If You Haven't Had a Complication, You're Not Doing Enough
Throughout my two short years working in the ICU, I have been able to do many things that caused my heart to race. I’m often the lead during cardiac arrests; I’ve felt the rush of adrenaline from the surrounding cloud of chaos in a decompensating patient’s room; I’ve felt the warmth of blood all over my shoes during a massive GI bleed. I think many of my colleagues would agree these things keep us all on edge - especially at first. But one thing that has always uniquely affected me since the beginning was the stress surrounding performing procedures.
I still remember in training doing my first central line. It was on an intubated patient with an internal jugular the size of China. Despite the hours of research I had done on placing CVLs – learning about the Seldinger technique, mentally rehearsing it from start to finish - I was still incredibly terrified. Trying to appear more experienced than I was, I attempted to gown up by myself; when I failed, the nurse had to take five minutes inching towards the small space behind me to attach the two Velcro pieces in the back. I slowly and meticulously opened my kit and tested every single piece of that kit multiple times, as if releasing and retracting the blade 30 times would somehow improve my luck.
Que 45 minutes later – my first central line sat in all its glory neatly tucked underneath my tegaderm. Despite having reassuring signs that it was correctly placed – my ultrasound image, the lack of high pressure when placing the catheter, the dark oozing blood from each port – I remained in what felt like SVT until the x-ray came. It was confirmed - my first central line was good to go.
Since that time, I have done hundreds more central lines in all sorts of ways. I have done emergent central lines during a code, risky central lines in a coagulopathic patient, and painful central lines in a screaming/delirious patient. However, for the longest time one thing I never experienced was a serious complication. A voice always echoed in my head – “If you haven’t had a complication, you aren’t doing enough”. I had done so many. Why hadn’t I had my complication yet?
One week I was working night shift with one of the PA students on their rotations. I headed to do a central line on a patient for IV access. I quizzed her on the information that I had now become so accustomed to - the equipment needed, the Seldinger technique and the exact steps of placing it that I had memorized through my many times doing it. The actual line went without a hitch. I was able establish solid access to the vessel, threaded the wire without an ounce of resistance, and my ultrasound image with the hyperechoic dot in the vein was textbook quality. “But we always check a chest x-ray for placement,” I had explained to her. We both awaited the chest x-ray while talking about other patients that we had seen that evening.
Then the x-ray came. I pointed out the tip of the central line on the imaging, which directed towards the SVC. For the most part it looked normal but in my head something looked off; I was not sure exactly what but knew this would be a great teaching point. “How do we confirm this is in the vein, not the artery, other than via chest x-ray?” We dove into the differences between the two types of vasculature and eventually got a blood gas of the central line sample. I held the iStat in my hands as the clock on it ticked down to 10, 9, 8. “What would you expect in a venous sample?” I asked; a low PaO2 since its de-oxygenated blood, the student confirmed. I heard the machine begin to rumble, and a result appeared.
PaO2 = 108.
108?! The student looked confused and immediately asked me if that was considered low. No, I answered, it was not. I felt sweat form on my brow. 108?! How can it be 108?! It was very dark blood. The patient’s MAP was 90, and nothing shot out of the needle prior to me inserting the wire. Was he hyperoxic? He was on low vent settings. His ABG drawn before from his radial artery had a PO2 of 110. Was this sample drawn wrong, was it an ABG and not a VBG? Did they mishear?
I instructed the nurse to continue to hold off on using the line and called my attending to notify him. I already knew what he was going to say; hook it up to CVP. Clearly, the CVP will be fine. The pressure was not high when I was inserting it, so it HAD to be a venous tracing. Around this time, the official read came back on the chest x-ray – “Right central venous catheter now in place without pneumothorax”. That was reassuring. It was venous, right?
As we hooked it up to CVP, the waveform appeared.. and it was arterial.
A venous tracing on CVP
An arterial tracing
The student asked if the waveform was normal for a vein. Now with my sympathetic nervous system in overdrive, and more sweat visible around my face, I told her – no, actually, it’s not. I was in near panic. Was my first central line complication actually happening?! I called my colleague working at another hospital who confirmed – “Yup.. That sucks. Definitely arterial, you better call vascular”.
Dejectedly at 3:00 AM that morning I left a message to the vascular surgeon on call. He called me back and I explained my predicament; that the line itself was inserted without complication but it had an arterial tracing on CVP and a PaO2 of 108 on the blood gas. He requested we attach it to an arterial line set-up and call him back. He explained that if it was truly arterial we would be able to get an arterial blood pressure reading. After about fifteen minutes of setting up for an a-line, and attaching it to my central line, the blood pressure finally came back - -2/-1. Venous.
We later found out the patient had a newly found PFO on echo which likely was contributing to this. A patent forman ovale is a small hole between the left and right atria that can result in shunting of deoxygenated/oxygenated blood. The vascular surgeon explained that we had done everything and demonstrated that was indeed venous by evidence of the low pressure. Later that day a CT C/A/P was done (for other reasons) that confirmed it was indeed terminating in the SVC.
Some thoughts -
Evidence suggestive of accessing a vein:
Dark, de-oxygenated blood
Use of IV tube extension sets to measure a manual CVP; feed angiocath over wire and hook up, low pressure —> likely vein
Use of ultrasound guidance when inserting; seeing wire (hyperechoic dot) in the vein
Low pressure on a normotensive patient - e.g. not pulsing out at you
Ways to confirm a central line:
Chest x-ray immediately following the line
Blood gas of a sample from the line; will usually have a low PaO2
Hook it up to CVP and ensure it has a venous waveform
And what I have learned now, if still torn: hook it up to an arterial line set up
Some things that will change my future approach;
Should we should have gone straight to attaching it to an arterial line set-up once the ABG was abnormal? Maybe. But is it realistic to do every time? Probably not given the time and equipment needed – but I would argue it is a way to be more definitive in the setting of contradictory information
Now when checking a blood gas I will likely check a recent echo and checking for a PFO
So it turns out my first major central line complication was not really my first major central line complication. What ended up winning that title? That’s a story for another day.