Impact of practice patterns in shunt use during carotid endarterectomy with contralateral carotid occlusion
Philip P Goodney1, Jessica B Wallaert, Salvatore T Scali
1Section of Vascular Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, NH; Dartmouth-Hitchcock Medical Center, The Dartmouth Institute for Health Policy and Clinical Practice, Hanover, NH, USA. philip.goodney@hitchcock.org
Insights
Surgeons who routinely use shunts during carotid endarterectomy (CEA) have lower stroke/death rates in patients with contralateral carotid occlusion (CCO). Selective shunt use in CEA for CCO is associated with increased complications.
Area of Science:
- Vascular Surgery
- Cerebrovascular Surgery
- Surgical Outcomes Research
Background:
- Carotid endarterectomy (CEA) is a procedure to remove plaque from carotid arteries.
- Contralateral carotid occlusion (CCO) presents unique challenges during CEA.
- The role of shunting in CEA with CCO and its association with surgeon practice patterns requires investigation.
Purpose of the Study:
- To investigate the association between surgeon practice patterns in shunt placement and 30-day stroke/death rates in patients undergoing CEA with CCO.
- To compare stroke/death rates in patients with CCO versus those with a patent contralateral carotid artery.
Main Methods:
- Retrospective analysis of 6379 CEAs from the Vascular Study Group of New England (2002-2009).
- Identified 353 patients with CCO and compared them to 5279 patients with patent contralateral arteries.
- Examined 30-day stroke/death rates based on reason for shunt placement and surgeon practice patterns (selective vs. routine shunt use).
Main Results:
- Patients with CCO had a higher 30-day stroke/death rate compared to those with patent contralateral arteries.
- Surgeons who routinely used shunts (>95% of CEAs) had lower stroke/death rates (1.5%) in CCO patients compared to selective shunt users (5.6%).
- Risk-adjusted analysis showed higher risk for selective shunt users (O/E ratio 1.4) and lower risk for routine shunt users (O/E ratio 0.4).
Conclusions:
- CEA in patients with CCO is associated with a higher risk of 30-day stroke/death.
- Selective shunt placement by surgeons during CEA for CCO is linked to increased stroke/death rates.
- Routine shunt use by surgeons during CEA is associated with fewer complications, particularly in patients with CCO.
Purpose:
This study investigated the association between surgeon practice pattern in shunt placement and 30-day stroke/death in patients undergoing carotid endarterectomy (CEA) with contralateral carotid occlusion (CCO).
Methods:
Among 6379 CEAs performed in the Vascular Study Group of New England (VSGNE) between 2002 and 2009, we identified 353 patients who underwent CEA with CCO and compared the 30-day stroke/death rate with 5279 patients who underwent primary, isolated CEA with a patent contralateral carotid artery. Within patients with CCO, we examined the 30-day stroke/death rate across the reason for shunt placement and two distinct surgeon practice patterns in shunt placement: surgeons who selectively used a shunt (≤95% of CEAs) or routinely used a shunt (>95% of CEAs). We used observed/expected (O/E) ratios to provide risk-adjusted comparisons across groups.
Results:
Of 353 patients with CCO, 118 (33%) underwent CEA without a shunt, 173 (49%) underwent CEA using a shunt placed routinely, and 62 (18%) had a shunt placed for a neurologic indication. Rates of 30-day stroke/death across categories of reason for shunt use were no shunt, 3.4%; routine shunt, 4.0%; and shunt for indication, 4.8% (P = .891). The risk of 30-day stroke/death was higher for surgeons who selectively placed shunts (5.6%) in all their CEAs and lower for surgeons who routinely placed shunts (1.5%, P = .05). The risk of 30-day stroke/death was >1 in patients undergoing selective shunting (O/E ratio, 1.4; 95% confidence interval [CI], 1.1-1.7) and <1 for surgeons who placed shunts routinely (O/E ratio, 0.4; 95% CI, 0.2-0.9). Stroke/death rates were lowest when individual surgeons' intraoperative decisions reflected their usual pattern of practice: 1.5% stroke/death rate when "routine" surgeons placed a shunt, 3.4% when "selective" surgeons did not place a shunt, and 7.6% stroke/death rate for "selective" surgeons who placed a shunt (P = .05 for trend).
Conclusions:
The risk of 30-day stroke/death is higher in CEA in patients with CCO than with a patent contralateral carotid artery. Surgeons who place shunts selectively during CEA have higher rates of stroke/death in patients with CCO. This suggests that shunt use for CCO during CEA is associated with fewer complications, but only if the surgeon uses a shunt as part of his or her routine practice in CEA. Surgeons should preoperatively consider their own practice pattern in shunt use when faced with a patient who may require shunt placement.