Preoperative measures

Preoperative treatment in the patient with generalised peritonitis is as important as surgery:

• correct fluid balance due to lost extracellular fluid:
  • give a rapid IV infusion of Hartmann's solution, 2.5-3.0 litres over 3 hours in a 70kg adult
  • monitor central venous pressure in elderly patients to ensure that infusion is not given too quickly
  • insert a urinary catheter to monitor urinary output
  • give additional colloid if there is evidence of hypovolaemia
• remove blood for culture, then give parenteral antibacterial treatment, e.g. metronidazole for anaerobes and cephalexin for aerobes
• give analgesic, preferably IV slowly, after consulting with the anaesthetist
• give oxygen via a face mask as diaphragmatic movements are likely to be reduced
• before inducing anaesthesia, pass a 16F nasogastric tube to keep the stomach empty