•  In pediatric patients a 20–24 gauge needle may be used for the first cannulation and then exchanged with a larger gauge over a guidewire

•  Proceed as described in the standard landmark technique above, but confirmation of the intravenous location of the guidewire with longitudinal view before vessel dilation

Real-time Visualization of SC

•  Transducer is placed in the infraclavicular groove at the level of the middle or lateral third of the clavicle

•  Axillary vein and artery are imaged as they exit the bony canal formed by the clavicle and the first rib

•  Artery is most commonly cephalad to the vein and noncompressible, and does not vary in diameter with respiration

•  Either transverse or longitudinal view for guide needle insertion as described above

•  Proceed as described with landmark technique followed by confirmation of guidewire location in vein

INSERTION OF A PULMONARY ARTERY CATHETER (PAC) (ALSO SEE CHAPTER 7, ON PERIOPERATIVE MONITORING)

Indications

•  Management of complicated myocardial infarction (ventricular failure, cardiogenic shock)

•  Assessment of resp. distress (cardiogenic vs. noncardiogenic pulm edema, 1° vs. 2° pulm HTN)

•  Assessment of shock

•  Assessment of fluid requirements in critically ill (hemorrhage, sepsis, acute renal failure, burns)

•  Postop management of cardiac pts

•  Need for heart rate pacing

Contraindications

•  Tricuspid or pulmonary valve mechanical prosthesis

•  Right heart mass (thrombus and/or tumor)

•  Tricuspid or pulmonary valve endocarditis

Technique

•  Central venous access as described above

•  Positioning: Floating PA catheter easier in flat or slightly reverse Trendelenburg in contrast to central line placement (Trendelenburg)

•  Aseptic technique: Sterile gown, face mask, gloves, skin disinfection, & whole-body drape

•  PAC setup

•  Calibrate (“zero”) PAC, check PAC for damage, test balloon inflation/deflation

• Connect all lumens to stopcocks, flush to eliminate air bubbles

• Check PAC tip frequency response by touching tip

• PAC threaded through sterile sleeve prior to insertion into cannula

•  PAC inserted percutaneously into major vein (IJ, SC, femoral) via an introducer sheath

• RIJ: Shortest & straightest path

• LSC: Acute angle to enter SVC (compared to RSC or LIJ)

• Fem: Distant sites, difficult if R-sided cardiac chambers enlarged (often fluoroscopic guidance necessary)

•  Insert into introducer maintaining preformed curve (RIJ approach: Concave-cephalad)

•  Once PAC enters RV, a clockwise quarter turn moves tip anteriorly (allows easier passage into PA)

•  After inserting PAC to 20 cm mark (30 cm mark if femoral route used), inflate balloon with air (1–1.5 mL)

•  Always inflate balloon before advancing & always deflate balloon before withdrawal

•  While advancing, waveforms will be observed (distal lumen pressure monitoring):

• RA ≈ 25 cm (RIJ)

• RV ≈ 30 cm (↑ systolic pressure than RA, absence of dicrotic notch)

• PA ≈ 40 cm (↑ diastolic pressure, ↓ systolic pressure)

• PCWP ≈ 45 cm (some damping & ↓ pressure with occlusion of PA)

•  Obtaining pulmonary capillary wedge pressure

• Disconnect breathing circuit

• Determine volume of air in balloon required to obtain a PCWP waveform (volume < half balloon max. may indicate tip too far distal)

• Read PCWP (correlates with LVEDP ≈ 4–15 mm Hg is normal)

• Reconnect breathing circuit, deflate balloon, observe PA waveform return

• PA diastolic pressure usually correlates well with PCWP pressure (should be used as parameter to assess left ventricular filling)

• Withdraw PAC slightly (1–2 cm) to prevent PA rupture from distal tip migration

• Secure catheter sleeve once PCWP is obtained (assure that PCWP pattern is reproducible before removing sterile field)

•  Troubleshooting a coiled/knotted catheter:

• Prevention: Withdraw PAC slowly to ↓ risk of knotting catheter upon itself

• Use fluoroscopy if necessary to remove a knot

• Remove PAC & introducer as one unit if unable to release a knot

• Obtain a CXR to check PAC position

Complication: PA Perforation

•  Predisposed when no wedge pattern evident after deep insertion

•  Circumstances that predispose to PA perforation: Papillary muscle ischemia, mitral stenosis or regurgitation, pulm. HTN, intrapulmonary shunting, LV failure

•  Caution if no definitive wedge pattern is observed (repeated attempts to advance PAC may lead to PA perforation)

•  Coiling or actual false-negative wedging may occur & predispose to PA rupture

DECOMPRESSION OF A PNEUMOTHORAX (NEEDLE THORACOSTOMY)

Indication

•  Tension pneumothorax (symptoms: Hypotension, ↓ SpO₂, ↓ breath sounds & tympanic to percussion on affected site; deviated trachea & mediastinum on CXR)

Technique

•  Insert large bore cannula or needle into 2nd intercostal space on midclavicular line

•  Release pressure in pleural cavity (converts tension pneumothorax → simple pneumothorax)

•  Subsequent chest tube insertion usually required to treat pneumothorax

Complications

•  Lung laceration (esp if no tension pneumothorax present)

•  Reaccumulation of air in pleural space (may be undetected if needle thoracostomy becomes dislodged)

INSERTION OF A NASOGASTRIC TUBE (NGT)

Indication

•  Decompression & emptying of stomach (after RSI, prior to laparoscopy, GI surgery)

•  Aspiration of gastric fluid (lavage to detect intragastric blood in the setting of GI bleed)

•  Tube feeding

•  Drug administration

Contraindications

•  Base of skull fractures, severe facial fractures (esp to nasal bones)

•  Obstructed esophagus or airway

Technique

•  Measure tube length (tip of pt’s nose to ear & down to xiphoid process)

•  Lubricate end of plastic tube being inserted into anterior nares

•  Advance tube through nasal cavity & into throat

•  Pass pharynx rapidly with gentle continuous pressure to go into stomach
(if pt awake, encourage patient swallowing)
(if pt asleep, consider use of laryngoscope to visualize entry into esophagus)

•  Confirm placement by CXR (safest), aspiration or injecting air (stomach auscultation)

Complications

•  Malplacement (endotracheal, intracranial)

•  Esophageal perforation

•  Pulmonary aspiration, pneumothorax

•  Nose erosion/bleeding, sinusitis, sore throat