December 8, 2023

Welcome back to Pharmacy Phriday.  In this installment we focus on Calcium, a medication that is rarely used within the UH EMS system and prehospital setting in general.  Records from our 2022 Health EMS reports indicate its use only 73 times system wide. 

Calcium is listed in the UH protocols in two forms: Calcium Chloride and Calcium Gluconate.  The majority of UH squads are probably supplied with Calcium Chloride.  It is important to be aware of which medication one is supplied and given as the dosing is different.  Calcium chloride (13.6 mEq calcium) provides 3 times more elemental calcium versus calcium gluconate (4.56 mEq).  Be sure to check your supply!

UH protocol indications for the use of Calcium include the commonly labeled uses of hypocalcemia (whether due to calcium channel blocker poisoning or other causes) and hypermagnesemia.  The protocols also include Calcium’s use or consideration in what is considered off-label yet common uses, which include poisoning or over-dose of cardiac drugs such as calcium channel blockers, beta-blockers, hyperkalemia, and the dialysis patient in arrest. 

Calcium plays an extremely important role within the body. The vital functions of calcium are seen in the contractility of myocardial and smooth muscle cells, peripheral vascular resistance, as well as in the coagulopathy of the blood.  In cases of an overdose of a calcium channel blocker, it is critical to flood the body with additional Calcium.  In cases of electrolyte imbalances such as hyperkalemia, whatever the cause, Calcium is administered to stabilize the cardiac membranes and reduce the chance of cardiac arrest.

Treatments for beta blockers and Calcium channel blockers are similar, sometimes requiring the “kitchen sink” in correcting electrolyte imbalances and resulting in myocardial depression, bradycardia, and hypotension.  The order of medications will change somewhat, starting with push dose Epinephrine in the beta blocker protocol and starting with Calcium in the Calcium Channel blocker protocol.  In both cases, Calcium may be beneficial due to the inotropic and systemic vascular resistance properties mentioned above.

Dialysis patients are prone to chemical imbalances, and Calcium can benefit many of them. Patients who missed dialysis may be hypocalcemic and/or hyperkalemic. In these types of scenarios, Calcium should be administered alongside Albuterol to patients with wide QRS complexes or peaked T waves. These EKG changes, along with a flattening P wave and prolongation of the PR interval, are considered classic changes seen in hyperkalemia.

For deteriorating patients exhibiting a super wide ECG or sine waves on their EKG (probably indicating extreme hyperkalemia and a peri-arrest situation), protocols jump to Calcium and Sodium Bicarbonate to prevent cardiac arrest. If your dialysis patient is in full arrest, they should also receive a combination of Calcium and Sodium Bicarbonate. 

CAUTION:  DO NOT MIX THESE DRUGS!  FLUSH THE IV LINE BEFORE GIVING THE OTHER MEDICATION!!

Calcium solutions should only be administered via the IV or IO route.  Never give Calcium IM.  Tissue necrosis and sloughing are a serious complication.  It is also of concern if the IV infiltrates.  It is widely suggested that when administering Calcium, the provider uses large veins.  The use of small hand or foot veins is not recommended. Be sure to monitor the IV site closely during administration. If there are signs the medication has infiltrated, the provider should stop immediately and discontinue the IV line.  Do not flush the line anymore. 

When administering Calcium, the medication should be given slowly. Avoid rapid boluses as this can cause arrythmias. Monitor the patient’s vital signs, with special attention to the ECG and blood pressure.  Signs and symptoms of other adverse reactions to watch for include hot, tingling sensations, nausea, and seizures. 

The usual dosing for Calcium Chloride in the adult patient is 1 Gram given as a slow push over 2 minutes.  The pediatric dosing is 20 mg/kg over 10 minutes, to a max dose of 1 Gram.  Dosing for Calcium Gluconate 1-3 Grams as a slow IV/IO.  The pediatric dose for Calcium Gluconate is 60 mg/kg over 10 minutes to a maximum dose of 3 Grams.  Once again, confirm the Calcium solution provided and remember that Calcium Chloride is three times as potent compared to Calcium Gluconate.

UH protocols list no contraindications to the use of Calcium in the emergency setting. 

In closing, we want to thank you again for all you do! Stay safe!!

Sincerely,



The UH EMS-I Team

University Hospitals

December 23, 2022

Dear Colleagues,

Welcome back. In this Pharmacy Phriday, we will attempt to finish our review of medications used in treating Hydrofluoric Acid (HF) exposures. In previous editions, we studied the use of Zephiran Chloride soaks, Calcium Gluconate 2.5% gels, Calcium Gluconate 2.5% flushes, and Calcium Gluconate 1% flushes for various exposures. In this installment, we will consider the systemic toxicity of HF exposures and the appropriate treatment in those cases.

As HF penetrates deep into the body seeking calcium and magnesium, the exposure can cause significant systemic toxicity secondary to depletion of total body stores of these minerals resulting in cellular death. The majority of deaths in patients experiencing systemic toxicity from HF exposure are the result of cardiac arrhythmias precipitated by hypocalcemia, hypomagnesemia, and other metabolic changes. 

The systemic toxicity that we are discussing can occur in all types of exposures to HF. Inhalation and ingestion exposures would obviously raise concern for the patient but remember that even skin burns from HF can easily cause systemic concerns. Deaths have been reported from concentrated acid burns as little as 2.5% of body surface area or areas of 25 square inches or larger.

One of the signs and symptoms of systemic toxicity can include tetany. Tetany is a symptom that involves involuntary muscle contractions and overly stimulated peripheral nerves. It is caused by electrolyte imbalances, most often low blood calcium levels. Symptoms associated with tetany can include:

• numbness

• spasms of the hands and feet (like the spasms we sometimes see in a patient hyperventilating) 

• twitching of facial muscles

Other severe symptoms can include:

• laryngospasms

• seizures, to name a few

Another symptom of system toxicity from HF can include EKG changes due to electrolyte imbalances. Cardiac monitoring is important to assess for clinically significant electrolyte imbalances. EKG changes that may indicate these imbalances can include prolonged ST segments, QT prolongation, and Torsades de Pointes, to name a few. Be aware that not all these symptoms will be present in all cases of profound hypocalcemia following HF exposure.

Treatment in systemic toxicity is focused on replacing the calcium or magnesium stores in the body. Calcium gluconate at 0.2 to 0.3 ml/kg administered as a slow IV is used to address the calcium deficiencies. If Calcium Gluconate is unavailable, Calcium chloride can manage underlying hypocalcemic effects much like in other emergencies involving calcium deficiencies.  

It is important to note the difference between Calcium Gluconate and Calcium Chloride. Do not confuse these medications. Calcium Chloride is three times higher in concentration and requires different dosing! Providers are encouraged to verify what form of calcium they are provided in their drug boxes and medication supplies and what dosing is recommended for each.

As we end this installment of Pharmacy Phriday, we would point out that today (Dec 16th) is National Ugly Sweater Day. So be on the lookout for the ugliest sweater you have ever seen. And if you do not really care much about sweaters, know that today is also National Chocolate Covered Anything Day! So, consider having some chocolate as well!

Till next time, stay safe!

Sincerely,

The UH EMS-I Team

University Hospitals