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An 84 year-old man experienced an episode of
unexpected hypotension and consciousness
disturbance.
Brief History
The 84 year-old man, a
patient of hypertension with regular treatment for 10 years,
kept well before with a fit exercise tolerance. He felt dizzy
on the morning of the 26th of October, but he
still could ride a bike to see his friend. An
episode of fainting with consciousness change happened later.
He was sent to a local hospital where hypotension
(80/50 mmHg) was noticed. After
being managed with fluids and inotropes, he
was transferred to an ER in
a university hospital. At the ER, hypotension persisted and serial
work-up disclosed leukocytosis, lactic acidosis, increased level of cardiac
enzyme and abnormal ECG with the pressure overload pattern over the
V3 to V6. Chest radiograph showed cardiomegaly and wide
mediastinum especial over the left upper
part ( Figure 1). Ceftriaxone was prescribed. He was admitted to
MICU under the impression of septic shock with cardiovascular dysfunction
on the morning of October 27.
On arrival, his
consciousness was semicoma (Glascow coma scale: E3M4V3
). Blood pressure was 100/60 mmHg and
pulse rate was regular with rate of
80 per minute. Body temperature was
36.5℃. Respiratory rate was 30 per minute
and usage of accessory muscles was noticed. Head and neck were
grossly normal without lymphadenopathy or goiter. Conjunctiva was not
pale and sclera anicteric. Jugular vein was engorged. Breath sound showed
mild bilateral basal crackles. A Grade 2/6 early diastolic
murmur over left sternal border was
auscultated. The abdomen was soft and flat and bowel sound
was normoactive. The extremities were cold without cyanosis and the
peripheral pulsation was intact and symmetric.
Laboratory Data
1. CBC/DC
|
|
WBC
(K/μL) |
RBC
(M/μL) |
HB
(g/dL) |
MCV
(fL) |
PLT
(K/μL) |
Seg
(%) |
Lym
(%) |
Eos
(%) |
|
10/26 |
11.36 |
3.69 |
11.9 |
91.1 |
89.0 |
94.1 |
3.5 |
0.1 |
|
10/27 |
8.86 |
3.52 |
11.0 |
90.3 |
105.0 |
84.6 |
10.7 |
4.2 |
2. ABG
|
|
pH |
PaCO2
(mmHg) |
PaO2
(mmHg) |
HCO3-
(mEq/L) |
B.E
(mEq/L)
|
FiO2
(PEEP) |
Ventilator
Mode |
|
10/27(5am) |
7.27 |
27.3 |
73.8 |
12.1 |
-13.3 |
0.6 |
O2mask |
|
10/27(12am) |
7.43 |
31.4 |
85.2 |
23.7 |
-0.6 |
0.5 (10) |
CMV,
Jusonine 4 amples
given |
3. BCS
|
|
T-Bil
(mg/dL) |
AST
(U/L) |
BUN
(mg/dL)
|
Cre
(mg/dL)
|
CK
(U/L) |
CK-MB
(U/L)
|
Troponin I
(ng/mL) |
|
10/27 |
0.9 |
5240 |
50.0 |
3.1 |
504.0 |
35.0 |
22.4 |
|
|
Na
(mmole/L)
|
K
(mmole/L)
|
Cl
(mmole/L)
|
Mg
(mmole/L)
|
CRP
(mg/dL)
|
LDH
(U/L) |
Lactic acid
(mmole/L) |
|
10/27 |
149.0 |
3.4 |
109.0 |
0.9 |
2.3 |
8320 |
>12 |
4. Coagulation
profile
|
|
PT |
PTT |
|
10/27 |
15.4/12.4 |
42.6/37.1 |
5. Pericardial effusion
|
|
Appearance |
Differential counts |
Total protein
(g/dL) |
LDH
(U/L) |
Glucose
(mg/dL)
|
|
10/27 |
Bloody |
Degenerated cells |
6.4 |
741.0 |
68 |
Clincial course &
treatment
Moderate amount pericardial effusion was noted and
emergent pericardiocentesis was performed with pig-tail
inserted. The blood pressure started to elevate after drainage
of 20mL of bloody pericardial effusion, and then dopamine was
gradually tapered off. He underwent endotracheal intubation
due to acute hypoxemic respiratory failure. Transthoracic
echocardiography disclosed suspected aortic dissection which
was later confirmed by transesophageal echocardiography with
the findings of intimal flap and false lumen over aortic arch.
Emergent operation was performed. The finding of operation was
3x1 cm intima flap over lesser curvature of aortic arch with
aortic root spared. Patient tolerated the procedure well and
regained consciousness after operation. However, hepatic
failure and acute renal failure ensured due to the preceding
event of prolonged shock. He was still hospitalized in the
SICU for management of multiorgan failure.
 案例分析
本案例是一位高血壓病人臨床表現有休克現象，若從休克觀點著手，休克可能有下列幾種(1)分布性(distributire
shock)：如敗血性休克，(2)心因性(cardiogenic shock)：又分成左心、右心、心包膜性及瓣膜性，(3)阻塞性(obstructive shock)
：如肺栓塞、脂肪栓塞症候群，(4)低血容性(hypovolemic
shock)。
本案例由臨床表現可大約作成初步鑑別診斷，因病人沒有明顯出血的表現，因此低血容性休克可排除。病人是否有感染情形無法全部排除，因此急診室先給予抗生素，當證明不是時，可儘快調整治療；由於病人胸部Ｘ光片可看到心臟輪廓擴大，且有較寬的縱隔腔，特別是上縱隔腔，至少要考慮是否有心因性休克；若是左心衰竭，病人會有心因性肺水腫的胸部Ｘ光及肺部聽診表現；若是右心衰竭，病人肺野應是清澈的，但不管是左心或右心衰竭，頸靜脈都是怒張的(JVE)；至於瓣膜性心因性休克在心臟聽診上可聽到雜音及相對應左心或是右心衰竭表現。本案例病人在主動脈區有聽到心舒期雜音，應該考慮是有主動脈瓣問題；心臟擴大可以是心臟腔室擴大或心包膜積水，只要初步用超音波掃描，即可區分。
本案例病人先以敗血性休克及心臟功能失調之診斷住到加護病房，經過初步的診查可看到有心包膜積水，給予抽出少量積液之後，病人血壓即回升，證明為急性心包膜積水，因抽出積液為血色(bloody)，不凝固性(noncoagulable)，應當要考慮惡性心包膜積水或主動脈剝離所致，於是經食道心臟超音波(TEE)掃描，證實有主動脈剝離，病人經緊急手術後，生命徵象穩定下來。
主動脈剝離傳統分類為DeBakey, I、II、III目前簡化成Stanford
classification type A (involve ascending aorta，以外科治療為主)；type B
(not involve ascending
aorta，以內科治療為主)。主動脈剝離是心臟急症，當務之急是要將血壓控制得宜，用Sodium nitroprusside
合併加上beta-adrenergic antagonist 或IV
Labetaol，或其他可以減少心臟收縮力的藥(例如：Central acting drugs)
將血壓控制在收縮壓100-120mmHg，以減少心臟收縮力之降血壓藥物為主，不能單獨使用Nitroprusside，雖可降低血壓，但沒有減少心臟收縮力，則無法減少血流對動脈血管的〝切割力〞Shearing
force，對這種病人仍然有危險。若病人有休克時要高度懷疑是否有剝離而破入心包膜、肋膜腔，此時為心臟外科急症，先可引流少量積液，同時安排緊急外科治療。
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Case Discussion