9.2 Seizures, Nausea, Petechiae & Allergic Reactions

9.2 Seizures, Nausea, Petechiae & Allergic Reactions

Seizures and Convulsions During Venipuncture

Seizures during blood collection are rare but life-threatening emergencies. They can arise from pre-existing seizure disorders (epilepsy), severe metabolic derangements (hypoglycemia), or profound cerebral hypoxia secondary to prolonged, uncorrected syncopal bradycardia (syncopal myoclonus / convulsive syncope).

                  EMERGENCY SEIZURE MANAGEMENT PROTOCOL
  ┌────────────────────────────────────────────────────────────────────────┐
  │ 1. ABORT DRAW IMMEDIATELY                                              │
  │ • Release tourniquet, withdraw needle, activate safety, discard sharps.│
  ├────────────────────────────────────────────────────────────────────────┤
  │ 2. PROTECT PATIENT FROM TRAUMA                                         │
  │ • Cushion patient's head with a folded jacket, towel, or pillow.       │
  │ • Push away phlebotomy trays, sharp objects, tables, and hard items.   │
  ├────────────────────────────────────────────────────────────────────────┤
  │ 3. ABSOLUTE CLINICAL PROHIBITIONS                                      │
  │ • DO NOT restrain convulsing arms or legs (risks fractures/tears).     │
  │ • DO NOT insert tongue depressors, fingers, or objects into mouth.     │
  ├────────────────────────────────────────────────────────────────────────┤
  │ 4. AIRWAY & RECOVERY POSITIONING                                       │
  │ • As soon as possible, gently turn patient onto their side.            │
  │ • Allows vomitus and saliva to drain outward, preventing aspiration.   │
  ├────────────────────────────────────────────────────────────────────────┤
  │ 5. SUMMON MEDICAL AID & TIME DURATION                                  │
  │ • Call Code Blue / Medical Emergency Team / 911 immediately.           │
  │ • Note exact start time and duration of seizure activity.              │
  │ • Monitor post-ictal airway and mental status until help arrives.      │
  └────────────────────────────────────────────────────────────────────────┘

Core Seizure Directives & Prohibitions

• Immediate Needle Removal: The priority is stopping the draw instantly. A needle moving inside an actively convulsing patient can tear brachial blood vessels or sever the median nerve.
• Do Not Restrain Limbs: Phlebotomists must never physically hold down or forcefully restrain a convulsing patient's arms or legs. Forcible restraint against violent involuntary muscular contractions frequently causes muscle tears, joint dislocations (particularly anterior shoulder dislocations), and bone fractures.
• Never Insert Anything Into the Mouth: The historical practice of inserting padded tongue depressors, bite blocks, or fingers between a seizing patient's teeth is strictly contraindicated and dangerous. It causes dental fractures, broken teeth that become aspirated foreign bodies, severe soft-tissue trauma to the tongue and palate, and traumatic bite amputations to the rescuer's fingers. Patients cannot "swallow their tongue"; their airway is protected by positioning them on their side.
• Recovery Position: Turn the patient onto their side (lateral decubitus position) to prevent the tongue from occluding the posterior pharynx and allow secretions or emesis to drain freely from the oral cavity.
• Time the Event: Note the precise start and end time of the seizure. Seizures lasting longer than 5 minutes represent status epilepticus, a medical emergency requiring rapid intravenous anticonvulsant administration by physicians.

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Nausea and Vomiting (Emesis)

Nausea during blood collection is mediated by autonomic vagal stimulation, severe anxiety, or hypoglycemia.

Clinical Management Protocol

1. Stop the Draw: If a patient states they feel sick to their stomach or begins retching, immediately release the tourniquet, withdraw the needle, activate safety, and discard it.
2. Provide Containment: Hand the patient an emesis basin, plastic trash receptacle, or disposable bag. Provide tissues or paper towels.
3. Patient Comfort: Instruct the patient to take slow, deep breaths in through the nose and out through the mouth. Place a cool, damp washcloth on their forehead or the back of their neck.
4. Oral Fluids Restriction: Do not offer water or fluids while the patient is actively nauseated, as this will trigger acute vomiting. Provide a small cup of water for mouth rinsing only after the nausea has fully resolved and the patient is stable.

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Petechiae: Recognition & Clinical Significance

Petechiae are tiny, pinpoint (1 to 2 mm in diameter), non-raised, round, red, purple, or brownish hemorrhagic macules that appear on the skin distal to the tourniquet during or immediately following venipuncture.

+-------------------------------------------------------------------------+
|                     CLINICAL SIGNIFICANCE OF PETECHIAE                  |
+-------------------------------------------------------------------------+
| Definition   | 1–2 mm non-blanching, non-raised red/purple hemorrhagic  |
|              | skin spots caused by capillary micro-extravasation.      |
| Underlying   | • Capillary wall fragility (vascular defect).            |
| Pathology    | • Thrombocytopenia (platelet count < 50,000/µL).         |
|              | • Platelet dysfunction (antiplatelet therapy, uremia).   |
| Phlebotomy   | High risk for excessive, prolonged post-puncture bleeding|
| Impact       | and subcutaneous hematoma formation.                    |
| Mandatory    | Apply continuous, firm direct manual pressure for at     |
| Action       | least 3 to 5 minutes (do not use quick adhesive bandage).|
+-------------------------------------------------------------------------+

Etiology & Pathophysiology

Petechiae occur when the elevated hydrostatic intravascular pressure generated by the tourniquet causes red blood cells to extravasate (leak) through microscopic gaps between endothelial cells in fragile capillary beds. They reflect either:

• Capillary Wall Fragility: Common in elderly patients with senile purpura, chronic corticosteroid therapy, or vasculitis.
• Platelet Defects (Impaired Primary Hemostasis): Severe thrombocytopenia (low platelet count, e.g., in leukemia, chemotherapy, idiopathic thrombocytopenic purpura) or qualitative platelet dysfunction (e.g., aspirin therapy, clopidogrel, von Willebrand disease).

Phlebotomy Precautions for Petechiae

Petechiae are not an allergic reaction and do not require aborting an otherwise uneventful blood draw. However, petechiae serve as a critical warning sign that the patient's primary hemostatic plug formation is compromised.

[!IMPORTANT] Extended Manual Pressure Mandate: When petechiae are observed below the tourniquet, standard 1-to-2-minute post-puncture pressure is insufficient. The phlebotomist must maintain firm, direct manual pressure for at least 3 to 5 full minutes (or until complete hemostasis is visually confirmed) before applying a pressure bandage. Never apply a routine adhesive strip over an actively oozing puncture site.

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Severe Allergic Reactions & Anaphylaxis

Allergic reactions in phlebotomy arise from patient hypersensitivity to collection materials, including natural rubber latex (found in gloves, tourniquets, and bandages), antiseptic agents (chlorhexidine gluconate, povidone-iodine, benzalkonium chloride), or adhesive bandages and tapes.

                  SIGNS OF LIFE-THREATENING ANAPHYLAXIS
  ┌────────────────────────────────────────────────────────────────────────┐
  │ RESPIRATORY: Stridor, severe wheezing, bronchospasm, choking sensation │
  ├────────────────────────────────────────────────────────────────────────┤
  │ INTEGUMENTARY: Facial angioedema (swollen lips/tongue), diffuse hives  │
  ├────────────────────────────────────────────────────────────────────────┤
  │ CARDIOVASCULAR: Severe hypotension, weak thready pulse, loss of consciousness
  ├────────────────────────────────────────────────────────────────────────┤
  │ GASTROINTESTINAL: Severe abdominal cramping, sudden projectile vomiting│
  └────────────────────────────────────────────────────────────────────────┘

Anaphylaxis Emergency Management Protocol

1. Immediate Termination & Allergen Removal: Abort the venipuncture immediately, remove tourniquet, withdraw needle, and strip away any latex gloves, tourniquets, or adhesive dressings from the patient's skin.
2. Call for Immediate Emergency Assistance: Activate the facility Rapid Response Team, dial 911, or call Code Blue. Anaphylaxis progresses rapidly from mild mucosal edema to total airway occlusion and cardiovascular shock within minutes.
3. Patient Positioning & Airway Support: Place the patient in a recumbent position with lower extremities elevated unless severe respiratory distress requires an upright seated posture to facilitate breathing. Continuously monitor airway patency.
4. Prepare for Epinephrine Administration: Intramuscular epinephrine (1:1,000 dilution, 0.3 mg for adults) injected into the anterolateral thigh is the first-line medication for anaphylaxis. The phlebotomist should assist the responding nursing or medical team by retrieving the emergency anaphylaxis kit or automated epinephrine injector.