The aim of anesthesia is to prevent pain during a medical procedure. But what is pain? One woman does not move a muscle during the procedure and walks away without discomfort . But later she may complain bitterly about the pain she suffered. Another woman keeps yelling during the procedure but she says later that she felt almost nothing. Most patients are somewhere in between, expressing more or less pain. There is no direct relationship between the ease of the procedure and the reported pain. A difficult procedure requiring much force in dilation may be painless while a very smooth procedure may cause much pain. In the latter case the doctor may get irritated and rebuke the patient for exaggerating, which only makes the matter worse. The most important way to prevent pain is a careful counseling before the procedure and careful attention during the procedure.

In some cases the procedure may be done under local anesthesia only, especially if the pregnancy is about 8 to 12 weeks. In a younger pregnancy the dilation may cause more pain, in a more advanced pregnancy the duration of the procedure may be exhausting. In the advanced pregnancy a local anesthetic with nor- adrenaline as a vasoconstrictor is recommended. (do not use adrenaline as this causes tachycardia that may cause panic) In a number of cases a so-called augmented local anesthesia is advisable, this is local anesthesia combined with a suitable pre medication .

Since the beginning of this century general anesthesia is desired. Since only a very light general anesthesia is feasible which has no analgesic properties the combination with local anesthesia or a painkiller, like members of the fentanyl family, is recommended, particularly in the case of an advanced pregnancy for the added advantage of vasoconstriction.

A procedure developed in the Netherlands in 2006 is the IV administered combination of midazolam (Versed®) 1 to 3 mg and alfentanil 1 mg ; this combination ('Rapidorm') gives a ± 3 minutes black out with amnesia and "absolute" absence of pain.

1. PREMEDICATION - It is advisable to give atropine 0.5 mg in all cases. It prevents or reduces vagal stimulation by handling the uterus (especially during dilation), like bradycardia, vomiting, fall of blood pressure and sweating. In general anesthesia it prevents or reduces salivation and mucus formation in the respiratory tract. Not everybody is convinced of the necessity in local anesthesia. At least a syringe containing atropine should be kept ready for I.V. administration in case of bradycardia. In an experiment where the ECG was taken in a series of patients with and without atropine Schlebaum found that the incidence of ECG changes, mainly bradycardia and reduction of PR time, was significantly more frequent if no atropine was given. Intramuscular administration of atropine has little or no effect since the compound is rapidly disintegrated within the muscle tissue.

In some patients local anesthesia is not sufficient to prevent pain, or the patient is scared or restless. In these cases a suitable pre medication can be given (augmented local). In the case of general anesthesia a suitable sedative should be given, and an analgesic if the general anesthesia is not combined with local. Fentanyl is a safe and effective analgesic. It may cause pain along the vein in which it is injected. Injection besides the vein is very painful. A possible side effect is respiratory depression. Although we have never seen this, naloxone should be kept ready as an antidote. More effective but with a shorter duration is alfentanil (rapifen ®). The last novelty is remifentanyl (Ultiva®) which is even stronger and shorter acting than alfentanil.

Sedation can be obtained by giving diazepam or midazolam 2 -5 mg IV. Diazepam has the disadvantage that certain products of metabolism produce undesirable effects several hours after the procedure. Midazolam lacks this disadvantage and has the advantage that it has a marked anterograde amnesia. This pre medication also prevents muscle movements caused by etomidate. Droperidol has a strong anti emetic action, and a anxiolytic effect as well. It may be given together with one of the other sedatives. Flumazenil may be used to reverse the sedative effects of benzodiazepines (diazepam and midazolam) if the patients sleeps too long. An ampoule should be kept ready for use if the effect of the pre medication is too strong. A dose of 0.2 mg (2 ml) is given slowly IV during 15 seconds. This may be repeated till the desired effect is reached. The maximum dose is 2 mg (20 ml).

In the advanced pregnancy (over 13 weeks) ergometrine and oxytocin are given to obtain a firm uterine wall. It is recommended to bring a venous canula into a suitable vein in all cases. Best is a type of canula with an injection valve, a side opening for a syringe, allowing injection without the risk of contaminating the syringe with blood. A suitable type is Venflon®. This allows repeated use of syringes and an intravenous injection can be given without delay if the need arises.

Anno 2010 we cannot finish this chapter without mentioning the use of propofol (Diprivan ®) as an anaestetic. The dosage is 6-12 mg/kg/hour. It has certain advantages over etomidate as patients are less drowsy postoperatively. TCI (target controlled infusion) icm Remifentanyl gives excellent results.

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last revision spring 2010