ICUNERD

Critical care, from the molecule to the monitor

Understand the why behind every drip, mode, number and rhythm.

ICUNERD is a free study platform for ICU nurses and CCRN® candidates. Every module starts at the receptor, the ion channel, or the pressure–volume loop, then climbs to what you actually do at the bedside — and every claim links to its source.

Start with the four deep dives See the CCRN blueprint map

The first four deep dives

Built from molecular mechanism up to bedside management, with the 2023–2026 literature folded in.

Module 01 · Pharmacology

Vasopressors & Inotropes: A Molecular Architecture

From the G-protein coupled receptor to the titration you chart at 0300: how catecholamines, vasopressin and angiotensin II actually raise a blood pressure, why each one has the side effects it has, and how the 2021–2026 literature reordered the way we stack them.

10 sections10 questions~55 min
Module 02 · Respiratory

Mechanical Ventilation: Modes, Waveforms & Lung Protection

What the ventilator is actually controlling, how to read the four scalars, and why driving pressure and mechanical power have displaced tidal volume alone as the way we think about lung injury — with an interactive waveform simulator and an asynchrony trainer.

10 sections10 questions~60 min
Module 03 · Cardiovascular

Hemodynamics: Delivery, Responsiveness & Congestion

Oxygen delivery versus consumption, the Frank–Starling curve you can actually move, why CVP was replaced by dynamic indices, how to read a PA catheter tracing, and the VExUS grading that turned venous congestion into something you can measure.

10 sections10 questions~60 min
Module 04 · Cardiovascular

EKG: From Ion Channels to Rhythm Interpretation

Start with the sodium channel and the five phases of the action potential, build the vector that a lead actually records, then read rhythms, blocks, axis and ischemia — including the OMI paradigm that is replacing STEMI criteria. With digital calipers you can drag across real-scale strips.

10 sections10 questions~70 min

Mapped to the exam that matters

Everything here is tagged to the AACN Adult CCRN test plan that took effect in November 2025 — 80% Clinical Judgment, 20% Professional Caring & Ethical Practice. Your progress page rolls quiz results up by category so you can see exactly where the points are.

Open the blueprint

Molecular first

Receptors, G-proteins, ion channels and calcium. If you understand why a β1 agonist raises cAMP, you never again have to memorize what dobutamine does.

Cited, not asserted

Guidelines, landmark trials and physiology texts are numbered in-line and listed at the end of each module with links. See the evidence policy.

Interactive by default

Drag a caliper across a rhythm strip. Change PEEP and watch the pressure–time scalar. Slide preload along a Frank–Starling curve. Then take the quiz.

Free. No account.

Progress saves in your browser. No login, no paywall, no ads. Built with the University of Minnesota Atlas of Human Cardiac Anatomy and other open resources.