischemia and translocation of bacteria that can lead to other problems, and the renal system is also significantly affected, both from direct heat-related injury and from the development of rhabdomyolysis, a combination of heat breakdown of the muscle, or if the individual is spending a significant amount of time down in the hot environment. This flowchart is from the CDR that was recently released in Critical Care Medicine in Congress in 2024, and is in the, I believe, March issue of CCM for 2024, and as is the prior diagram. So this flow diagram starts with, you identify the individual, they have that temperature greater than 40 and the altered mental status, and just like every other patient, you start with the ABCs, oxygen if needed, evaluate them for airway protection, but begin immediate cooling, that is imperative, and you start with whatever you have available, be it ice packs, be it cool water, be it fans, start with what is readily available while you're looking for more definitive methods such as tubs or bags that you can put, submerge the individual with cold water or ice water immersion. Start IV fluid. Now not all patients are going to require a large volume of IV fluid, it depends on why they developed heat stroke in the first place. Obviously if they have rhabdomyolysis, you want to evaluate and give them appropriate fluid administration for appropriate urine output to clear the muscle breakdown. If there is no rhabdo or no AKI, evaluate them potentially with ultrasound or other ways that you use to guide your fluid administration, and look and see if shock is present. And as you're treating these individuals, you are constantly reassessing with the goal of getting their temperature to 39 degrees or less. Once you've reached that goal of 39 degrees sonograde, you need to stop cooling and assess them at that point. Is their mental status still altered? If it is, then they may need further imaging such as CT scan, EEG, looking for signs of intracranial hypertension, or other causes. If their mental status is improved, then you're going to continue with good supportive care and monitor for complications. An ICU management is how we would care for any other individual with good supportive care, monitoring each system appropriately, looking for coagulation disorders, renal dysfunction with acute kidney injury. But I want to caution you that one of the things that is a little atypical about this is you have to monitor these patients for frostbite and for skin breakdown, especially if you have them in cold water immersion or in ice water immersion. These patients may develop a cold injury. The other thing is if you're using cold water immersion and ice water immersion is you need to be in good communication with your environmental staff because wet floors are very frequent and common in caring for these individuals, and it is not uncommon for staff to have a slip and fall and injury because there tends to be, unfortunately, water everywhere as the ice starts to melt. Key points for heat stroke is rapidly cool them to less than 40 degrees or 102 Fahrenheit. It may require multiple different methods, especially if you're unable to immerse the individual in ice water or cold water immersion. You want to prevent shivering because shivering is going to increase and maintain the hyperthermia of the patient, so benzodiazepines are the appropriate or the most commonly used drug for this, medication for this, and avoid antipyretics and norepinephrine because that can decrease cutaneous heat exchange. Going to the other extreme of cold-related injury, typically radiation is responsible for normal heat loss of the body. However, in cold injury, it is usually by conduction and convection, and wet clothes and wind dramatically increase heat loss anywhere from 5 to 25 times more likely, especially if they've been immersed in cold water or in snow. There are risk factors, anything that will cause peripheral vascular disease, and with frostbite, even though frostbite is not going to be the main reason that these individuals get admitted to the ICU, you must be mindful of it. The superficial frostbite don't really have any evidence of tissue loss, and underneath its tissues are soft, versus in deep frostbite, the tissues are going to feel rock hard. We talk about this because in the patients that are hypothermic, you should evaluate them for frostbite on all areas and appendages. The goal is to prevent further tissue loss. If you're able to splint and elevate the extremity, that may be helpful. If the patient does not have acute kidney injury or no other contraindication, nonsteroidals may be given to inhibit the arachidonic acid cascade that can promote frostbite injury. Topical aloe vera can also be used. If the blisters are intact, they recommend do not debride them, but you can aspirate the clear blisters. It's important to allow these wounds to demarcate, and that can be anywhere from two to three months duration, unless there's evidence of infection. There are categories of accidental hypothermia, and that is considered any core temperature under 35 degrees Fahrenheit or 95 degrees Fahrenheit, which is mild to most severe. There are two categories of severe. Severe level three is individuals are unconscious, are, as you can see, extremely cold, however, they still have vital signs present, versus the most severe, stage four, is there are no vital signs present, and the patient has apparent death. This flow diagram is from the European Resuscitation Council on management of hypothermia, and it's a little bit difficult to look at, but you can review it yourself separately, but the key question is, if they're cold and cold to the touch, are vital signs present, yes or no? If yes, you follow with, are they impaired, are they altered, and follow those pathway. If there's no vital signs present, first you want to evaluate them, should you continue? Is there evidence of, such as decapitation, or transection of the trunk, or whole body decomposition? Obviously, you would not continue forward in these individuals. Now, in patients who've had buried in snow, or prolonged time in cold water, there are also criteria for stopping as well. If there is a snow impaction in the airway, and they've been buried in an avalanche for more than an hour, the recommendation is not to continue. But you can follow through these flow diagrams to the point of the patient is either rewarmed and doing well, or if not, you start CPR. If they have no vital signs present, and there is no indication to not continue, I know there's a lot of double negatives in that, but if there's a reason that you should continue, you start CPR, keeping in mind that this can be for hours. So if you have a compression device, this is the time to utilize it, because this may be hours resuscitation. There are some scoring tools that may be helpful. There's the 5A score that can be used in all patients with hypothermia, and that looks at age. There are ADLs prior to becoming hypothermic. Are they in cardiac arrest? Are they acidemic? And what is their underlying albumin? What is their nutritional status? And based on that score, you can get a percentage of what the likelihood of these patients' ability to recover, and I like the fact that they at least start at 60 versus a lot of the trauma data that starts at age 50, but still at age 60, you're at increased risk for having a poor outcome. Then there's the HOPE score, which is a hypothermic outcome prediction for using extracorporeal life support. It looks at age, it looks at gender, how long have they been hypothermic, is there evidence of asphyxia, just ask that question of were they a victim of submersion in liquid that was cold, or in an avalanche, how long is the CPR, what's their serum potassium, and then looking at the temperature, and this will give you a percentage as well of what the likelihood of survival and potential outcome would be. First question, all of the following are correct about hypothermia except, one, central venous pacing should be avoided because of heart irritability, two, hematocrit increases as core temperature decreases, three, a rectal probe is indicated for temperature monitoring in moderate to severe hypothermia, or four, the presence of an Osborne wave is indicative of hypothermia. And the answer is three, the rectal probe is not appropriate. So the heart is very irregular when it's cold, and just the act of moving a patient from the MS stretcher into the hospital bed, or emergency department stretcher, or from the ED to the ICU can trigger the patient to go into ventricular fibrillation. It's important to monitor the core temperature and using esophageal temperature probe, and the lower third is the most accurate, and that is where you want your probe to be. In patients who are severely hypothermic, the probe may very well be in frozen stool, so you won't have an accurate temperature. The Osborne wave, as you can see depicted here. Its height is actually proportional to the degree of hypothermia. So while you're trying to get an actual core temperature, you can't register, your thermometer won't register, you're looking for your rectal probe or you're trying to get an esophageal probe in, you can look at the height of the Osborne wave. That will tell you how severe the hypothermia is. Oxygen dissociation curve is shifted to the left. And for every drop in one degree sonic rate of temperature, the hematic rate is going to increase by 2%. Just like in hyperthermia, there are several rewarming, there are several options, passive and active. And start again with whatever is readily available, get them out of the wet clothes, get the warm blankets on, warm the room up. And you may need extracorporeal life support. You can see here the difference when you have support versus without support, significant change in temperature of the ability to rewarm. This is why it takes hours. Even with extracorporeal life support, not gonna raise more than 8 to 10 degrees per hour. So if your patient's temperature is in the low 80s, it's going to take quite some time to get them to a reasonable temperature. If the patient is in cardiac arrest, initiate CPR. As I mentioned, it can take hours. Get your compression device. If you have the ability to use some type of extracorporeal support, you want to initiate that as soon as possible. Typically, medications and defibrillations do not work until the patient's core temperature is about 30 degrees sonograde. It is recommended that you can try one round of defibrillation and one round of medications prior to getting to that temperature, but do not continue that unless there is response because otherwise you can have buildup of that medication. So only one round prior to getting the temperature up to somewhere between 86 and 90 degrees. There are several complications that you need to monitor for. You can have core after drop, and that's when the periphery is warm first. So if you start warming with just warm blankets, heating pads, bear huggers while you're trying to get internal rewarming or extracorporeal life support started, they can get core after drop. As the cold blood returns to the core, the temperature can drop further. Patients are very coagulopathic. Remember that our enzymes typically are temperature related and they affect the coagulation cascade. Rhabdomyolysis is very common in these individuals because of prolonged downtime, and hypotension is common. Patients develop severe dehydration from cold diuresis as the hematocrit becomes concentrated. Next we're going to focus on burns. Burns are the fourth most common trauma worldwide. They injure about 11 million people annually. Every year in the U.S. about half a million people seek care for burns, and about 40,000 patients end up being hospitalized. There is increased risk of death. The larger the burn, the deeper the burn. Older age and smoke inhalation all contribute to risk of death. There are newer terms that have been used for quite some time now. The degrees terminology should not be used. So it's superficial, partial thickness, full thickness, or subdermal. To evaluate the burn size, there are several different scoring systems, including just using the patient's palm and hand is about 1% of their total body surface area. There are a scoring system that uses age plus your total body surface area that can give you prognostic for poor outcome with minimal to no survival, and that may be helpful for family decision making. Just like any other wound, you need to clean and debride the wounds. Keep them moist, but you don't want to use any topical moisture ointments for about any longer than a week. Sulfosulfadiazine can be used on the body, but should not be used on the face, and it does impede reepithelialization, so you want to avoid using that in superficial wounds. You can use bacitracin on the face, and don't forget about medical-grade honey that can be used in addition or instead of these other agents. If there is circumferential burns, you need early escharotomy, and wounds that have been open for at least two weeks, most likely, if you're not already at a burn center, are going to need to be transferred to a burn center. There are several different formulas that you can use to estimate volume loss and replacement. Parkland versus the modified Brook. Parkland tends to overestimate volume required, but it's important that whichever formula that you are using, the first half is given in the first eight hours, and then the second half of the calculated loss is given in the second, in the next 16 hours. Burn patients are very hypermetabolic. It could be helpful to cool the room. It's important to have good analgesia, because this will drive the hypermetabolic state if the patient is in severe pain. You may consider giving oxandrolone, which is a testosterone analog. It's been shown to promote anabolism in older patients. It takes effect in about two weeks, but it has been shown to decrease the length of stay in older patients suffering burn. Enteral nutrition is very important, especially in the burn patients, and you want to use a lower respiratory quotient formula. Insulin resistance is common. In the pediatric literature, there is some suggestion that propranolol may be helpful. There is no studies that are, at this time, helpful in the adult care patients. So there's a hypermetabolic response. It would be more common when they have more than 20% of total body surface area, get muscle wasting, multiple organ failure, and death. There's some recent evidence that suggests that early nutrition is important for less complications, and they're talking early nutrition within four to six hours of injury, not four to six hours in the ICU, but four to six hours from time of injury. The energy requirement is based on the total body surface area burned, and you can see the protein requirement that is recommended, but it has been shown that patients will have less overall complications, including less development of sepsis and less pneumonia. Now, the majority of us don't work in a burn center, so who should be transferred to the burn center or at least be considered for transfer? Those that have partial thickness burns, burns to pertinent areas such as hands, feet, genitalia, perineum, those that have electric burns, including those that have been hit by lightning, chemical and inhalation burns, those who are going to need long-term burn rehab, and individuals who the trauma from the burn is greater risk for morbidity and mortality than any other injury that they have been affected with. If your patient has suffered a burn injury from fire, they all should be given 100% humidified oxygen. There's multiple studies where we've tried to limit the amount of oxygen. Looking at, does hyperoxia cause significant harm? Well, at least for the moment, in burn patients, they should all start with 100% humidified oxygen. Should be intubated early, especially if there's evidence of any type of burn or concern for airway compromise if there's circumferential neck burns. You should also evaluate and treat, potentially for carbon monoxide and cyanide exposure. Very high lactates can be suggestive of cyanide exposure. Typically, cyanide levels are not going to come back in an expedient manner. Most centers, this would be a send-out test, so you should have high suspicion if the patient was especially in a closed space where the burn occurred, and they have a very high lactate level. It can give thiocyanate, hydroxycobalamin, and for carbon monoxide, the treatment is hyperbaric therapy and 100% oxygen. Next question. 44-year-old male was found unconscious in a house fire. He was placed on 100% oxygen with a non-rebreather mask. He is currently sleepy but answering questions. He has no obvious airway compromise and has minor burns on his extremities. He reports headache and vomiting. Which of the following indicates the need for hyperbaric oxygen therapy for carbon monoxide poisoning? Carboxyhemoglobin level of 20, headache, loss of consciousness, or vomiting? And the answer is loss of consciousness. So any history of loss of consciousness is an indication for hyperbaric. Carbon monoxide level is greater than 25%. If the patient is pregnant, if they're in coma, if they're having seizures, or if they've had a prolonged carbon monoxide exposure, found down in a house where they had a heater burning or brought their grill inside when they have not had no heat, these are the individuals who you should definitely consider transferring for hyperbaric oxygen. Inhalation injury. If the burn patient has an inhalation injury, it's an independent predictor of mortality. In fact, it's one of the more common causes of mortality with burns is the inhalation injury. There's direct toxic effect. The smoke has a lower molecular weight so it allows the particles to get deep into the alveoli. You can have direct burn damage as well from the heat. It can cause inflammation and disruption of the ciliary function. Leads to thick secretions, atelectasis, and impaired gas exchange. It's very common to get bronchoconstriction and bronchospasm. You get increased vascular permeability and vasodilation, which leads to exudates and cast formation. You get atelectasis and alveolar collapse and vasoconstriction leading to impaired oxygenation. There are some that recommend obtaining a CT to evaluate for injury prediction. If you're bronching these patients, there is a scoring system that gives you the level of injury and that should be documented. Typical early management should include bronchodilators, including potentially nebulized epinephrine, mucolytic agents to help break down the mucus, and there is suggestion that nebulized N-acetylcysteine with heparin improves mortality by improving lung compliance and improving the edema and decreasing the length of time on ventilator. There are two types of current, AC and DC. AC, alternating current, is household current. It is typically more dangerous than direct current. At just such a low milliamprage, at just 6 to 9 milliamps, you get that let-go threshold where your muscles contract and the individual cannot let go of whatever live wire that they have touched. They get cardiac depolarization and V-fib at higher milliamps. Direct current is sort of like blast effect. These individuals can be thrown and get associated blunt trauma. High-voltage batteries, electronics, lightning, these things can cause your victim to be thrown as well. The challenge is that a lot of times there is minimal external damage, and so you may come across a victim who is on their own by themselves and you don't really know what happens and you don't really have evidence of trauma. So it does make it challenging. In patients that are in cardiac arrest, they can be in cardiac arrest, they can have LOC, they can have seizures. Muscle pain and rheumatoid myelitis is very common. Burns in these individuals typically are not going to correlate with the level of injury, so just having a minor burn does not mean that they haven't had a severe electric shock. It's important to evaluate both the eyes and the ears. Ears, just like you would in a blast injury, they may have ruptured tympanic membranes. This may be the only external sign of trauma, so it's very important that you evaluate the tympanic membranes. Eye findings, you're going to have burns and detachment and late development of cataracts, so this is important if your patient has a prolonged time in the ICU, is evaluating that, but also when they are discharged from your ICU to make sure that you're in handoff that is known to evaluate for delayed cataract development. Another clue can be if your patient presents and has a posterior shoulder dislocation. This is classic from a blast or being thrown injury, so if they present with minimal trauma and they have a posterior shoulder dislocation, you should be aware that they've had some type of potential electric injury and have been thrown. Obviously, you want to monitor their cardiac status, looking for any type of dysrhythmia or block, manage their rhabdo, treat them for burn. Don't forget about tetanus in these individuals. Electric injury puts patients at risk for both arterial and venous thromboembolic disease. The last couple of topics we're gonna talk about individuals who have problems in the water. First is drowning. The definition that has been for the last 20 plus years is the process of experiencing respiratory impairment from submersion or immersion in a liquid. And it is drowning, fatal drowning or non-fatal drowning. The near drowning terminology is been removed and it should not be utilized at this time. It's either a fatal or a non-fatal drowning. There's about half a million deaths worldwide per year and this is probably an underestimate because not all countries are able to keep excellent records and many of these individuals don't enter into the healthcare system because they are pronounced on site so they may not be counted. Also, drowning deaths do not include natural disasters such as floods or hurricanes. Those individuals are not counted in drowning deaths. There's about 4,000 deaths per year in the United States and these have increased since pandemic. It's the number one cause of death in boys between five and 14 worldwide and it's top five causes of death in children under the age of 14 in about half of all countries that keep records. And for everyone that is dead, everyone who dies, there's about four more evaluated in the emergency department. Risk-taking behaviors are as you would expect. Teenagers, if there's substances involved, can be from adequate supervision and just like some of these other entities, medications can put you at risk. Now, provided there's not a medical cause for drowning such as you've had a myocardial infarction and drowned from that or a seizure, for whatever reason, you panic, you're caught in a riptide, you go underwater, you're not able to get yourself out of your situation, you have panic, you lose your breathing pattern, you start holding your breath and you're struggling to stay above water. Unfortunately, your drive to breathe is so strong that you get aspiration and sometimes reflex laryngospasm, you lose consciousness, you become apneic and the individual drowns. In cold water, you get early vasoconstriction, shifts the blood to the central core and the receptor sends a volume overload, leads to decreased antidiuretic hormone, leads to hypovolemia and hypotension and this is important in these individuals who spend any significant time in water, especially cold water is that when they are removed from the lake or ocean or whatever they're in is they need to be brought out in a horizontal position because if they are brought out vertical, the central blood just then will pull and drop away from the cardiopulmonary function and these individuals can have cardiovascular collapse. So it's important to remember that anybody who's been in water for a significant period of time is going to be hypovolemic. Fresh versus salt water, typically it was thought to be very important but honestly, it's not really that relevant. In general, in non-fatal drownings, it's low amount of liquid that is aspirate, only a few cc's per kilo but they have decreased lung compliance, you get VQ mismatch, you get shunting, you get lung injury and so fresh versus salt water is not really that important but what is in the water is more important if there's any contaminants. You know, was this individual in some type of tank that had chemicals in it? Was this a drowning event after an accident and they fell into a ditch and they aspirated contents that have some type of fungus or other organism that can lead to a significant illness? So the contaminants are a bigger concern than whether it was fresh or salt water typically. Management, another exception to the rule, this is traditional ABCs if you're involved in the initial care of these individuals because the majority of these individuals have respiratory arrest and pulmonary dysfunction. So ABCs, breathing instead of the, how we're focusing more on compression. Most of these individuals do not have cervical spine injury. The studies have shown unless they were at risk and they were diving into a pool or into a lake and C-spine precautions are not recommended because they typically get in the way unless you have high suspicion for a drowning injury. Just like with the hypothermic patients, get them out of their wet clothing, provide them with supplemental oxygen. You want to maintain their sat better than 94%. They may be bronchospastic. You can give them beta-2 agonists and any individual who is symptomatic after six hours should be admitted. And if you have diffuse pulmonary findings, should be at least in a step down if not in the ICU. There are some classifications of lung findings and I think the important thing is that if you have any kind of findings, you should be admitted to the hospital. Any organ system can be infected in the drowning event. And it's important to learn the context of what happened. Is this an individual who was swimming in an area where it was only a few feet of water and had they just stood up, they would have been fine. You need to look for another event. They could have some type of dysrhythmia or prolonged QT. Most of the rest of this is fairly straightforward and the one individual you should worry about in multi-system trauma is in individuals who have either fallen or intentionally jumped from a height into water. Some recent evidence shows that in patients who need to be intubated and you've had to increase positive PEEP to improve oxygenation, should leave them for 48 hours before trying to wean them because you want to allow the surfactant to regenerate. So we don't want to start weaning right away. You want to leave them for a good solid 48 hours to allow for improvement in lung functions. So in summary for drowning, because I know there's a lot of information, is if you have an individual in your ICU and they don't have a good reason to have a drowning event, you must look for a medical cause. Prolonged QT can be very common, especially in cold water and then autonomic conflict. Cold water can cause complete autonomic dysfunction. There's no role for steroids or antibiotics on presentation. There's no proven early predictors of neurologic outcome. It unfortunately really still is just time and good supportive care. And one of the key things is that the majority of drownings are felt to be preventable. So you really should push for universal CPR training in the communities where you live. There is some recent evidence that if you have a drowning event and you were in fresh water, that you should cover for resistant gram-negative erymonas. I don't think that's gonna be on the boards, but in your clinical practice, there is the difference here with this fresh water drowning about making sure you have a broad spectrum coverage for gram-negatives. Last question, which of the following is correct about diving-related injury? One, decompression sickness from nitrogen bubbles is typically present within the first few minutes after a dive. Two, stroke-like symptoms from cerebral embolization are the most common presentation of an arterial gas embolism. Three, it is safe to fly the same day following a shallow dive of less than 30 feet to depth. And four, pneumothorax is a common result of barotrauma. And the answer is two, stroke-like symptoms from cerebral embolization are the most common presentation of an arterial gas embolism. Diving is very common, certainly in the United States. The good news is that there's not a lot of at least reported dive injuries, but unfortunately, the dive injuries that occur, a significant percentage of them are fatal. Barotrauma is the most common, and it's when you get an air-filled body space fails to equalize to the pressure with the environment. You can have problems on descent from under-pressurization or on ascent from over-pressurization, which typically are more severe and typically more life-threatening. Risk factors, key things to ask is if you're caring for these individuals, did they have a post, did they fly post-diving? What's the depth that they went to? How long did it take for their ascent? How long were they at depth? And how long was the overall dive time? Not typical questions that you think about unless you are a scuba enthusiast yourself. So at depth, there are two main problems. You can get nitrogen narcosis, and those are the very deep dives, and that has to do with the gas ratio in the air tank. Get altered, hallucinate, decrease coordination. They can also get oxygen toxic, where they get nausea, vomiting, dizziness, confusion, and seizure, neither of which would be a good thing when you're 50 to 100 feet down under the water. So treatment for that is if your buddy becomes altered or you start to become altered, a slow ascent, and making sure that you've had the appropriate gas mix for the depth of the dive, and it's important of never diving alone, always having a buddy that can recognize when you are in distress. So on ascent, you get the expansion of gas. The most common is vortigo. If a blocked eustachian tube, you get tympanic membrane rupture, vomiting, loss of hearing, you get altered. Some individuals may panic. They can get breath holding. Leads to hemoptysis and chest pain. You can get subcutaneous air. You can also develop a large pneumothorax, which would require a chest tube. But barotrauma is the most common. The most severe on ascent is a gas embolism. Typically, it's gonna occur during or within the first few minutes of being out of the water on ascent. You get gas ruptures of the alveoli. You get air that enters the pulmonary venous circulation, travels to your heart and your systemic circulation. Cerebral embolization is the most common, so you're gonna get sudden stroke-like symptoms, seizure, confusion. 100% oxygen, give them IV fluid, place them in a supine position, and hyperbaric oxygen is the treatment. So if you don't have a dive chamber, you wanna get them to a dive chamber as soon as possible. Now, decompression sickness is fairly common, and that has to do with the nitrogen bubbles in the tissue. Typically, that is going to occur more than 10 minutes after they've been out of the water. There's two types. There's the bends, which can be pain. Shoulder pain is typically the most common. In the skin, the joints, the extremities. Type two is central nervous system, ear, and lungs. That is obviously the more concerning and the more life-threatening treatment, though. 100% oxygen, get them to hyperbarics, keep them supine, give them IV fluid. Just a few reminders. Extremes of temperature in the heat. For a heat stroke, you wanna rapidly identify them, rapidly cool them to less than 40 degrees sonograde, but remember to stop cooling once they get to about 39 to 40 degrees. In individuals who are hypothermic, you want to warm them until they're at least 32 degrees. No one is dead until they're warm and dead. In burn patients, if you're not a burn center, you should consider transfer for the reasons we talked about. Inhalation injury. If you're concerned for inhalation injury, not only does that increase their risk of death, but you should also consider carbon monoxide and cyanide poisoning. Electric injury, especially if those are hit by lightning, can be very misleading. Do not rely on external findings. And then for issues in the water. For drowning, remember it is traditional ABCs, as the problem is typically respiratory component. And then timing of weaning. If you've needed to increase PEEP for oxygenation, leave them for at least 48 hours to allow for surfactant replenishment. And if you have an individual with diving injury, the good news is it's 100% oxygen and a hyperbaric therapy, regardless of whether this is an oxygen problem or a nitrogen problem. Thank you for your attention.

environmental emergencies

heat stroke

frostbite

burn injuries

electric injuries

drowning

decompression sickness

hyperbaric therapy