Abstract 27: A Novel Intrathoracic Pressure Regulator Improves Hemodynamics in Hypotensive Patients During Surgery
Background: Intraoperative hypotension (IH) is common during surgery and may be associated with significant morbidity and mortality. The Intrathoracic Pressure Regulator (ITPR) is a non-invasive device to improve circulation and hemodynamics (HD) in patients intubated with oroendotracheal tubes. The ITPR is placed between the endotracheal tube and a standard respiratory circuit and acts by decreasing intrathoracic pressure to sub-atmospheric levels during the expiratory phase of each mechanical positive pressure breath. The decreased pressure enhances venous return, lowers intracranial pressure, and increases blood flow to vital organs as shown in animal models. We hypothesized that the ITPR would improve blood pressure in hypotensive patients during surgery.
Methods: Consenting adult patients ASA class 1–3, undergoing elective abdominal/pelvic surgery, were routinely monitored after anesthesia induction, intubation and initiation of mechanical ventilation. If IH occurred > 10 minutes following initial induction (SBP < 90 mm Hg or 20% decrease from baseline), the patient was enrolled and the ITPR was initiated for at least 10 minutes. Data were recorded every 2 minutes and were acquired prior to administration of any i.v. fluid bolus or vasopressors. Repeated measures ANOVA with Dunnett multiple comparisons test was used to determine statistical significance (p <0.05).
Results: Ten patients were enrolled reflecting 12 IH events. Mean age was 58.8 ± 11.3 years (range= 38–74, 8 female) and mean weight was 74.8 ± 11.0 kg. See table. In 7/12 events, no additional therapy was required for management of IH. There were no adverse events.
Conclusion: ITPR therapy improved HD as manifested by a significant increase in SBP, DBP, and MAP, whereas HR increased only slightly. ITPR therapy can be a safe, effective, non-pharmacologic, non-fluid loading approach for treating IH. Further studies are warranted to determine optimal patient selection and treatment parameters.
- © 2010 by American Heart Association, Inc.