Intravenous Fluid Prescription Research Articles

Improving out-of-hours intravenous fluid prescribing for junior doctors: a prescription label.

Junior doctors are routinely asked to prescribe intravenous fluids (IVF) out-of-hours. Given time constraints and the number of unfamiliar patients, there is uncertainty about their prescription accuracy and safety, particularly in patients who have specific fluid balance requirements. An IVF prescription label was devised for the fluids section of the adult drug chart indicating important patient identifiers and diagnoses such as chronic heart/renal failure. The audit was carried out over a 16 day period, covering three weekends. A qualitative pre- and post-audit questionnaire assessed the confidence of junior doctors in out-of-hours IVF prescribing. All doctors based on the ward during that specific time period were targeted for the post-audit questionnaire. Post-audit, 58% (n=7) saw the label. 86% of those seven doctors stated the label had prompted them to do the following: a) examine the patient b) check blood results and c) urine output. 100% stated that the label improved their confidence in prescribing IVF. In addition, 71% felt the label made them more cautious in prescribing IVF and 43% felt they prescribed less. Overall, all seven (100%) doctors stated that the IVF prescription label was a useful addition to the drug chart. In conclusion, pressurised junior doctors would feel more confident prescribing IVF for unfamiliar patients if crucial information was readily visible on the drug chart. This would improve the accuracy of fluid prescribing and patient safety.

Intravenous fluid use in the acutely unwell adult medical inpatient: improving practice through a clinical audit process

Our Trust developed a clinical guideline to improve the prescribing and use of intravenous (IV) fluids based on the British consensus guidelines on IV fluid therapy for adult surgical patients. We audited the effect of targeted interventions to improve performance against this guideline. There were 53 IV fluid prescription charts in the pre-intervention audit and 48 in the post-intervention audit. Data was collected on the seven local practice standards ('local gold standards') in the clinical guideline; compliance with all of them was necessary to meet the IV fluid prescribing bundle of care. The proportion of prescriptions which met the IV fluid prescribing bundle of care increased (3.8% to 22.9% [p=0.004]) and the legibility of the IV fluid prescription increased (28.3% to 56.3% [p=0.004]). We have shown that the process of prescribing, administering and monitoring IV fluid use can be significantly improved through a range of targeted multi-disciplinary interventions.

An audit of perioperative fluid management and electrolyte monitoring in children undergoing surgery for scoliosis

To audite and compare the perioperative practices of intravenous fluids and electrolyte & glucose monitoring in children undergoing operations for scoliosis in 2008, 2010, prior to and after the publication of guideline in 2009. Retrospective audit was conducted at Peking Union Medical College Hospital, a tertiary referral teaching hospital in Beijing, China. Children under 14 years old with scoliosis treated surgically in 2008 and 2010 were recruited. The following data were collected from medical files: age, gender, weight, duration of hospitalization, concurrent illness, operation, anesthesia, fluid prescribed during perioperative fasting period, electrolyte monitoring and postoperative pain control, etc. Among 235 American Society of Anesthesiologists (ASA) I-II cases, 75 children received dextrose 5% or saline 0.9% during the preoperative fasting period. Intraoperatively, the anesthesiologists preferred dextrose 5% or saline 0.9% in children under 6 years old (n = 15, 2008; n = 15, 2010) and Ringer's solution in those aged 6 - 14 years (n = 84, 2008; n = 94, 2010) and hypotonic fluid was not used. And 82.3% and 94.3% of them received electrolyte examinations preoperatively. The electrolyte results were unavailable postoperatively in 27/122 (in 2008) and 13/113 (in 2010) and serum electrolytes were not assessed before fluid treatment postoperatively. Electrolytes were monitored only once in 82.3% (in 2008) and 70.5% (in 2010) patients. Compared with the preoperative concentration of sodium ion, the mean decrease was approximately 2.0 mmol/L at Day 1 postoperation. Hyponatremia at Day 1 postoperation in 2010 was more common than that in 2008 (26.2% vs 23.6%; P = 0.044). But no significant difference existed between the incidence of hyperglycemia of the same day in 2008 and that in 2010 (P = 0.306). Compared with that in 2008, our recent practice of intravenous fluid prescription and electrolyte monitoring is ill-consistent with the recommendations in 2009. Implementation of optimal perioperative fluid management is warranted.

Survey of paediatric intravenous fluid prescription: Are we safe in what we know and what we do?

The administration of i.v. fluids to children is common in hospital. There are risks associated with fluid therapy, especially iatrogenic hyponatraemia. The objective of this study was to assess the workplace practices and knowledge of tertiary hospital doctors regarding paediatric i.v. fluid prescription. This is a prospective, questionnaire-based observational study conducted at a 570-bed teaching hospital in June 2009. A convenience sample of doctors (n= 150), representing all levels of experience and all specialties that regularly prescribe paediatric i.v. fluids, were invited to participate. The main outcome measures consisted of demographical data and the ability to correctly prescribe paediatric fluids measured as 'fluid calculation', 'fluid choice' and 'total' percentage scores based on a percentage score of correctly answered questions using eight clinical scenarios. One hundred and six (71%) doctors returned a completed questionnaire. The great majority of respondents had a method for calculating a fluid bolus and maintenance rates (91% and 97%, respectively). Scenarios involving infants, especially where an increased risk of antidiuretic hormone secretion was possible, were answered poorly. Senior doctors performed better than junior doctors. ED and paediatric doctors performed better than those in other specialities. Most doctors in this Australian tertiary hospital have a correct method for prescribing bolus and maintenance fluid rates. However, the potential for adverse events from i.v. fluid prescription remains. Further education in this area for junior doctors, introduction of standardized guidelines for fluid use and restriction of available fluid choice may reduce the risk of iatrogenic hyponatraemia in children.

Multidisciplinary Education Improves Prescription of Balanced Crystalloids: A Pilot Study

To assess the use of balanced and unbalanced crystalloids in adult surgical patients. Prospective study of 65 adult emergency general surgical admissions in a UK acute district general hospital, with a further 45 patients studied following educational interventions. 36.4% of patients studied were prescribed inappropriate saline for resuscitation/replacement before the intervention. This compared with no inappropriate prescriptions (0%) after educational intervention (p = 0.0137). Simple multidisciplinary educational interventions can improve intravenous fluid prescription.

Intravenous fluids and hyponatraemia—a hospital based retrospective cross-sectional study: comparing with the national patient safety agency guidelines

<h3>Aim</h3> To audit prescribing of intravenous fluids and monitoring of electrolytes against the National Patient Safety Agency (NPSA) guidelines and investigate the relationship between type of intravenous fluids and incidence of hyponatraemia. Administration of hypotonic intravenous fluids is a common practice in hospitalised children and can result in dangerous hyponatraemia (plasma sodium, P_Na &lt;130); commonest associations are sepsis, gastroenteritis and postsurgery. Children are known to be more susceptible to complications of hyponatraemic encephalopathy. NPSA recommends use of 0.9% NaCl if P_Na ≤135 mmol/l. <h3>Methodology</h3> Data were collected from all patients admitted with hyponatraemia between September 2007 and July 2009; their demography, underlying diagnosis, comorbidity, type of fluid prescribed initially and later and repeat blood results were analysed. The data were analysed using SPSS software (version 17.0) and manually using Excel spreadsheet. <h3>Results</h3> There were 78 case entries with hyponatraemia (P_Na &lt;135) during our study period. The mean age was 5.9 years (range 0.1–16.0). Bloods were repeated in 45% of total patients950% of Group 1 (P_Na ≤130), 46% of Group 2 (P_Na 131–133) and 42% of Group 3 (P_Na &gt;133). The numbers of times electrolytes were measured varied, with mean of 1.58, median 2.0 (range 0–4). Intravenous fluids were prescribed in 81% of Group 1, 51% of Group 2 and 70% of Group 3. 12.5% received 0.9% NaCl as maintenance fluids, of them 44% were Group 1. Among Group 1 36% received 0.9% Saline, 45% received 0.45% saline and 19% had oral fluids. While acute pneumonia and sepsis constituted 54% of Group 1 and 20% of total, gastroenteritis was 21% and postoperative patients 9% of the total. 45% of Group 1 and 29% of Group 3 had a comorbid condition. <h3>Conclusion</h3> The practice of intravenous fluid prescribing for maintenance and ongoing losses, coupled with monitoring of serum electrolytes during the study period did not meet the recommended standards of NPSA guidance published in March 2007. New guidelines have now been in effect since July 2009. We recommend a prospective audit with strict adherence to the guidelines to avoid possible disastrous consequences and ensure uniformity of practice.

Don't forget potassium!

Dear Editor, I read with great interest the article entitled “The impact of the National Patient Safety Agency intravenous fluid alert on iatrogenic hyponatraemia in children” by Drysdale et al. published in this journal [2]; we would like to draw attention regarding the serum potassium level. In March 2007, the National Patient Safety Agency (NPSA) issued an alert regarding intravenous fluid (IVF) prescription to hospitalized infants and children (NPSA alert 22). Drysdale et al. supported the alert by demonstrating that the solution recommended by NPSA (0.45% or 0.9% saline/ 5% dextrose) as maintenance IVF reduced the risk of iatrogenic hyponatremia. Though I agree in general that hypotonic solution such as 0.18% saline/4% dextrose should be replaced by isotonic solution, I am worried about development of iatrogenic hypokalemia which the authors did not mention in the article. According to the historical article by Holliday and Segar regarding the maintenance need for calories, water, and electrolytes in parenteral fluid therapy for children, daily intake of potassium is recommended to be 2.0 mEq/100 cal [3]. Therefore, some pediatricians including me prefer to add potassium into the maintenance fluid whatever that is hypotonic or isotonic [4], though others do not [1, 2]. Armon et al. reported that 23% of children receiving IVF were hyopokalemic, of whom, 24% were not receiving potassium in their IVF [1]. Therefore, I recommend that potassium should be added into the isotonic solution for maintenance fluid replacement therapy in children.

The impact of the National Patient Safety Agency intravenous fluid alert on iatrogenic hyponatraemia in children

In March 2007, the National Patient Safety Agency (NPSA) issued an alert regarding intravenous fluid (IVF) prescription to hospitalised infants and children, to be implemented in UK hospitals by September 2007. Previously, the most commonly used IVF (0.18% saline/4% dextrose) has been associated with iatrogenic hyponatraemia, resulting in four deaths and one near miss since 2000. The alert recommended 0.45% (or 0.9%) saline/5% dextrose as maintenance IVF and banned 0.18% saline/4% dextrose. We audited practice and outcome in children receiving maintenance IVF in June 2007 (before guideline implementation) and June 2008 (after guideline implementation). In June 2007, 44 (30%) children were prescribed IVF, six received IVF not recommended by NPSA alert 22 and one became hyponatraemic. In June 2008, 56 (30%) children received IVF; one received IVF not recommended by NPSA alert 22 and became hyponatraemic. The median change in serum sodium levels for all children who received IVF not recommended by NPSA alert 22 [-5 (-15 to 0) mmol/l] was significantly greater than those who received IVF recommended by NPSA alert 22 [0 (-13 to +7) mmol/l, p = 0.002]. In addition, there was a significant (p = 0.04) reduction in the number of children who had electrolytes checked while on IVF after implementation of the guideline. Implementation of a new IVF guideline has been associated with less use of IVF not recommended by NPSA alert 22, resulting in less serum sodium level reduction. The only children who became hyponatraemic received IVF not recommended by NPSA alert 22. Despite the NPSA alert and guideline implementation, less children had electrolyte levels checked while receiving IVF.

The impact of an interactive teaching session on the administration of potassium in patients having surgical repair of a fractured neck of femur

Over 80 000 patients per year undergo surgery for the repair of a fractured hip. This is associated with 30-day mortality of around 10% [1]. Fluid administration is an important aspect of the peri-operative management of these elderly patients, who often have multiple medical co-morbidities. A previous audit at our institution showed a high incidence of hypokalaemia at the time of surgery that had been associated with tachyarrhythmias and operative delay. One causative factor was the inadequate pre-operative prescription of potassium-containing intravenous fluids, despite the provision of written guidelines. All new orthopaedic junior doctors attended a tutorial as part of their induction process. This was a problem-based learning session focusing upon fluid prescribing in the pre-operative period and lasted for 20 min. Three key learning points were emphasised: (i) potassium requirements are 0.5–1.0 mmol.kg−1.day−1; (ii) urea and electrolytes should be measured daily in patients having intravenous fluids; and (iii) aim for a serum potassium level of 4.0–4.5 mmol.l−1. Potassium administration for every inpatient who had a fractured neck of femur surgically repaired was audited by a snapshot data collection before and after the institution of the teaching tutorial. Fisher’s exact test was used for statistical analysis. Changes in potassium prescribing are shown in Table 1. We have shown that a short teaching session can improve a key aspect of peri-operative care. Junior medical staff are responsible for 89% of fluid prescribing, but due to inadequate knowledge, suboptimal prescribing is common [2]. Focussed teaching on clinically relevant topics appears to be superior to the provision of guidelines alone and may be of value as part of the induction of junior doctors.

Impact of NPSA guidelines on intravenous fluid prescription in children - A retrospective audit on fluid prescription in children undergoing appendicectomy

Objectives: To determine if intravenous (IV) fluid and electrolyte monitoring practice has changed in our children's hospital since the introduction of guidelines by the National Patient Safety Agency. Introduction: In March 2007, the National Patient Safety Agency (NPSA) published guidelines for clinicians involved in IV fluid prescribing to reduce the risk of hyponatraemia and harm to children. Key recommendations were to use 0.9% sodium chloride (NaCl) for resuscitation boluses; isotonic maintenance IV fluids should be prescribed to those at risk of hyponatraemia; plasma electrolytes should be measured prior to commencing fluids and at least daily subsequently; fluid balance and weight should be accurately recorded; gastro-intestinal losses should be replaced with NaCl 0.9%. A retrospective audit of IV fluid management in appendectomy patients admitted prior to the NPSA publication was previously completed in our tertiary referral children's hospital (audit1) [2], showing significant discrepancies in clinical practices when compared to the new guidelines. A second retrospective audit has now been completed in our hospital to determine if practices have subsequently changed since the dispersal and implementation of the guidelines. Method: We reviewed 50 consecutive notes available in the medical records department of children who had undergone appendectomy between October 2007 and October 2008. We used a structured questionnaire (identical to that used in audit 1) [2] to review three time periods: the preoperative period; intraoperative period and the postoperative period. We recorded the fluid types and volumes given as resuscitation boluses, maintenance fluids and nasogastric loss replacement; the frequency and timing of plasma electrolyte measurements; the relationship, if any, between plasma sodium [Na] concentration and the IV fluid prescribed and biochemical monitoring; and when the patient had been weighed. We then compared the results to those found in audit 1 [2], to see if there were any changes in the practice of intravenous fluid prescription. Results: A total of 49 patients had acute appendicitis; one underwent interval appendectomy. The median age was 9.5 years (range 2–13 years). ·Plasma electrolyteswere measured in 98% of patients on admission prior to commencing IV fluids (c.f. 97% in audit 1) [2]. Plasma[Na] was 135mmol l-1 initially on admission subsequently developed hyponatraemia (c.f. 6% in audit 1) [2]. ·Plasma electrolyteswere measured daily in only 14% patients receiving IV fluids (similar to audit 1) [2]. ·Fluid boluses were isotonic on all occasions and all were accurately calculated according to weight, (520mls kg-1) (similar to audit 1) [2]. ·Maintenance fluidsbefore surgery were hypotonic in 78% patients. During surgery, 10% of patients received hypotonic maintenance fluid (c.f. 29% in audit 1) rather than the recommended isotonic fluid. After surgery, 56% of patients received solely hypotonic fluids (84% in audit 1) [2]. All maintenance fluids were appropriately calculated according to weight using the Holiday and Segar formula [3]. Hypotonic maintenance fluids were continued in 8/14 (57%) patients with documented hyponatraemia (88% in audit 1) [2]. ·Nasogastric losseswere replaced with NaCl 0.9% in the three patients in which these were significant. · All patients were weighedon admission but none subsequently. Conclusions: Practice has changed since the implementation of the NPSA guidelines, but there still discrepancies in management, particularly the frequency of electrolyte monitoring, fluid choice in children with documented hyponatraemia and additionally choice of postoperative maintenance fluid. There is still a need for improvement in perioperative fluid management in children to comply with the NPSA standards.

Fluid optimisation using a peripherally inserted central catheter (PICC) following proximal femoral fracture: Lessons learnt from a feasibility study

Summary The aim of this study was to test the feasibility of using peripherally inserted central catheters (PICCs) in older people to enable fluid optimisation. Fourteen patients were randomised to three groups: (i) usual care, insertion of short peripheral intravenous cannulae and normal fluid prescription; (ii) PICC insertion and normal fluid prescription; (iii) PICC insertion and guided fluid prescription based on measurements of central venous pressure (CVP). A range of outcome measures were undertaken, plus two focus groups with ward staff and an interview with the research nurse to ascertain views concerning the implementation of the study. Descriptive findings identified that PICC use in this group of patients was extremely difficult. The practical issues affecting the feasibility of this study were: (i) the physical and psychological frailty of the patients, proxy consent, difficulties measuring outcomes, unsuccessful PICC placement due to aged veins, intolerance to lines; (ii) staff concerns relating to patient vulnerability, competent use of new technology, limited resources and work capacity. Most aspects of the trial were made more difficult due to the frailty of the patient group.

Intravenous cannulation, intravenous infusion and prescription of intravenous fluids

Intravenous cannulation, intravenous infusion and prescription of intravenous fluids

An audit of intravenous fluid prescribing and plasma electrolyte monitoring; a comparison with guidelines from the National Patient Safety Agency

To audit past practice of intravenous (i.v.) fluid prescribing and electrolyte monitoring, prior to the publication of guidelines by the National Patient Safety Agency (NPSA, Ref. NPSA/2007/22) in March 2007, highlighting areas of discrepancy, in a specialist children's hospital. We performed a retrospective case note review of 100 appendectomy patients between February 2004 and March 2007, recording; fluid type and volumes given as maintenance therapy, resuscitation boluses and nasogastric replacement; the frequency and timing of plasma electrolyte measurement; the relationship between plasma sodium [Na] concentration and i.v. fluid prescribed; and patient weight recordings. Ninety-eight acute appendectomies and two interval elective appendectomies. Median age 10 years (interquartile range: 8-11.25). Before surgery, hypotonic maintenance fluid was prescribed for 94% patients. During surgery, maintenance fluid was predominantly isotonic. After surgery, hypotonic maintenance fluid was prescribed for 92% patients. All maintenance fluid volumes were appropriately calculated according to weight using the Holliday and Segar formula (Paediatrics, 19, 1957, 823). Fluid boluses were isotonic on 128/129 occasions and all accurately calculated according to weight. Nasogastric losses were replaced with 0.9% sodium chloride. No patient had daily plasma electrolyte measurements whilst administered i.v. fluid. Twenty-seven patients had recorded hyponatremia ([Na] <135 mmol x l(-1); 21 at presentation, six subsequently after admission). Hypotonic maintenance fluid was continued in 26/27 patients with hyponatremia. No patient had daily weight recorded. Our practice of i.v. fluid prescribing and electrolyte monitoring in children, prior to the publication of guidelines by the NPSA in March 2007, did not fully meet the recommended standards.

Iatrogenic hyponatremia in hospitalized children: Can it be avoided?

Iatrogenic hyponatremia in hospitalized children is a common problem. It is usually caused by the administration of free water, either orally or through the prescription of hypotonic intravenous fluids. It can result in cerebral edema and death, and is most commonly reported in healthy children undergoing minor surgery. The current teachings and practical guidelines for maintenance fluid infusions are based on caloric expenditure data in healthy children that were derived and published more than 50 years ago. A re-evaluation of these data and more recent recognition that hospitalized children are vulnerable to hyponatremia, with its resulting morbidity and mortality rates, suggest that changes in paediatricians' approach to fluid administration are necessary. There is no single fluid therapy that is optimal for all hospitalized children. A thorough assessment of the type of fluid, volume of fluid and electrolyte requirements based on individual patient requirements, plus rigorous monitoring, is required in any child receiving intravenous fluids. The present article reviews how hyponatremia occurs and makes recommendations for minimizing the risk of iatrogenic hyponatremia.

Intravenous postoperative fluid prescriptions for children: A survey of practice

BackgroundPostoperative deaths and neurological injury have resulted from hyponatraemia associated with the use of hypotonic saline solutions following surgery. We aimed to determine the rates and types of intravenous fluids being prescribed postoperatively for children in the UK.MethodsA questionnaire was sent to members of the British Association of Paediatric Surgeons (BAPS) and Association of Paediatric Anaesthetists of Great Britain and Ireland (APAGBI) based at UK paediatric centres. Respondents were asked to prescribe postoperative fluids for scenarios involving children of different ages. The study period was between May 2006 and November 2006.ResultsThe most frequently used solution was sodium chloride 0.45% with glucose 5% although one quarter of respondents still used sodium chloride 0.18% with glucose 4%. Isotonic fluids were used by 41% of anaesthetists and 9.8% of surgeons for the older child, but fewer for infants. Standard maintenance rates or greater were prescribed by over 80% of respondents.ConclusionMost doctors said they would prescribe hypotonic fluids at volumes equal to or greater than traditional maintenance rates at the time of the survey. A survey to describe practice since publication of National Patient Safety Agency (NPSA) recommendations is required.

Patterns and Clinical Outcomes Associated with Routine Intravenous Sodium and Fluid Administration after Colorectal Resection

Excess intravenous water and sodium may be associated with postoperative complications and an adverse outcome. However, the effect of the magnitude of the surgery on such a relation has not been studied. This study assesses current practice in intravenous fluid and sodium administration after colonic and rectal resection and its relation to the postoperative outcome. A series of 100 consecutive patients undergoing elective colonic (n = 44) or rectal resection (n = 56) were included in a retrospective case-cohort study. The volumes of water and sodium from intravenous fluid and antibiotic administration on the day of surgery and the next 5 days were recorded together with the clinical outcome. The mean +/- SEM fluid and sodium administration on the day of operation was greater after rectal than colonic resection (4.6 +/- 0.2 vs. 3.6 +/- 0.2 liters and 507 +/- 34 vs. 389 +/- 22 mmol, respectively (p < 0.05). The mean +/- SEM rate of daily fluid and sodium administration for the 5 subsequent days was greater following rectal than colonic resection (2.1 +/- 0.1 vs. 1.8 +/- 0.1 L/day and 155 +/- 8.7 vs. 128 +/- 8.0 mmol/day; p < 0.05). For all resections, there were no differences in fluid and sodium administration on the day of surgery in patients with or without postoperative complications. During the subsequent 5 days, patients with complications after colonic resection had a higher postoperative mean rate of intravenous sodium administration than those who did not (149 +/- 12 vs. 115 +/- 10 mmol; p < 0.05). A similar pattern was not observed following rectal resection. Current postoperative intravenous fluid prescription delivers approximately 2 liters of fluid and 140 mmol of sodium per day. Complications after colonic, but not rectal, resection are associated with more early postoperative daily intravenous sodium administration. Because colonic resection poses less of a physiologic insult than rectal resection, the overall outcome in the former group may be more sensitive to the interplay between fluid and sodium overload and patient co-morbidity.

Clinical Practice 02

Aims: Over 50 per cent of adverse events suffered by hospital patients in the United Kingdom occur in general ward care, including the prescription of medications and intravenous fluids (IVF). We performed a prospective evaluation of IVF prescription for postoperative patients in a surgical unit. Methods: Data were prospectively collected regarding fluid balance, electrolyte status, fluid prescription and adverse events for each postoperative day until IVF were discontinued. The first 24 h were excluded. Patients receiving parenteral nutrition were excluded. Results: Thirty-nine postoperative patients representing 103 patient days were included. Total daily volume of fluid prescribed [median (interquartile range)] was 3000 mL (1000 mL) in elective patients and 2500 mL (1000 mL) in emergency patients. There was no correlation between daily volume prescribed and patient weight (correlation coefficient: −0.104; P = 0.373). Correlation between electrolyte prescriptions and serum electrolytes was also poor. There was an inverse correlation between total volume prescribed and total losses in the previous 24 h (correlation coefficient: −0.2; P = 0.044). Seven patients required fluid challenges for hypovolaemia after the first postoperative day, three developed fast atrial fibrillation and one developed congestive cardiac failure requiring transfer to a critical care area after receiving 4 L of crystalloid in the previous 24-h period. There were no perioperative deaths. Conclusions: Fluid prescription is highly variable. It is not tailored to the individual patient and may lead to adverse events. The use of precalculated fluid regimens based on the patients' body mass index with additions for ongoing losses may improve current practice.

VARIABILITY IN POST‐OPERATIVE FLUID AND ELECTROLYTE PRESCRIPTION

SUMMARY A four‐week retrospective survey of intravenous fluid and electrolyte prescriptions on postoperative surgical patients revealed wide variability in fluid and electrolyte prescription by medical staff. Median volume of intravenous fluid prescribed was 3000 ml (range 1667‐5000). Total sodium prescribed varied from 0 to 770, median 242 mmol/day), with potassium infrequently added (range 0‐81, median 0 mmol/day). Patients undergoing emergency surgery were prescribed more sodium than those undergoing routine procedures (p=0.0403); 0.9% saline was the most common fluid prescribed overall. There was poor correlation between serum electrolyte values and the amounts of electrolytes prescribed. Intravenous fluid prescription should take into account the post‐operative stress response which reduces sodium requirements (unless there are other concomitant losses) and increases urinary potassium losses. A suitable post‐operative ‘maintenance’ fluid is 4% dextrose/0.18% saline with 1‐2 g potassium chloride, particularly if serum electrolyte levels are not known. Other fluid losses should be replaced with equivalent fluids.