Drowning: Pediatric Clinical Scenario (Nursing)

00:00 Hi, I'm Doctor Rhonda Lawes and I'd like to welcome you to this clinical scenario.

00:05 In this scenario we're going to look at a pediatric cold water drowning victim. Now, there are some special considerations for pediatric drowning victims and we're going to walk through those, together.

00:16 Cold water drowning in children presents a really unique physiological response and clinical considerations that are different from drowning in warmer water or in adults. So, this case study you and I are going to do, highlights the unique physiological advantages that children have in cold water drowning and emphasizes the importance of you having very specialized knowledge and protocols when we treat these patients.

00:40 Now, you're going to understand why standard resuscitation timeframes should be extended in pediatric cold water submersion cases, and why seemingly futile cases can sometimes have remarkably positive outcomes.

00:53 The mammalian diving reflex is one of the major reasons that children have an advantage over adults, because this is a protective physiological response that is particularly pronounced in children.

01:07 So let's take a look at the trigger and the mechanism.

01:09 If a child's face is suddenly immersed in cold water, so that means typically below 70°F or 21°C, the body initiates several reflexive responses.

01:20 They go into immediate bradycardia.

01:23 That means that it will slow their heart rate down about 50 to 30%. They're going to have peripheral vasoconstriction.

01:32 That means the blood vessels are going to constrict in their limbs and in their skin, shunting all that blood toward their core organs, their brain, their heart, and their lungs.

01:41 This is also going to reduce their metabolic rate and therefore their oxygen consumption. This reflex is so remarkable.

01:49 I want to go over that again.

01:51 So you really understand how amazing this is.

01:54 So when you have the mammalian reflex kicked in.

01:58 The patient can conserve oxygen for just their vital organs.

02:01 Remember, vasoconstriction shunts blood toward the body right to the core of the body. This is particularly going to help the brain, which is our biggest concern in cases of drowning.

02:13 Now this effect also reduces the metabolic demands of the tissues which mean the tissues need less oxygen.

02:21 It's going to slow the development.

02:22 It's going to buy us time to avoid an extended hypoxic injury. So that means the brain tissue can be viable for a longer period of time, even if they've been submerged for a prolonged period of time.

02:37 So the most important takeaway for you is hypothermia protects a child's brain. Now, this cold water rapidly cools a child's body and it induces this hypothermia.

02:49 Now I want to break it down a little bit about what is so significant about this neuroprotection. Why is it that a child cools faster? Well, they have rapid cooling.

03:00 They cool 2 to 5 times faster than adults in cold water.

03:03 Now, why is that? Well, just look at the body of a child.

03:07 They have a higher surface area to mass ratio.

03:10 They have less subcutaneous fat for insulation, and their thermal regulatory mechanisms are less developed.

03:17 So those are three reasons that children cool 2 to 5 times faster than adults in cold water.

03:24 So why is this good? Because it protects their brain.

03:28 There are some neuroprotective mechanisms.

03:30 Now. There are some pretty detailed reasons, but I'm just going to go over the ones that are most important. When the brain in the body is cooled rapidly, it'll decrease the cerebral metabolic rate.

03:42 That means that what the brain needs for oxygen is going to be decreased.

03:47 It's estimated that this metabolic rate in their brain decreases 6 to 7% for each one degree Celsius drop in temperature, so that is why it is neuroprotective.

03:59 Now when you've got this decreased metabolic rate, the brain needs less oxygen and less glucose to still survive. Now there are several other reasons, but those are the most important ones I want you to remember.

04:13 Now there are some known temperature threshold effects.

04:16 The degree of protection correlates with the water temperature.

04:20 So if it's water temperature that can cause mild hypothermia, that's going to offer some protection.

04:25 If the water temperature provides moderate hypothermia, that's going to be significant protection.

04:30 And if the water temperature causes severe hypothermia, this is actually the best case scenario, because this can allow for remarkable recoveries even if the patient has been with prolonged submersion.

04:43 So that's good news for your patient.

04:45 The combination of the mammalian diving reflex and hypothermia creates a situation where extended resuscitation efforts are warranted.

04:54 It's what we should do and it's what we will do.

04:57 So, mammalian diving reflex and hypothermia, is what causes us to extend the resuscitation longer than we normally would.

05:05 Now there's a medical axiom.

05:08 And sometimes you hear people say they're not dead until they're warm and dead.

05:13 Now, this is particularly applicable to pediatric cold water drownings.

05:17 See, children are amazing.

05:19 They've been successfully resuscitated with good neurological outcomes after being submerged for times exceeding 30 to 60 minutes in very cold water. They had an absence of vital signs for extended periods, and their core temperature was as low as 13 to 19°C, which is 55 to 66°F.

05:42 So we already talked about that.

05:44 In the case of a hypothermic pediatric patient that the one of the differences extended resuscitation efforts.

05:51 We will go longer with a pediatric patient who's hypothermic.

05:55 This could be potentially up to hours rather than the usual timeframes.

06:00 We're going to watch them closely for arrhythmias.

06:03 We're going to keep a close eye on their body core temperature.

06:06 We may even consider slowing down the rate of CPR now as we're warming them up. It has to be gradual and it has to be slow.

06:15 Typically one half to one degree Celsius per hour.

06:19 Remember we've got that core temperature monitoring going on throughout the resuscitation. If necessary, the team will consider ECMO if it's available for rewarming and support of this client.

06:31 Now, this is where it becomes difficult when we start talking about assessment, because determining true cardiac arrest versus severe bradycardia might be difficult to do because their pulse may be really hard to find.

06:44 We have to try to distinguish between hypothermic rigidity and rigor mortis.

06:49 When you look at their pupillary responses, they may be altered by the hypothermia.

06:53 And looking at and interpreting ECG changes may also be difficult because of the hyperthermia.

06:59 You see J, or Osborn waves.

07:01 As a nurse, I want to talk about the clinical implications and the nursing considerations for caring for a pediatric client experiencing drowning in cold water. You already know that the resuscitation duration is going to go longer than we normally would, and you want to make sure the client has been rewarmed to at least 32 to 34°C before considering terminating the resuscitation.

07:27 The Rewarming Techniques are going to be an important part of that.

07:30 There's passive external warming.

07:32 If it's just mild hypothermia, there's going to be active external warming, warm blankets or forced air warming, or there might even be active core rewarming for moderate to severe hypothermia.

07:44 That could be warm IV fluids, warm humidifier oxygen body cavity lavage, or even ECMO. Now let's imagine that you are through the code.

07:53 The patient has been resuscitated.

07:55 Now it's your job to take care of them post-resuscitation.

07:59 What are the things you're going to be thinking about? What are your priorities? Well, you're going to have a targeted temperature management plan.

08:08 The physician is going to let you know which temperature range the client needs to be in.

08:12 And that may be a mild therapeutic hypothermia.

08:15 You're going to watch carefully for reperfusion injury and cerebral edema.

08:20 This patient may have delayed neurological problems and it may take several days to accurately assess these.

08:27 You're going to keep doing serial neurological assessments so you're aware of any changes. And our goal is to prevent secondary brain injury. It means you want optimal oxygenation making sure they're perfused, keeping adequate glucose levels and again doing those neuro checks.

08:45 Now, keep in mind this is the best part of this whole series.

08:49 Children have survived with intact neurological functions after being submerged for incredibly long periods of time and were even clinically dead. So keep in mind a pediatric drowning victim isn't dead until they have been warmed, so this will help you know that you're going to have extended resuscitation efforts and may even have a fantastic outcome. Now, some cases we talked about even shown recovery after 30 to 60 minutes being submerged in very cold water.

09:21 So you as the nurse, are going to facilitate the family understanding the reasons for the extended resuscitation.

09:27 You want to give them realistic, but not prematurely pessimistic, or overly optimistic ideas about their prognosis.

09:36 Just do what you can to support that family through an uncertain outcome.