Thoracentesis


  INDICATIONS
Evacuation of air: Anterior approach
      ■ Temporary treatment of tension pneumothorax
      ■ Treatment of stable pneumothorax
Evacuation of fluid: Posterior approach
      ■ Analysis of pleural effusion
      ■ Treatment of symptomatic pleural effusion or tension hydrothorax

CONTRAINDICATIONS
Absolute: Needle insertion through an infected area
Relative: Readily available tube thoracostomy if needed
■ Bleeding diatheses or on anticoagulants when treating stable pts

 TECHNIQUE
Evacuation of air: Anterior approach
        ■ Patient supine, head elevated 30 degrees
        ■ 14- to 18-Ga needle with or without catheter
  ■ Needle is inserted in second intercostal space, midclavicular line over third rib to avoid nerve/vessel damage.
  ■ Rush of air will confirm placement, catheter, if used, can be advanced over needle.
  ■ Attach to one-way drainage system to prevent pneumothorax reaccumulation.
        ■ Sterile glove finger can be used as a one-way valve tied to needle at one end with small hole on other end.
 

Evacuation of fluid: Posterior approach
        ■ Patient sitting upright:
                ■ 18- to 22-Ga needle is inserted at midscapular line or posterior axillary line below the top of the fluid determined by percussion, but not below weight intercostal space. Catheter (if used) is then advanced.
        ■ Patient supine with head elevated:
                ■ 18- to 22-Ga needle is inserted at midaxillary or posterior axillary line in the fourth or fifth intercostal space.


 COMPLICATIONS
■ Pneumothorax
■ Diaphragmatic, liver, intercostal nerve/vessel, or spleen injury

 INTERPRETATION OF RESULTS
■ For diagnostic thoracentesis, send for LDH, glucose, protein, cell count, and differential.
■ If needed, send for amylase, triglyceride level, cholesterol, complement, RF, CEA, G-stain, cultures, AFB, fungal cultures, cytology, pH.
■ Exudate: Inflammation causing increased capillary permeability (pneumonia, TB, CA, other)
        ■ Fluid/plasma protein >0.5
        ■ Fluid/plasma LDH >0.6
        ■ Fluid LDH >200 IU/mL
        ■ Fluid protein >3 g/dL
        ■ Specific gravity >1.016
■ Transudate: Ultrafiltrates of plasma through intact capillaries (CHF, cirrhosis, hypoproteinemia, other)
        ■ Fluid/plasma protein <0.5
        ■ Fluid/plasma LDH <0.6
        ■ Fluid LDH <200 IU/mL
        ■ Fluid protein <3 g/dL
        ■ Specific gravity <1.016

 
Table 71-2 Definitions of Terms and Devices
Single aspiration Insertion of a needle or catheter, aspiration of air using an attached syringe, and immediate removal of the device.
Heimlich valve A plastic chamber with a one-way flutter valve, with one end inserted into the chest tube or catheter and the other end to the drainage bag. Fluid and air will not reflux back into the pleural cavity (Figures 71-5 and 71-6).
Needle aspiration 18-Gauge needle (provided in kits as an 8F catheter over an 18-gauge needle).
Small-size catheter < 14F.
Small-size chest tube 10F-14F.
Moderate-size chest tube 16F-22F.
Large-size chest tube 24F-36F.