The insertion of a lumbar puncture needle or epidural catheter may be associated with peri- and post-procedural bleeding. People who require this procedure may have disorders of coagulation as a result of their underlying illness, co-morbidities or the effects of treatment. Clinical practice in some institutions is to mitigate the risk of bleeding in these patients by prophylactically transfusing plasma in order to correct clotting factor deficiencies prior to the procedure. However, plasma transfusion is not without risk, and it remains unclear whether this intervention is associated with reduced rates of bleeding or other clinically-meaningful outcomes.

To assess the effect of different prophylactic plasma transfusion regimens prior to insertion of a lumbar puncture needle or epidural catheter in people with abnormal coagulation.

We searched for randomised controlled trials (RCTs), non-randomised controlled trials (non-RCT) and controlled before-after studies (CBAs) in CENTRAL (the Cochrane Library 2016, Issue 11), MEDLINE (from 1946), Embase (from 1974), CINAHL (from 1937), the Transfusion Evidence Library (from 1950), and five other electronic databases as well as ClinicalTrials.gov and World Health Organization International Clinical Trials Registry Platform (ICTRP) for ongoing trials to 9 January 2017.

We planned to include RCTs, non-RCTs, and CBAs involving transfusions of plasma given to prevent bleeding in people of any age with a coagulopathy requiring insertion of a lumbar puncture needle or epidural catheter. If identified, we would have excluded uncontrolled studies, cross-sectional studies and case-control studies. We would only have included cluster-RCTs, non-randomised cluster trials, and CBAs with at least two intervention sites and two control sites. In studies with only one intervention or control site, the intervention (or comparison) is completely confounded by study site making it difficult to attribute any observed differences to the intervention rather than to other site-specific variables.

We planned to exclude people with haemophilia as they should be treated with the appropriate factor concentrate. We also planned to exclude people on warfarin as guidelines recommend the use of prothrombin complex concentrate for emergency reversal of warfarin.

We used standard methodological procedures expected by Cochrane.

We identified no completed or ongoing RCTs, non-RCTs, or CBAs.

There is no evidence from RCTs, non-RCTs, and CBAs to determine whether plasma transfusions are required prior to insertion of a lumbar puncture needle or epidural catheter, and, if plasma transfusions are required, what is the degree of coagulopathy at which they should be given. We would need to design a study with at least 47,030 participants to be able to detect an increase in the number of people who had bleeding after lumbar puncture or epidural anaesthetic from 1 in 1000 to 2 in 1000.

Review question
We evaluated the evidence about whether people with abnormal coagulation (poor blood clotting) require a plasma transfusion prior to insertion of a lumbar puncture needle or epidural catheter, and if so what is the degree of abnormal coagulation at which a plasma transfusion is required.

Background
People with abnormal coagulation may require a lumbar puncture or epidural anaesthesia. A lumbar puncture is usually performed by inserting a needle between the bones (vertebrae) of the spine in the lower back into the fluid surrounding the spinal cord (the bundle of nerves that runs down the spine and connects the brain with the body). Lumbar punctures are performed either to obtain a sample of this fluid or to administer treatment into the fluid (chemotherapy or an anaesthetic). The lumbar puncture needle is removed immediately after any fluid samples have been taken or treatment has been administered. An epidural involves inserting a larger diameter needle than a lumbar puncture needle. The epidural needle passes through the same tissues as the lumbar puncture needle but stops short of penetrating the sac of fluid surrounding the spinal cord. Instead any treatment is injected into the space just outside the sac of fluid (called the epidural space). A small tube (an epidural catheter) is often passed through the epidural needle and left in position so that additional local anaesthetic medicines can be given. Current practice in many countries is to give plasma transfusions to prevent serious bleeding due to the procedure if blood tests to assess clotting are abnormal. Although the risk of bleeding appears to be very low, if bleeding does occur, it can be very serious. Correction of clotting abnormalities with a plasma transfusion is not without risks of its own, and it is unclear whether this practice is beneficial or harmful. People may be exposed to the risks of a plasma transfusion without any obvious clinical benefit. The risk that a plasma transfusion can cause serious harm, such as transmission of an infection or severe breathing problems, is very low.

Study characteristics
We searched scientific databases for clinical studies (randomised controlled trials and well designed non-randomised studies) of people of any age with abnormal coagulation requiring a lumbar puncture or epidural anaesthesia. The evidence is current to 9 January 2017. In this review, we found no relevant studies.

Key results
There are no results because we found no relevant studies. The risk from bleeding after a lumbar puncture or epidural is very low and a very large study (with approximately 50,000 people) would be needed to know whether giving plasma transfusions before having these procedures is helpful.

Quality of the evidence

We did not assess the quality of the evidence because there were no included studies.