The emergency department nurse evaluates that fluid resuscitation for a 70 kg patient in shock is effective by finding which one of the following?

The QTc (corrected QT) interval is a measure of the time it takes for the ventricles to depolarize and repolarize during a cardiac cycle. It is corrected for heart rate (HR) to account for variations in the cardiac cycle length.
The normal range for the QTc interval varies depending on the calculation method used but generally falls within 0.36 to 0.44 seconds. In the given options, the range of 0.33 to 0.47 seconds for the QTc interval is wider than the normal range, suggesting a prolonged QTc interval, which can be indicative of a potential risk for arrhythmias, including ventricular tachycardia and torsades de pointes.
B. QT interval that varies with HR in (option B) is normal because The QT interval alone can vary with heart rate, and this is considered a normal physiological adaptation.
C. QRS interval <0.12 seconds in (option C) is normal because The QRS interval represents the time it takes for ventricular depolarization and is normally less than 0.12 seconds.
D. PR interval 0.12 to 0.24 seconds in (option D) is normal because The PR interval represents the time it takes for atrial depolarization and conduction through the AV node. The normal range is typically 0.12 to 0.20 seconds.

Norepinephrine is a potent vasoconstrictor and inotropic agent commonly used to increase blood pressure in cases of hypotension or shock. However, if the infusion rate is too high, it can lead to excessive vasoconstriction and potentially compromise organ perfusion.
A heart rate of 58 beats/min suggests bradycardia, which can be an indication of excessive vasoconstriction caused by a high dose or rate of norepinephrine infusion. Excessive vasoconstriction can reduce cardiac output and worsen tissue perfusion.
A. Mean arterial pressure is 55 mm Hg in (option A) is incorrect because A mean arterial pressure of 55 mm Hg may be within an acceptable range for a patient receiving norepinephrine infusion, depending on the patient's baseline blood pressure and clinical condition.
B. Systemic vascular resistance (SVR) is elevated in (option B) is incorrect because An elevated SVR indicates increased peripheral vascular resistance and can be a desired effect of norepinephrine infusion to improve blood pressure and perfusion.
C. Pulmonary artery wedge pressure (PAWP) is low in (option C) which is incorrect because A low PAWP may indicate decreased left ventricular preload, which can be a desired effect of norepinephrine infusion to reduce fluid overload in certain clinical conditions.
It is important for the nurse to carefully monitor the patient's hemodynamic parameters, including blood pressure, heart rate, and organ perfusion when titrating norepinephrine infusion to ensure optimal dosing and minimize potential adverse effects. If concerns arise regarding the infusion rate, the healthcare provider should be promptly notified for further evaluation and adjustment of the treatment plan.