Definition
The saddle block is a special form of anaesthesia that has a relatively limited effect on the external genitals, anus, pelvic floor and perineum. This anaesthesia is therefore particularly popular in gynecology, urology and proctology.
What is a saddle block?
The saddle block is a special form of spinal anesthesia. The sacral segments of the spinal canal are particularly affected. A distinction is made between the genuine saddle block, also known as breeches anesthesia, and the extended saddle block, which also reaches lumbar segments.
The real saddle block is used in proctology, gynecology and obstetrics, as well as in urology, since the anus, perineal area, pelvic floor muscles and the external genitals are anaesthetized. Operations on abdominal organs are only permitted with the extended saddle block. It is a relatively safe procedure with similar side effects to normal spinal anaesthesia, but these side effects are usually mitigated. This topic could also be interesting for you: What is a spinal anaesthesia?
Indications for a saddle block
Since the real saddle block only numbs the external genitals, anus, pelvic floor and perineum, the indications are relatively limited. The saddle block can be used in obstetrics, for surgical procedures on the anus, for example, removal of hemorrhoids, and also for tumor removal of the skin and mucous membrane. With the extended saddle block, operations on the lower abdominal organs, such as the uterus, can also be performed. As a general rule, the least invasive method should always be chosen for anaesthesia. For this reason, the saddle block is very well suited for the procedures described above, since a larger anaesthetic field is not necessary.
Passage of the saddle block
In all anaesthesiological procedures, the patient’s education is the first priority. Here the patient should also have the chance to ask questions. The actual execution takes place with the sitting patient.
In rare cases, a lateral position can also be used. For the puncture, the intervertebral space between lumbar vertebrae three and four or four and five is chosen. The area is thoroughly disinfected, as no germs may enter the spinal canal.
First the skin is punctured and then the ligamentous apparatus of the spinal column. Finally, the hard skin of the spinal cord is punctured. The draining of spinal fluid serves to control the position of the spinal cord.
The local anesthetic is injected under even and gentle pressure. Since the drug is somewhat heavier than the spinal fluid, it automatically sinks to the bottom of the spinal cord when the patient is sitting. For this reason, the patient should remain in a seated position after the injection until the effect has set in.
Lying down after half a minute leads to the extended saddle block. After about a quarter of an hour, the effect should be complete. For the saddle block, the same drugs are used as those used in spinal and regional anesthesia.
Some examples of local anesthetics used are lidocaine, bupivacaine and ropivacaine. All these drugs act in a similar way to their historical origin, cocaine. The different local anesthetics differ in their duration of action, strength and onset of action.
In some cases mixtures of different preparations are used, so that the respective advantages can be used. The dosage depends on many individual factors. Height and weight play a role here, as the distribution space for the drug increases with height.
Exactly which drug is used also determines the dosage. It is therefore not possible to give an exact dosage. Since some factors cannot be planned in advance, a second dose may be necessary if the first dose is not sufficient.
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