EM@3AM: Hiccups

Author: Christopher J. Nelson, MD (EM Resident Physician, UTSW, Dallas, TX) // Reviewed by: Alex Koyfman, MD (@EMHighAK); Brit Long, MD (@long_brit)

Welcome to EM@3AM, an emDOCs series designed to foster your working knowledge by providing an expedited review of clinical basics. We’ll keep it short, while you keep that EM brain sharp.

Answer: Intractable Hiccups

Background:

• Hiccups are also known as hiccoughs or singultus
• Hiccups are the involuntary/synchronous spasm of the diaphragm/intercostal muscles resulting in sudden inspiration and glottic closure leading to the well-known “hic” sound¹
• Commonly thought to be related to phrenic, vagal, and sympathetic nerve arcs, although other etiologies must be considered²
• Central causes are thought to stem from hypothalamic and medullary respiratory centers²
• May occur as high as 100 times per minute even during sleep leading to significant distress

• Hiccup Bout: Less than 48 hours
• Persistent Hiccups: 48 hours to 1 month
• Intractable Hiccups: Greater than 1 month³

Epidemiology:

• Found in numerous mammalian species⁴
• Almost all experience hiccups at some point during life
• Intractable hiccups found to be male dominant in non-CNS causes with an odds ratio of 2.42⁵
• Younger ages affected more commonly in females⁵
• Less likely organic cause in children and full team infants⁴
• Studies have not shown racial or socioeconomical trends^4,5

Assessment:

• Assess time of onset, duration, frequency, relieving/exacerbating factors
• Medical history that increases risk of intractable hiccups – Cancer, AIDS, recent weight loss, dysphagia, GERD, blunt trauma²
• Medications than lead to hiccups – Chemotherapeutic agents, benzodiazepines, corticosteroids⁶
• Surgical – Recent surgery/procedure (HEENT, chest, abdomen), as well as intubation
• Review of symptoms and exam
  • ENT
    • Throat/chest burning/GERD symptoms, difficulty swallowing
    • Ear canal exam⁷
  • Cardiac – Hiccups can be an atypical symptom of ACS⁸
    • Chest pain, SOB, numbness, tingling, epigastric pain, nausea, vomiting
  • Neurologic – Consider infarct
    • CN II-XII, cerebellar testing (finger-to-nose, heel-to-shin), ambulation, strength, sensation, reflexes

Hiccups Differential Diagnosis:

• Central Nervous System
  • Stroke, tumors, injury, seizure
• Cardiac
  • ACS
• GI
  • Gastroesophageal reflux disease, esophageal tumors
• Drugs
  • Chemotherapeutic agents, steroids, psychiatric medications
• Electrolyte abnormality
  • Hyponatremia, hypokalemia
• Procedures
  • Intubation, bronchoscopy, esophagogastroduodenoscopy, central venous catheter
• Miscellaneous
  • Cancer, EtOH use
• Toxin mediated

Clinical Presentation:

• This is a clinical diagnosis
• Sudden feeling of involuntary diaphragm contractions and inspiration followed by pause in breath and classic “hic” sound
• Typically ranging from 30-100 hiccups per minute
• Normally self-resolving by 48 hours of onset without intervention
• Considered persistent if greater than 48 hours and intractable if greater than 1 month³
• Persistence during sleep may suggest organic cause⁹

Evaluation:

• Generally conservative unless history or physical suggest otherwise
• External auditory canal exam for foreign body or hair against tympanic membrane⁷
• CMP – Sodium most common electrolyte culprit¹⁰
• CBC – If infection suspected
• Less common labs but considered in the right clinical context
  • EtOH, Lipase, UA, CSF studies
• Consider CXR for mass vs. structural abnormality
• Consider evaluation for cardiac cause with ECG, CXR, troponin, BNP
• CNS imaging as directed by history and exam – CT head vs. CTA head/neck vs. MR brain

Treatment:

• Conservative treatment typically involves glottic stimulation/manipulation
  • Breath holding
  • Large gulps of water
  • Drinking water upside-down
  • Vagal maneuvers
  • Pharyngeal vs. nasopharyngeal stimulation with nasopharyngeal tube or foley¹¹
• Pharmacologic – Reserved for symptoms greater than 48 hours
  • PPI – Often first line, GERD treatment
    • Omeprazole 20 mg daily¹²
    • Pantoprazole 40 mg daily¹²
  • Other medications – similar in efficacy with varying side effect profiles
    • Metoclopramide: 10 mg IV/IM; 10–20 mg PO TID x 10 days¹³
    • Chlorpromazine: 25-50 mg IV in 500-1000 mL NS over at least 1 hour, 25 mg QID, increase to 50 mg if needed⁴
      • Only medication FDA approved for hiccups⁷
    • Gabapentin: 300 mg TID¹⁴
    • Baclofen: 5 mg BID to 20 mg TID^15,16
  • Less commonly cited treatment
    • Haloperidol: 2-5 mg IM vs. PO, can continue 1-4 mg TID PO⁴

Disposition:

• Discharge uncomplicated cases, able to tolerate PO
• If complex secondary cause is identified such as stroke, mass, etc., admission may be required

Pearls:

• Hiccups are common
• Defined as intractable when persistent for greater than 48 hours
• Do not miss organic causes: cardiac, neurologic, electrolyte, toxic ingestion/exposure, structural, cancer
• Conservative treatment first, pharmacologic second line
• No clear first-line drug choice
  • Consider case-by-case and side-effect profiles