Critical Care and Emergency Flashcards

A patient with severe sepsis has a serum lactate of 6.2 mmol/L. According to the Surviving Sepsis Campaign (SSC) guidelines, what is the target for lactate clearance within the first 6 hours?

Answer: Decrease by at least 20% within 6 hours

The Surviving Sepsis Campaign recommends targeting at least a 20% reduction in serum lactate within the first 6 hours as a marker of adequate resuscitation. Lactate clearance serves as a surrogate for improved tissue perfusion and oxygen delivery. Serial lactate measurements guide the adequacy of fluid resuscitation, vasopressor therapy, and source control.

In the primary survey of a trauma patient (ATLS), after addressing airway with cervical spine control, what is the next priority?

Answer: Breathing and ventilation

The ATLS primary survey follows the ABCDE sequence: Airway (with C-spine protection), Breathing (and ventilation), Circulation (with haemorrhage control), Disability (neurological status), and Exposure (with environmental control). After securing the airway, assessment of breathing is the next priority — look for tension pneumothorax, open pneumothorax, flail chest, and massive haemothorax, which are immediately life-threatening.

A patient in the ICU develops acute respiratory distress syndrome (ARDS). According to the Berlin definition, what PaO2/FiO2 ratio defines moderate ARDS?

Answer: 100-200 mmHg

The Berlin definition classifies ARDS severity by PaO2/FiO2 ratio on PEEP >= 5 cmH2O: Mild = 200-300 mmHg, Moderate = 100-200 mmHg, Severe = <100 mmHg. Moderate ARDS has a mortality of approximately 32%. Management includes lung-protective ventilation (tidal volume 6 ml/kg ideal body weight), permissive hypercapnia, and prone positioning for severe cases.

A 70 kg patient with 40% total body surface area full-thickness burns presents 1 hour post-injury. Using the Parkland formula, what volume of Hartmann's solution should be administered in the first 8 hours from the time of burn?

Answer: 5600 ml

Parkland formula: 4 ml x body weight (kg) x %TBSA burned = 4 x 70 x 40 = 11,200 ml in the first 24 hours. Half of this (5,600 ml) is given in the first 8 hours from the time of burn injury, and the remaining half over the next 16 hours. The fluid is titrated to maintain urine output of 0.5-1 ml/kg/hour in adults.

Which scoring system is used in UK emergency departments to assess the severity of community-acquired pneumonia and guide admission decisions?

Answer: CURB-65

CURB-65 scores one point each for: Confusion (AMT 7 mmol/L, Respiratory rate >= 30, Blood pressure (systolic = 65 years. Score 0-1: home treatment; 2: consider hospital admission; 3-5: consider ICU. It is recommended by NICE and the British Thoracic Society for community-acquired pneumonia assessment.

A post-operative patient develops a pulmonary embolism with haemodynamic instability (systolic BP 70 mmHg). What is the definitive pharmacological treatment?

Answer: Systemic thrombolysis with alteplase

Massive (high-risk) pulmonary embolism with haemodynamic compromise requires systemic thrombolysis. Alteplase (50-100 mg IV over 2 hours) is the standard agent. NICE and ESC guidelines recommend thrombolysis for PE with sustained hypotension (systolic <90 mmHg). While heparin is given adjunctively, it does not dissolve existing clot. Surgical embolectomy or catheter-directed therapy are alternatives if thrombolysis is contraindicated.