The systems-based approach

One of the idiosyncrasies of critical care is the practice of breaking down each patient by systems.

Most specialties document the review of systems and physical examination in this manner, organizing the large quantity of resulting data into categories such as “Cardiovascular,” “Respiratory,” and “Musculoskeletal.” Only critical care, however, tends to present its assessments and plans in the same style.

Why? Simply put, critically ill patients are complicated. A typical ward patient may be admitted with only one or two problems that need addressing. In contradistinction, an ICU patient usually has one or two primary, driving problems—but also a host of other concomitant issues that complicate or emerge from them, such as mechanical ventilation, stress ulcer prophylaxis, and electrolyte abnormalities. This litany of mentionables would quickly lead to an unwieldy “problem-based” assessment and plan, but it’s worse than that: without a universal framework to make sure you address every angle of a multi-faceted patients, it’s easy to miss things. Rather than only considering whatever problems spring to mind, you need a set of standard categories that forces you think comprehensively.

A systems-based approach is the flexible Swiss Army Knife of critical care. When applied regularly and consistently, it becomes ingrained into one’s very mental model of the patient, like a medical Sapir-Whorf hypothesis. More mundanely, it can be invoked when writing notes, rounding, presenting a patient, or signing them out.

How does it work? There are many variations on the theme, and it can be adjusted for your needs. Different folks list different systems, and certainly place them in differing orders; indeed, it is de rigueur to give one’s favorite system primacy, so the CCU tends to place Cardiovascular first, the MICU starts with Respiratory, and the NCCU favors Neurologic. It hardly matters, but develop your own preferences, and keep it consistent; that way you’ll be able to activate your personal template from memory without a second thought.

Here’s an approach to get you started.


  • Pain, analgesia, and sedation (although some prefer to make a separate category for this)
  • Encephalopathy of any variety, including delirium
  • Neurological injuries
  • Mobilization and activity


  • Shock, pressors, and inotropes
  • Arrhythmias
  • Heart failure
  • Acute coronary syndromes and troponinemia


  • Respiratory failure
  • Mechanical and non-invasive ventilation, including extubation plans
  • Pneumonitis and pneumonia
  • ARDS
  • Pneumothorax, COPD, asthma, etc.
  • Pulmonary toileting (e.g. incentive spirometry) and SpO2 goals


  • Diet, enteral feeding, TPN—or NPO status
  • Stooling issues such as diarrhea or constipation, and bowel regimens
  • GI bleeds or surgical issues involving the GI tract (ostomies, bowel trauma), and hardware (NG tubes, PEGs, rectal tubes)
  • Hepatic pathology such as transaminitis, cholecystitis, and cirrhosis
  • Stress ulcer prophylaxis, if not mentioned elsewhere


  • Fluids, including fluid balance issues (e.g. overload and diuresis), IV fluids, and urine output
  • Electrolytes, including imbalances worth mentioning. (Note: some providers like to make a separate “FEN” category that lumps together Fluids, Electrolytes, and Nutrition.)
  • Acid-base issues, such as metabolic acidosis
  • Renal and GU pathology such as hematuria, renal calculi, and most commonly, acute kidney injury


  • Cell line dyscrasias, including anemia, thrombocytosis, and thrombocytopenia
  • Coagulopathies, such as DIC
  • Bleeding issues, although these can sometimes fall into other categories as well
  • Thrombosis, such as DVT and PE. DVT prophylaxis can be discussed here if not placed elsewhere


  • Glucose control
  • Thyroid derangements, adrenal insufficiency, and other hormonal imbalances

Infectious Disease

  • Active infections, either suspected (leukocytosis, etc) or proven
  • Microbiology results: blood/sputum/urine cultures, gram stains, lab assays (C difficile PCRs, Legionella urinary antigen, etc.)
  • Antibiotics: current, prior, and planned durations

Other things

Depending on the clinical setting and provider preference, other “systems” may be useful to include. These might include Trauma, Surgical, Musculoskeletal, or Orthopedic. Some like an Integumentary or Skin system.

Systems where nothing needs to be said can simply be documented with a remark such as “No active issues.”

In addition to the above, some non-physiologic but practical categories are often worth establishing, such as:

  • Prophylaxis: DVT and stress ulcer prophylaxis.
  • Access: Current intravenous access, such as peripheral IVs, central lines, and arterial lines. This can also be expanded to a list of all lines/tubes and other hardware, such as chest tubes, Foleys, drains, etc. It is also wise to document when such things were placed, and whether or not it was sterile.
  • Social: Social issues, such as the name and contact information for the primary decision-maker, or family conflict and other dilemmas.
  • Finally, it is common to end with the ultimate question: Disposition. Where will the patient go? Will they stay in the ICU, be downgraded to another service, or even be discharged?

Worth the while

While this approach to patient care may seem obsessively thorough, it is thoroughness—rather than the excitement of resuscitation or the bloody drama of procedures—that may be the truest hallmark of critical care.

Certainly, there are providers, or whole teams, whose practice and culture do not cleave to this method. They round haphazardly, identifying whichever problems catch their eye and addressing them ad hoc. In their notes, they mention only the most noticeable issues and omit the others. When presenting a patient they only discuss the immediate.

Their approach saves time. It saves time by forgetting important things. And that is not good critical care.

2 Replies to “The systems-based approach”

Leave a Reply

Your email address will not be published. Required fields are marked *