None listed
Conditions
Brief summary
Low cardiac output (CO) is common post cardiac surgery and associated with increased morbidity and mortality, ICU length of stay and healthcare costs. Optimising heart rate with atrial pacing may result in improved cardiac output. We hypothesise that increasing heart rate via atrial pacing in post-operative cardiac surgery patients will increase cardiac output until an optimal heart rate is reached at which point further increases will not increase cardiac output. This study will aim to provide information regarding the optimal heart rate, through the use of existing atrial pacing wires and measure cardiac index via pulmonary artery catheters.
Interventions
Study evaluating patients with pacing wires and pulmonary artery catheters post cardiac surgery. This will be performed after the patient has been admitted to the intensive care unit and the treating Intensivist feels the patient is clinically stable and euvolaemic.
Intensive care doctor will administer the intervention. There will be a paper form for each patient with the schedule of heart rates, duration and instructions.
Evaluating the Cardiac Output response to Different pacing rates (60
Study evaluating patients with pacing wires and pulmonary artery catheters post cardiac surgery. This will be performed after the patient has been admitted to the intensive care unit and the treating Intensivist feels the patient is clinically stable and euvolaemic. Intensive care doctor will administer the intervention. There will be a paper form for each patient with the schedule of heart rates, duration and instructions. Evaluating the Cardiac Output response to Different pacing rates (60, 75, 90, 110.) HR set at 90 (atrially paced) and then Cardiac Index measured at 10 minutes Then HR at 60 for 10 minutes and measure cardiac index at 10 minutes Return to 90 for 5 minutes (baseline) Then HR at 75 for 10 minutes and measure cardiac index at 10 minutes Return to 90 for 5 minutes then HR set to 110 for 10 minutes and cardiac index measured at 10 minutes In total the intervention and measurement period will take 50 minutes Where Atrio-Ventricular conduction block exists, patients will have both atrial and Ventricular wires, The same 4 heart rates will be selected - 60, 75,. 90, 110 and the same process adhered to but will require 2 chamber pacing so the pacing box setting will be DDD rather than AAI. In order to compare to ventricular pacing alone a convenience subset of 20 patients with atrial and ventricular wires will have ventricular pacing alone at 75 and 90 beats per minute to compare with the corresponding pacing with the atrial wire. This is a secondary exploratory outcome. These patients will be chosen based on availability of staff. This will occur immediately after the first set. The duration of 75 and 90 will be the same as the rest of cohort. The study member applying the intervention will remain at the bedside for the duration of the intervention and ensure adherence to the protocol
Sponsors
Sir Charles Gairdner Hospital
Study design
Allocation
Non-randomised trial
Intervention model
Other
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. Post cardiac surgery 2. Presence of pulmonary artery catheter and pacing wires 3. Over 18 years of age
Exclusion criteria
Treating clinician feels the intervention should not be applied due to haemodynamic stability or other concern Absence of pacing wire or pulmonary artery catheter Baseline (intrinsic) tachycardia >90
Outcome results
None listed