The perioperative fluid has always been the topic of debate. This fluid aims to restore the blood during the immediate perioperative period. Maintaining effective blood pressure and blood volume are two key components of adequate organ perfusion while avoiding the risk of organ hyper or hypo fusion.
Intravenous fluid therapy is important for critically ill patients and those undergoing surgery. Fluid therapy and vasoactive drugs are used to maintain the body fluid during the surgery. This fluid therapy aims to maximize stroke volume and hypovolaemia. However, this fluid overload can cause harm in all types of surgery.
IV fluid administration aims to restore and maintain tissue fluid and electrolyte homeostasis and central euvolemia while avoiding salt and water excess. This will in turn facilitate tissue oxygen delivery without causing harm. Achieving optimal IV fluid therapy should improve perioperative outcomes and is a key component in many perioperative guidelines and pathways.
MedPiper Technologies and JournoMed in association with ISA Thrissur City Branch conducted a webinar titled “Perioperative Fluid: How Much is Not Too Much?” that explores everything about perioperative fluid and its roles in surgery.
Expert Speaker: Dr. SHALINI SAKSENA, Director of Onco-Anaesthesia and Onco Pain Management at Nanavati Max Institute of Cancer Care, Nanavati Max Super-Speciality Hospital, Mumbai.
Fluid Theory-What has changed?
- Resuscitation- If the patients require IV fluid resuscitation, then the one with sodium ranging from (130-to 154) mmole/l with a bolus of 500 ml over less than 15 minutes should be used
- Routine Maintenance- If the patient needs IV fluid for routine maintenance, then restrict the initial prescription to 25-30 ml/kg/day of water, approximately 1 mmol/kg/day of potassium, sodium, and chloride, and 50–100 g/day of glucose to limit starvation ketosis
Third Space – Is it there or not?
For decades, the ‘third space’ was looked upon as an actively consuming compartment. Therefore, perioperative fluid regimens were traditionally based on a generous replacement of this assumed primary loss, in addition to deficits due to insensible perspiration and fasting. The practical consequence was an extremely positive fluid balance to maintain blood volume during major surgery. Whereas the insensible perspiration and the preoperative deficits are often negligible, and the third space appears to be only a fictional construct, the excess fluid most likely accumulates interstitially.
Perioperative Fluid Administration
The intravenous “drip” was introduced by Rudolph Matas in 1924. Intravenous fluids (IVF) first gained therapeutic importance in the treatment of cholera in the 1830s. From the 1880s, IVF began to be administered perioperatively to compensate for the “injurious” effects of anesthesia. Clinical improvements were consequently noted, though the adverse effects of saline were observed. The work of Ringer, Hartmann, and others emphasized the importance of the composition of IVF and laid the foundations for the balanced solutions in use today.
Pulmonary edema is a common disorder of the lung. It is due to an increase in pulmonary vascular permeability that can reflect increased transpulmonary hydrostatic pressure due to elevated pulmonary venous pressure, changes in pulmonary vascular permeability, endothelial injury, and decreased oncotic pressure.
These factors are determined by the Starling equation, Q = k(Pcap − Pint) − σ(pcap − pint), in which the movement of edema fluid into the lung depends on the hydrostatic and oncotic pressure differences between the pulmonary capillary and the lung interstitium.
Why do we give so much fluid?
Water, sugar, and salt are important in helping the body to function. Intravenous fluids (usually shortened to ‘IV’ fluids) are liquids given to replace water, sugar, and salt that you might need if you are ill or having an operation, and can’t eat or drink as you would normally. IV fluids are given straight into a vein through a drip.
The most common practice area of responsibility for anesthesiologists is preoperative IV fluid therapy. It’s a major challenge during surgery. Individualized volume optimization using goal-directed therapy is warranted during high-risk surgery. In most patients, balanced crystalloids are the first choice of fluids to be used in the operating theatre.
Additional research on the optimal type of fluid for use during major surgery is needed. Optimizing perioperative fluid management is a key objective during major surgery. A zero-fluid balance goal, with the maintenance of preoperative body weight, should be aimed for. Goal-directed therapy is warranted during high-risk surgery.