Critical Care Scenarios
Episode 20: Post-CABG emergencies with Kris Ramilo and Brendan Riordan
Looking at the workflow of a fresh post-op open heart surgery patient, as well as what to do when it devolves into cardiac tamponade, with (returning) guest Brendan Riordan, cardiothoracic ICU PA (@concernecus) at the University of Washington, and his NP colleague Kris Ramilo (@krsrml0).
[Audio quality was a bit dodgy in this one; sorry all!–eds.]
* Handoff from the OR to ICU team is a tricky time, and should ideally be somewhat formalized, involve both surgical and anesthesia teams at the bedside, and including talk about what happened, what they expect, and things to look out for.* The ERAS (Early Recovery After Surgery) protocol has entered the CT surgery world as ERACS, including post-op measures for typical cases such as reversal of neuromuscular blockade and a 4-hour target for extubation (versus the usual 6 hours). Most routine cases will aim to be “bloodless,” i.e. only transfusing autologous (“Cell Saver” blood), as transfusion of banked blood is considered an STS measure.* Milking or stripping chest tubes during the immediate post-op period to maintain patency may or may not be necessary as a routine practice, but should certainly be attempted if output drops or tamponade is suspected.* Point-of-care TTE is always difficult in these patients, due to their windows being obscured by dressings; the apical 4-chamber will often be the most useful view. When seriously considering graft failure, TEE may be valuable to diagnose graft failure (by noting regional wall motion abnormality), as well as appreciating cardiac tamponade. * As in all cases, tamponade in this setting is diagnosed by echocardiographic pericardial effusion plus signs of tamponade physiology (chamber collapse, etc), with the caveat that effusions may be loculated or unusual-appearing due to the recent violation of the pericardium.* With a PA catheter, remember that narrowing of the PA pulse pressure and convergence of the CVP and PA pressures (particularly via a falling PA pressure) is classic for tamponade physiology.* Resternotomy is not something to be undertaken lightly, but still must be performed immediately and aggressively when indicated. Close involvement with the surgical team is usually essential to make this decision.* Adding an inotrope can be somewhat diagnostic, as patients with mere myocardial stunning will improve, whereas patients with tamponade will generally have little response.* Give calcium chloride freely to the unstable post-cardiac surgery patient.* Be aggressive with fluid resuscitation and consider epinephrine up to 0.06–0.08 mcg/kg/min or dopamine (if you must) up to 3–5 mcg/kg/minute.* The purpose of reopening the chest is to avoid external chest compressions, which tend to abuse RCA grafts (which sit just below the sternotomy wires), and are generally ineffective anyway compared to internal cardiac massage, since the pressure chamber of the chest is not intact.* The role of the ICU team while the surgical team reopens the chest is typically to assist with sedation, ventilator management, and hemodynamics. Anesthesia may or may not be present but is often performing TEE.* Patients reopened at the bedside will often be left with open chests, and planned to return back to the OR for washout and closure the next day. Plan on prophylactic antibiotics (e.g. vancomycin).