A client is on mechanical ventilator settings that include the use of PEEP (positive end-expiratory pressure). Which finding indicates the client is developing a complication related to this therapy and requires immediate treatment?

A. HCO₃ 26 mmHg is incorrect because this bicarbonate level is within normal range (22–28 mEq/L) and does not indicate a complication of PEEP therapy. PEEP primarily affects cardiovascular and pulmonary dynamics rather than directly altering serum bicarbonate. B. BP 70/45 is correct because hypotension is a known and potentially serious complication of PEEP. Positive end-expiratory pressure increases intrathoracic pressure, which can reduce venous return (preload) to the heart. This decrease in preload lowers cardiac output, leading to hypotension. In severe cases, this can result in inadequate perfusion to vital organs, causing shock and organ failure. Immediate interventions may include lowering PEEP, administering intravenous fluids to increase intravascular volume, or starting vasopressors to support blood pressure. Continuous monitoring is essential. C. Central venous pressure (CVP) of 7 mmHg is incorrect because this value is within normal limits (typically 2–8 mmHg). CVP helps estimate right ventricular preload, and a normal CVP does not indicate hemodynamic compromise. In PEEP-related complications, CVP may actually increase due to elevated intrathoracic pressure, but a value of 7 mmHg is not concerning. D. Ventilator RR set at 14 and the client initiating spontaneous breaths for a total rate of 18 is incorrect because spontaneous breathing superimposed on ventilator settings is common and generally safe. A slight increase in total respiratory rate does not indicate a complication of PEEP and does not require immediate intervention.