Most patients have little recall of “going under.” Those who do typically remember pleasant and relaxed feelings. Individuals who are sedated with propofol often report quite vivid dreams, which are typically pleasant in nature. Propofol-based sedation also causes complete or near-complete amnesia for the procedure, but memory and most cognitive functions typically return nearly to normal prior to discharge. Patients sedated with propofol rarely complain of feeling "drugged" and more often remark that they feel as if they had a great nap. While fentanyl and other opioid-type drugs may cause nausea, particularly at higher doses, this is rare with propofol.
There is considerable variation from patient to patient with respect to tolerance for these procedures. Some patients may be able to tolerate an unsedated upper endoscopy well but not colonoscopy, and vice versa.
The ability to tolerate an unsedated upper endoscopy depends largely on the sensitivity of your gag reflex and your general anxiety level about the procedure. If you are highly motivated to avoid sedation and can wiggle two of your fingers in the back of your throat for a few minutes without gagging or retching you may be a good candidate to try unsedated endoscopy. However, if even the thought of fingers in your throat makes you gag it is unlikely that you will tolerate the exam without sedation.
The ability to tolerate colonoscopy without sedation or with conventional moderate sedation depends on factors relating to your sensitivity to anal and rectal manipulation, manipulation of the colon and its supporting tissues, and to the amount of manipulation of the colon necessary to complete the exam, which is quite variable from patient to patient and difficult to predict before the procedure. In addition, the need for sedation in colonoscopy depends on the technical difficulty of the exam, which also is variable and hard to predict. In general, thin woman tend to be more difficult to examine than overweight men, though this is not universal. A prior hysterectomy also seems to predict a more difficult exam.
Propofol provides much more flexibility in meeting sedation needs than sedation with fentanyl-midazolam because of its very rapid onset, the range of sedation depth that can be safely achieved, and the short duration of effect. With propofol it is possible for your doctor to take you "deeper" for one to two minutes during what might otherwise be a painful insertion of the colonoscope through the left side of your colon (the part of the exam most often associated with discomfort) and then "lighten you up" for the remainder of the examination. If desired, propofol sedation can be discontinued on reaching the highest part of your colon (the cecum) so you can wake up and watch the procedure during the instrument withdrawal, which is generally not uncomfortable.
Most of our patients prefer not to remember their examinations. Sedation with propofol is more likely than conventional moderate endoscopic sedation (using midazolam-fentanyl) to succeed in providing a pain-free examination. It is very unusual for patients at our center to report the recall of any significant discomfort. It is important for you to discuss your preferences regarding your sedation with your doctor, who will work with you to incorporate your wishes into your sedation plan.
While the medications we use are very short acting there are not adequate data in the medical literature to confidently determine when psychomotor function returns sufficiently to allow safe driving. We instruct you not to drive or operate potentially dangerous machinery until the day after your procedure.
Just as some patients ask not to remember anything, others want to see some or all of their exam. You should discuss this with your doctor before the examination. In most cases patients sedated with propofol can be allowed to awaken during the withdrawal of the colonoscope, once the cecum has been reached. Colonoscopy is not usually uncomfortable once the cecum has been reached.
Low dose midazolam and propofol do not cause nausea. Doctors can avoid administering fentanyl to patients who have severe sensitivity to opioid-type drugs (codeine, morphine, meperedine or Demerol, Lortab). Please let your physician know if you have a history of vomiting due to anesthesia or opioid drugs.
This is a common worry. It is not unusual for patients to become talkative when under the influence of sedative drugs, and they often are surprised to hear things that they chatted about as they were "going under," during the exam itself, or as they recovered.
These symptoms are not expected and should be reported immediately to your physician. If you also have throat, neck, chest or abdominal pain or tenderness, an endoscopic complication such as perforation or splenic injury must be assumed to have occurred until proven otherwise. Early diagnosis and treatment is key to achieving the best outcome. If you have no other symptoms your fever, chills and body aches may be due to the sedative administered for your procedure, particularly if you received propofol. The FDA and CDC are investigating clusters of propofol-associated fever from around the country. Evaluation and treatment for bacterial sepsis is recommended if this problem is suspected.