Hypotension on Induction
Conditions
Keywords
Intraoperative hypotension
Brief summary
Intrathoracic pressure regulation (IPR) therapy, delivered by impedance threshold devices (ITDs) or intrathoracic pressure regulators (ITPRs), increases venous return, preload, cardiac output, blood pressure, and cerebral perfusion pressure by intermittently creating negative intrathoracic pressure, which improves circulation in hypotensive animals and humans. By increasing systemic pressure and cerebral perfusion as well as promoting venous return, IPR therapy potentially improves cerebral oxygenation. The lower intrathoracic pressures may also reduce pulmonary artery pressure, although there is currently little evidence one way or the other. Use of an ITPR can counteract the multifactorial intraoperative hypotension common during surgeries under general anesthesia, and reduce the need for other measures to treat such hypotension; however, they might simultaneously promote pulmonary complications. The investigators will therefore assess whether the use of intrathoracic pressure regulation in adults having shoulder surgery under general anesthesia in the sitting position reduces vasoactive medication requirements compared with routine clinical practice. Simultaneously, the investigators will assess the effect of intrathoracic pressure regulation on pulmonary circulation, cerebral oxygenation, and postoperative atelectasis.
Interventions
DEVICECirQPOD
CirQPOD is connected between the wye piece on ventilator/anesthesia machine tubing and the patient's airway and generates negative intrathoracic pressure during the expiratory phase of ventilation which has been shown to improve blood flow.
Standard airway management during surgery (PEEP of +5 cmH2O)
Sponsors
Zoll Medical Corporation
The Cleveland Clinic
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age ≥18 years * American Society of Anesthesiologists (ASA) physical status class ≤3 * Scheduled for surgery in sitting/ beach-chair positions under general anesthesia in the Cleveland Clinic main campus * Planned length of surgery \>60 minutes
Exclusion criteria
* Severe peripheral vascular disease or other contraindication for use of vasopressor infusion * Obstructive lung disease - moderate or severe asthma or COPD * Baseline hypoxemia (SpO2\<92% on room air) * Body Mass Index (BMI) \>35 * Congestive heart failure * Pneumothorax or hemothorax * Uncontrolled hemorrhage * Planned intraoperative hypotension * Contraindication to trans-esophageal echocardiography (esophageal stricture, surgery involving the esophagus or stomach)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Phenylephrine use | from device placement to start of wound closure, a period of up to four hours | Amount of phenylephrine required to maintain MAP of 80±5 mmHg |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pulmonary artery pressure | at least two minutes after IPR level of -10 cmH2O has been set | pressure in the pulmonary artery as measured by transesophageal echocardiography (TEE) |
| Atelectasis | first day post-op | presence and amount of atelectasis as determined by chest computerized tomography (CT) |
| PaO2 | at least 20 minutes, but not more than 2 hours, after patient is free of oxygen supplementation | post-operative partial arterial oxygen pressure measured by arterial blood gas (ABG) |
Countries
United States
Outcome results
None listed