開始正文之前，明確幾個先提條件，1. 本文討論的是3個月大及以上的兒童；2.有慢性呼吸系統疾病、有免疫缺陷的兒童，不在本文討論所列。3.院內感染的肺炎，也不在討論之列。
簡單的說，本文針對的是大于3月齡且平素健康的兒童，在醫院外部，患有肺炎的應對措施，適合于絕大部分小朋友。
另外，本文依據的是2011年，美國感染學會和美國兒童感染疾病協會所發表的小兒肺炎應對策略。
我們節選幾個比較常見，卻又經常在國內被誤導的幾個問題，展現在此。臨床兒科醫生或小朋友家長，都可以參考，當然，也歡迎大家留言，參與討論。
問題一：什麽樣的情況需要住院？
得了肺炎，或者疑似肺炎，有些情況，醫生會建議小兒進行住院治療，到底哪些情況，患兒是要求住院治療的呢？原文是這樣說的，一共四種情況，證據最充分的是第一條，其他證據不充分。
1. 中重度肺炎，主要由兩個指標反應，即呼吸窘迫和低氧血症。呼吸窘迫，小兒常表現爲呼吸速度過頻（過頻的標准，根據不同年齡的小孩不一樣，比如1-5歲的小朋友，如果呼吸速率超過40次就爲呼吸過頻）、鼻翼煽動、精神異常、呼吸暫停或困難、呼吸時發出咕噜聲等。低氧血症，以周圍血氧飽和度持續低于90%爲准。當然，兒科醫生還會通過體格檢查，獲取更多關于呼吸窘迫的證據，所以有呼吸窘迫和低氧血症，不要猶豫，立即住院，強烈推薦，證據充分。
2. 3-6個月患兒，如果懷疑是細菌感染的社區獲得性肺炎，住院可能會獲益。
3. 如果患兒疑似或者確診感染了毒性較強的細菌，比如社區相關的耐甲氧西林的金色葡萄球菌，應當考慮住院。所以細菌類型也很要緊。
4. 如果肺炎患兒在家照顧不方便，或者不能很好的在家完成治療，複診不方便的話，也建議住院。比如家裏離醫院比較遠等原因。
Children and infants who have moderate to severe CAP, as defined by several factors, including respiratory distress and hypoxemia (sustained saturation of peripheral oxygen [SpO2],,90 % at sea level) should be hospitalized for management, including skilled pediatric nursing care. (strong recommendation; high-quality evidence)
Infants less than 3–6 months of age with suspected bacterial CAP are likely to benefit from hospitalization. (strong recommendation; low-quality evidence)
Children and infants with suspected or documented CAP caused by a pathogen with increased virulence, such as community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) should be hospitalized. (strong recommendation; lowquality evidence)
Children and infants for whom there is concern about careful observation at home or who are unable to comply with therapy or unable to be followed up should be hospitalized (strong recommendation; low-quality evidence)
問題二：疑似肺炎患兒，需要做哪些檢查？
目前的現狀是，如果懷疑肺炎，抽血做血常規和拍胸片基本是標配，真有必要嗎，什麽時候需要做血培養，還有流感病毒檢測意義大嗎？我們一條一條的來說。
血培養：對于門診病人來說，血培養對于正常的患兒來說不是常規必須的檢查項目，原文是這樣說的。但是對于病情無好轉，或者在使用抗生素後，病情加重或者惡化的患兒，還是應該做血培養的。住院肺炎患兒，中重度肺炎，特別是複雜性的肺炎病例，應當行血培養檢查。
Blood cultures should not be routinely performed in nontoxic, fully immunized children with CAP managed in the outpatient setting. (strong recommendation; moderate-quality evidence)
Blood cultures should be obtained in children who fail to demonstrate clinical improvement and in those who have progressive symptoms or clinical deterioration after initiation of antibiotic therapy
Blood cultures should be obtained in children requiring hospitalization for presumed bacterial CAP that is moderate to severe, particularly those with complicated pneumonia. (strong recommendation; low-quality evidence)
血常規：所有門診疑似肺炎患兒，沒有必要做血常規檢查。只有那些較重的病例，才考慮做血常規。請見原文：
Routine measurement of the complete blood cell count is not necessary in all children with suspected CAP managed in the outpatient setting, but in those with more serious disease it may provide useful information for clinical management in the context of the clinical examination and other laboratory and imaging studies.
流感病毒或者其他病毒檢測：建議所有社區獲得性肺炎患兒，都需進行流感病毒和其他呼吸病毒檢測，因爲如果病毒檢測是陽性的話，可以減少其他化驗和檢查，同時也會避免抗生素的使用。原文如下：
Sensitive and specific tests for the rapid diagnosis of influenza virus and other respiratory viruses should be used in the evaluation of children with CAP. A positive influenza test may decrease both the need for additional diagnostic studies and antibiotic use, while guiding appropriate use of antiviral agents in both outpatient and inpatient settings. (strong recommendation; high-quality evidence)
胸片：1）門診病例：如果能夠在門診就可以治療的患兒，可以不用拍胸片，來確診是不是肺炎。另外，如果門診肺炎已經開始治療了，但是效果不好，或是有低氧血症或者呼吸窘迫，那麽就需要拍胸片。2）住院病例：所有住院病例，都應當行胸片檢查。3）複查：如果肺炎恢複的很順利，無需常規複查胸片。
Routine chest radiographs are not necessary for the confirmation of suspected CAP in patients well enough to be treated in the outpatient setting.
Chest radiographs (posteroanterior and lateral) should be obtained in all patients hospitalized for management of CAP.
Repeated chest radiographs are not routinely required in children who recover uneventfully from an episode of CAP.u
參考文獻：
John S. Bradley,1,a Carrie L. Byington,et al,The Management of Community Acquired Pneumonia in Infants and Children Older Than 3 Months of Age: Clinical Practice Guidelines by the Pediatric Infectious Diseases Society and the Infectious Diseases Society of AmericaClinical Infectious Diseases 2011;53(7):e25–e76