Laparoscopic Appendectomy

Laparoscopic cases (general considerations): The patient's peritoneum is insufflated (which is called a pneumoperitoneum), and instrumentation will be inserted into the abdomen. General anesthesia, ETT tube, and paralytics are necessary. Some of the procedures are rather short, so make sure the timing is right to reverse the paralytic. The pressure in peritoneum affects the organs of that space. Anything more than 10 mmHg will begin to alter hemodynamics. Cardiac output is decreased and SVR is increased. Renal vessels will be compressed, which reduces flow to the kidneys, and activates the renin angiotensin aldosterone system (RAAS). Reduced blood to the kidney means reduced urine output. Peak inspiratory and plateau pressures will also increase. The gas used to insufflate the peritoneum is CO2 – so, as you might guess, hypercarbia can develop – and with it, acidosis. You'll see this sometimes reflected in the end-tidal CO2. This is all adding to the stress response we try to avoid in anesthesia.

Trendelenburg Position (general considerations): Take precautions for upper airway obstruction or stridor. Avoid excessive fluid administration. OG tube is a good consideration to empty the contents of the stomach. Regurgitation of stomach contents can ulcerate the airway and/or damage the eyes. Consider throat packs and/or eye lubrication to further protect the patient. Brachial nerve injury is also a strong possibility. Be very careful with head and shoulder brace positioning. Peroneal nerve injury is a strong possibility if the patient is also in the lithotomy position. Make sure pressure points are padded. If there's peroneal nerve damage, it will manifest as foot drop. Increased IOP. Take precaution with patients that have glaucoma. Conjunctival swelling will sometimes be irritating to the patient post-operatively. Keep reminding the patient not to rub their eyes. Increased ICP. Cerebral perfusion pressure = MAP-ICP. Make sure you keep the MAP up.