Approach to the Critical Patient

Airway and hemodynamic priorities

Immediate airway threats

Hemodynamic targets

Severity stratification

Mild hypocalcemia

Moderate hypocalcemia

Severe hypocalcemia

Initial stabilization actions

Time-critical interventions

History

Symptom onset and progression

Neuromuscular symptom timeline

Triggers and precipitants

Surgical history

Physiologic stress triggers

Associated symptoms

Cardiac symptoms

Neuropsychiatric symptoms

Gastrointestinal symptoms

Renal symptoms

Ophthalmologic symptoms

Risk factors and past history

Surgical and medical history

Medication review

Family and genetic history

Family history

Physical Exam

Vital signs and general appearance

Vital sign assessment

Neuromuscular examination

Chvostek sign

Trousseau sign

Spontaneous neuromuscular findings

Airway examination

Laryngospasm assessment

Anterior neck

Dysmorphic and skin findings

Syndrome-specific features

Skin and nails

Eyes

Cataracts

Differential Diagnosis

Life-threatening hypocalcemic causes

Hypoparathyroidism (tetany)

Secondary hypocalcemia

Vitamin D deficiency

Hypomagnesemia

Chronic kidney disease

PTH-resistance syndromes

Pseudohypoparathyroidism

Acute causes of hypocalcemia

Acute pancreatitis

Rhabdomyolysis

Hyperventilation / respiratory alkalosis

Sepsis / critical illness hypocalcemia

Laboratory Tests

Calcium assessment

Serum calcium (albumin-corrected)

Ionized calcium (iCa)

PTH and phosphorus

Intact PTH (iPTH)

Serum phosphorus

Magnesium

Serum magnesium

Vitamin D status

25-OH vitamin D

1,25-dihydroxy vitamin D (calcitriol)

Renal function and monitoring labs

Basic metabolic panel

24-hour urine calcium

Urine calcium-to-creatinine ratio

Diagnostic Tests

Scoring Systems

Hypocalcemia severity classification

Trousseau sign — bedside diagnostic provocative test

Chvostek sign

MRI

Brain MRI in chronic hypoparathyroidism

Spine MRI

CT

CT head (non-contrast)

CT neck post-surgical cases

Ultrasound

Renal ultrasound

Neck ultrasound

Thyroid ultrasound

Point-of-care cardiac ultrasound

Disposition

ICU and telemetry admission

ICU admission criteria

Telemetry/step-down admission

Floor admission

General ward admission criteria

Endocrinology consult for all admissions

Discharge criteria

Safe discharge parameters

Follow-up plan

Treatment

Acute IV calcium replacement

IV calcium gluconate (preferred for peripheral access)

IV calcium chloride (central line only)

Magnesium correction

Hypomagnesemia treatment

Oral calcium and calcitriol initiation

Oral calcium supplementation

Calcitriol (active vitamin D)

Refractory hypocalcemia management

Thiazide diuretics

Optimize vitamin D stores

Phosphate management

PTH replacement therapy

Palopegteriparatide (Yorvipath)

Special Populations

Pregnancy

Physiologic changes in pregnancy

Management modifications

Neonatal considerations

Geriatric

Physiologic considerations

Fall and fracture risk

Polypharmacy considerations

Pediatrics

Neonatal and infant hypocalcemia

Pediatric dosing

Growth and development monitoring

Background

Epidemiology

Prevalence and incidence

Etiology distribution

Pathophysiology

Normal PTH physiology

Consequences of PTH deficiency

Tetany mechanism

Therapeutic Considerations

Treatment targets

Conventional therapy limitations

PTH replacement rationale

Patient Discharge Instructions

copy discharge instructions

What you have been diagnosed with

Your medications at home

Diet instructions

Follow-up plan

Return to emergency department immediately for

References

Guidelines and key sources

Gafni RI, Collins MT. Hypoparathyroidism. New England Journal of Medicine. 2019

Khan S, Khan AA. Hypoparathyroidism: Diagnosis, Management and Emerging Therapies. Nature Reviews Endocrinology. 2025

Clarke BL, Brown EM, Collins MT, et al. Epidemiology and Diagnosis of Hypoparathyroidism. Journal of Clinical Endocrinology and Metabolism. 2016

Orloff LA, Wiseman SM, Bernet VJ, et al. American Thyroid Association Statement on Postoperative Hypoparathyroidism. Thyroid. 2018

Landmark trials and consensus statements

Khan AA, Ali DS, Bilezikian JP, et al. Best Practice Recommendations for Diagnosis and Management of Hypoparathyroidism. Metabolism. 2025

Khan AA, Rubin MR, Schwarz P, et al. PaTHway Phase 3 Trial: Palopegteriparatide in Hypoparathyroidism. Journal of Bone and Mineral Research. 2023

Tsourdi E, Amrein K, Meier C, et al. Consensus-Based Recommendations for Diagnosis, Treatment, and Monitoring of Hypoparathyroidism. Calcified Tissue International. 2025

Shoback DM, Bilezikian JP, Costa AG, et al. Presentation of Hypoparathyroidism: Etiologies and Clinical Features. Journal of Clinical Endocrinology and Metabolism. 2016

Sell J, Ramirez S, Partin M. Parathyroid Disorders. American Family Physician. 2022

Scheuerle AE, Geleske TA, Merchant N, Goldenberg PC. Health Supervision for Children With 22q11.2 Deletion Syndrome. Pediatrics. 2025