網路內科繼續教育
有效期間:民國 91年01月16日 91年01月31日

    Case Discussion

A 67 year-old woman visited our ER due to remittent fever and progressive dyspnea for three days.

<Brief History>
     The patient was in good health and exercise capacity. She started to have cough with mild whitish sputum, headache with low back pain and poor appetite since the night of October 11, 2001; she didn't pay much attention to it. Fever with chills developed on October 12. Common cold was impressed initially by LMD. On account that spiking fever (up to 40°C) developed on October 15, she visited a community hospital where leukocytosis was noted, but no definite infectious focus was told. She was treated with oral medication. The fever persisted with progressive dyspnea; she was taken to ER in a university hospital on October 15. The work-up at ER included: ECG showed normal sinus rhythm and chest radiograph disclosed a patchy lesion (Figure 1 ). Empirical antibiotic (Ampicillin with sulbactam) was given under the impression of community-acquired pneumonia. She was admitted to general ward for further care. Tracing back the history, she lived in downtown and denied history of travelling to other country in recent one year. No pet raising or drug history including herbs were noted preceding this event. On examination, the blood pressure was 160/90 mmHg and regular pulse rate 100 beats per minute. The body temperature was 40℃ and respiratory rate 26 per minute. The conjunctiva was not pale and the sclera was anicteric. There was no neck lymphadenopathy or goiter palpable. The jugular vein was flat. Chest auscultation showed coarse crackles over bilateral lower lung fields and bronchial sound over right lower lung. The heart sound was regular without murmur. The abdomen was soft and bowel sound was normoactive. Bilateral lower limb edema was found. No skin rash nor eschar was found over body surface area.

<Laboratory Data>

1. CBC/DC
 

WBC
(K/μL)

RBC
(M/μL)

HB
(g/dL)

MCV
(fL)

PLT
(K/μL)

Seg
(%)

Lym
(%)

Eos
(%)

10/15

10.96

3.46

11.1

93.4

216

90

3.5

0.1

10/19

14.55

4.04

12.3

88.6

235

89.4

4.7

1.6

 2. ABG
 

pH

PaCO2
(mmHg)

PaO2
(mmHg)

HCO3-
(mEq/L)

B.E
(mEq/L)

FiO2

Ventilator
Mode

10/15

7.42

31.5

77.0

19.8

-3.7

0.3

nasal cannula 5 L/min

10/19

7.38

45.5

62

21

-2.5

1.0

Mechanical ventilation

3. BCS
 

BUN
(mg/dL)

Cre
(mg/dL)

Na
(mmole/L)

K
(mmole/L)

AST
(U/L)

ALT
(U/L)

CRP
(mg/dL)

10/15

19.1

0.56

135.8

3.68

26

30

 

10/19

 

 

137.0

4.0

58

24

 >12

4. Coagulation profile
 

PT

PTT

10/19

14.7/12.4

42.6/37.1

5. Serologic examination
 

Legionella urinary Ag

Chlamydia pneumoniae Ag

Mycoplasma
pneumoniae IgM

10/17

positive

   

10/21

 

negative 

negative

<Clincial course & treatment>

      Fever persisted under ampicillin with sulbactam. Hypoxemia progressed, and the O2 demand increased gradually. Desaturation with drowsy consciousness was noted on October 17; she was intubated and transferred to ICU. Atypical pneumonia was suspected, because sputum smear showed much PMN without bacteria. Antibiotic was shift to Ciprofloxacin for coverage of legionella infection. Chest computed tomography (Figure 2 ) showed dense pneumonic patch. Refractory hypoxemia ensured on October 19 under mechanical ventilation with FiO2 1.0 (PaO2/FiO2 <200). Chest radiograph deteriorated to bilateral diffuse infiltrates. Swan-Ganz catheter was inserted and the results disclosed good LV function. Prone position was tried with improvement of oxygenation . Under the impression of acute respiratory distress syndrome and well control of infection, methylprednosolone 160 mg/day was given since October 24. The oxygenation improved and FiO2 can be tapered gradually. Extubation was performed on October 28. She was transferred to general ward and discharged on November 9, 2001 without any sequelae.

案例分析

本案例是一位社區性肺炎的病人,而後惡化為急性呼吸窘迫症候群,其疾病過程可分成以下幾個部份:

1. 有關社區性肺炎的部份:我們必須區分是典型或非典型,本案例比較像是非典型,因(1)病人痰液檢查可見到許多發炎細胞,但是卻看不到有細菌,(2)病人的白血球是相對的偏低,(3)病人的心跳在發燒的情況下是相對的偏低,(4)病人胸部X光片是多個肺葉的肺炎,(5)病人痰液外觀上呈現白稠,而不是傳統的黃濃稠。

2. 病人治療中一度有低血氧的情況,這時候不管是如何調整呼吸器,都沒有辦法提高血氧含量,此時我們必須考慮到是否有一些情況發生:
(1)急性肺栓塞:因為是急性發生,會造成右心衰竭,血壓下降,心臟超音波可見右心室脹大,收縮不良,此病人並沒有這些表現。
(2)心因性肺水腫:病人可能因敗血症,而引起左心室衰竭,使氧氣交換惡化,此病人經放置順流導管(Swan-Ganz catheter),排除此原因。
(3)極嚴重的肺炎:這位病人是屬於這一項原因,以X光片及CT片來看,右肺有非常密緻的肺實質變化。

3.病人肺部情況進入急性肺損傷/急性呼吸窘迫症候群(Acute lung injury/Acute respiratory distress syndrome)的階段後,我們採用了一些治療的策略:
(1)呼吸器的設定調整為低潮氣容積及高吐氣末正壓呼吸(Low tidal volume and high PEEP)以避免呼吸器引起的肺損傷。
(2)使用俯臥姿式(Prone position),目的是為改善肺部通氣與灌流的均衡,以提升氧含量。
(3)使用類固醇,為了改善肺部發炎的狀況,可以縮短病人使用呼吸器的時間,及加護病房的住院天數。

4. 急性呼吸窘迫症候群病人,其預後主要不在於肺部本身嚴重度,而在於整個疾病過程病人器官衰竭之情形,即使經過妥善的照顧,病人仍然有40~60 %死亡率。

繼續教育考題
1.
(B)
本案例是屬於何種型式的肺炎?
A社區性典型(Typical community-acquired)
B社區性非典型(Atypical community-acquired)
C院內性典型(Typical hospital-acquired)
D院內性非典型(Atypical hospital-acquired)
2.
(A)
承上題,選擇其答案的理由,何者為非?
A痰液檢查有許多發炎細胞,可見到細菌非常多
B多肺葉的肺炎
C心跳與體溫之間無正常相對關係(relative bradycardia)
D痰液外觀上呈現白稠,而不是傳統的黃濃稠
3.
(D)
本案例給予抗生素治療,是給予何種抗生素,其主要針對是何類細菌?
APenicillin → pneumococcus
BCeftazidime → Pseudomonus spp.
CVancomycin → Methicillin-resistant staphylococcus aureus
DCiprofloxacin → Legionella spp.
4.
(D)
病人治療過程中,血氧量一度惡化,其原因為:
A急性肺栓塞(Acute pulmonary embolism)
B急性心肌梗塞(Acute myocardial infarction)
C張力性氣胸(Tension pneumothorax)
D肺炎惡化
5.
(D)
針對治療急性肺損傷/急性呼吸窘迫症候群,呼吸器的調整以下何者正確?
A使用高潮氣容積(Tv),高的吐氣末正壓(PEEP)
B使用低Tv,低的PEEP
C使用高Tv,低的PEEP
D使用低Tv,高的PEEP
6.
(C)
由剛入院病人X光片(Figure 1)及CT片 (Figure 2 )可見病人肺炎的範圍主要在?
A右上葉
B右中葉
C右下葉
D平均分佈左右兩肺葉
7.
(A)
針對治療急性肺損傷/急性呼吸窘迫症候群,使用類固醇的目的,以下何者為是?
A減緩肺部發炎反應,改善氧合程度
B減緩病人呼吸道支氣管痙攣的程度
C減緩病人呼吸功
D減緩病人二氧化碳產生量
8.
(B)
急性呼吸窘迫症候群臨床診斷須符合以下條件,何者為非?(請參考本案例所提示之內容)
A血氧含量不佳(PaO2/FiO2<200)
BX光片表現可以是單側肺部浸潤
C引起之原因可以是直接或間接肺損傷引起
D必須排除是因為心臟衰竭所引起之臨床表現
9.
(C)
急性呼吸窘迫症候群之病人其預後與何項因素最有相關?
A呼吸器使用時間之長短
B呼吸器是否早期使用
C病人多重器官衰竭的數目
D病人是否有使用強心劑
10.
(D)
急性呼吸窘迫症候群其病因,以下何者為是?
A吸入性肺炎(Aspiration pneumonia)
B輸血(Transfusion related acute lung injury)
C急性脂肪性栓塞(Acute fat embolism)
D以上皆是

答案解說
  1. 由本案例之痰液檢查,多肺葉肺炎,相對心率變慢及痰液之外觀,而知為社區性非典型肺炎。
  2. 同1. 之解答。
  3. 一般來說若懷疑有Legionella infection,可給予Ciprofloxacin或Erythromycin治療。
  4. 病人治療過程中,由於肺炎持續惡化使得血氧持續低下,而後進入急性呼吸窘迫症候群。
  5. 對於急性呼吸窘迫症候群的治療,其呼吸器的調整,目前的共識是使用低潮氣容積及高的吐氣末正壓。
  6. 配合胸部X光片及CT片,病人一開始主要為右下肺葉的肺炎。
  7. 急性呼吸窘迫症候群,使用類固醇的時機,是在晚期的階段,且在沒有嚴重感染的情況下。
  8. 急性呼吸窘迫症候群的診斷有(1)低血氧含量(PaO2/FiO2<200) (2)胸部X光片為瀰漫兩側浸潤變化 (3)沒有心臟衰竭引起之變化
  9. 急性呼吸窘迫症候群之病人預後最主要的決定因素是病人器官衰竭的數目。
  10. 急性呼吸窘迫症候群的原因可分為直接或間接的肺損傷,可以有(1)吸入性肺炎 (2)敗血症 (3)急性胰臟炎 (4)輸血引起 (5)急性脂肪栓塞 (6)外傷


Top of Page