Cardiovascular considerations in patients undergoing gastrointestinal endoscopy

Novel Oral Anticoagulants in the Peri-Endoscopic Period

Millions of patients in the United States are currently prescribed some form of anticoagulation therapy. Recently, novel oral anticoagulants (NOACs), including direct thrombin inhibitors and direct factor Xa inhibitors, have begun to replace warfarin as the drugs of choice for anticoagulation. As the use of these medications becomes more widespread, it is increasingly important for gastroenterologists to understand the risks associated with performing endoscopic procedures on patients who are taking NOACs. In this review, we provide an overview of the NOACs and current guidelines from international societies regarding the management of patients scheduled to undergo endoscopic procedures who are prescribed these medications. Finally, we offer a perspective on future studies required to adequately investigate and characterize the effects that these drugs have on a patient's risk for bleeding in the peri- and/or postprocedural timeframes.

Preprocedural Assessment for Sedation in Gastrointestinal Endoscopy

The role of the anesthesia service in sedation for gastrointestinal endoscopy (GIE) has been steadily increasing. The goals of preprocedural assessment are determined by the specific details of the procedure, the issues related to the illness that requires the endoscopy, comorbidities, the goals for sedation, and the risk of complications from the sedation and the endoscopic procedure. Rather than consider these issues as separate entities, they should be considered as part of a continuum of preparation for GIE. This is told from the perspective of an anesthesiologist who regularly participates in the full range of sedation for GIE.

Nonoperating room anesthesia for the gastrointestinal endoscopy suite

Anesthesia services are increasingly being requested for gastrointestinal (GI) endoscopy procedures. The preparation of the patients is different from the traditional operating room practice. The responsibility to optimize comorbid conditions is also unclear. The anesthetic techniques are unique to the procedures, as are the likely events that require intervention by the anesthesia team. The postprocedure care is also unique. The future needs for anesthesia services in GI endoscopy suite are likely to expand with further developments of the technology.

Double balloon enteroscopy examinations in general anesthesia

AIM

To demonstrate that the double balloon enteroscopy (DBE) can be safely performed in general anesthesia with intubation.

METHODS

We performed a retrospective examination between August 2005 and November 2008 among patients receiving intubation narcosis due to DBE examination. The patients were grouped based on sex, age and physical status. Anesthesia records included duration of anesthesia, quantity of medication used and anesthesia-related complications. We determined the frequency of complications in the different groups and their relation with the quantity of medication used and the duration of anesthesia.

RESULTS

We compiled data for 108 cases of general anesthesia with intubation. We did not observe any permanent anesthesia-related complications; the most frequent side effects of anesthesia were hypotension (30.55%), desaturation (21.29%), and apnea (17.59%). These complications were significantly more frequent among patients with multiple additional diseases [hypotension (23.1% vs 76.9%, P = 0.005), de-saturation (12.3% vs 69.2%, P < 0.001) and apnea (7.7% vs 53.8%, P = 0.001)], however, their incidence was not proportional to the quantity of medication used or the duration of anesthesia.

CONCLUSION

General anesthesia with intubation is definitely a viable option among DBE methods. It is highly recommended in patients with multiple additional diseases.

[Anticoagulation and antiplatelet therapy, and gastrointestinal endoscopy]

Over the past decade, the application of anticoagulant and antiplatelet agents for various cardiovascular and hematologic conditions has become more widespread. These medications can decrease the risk of thromboembolic events, meanwhile may potentiate gastrointestinal bleeding. The decision to reverse anticoagulation, thereby risking thromboembolic complications, must be carefully weighted against the increased risk of bleeding when maintaining anticoagulation. Elective procedures should be delayed in patients on temporary anticoagulation therapy (e.g. those with deep vein thrombosis). For procedures considered to have a low risk of bleeding (e.g. diagnostic endoscopy and biopsy) there is no need to discontinue or adjust anticoagulation. For procedures with a higher risk of bleeding (e.g. polypectomy and biliary sphincterotomy), an individual approach is required. This approach might include stopping oral anticoagulant therapy with or without the administration of unfractionated heparin or low-molecular-weight heparin for the pre-procedure and post-procedure periods, during which the patient's international normalized ratio is in the subtherapeutic range. Antiplatelet drugs (aspirin, clopidogrel, ticlopidine) may also increase the risk of bleeding induced by gastrointestinal endoscopic procedures. There is no indication to stop the therapy before esophagogastroduodenoscopy. Discontinuation of aspirin 4-7 days (according to the cardiovascular risk) before other endoscopic procedures is recommended. When aspirin is indicated for primary prevention, it can be resumed 14 days and 10 days after polypectomy and sphincterotomy, respectively. In cases of secondary prevention, it should be resumed after 1 week.

Continuous non-invasive arterial pressure technique improves patient monitoring during interventional endoscopy

INTRODUCTION

Close monitoring of arterial blood pressure (BP) is a central part of cardiovascular surveillance of patients at risk for hypotension. Therefore, patients undergoing diagnostic and therapeutic procedures with the use of sedating agents are monitored by discontinuous non-invasive BP measurement (NIBP). Continuous non-invasive BP monitoring based on vascular unloading technique (CNAP, CN Systems, Graz) may improve patient safety in those settings. We investigated if this new technique improved monitoring of patients undergoing interventional endoscopy.

METHODS

40 patients undergoing interventional endoscopy between April and December 2007 were prospectively studied with CNAP(R) in addition to standard monitoring (NIBP, ECG and oxygen saturation). All monitoring values were extracted from the surveillance network at one-second intervals, and clinical parameters were documented. The variance of CNAP values were calculated for every interval between two NIBP measurements.

RESULTS

2660 minutes of monitoring were recorded (mean 60.1+/-34.4 min/patient). All patients were analgosedated with midazolam and pethidine, and 24/40 had propofol infusion (mean 90.9+/-70.3 mg). The mean arterial pressure for CNAP was 102.4+/-21.2 mmHg and 106.8+/-24.8 mmHg for NIBP. Based on the first NIBP value in an interval between two NIBP measurements, BP values determined by CNAP showed a maximum increase of 30.8+/-21.7% and a maximum decrease of 22.4+/-28.3% (mean of all intervals).

DISCUSSION

Conventional intermittent blood pressure monitoring of patients receiving sedating agents failed to detect fast changes in BP. The new technique CNAP improved the detection of rapid BP changes, and may contribute to a better patient safety for those undergoing interventional procedures.