pulsatile flow

Despite numerous studies on tissue perfusion, capillary circulation, and their related factors, there is still no consensus on the utilization of pulsatile versus non-pulsatile perfusion methods to provide proper perfusion in patients undergoing Coronary Artery Bypass Graft (CABG) surgery.

This study aimed to compare the effects of pulsatile versus non-pulsatile perfusion methods on renal function in patients undergoing CABG surgery in Shahid Mohammadi hospital, Bandar Abbas, Iran in 2018.

In this randomized clinical trial, 50 patients aged > 18 years who underwent CABG surgery were randomly divided into a pulsatile and a non-pulsatile group (n = 25 in each group). The two groups were compared in terms of laboratory findings including the plasma levels potassium, sodium, creatinine, and blood urea nitrogen, Glomerular Filtration Rate (GFR), urinary output, and ejection fraction.

The results revealed a significant difference between the two groups regarding the trend of GFR changes during the study (P = 0.01). Accordingly, postoperative GFR increased more in the pulsatile group than in the non-pulsatile group. Moreover, creatinine and blood urea nitrogen levels reduced in the pulsatile group compared to the baseline. However, no significant differences were observed in the mean levels of potassium, sodium, and creatinine, urinary output, and ejection fraction in the two groups before and after the surgery.

According to the results, pulsatile method was preferred to the nonpulsatile perfusion method due to its positive effects on creatinine and blood urea nitrogen levels as well as on GFR during and after the CABG surgery.

Peripheral intravenous catheters (PICs) patency techniques such as flushing are being developed. According to some studies, flushing can be used continuously or in pulsatile forms. This study aimed to compare the effects of pulsatile flushing (PF) and continuous flushing (CF) on time and type of PICs patency.

In this double-blind randomized clinical trial, 71 patients were randomly assigned into two groups of PF (n=35) and CF (n=36). The PF protocol was performed as successive injections of 1 mL normal saline (N/S) per second (sec) with a delay of less than 1 sec until the completion of 5 mL of solution. However, CF protocol was performed by injecting 5 mL N/S within 5 sec without any delay before and after each medicine administration. Data related to the time and type of PICs patency were collected using a patency checklist every 12 hours (h) up to 96 h. The statistical analysis was done by R statistical software (Version 3.5.1).

The results showed that the number of PICs remaining open was not significantly different between PF and CF groups during 96 h. The highest number of PICs excluded from the study was related to the time of 96 h as a result of partial patency in the two groups.

There was no difference between CF and PF regarding the time and type of PICs patency. Thus, both techniques can be used to maintain the catheter patency.