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Summary

Critically ill patients are typically cared for in intensive care units (ICUs), which are designated hospital units dedicated to managing patients who require a higher level of care than that available on a general medical ward or step down unit, staffed by highly trained clinicians. After initial resuscitation and stabilization, management of ICU patients typically involves ongoing hemodynamic monitoring (often via invasive devices such as an arterial line) and respiratory monitoring (including interpretation of ventilator alarms for mechanically ventilated patients), supportive care of the critically ill patient (including nutrition and metabolic support, analgesia, and sedation), and the prevention of common complications (e.g., VTEs, pressure ulcers, nosocomial infections, delirium). Predictive scoring systems (e.g., the SOFA score, APACHE II score) may be useful for the prognostication of ICU patients. Given the critical nature of ICU care, teamwork and communication, and end-of-life care are essential. Typical reasons for admission to an ICU include the need for organ support (e.g., for patients with brain injury, acute coronary syndrome, COPD exacerbation, sepsis, GI bleeding) and/or close, continuous monitoring (e.g., postoperatively or while receiving a high-risk medication).

Definitions

  • Critical illness: a state of poor health with vital organ dysfunction and/or imminent death [2]
  • Critical care: provision of medical care to critically ill patients by supporting vital organ function [2]
  • Intensive care units
    • Units that provide the highest level of care available in a hospital
      • Can be open or closed
      • Can be general medical or surgical, or specialized units (e.g., neurological, cardiac)
    • Indicated for patients who require close or continuous monitoring:
      • While receiving (or in imminent need of) organ support: e.g., mechanical ventilation, vasopressors, extracorporeal therapies
      • During treatment for severe illness, often with continuous IV infusions (see “Common conditions treated in the ICU”)
      • Immediately post-surgery or post-procedure
  • Intermediate care units: units that provide a higher level of care than a general ward but a lower level of care than an ICU

There are no established general criteria for ICU admission. The decision to admit a patient typically relies on the clinical judgment of the physician and the availability of beds and resources.

Resuscitation and stabilization

The first step in caring for critically ill patients is resuscitation and stabilization. See also “ABCDE approach” for more detail.

Hemodynamic support

  • Establish a route of access for parenteral fluid therapy and medications.
  • Provide advanced cardiac life support if cardiac arrest is present.
  • Evaluate and treat for any clinical features of shock.
    • Provide immediate hemodynamic support for undifferentiated shock.
    • Perform appropriate diagnostics in shock.
    • Consider mechanical circulatory support in patients with refractory cardiogenic shock.
  • Evaluate and treat any arrhythmias.
    • Management of tachycardia
    • Management of bradycardia

Respiratory support

See also “Management of respiratory failure.”

  • Identify airway obstruction and perform basic airway maneuvers.
  • Start oxygen therapy (if applicable) via one of the following:
    • Basic oxygen delivery systems
    • High-flow nasal cannula
    • Noninvasive positive-pressure ventilation
  • If indications for invasive mechanical ventilation are present:
    • Prepare for and perform endotracheal intubation.
    • Start invasive mechanical ventilation.
      • Select the appropriate ventilator settings and ventilator strategies.
      • Start sedation (see “Adjunctive care of the ventilated patient”).
    • Anticipate and manage complications of intubation.

Extracorporeal membrane oxygenation (ECMO)

  • Consider use in patients who require advanced respiratory and/or circulatory support
  • VA-ECMO: provides respiratory and circulatory support
  • VV-ECMO: provides respiratory support only

Monitoring parameters

All critically ill patients require close monitoring of hemodynamic and respiratory status.

Hemodynamic monitoring

  • Follow relevant monitoring parameters for parenteral fluid therapy.
  • Follow relevant monitoring parameters for patients with shock.

Invasive devices

  • Arterial line: used to accurately measure blood pressure
  • Central venous catheter : used to measure central venous pressure
  • Pulmonary artery catheterization
    • Not routinely recommended for hemodynamic monitoring
    • Consider for specific cases, including: [3][4]
      • Refractory shock: especially in patients with ARDS or right ventricular dysfunction
      • Undifferentiated shock: especially if there is uncertainty about the fluid status of patients at very high risk of pulmonary edema

Routine pulmonary artery catheterization for hemodynamic monitoring has not been shown to improve outcomes in critically ill patients with shock and, therefore, should only be used in specific cases. [3][4]

Respiratory monitoring

  • Conduct appropriate monitoring of mechanically ventilated patients.
  • For patients who are deteriorating (or in respiratory distress), simultaneously: [5]
    • Conduct initial maneuvers ; see also “Troubleshooting of mechanical ventilation.”
    • Try to identify the underlying cause: See “Interpretation of ventilator alarms.”

Consider using the DOTTS mnemonic to remember the interventions in a mechanically ventilated patient who is deteriorating: Disconnect, Oxygenate, assess the Tube position and function, Tweak ventilator settings, and perform a chest Sonogram (e.g., to identify pneumothorax). [5]

Supportive care

Management should be individualized for each patient, but there are some common features of supportive care in critically ill patients.

Critically ill patients need FAST HUGS DAILy: every day, evaluate their Feeding and fluids, Analgesia, Sedation, Thromboembolic prevention, Head of the bed elevation, Ulcer prophylaxis, Glucose control, Skin pressure ulcer prophylaxis, Deescalation of drugs, Assessment of delirium, Indwelling catheters, Last bowel movement. [6]

Nutrition and metabolic support of critically ill patients [6][7][8]

  • Specialized nutrition support (when oral intake is not possible)
    • Start within 24–48 hours of ICU admission.
    • Can be enteral nutrition (preferred) or parenteral nutrition
  • IV fluid therapy
    • Adjust strategies for parenteral fluid therapy based on the patient's needs.
    • Monitor and evaluate parenteral fluid therapy daily.
  • Metabolic support
    • Glycemic control:
      • Provide inpatient management of hyperglycemia. [9]
      • Treat hypoglycemia, if present.
    • Provide electrolyte repletion.
    • Consider the need for stress-dose steroids to prevent acute adrenal insufficiency (i.e., critical illness-related corticosteroid insufficiency).

Enteral nutrition is associated with fewer metabolic complications and bloodstream infections and better patient outcomes compared to parenteral nutrition. [6]

Pain management in critically ill patients [10]

  • Evaluate pain using validated scales such as:
    • Behavioral pain scale
    • Critical care pain observation tool
  • Individualize the acute pain management approach.
    • Timing: e.g., continuous infusions or interval dosing [11][12]
    • Pain type: e.g., nociceptive pain, neuropathic pain.
    • Contraindications and adverse effects

Sedation [8][10]

  • Choose an appropriate agent: For agents and dosages, see “Adjunctive care of the ventilated patient.”
  • Monitor sedation levels. [8]
    • Use the Richmond Agitation-Sedation Scale (RASS).
    • Light sedation is generally recommended instead of deeper sedation . [10]
    • For mechanically ventilated patients: See “Adjunctive care of ventilated patients”
  • Reevaluate sedation indications: Consider regular breaks from sedation. [8]
    • Spontaneous awakening trials
    • Spontaneous breathing trials

Prevention of complications [6][7][8]

Prevention of complications is paramount to minimizing harm and improving outcomes.

Prevention of complications in ICU patients
Complication Prevention strategy
VTE prophylaxis
  • Patients with high bleeding risk: mechanical VTE prophylaxis
  • Patients without high bleeding risk: pharmacological VTE prophylaxis
Stress ulcer prophylaxis
  • Consider for all patients at risk of GI bleeding.
  • Tailor the intervention based on the risk of GI bleeding.
  • See also “Indications for stress ulcer prophylaxis.”
Decubitus ulcer prophylaxis
  • Prevent and treat decubitus ulcers for all patients [13][14]
  • Interventions may include:
    • Change the patient's position every 2 hours.
    • Use an alternating pressure mattress.
    • Mobilize patients early.
Nosocomial infections
  • Examine lines, tubes, and catheters daily: Reassess indications and consider changing or discontinuing them as appropriate.
  • Initiate measures for:
    • Prevention of catheter-associated urinary tract infections
    • Prevention of intravascular catheter-related infections
    • Prevention of ventilator-associated infections
      • Elevate the head of the bed to 45°.
      • Determine appropriate timing for ventilator weaning and perform spontaneous breathing trials.
Delirium
  • Screen regularly for delirium with the adapted confusion assessment method intensive care unit tool (CAM-ICU tool).
  • If delirium is present:
    • Symptom-based diagnostic workup for delirium
    • Treat any precipitant factors (e.g., modify any deliriogenic medications).
    • Identify the patient's needs and establish a patient-centered treatment plan
    • See also “Acute management checklist for delirium.”
Medication adverse effects
  • Reassess the need for each drug.
  • Avoid nephrotoxic substances for the prevention of acute kidney injury.
  • Avoid hepatotoxic medications to prevent drug-induced liver injury.
  • Deescalate and discontinue treatment as indicated
ICU-acquired weakness
  • Consult physical therapy and occupational therapy as early as possible.
  • Mobilize patients as early as possible.

Prevent delirium in critically ill patients using the ABCDEF bundle: Assessment of pain, Both spontaneous awakening trials and spontaneous breathing trials, Choice of analgesia and sedation, Delirium screening, Early mobilization, Family engagement. [8]

The use of lorazepam or diazepam for sedation may cause iatrogenic propylene glycol poisoning, as both drugs are dissolved in propylene glycol. Midazolam is an alternative benzodiazepine that does not use propylene glycol as a solvent. [15]

Predictive scoring systems

Scoring systems can give a general sense of prognosis but they should not be the sole factor used to determine the level of care required or if a patient should be moved to a lower level of care.

Sequential organ failure assessment score (SOFA score) [16][17]

  • Used in critical care settings as a tool to identify organ failure and predict mortality
  • The score should be calculated 24 hours after ICU admission and then every 48 hours.
  • Commonly used to assess mortality risk in patients with sepsis
SOFA score [16][18]
System 0 points 1 point 2 points 3 points 4 points
Respiration PaO2:FiO2 ratio (mm Hg)
  • ≥ 400
  • ≤ 400
  • ≤ 300
  • ≤ 200 with respiratory support
  • ≤ 100 with respiratory support
Coagulation Platelets (x 1000/mm3)
  • > 150
  • ≤ 150
  • ≤ 100
  • ≤ 50
  • ≤ 20
Liver Bilirubin (mg/dL)
  • < 1.2
  • 1.2–1.9
  • 2.0–5.9
  • 6.0–11.9
  • ≥ 12.0
Cardiovascular
  • MAP ≥ 70 mm Hg
  • MAP < 70 mm Hg
  • Dopamine ≤ 5.0 mcg/kg/min for ≥ 1 hour
  • OR dobutamine at any dose
  • Dopamine 5.1–15 mcg/kg/min for ≥ 1 hour
  • OR epinephrine ≤ 0.1 mcg/kg/min for ≥ 1 hour
  • OR norepinephrine ≤ 0.1 mcg/kg/min for ≥ 1 hour
  • Dopamine > 15 mcg/kg/min for ≥ 1 hour
  • OR epinephrine > 0.1 mcg/kg/min for ≥ 1 hour
  • OR norepinephrine > 0.1 mcg/kg/min for ≥ 1 hour
Central nervous system Glasgow coma scale score
  • 15
  • 13–14
  • 10–12
  • 6–9
  • < 6
Renal function Creatinine (mg/dL)
  • 1.2 mg/dL
  • 1.2–1.9 mg/dL
  • 2.0–3.4
  • 3.5–4.9
  • OR urine output < 500 mL/day
  • ≥ 5.0
  • OR urine output < 200 mL/day
Interpretation
  • SOFA score ≥ 2 points: overall mortality risk ∼ 10%

Acute physiology and chronic health evaluation II (APACHE II score)

The APACHE II score should be calculated within the first 24 hours of ICU admission. [19][20]

  • Components
    • Physiological score
    • Age score
    • Chronic health score
  • Result: an estimate of the patient's in-hospital mortality risk
  • Potential limitations
    • Generalizability
    • Accuracy

Additional scoring systems for specific conditions

Commonly used scoring systems for specific conditions include:

  • Pneumonia: PSI/PORT score (estimates mortality risk)
  • Pancreatitis: Ranson criteria (estimates mortality risk)
  • Cirrhosis: MELD score, Child-Pugh score (estimate mortality risk)
  • Upper GI bleeding: Glasgow-Blatchford bleeding score (estimates risk of requiring intervention)

End-of-life considerations

End-of-life considerations should be addressed for all patients upon admission to the ICU. Essential tasks include establishing a decision-maker, confirming advance directives, and considering the need for a palliative care consult.

  • Decision-making
    • Evaluate the decision-making capacity and legal competence of the patient.
    • Identify an appropriate surrogate decision-maker, if necessary.
    • Confirm advance directives regarding all end-of-life care for the patient.
  • Palliative care
    • Provide appropriate palliative pain control.
    • Other management as necessary, e.g.:
      • Palliative pharmacotherapy for dyspnea
      • Management of delirium in palliative care
      • Palliative anxiolysis
  • Death and dying
    • Follow recommendations for the management of imminently dying patients.
    • Follow the process for pronouncing death or brain death (if relevant).
    • Document patient death (adhere to institutional protocols).
      • Determine whether the situation falls under reportable types of death.
      • Confirm plans for an autopsy.

Addressing family and friends after death should be prioritized.

Teamwork and communication

An essential part of ICU care is ensuring appropriate communication with the following people. See also “Key principles of communication and counseling.”

  • Patients and family:
    • Update the patient's family regularly (by phone if the family are not at the bedside).
    • Communicate in an empathic, patient-centered way.
    • Elicit the patient's and family's needs and wants.
    • See also “Breaking bad news.”
  • Nonphysician team members: See “Communicating with nonphysician team members.”
  • Other physicians
    • Update consultants and other team physicians regularly throughout the day.
    • If a patient begins to deteriorate, do not hesitate to request help immediately.
    • Ensure you provide a focused and constructive signout.

Common conditions treated in the ICU

Common ICU conditions by system
System Management
Neurological
  • Management of alcohol withdrawal
  • Management of ischemic stroke (see also “Acute management checklist for ischemic stroke”)
  • Management of status epilepticus
  • Brain injury
    • Intracranial pressure management
    • Management of moderate and severe TBI
    • Secondary brain injury and neuroprotective measures
    • Management of brain death
Cardiovascular
  • Postresuscitation care
  • Management of acute heart failure (see also “Acute management checklist for heart failure exacerbation”)
  • Management of hypertensive crisis (see also “Acute management checklist for hypertensive crisis”)
  • Acute coronary syndromes
    • Management of STEMI (see also “Acute management checklist for STEMI”)
    • Management of NSTEMI/UA (see also “Acute management checklist for NSTEMI/UA”)
  • Arrhythmias
    • Management of atrial fibrillation (see also “Acute management checklist for atrial fibrillation”)
    • Management of atrial fibrillation with RVR
Pulmonary
  • Management of acute asthma exacerbation (see also “Acute management checklist for asthma exacerbation”)
  • Management of COPD exacerbation (see also “Acute management checklist for COPD exacerbation”)
  • Management of pulmonary embolism (see also “Acute management checklist for pulmonary embolism”)
  • Management of ARDS (see also “Acute management checklist for ARDS”)
Infectious disease
  • Management of pneumonia (see also “Acute management checklist for pneumonia”)
  • Management of sepsis (see also “Acute management checklist for sepsis”)
  • Nosocomial infections (e.g., intravascular catheter-related bloodstream infections, Clostridioides difficile infection)
  • See “Management of hospitalized patients” in “COVID-19.”
Gastrointestinal
  • Management of acute pancreatitis (see also “Acute management checklist for pancreatitis”)
  • Management of acute liver failure
  • Management of cirrhosis
  • Management of gastrointestinal bleeding
Renal
  • Workup and management of acid-base disorders (see “Diagnostics” in “Acid-base disorders”)
  • Management of acute kidney injury (see also “Acute management checklist for AKI”)
Endocrine
  • Management of hyperglycemic crises (see also “Acute management checklist for hyperglycemic crises”)
  • Adrenal insufficiency
    • See “Management” in “Adrenal crisis” (see also “Acute management checklist for adrenal crisis”)
    • Management of critical illness-related corticosteroid insufficiency
  • Management of thyroid storm (see also “Acute management checklist for thyroid storm”)
Hematologic
  • Anemia
    • Anemia workup
    • See “Acute management checklist for anemia.”
  • Platelet disorders
    • Management of heparin-induced thrombocytopenia (see also “Acute management checklist for HIT”)
    • Management of disseminated intravascular coagulation (see also “Acute management checklist for DIC”)
    • Management of thrombotic thrombocytopenic purpura
  • Management of acute chest syndrome (see also “Acute management checklist for acute chest syndrome”)
  • See “Transfusion.”
  • Anticoagulant reversal (see also “Acute management checklist for anticoagulant reversal”)
Oncologic
  • See “Oncologic emergencies.”
  • Management of neutropenic fever (see also “Acute management checklist for neutropenic fever”)

Management checklists

This section provides checklists for managing the major aspects of patient care over the course of an ICU admission. The following checklists may serve as general guidance but may not be applicable to all patients and/or settings; follow institutional protocols.

Admission checklist

  • Review electronic medical records for the following (before admission if possible):
    • Medical history and current medication list
    • Emergency department course
    • Microbiology
    • Previous advance directives
  • Immediately upon admission:
    • Note current vital signs.
    • Resuscitate and stabilize the patient as necessary.
    • Place any urgent orders.
  • Perform a focused history and examination. If the patient has the capacity:
    • Confirm home medications.
    • Address end-of-life considerations (see “End-of-life considerations” in “General principles of ICU care”).
    • Ask for permission to update a family member and obtain relevant contact information.
  • Place admission orders.
    • Perform thorough medication reconciliation.
    • Use standard admission order sets.
    • Include any laboratory studies and/or imaging to be performed overnight or the next morning.
  • Write an admission note and make sure to document the following:
    • General prognostic score (e.g., APACHE II, SOFA score)
    • Scores relevant to the patient's reason for admission (e.g., PSI for pneumonia)
    • Wishes regarding advance directives (and complete any relevant forms)
  • Update family members if appropriate.
  • Update signout template (see “Signout checklist”).

Daily care checklist

  • Obtain signout from the overnight resident.
  • Review the following:
    • New recommendations from consultants
    • Overnight events and orders placed
    • Vital signs
    • Intake-output monitoring over the past 24 hours
    • Laboratory studies and microbiology
    • Imaging
    • Telemetry (if applicable)
  • Assess the patient at the bedside.
    • Check monitors and note current vital signs and ventilator settings.
    • Perform a focused examination, including an assessment of:
      • Neurological status (e.g., RASS score, pupils, reflexes)
      • Volume status
    • Check all current lines, tubes, and catheters.
    • Check the rate of all current IV infusions.
  • Coordinate with respiratory therapy and nurses to perform a spontaneous breathing trial or spontaneous awakening trial if appropriate.
  • Check and place orders for supportive care of the critically ill patient.
  • Update the patient's family (by phone if not present at the bedside).
  • Update signout template.

Signout checklist

Due to the complexity of ICU patients, a signout template with the following information for each patient is usually maintained and updated daily by each physician. A verbal signout should also be performed, highlighting the most relevant information. It is often helpful to sign out while walking around the unit to briefly check on each patient. The signout should include:

  • Overall status: i.e., unstable, deteriorating, stable, or up for transfer
  • Reason for admission
  • Active issues (e.g., complications) and to-do list
  • Current neurological and mental status
  • Lines, tubes, and catheters
  • Anticipated and potential complications along with contingency plans
  • Code status and advance directives
  • Contact information for the patient's family

Transfer/discharge checklist

Patients are usually transferred to the general medical floor before being discharged, but some patients may be discharged directly from the ICU or cardiac intensive care unit.

  • Begin planning for transfer or discharge.
  • Begin ventilator weaning when the patient meets the criteria.
  • Deescalate medications (e.g., pressors, sedatives) and IV fluids as appropriate.
  • Convert medications from IV to PO form.
  • Advance the patient's diet.
  • Perform medication reconciliation.
  • Write a transfer note (this should be similar to a discharge summary).
  • Provide a verbal signout to the accepting service.
  • Update the patient's family as appropriate.

Related One-Minute Telegram

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External Resources

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  20. "Contributor Disclosures - Care of the critically ill patient. All of the relevant financial relationships listed for the following individuals have been mitigated: Alexandra Willis (copyeditor, was previously employed by OPEN Health Communications). None of the other individuals in control of the content for this article reported relevant financial relationships with ineligible companies. For details, please review our full conflict of interest (COI) policy:"