321 Approach to the Patient with Critical Illness Flashcards
It is the presence of multisystem end-organ hypoperfusion
Shock
What are the clinical indicators of shock?
Reduced mean arterial pressure (MAP) Tachycardia Tachypnea Cool skin and extremities Acute altered mental status Oliguria
Clinical evidence of diminished cardiac output
Narrow pulse pressure
Cool extremities with delayed capillary refill
Clinical evidence of increased cardiac output
Widened pulse pressure (particularly with a reduced diastolic pressure)
Warm extremities with bounding pulses
Rapid capillary refill
It is a better predictor of fluid responsiveness
Change in right atrial pressure as a function of spontaneous respiration
It is the most common cause of high-cardiac-output hypotension
Sepsis
Other causes of high cardiac hypotension
Liver failure, Severe pancreatitis Burns and other trauma that elicit the systemic inflammatory response syndrome (SIRS) Anaphylaxis Thyrotoxicosis Peripheral arteriovenous shunts
Reasons for the institution of endotracheal intubation and mechanical ventilation
Acute hypoxemic respiratory failure
Ventilatory failure
It often occurs as a consequence of an increased load on the respiratory system in the form of acute metabolic (often lactic) acidosis or decreased lung compliance due to pulmonary edema
Ventilatory Failure
This type of respiratory failure occurs with alveolar flooding and sub- sequent intrapulmonary shunt physiology
TYPE I: ACUTE HYPOXEMIC RESPIRATORY FAILURE
This type of respiratory failure is seen in sepsis, gastric aspiration, pneumonia, near drowning, multiple blood transfusions, and pancreatitis
TYPE I: ACUTE HYPOXEMIC RESPIRATORY FAILURE
This syndrome is defined by acute onset (≤1 week) of bilateral opacities on chest imaging that are not fully explained by cardiac failure or fluid overload and of shunt physiology requiring positive end-expiratory pressure (PEEP)
ARDS
This type of respiratory failure is a consequence of alveolar hypoventilation and results from the inability to eliminate carbon dioxide effectively
TYPE II RESPIRATORY FAILURE
The mechanisms involved in this type of respiratory failure are categorized by impaired central nervous system (CNS) drive to breathe, impaired strength with failure of neuromuscular function in the respiratory system, and increased load(s) on the respiratory system
TYPE II RESPIRATORY FAILURE
Examples of conditions in this type of respiratory failure are drug overdose, brainstem injury, sleep disordered breathing, and severe hypothyroidism, myasthenia gravis, Guillain-Barré syndrome, amyotrophic lateral sclerosis, myopathy, electrolyte derangements, and fatigue
TYPE II RESPIRATORY FAILURE
What is the mainstays of therapy for type II respiratory failure?
Reverse the underlying cause(s) of ventilatory failure
Subclassification of overall load on the respiratory system
Resistive Loads (bronchospasm)
Loads due to reduced lung compliance (e.g., alveolar edema, atelectasis, intrinsic positive end-expiratory pressure [auto-PEEP]
Loads due to reduced chest wall compliance (e.g., pneumothorax, pleural effusion, abdominal disten- tion)
Loads due to increased minute ventilation requirements (e.g., pulmonary embolus with increased dead-space fraction, sepsis)
This form of respiratory failure results from lung atelectasis
TYPE III RESPIRATORY FAILURE
This is also called preoperative respiratory failure
TYPE III RESPIRATORY FAILURE
This form of respiratory failure results from hypoperfusion of respiratory muscles in patients in shock
TYPE IV RESPIRATORY FAILURE
Screening criteria for spontaneous breathing trial
oxygenation is stable (i.e., PaO2/FIO2 [partial pressure of oxygen/fraction of inspired oxygen] >200 and PEEP ≤5 cmH2O)
Cough and airway reflexes are intact
No vasopressor agents or sedatives are being administered
Criteria for failure of spontaneous breathing trial
(1) respiratory rate >35/min for >5 min
(2) O2 saturation <90%
(3) heart rate >140/min or a 20% increase or decrease from baseline
(4) systolic blood pressure <90 mmHg or >180 mmHg
(5) increased anxiety or diaphoresis.
What is the mainstay of therapy for pain control in mechanically ventilated patients?
Opiates
Indications for sedation
Anxiolysis
Treatment of subjective dyspnea
Psychosis
Facilitation of nursing care
Reduction of autonomic hyperactivity, which may precipitate myocardial ischemia
Reduction of total O2 consumption (VO2)
It is defined by the simultaneous presence of physiologic dysfunction and/or failure of two or more organs
MULTIORGAN SYSTEM FAILURE
It is the gold standard for evaluation of respiratory gas exchange
ABG
Two variables that determine the peak airway pressure
Airway resistance
Respiratory system compliance
The difference between the peak (airway resistance + respiratory system compliance) and plateau (respiratory system compliance only) airway pressures provides a quantitative assessment of?
Airway resistance
It is defined by the change in pressure of the respiratory system per unit change in volume
Lung compliance
Normal respiratory system compliance
~100 mL/cmH2O
Processes that reduce chest wall compliance
Pleural effusions, pneumothorax, and increased abdominal girth
Conditions that reduce lung compliance
Pneumonia, pulmonary edema, interstitial lung disease, or auto-PEEP
It is determined by the hemoglobin concentration, the arterial hemoglobin saturation, and dissolved O2 not bound to hemoglobin
Content of O2 in the arterial blood (CaO2)
Oxygen delivery (QO2) in normal adult is equal to
1058 mL O2 per min
Conditions that reduced mixed venous O2 saturation
Inadequate cardiac output
Reduced hemoglobin concentration
Reduced arterial O2 saturation
Conditions that may abnormally increased VO2 in peripheral tissues
Fever, agitation, shivering, and thyrotoxicosis
It is defined as the presence of SIRS in the setting of known or suspected infection
Sepsis
It is the leading cause of death in noncoronary ICUs in the United States
Sepsis
All ICU patients are at high risk for this complication because of their predilection for immobility
DVT
DVT Prophylaxis
Subcutaneous low-dose heparin injections and sequential compression devices for the lower extremities, Enoxaparin, Fondaparinux
Stress ulcer prophylaxis
Histamine-2 antagonists or proton pump inhibitors
These are important issues that may be associated with respiratory failure, impaired wound healing, and dysfunctional immune response in critically ill patients
NUTRITION AND GLYCEMIC CONTROL
This state is defined by (1) an acute onset of changes or fluctuations in mental status, (2) inattention, (3) disorganized thinking, and (4) an altered level of consciousness (i.e., a state other than alertness)
Delirium
True or False: Very early physical and occupational therapy in mechanically ventilated patients has been demonstrated to reduce delirium
True
Treatment for vasospasm
Nimodipine, aggressive IV fluid administration, and therapy aimed at increasing blood pressure
It is the most effective benzo- diazepine for treating status epilepticus and is the treatment of choice for controlling seizures acutely
Lorazepam
