Critical Care

Critical Care Indian Medical PG Question 1: IV fluid replacement (volume & rate) in a trauma patient is determined by:

• A. Chest condition
• B. BP
• C. CVP
• D. Urine output (Correct Answer)

Critical Care Explanation: ***Urine output*** - **Urine output** is a sensitive indicator of **renal perfusion** and overall **hemodynamic stability**, reflecting adequate tissue perfusion and fluid resuscitation in trauma patients. - Maintaining a urine output of **0.5-1.0 mL/kg/hour** is a common target during fluid resuscitation, demonstrating effective restoration of circulating volume. *Chest condition* - The **"chest condition"** (interpreted as respiratory status or thoracic trauma) primarily guides management of ventilatory support and thoracic interventions, not directly IV fluid rates. - While significant chest trauma can impact hemodynamics, it does not alone determine the specific **volume and rate** of IV fluid resuscitation. *BP* - **Blood pressure (BP)** can be a delayed and insensitive indicator of **hypovolemia** in trauma, as compensatory mechanisms can maintain BP until significant blood loss has occurred. - Relying solely on BP may lead to inadequate resuscitation or fluid overload, especially in patients with pre-existing hypertension. *CVP* - **Central Venous Pressure (CVP)** reflects **right atrial pressure** and can be influenced by multiple factors, including cardiac function, intrathoracic pressure, and venous tone, making it an unreliable sole indicator of fluid status in trauma. - CVP measurements can be misleading in situations like **cardiac tamponade** or **tension pneumothorax**, which are common in severe trauma.

Critical Care Indian Medical PG Question 2: The following are features of hypovolemic shock except:

• A. Acidosis
• B. Oliguria
• C. Low Blood Pressure
• D. Bradycardia (Correct Answer)

Critical Care Explanation: ***Bradycardia*** - Hypovolemic shock typically causes **tachycardia** (increased heart rate) as a compensatory mechanism to maintain cardiac output in the face of reduced blood volume [1]. - **Bradycardia** is generally not a feature of hypovolemic shock unless there are confounding factors or severe terminal stages. *Acidosis* - **Lactic acidosis** is a common feature of hypovolemic shock due to tissue hypoperfusion causing anaerobic metabolism [2]. - Reduced blood flow leads to inadequate oxygen delivery, forcing cells to produce lactic acid. *Oliguria* - **Oliguria** (decreased urine output) occurs in hypovolemic shock as the kidneys attempt to conserve fluid due to reduced renal perfusion. - The body prioritizes blood flow to vital organs, leading to decreased kidney function and urine production. *Low Blood Pressure* - **Hypotension** (low blood pressure) is a hallmark of shock, including hypovolemic shock, resulting from a significant reduction in circulating blood volume [1]. - The decrease in blood volume directly reduces venous return, stroke volume, and ultimately, systemic blood pressure.

Critical Care Indian Medical PG Question 3: Neurogenic shock is characterized by:

• A. Hypotension and bradycardia (Correct Answer)
• B. Hypotension and tachycardia
• C. Hypertension and tachycardia
• D. Hypertension and bradycardia

Critical Care Explanation: ***Hypotension and bradycardia*** - **Neurogenic shock** results from the loss of **sympathetic vascular tone**, leading to widespread vasodilation and subsequent **hypotension**. - The interruption of sympathetic innervation to the heart can also cause **bradycardia**, as parasympathetic tone becomes unopposed. *Hypotension and tachycardia* - This presentation is typical of other forms of shock, such as **hypovolemic** or **septic shock**, where the body attempts to compensate for low blood pressure with an increased heart rate. - In neurogenic shock, the sympathetic nervous system, which usually causes tachycardia, is dysfunctional. *Hypertension and tachycardia* - This combination is not characteristic of any form of shock; rather, it often indicates a **hyperadrenergic state** or certain types of **hypertensive crisis**. - Shock is fundamentally a state of inadequate tissue perfusion, which typically involves hypotension. *Hypertension and bradycardia* - This combination can be seen in conditions like **Cushing's reflex** (due to increased intracranial pressure) but is not a feature of neurogenic shock [1]. - Neurogenic shock is defined by a loss of sympathetic tone, which leads to vessel dilation and reduced blood pressure.

Critical Care Indian Medical PG Question 4: While performing triage in response to a disaster emergency, commonly an internationally accepted four-colour code system is used. Which one among the following four-colour categories represents the highest priority for emergency response ?

• A. Green
• B. Red (Correct Answer)
• C. Black
• D. Yellow

Critical Care Explanation: ***Red*** - The **red** category is assigned to patients with **immediate, life-threatening injuries** who have a high probability of survival with prompt medical intervention. - This color signifies the **highest priority** for medical treatment and transport to maximize their chances of survival. *Green* - The **green** category is for patients with **minor injuries** that are not life-threatening and can wait for medical attention. - These individuals are often referred to as walking wounded and can typically self-evacuate or wait for more critical patients to be treated. *Black* - The **black** category is reserved for patients who are either **deceased** or have injuries so severe that survival is unlikely, even with immediate medical care. - In a mass casualty situation, resources are generally not allocated to these individuals to prioritize those with a higher chance of survival. *Yellow* - The **yellow** category is for patients with **significant injuries** that are not immediately life-threatening but require definitive medical care within a few hours. - These patients are considered "delayed" and their treatment can be postponed until after red-category patients have been managed.

Critical Care Indian Medical PG Question 5: Which of the following is most associated with respiratory alkalosis?

• A. SIMV
• B. Non invasive ventilation
• C. Pressure controlled
• D. Assisted control mode ventilation (Correct Answer)

Critical Care Explanation: ***Assisted control mode ventilation*** - In **assisted control mode**, every patient effort above a set sensitivity triggers a fully supported breath at the set tidal volume or pressure, leading to the potential for **excessive ventilation** and respiratory alkalosis if the patient's respiratory drive is high. - This mode ensures a **minimum number of breaths** per minute, but also delivers full mechanical breaths for any additional patient-initiated breaths, which can result in **hyperventilation**. *SIMV* - **Synchronized intermittent mandatory ventilation (SIMV)** delivers a set number of mandatory breaths, but patient-initiated breaths between these mandatory breaths are either unsupported or supported at a lower level, making it less prone to causing excessive ventilation and alkalosis compared to AC. - SIMV allows for more patient participation in breathing and is often used to **wean patients off ventilation**, whereas AC prioritizes full ventilatory support. *Non invasive ventilation* - While **non-invasive ventilation (NIV)** can cause respiratory alkalosis if settings are too aggressive, it is generally used to avoid intubation and often allows for more patient control over their breathing pattern than AC, especially in modes like BiPAP where inspiratory and expiratory pressures are set. - The goal of NIV is to provide ventilatory support without an artificial airway, and it can be titrated to prevent both hypoventilation and hyperventilation more easily than the full support of AC. *Pressure controlled* - **Pressure-controlled ventilation** delivers breaths until a set inspiratory pressure is reached, with tidal volume varying based on lung compliance and resistance. While it can cause respiratory alkalosis if the set pressure or respiratory rate is too high, it is a *mode* of ventilation rather than a specific *type* of ventilatory support that inherently overventilates. - It focuses on limiting peak inspiratory pressures to protect the lungs, and can be used in either AC or SIMV modes, making its association with alkalosis dependent on specific settings and patient interaction.

Critical Care Flashcard 1 of 5

Question: Which scoring (SOFA/qSOFA) is particularly useful in the ICU setting?_____

Answer: SOFA

Critical Care Flashcard 2 of 5

Question: Vital capacity mechanical ventilation

Answer: Vital capacity mechanical ventilation

Critical Care Flashcard 3 of 5

Question: The _____ score is used to assess organ failure in acute pancreatitis.

Answer: SOFA

Critical Care Flashcard 4 of 5

Question: According to surviving sepsis criteria the mixed venous oxygen saturation should be _____ mmHg

Answer: >65%

Critical Care Flashcard 5 of 5

Question: _____natremia (hypovolemia) is seen only with seawater drowning

Answer: Hyper