You will be provided with the titles and abstracts of a collection of medical RCT reports studying a clinical question -- for instance, the efficacy of an intervention on some medical outcome. Please write a few sentences synthesizing the findings of these reports, which could serve as a conclusion section for a systematic review article. Your response should not include any other text. The RCT reports are below.



Title 1:
Guillain-Barré syndrome: quantitative measurement of plasma exchange therapy.
Abstract 1:
A prospective, controlled study with quantitative measurement of hand muscle-force for plasma exchange treatment in acute Guillain-Barré polyradiculitis was done. Of the 29 patients with severe symptoms, every second patient was selected to the plasma exchange group and all others to the control group. The muscle forces increased and CSF protein decreased significantly more in the plasma exchange group than in the control group, but there were no differences in hospitalization or recovery periods.


Title 2:
Appropriate number of plasma exchanges in Guillain-Barré syndrome. The French Cooperative Group on Plasma Exchange in Guillain-Barré Syndrome.
Abstract 2:
Plasma exchange (PE) is the standard treatment in Guillain-Barré syndrome (GBS) patients who have lost the ability to walk. The effect of exchanges before this stage and the optimal number of exchanges for the other patients are still unknown. We randomized 556 GBS patients according to severity and number of exchanges as follows: Zero versus 2 PEs for patients who could walk-with or without aid-but not run, or who could stand up unaided (mild group); 2 versus 4 PEs for patients who could not stand up unaided (moderate group); and 4 versus 6 PEs for mechanically ventilated patients (severe group). In the mild group, 2 PEs were more effective than none for time to onset of motor recovery (median, 4 vs 8 days, respectively). In the moderate group, 4 PEs were more beneficial than 2 for time to walk with assistance (median, 20 vs 24 days) and for 1-year full muscle-strength recovery rate (64% vs 46%). Six PEs were no more beneficial than 4 in the severe cases. Patients with mild GBS on admission should receive 2 PEs. Patients with moderate and severe forms should benefit from 2 further exchanges.


Title 3:
Efficiency of plasma exchange in Guillain-Barré syndrome: role of replacement fluids. French Cooperative Group on Plasma Exchange in Guillain-Barré syndrome.
Abstract 3:
The goals of this multicenter controlled trial were: (1) to study the short-term effect of plasma exchange in the Guillain-Barré syndrome when applied alone within 17 days of onset of the disease; and (2) to compare two replacement fluids, diluted albumin and fresh frozen plasma (FFP) with regard to efficacy and morbidity. Two hundred twenty patients were included, 111 in the control group, 109 in the plasma exchange group, 57 of whom were assigned to receive albumin and 52 to receive fresh frozen plasma. Treatment consisted of four plasma exchanges of two plasma volumes each, initiated on the day of randomization and repeated on alternate days. Significant short-term benefits appeared in the group that received plasma exchange as demonstrated by the reduction in the proportion of patients who required assisted ventilation after randomization, and the decrease in time before beginning weaning from ventilator, time to onset of motor recovery, and time to walk with and without assistance. No statistically significant difference was found between the group that received albumin and the group that received fresh frozen plasma. Incidents during exchanges and complications related to the plasma exchange were more frequent in patients who received fresh frozen plasma. Plasma exchange is beneficial in Guillain-Barré syndrome when it is carried out early in the course of the disease. Given its risks and the lack of its clear superiority over albumin, however, we recommend that fresh frozen plasma be abandoned in the treatment of Guillain-Barré syndrome.


Title 4:
Beneficial effects of plasma exchange in acute inflammatory polyradiculoneuropathy.
Abstract 4:
The results of a controlled trial in which 38 patients with severe acute inflammatory polyradiculoneuropathy took part indicate that plasma exchange favourably influenced the course of the disease. Significant benefits were seen in time until onset of improvement, course of muscular weakness, improvement in disability grades over the first 2 months, and working capacity after 1 month. Cost-benefit analysis showed that the exchange treatment resulted in net financial savings. The results suggest that plasma exchange may have a role in the treatment of severe acute inflammatory polyradiculoneuropathy.
Moderate-quality evidence shows significantly more improvement with plasma exchange than supportive care alone in adults with Guillain-Barré syndrome without a significant increase in serious adverse events. There was a small but significant increase in the risk of relapse during the first six to 12 months after onset in people treated with plasma exchange compared with those that were not treated. Despite this, after one year, full recovery was significantly more likely and severe residual weakness less likely with plasma exchange.