The prescription of fluids after the surgery is routine in the operation and anesthesia departments and does not usually constitute any research problems. In this context, no studies on possible alternatives to fluid therapy are performed. For this reason, a primary conceptual problem is that ideas and current practice of post-operative fluid therapy are usually based on non-systemic clinical experience and individual case report without the existence of extensive comparative studies.
In this regard, some authors point out in recent years, and with greater emphasis in recent review articles 1, the relevance of the composition of electrolyte fluids during the surgery and in the first few days after. Against this background, the complete substitution of isotonic solutions has been suggested in all operations where an unusually high loss of free water is not calculated.1 The reason for this proposal is to avoid cases of severe hyponatremia, the important and even fatal consequences broadly documented. , especially among the pediatric population and menstruating women. other authors, however, claimed that the fluids were most commonly used, as traditionally 50% isotonic saline and are (0.9%, [Na +] 155 mmol / L) of free water than 5% dextrose, not even a risk factor darstellen.2 This This statement should take into account the exception of selected patients who have other comorbid conditions and may need a particular fluid composition.
It is important to note that there is no evidence available because work on the subject has not been published, demonstrating the potential consequences of a generalized use of isotonic saline throughout the postoperative population, although some authors have highlighted the potential risks by administering excess fluids and salt in the postoperative period.3, 4
When searching for Medline we have found either in Spain or abroad, a single study that is largely enough and systematically records the type of fluid and electrolyte replacement in surgical departments during the immediate post-operative period and its impact on the internal environment . In addition, we have not found any evidence-based recommendation supported by comparative data with different fluid therapies. In the case of UK reports, a combination commonly used for parenteral fluid replacement, 0.18% NaCl in 4% Dextrose.5, 6 in another study, nearly 50% of patients received 5% dextrose in water for the postoperative treatment. 7
Based on these premises, we found it necessary and useful to prospectively evaluate this problem in a normal postoperative population. For this purpose we created a database our group analyzing water and electrolyte handling outside of complicated postoperative patients considering three specific aspects: 1) the amount and composition of the administered fluids; 2) the possible deficiencies in the hydro salt solution between treatment start and the first 24 hours after surgery and 3) the presence or absence of clinical changes, possibly due to serum sodium variations.
PATIENTS AND METHODS
We prospectively examined 120 patients who undergo elective surgery under general anesthesia and performed at a university hospital.
We have used the following exclusion criteria: 1. Initial surgery: Extremely complicated operations, including cardiac surgery with extracorporeal circulation, radical oncology surgery, extensive intestinal surgery, high comorbidity, especially cardiac, respiratory or renal failure (SCR> 1.3 mg / dl) and insulin-dependent diabetes mellitus; Medicine with cardiovascular and renal effects with a possible influence on the hyponatremia, mainly diuretics. 2. Intra- and postoperative fever, bleeding, myocardial ischemia, painful conditions, severe vomiting and need for re-operation.
In order to obtain meaningful data reflecting daily practice, we have not made any changes to routine practices of surgeons and anesthetists. Data collection was performed by clinical researchers who were not in surgical wards. The study was approved by the institution’s ethics committee. In all cases and in accordance with international and internal rules, we have written consent from the patients to collect data and