New and updated Cochrane summaries

Background

Patients with cancer undergoing surgical procedures are at an increased risk of blood clots. The blood thinner administered to prevent these clots can be either an unfractionated heparin (UFH) or low molecular weight heparin (LMWH). These two blood thinners may have different effectiveness and safety profiles.

Study characteristics

We searched scientific databases for clinical trials looking at the effects of UFH and LMWH on death, pulmonary embolism (blood clot in the lungs), deep vein thrombosis (blood clot in the veins of the legs), bruising, bleeding, and need for blood transfusion in patients having operations. We included people of any age or sex. The evidence is current to February 2013.

Key results

We found 16 studies of 12,890 patients with cancer. There was no evidence to show that LMWH was better than UFH for death, asymptomatic deep vein thrombosis, pulmonary embolism, or bleeding. There was less bruising around the wound and more blood transfusion during the operation with LMWH compared with UFH. Further trials are needed to clarify the effectiveness of LMWH and UFH.

Quality of evidence

The overall quality of evidence of these studies was moderate.

Platinum-based chemotherapy, including cisplatin, carboplatin or oxaliplatin, or a combination of these, is used to treat different types of childhood cancer. Unfortunately, one of the most important adverse effects of platinum chemotherapy is hearing loss. This can occur not only during treatment but also years after the end of treatment. Although it is not life-threatening, the loss of hearing, especially during the first three years of life, may lead to difficulties with school performance and psychosocial functioning. Therefore, prevention of platinum-induced hearing loss is very important and might improve the quality of life of children undergoing cancer treatment and those who have survived treatment with platinum-based chemotherapy.

The review authors identified one randomised study comparing a continuous cisplatin infusion with a one hour cisplatin bolus infusion in children with neuroblastoma. For the continuous infusion, cisplatin was administered on days 1 to 5 of the treatment cycle but it is not clear if the infusion duration was a total of 5 days. The study had methodological problems and only results from shortly after induction therapy were available. At the moment there is no evidence showing that the use of a different cisplatin infusion duration prevents hearing loss or adversely affects tumour response and adverse effects. No data were available for the other outcomes of interest (i.e. tinnitus, overall survival, event-free survival and quality of life) or for other (combinations of) infusion durations or other platinum analogues. We need more high quality research before definite conclusions can be made about the usefulness of different platinum infusion durations to prevent hearing loss in children with cancer.

This review, carried out by authors of the Cochrane Oral Health Group, has been produced to assess the effects of antibiotics on pain and swelling in two conditions commonly responsible for causing dental pain when given with or without dental treatment (such as extraction, drainage of a swelling or root canal treatment).

Background

Dental pain is a common problem and can arise when the nerve within a tooth dies due to progressing decay or severe trauma. The tissue around the end of the root then becomes inflamed and this can lead to acute pain, which gets worse on biting. Without treatment, bacteria can infect the dead tooth and cause a dental abscess, which can lead to swelling and spreading infection that may be life threatening.

The recommended treatment of this form of toothache is the removal the dead nerve and associated bacteria. This is usually done by dental extraction or root canal treatment. Antibiotics should only be prescribed when there is severe infection that has spread from the tooth. However, some dentists still routinely prescribe oral antibiotics to people with acute dental conditions that have no signs of spreading infection.

Minimising inappropriate antibiotic prescribing is plays a key role in limiting the development of antibiotic-resistant bacteria. Since dentists prescribe approximately 8% to 10% of all primary care antibiotics in developed countries, dental prescribing may contribute to antibiotic resistance. Therefore, it is important that antibiotics should only be used when they are clinically beneficial for the person.

Study characteristics

The evidence on which this review is based was up to date as of 1 October 2013. We searched scientific databases and found two trials, with a 62 participants included in the analysis. Both trials were conducted at university dental schools in the USA and evaluated the use of oral antibiotics in the reduction of pain and swelling reported by adults after having the first stage of root canal treatment under local anaesthetic. The antibiotic used in both trials was penicillin VK and all participants also received painkillers.

Key results

The two studies included in the review reported that there were no clear differences in the pain or swelling reported by participants who received oral antibiotics compared with a placebo (a dummy treatment) when provided in conjunction with the first stage of root canal treatment and painkillers, but the studies were small and we could not exclude potentially important differences between groups. Neither study examined the effect of antibiotics delivered by themselves, without dental treatment.

One trial reported side effects among participants: one person who received the placebo medication had diarrhoea and one person who received antibiotics experienced tiredness and reduced energy after their operation.

Quality of evidence

We judged the quality of evidence to be very low. There is currently insufficient evidence to be able to determine the effects of antibiotics in these conditions.