Critical Care Nursing Flashcards

A 58-year-old male in the ICU is on mechanical ventilation with the following ABG results: pH 7.22, PaCO₂ 38 mmHg, HCO₃⁻ 15 mEq/L, PaO₂ 88 mmHg, SaO₂ 94%. His anion gap is 24 mEq/L (Na⁺ 138, Cl⁻ 99, HCO₃⁻ 15). Which condition is MOST consistent with this presentation?

Answer: Diabetic ketoacidosis with compensatory hyperventilation masked by ventilator settings

The ABG shows metabolic acidosis (low pH, low HCO₃⁻) with a normal PaCO₂, indicating the ventilator is not allowing appropriate compensatory hyperventilation (expected PaCO₂ via Winter's formula = 1.5×15 + 8 ± 2 = 29–31 mmHg). The elevated anion gap of 24 mEq/L points to an anion-gap metabolic acidosis such as DKA. In Saudi ICU practice, DKA is among the leading causes of high anion gap metabolic acidosis; the ventilator settings must be adjusted to permit adequate CO₂ clearance to avoid worsening acidemia.

A critically ill patient in a SCFHS-accredited tertiary ICU develops sudden hemodynamic deterioration 48 hours post-cardiac surgery. Bedside echocardiography reveals a large pericardial effusion with right ventricular diastolic collapse. His CVP is 22 mmHg, BP 78/50 mmHg, and heart sounds are muffled. The nurse anticipates which of the following as the MOST immediate nursing priority BEFORE the physician performs pericardiocentesis?

Answer: Administer a 500 mL IV fluid bolus of 0.9% NaCl to optimize preload

Cardiac tamponade causes obstructive shock; the heart cannot fill adequately due to external compression. The immediate nursing priority is IV fluid resuscitation to maximize preload and maintain cardiac output until the definitive procedure (pericardiocentesis) is performed. While vasopressors can be considered adjuncts, fluids are the first-line hemodynamic support. Cardioversion is not indicated as the rhythm disturbance is secondary to tamponade. Reducing PEEP may slightly help but is not the priority intervention in this context per SCFHS and SCCM critical care guidelines.

In a Saudi MOH ICU, a nurse is caring for a patient receiving continuous renal replacement therapy (CRRT) via CVVHDF mode. The blood flow rate is 200 mL/min, effluent rate is 35 mL/kg/hr, and the patient's serum phosphate is 0.45 mmol/L (normal: 0.87–1.45 mmol/L). The patient is hemodynamically stable. What is the MOST appropriate nursing intervention?

Answer: Notify the physician and anticipate phosphate supplementation to the replacement fluid or IV

Hypophosphatemia is a well-recognized complication of CRRT, particularly at high effluent rates, as phosphate is freely filtered. A serum phosphate of 0.45 mmol/L represents severe hypophosphatemia (normal lower limit ~0.87 mmol/L in Saudi/SI units), which can cause respiratory muscle weakness, cardiac dysfunction, and impaired weaning from ventilation. The correct action is to notify the physician and anticipate phosphate replacement — either added to the replacement/dialysate fluid or given IV. Increasing the effluent rate would worsen phosphate loss. Oral phosphate binders are used to reduce phosphate in hyperphosphatemia, not treat hypophosphatemia. Discontinuing CRRT is not clinically justified.

A 42-year-old female with septic shock secondary to urosepsis is in a SCFHS ICU on norepinephrine 0.25 mcg/kg/min and vasopressin 0.03 units/min. Despite adequate fluid resuscitation (30 mL/kg crystalloid given), her MAP remains 58 mmHg. Her cortisol stimulation test (ACTH stimulation) shows a delta cortisol rise of 150 nmol/L. According to current Surviving Sepsis Campaign guidelines adopted in Saudi Arabia, which intervention is MOST appropriate?

Answer: Add hydrocortisone 200 mg/day IV as a continuous infusion

Per the Surviving Sepsis Campaign 2021 guidelines (adopted by SCFHS and Saudi MOH ICU protocols), hydrocortisone 200 mg/day IV (as continuous infusion or 50 mg q6h) is recommended for septic shock patients who remain hemodynamically unstable despite adequate fluids and vasopressor therapy — regardless of ACTH stimulation test results (the test is no longer used to guide corticosteroid use in septic shock). Adding fludrocortisone is not routinely recommended per current SSC guidelines. Terlipressin is not a standard substitution for vasopressin in septic shock and carries risk of digital ischemia. Increasing norepinephrine first without corticosteroids when already on two vasopressors is not the guideline-recommended sequence.

A mechanically ventilated patient in a Saudi ICU has developed ventilator-associated pneumonia (VAP). Culture results show Klebsiella pneumoniae producing extended-spectrum beta-lactamase (ESBL). The patient has a creatinine clearance of 28 mL/min. Which antibiotic regimen is MOST appropriate per Saudi MOH Antimicrobial Stewardship Program guidelines for ESBL-producing organisms in the ICU setting?

Answer: Meropenem 1 g IV q12h (renally adjusted) as monotherapy

ESBL-producing Enterobacteriaceae, including Klebsiella pneumoniae, are resistant to all penicillins and cephalosporins including piperacillin-tazobactam (which shows in vitro susceptibility but clinical failure — the 'inoculum effect'). The Saudi MOH Antimicrobial Stewardship guidelines and international VAP guidelines (IDSA/ATS) recommend a carbapenem as the definitive treatment. Meropenem 1 g q12h is appropriate with renal dose adjustment for CrCl 28 mL/min. Ertapenem lacks Pseudomonas coverage (important in VAP) and combining it with colistin is not indicated without pan-resistant organisms. Ceftriaxone is ineffective against ESBL producers.

A nurse in a Level III ICU accredited by CBAHI (Central Board for Accreditation of Healthcare Institutions) in Saudi Arabia is performing a daily spontaneous awakening trial (SAT) followed by a spontaneous breathing trial (SBT) on a post-ARDS patient. During the SBT on a T-piece at 30 minutes, the patient develops: RR 32 breaths/min, SpO₂ 91%, accessory muscle use, and a RSBI (Rapid Shallow Breathing Index) of 115 breaths/min/L. What is the MOST appropriate next step?

Answer: Terminate the SBT immediately and return the patient to pre-SBT ventilator settings

The patient is demonstrating clear SBT failure criteria: RR >30 breaths/min, SpO₂ 105 breaths/min/L (a threshold associated with SBT failure and extubation failure). Per CBAHI-endorsed ICU liberation protocols (aligned with ABCDEF bundle and ACCP/ATS guidelines), the SBT must be terminated immediately upon meeting failure criteria to prevent fatigue and hemodynamic compromise. The patient should be returned to comfortable, pre-SBT ventilator settings. Continuing for 120 minutes despite failure signs risks respiratory muscle fatigue. Extubation is contraindicated. Switching to PSV restarts rather than terminates the failed SBT and does not address immediate distress.