CCRN Exam Notes 2022/23

Which of the following does not predispose the patient to digitalis toxicity? Hyponatremia. Remember that potassium, calcium, and magnesium affect cardiac contractility, Which single lead is the most valuable for the diagnosis of ventricular tachycardia? V1 Cardio Sites of MIs Inferior MI - Right Coronary (RC), associated with papillarymuscle ruputure Indicative Changes: II, III, aVFReciprocal Changes: I, AVL Anterior MI - Left Anterior Descending (LAD), associated with ventricular septal ruputure (holosystic murmur) Indicative Changes: V2, V3, V4 Reciprocal Changes: II, III, AVF Septal Wall - Left Anterior Descending (LAD)Indicative Changes: V1 , sometimes V2 Reciprocal Changes: V5, V6 Lateral MI - Circumflex Artery Indicative Changes: I, AVL, V5, V6Reciprocal Changes: II, III, AVF Posterior Wall MI - Right coronary, if dominantIndicative Changes: V7, V8, V9 Reciprocal Changes: V1, V2, V3 **Remember posterior Wall MI has leads that are high numbers, post means after soassociate these two • murmur is loudest at the apex, and the clinical presentation is related to acute pulmonary edema.2 Cardiac Values3 Swanz gaz – measures pressure , cardiac output , and oxygen PAOP 6-12mmHg (left atrial pressures = left ventricular end-diastolic pressure)(aka left ventricular preload) PAWP (pulmonary artery wedge pressure) 4-12mmHG (in the pulmonaryartery), inflate for 3-5 seconds and will have direct measurement of from back pressure. PAOP or PAWP 4 = hypovolemic patientPAOP or PAWP 4 = hypervolemic patient The PAd is normally 2 to 5 mm Hg higher than the PAOP. PAd may be more than 5 mm Hg higher than the PAOP in patients with pulmonary hypertension. If the PAOP is higher than the PAd, suspect that there is an occlusion in the catheter or that the catheter is not in the correctarea of the pulmonary vasculature. The RAP is normally lower than the PAOP. RAP/CVP 2-6mmHg or 1-8( right atrium pressure) Optimal in Critical Care Can be up to 10mmHg PAP (pulmonary artery pressure) – could be systolic and diastolicPAP systolic – 15-26 mmhG PAD diastolic 5-15 mmHG Cardiac tamponade would cause an increase in RAP, PAP, and PAOP. SV02 –mixed venous saturation of l 60-80% It is basically the percentage of oxygen remaining in the venous blood returning to the right side of the heart. This is the oxygen left over in theblood after supplying all the parts of the body except the head. Systolic – squeeze Diastolic – relaxation and filing CO 4-8 L/min CI 2.5-4.3 L/min/m² Stroke Volume 60-1004 mL/beat Stroke Volume