Mediastinal chest drain clearance for cardiac surgery.
BACKGROUND
Cardiac tamponade may occur following cardiac surgery as a result of blood or fluid collecting in the pericardial space compressing the heart and reducing cardiac output. Mediastinal chest drains (including pericardial drains) are inserted as standard post-operative practice following cardiac surgery to assist the clearance of blood from the pericardial space and to prevent cardiac tamponade. To prevent chest tubes from blocking and so causing tamponade nurses manipulate them to prevent or remove clots. Manipulation methods including milking, stripping, fanfolding and tapping may be applied to the tubes to keep them from blocking. Evidence is required as to the safest and most effective means of preventing chest tube blockage and preventing cardiac tamponade.


OBJECTIVE
To compare different methods of chest drain clearance (i.e. varying levels of suction or suction in combination with milking, stripping, fanfolding and tapping of chest drains) in preventing cardiac tamponade in patients following cardiac surgery.


METHODS
Over both the initial review and the 2004 revision, we searched the Cochrane Heart Group trials register, the Cochrane Controlled Trials Register (CCTR) (Issue 4, 2003) The Cochrane Database of Systematic Reviews (CDSR), the Database of Abstracts of Reviews of Effectiveness (DARE), Issue 4, 2003, MEDLINE (1966 to Nov Week 2, 2003), EMBASE (1980 to 2003 Week 47), CINAHL (1982 to Nov 2003), the Clinical Trials site of the NIH, (USA) (24.11.03) and reference lists of articles.


METHODS
Randomised, quasi-randomised or systematically allocated clinical trials of chest tube manipulation methods in adults and children with mediastinal chest drains following cardiac surgery were included.


METHODS
Two reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information where required. Adverse effects information was collected from the trials.


RESULTS
Three studies with a total of 471 participants were included. There was no data, however, which could be included in a meta-analysis. This was due to inadequate data provision by two of the studies. Where adequate data were provided there were no common interventions or outcomes to pool. On the basis of single studies there was no evidence of a difference between groups on incidence of chest tube blockage, heart rate, cardiac tamponade or incidence of surgical re-entry.


CONCLUSIONS
There are insufficient studies which compare differing methods of chest drain clearance to support or refute the relative efficacy of the various methods in preventing cardiac tamponade. Nor can the need to manipulate chest drains be supported or refuted by results from RCT's.
Wallen
M
M
Morrison
A
A
Gillies
D
D
O'Riordan
E
E
Bridge
C
C
Stoddart
F
F
D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D002305:Cardiac Tamponade / Q000517:prevention & control*; D015505:Chest Tubes; D004322:Drainage; D006801:Humans; D011183:Postoperative Complications / Q000517:prevention & control*; D016032:Randomized Controlled Trials as Topic