POTD: ETT Cuff Leak

>> Why do we care?

• Results in inability to ventilate (massive loss of TV necessitating ETT replacement)

• Results in aspiration of gastric contents or pharyngeal secretions (no proper isolation to protect the lungs)

• Can result in complete loss of airway

>> How does it present?

• Respiratory instability (decreased oxygenation and/or ventilation)

• Gurgling noise

• Decreased tidal volumes

>> Two Major Categories:

• Leaks Around an Intact Cuff/Inflation System:

  • Cuff Underinflation

  • Cephalad Migration of ETT

  • Inadvertent Intratracheal Placement of Gastric Tube

  • Discrepancy Between ETT and Tracheal Diameter

  • High Mean Airway Pressure

• Leaks Due to a Defective Cuff and/or Inflation System:

• Inflation Valve: Can be incompetent as a result of poor manufacturing, mechanical trauma, or even routine connection of syringe

• Pilot Tubing: May be damaged by tube securing devices, accidentally cut, or manufactured poorly

• Pilot Balloon: Can be torn, punctured, or otherwise damaged on teeth or sharp equipment; this can cause leakage of air or failure to inflate altogether

• ETT Cuff: If this occurs, the tube must be changed!

Situation 1: The one-way valve malfunctions, but the pilot balloon and line are intact.

Attach a T-piece connector or a clave to the pilot balloon, and then inflate with a syringe. Clamp the T piece with a hemostat or IV tubing clamp, and disconnect the syringe

Situation 2: The pilot balloon or pilot line is ruptured.

Cut the line below the break. Insert either a blunt needle or a 22G catheter into the lumen of the line. Connect it to a syringe and inflate the cuff. Clamp the line, and cover needle or catheter with a transparent film dressing or clave.

POTD: Hydrofluoric Acid Burn

>> Overview:

• Used in a variety of industries, including plastic, dye, semiconductor, and fertilizer manufacturing, beer fermentation, and in petroleum production

• Also found in rust remover, various pesticides, refrigerants, car wash cleaning products, and detergents

• Cutaneous exposures are most common

• Dilute aqueous HF is a weak acid, but at concentrations > 20%, severe and potentially lethal burns can occur

• HF is lipophilic and highly penetrative; causes deep tissue destruction via liquefactive necrosis

  • Once within the tissues, the fluoride ion complexes with calcium and magnesium, causing their depletion

  • Hyperkalemia results from increased cellular permeability

>> Clinical Presentation:

• Pain out of proportion to the exam; discomfort often described as severe throbbing

• Exposures to concentrations > 50% cause immediate pain and tissue damage

  • This may include erythema, blistering, ulceration, underlying bone damage, and tenosynovitis

• Systemic toxicity develops more slowly

  • Can manifest as nausea, vomiting, abdominal pain, renal failure, hepatic failure, seizure, hypotension, dysrhythmia, or heart failure

• Electrolyte abnormalities (hypocalcemia, hypomagnesemia, and hyperkalemia) are common

• Coagulopathy may develop secondary to hypocalcemia

>> Work Up:

• 12-lead EKG to evaluate for dysrhythmia and interval abnormalities

  • Prolongation of the QTc interval is one of the best indicators of systemic HF toxicity

• Pts with significant exposures require continuous cardiac monitoring

>> Management:

• Irrigation:

  • Immediately irrigate with water for 15-30 minutes to remove and dilute the acid

  • Irrigation will not effectively remove HF that has already penetrated into deeper tissue

• Calcium gluconate gel (topical):

  • Turns the fluoride into an insoluble salt, preventing further absorption

    • This reduces the amount of tissue destruction and systemic toxicity

  • Apply gel to affected areas every 30 minutes

    • Once pain is controlled, reduce frequency to every 4 hours

  • Gel can be prepared by combining 100 mL of water-based lubricant with 2.5 g of calcium gluconate

• Calcium gluconate infiltration:

  • Allows for much greater skin penetration than topical application; its use should be considered for significant burns

  • Infiltration is performed with a small gauge needle (25- or 27-gauge)

    • Inject approximately 0.5 mL/cm2 of 5% calcium gluconate into the affected skin and subcutaneous tissue

    • For finger injuries, do not exceed 0.5 mL per phalanx to prevent an excessive rise in compartment pressure

• Calcium gluconate, intravenous:

  • Should be administered intravenously following significant exposures and in cases of hypocalcemia

  • Intravenous calcium gluconate decreases pain and prevents extension of the burn to deeper tissues

  • For extremity burns, regional intravenous calcium gluconate may be administered via Bier block

    • Tourniquet is placed proximal to burn; calcium gluconate is administered intravenously distal to tourniquet

    • Can inject 10 mL of 10% calcium gluconate diluted in 30 - 40 mL of normal saline and maintain for 20 - 25 min

• Calcium gluconate, arterial:

  • High incidence of complications (arterial spasm, necrosis, dysrhythmia, and vasculitis)

  • No demonstrable benefit when compared to intravenous calcium gluconate for most HF exposures

  • Intra-arterial calcium is theoretically advantageous in severe burns affecting tissues with clear arterial distribution and in small spaces that cannot accommodate large volumes of locally-infiltrated calcium

• **Resolution of pain is a good indicator of treatment efficacy**

>> Non-Dermal Exposures:

• Inhalation:

  • Consider the possibility of inhalational exposure in any patient with HF burns to the face, head, or neck, as well as in burns sustained in confined spaces

  • May cause fever, chills, pulmonary edema, hemorrhage, chest discomfort, cyanosis, and wheezing

  • Obtain chest radiography and provide supplemental oxygen

  • Consider nebulized calcium gluconate (2-3%), PPV, and intubation in severe cases

• Ocular:

  • An ophthalmologic emergency; irrigation is the immediate priority

  • Consider administration of calcium gluconate (1-10%) eye drops

  • Instill 1-2 drops every 2-3 hours into the affected eye(s)

• Fingernail:

  • HF easily penetrates the nail

  • Removal is generally required to apply calcium gluconate gel to affected nailbed