Percutaneous Endoscopic Gastrostomy (PEG) Tube Placement in Patients with Continuous-Flow Left Ventricular Assist Devices (LVAD)

Introduction: Inadequate nutritional support after LVAD placement is known to increase postoperative infections and to decrease survival. LVAD patients with prolonged mechanical ventilation and complicated postoperative recovery requiring prolonged mechanical ventilation may require long-term tube feedings. Placement of a PEG requires knowledge of the location of the LVAD pocket and driveline to avoid device infection and injury. Methods: Between August 2008 and December 2011, 39 patients underwent HeartMate II LVAD placement in our institution. Among them, 5 patients underwent PEG tube placement for long-term nutritional support. Procedure management consisted of cessation of anticoagulation and correction of abnormal coagulation; a cardiothoracic surgeon or intensivist in the operating room to communicate with the surgeon who performed the PEG procedure; and VAD coordinator or perfusionist in the operating room to assist in monitoring the VAD. Data were retrospectively analyzed to investigate complications related to the PEG placement. Results: The studied patients consisted of 3 males and 2 females with mean age of 58 +/﹣5.0. The interval of LVAD to PEG placement was a mean 21 +/﹣8.8 days. PEG was successfully performed in the operating room in all patients. There were no LVAD device or driveline injuries related to the PEG procedure. There were no postoperative short-term or long-term PEG related complications such as acute gastric bleeding or dislodgement of the PEG tube. Conclusions: PEG placement for HeartMate II LVAD patients can be done without increasing the risk of device or intraabdominal organ injury with carefully coordinated efforts from both the mechanical support team and surgical services.


Introduction
Inadequate nutritional support after LVAD placement is known to increase postoperative infections, to prolong hospitalization, and to decrease survival. The patients in this study had a complicated postoperative recovery period after receiving HeartMate II left ventricular assist devices (LVADs) requiring prolonged mechanical ventilation, which required long-term nutritional support. Post-operative patients with newly implanted LVADs run a high risk of infection, especially with multiple drug-resistant organisms [1]. This patient population's increased susceptibility to infection makes infection prevention one of the top treatment objectives. A stable nutritional status can be the foundation to achieve this goal. Many protocols designed to provide this platform involve the use total parenteral nutrition (TPN) or a nasogastric tubes (NGT) for long-term feedings.
Both modalities of TPN and NGT tube feeding carry the risk of multiple complications. TPN brings with it a host of complications, including parenteral-associated liver disease and a higher rate of blood-stream infections (BSI), to name a few [2]. The central venous catheters (CVC) required to provide TPN are a direct source of infection, and the number of CVC days in an intensive care unit (ICU) is directly linked to increased rates of bacterial and fungal BSI [3][4][5]. While NGTs have a lower risk of BSI, they do present with higher risk of aspiration pneumonia, esophagitis, and gastrointestinal bleeding (GIB) [6]. Patients receiving the HeartMate II LVAD are already at an increased risk of GIB; so another route of nutritional support was sought [7].
Percutaneous endoscopic gastrostomy (PEG) tubes are considered as a viable alternative to NGT and TPN for long-term nutritional support. Due to the anatomical position of the LVAD pocket and drivelines, the PEG tube placement procedure has the potential to disrupt the aforementioned structures. The potential of an infection at the PEG site compromising the LVAD device is a valid concern. In addition, patients with LVADs require constant anticoagulation. Titrating patients off anticoagulation lead to a concern for thromboembolic events and pump thrombosis. While the HeartMate II LVAD pump has a low rate of thromboembolic events and pump thrombosis, there have been cases of these events occurring [8]. There has been a concern in the past for intraoperative and post-operative bleeding associated with the PEG placement procedure when anticoagulation is continued. At our institution, an LVAD anticoagulation protocol was established to allow for PEG placement with minimal complications. The current study was performed to investigate the feasibility of PEG placement while on anticoagulation for a LVAD.

Methods
Between August 2008 and December 2011, 39 patients underwent HeartMate II LVAD (Thoratec Co, Pleasanton, CA) placement for end-stage heart failure as either bridge to transplant or destination therapy in our institution. Among them, 5 patients underwent PEG tube placement for long-term nutritional support in the operating room or intensive care unit. Procedure management consisted of cessation of anticoagulation and correction of abnormal coagulation before the procedure; a cardiothoracic surgeon or intensivist in the operating room to communicate with the surgeon who performed the PEG procedure; and VAD coordinator or perfusionist in the operating room to assist in monitoring the VAD. Data were retrospectively analyzed to investigate complications related to the PEG placement. This study was approved by internal review board.

Results
The studied patients consisted of 3 males and 2 females with mean age of 58 +/− 5.0. The interval of LVAD to PEG placement was a mean 21 +/− 8.8 days ( Table 1). PEG was successfully performed in the operating room or intensive care unit in all patients. There were no LVAD device or driveline injuries during the PEG procedure. There were no postoperative short-term or longterm PEG related complications such as acute gastric bleeding or dislodgement of the PEG tube. No patient developed aspiration pneumonia related to PEG tube feeding after PEG placement (Figure 1).

Discussion
Patients with LVADs receiving a PEG tube for long-term nutritional support with must be maintained on a minimal amount of anticoagulation to prevent thromboembolic events and pump thrombosis while not increasing the risk of bleeding. Thrombotic events must be carefully watched for in continuous-flow LVADs, like the HeartMate II, even though they have lower rates of these complications than the pulsatile flow LVADs [9]. Thrombotic events are not solely feared for their compromise of circulation, but are also linked to increased rates of infection [10]. Bacterial and fungal insults can wreak havoc in LVAD patients causing a multitude of complications that increase morbidity and mortality. One of the main purposes of this study was to reduce the already established infectious risk correlated with CVC required for TPN and gastro-enteric compromise associated with NGTs. One case series elucidated the threat of gastrointestinal-tract fistulas causing critical infections of the LVAD pocket [11]. One can only imagine with the anatomic location of an NGT in the stomach and LVAD pocket within the abdomen, how a small erosion caused by the NGT in the gastric mucosa could communicate with the LVAD pocket. This in turn could lead to devastating rise in infection rates among these patients.
This study provided an alternative nutritional route without direct complication. This was achieved by balancing anticoagulation and hemostasis to prevent intraoperative and post-operative morbidity and mortality in the placement of a PEG tube in patients with LVAD devices. Intra-operative and post-operative bleeding are two immediate concerns in patients on chronic anticoagulation. Compound this with the already existing increased rate of GI bleeding with LVADs, and clinical management becomes more difficult [7]. The anticoagulation protocol followed in this study provided five LVAD patients with PEG tubes without GI bleeds or any other complication related to the PEG procedure.

Conclusion
PEG placement for HeartMate II LVAD patients can be done without increasing the risk of device or intraabdominal organ injury with carefully coordinated efforts from both the mechanical support team and surgical services.