心臟疾病患者的護理

心臟疾病患者的護理

邱愛富

心臟血管系統的解剖 生理功能

邱愛富

一、心臟的構造與功能 :

• heart size: 拳頭， 250-350 gm

• heart location: 2/3 胸骨中線左側；

• Base:2^nd 肋骨； Apex:5th 肋間 & L’t 鎖骨 中線

• heart function:

– deliver O₂ and other essential substitute to tissu e of body

– remove CO₂ & 代謝產物

心臟壁層 :

• 心包膜 (pericardium)

– 1) 外層 ( 壁心包膜 ) ：纖維性—防止 heart 過度擴張

、有保護、固定

– 2) 內層 ( 臟心包膜 ) ：漿膜性—

– 兩層間為心包膜腔，含 15-50 cc 心包膜液，可防止收 縮時的磨擦

• 心外膜 (epicardium);

• 心肌 (myocardium)-- 不隨意肌，具橫紋及分枝的 纖維，有收縮作用

• 心內膜 (endocardium)

Coronary vasculature

• Right coronary artery (RCA ）、

• Left main--Left anterior descending artery (LAD) 、 Left circumflex (LCX)

• Ascending aorta (75% at diastolic)

 RCA (supply RA, RV, post LV, 90% AV node)

 Left main LAD (supply Ant. LV, apex) 、 LCX (supply lateral LV, LA)

The Cardiac Cycle

• Blood Circulation Circuits

– Pulmonary Circuit – lungs

– Systemic Circuit - whole body

• Cardiac Cycle

– Systole – contraction – Diastole – relaxation

– Atria relax when Ventricles contract and vice versa

Steps in a contraction

• When atria fill pressure opens AV valves

• Atria contraction fills ventricles completely

• Ventricles begin to contract and AV valves snap shut (LUB)

• Increased contraction (inc. pressure) forces semilunar valves open

• Blood flows into vessels leading away. Pressure increa ses and forces SL valves shut (DUB)

• Process begins again

Cardiac Output

• 心輸出量 (CO) = 心搏出量 (SV) x 心跳速率 (HR)

• 心搏出量 (Stroke volume) ：每一次心室收縮時所 排出的血量，同時受到前負荷，後負荷及心臟收縮 力的影響

• 心輸出量的決定因素

– 前負荷 (preload): 心室舒張末期 , 心肌所承受的張力 – 後負荷 (Afterload): 心室收縮時所遭遇的阻力

– 心臟收縮力 (Contractility)

– 心跳速率與節律 (heart rate & rhythm)

前負荷 (Preload)

• Frank-Starling 定律 : 舒張容積 (= 前負荷 )  心室收 縮強度  輸出容積

• (myocardium fiber length↑ preload ↑ LVEDV↑S V↑)

• 臨床上：以進入心室的血量多寡為代表（一般用 CVP 及 PAW P 估計）

Contractility 收縮力

• Vpk for the left ventricle is around 1.1 – 1.5 m/s in healthy patients.

• In patients with cardiac failure or low contr actility/inotropy this figure might well be on ly 0.6 or 0.7 m/s or even less.

• For the right ventricle the figure would be 0 .7 to 1.2 in healthy patients.

後負荷 (Afterload)

• Ohm’s law:

R =  P/Q

– SVR = (MABP – CVP)/CO (systemic vascul ar resistance)

– PVR = (MPAP – LAP)/CO (pulmonary vas cular resistance)

• 臨床評估 : SVR and PVR

A high BP meansthat the ventricle is pu

shing uphill High viscosity and vasoconstriction mean

Cardiac Output

• The amount of blood ejected by the left ventricl e in one minute

• CO = HR X SV

• Heart rate is 75 beats per min

• Stroke volume is 70 ml per beat

• Blood volume?? do calculation

• CO=SVxHR = 60-130 cc/beat X 75 beat/min = 4- 8 L/min

Cardiac function index

• Ejection Fraction 心射出分率

– Is % of blood ejected with every beat

– =SV/LVEDV=2/3=60-75% (Normal>50%) – Reflect LV performance

• Cardiac index(CI) 心臟指數

• Cardiac reserve 心臟儲備量

Cardiac index(CI) 心臟指數

• Is CO corrected for differences in body size

• =CO/body surface area= 2.5-4 L/min/m²

www.learnhemodynamics.com/hemo/contract.htm

Cardiac reserve 心臟儲備量

• Cardiac reserve= ability to respond to the de mand for increased CO (eg. Exercise,stress)

• Normal: 300-400%

Conduction System

• Sinoatrial node (SA node) - RA, "fastest" autorhythmic ti ssue (pacemaker, 60-100 bpm)

• Atrioventricular node (AV node) - last part of atria to de polarize signal hesitates then proceeds to ventricles (40-6 0 bpm)

• AV bundle (bundle of His) - connects atria to ventricles

• Rt and Lt bundle branches - send signal to apex of heart

• Purkinje fibers - action potential sent throughout ventricl e tissue (20-40 bpm)

心臟電氣生理特性

• 自律性

的能力，規則自動的激發衝動 (Impulses)

的能力，主要由 SA node 擔任 Pacemaker 激搏點

• 興奮性

去極化的能力 ( 被衝動激發產生興奮 )

• 傳導性

• 不反應期 (Refractoriness)-- 心肌仍然處 於前一刺激之收縮，無法對於新刺激反 應的時期

Neurologic Control of the Heart

• Autonomic nervous system ( 自主神經的控 制 )

– Sympathic  NE β1 ↑HR, contractil ity↑CO,BP

– Parasympathic ACH ↓HR, contractili ty

壓力接受器 (Baroreceptor) 與化 學接受 (Chemoreceptor)

• 壓力接受器 (Baroreceptor ：位於頸動脈竇、主 動脈竇、心房

– BP↑baroreceptortrasfer massage to vasom otor center at medula stimulate parasymp.

inhibit symp. ↓HR, contractility

• 化學接受器 (Chemoreceptor) ：位於頸動脈體、

主動脈體附近

– PO2, PH, PCO2↓ stimulate chemreceptor va somotor center↑cardiac activity ↑PO2

 心臟血管疾病的評估及診 斷檢查 

• Nursing assessment: history, Golden

• Physical examination

• Diagnostic tests

– Laboratory

– Hemodynamic monitoring – Non-invasive tests

• ECG, Treadmill, Echo, Nuclear cardiology, CT, MRI

– Invasive tests

• Cardiac catheterization, Coronary angiography, electrophysiol ogic study (EPS), endomyocardial biopsy(EMB), TEE, IVUS

Nursing assessment

• Main complaint:

– chest pain, dyspnea, fatigue, edema, palpitation, syncope

• History of present illness:

– onset, signs & symptoms

• Past medical history:

– previous illness, injuries, surgery, medication

• Risk factors: family history, smoking, activity, diet, pe rsonality

• Golden’s 11 functional health patterns

Chest Pain Assessment

Assessment Angina Pericarditis

Provocation/

Palliation

Exercise/rest Deep breath, 平躺 / 前傾、坐起

Quality/

Quantity

壓迫感、沉重、消 化不良感

尖銳如刀割

Region/Radiation 胸骨、頸、左手臂

、肩

↑

Severity 中度 中至重度

Time/onset, <10 min Several hrs to days

Dyspnea

• SOB (short of breath) 呼吸短促

• DOE (Dyspnea on exercise/exertion) 運動時呼吸 困難 , 最常見於 walk, crimb stair

• Orthopnea 端坐呼吸 , 無法平躺，半坐臥緩解

• PND (paroxysmal nocturnal dyspnea) 夜間陣發性 呼吸困難 ,

Physical examination- Inspection

• skin: central cyanosis (lip, mouth, conjundi val)poor arterial circulation

• peripheral cyanosis(lip, ear, nail)peripher al vasoconstriction

• Eyes: arcus senitis 老人弓 , Xanthelasma 黃斑瘤  atherosclerosis

Physical examination- Inspection

• Fingers clubbing 杵狀指 PO2↓or lun g cancer

• Capillary refill (circulation): press nail to br anches,color return<2 sec

Physical examination- Inspection

• Skin tugor (elastrictry): 捏起 skin, return ti me>30 secdehydration, BW↓

• Edema: press 5 sec, remove(+<1/4”, ++ 1/4

”-1/2”, +++1/2”-1”)

Physical exam-Vital sign

• BP:

– bilateral BP: L’t & R’t SBP difference>15 mmHg↓aorta blood flow in lower arm – Pulse pressure:SBP-DBP=30~50,

– Orthostatic BP: lying-standing>20dehydration, poor HTN, aorta disease

Physical exam-Vital sign

• pulse: rate, rhythm, amplitude, bilateral

– pulsus paradoxus( 奇脈 ): pulse change with 呼吸 , 吸 氣 pulse weaken, BP↓

– pulsus alternanus( 交替脈 ):pulse change with HR, – pulsation:0=none, +=weak, ++=normal, +++=strong

Physical examination

• Carotid artery: thrill, bruit(vessel murmur): arteria l narrowing

• Jugular vein pressure (JVP)<2 cm

• Hepatojugular reflux

Physical examination

• Palpation & Auscultation of precordium

– Areas: aortic, pulmonary, tricuspid, mitral, apex , PMI

– S1, S2, Abnormal heart sounds: murmur, click, friction rub

Diagnostic studies

• Laboratory ：

– CBC, e-, Cholesterol, HDL, LDL, TG, cardiac enzymes ( CPK-MB, LDH, troponinT & I, myoglobin)

PT(prothrombin time), (International normalized ratio;

INR) 、 PTT, BUN, Cre, glucose

• Hemodynamic monitoring

– CVP=4~12 cmH2O; reflect RA pressure – Swan-Ganz: PAWP

EKG

12 lead EKG

• 雙極肢體導程 ( 縱切面 ): I, II, III

• 單極肢體導程 ( 縱切面 ):aVR, aVL, aVF

• 胸導程 ( 橫切面 ): V1, V2, V3, V4, V5, V6

Normal EKG

Holter Monitoring

• can record heart rate and rhythm when

patients feel chest pain or symptoms of an arrhythmia over a 24-hour period

• Ambulatory ECG; Dynamic ECG

• Developed in 1960s

Exercise Stress Tests (Treadmill

; 運動心電圖 )

• Dx :CAD, functional capacity Target HR=85%*max HR

Positive: ST depression>1mm

• Contraindications:

– Unstable angina with recent chest pain – Critical aortic stenosis

– Severe hypertrophic obstructive cardiomyopathy – Untreated life-threatening cardiac arrhythmias – Uncompensated congestive heart failure

– Advanced AV block

– Acute myocarditis or pericarditis – Uncontrolled hypertension

Echocardiography 超音波

• uses sound waves to produce an image of the heart an d to see how it is functioning.

• Transducer high frequency, short wave return

示波鏡、描繪圖影像

• show the size, shape, and movement of the heart mus cle, valves disease,blood flow, arteries.

• Types

– Motion-mode( 收縮、活動 ),

– 2 Dimensional-echo( 縱、橫向結構 ), – Doppler( 血流方向、流速 )

Transesophageal Echocardiogr aphy (TEE)

• The test is like standard echocardiography except that the pictures of the heart come from inside the esophagus rather than through the chest wall.

• NPO 6-8 hoursspraying throat with an

anesthetica tube (probe) put down the throat

• Gag reflex return,then eating

Intravascular Ultrasound (IVUS)

• is a combination of echocardiography and cardiac catheterization.

• uses sound waves, which are sent through a cathet er to artery and heart, to produce an image of the c oronary arteries and to see their condition.

• is rarely done alone or as a strictly diagnostic proc edure. It is usually done with a transcatheter interv ention like angioplasty.

Chest X ray

• Most commonly performed imaging test for CV system

• For evaluation of cardiac chamber size and great vessels

Chest X ray with enlarged heart size

Nuclear cardiology ( 心臟核子醫 學檢查 )

• Ejection fraction + wall motion

– Evaluation of cardiac performance and regional wall m otion

• Left ventricular diastolic phase index (MUGA)

– Useful for evaluation of diastolic function – Patients with atrial fibrillation

Nuclear cardiology

•

– Myocardial perfusion imaging – TET Tl-201, Persantin Tl-201

•

– Myocardial blood flow and myocardial viability

Nuclear Cardiology

• Tc99 鎝同位素 (hot spot) ：與壞死心肌之 Ca

結合 聚集於受損或梗塞之心肌部位

凸顯梗塞之心肌部位

 MI 4 hours 可發現， 24-72hrs 最靈敏

• Thallium 201 myocardial imaging 鉈 (cold sp ot): 測心肌灌注情形

– 聚集於心肌供血處，灌注好分佈均勻，缺 血處無法進入空白冷點 (cold spot)

Computed tomography (CT scan)

• Cardiac dimensions, calcifications and function – Ischemic heart disease, LV aneurysm, etc.

•

– Pericardial effusion, constrictive pericarditis, pe ricardial cyst

•

•

•

– Aortic dissection, aortic aneurysm

•

Magnetic Resonance Imaging (MRI)

• Provide a 2-D view of the heart, including the chambers and valves, without having to inject a dye or insert a catheter.

• Interfere with pacemaker function

• Can’t use with prosthetic metallic devices (valves, prosthetic joints, pacemaker etc.

Invasive tests

•

– Coronary angiography (CAG)

• Electrophyiologic study (EPS)

• Endomyocardial biopsy (EMB)

心導管術的功能有哪些？

• 在檢查方面可以達到顯影評估心臟功能、

血流的情況或是血管阻塞的情形、記錄心 臟氧氣變化、測量心臟電位、測量心臟血 管各部位的壓力等。

• 在治療方面可以利用氣球擴張術或置入支 架撐開阻塞的血管段、將心律不整的原因 給予電燒灼，以及放置心律調整器等。

心導管檢查前需注意之事項

• 由醫師解釋心導管檢查的利弊，並簽寫同 意書。

• 禁食 4-6 小時。

• 檢查部位（穿刺部位）毛髮剔除。

• 檢查四肢末梢動脈循環及做上記號。

• 須換上手術衣，並取下假牙、義眼、眼鏡

、及所有飾物等。

• 檢查前先排空膀胱。

施行心導管之禁忌症

• 絕對禁忌

– 病患拒絕

– 設備或儀器不足

• 相對禁忌

– 控制不良之心臟衰竭 , 高血壓 , 心律不整 – 一個月以內之腦中風

– 發燒 / 感染 – 電解質不平衡 – 急性消化道出血 – 懷孕

– 易出血之體質或情形 – 無法合作之病人

– 腎衰竭

Cardiac catheterization

• post-cath ：

– vital sign: q15min *4 → q30 min *2 (or 4) → q1h – 股動脈 :bed rest 6-8 hours, compress 4-6 hrs

– 橈動脈 : bed rest 1-2 hours, compress 2 hrs – check wound: bleeding ？ infection ？

– check P+P (pulsation&perfusion) ？

• complications ： bleeding, hemotoma, dye allergy , arrhythmia, thrombus

EPS (Electrophysiologic study)

• understand arrhythmia mechanism (eg. Add itional pathway)

• effects of drugs and ablation

• decide the need of pacemaker

Endomyocardial Biopsy(EMB)

Grade Finding Rejection Severity

0 No infiltrates None

1A Focal (perivascular of interstisial infiltrates without necr

osis Mild

1B Diffuse but not sparse infiltrate without necrosis Mild 2 One focus only with aggressive infiltrate and/or myocyte

damage Focal Moderate

3A Multifoca addressive infiltrates and/or myocyte damage Moderate

3B Diffuse inflammatory infiltrates with necrosis Borderline severe 4D Diffuse aggressive polymorphous infiltrate with edema, Severe

• International Society for Heart & Lung Transplantation End omyocardial Biopsy Grading Scheme

Review

• Anatomy and physiology of the heart

• Physical examination of cardiovascular syst em

• Nursing assessment

• Non-invasive tests: Lab., chest X-ray, EKG, echo, Nuclear cardiology, CT, MRI

• Invasive tests: Cath, EPS, EMB, TEE, IVU S