What about a longer needle ? Many catheters used for needle decompression are 5 cm in length; however, some have access to 8 cm angiocatheters. A analysis by Clemency and colleagues found that in order to achieve a success rate of 95%, we would need a catheter at lease 6.4 cm in length [8]. Similarly, Laan and colleagues conducted a pre-post retrospective study in an EMS system that switched from using 5 cm catheters to 8 cm catheters with an increase in success rate (48% vs 83%) [6]. For a life saving, last ditch effort, I'm not sure that 95% success rate is adequate when alternatives exist.





We don’t identify this site well [10,11]. A 2005 paper by Ferrie and colleagues had 25 emergency physicians name the correct side for needle thoracentesis and label this site with a pen on a male volunteer (erased between providers). Nearly all participants were ATLS certified within the past 10 years.

88% (n=22) named the correct site (one additional person did name the 5ICS AAL).

Only 15 of the 25 participants (60%) could correctly identify the 2ICS MCL [10].

In another study, Inaba and colleagues trained 25 US Navy corpsmen on needle decompression, using both the 2ICS MCL and the 5ICS AAL. The corpsmen then performed needle decompression at both sites on randomly selected cadavers, bilaterally.

Mean distance from the correct location: 3.1 cm 2ICS MCL vs 1.2 cm 5ICS AAL

Correct placement (ICS +/- 5 cm): 15/50 (30%) 2ICS MCL vs 41/50 (82%) 5ICS AAL

Limitations: This study had multiple outcomes and no power analysis was performed [11]

I think much of this is because we underestimate the length of the clavicle. It's easier when you can see the chest wall bones but we don't have this advantage in the clinical setting. On a person, the midclavicular line often seems fairly lateral.





Important structures surround the 2ICS MCL. As mentioned above, we seem to have a tough time finding the 2ICS MCL [8,9]. There are important structures in this vicinity, particularly if the tendency is to go more medial than the actual midclavicular line, including the internal mammary artery and contents of the superior mediastinum. Naturally, should an individual placing a needle in the 4/5ICS AAL go too caudal the possibility exists for the needle to enter the liver or spleen but the study by Inaba and colleagues suggest we may be better able to identify this space [9].





Given the literature, it seems that at this time should a needle be placed aiming for the 2ICS MCL for needle decompression and fail, this is a failure of education and changing our knowledge base rather than a patient-based failure. We should know better.





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