Low-dose rate implants
High-dose rate implants
Lower dose of radiation requiring more treatments
Higher dose of radiation requiring a shorter period of treatment (e.g., 5–10 min). Newer method that has the advantage that staff does not get exposed to radiation
May be permanent seeds or involve temporary applicator placement for a period of time
Implantation and treatment done in several sessions and involves temporary placement of an applicator. The applicator may be implanted over a period of days for daily treatments or removed and replaced weekly for weekly treatments
External Beam Radiation uses a machine to deliver radiation from outside of the body.
Usually several treatments are required.
Treatments are not painful.
The anesthesia provider should formulate the anesthetic plan after discussing the needs of the procedure and patient.
Applicator placement and removal may be painful .
There is a wide range of options of anesthetic techniques for brachytherapy procedures. See Table 25.2 for a summary of advantages and disadvantages. Considerations for choosing a technique include:
Patient specific, such as a patient who is morbidly obese, has risk factors for aspiration, or a known or suspected difficult airway. Non-breast patients undergoing brachytherapy are usually older and sicker and may not be candidates for major surgery [1, 4].
Length of procedure. Brachytherapy can be lengthy because of the need to confirm placement of the applicator and perform calculations prior to treatment .
Immobility to ensure proper placement of the applicator and whether the patient will need to remain immobile after the procedure.
Whether the patient will need to be transported to a scanner or radiation room while anesthetized .
If a patient is under general anesthesia, ensure that a ventilator and full monitoring are available in these other areas.
Use of a camera on the patient and monitors or use of slave monitor during treatments. Rooms are shielded and should be fully equipped with anesthesia equipment.
Minimize post-operative nausea and vomiting.
Operating/procedural room environment and infrastructure.
Possible influence of anesthetic technique on outcome of brachytherapy, although few randomized controlled trials exist.
Local anesthesia for Brachytherapy
Used widely by radiotherapists. Although more effective than placebo, pain has been found to exist after this technique, as it is often performed without anesthesia staff present [1, 5].
Also likely to result in inferior applicator placement because the patient may move from insufficient analgesia .
Sedation for Brachytherapy
Regional anesthesia for Brachytherapy
Used mainly for brachytherapy of the lower body, including patients with urological, lower rectal, and gynecologic cancers.
Advantages of regional anesthesia include sufficient analgesia and immobilization, high degree of patient satisfaction, and safer transfer of patients between different sites of care .
Options for regional anesthesia include spinal, lumbar epidural, caudal, and combined spinal-epidural techniques .
Spinal anesthesia represents high proportion of patients receiving regional anesthesia for brachytherapy . Advantages of spinal anesthesia include rapid onset and known duration of anesthesia .
Combined spinal-epidural or solely an epidural may be a better choice for longer procedures.
Caudal epidural blocks have been described for gynecological brachytherapy. Its disadvantages include its technical difficulty in placing the block especially in obese patients, its limited duration and insufficient analgesia for applicator placement .
Lumbar epidural catheter technique is popular for gynecological, urological and rectal cases. When compared to epidural patient-controlled analgesia in patients who underwent HDR of the prostate, it was shown to be significantly superior [1, 9]. It may also offer the advantage of providing analgesia during applicator removal when bolused .
A retrospective review of over 5000 brachytherapy cases found regional anesthesia performed in 30 % of lower body brachytherapy cases and in the majority of pelvic brachytherapy cases .
General anesthesia for Brachytherapy
Indications for general anesthesia include brachytherapy for malignancies of upper body (e.g., oropharyngeal cancer, bronchus carcinoma), patient choice, and patients with contraindications to regional anesthesia [1, 4].
Some institutions like ours prefer general anesthesia for all brachytherapy cases. An MRI and CT scanner equipped with our anesthetic monitors, ventilator and equipment are readily available allowing for easy and safe transport. Our patients are transported and recovered in the PACU.
General anesthesia requires more preparation and equipment. For example, if a patient is to have a CT or MRI, a ventilator will be necessary in both the brachytherapy suite and scanner.
When selecting an anesthetic technique, it is important to keep in mind that many brachytherapy patients are considered ASA III or IV and are over the age of 60 years .
Overall, complications from both regional and general anesthesia techniques are minor and include hypotension, bradycardia, and postoperative nausea and vomiting .
Studies in this area show no significant difference between general and regional anesthesia techniques in postoperative complications or satisfaction [1, 10]. A prospective trial in this area compared patients receiving four different anesthetic techniques: general anesthesia with TIVA, general anesthesia with isoflurane, small dose spinal block, or large dose spinal block. The TIVA technique was found to have earliest voiding and fastest discharge of all techniques, although there was no difference in any choice on the outcome of postoperative nausea or vomiting, pain score, return to normal function at home, or overall patient satisfaction .
Retrospective review of general anesthesia versus regional anesthesia in prostate brachytherapy showed no correlation between anesthetic technique and postoperative prostate gland swelling, acute toxicity, or implant dosimetric quality .
In patients without an epidural catheter, acetaminophen, morphine, codeine, and NSAIDS may be considered for postoperative analgesia .
If applicators remain in the patient, the patient may experience discomfort and may need to be immobilized while in the hospital.