"My name is Bijan Teja. I'm an assistant professor of critical care medicine and anaesthesia at the University of Toronto and a staff physician at St. Michael's Hospital.

What are the unmet needs of patients with CVC placements?

I think the unmet need really, in my opinion, you know, my PhD, is focused on vascular access for critically ill patients. And, you know, the unmet need is really, how can we deliver the medications we need, such as vasopressors, which, you know, a large proportion of our patients need, while giving them the least number of complications possible. And I don't think we've figured that out yet because, you know, when. When we place central lines routinely, you know, we. What we've found in our study, which we'll talk about, is that we are exposing patients to a 3% risk of major complications. And, you know, I'd like to think that with. With a lot of the new, newer techniques and newer options we have, that we can reduce that percentage.

Could you tell us about the methodology behind your research?

Yeah, so we did, you know, we wanted to give people a concrete percentage of. When I put a central line in, what is my risk of complications? And so we did a systematic review initially, it started as 2015 to 2020 to get, you know, contemporary complication rates, and then we updated to 2023's. So it was a systematic review and then a bayesian network meta analysis to determine the overall rate of complications from central lines.

What are the key findings?

I think there are a few very important findings from the study. First, we were especially interested in major complications. So arterial cannulation, pneumothorax, deep venous thrombosis and central line associated bloodstream infection, those are the things that really require major intervention or can prolong ICU stay or can sometimes even result in death. And so the first finding was that when we pulled the rates of complications from those studies and ran Markov simulations to determine if we placed a central line for somebody for just three days, what would be their rate of major complications? We found that it was 30.2 out of 1000 catheters, or about 3%. The second major finding was that ultrasound guidance for placement reduced the rate of major complications substantially for. Especially for immediate insertion complications like pneumothorax and arterial cannulation.

How should these findings inform and influence practice?

I think when I started practise, I remember, actually, I was a first year resident, the first time I ever had to, you know, place a central line in the community as a, you know, as a bedside clinician. And I, you know, I was very nervous, and appropriately so, because there's so many things that can go wrong with these. With these lines. And, you know, and so I struggled a bit and then, you know, luckily there was an attending physician from another service who was there and he tried to help and, you know, he, you know, fortunately, you know, we got air in the syringe, we knew that there was a high risk of pneumothorax. And, you know, sure enough, the next day that patient developed a giant pneumothorax and the chief resident called me and said, you know, like, I saw your patient had pneumothorax and, you know, but the reality is you put enough of these central lines in and, you know, you're going to get complications. And, you know, that patient just needed it for vasopressors. And at that time, eight years ago, it was sort of the norm that anybody who needed vasopressors just got a central line and, you know, you were just going to accept that many of them ended up having these complications. Whereas now, you know, I think things have shifted in many ways. You know, first, many centres, including ours at St Michael's Hospital, you can now give vasopressors through peripheral IV's for, you know, we say up to 72 hours. Other centres have longer periods and, you know, up to a certain dose, we say 0.3 micrograms per kilo per minute of norepinephrine. And so now, you know about. From the other research we've done, we've shown that about 50% of patients with septic shock and other forms of shock can just avoid a central line altogether and have their vasopressor delivered peripherally.

But also, I'm very encouraged by newer techniques like midlines, which have been increasing in popularity, which some centres in the US, I know, have just switched from central lines to almost exclusively midlines, and even for vasopressin and other drugs. And so I think what the implication for me is that a lot of times we can avoid traditional central lines. We can reduce the complication rates by becoming familiar with ultrasound and using it. And when alternative things like midlines, which we have another study ongoing to determine the complication rates of those. But it looks from other, like research like they're probably lower than for central lines. And so when we can use alternatives to central lines, I think it's very beneficial for our patients. The risk of extravasation is extremely low and almost all of those cases can be managed conservatively with things like phenolamine and without any sort of tissue injury or tissue necrosis. And so I think minimising the use of central lines when we can and when clinically appropriate is going to be very beneficial for patients.

What further study is needed?

I'm really looking forward to a few sort of avenues of research. The first is that the systematic review we did, there's also a component on peripheralized IV's and a component on pics and midlines. And I'm really curious to see what that, you know, three days of sort of line use with those, what the rates of major complications are going to be and how they're going to compare to central venous catheters. And I suspect for medlines, it will probably be substantially lower, and something that may convince hospitals we currently don't use them, but may convince us and others to start using them. And I'd also like to see more clinical studies and where we compare different vascular access strategies. There are some that have been published with large numbers, but they're mostly retrospective, and I think these findings ideally would be validated in prospective studies.”