Postoperative fluid management

 


Oesophageal cases

  1. In general oesophageal cases lose a lot of fluid during surgery and in the first few days postop. This is exacerbated by epidural anaesthesia and postoperative ventilation. They frequently need substantial fluid replacement.

  2. Nil by mouth till informed otherwise by Consultant.

  3. Two litres of Dextrose 4%, 0.18% N.Saline (No. 18 Soln) over first 24 hours (80cc/hr) as baseline. No added potassium unless K less than 4.0.

  4. Further boluses as Colloid (Gelofusion, HPPF, Blood as indicated clinically) during rewarming phase and to replace losses in drains etc.

  5. Thereafter Dextrose 4%, 0.18% N.Saline (No. 18 Soln) with 20 meq KCl per 500 cc bag, 2.5 - 3.5 litres per day depending on weight of patient.

  6. Decrease appropriately as oral fluids tolerated.

  7. Hiatal hernia repairs may be able to start sips of water the day following surgery if nausea is not a problem.

  8. Oesophagectomies should not have oral intake till cleared with consultant (usually after Niopam swallow on day 5-7 for Mr McGuigan's patients)


Pulmonary cases

In the post-pulmonary resection patient, particularly postpneumonectomy, fluid management is crucial and akin to a high wire act.

All patients with epidurals should have urinary catheters. All elderly males, especially those undergoing pneumonectomy should also have urinary catheters to assist in monitoring of urine output.

In general lung resection patients do not require the same amounts of postoperative fluids as general surgical patients and certainly not as much as oesophagectomies. Excess fluid, particularly in pneumonectomy patients can cause "downside" post pneumonectomy pulmonary oedema which is almost invariably fatal in this situation. This is exacerbated by postoperative overhydration, lymphoedema after extensive subcarinal node dissections and intrapulmonary barotrauma due to rapid over-expansion of the residual lung. The danger period for this is 24-36 hours. It may be difficult to differentiate from sputum retention and pneumonia.

Over the subsequent days, however, there is a substantial serous fluid loss into the pneumonectomy space and excessive fluid restriction may produce a relative dehydration and even renal failure. It may also cause thickening of bronchial secretionsleading ultimately to pneumonia.

Intraoperative fluids

  1. The anaesthetist will decide on appropriate intra-operative fluid restriction. e.g. restrict to 1200 cc (except in cases of severe blood loss).


Postoperative fluids

  1. Intravenous - 1 litre of Dextrose 4%, 0.18% N.Saline (No. 18 Soln) over first 24 hours (40cc/hr) as baseline. Adjust this downwards if intraoperative fluids were high. No added potassium unless K less than 4.0. Take down IV the morning after surgery if fluids are being tolerated orally. Patients recover fluid balance despite our intravenous fluids and diuretics rather than because of them. In a patient with an intact alimentary canal the safest route for fluids is oral.

  2. On the day of surgery clear fluids may be commenced once the patient is fully awake, able to talk and able to coordinate swallowing. (If hoarseness suggests a recurrent laryngeal nerve palsy hold oral intake).

  3. If tolerating clear fluids postop, may commence soft diet the day following surgery. Diet may be advanced as tolerated thereafter.

  4. Restrict total fluids to 1500cc per day (up to 2000cc for larger patients) for the first two post-operative days.


Blood transfusions

  1. If there is active blood loss which is haemodynamically significant it should be replaced with blood

  2. Excessive serous loss should be replaced with colloid.

  3. We have no didactic rules regarding the Hb level at which we transfuse patients postoperatively. General surgical and anaesthetic myths about a Hb of 10 do not apply on the Thoracic unit.

  4. Remember that blood is one of the most dangerous drugs we use and think carefully whether it is really required.

  5. There are some suggestions that transfused blood is immuno-suppressive and therefore more likely to allow metastatic spread of tumour.

  6. Patients who have had chemotherapy will not have the usual numbers of red cells sequestered in their bone marrow and will not respond normally to operative blood loss. Therefore have a lower threshold for transfusing such patients.

  7. Similarly patients admitted for palliation may benefit from transfusion at level higher than other patients.


See: "Poor urinary output" after lung resection