Updated: Oct 24, 2021 Published Oct 20, 2021
MunoRN, RN
8,058 Posts
Either this nurse has bad luck or there's something fishy going on and he really did kill a bunch of people, but the argument made in court makes no sense. Despite that, it worked, he was found guilty.
The nurse was found guilty of Capital murder resulting from supposedly killing 4 patients by injecting air into their arterial lines after open heart surgery resulting in strokes.
I'm really not sure how that's possible, these were presumably radial arterial lines, I'm not clear how air injected into a radial artery "travels straight to the patient's brain", which was the prosecutor's claim. I can't find that any medical professionals supported this theory, but there were doctors who testified that this isn't really possible based on how blood flow in the body works.
Jury finds former Tyler nurse guilty of capital murder (MSN.com)
Defense presents other possible cause for patients deaths in fourth week of nurse trial (ketk.com)
BeatsPerMinute, BSN, RN
396 Posts
https://www.ahajournals.org/doi/10.1161/STROKEAHA.119.025340
2 hours ago, BeatsPerMinute said: https://www.ahajournals.org/doi/10.1161/STROKEAHA.119.025340
The mechanism there is more likely; venous air embolism with a right-to-left intracardiac shunt.
The proposed way this nurse did this was to inject air into the radial artery with a syringe, which would cause impressive SQ emphysema in the hand but not much else.
As I've been thinking about it more though, there would be ways to basically hookup an air compressor to the patient's arterial line, using hospital air and the pressure bag fill tube that has a luer-lock port on it. This would be fairly obvious in other ways but potentially could cause air to move against the arterial flow to the brain.
offlabel
1,645 Posts
No way to get a real answer from secular news. Cerebral air embolisms don't cause people to 'crash'. A bolus of air into a PA (hence the 'arterial line') catheter would if it were big enough. But that something like that to be missed on post would be unusual, I'd think, and not 4 times.
Seen an air bolus into a radial artery and it results in a completely blanched hand for a few minutes.
the article I posted earlier from AHA about strokes makes some sense to me on how this could be possible.... if the person successfully only killed 4 people, I wonder if he had tried this method on more esp considering the number of patients that come out with an Aline after these kinds of procedures...
im curious about pathophysiology - my ICU preceptor DRILLED into me that you get rid of all bubbles when setting up an arterial line. When prepping the bag (before attaching to patient) she would have me hold the bag upside down to eliminate ALL air from the bag, fill the chamber FULL of fluid, and turn the bag back right side up, flush the lines fully and clear the line of even the tiniest microbubbles, before it was all good to hook up to the patient. she was a very OCD (and awesome) preceptor.
I did forget all of the rationales she shared with me as this was years ago... in summary, usually was "and this is why by NOT doing XYZ , or by DOING XYZ, is how you could end up killing your patient" (poor little new ICU nurse me back then was terrified XD ... preceptor was awesome and taught me critical thinking, patho, and primed me to be a very vigilant, safe, and detail oriented nurse)
Say a person changed out the A-line saline bag and did not eliminate the air. or someone else had prepped it and had not eliminated air from the bag or the chamber. my preceptor would kill me if she knew I was saying this but its not a huge, immediate safety issue as long as you watch your line....however, with that, you wouldnt even need a syringe to bolus this patient with air - its possible I guess to take a fully inflated, pressure-ized saline bag, hold it up side down, and pull on the flush tail, which could give them a sig amt air bolus followed by flush with strong force. and with enough flush and force, force the air to travel far up enough, and maybe if flushed far up enough, maybe the air could travel retrograde through the system? and that leading to a stroke? sometimes it can cause immediate effects, but not always (just depends on the patient).
this is just a guess... its possible that he could have hurt more patients at varying levels... embolism is a possible risk in the procedural world, so it would be possible for any MD to be like "unfortunately, this was one of the risks of the procedure" and then no one thinks twice about it ...
unfortunately the article doesnt go into great detail. if a nurse wants to hurt or kill patients, they'd do it in a sneaky way so they're not caught. if a sick SonOFaB "nurse" wanted to cause potential harm to people, they'd do it in a way that is not obvious... in ways that doesnt cause a patient to immediately code (or there's little risk of them immediately coding), with the knowledge that XYZ complications post procedure happen anyway...
if there was a trend in this nurse's patient outcomes, care, or if another nurse/colleague noticed that his practices were a bit odd... im sure someone started digging and eventually put two and two together. its a pretty big allegation
I'd love to hear more from more experienced nurses what their thoughts are
summertx
186 Posts
On 10/19/2021 at 11:46 PM, MunoRN said: Either this nurse has bad luck or there's something fishy going on and he really did kill a bunch of people, but the argument made in court makes no sense. Despite that, it worked, he was found guilty. The nurse was found guilty of Capital murder resulting from supposedly killing 4 patients by injecting air into their arterial lines after open heart surgery resulting in strokes.
This 'hospital' allowed the nurse to work after the first 3 deaths, what the heck made them investigate and fire the nurse after the 4th?
glasgow3
196 Posts
"This 'hospital' allowed the nurse to work after the first 3 deaths, what the heck made them investigate and fire the nurse after the 4th?" A bad Press-Ganey maybe?
Robmoo, ADN, BSN, RN
162 Posts
On 10/20/2021 at 5:51 PM, BeatsPerMinute said: the article I posted earlier from AHA about strokes makes some sense to me on how this could be possible.... if the person successfully only killed 4 people, I wonder if he had tried this method on more esp considering the number of patients that come out with an Aline after these kinds of procedures... im curious about pathophysiology - my ICU preceptor DRILLED into me that you get rid of all bubbles when setting up an arterial line. When prepping the bag (before attaching to patient) she would have me hold the bag upside down to eliminate ALL air from the bag, fill the chamber FULL of fluid, and turn the bag back right side up, flush the lines fully and clear the line of even the tiniest microbubbles, before it was all good to hook up to the patient. she was a very OCD (and awesome) preceptor. I did forget all of the rationales she shared with me as this was years ago... in summary, usually was "and this is why by NOT doing XYZ , or by DOING XYZ, is how you could end up killing your patient" (poor little new ICU nurse me back then was terrified XD ... preceptor was awesome and taught me critical thinking, patho, and primed me to be a very vigilant, safe, and detail oriented nurse) Say a person changed out the A-line saline bag and did not eliminate the air. or someone else had prepped it and had not eliminated air from the bag or the chamber. my preceptor would kill me if she knew I was saying this but its not a huge, immediate safety issue as long as you watch your line....however, with that, you wouldnt even need a syringe to bolus this patient with air - its possible I guess to take a fully inflated, pressure-ized saline bag, hold it up side down, and pull on the flush tail, which could give them a sig amt air bolus followed by flush with strong force. and with enough flush and force, force the air to travel far up enough, and maybe if flushed far up enough, maybe the air could travel retrograde through the system? and that leading to a stroke? sometimes it can cause immediate effects, but not always (just depends on the patient). this is just a guess... its possible that he could have hurt more patients at varying levels... embolism is a possible risk in the procedural world, so it would be possible for any MD to be like "unfortunately, this was one of the risks of the procedure" and then no one thinks twice about it ... unfortunately the article doesnt go into great detail. if a nurse wants to hurt or kill patients, they'd do it in a sneaky way so they're not caught. if a sick SonOFaB "nurse" wanted to cause potential harm to people, they'd do it in a way that is not obvious... in ways that doesnt cause a patient to immediately code (or there's little risk of them immediately coding), with the knowledge that XYZ complications post procedure happen anyway... if there was a trend in this nurse's patient outcomes, care, or if another nurse/colleague noticed that his practices were a bit odd... im sure someone started digging and eventually put two and two together. its a pretty big allegation I'd love to hear more from more experienced nurses what their thoughts are
The main reasons for purging all air from and art line is that number one air is compressible. Since it is compressible it will mute your wave form and destroy the accuracy of your pressures readings. Number two any air traveling into the blood stream from and art line is going to travel down that artery to the hand and potentially obstruct smaller vessels and cause ischemia in the hand. Since air injected into an art line has to travel through the capillaries long before returning to the heart, I'm at a loss as to how this will cause a cerebral embolism. The newsie must have been confused or mis-spoke.
51 minutes ago, Robmoo said: The main reasons for purging all air from and art line is that number one air is compressible. Since it is compressible it will mute your wave form and destroy the accuracy of your pressures readings. Number two any air traveling into the blood stream from and art line is going to travel down that artery to the hand and potentially obstruct smaller vessels and cause ischemia in the hand. Since air injected into an art line has to travel through the capillaries long before returning to the heart, I'm at a loss as to how this will cause a cerebral embolism. The newsie must have been confused or mis-spoke.
I am sincerely curious. I'd rather be wrong here and now vs in a clinical situation. What are your thoughts about the link I posted earlier in the thread? Its:
(I'm stuck on the info around Figure 3, which is approx halfway through this article)
wernicke, BSN, RN
44 Posts
It’s not clear to me either what the mechanism was but he did confess on the phone with his ex wife. He apparently didn’t realize it was being recorded and was admissible.
https://www.ketk.com/news/crime-public-safety/william-Davis-murder-trial/convicted-christus-nurse-searched-a-list-of-serial-killers-by-number-of-victims-weeks-before-his-arrest/
On 10/20/2021 at 3:51 PM, BeatsPerMinute said: the article I posted earlier from AHA about strokes makes some sense to me on how this could be possible.... if the person successfully only killed 4 people, I wonder if he had tried this method on more esp considering the number of patients that come out with an Aline after these kinds of procedures... im curious about pathophysiology - my ICU preceptor DRILLED into me that you get rid of all bubbles when setting up an arterial line. When prepping the bag (before attaching to patient) she would have me hold the bag upside down to eliminate ALL air from the bag, fill the chamber FULL of fluid, and turn the bag back right side up, flush the lines fully and clear the line of even the tiniest microbubbles, before it was all good to hook up to the patient. she was a very OCD (and awesome) preceptor. I did forget all of the rationales she shared with me as this was years ago... in summary, usually was "and this is why by NOT doing XYZ , or by DOING XYZ, is how you could end up killing your patient" (poor little new ICU nurse me back then was terrified XD ... preceptor was awesome and taught me critical thinking, patho, and primed me to be a very vigilant, safe, and detail oriented nurse) Say a person changed out the A-line saline bag and did not eliminate the air. or someone else had prepped it and had not eliminated air from the bag or the chamber. my preceptor would kill me if she knew I was saying this but its not a huge, immediate safety issue as long as you watch your line....however, with that, you wouldnt even need a syringe to bolus this patient with air - its possible I guess to take a fully inflated, pressure-ized saline bag, hold it up side down, and pull on the flush tail, which could give them a sig amt air bolus followed by flush with strong force. and with enough flush and force, force the air to travel far up enough, and maybe if flushed far up enough, maybe the air could travel retrograde through the system? and that leading to a stroke? sometimes it can cause immediate effects, but not always (just depends on the patient). this is just a guess... its possible that he could have hurt more patients at varying levels... embolism is a possible risk in the procedural world, so it would be possible for any MD to be like "unfortunately, this was one of the risks of the procedure" and then no one thinks twice about it ... unfortunately the article doesnt go into great detail. if a nurse wants to hurt or kill patients, they'd do it in a sneaky way so they're not caught. if a sick SonOFaB "nurse" wanted to cause potential harm to people, they'd do it in a way that is not obvious... in ways that doesnt cause a patient to immediately code (or there's little risk of them immediately coding), with the knowledge that XYZ complications post procedure happen anyway... if there was a trend in this nurse's patient outcomes, care, or if another nurse/colleague noticed that his practices were a bit odd... im sure someone started digging and eventually put two and two together. its a pretty big allegation I'd love to hear more from more experienced nurses what their thoughts are
When I was first trained to critical care, more than a decade ago, it was explained to us that the "double spike" method for removing all the air from the system was out-of-date, but that you would still come across nurses who swore by this method, and we were encouraged to show the 'old-school' nurses why their practices were out-of-date.
The main reason for leaving at least some air in the drip chamber was to be able to assess the amount of flush flowing during a fast-flush. When the drip chamber is full you really don't know if the line is flushing or not, and therefore can't assess whether the lumen is fully patent or not.
The other reason is that there is no real benefit from removing every last bid of air from the drip chamber. Even if the bag goes dry, there isn't enough air in the drip chamber to make it's way to the patient. In order to infuse air to the patient there would need to be a leak in the system, in which case purging all the air is of no benefit whatsoever.
But even if some air were to make into the arterial circulation in the radial artery, it's just going to go into the hand, which certainly isn't ideal but isn't at all life-threatening.
In this case however, if your goal was to introduce enough air to cause a clear medical problem then that's certainly achievable, particularly if you utilize the medical air outlet, which supplys compressed air at 50 mmHg and more.
11 hours ago, MunoRN said: When I was first trained to critical care, more than a decade ago, it was explained to us that the "double spike" method for removing all the air from the system was out-of-date, but that you would still come across nurses who swore by this method, and we were encouraged to show the 'old-school' nurses why their practices were out-of-date. The main reason for leaving at least some air in the drip chamber was to be able to assess the amount of flush flowing during a fast-flush. When the drip chamber is full you really don't know if the line is flushing or not, and therefore can't assess whether the lumen is fully patent or not. The other reason is that there is no real benefit from removing every last bid of air from the drip chamber. Even if the bag goes dry, there isn't enough air in the drip chamber to make it's way to the patient. In order to infuse air to the patient there would need to be a leak in the system, in which case purging all the air is of no benefit whatsoever. But even if some air were to make into the arterial circulation in the radial artery, it's just going to go into the hand, which certainly isn't ideal but isn't at all life-threatening. In this case however, if your goal was to introduce enough air to cause a clear medical problem then that's certainly achievable, particularly if you utilize the medical air outlet, which supplys compressed air at 50 mmHg and more.
.. OK so it is possible?