Nasogastric Tubes and Therapeutic Procedures

Nurses manage various therapeutic devices and procedures that carry significant risks if not properly maintained. This section covers nasogastric tubes, chest tubes, and other common therapeutic procedures essential for NCLEX success.

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Nasogastric (NG) Tubes

Purposes of NG Tubes

Tube Types

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NG Tube Placement Verification

Initial Placement: X-ray is the Gold Standard

X-ray confirmation is required before using a newly placed NG tube for feeding or medication administration.

Ongoing Verification Methods:

pH Interpretation:

• pH < 5 = Gastric placement (stomach acid)
• pH 6-7 = Possible intestinal or respiratory placement
• pH > 7 = May indicate respiratory placement (DANGER)

Important: NEVER use auscultation alone to verify placement. Air can be heard over the stomach even with respiratory placement.

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Feeding Through NG/Enteral Tubes

Preparation:

1. Verify placement (pH or X-ray)
2. Assess gastric residual volume
3. Check tube patency
4. Verify correct formula and rate

Preventing Aspiration:

Gastric Residual Volume (GRV):

• Check before each bolus feeding or every 4-6 hours for continuous feeding
• Return aspirate to stomach (contains electrolytes)
• Hold feeding if GRV exceeds threshold (usually 250-500 mL per facility policy)
• Notify provider for persistently high residuals

Tube Patency:

• Flush with 30 mL water before and after feedings
• Flush before and after medication administration
• For continuous feeding: flush every 4 hours
• Use warm water if clogged (avoid cranberry juice - no evidence it works)

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NG Tube for Decompression

Purpose: Remove gastric contents to relieve distention, prevent aspiration, or rest the bowel

Suction Settings:

• Low intermittent suction for Salem Sump (to protect gastric mucosa)
• Blue pigtail (air vent) should remain OPEN and above stomach level

Nursing Care:

• Assess for placement before suctioning
• Monitor color and amount of drainage
• Document output as gastric drainage
• Assess for electrolyte imbalances (loss of Na, K, Cl, H+)
• Provide mouth care (patient is NPO)

Common Complications:

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Chest Tubes

Indications

Chest Drainage System Components

Assessment

Tidaling:

• Normal fluctuation of water level with respiration
• Rises with inspiration, falls with expiration (spontaneous breathing)
• Opposite pattern if on mechanical ventilation
• Absence of tidaling may indicate lung re-expansion OR tube obstruction

Air Leak:

• Continuous bubbling in water seal chamber indicates air leak
• Can be from patient (expected with pneumothorax initially)
• Can be from system (loose connections - check all sites)
• Intermittent bubbling with coughing is normal

Nursing Care

Emergency Situations:

Documentation

• Color, consistency, and amount of drainage
• Presence of tidaling
• Presence of air leak
• Patient's respiratory status
• Dressing condition
• Patient position and comfort

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Other Therapeutic Procedures

Paracentesis

Purpose: Remove fluid from peritoneal cavity (ascites)

Nursing Care:

• Have patient void before procedure (prevents bladder perforation)
• Position patient upright or on side
• Monitor vital signs (hypotension from fluid shift)
• Measure abdominal girth before and after
• Monitor for hypovolemia post-procedure

Thoracentesis

Purpose: Remove fluid or air from pleural space

Nursing Care:

• Position patient sitting up, leaning forward over bedside table
• Monitor for pneumothorax after procedure
• Assess breath sounds before and after
• Monitor for respiratory distress

Lumbar Puncture

Purpose: Obtain CSF sample, measure pressure, administer medication

Nursing Care:

• Position in fetal position (knees to chest) or sitting leaning forward
• Post-procedure: Keep patient flat for 1-4 hours (prevents headache)
• Encourage fluids post-procedure
• Monitor for headache, assess neurological status

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On the Exam

The NCLEX frequently tests:

• NG tube placement verification (pH < 5, X-ray gold standard)
• Aspiration prevention (HOB elevation, residual checks)
• Chest tube management (keep below chest, never clamp without order)
• Emergency situations (tube displacement, system problems)
• Patient positioning for procedures

Priority Tip: For NG tubes, always verify placement before administering anything. For chest tubes, if you see continuous bubbling in the water seal chamber, check all connections for air leaks. If the tube comes out, cover with petroleum gauze taped on three sides.