Perioperative intravenous fluid prescribing: a multi-centre audit

Abstract

Background: Excessive or inadequate intravenous fluid given in the perioperative period can affect outcomes. A number of guidelines exist but these can conflict with the entrenched practice, evidence base and prescriber knowledge. We conducted a multi-centre audit of intraoperative and postoperative intravenous fluid therapy to investigate fluid administration practice and frequency of postoperative electrolyte disturbances.

Methods: A retrospective audit was done in five hospitals of adult patients undergoing elective major abdominal, gastrointestinal tract or orthopaedic surgery. The type, volume and quantity of fluid and electrolytes administered during surgery and in 3 days postoperatively was calculated, and electrolyte disturbances were studied using clinical records.

Results: Data from four hundred thirty-one patients in five hospitals covering 1157 intravenous fluid days were collected. Balanced crystalloid solutions were almost universally used in the operating theatre and were also the most common fluid administered postoperatively, followed by hypotonic dextrose-saline solutions and 0.9 % sodium chloride. For three common uncomplicated elective operations, the volume of fluid administered intraoperatively demonstrated considerable variability. Over half of the patients received no postoperative fluid on day 1, and even more were commenced on free oral fluids immediately postoperatively or on day 1. Postoperative quantities of sodium exceeded the recommended amounts for maintenance in half of the patients who continued to receive intravenous fluids. Potassium administration in those receiving intravenous fluids was almost universally inadequate. Hypokalaemia and hyponatraemia were the common findings.

Conclusions: We documented the current clinical practice and confirmed that early free oral fluids and cessation of any intravenous fluids is common postoperatively in keeping with the aims of enhanced recovery after surgery programmes. Excessive sodium and water and inadequate potassium in those given intravenous fluids postoperatively is common and needs to be investigated. The variation in intraoperative fluid volume administration for three common procedures is considerable and in keeping with other international studies. Future trials of fluid therapy should include the intraoperative and postoperative phases.

Keywords: Anaesthesia; Electrolytes; Intravenous fluids; Perioperative; Postoperative; Surgery.

Fig. 1

Flow chart demonstrating the target number of patients at each hospital and the number successfully included in the audit

Fig. 2

Type of intravenous fluid administered in different phases of the perioperative pathway. Balanced crystalloid solutions were the most common fluid administered at all stages of the perioperative pathway expressed as the percentage of the total volume of intravenous fluid used. Balanced crystalloids (Hartmann’s and Plasma-Lyte), hypotonic dextrose-saline solutions (0.18 and 0.45 % dextrose-saline), dextrose solutions (5 and 10 % dextrose) and HAS (human albumin solution)

Fig. 3

Type of intravenous fluid administered intraoperatively and on postoperative day 1. This graph illustrates the different types of balanced crystalloid that were used in this audit. It demonstrates that Hartmann’s is the dominant balanced crystalloid used in Wessex

Fig. 4

Type of fluid administered on postoperative day 1 in different clinical areas. The type of fluid administered on postoperative day 1 varied depending if the patient was cared for in a ward or ward-based HDU environment compared to an ICU environment. HDU high dependency unit, ICU intensive care unit

Fig. 5

Volume of intraoperative fluid administered for three common surgeries. Volume of fluid administered expressed as ml.kg⁻¹ during the entire operation. Error bars represent the interquartile range. The wide horizontal line represents the median. Abbreviations: THR total hip replacement, TKR total knee replacement

Fig. 6

Intravenous fluid received on postoperative days 1, 2 and 3. Percentage of all patients who received different volumes of intravenous fluid expressed as ml.kg.day⁻¹

Fig. 7

Volume of intravenous fluid given on postoperative day 1 compared to body weight. In those patients receiving intravenous fluid on postoperative day 1, there was no relationship between volume received and body weight

Fig. 8

Serum sodium on each perioperative day and type of fluid given on postoperative day 1. Mean values of serum sodium on each perioperative day grouped by the type of fluid (given in the largest volume) on postoperative day 1. Error bars represent the standard error of the mean (SEM). Hypotonic dextrose-saline solutions (0.18 and 0.45 % dextrose-saline) and dextrose solutions (5 and 10 % dextrose)