Fluctuations in Spinal Cord Perfusion Pressure: a Harbinger of Delayed Paraplegia after Thoracoabdominal Aortic Repair

• Published in: Seminars in thoracic and cardiovascular surgery Vol. 29; no. 4; pp. 451 - 459
• Main Authors: Sandhu, Harleen K., MD, MPH, Estrera, Anthony L., MD, Evans, Jonathan D., MBChB, Tanaka, Akiko, MD, Atay, Scott, MD, Afifi, Rana O., MD, Charlton-Ouw, Kristofer M., MD, Azizzadeh, Ali, MD, Miller, Charles C., PhD, Safi, Hazim J., MD
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 2017
• Subjects: aneurysm; Cardiothoracic Surgery; delayed; neurologic deficit; paraplegia; spinal cord injury; SAP; paraplegia; Postoperative day; Intracranial hemorrhage; Spinal cord injury; DP; Mean arterial pressure; Systolic arterial pressure; COPS protocol; Mean spinal cord perfusion pressure; Chronic obstructive pulmonary disease; mSCPP; delayed, aneurysm; Somatosensory evoked potential; SP; SBP; Systolic blood pressure; Systolic spinal cord perfusion pressure; OR; Thoracoabdominal aortic aneurysm; POD; ROC; Peripheral arterial disease; Spinal cord perfusion pressure; TAAA; Distal aortic perfusion; IQR; SSEP; neurologic deficit; ICH; Delayed paraplegia; DAP; PAD; Blood pressure stabilization, cerebrospinal fluid draining and O2 delivery; Receiver operating characteristic; SCPP; Interquartile range; sSCPP; MEP; Odds ratio; Motor evoked potential; Spinal fluid pressures; MAP; COPD; spinal cord injury; aneurysm; delayed
• ISSN: 1043-0679; 1532-9488
• DOI: 10.1053/j.semtcvs.2017.05.007

Abstract Objective Delayed paraplegia (DP) following thoracoabdominal aortic repair is a dreaded complication. We reviewed our experience with the occurrence and management of DP using our previously described COPS protocol. Methods Complete documentation of hourly spinal fluid pressures (SP) and detailed hemodynamic variables have been available in the medical record system since 2000. A case control design was utilized to analyze the extensive hourly data in the perioperative period. Controls were sampled randomly using a computerized sampling protocol. Data were analyzed by contingency table, t test and regression analysis, as appropriate. Results Between 2000 and 2011, we performed 1,059 thoracoabdominal or descending thoracic aortic repairs. Of these, 47 (4.4%) had DP and 31 (2.9%) had immediate neurologic deficit. Baseline and intraoperative variables were not significantly or independently predictive, other than loss of motor evoked potentials (OR 8.6, p=0.007). Postoperatively, renal replacement therapy (OR 7.5, p=0.035) and drain complications (OR 21.4, p<.001) were significantly associated with DP. Variation in systolic blood pressure (SBP) was also highly predictive and demonstrated a monotonic increase with greater variability each day closer to DP onset (OR 1.2, p=0.014). Similarly, spinal cord perfusion pressure (SCPP=SBP-SP) showed increased risk with greater variability closer to event day (OR 1.3, p=0.009). Fluctuation of more than 15 mmHg in systolic blood pressure in a 24-hour period was associated with 3.2-fold increased odds of DP (p=0.004). In all, 8/47 (17%) made a full recovery, while 19 (40%) had partial recovery by discharge. The 30-day mortality was 18/47 (38%) in DP and 7/55 (13%) in controls (p<0.001). Long-term survival was significantly lower among DP cases (5-year survival of 28% vs.75%, p<0.001). Conclusions DP occurs infrequently and is predictably associated with intraoperative loss of MEP, postoperative renal replacement therapy, drain complications and unstable systolic and spinal cord perfusion pressures. Increased vigilance is recommended for patients who experience any of these events. Recovery occurred in more than half the patients with the use of COPS protocol (blood pressure stabilization, cerebrospinal fluid draining and O2 delivery).