Assessing the Influence of Insulation on Intravenous Fluid Infusion Temperature

Abstract

Objectives: Inducing therapeutic hypothermia using chilled saline in resuscitated cardiac arrest patients has been shown to be feasible and effective. Limited research exists assessing the efficiency of this cooling method. The objective of this study was to assess the change in temperature of 4°C saline upon exiting an infusion set in the laboratory setting while varying conditions of fluid delivery.Methods: Efficiency was studied by assessing change in fluid temperature (°C) during the infusion under four laboratory conditions. Each condition was performed four times using 1-L bags of normal saline. Fluid was infused into a 1000-mL beaker through 10 gtt/mL tubing. Flow rate was controlled using a tubing clamp and in-line transducer with a flow meter, while temperature was continuously monitored in a side port at the terminal end of the intravenous (IV) tubing using a digital thermometer. The four conditions included different insulation methods. Descriptive statistics and analysis of variance were performed to assess changes in fluid temperature.Results: The mean (±SD) fluid temperature at time 0 was 3.2°C (95% confidence interval [CI] = 3.0 to 3.4°C) with no significant difference in starting temperature between groups (p = 0.45). When flow rate was constant, it was determined that fluid temperatures were significantly cooler when infused using a chilled, gel-filled sleeve around the saline bag (p < 0.006). Conclusions:In a laboratory setting, the most efficient method of infusing cold fluid appears to be a method that both keeps the bag of fluid insulated and infused at a faster rate.ACADEMIC EMERGENCY MEDICINE 2012; 19:1309-1312 © 2012 by the Society for Academic Emergency Medicine S everal studies have investigated the effectiveness of chilled saline for the induction of therapeutic hypothermia; however, there is scant research describing the most efficient method for delivering chilled saline. [1][2][3][4][5][6][7] If induction of therapeutic hypothermia using chilled saline is to become a standard practice, then identifying a practical technique that will allow fluid to be infused closest to its initial refrigerator temperature is important. Therefore, the efficiency of infusion techniques should be measured and tested. The objective of this study was to assess the change in temperature of chilled saline upon exiting an infusion set in the laboratory setting while varying certain conditions. It was hypothesized that fluid temperature exiting an infusion set would vary dependent on insulation of the saline bag and infusion set.

Optimization of induction of mild therapeutic hypothermia with cold saline infusion: A laboratory experiment

“…In addition, insulated venous tubing sets and high flow rates (at least 100 mL/minute) shall be employed to avoid an excessive rise in fluid temperature from bag to the cannula. Our results performed using simple aluminum foil are in line with results published by other authors using dedicated insulation sleeves [7][8][9].…”

Effect of prehospital initiation of therapeutic hypothermia in adults with cardiac arrest on time-to-target temperature

“…Previous research suggests that the delay this protocol resulted in may not have any bearing on survival outcomes. 18,19 It is clear that early initiation of cooling is not the sole factor in achieving goal temperature and possible that delays arising from patient sedation, paralysis, deviation from hospital protocol, and additional TH induction measures impacted our results. Our centre's post-cardiac arrest clinical pathway is composed of a bundle of therapeutic interventions in addition to TH.…”

“…10,23 Adjustment for admission body temperature appears to negate the signal arising from analyses of this issue. 18,20 Garrett and colleagues suggested potential improved ROSC rates when intra-arrest cooling was used. 23 Taken in its entirety, the body of literature regarding the optimal timing of TH induction remains unclear.…”

Utilization of rapid infusion system with cold saline in the induction of therapeutic hypothermia

“…There are several techniques to improve the cooling effect of cold saline, including use of a pressure bag and insulating the cold saline bag and infusion set. 9,10 Table 1. Duration of infusion and initial and final saline temperatures in a laboratory-based experiment to determine the effectiveness of a rapid infusion system in the induction of therapeutic hypothermia using cold saline.…”

“…Insulation has been applied to minimise increases in saline temperature. 9,10 We hypothesized that the infusion of cold saline using a rapid infusion system (RIS; as used in many emergency departments) might be effective for the induction of hypothermia and assist in maintaining low saline temperatures. In a laboratory setting, RIS was compared with full dripping without other equipment (control) and the use of a pressure bag.…”