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Three Part Question

In [a patient who has sustained blunt trauma who is found to have an occult pneumothorax on CT scan] is [tube thoracostomy better than observation] at reducing [morbidity and mortality]?

Clinical Scenario

A 30 year old man is brought into the Emergency Department after a road traffic accident. A chest X-ray taken as part of the ATLS trauma series is normal and he has no clinical signs of chest injury. He goes on to have an abdominal CT for investigation of blunt abdominal trauma. This reveals an occult pneumothorax. You wonder whether you should insert a chest drain.

Search Strategy

Medline 1966 to October Week 4 2005 using the OVID interface.
Embase 1980 to 2005 week 47
The Cochrane Library Issue 4 2005
Medline:[exp pneumothorax/ or pneumothorax.mp] AND ([exp "wounds and injuries"/OR trauma.mp] OR chest drain.mp OR exp chest tubes/ OR exp thoracostomy]) AND ([exp Tomography, X-ray computed OR CT.mp] OR occult.mp) LIMIT to human AND English
Embase:exp pneumothorax/or pneumothorax.mp.] AND [exp injury/or exp wound/ or trauma.mp. or exp thorax drainage/or chest drain.mp. or thoracostomy.mp.] AND [exp computer assisted tomography/ or CT.mp. or exp occult blood/] Limit to human and English, Age groups - All adult 18–64 years and 64 years >
Cochrane:Chest drains [MeSH] AND pneumothorax [MeSH] 23 hits

Search Outcome

Altogether 279 papers were found of which 273 were irrelevant or of insufficient quality for inclusion

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Garramone et al 1991 USA	26 trauma patients aged 14-65 with occult pneumothorax (OPTX) on abdominal CT. Classified as <5x80mm or >=5x80mm	Retrospective chart review	Complications of PTX, respiratory or haemodynamic compromise	No patient had haemodynamic or respiraory complications. Of 18 with small OPTX who were observed 2 had chest drains for increasing subcutaneous emphysema, 1 for increasing PTX. 10 were ventilated. Of 13 pateints with larger OPTX 10 were ventilated. 4 had prophylactic chest drains, 3 for increasing subcutaneous emphysema 2 for increasing effusion	Retrospective Small numbers
Collins et al 1992 USA	26 patients aged 18-82 with occult pneumothorax Immediate chest tube (n=12) vs observation (n=11)	Retrospective chart review	Length of hospital stay (mean)	13.4 days vs 8.8 days	Small study Retrospective
			Length if ICU stay	6.3 days vs 3.3 days
			Complications	immediate chest tube group : 1 pt had laceration of intercostal artery, 1 self removed and needed replacement for recurrent pneumothorax. 2 observed pts had eventual chest tubes for enlarging pneumothorax or haemothorax
Enderson et al 1993 USA	40 adult trauma patients Randomized to immediate chest tube (n=19) or observation (n=21)	PRCT	Length of hospital stay	12.9 vs 17.6 days	Small study
			Length of ICU stay	2.8 vs 3.2 days
			Complications	immediate chest tube: 1 pneumonia, 8 atelectasis. Observation group 3 tension pneumothorax, 5 progression pneumothorax, 1 pneumonia, 1 empyema, 3 atelectasis
Wolfman et al 1998 USA	44 pts aged 17 months -70 yrs with occult pneumothorax, classified according to siza into miniscule, anterior or anterolateral. Chest tube inserted dependent on size and at trauma surgeons discretion	Prospective non-randomized	Complications	15/16 with miniscule observed, 2 had delayed chest drain for pneumothorax progression. 12/20 anterior observed 1 developed tension pneumothorax. 8 with anterolateral had immediate chest drain, no complications	Small numbers Both adults and children
Brasel et al 1999 USA	39 adult patients with occult pneumothorax randomised to chest tube (n=18) or observation (n=21)	PRCT	Respiratory distress	1 pt with chest tube was intubated for stridor. 3 observed pts had resp distress with pneumothorax progression	only 39 of 86 eligible pts recruited
Holmes et al 2000 USA	11 children <16yrs with occult pneumothorax presenting to level 1 trauma centre. 1 had chest tube, 10 observed	Prospective observational cohort study	Complications	no haemodynamic or respiratory complications	small numbers paediatric population

Comment(s)

All the papers report small numbers. There are conflicting results. Some classify occult pneumothoraces into size but different techniques are used

Clinical Bottom Line

It appears reasonable to treat small occult pneumothoraces with observation, there is no evidence whether it is safe to extend this to larger occult pneumothoraces.

References

1. Garramone RR Jr. Jacobs LM. Sahdev P. An objective method to measure and manage occult pneumothorax. Surgery, Gynecology & Obstetrics 1991:173(4);p257-261.
2. Collins JC, Levine G, Waxman K. Occult traumatic pneumothorax : immediate tube thoracostomy vs expectant management. American Surgeon 1992:58(12);743-6.
3. Enderson BL. Abdalla R. Frame SB. Casey MT. Gould H. Maull KI. Tube Thoracostomy for occult pneumothorax: a prospective randomized study of its use. The journal of Trauma-Injury Infection & Critical Care 1993:35(5);726-30.
4. Wolfman NT. Myers WS. Glauser SJ. Meredith JW. Chen MY. Validity of CT classification on management of occult pneumothorax. American Journal Roentgenology 1998:171(5);1317-20.
5. Brasel KJ. Stafford RE. Weigelt JA. Tenquist JE. Borgstrom DC. Treatment of Occult Pneumothoraces from blunt trauma. The Journal of Trauma, Injury, Infection and Critical Care 1999:46(6);987-990.
6. Holmes JF. Brant WE. Bogren HG. London KL. Kuppermann N. Prevalence and Importance of Pneumothoraces Visualised on Abdominal CT scan in children with blunt trauma. Journal of Trauma, injury, infection and critical care 2000:50(3);516-520.