UCSD Musculoskeletal Radiology

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Drug Treatment in Emergencies

Drug Treatment in Emergencies

Contrast Media Reactions

 

Types - Physiologic (non-idiosyncratic)

Common -warmth

-flushing

-nausea

-metallic taste

Uncommon -seizures

-cardiac depression

-arrhythmias

-renal damage

-increased airway resistance

(physiologic reactions are dependent on concentration and dose of contrast material)

- Non-Physiologic (idiosyncratic) -anaphylactic reactions

mild

moderate

                                                            severe (0.01%)

            -vaso-vagal reactions

 

Those at increased risk for anaphylactic reactions

- previous reaction (>5 times increased risk)

- asthma (2-5 times)

- multiple allergies (2 times)

- renal and cardiac disease

 

Relative Contraindications

- previous moderate or severe reaction

- diseases: phaeochromocytoma (hypertensive crisis)

multiple myeloma (renal failure)

sickle cell anaemia (sickle cell crisis)

poorly controlled hyperthyroidism (thyroid storm)

renal failure, esp. IDDM (contrast induced renal failure)

myasthenia gravis (acute exacerbation)

NIDDM treated with metformin/glucophage (lactic acidosis)

 

Pre-assessment

- prior contrast administration and any reaction

- allergies (food or drug)

- medical history - co-existing diseases and drug therapy

- latex allergy

- calculate paediatric dosage of adrenaline prior to contrast administration

 

 

Assessing the Reacting Patient

 

Visual

- uncomfortable

- anxious / agitated

- unresponsive

- respiratory pattern

- skin

 

Call for assistance

 

Vital signs

- Pulse

- Blood pressure

- Respiratory rate

 

May begin as:

- nausea

- vomiting

- chills

- fever

- sneezing

- "feeling peculiar"

- watery or red eyes

- nasal congestion

- abdominal pain

- confusion I disorientation I heightened anxiety

 

Specific Manifestations

 

 

General Treatment Principles

Drugs

- The contents of emergency boxes and trolleys may include:

Adrenaline inj. 1/1000 & 1/10000

Atropine sulphate inj. 0.6mglml

Hydrocortisone (Solu-Cortef) inj. 100mg/ 2ml

Phenergan (promethazine) inj. & tabs. 25mg

Aminophylline inj. 250mg/10ml

Lignocaine 1% inj.

Water for injection

Saline for injection

Saline bag & infusion kit

Sodium bicarbonate inj.

Nitrolingual spray

Ventolin inhaler

Anexate (flumazenil) 0.5mg/5ml

Narcan (naloxone) 0.4mg/ml

Adalat (nifedipine) caps.

Frusemide inj. 10mg/ml

 

Equipment

- i.v. cannulae

- drip sets

- needles and syringes

- airways

- Ambu-bag or equivalent

- Suction

- Sphygmomanometer

- Pulse oximeter

- Defibrillator (know where kept and how accessed for each site)

 

Oxygen

- high dose oxygen (10-12 l/min) via face mask

- any patient in respiratory distress

 

Adrenaline

- The single most important medication in the treatment of anaphylactic reactions

- Particularly effective in reversing respiratory manifestations of moderate or severe reactions as well as in treating cardiac arrest

            1:10,000 1mg/10ml, 10mI - intravenous, 1 to 3ml slow Iv, total dose of 10 mI in cardiac arrest

- calculate paediatric dose prior to contrast administration

 

Corticosteroids

- no acute role

- may be effective in reducing delayed recurrent symptoms which may occur up to 48 hours

- 100 to 1000 mg hydrocortisone iv

- initial dose can be followed by a continuous infusion

 

Personnel Training and Availability

- basic life support techniques

 

Cutaneous reactions

-Hives -no treatment needed for most

-when itchy or bothersome: Phenergan 25mg po/im/iv

-can produce drowsiness

-rarely large and patients extremely uncomfortable:

can be treated with iv H2 blockers (Ranitidine) if Phenergan does not relieve

-Erythema or cutaneous/subcutaneous oedema (angio-oedema)

-careful monitoring to ensure severe manifestations don't develop (hypotension, airway oedema)

-monitor vital signs

-treatment as for hives or even Adrenaline

 

Respiratorv reactions

- Upper airway/laryngeal oedema:

-treat with Oxygen and Adrenaline

- Bronchospasm:

-treat with Ventolin inhaler and oxygen,

-Adrenaline

-Aminophylline 5mg/kg diluted in D5W over 10-20min iv (most around 250mg)

- Pulmonary oedema:

-elevate head

-Oxygen

-Frusemide 4Omg iv

- Anxiety:

-diagnosis of exclusion

-no specific treatment

-paper bag for hyperventilation

-rarely Hypnovel

 

Chest Pain

- Angina:

-retrosternal discomfort

-may radiate to back or shoulders, left arm or neck

-Oxygen, sublingual nitroglycerin, Nitrolingual spray

- Dyspnoea:

-as for respiratory reactions

 

Hypotensive reactions

- systolic BP < 90mmHg

- if unresponsive call cardiac arrest team

- high dose Oxygen

- elevate legs

- saline infusion (rapid, can squeeze bag)

- if bradycardic (P < 60) = vasovagal

-treated with Atropine 0.6 - 1mg iv

-can be repeated every 3 - 5 minutes

- hypotension + tachycardia = anaphylaxis

The Unresponsive Patient

- call help / cardiac arrest

- CPR

Delayed reactions (including Fever & Chills)

- occur from 1 hour to 3 days

- include: -fever/chills/rigors

-rash

-flushing

-dizziness

  • -pruritis
  • -arthralgias

    -diarrhoea

    -nausea & vomiting

    -headache

    - rarely: -acute parotitis (iodide mumps)

    - treatment generally supportive

     

    Seizures

    - turn on side, recovery position +/- suction

    - is seizure due to hypoxia? i.e. hypotension

    - if normal vital signs = neurogenic

    - give Oxygen

    - if severe 5mg Diazepam or 2.5mg Hypnovel slowly iv

     

    Hypertensive Crises

    - diastolic BP > l2OmmHg

    - Oxygen

    - sublingual nitroglycerin

    - Nifedipine 10mg sublingual

     

    Extravasation of Contrast Material

    - cold compress

    - elevation

    - follow until symptoms resolve

     

    NB: Patients who have had mild reactions should be observed for at least 30 minutes

     

    Reference: Cohan et al: Treatment of Adverse Reactions to Radiographic Contrast Media in Adults

    RCNA - vol 34, number 5, Sept.1996, pp1O55-1076