ICU Concepts

Vol. I · Adult critical care · For ICU nurses & students

Est. at the bedside · Read anywhere

Critical care, understood by watching it happen.

Most textbooks describe pressures. This one lets you change them. Work through short lessons that ask you to predict first, then show you the circulation answering back — until the numbers on the monitor read like sentences.

Begin with Lesson 1 · Follow the BloodOpen the 3D laboratory

1.

Predict

Commit to an answer before you see the result. Being wrong on purpose is the fastest teacher here.

2.

Watch

See the physiology move — flow, pressures, waveforms — instead of memorising a table.

3.

Apply

Take the same idea to a bedside case with a real patient attached to the numbers.

4.

Return

Missed questions collect in your review queue. Coming back to them is what makes it stick.

Contents

Four units · One circulation

01

Cardiac Hemodynamics

Follow the blood, then learn to read the numbers it leaves behind — flow, filling pressures, resistance, and the four ways the pump fails.

7 lessons · About 40 minutes · Start here

Enter Unit 01
  1. 1.Follow the BloodMap the closed loop of right heart, lungs, left heart, and systemic organs.~4 min
  2. 2.Flow: CO and CISeparate liters per minute from body-size adjusted perfusion.~5 min
  3. 3.Filling Pressures: CVP and PCWPDistinguish pressure from volume and locate CVP and PCWP on the circuit.~5 min
  4. 4.Resistance: SVR and PVRContrast systemic and pulmonary resistance and explore vessel constriction vs dilation.~5 min
  5. 5.Preload, Afterload, and ContractilityManipulate the three primary determinants of stroke volume one at a time.~6 min
  6. 6.Read a Hemodynamic ProfileMaster the 7-step sequence using the Preload → Pump → Pipes → Perfusion framework.~6 min
  7. 7.Apply It to ShockNavigate 5 guided bedside cases: Hypovolemic, Septic, Cardiogenic, RV Failure, and PE.~8 min

02

Bedside Reasoning

Four ICU problems that break four different links of the same circulation. See it, understand it, connect it, act on it, apply it.

4 modules · 5 steps each · Case-based

Enter Unit 02
  1. 01Heart Failure & Pulmonary EdemaCongested, poorly perfused, or both — read the bedside pattern.5 steps
  2. 02Shock & Tissue PerfusionVolume? Pump? Tone? Obstruction? Name the failing link.5 steps
  3. 03Sepsis & Septic ShockInfection plus organ dysfunction — recognize it early.5 steps
  4. 04Disseminated Intravascular CoagulationClotting and bleeding at once — follow the dysregulation.5 steps

03

ECG Rhythm Interpretation

A live monitor sweep and a study library. Learn each rhythm's mechanism, then prove you can name it under time pressure.

16 rhythms · Practice, study & challenge

Enter Unit 03

04

Heart & Hemodynamics Laboratory

The open laboratory: a 3D heart, synchronized waveforms, a pulmonary artery catheter, and room to break physiology on purpose — preload, contractility, resistance, devices.

3D heart · Waveforms · Swan-Ganz simulator

Enter the laboratory

Come back to what you missed

Forgetting is part of the design. Everything you get wrong is kept, with a way back to the exact lesson that teaches it. Clear this queue and the material is yours.

Review queue

Nothing waiting. When you miss a prediction or a rhythm, it will be kept here so you can return to it — that return visit is where the learning actually sticks.

The bedside ruler

Normal values, kept on the contents page where you will actually look for them. Every lesson measures against this ruler.

Cardiac outputCO4.0 – 8.0 L/min
Cardiac indexCI2.5 – 4.0 L/min/m²
Central venous pressureCVP2 – 6 mmHg
Wedge pressurePCWP6 – 12 mmHg
Systemic vascular resistanceSVR800 – 1200 dyn·s/cm⁵
Pulmonary vascular resistancePVR50 – 250 dyn·s/cm⁵
Mean arterial pressureMAP65 – 100 mmHg
Mixed venous saturationSvO₂65 – 75 %

Pressures are not volumes. A stiff ventricle reads high when it is nearly empty — Lesson 3 is built around that single trap.