Décompression à l'aiguille: Pas fiable

Does needle thoracostomy provide adequate and effective decompression of tension pneumothorax?

Martin M et Al. J Trauma Acute Care Surg. 2012;73: 1412-1417

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La décompression thoracique est une des mesures qui vise à réduire le nombre de morts évitables. Il s'agit d'une procédure mise en oeuvre peu fréquemment. L'exsufflation à l'aiguille est la méthode enseignée. Il existe beaucoup de débats concernant le lieu de ponction (plutôt par voie axillaire et non par voie antérieure), la longueur du cathéter (certains proposent 8 cm au risque de ponction parenchymateuse et des gros vaisseaux), le diamètre. Le travail proposé est très intéressant car il exprime toute les réserves qui doivent encadrer ce geste qui ne semble pas aussi efficace que cela car outre les problèmes mécanique il apparaît bien qu'un cathéter de 14G risque d'être insuffisant. On rappelle quand même que la thoracostomie au doigt est toujours possible et que votre doigt a de fortes chances de mesurer 8 cm donc de pouvoir pénétrer dans un thorax après création d'un stomie intercostale à la pince de monro-kelly.

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BACKGROUND:

Tension pneumothorax (tPTX) is a common and potentially fatal event after thoracic trauma. Needle decompression is the currently accepted first-line intervention but has not been well validated. The purpose of this study was to evaluate the effectiveness of a properly placed and patent needle thoracostomy (NT) compared with standard tube thoracostomy (TT) in a swine model of tPTX.

METHODS:

Six adult swine underwent instrumentation and creation of tPTX using thoracic CO2 insufflation via a balloon trocar. A continued 1 L/min insufflation was maintained to simulate an ongoing air leak. The efficacy and failure rate of NT (14 gauge) compared with TT (34F) was assessed in two separate arms: (1) tPTX with hemodynamic compromise and (2) tPTX until pulseless electrical activity (PEA) obtained. Hemodynamics was assessed at 1 and 5 minutes after each intervention.

RESULTS:

A reliable and highly reproducible tPTX was created in all animals with a mean insufflation volume of 2441 mL. tPTX resulted in the systolic blood pressure declining 54% from baseline (128Y58 mm Hg), cardiac output declining by 77% (7Y1.6 L/min), and equalization of central venous pressure and wedge pressures. In the first arm, there were 19 tPTX events treated with NT placement. All NTs were patent on initial placement, but 5 (26%) demonstrated mechanical failure (due to kinking, obstruction, or dislodgment) within 5 minutes of placement, all associated with hemodynamic decline. Among the 14 NTs that remained patent at 5 minutes, 6 (43%) failed to relieve tension physiology for an overall failure rate of 58%. Decompression with TTwas successful in relieving tPTX in 100%. In the second arm, there were 21 tPTX with PEA events treated initially with either NT (n = 14) or TT (n = 7). The NT failed to restore perfusion in nine events (64%), whereas TT was successful in 100% of events as a primary intervention and restored perfusion as a rescue intervention in eight of the nine NT failures (88%).

CONCLUSION: Thoracic insufflation produced a reliable and easily controlled model of tPTX. NT was associated with high failure rates for relief of tension physiology and for treatment of tPTX-induced PEA and was due to both mechanical failure and inadequate tPTX evacuation. This performance data should be considered in future NT guideline development and equipment design