What are pacemaker-based hypertension therapy tampons

Post-bleeding lasting several days after removal of a root remnant

What happened?

In preparation for the surgical removal of a root remnant in region 43 and a sequester in region 26, the patient was asked to have his blood coagulation values ​​adjusted by a doctor because he was taking a vitamin K antagonist. The attending dentist asked for a Quick value of> 20 percent and an INR value of <3. The patient's history shows that the patient suffers from hypertension, type II diabetes and cardiac arrhythmias. He has a pacemaker and suffered a heart attack years ago.

On the day of the procedure, the Quick value was 51 percent and the INR value was 1.58. The patient was also prescribed injections with low molecular weight heparin (LMWH) by the family doctor, as the vitamin K antagonist had been discontinued a few days beforehand.

The root remnants and the sequestrants were removed without complications, the wounds were sutured and the patient was able to leave the practice at 9 a.m. The bleeding stopped completely at this point. The patient was instructed to intermittently cool the surgical areas.

At around 6 p.m. the patient entered the practice with severe secondary bleeding. Both wounds were stitched up again. He was instructed to continue cooling and eating soft foods. The next day the wounds were normal and there was no further bleeding. The following night bleeding occurred again, but when the patient came back to the practice the next morning, the bleeding stopped and no further therapy was given. Bleeding began again on the third postoperative day, after which the patient was referred to a surgical practice. There the wounds were exposed again, cleaned and sutured again. Only a few days later and after repeated bleeding did the bleeding finally stop.

What could have led to this event?

Postoperative bleeding events can have local or systemic causes. The treating dentist must take both aspects into account.

Possible local causes can be:

  1. Leaving inflammatory granulation tissue in place
  2. strong soft tissue mobilization in the suture technique (unnecessary periosteal slitting)
  3. Inadequate suture with a pronounced operating area
  4. Immediately after the operation due to insufficient hemostasis or vascular bleeding from bones or gingiva
  5. about two to six hours after the operation due to reactive hyperemia after the effect of the vasoconstrictor has subsided
  6. about 72 hours after the operation due to inflammatory or iatrogenic disintegration of the coagulum in the alveolus


Possible systemic causes can be:

  1. inadequate pain and blood pressure control, which can lead to blood pressure spikes
  2. Overlapping anticoagulation with heparin and vitamin K antagonist can lead to uncontrollable (over) dosing.
  3. Bridging the vitamin K antagonist with heparin without a "real indication"


In this particular case, no local abnormalities were reported. The wound has been closed so that a systemic cause can be suspected. The overlapping anticoagulation is systemically conspicuous - in this case the simultaneous anticoagulant residual effect of the vitamin K antagonist and the low molecular weight heparin. This phase is particularly difficult to control with regard to the effect on the coagulation system and is therefore unfavorable for an operation.

According to the AWMF guidelines, extractions and uncomplicated osteotomies are possible with an INR value of 2.0 to 3.5. With an INR value between 1.6 and 1.9, extensive surgical rehabilitation can be carried out. Nevertheless, due to the long biological elimination half-life of vitamin K antagonists, increased rebleeding must always be expected.

Anticoagulant

  • Low molecular weight heparins (LMWH) achieve their anticoagulant properties through an inhibitory effect on factor Xa.
  • In contrast to the vitamin K antagonists, thrombin is only inhibited to a small extent, depending on the LMWH, and the aPTT is only insignificantly influenced in therapeutic doses.
  • The monitoring of the low molecular weight heparins cannot therefore take place via the INR value or the aPTT, but - only if necessary - via the anti-factor Xa activity.

How could the event have been avoided?

The consultation with the general practitioner that took place here is to be welcomed, but does not release the dentist from the co-assessment of the coagulation situation. According to the S3 guideline "Dental surgery with oral anticoagulation / inhibition of platelet aggregation", the following recommendation is made for vitamin K antagonists:

"Typical dental-surgical interventions such as tooth extractions, osteotomies, implantations or circumscribed soft tissue interventions should take place with ongoing therapy with vitamin K antagonists without bridging."

Fig. 2: Scheme of the procedure for the intended treatment of patients with oral anticoagulation / inhibition of platelet aggregation | Source: Peer W. Kämmerer

The low INR value of 1.58 (target INR 2–3) can result in a cardiac risk. Now, after consulting the family doctor, the possibly increased cardiac risk must be accepted. According to this, the extraction would have taken place and the marrowumarization would have been continued promptly, for example the next day without administration of heparin. In the event of an arrhythmia, a short “marrow pause” is scientifically justifiable.

In this case, the family doctor has already started the overlapping substitution with heparin (bridging). In addition, the consequences of bridging must therefore be assessed. If, in the opinion of the family doctor and dentist, as in this case, bridging is necessary due to the high cardiac risk, the operation should be postponed until the marrowoid ​​effect has almost completely subsided and one can operate under the controllable heparin effect. Operations in the overlapping phase with the residual effect of the vitamin K antagonist and the effect of the heparin are in most cases uncontrollable and should only be carried out in an emergency with specialist medical treatment.

Conclusion

The dentist who carries out surgical measures under anticoagulation must be able to assess the patient's internal medical history. An INR of 1.58 is tolerable for tooth extractions and small osteotomies in a patient with atrial fibrillation. The consultation with the family doctor represents only part of the care required for such a treatment. The surgeon is responsible for assessing the current, individual and local bleeding risk. In view of the current S3 guideline, the frequency with which general practitioners still switch coumarin administration to heparin (bridging) is surprising.

CIRS dent - every tooth counts!

So I can take part

"CIRS dent - Every tooth counts!" (CIRS: Critical Incident Reporting System) is an online reporting and learning system from dentists for dentists. On the website www.cirsdent-jzz.de, registered colleagues can report, inform themselves and exchange ideas on a voluntary basis, anonymously and free of sanctions, about undesirable events from their everyday practice.

The aim is to learn from our own experiences and those of other dentists. In this way, every participant makes an active contribution to improving patient safety. 6,019 dentists have already registered and posted around 176 reports. Take part too - it's worth it!

To request a new registration key, for example in the event of a loss, practice owners can contact their responsible Association of Statutory Health Insurance Dentists (KZV) or [email protected] Private dental colleagues and the heads of university dental facilities receive the registration key from their (regional) dental association. The members of the Bundeswehr receive their registration keys from their site managers.

Despite everything, unexpected bleeding events can occur due to the individual physiological situation of the patient. Even in patients with a low INR value, rebleeding can occur due to the prolonged half-life of coumarin. In these foreseeable cases, there should also be a strategy for blood coagulation. In addition to the adapting sutures, this includes dressing plates, tamponades, hemostyptics and, if necessary, devices for bipolar hemostasis. Mouthwashes with 5 percent tranexamic acid, fibrin or cyanoacrylate glue or the inlay of bone wax offer further options.

In the event of further serious, therapy-refractory bleeding, the possibility of acquired inhibitory hemophilia with pre-existing anticoagulation should always be considered.

Further help:
Univ.-Prof. Dr. Dr. Bilal Al-Nawas
Director of the Clinic for Oral and Maxillofacial Surgery, Plastic Surgery,
Oral and maxillofacial surgeon
Augustusplatz 2, 55131 Mainz
[email protected]

One becomes wise from this damage

Errors occur wherever people work - dentists are no exception: processes do not always work as they should, diagnoses are sometimes not easy to make, therapies fail for unexpected reasons, devices and aids show weaknesses. The list of possible “adverse events” that can occur in practice is long.

However, one can learn from “adverse events” to do better in the future. Exchanging experiences with colleagues is helpful. At the beginning of 2016, the German Dental Association and the National Association of Statutory Health Insurance Dentists launched the internet-based reporting and learning system “CIRS dent - Every tooth counts!” (CIRS = Critical Incident Reporting System). There, dentists can read case reports from colleagues' practices and also post their own reports completely anonymously. The reports sent are checked by a specialist editorial team and processed if necessary.

Data that could be traced back to the practice or the patient are removed and the reports are only published afterwards. In the section "The special case from CIRS dent" we publish case descriptions that are of general interest.