By Betty Tran, MD, MSc
Assistant Professor of Medicine, Pulmonary and Critical Care Medicine, Rush University Medical Center, Chicago
Dr. Tran reports no financial relationships relevant to this field of study.
SYNOPSIS: In this single-center, prospective, observational study, intraosseous access outperformed central venous catheter placement in terms of first-pass success rates, mean placement times, and complication rates.
SOURCE: Lee PMJ, et al. Intraosseous versus central venous catheter utilization and performance during inpatient medical emergencies. Crit Care Med 2015;43:1233-1238.
During inpatient medical emergencies, response teams are charged with obtaining quick vascular access for the delivery of life-saving medications and fluid therapy. Traditionally, the easiest vascular access has been placement of a triple lumen catheter in the femoral vein, as anatomic landmarks here are often easier to identify than other areas, minimizing the need for ultrasound assistance. Choice of this site over others also allows for easier compression of blood vessels in the event bleeding occurs, avoids unwanted central line complications such as pneumothorax, and avoids multiple personnel working in the same area (e.g., provider at head of bed performing intubation, provider doing chest compressions, etc). In pre-hospital and emergency department settings, however, intraosseous (IO) catheter placement has provided a fast and safe alternative for vascular access, although data on their use in the inpatient setting are limited.
In a single urban teaching hospital over a period of 17 months, Lee et al collected data on emergent central access placement in 79 adult patients, 31 of whom received IO catheters and 48 received central venous catheters (CVC) during medical emergency team (MET) calls. The primary CVC site was the femoral vein (access was obtained without the use of ultrasound guidance), and the primary IO site was the medial proximal tibia, with the proximal humeral head being the secondary target if the first site attempt failed or if there was a contraindication. In their protocol, IO catheters were the first-line access for patients in cardiac arrest and were to be used if a CVC could not be placed after two attempts or within 5 minutes. Rotating house staff on METs were provided monthly simulation instruction in CVC and IO insertion. Most of the CVCs and IOs were placed by postgraduate year 2 and 3 residents, and a more senior resident, critical care fellow, or attending took over the procedure after failed attempts at the discretion of the MET leader. The primary outcome was first-pass success rates for CVC and IO placement. Secondary outcomes included time to successful placement, number of attempts, BMI, anatomical location, number of kits used, and complications of both catheters.
First-pass success rates were significantly higher during IO attempts compared to CVC passes (90.3% [95% CI, 80-100%] vs 37.5% [95% CI, 24-51%]; P < 0.001). Overall success rates were also significantly higher for IO vs CVC placement (96.8% vs 81.3%; P = 0.04). Procedure times were longer for CVC vs IO placement (10.7 vs 1.2 minutes; P < 0.001). Compared to IO placement, mean attempts per patient were higher for CVC (2.8 vs 1.1; P < 0.001), with more CVC kits used per patient (1.3 vs 1.1; P = 0.03). Complication rates were higher in the CVC group compared to the IO group (45.8% vs 9.1%) and were mostly due to arterial puncture or bleeding from the site; the three complications seen in patients receiving IOs were misplacement of the catheter, resulting in extravasation of vasopressors, resultant tissue necrosis, significant pain with infusion, and dislodgement.
COMMENTARY
Although this study was limited by a single center experience, smaller sample size, protocol design limiting IO attempts, and missing data due to lack of collection at night and on weekends, it highlights an intervention that could potentially alter clinical practice for many institutions. IO catheters allow for quick vascular access for fluids, vasopressors, and blood draws. Placement time is consistently faster compared to CVCs. Similar to other procedures, such as CVC placement, which could be considered high acuity/low opportunity situations, simulation training in IO will be helpful to gain practice and avoid complications, although there are no data to suggest learning this skill is more time-intensive or difficult than any other procedure. Although they are not meant to (and should not) replace the use of CVCs in the ICU, they provide an attractive option for vascular access in patients during emergent situations, such as in-hospital cardiac arrests, especially those with compromised vascular access (e.g., end-stage renal disease) without increased complication rates. Further prospective, randomized trials comparing IO to CVC placement in cardiac arrest and other emergent situations would help solidify the role of IO vascular access in these settings.
