Pdf Anesthetic Considerations For Carotid Endarterectomy Cpt

Preoperative Evaluation and Questions: How many and which vessels? Grafts from where? Is the surgeon planning to use radial artery for a graft? LV function? Valve disease?

Since its introduction in the 1950s, carotid endarterectomy (CEA) has been considered the gold standard treatment option for carotid revascularization. However, in patients with high-risk anatomic and/or physiologic characteristics, CEA is associated with higher rates of adverse outcomes. In our previous Cochrane review of several small, randomized control trials (RCT) of carotid endarterectomy using local anesthesia (LA) vs general anesthesia published during 1966 to 2007, there was a trend toward lower operative mortality with LA and no difference in risk of stroke, 2,3 but statistical power was limited.

Is the patient High Risk? High Risk = EF <40%, LVEDP >18, CI <2.
Baseline neurologic status? Renal function?
Is there an indication for TEE? (high risk pt? co-existing valve disease?).

Risk: Mortality 2-4%; Morbidity: Cognitive decline post-op in Pts >60yo = 26%, CVA 2-4%, MI 3-6%. [Jaffe RA and Samuels, SI. Anesthesiologist’s Manual of Surgical Procedures, 4th ed.]

Induction: Appropriate induction of anesthesia for cardiac surgery is critical unique. By definition these patients have areas of myocardium that are at-risk or already ischemic. Traditional “Cardiac” induction consists of high dose narcotics, usually Fentanyl 10-100mcg/kg, Sufentanil 2-20mcg/kg, or Morphine 1-5mg/kg. Sufentanil has been associated with faster induction and recovery than Fentanyl or Morphine [Sanford TJ Anesth Analg. 1986 Mar;65(3):259 PMID: 2937352]. However, a recent study reported Morphine resulted in better quality of recovery and post-op pain control than Fentanyl [Murphy GS Anesth Analg 2009; 109:311]

Lines and Monitors: Arterial line should be placed prior to induction. Right IJ MAC can be placed pre or post induction. Pulmonary Artery Catheter placement is common for nearly all cardiac surgeries. There is debate about whether PAC use is beneficial [Sandham JD N Engl J Med 2003 Jan 2;348(1):5]. However, many cardiac surgeons and anesthesiologist are accustomed to the information provided by the PAC and use this info to guide treatment intra-op and post-op.

Intraoperative Goals and Events:

Opioids as primary induction agent to preserve hemodynamics. Need a hypnotic to ensure lack of consciousness and amnesia (Midaz or Sevo most common). Maintain Cerebral/Coronary Perfusion Pressure and Oxygenation. If planning “fast track” use lower dose Fentanyl (10-15mcg/kg).
Pre-CPB: Blood in room for Sternotomy, (especially if Redo), Lungs down, Internal Defibrilator connected, Pacer box available and functioning.
CPB: Heparin (given by Perfusionist), ACT >350, Mean BP managed by Perfusionist, PAC pulled back 5cm, empty foley to get accurate “on-pump” urine out-put, watch aortic cannula for air.
Post-CPB: Checklist = Hemodynamics (rhythm, BP), Ventilation (start when pulsatile PA tracing), Ca++, Acid/Base, Hb, Temp (>36), K+.

Surgical Course
Line placement (a-line, PAC) w/ sedation pre-op. Induction, Baseline ABG/ACT, Graft harvest, Sternotomy (lungs down, have blood available), CBP access established (MAP <70 prior to Aortic cannulation to reduce chance of dissection), Start CPB (Stop ventilation, KVO all gtts, “reto” connected to PA transducer), Cooling to ~26, Graft anastomosis, Rewarming (more Midaz/Panc with rewarming), Wean from CPB (Pressors PRN), TEE to eval EF/Wall motion.

EBL: 500-1000ml

Duration: 3-4 hrs

Pain: 7-8/10

Post-Operative Concerns, Transport, Disposition: To ICU intubated. If “fast track” then plan for extubation 6-8hrs post-op. Potential for recall.
Graft survival: Vein grafts = 50% significant stenosis at 10yrs, Internal Mammillary = 90% patent at 10yrs. Gomez peer alikes.

Evidence-Based Medicine:
Preconditioning: The cardio-protective effect of volatile anesthetics has received much attention in recent years. There is certainly experimental evidence showing post-ischemic protection and suggested mechanisms. [Zaugg M Anesthesiology 2002; 97:4-14]. The most recent review article on this topic indicated that, although there is experimental and clinical data supporting cardioprotective effects of volatile anesthetics, there is still no evidence of an improvement in morbidity or mortality [De Hert SG Anesth Analg 2005; 100:1584-1593]. One interesting question to ask is, if current practice is to use Volatiles for cardiac surgery will an improvement in M & M change our practice? Likely not. However, the trend toward “fast-track” and even “ultra fast-track” cardiac surgery may eventually lead to a change in the standard use of volatile anesthetics in favor of TIVA. There is one recent study that compared Volatiles to TIVA for CABG. There was a difference in hospital length of stay (12 days for the TIVA group, 9 days for the SEVO group and 9 days for the DES group.) and 1 year mortality (12.3% in the TIVA group, 3.3% in the sevoflurane group, and 6.7% in the desflurane group), but the group assignment (TIVA, Sevo, Des) was not a significant independent predictor of 1 year mortality. [De Hert SG Anaesthesia 2009; 64: p953–960] Again, this only matters if we think TIVA is the future of anesthesia for cardiac surgery, which it may not be.

Whipple

Preoperative Evaluation and Questions: 5-year survival rate is 15% – 25% (versus 1% – 5% with no cancer-directed treatment) [Marandola M et al. Transplantation Proceedings 40: 1195, 2008]. Electrolyte abnormalities are common in patients with abdominal pain or vomiting, thus consider a preoperative chem-7. Blood products available + Ranger / rapid infuser.

Risk: operative mortality is less than 5% in centers that perform > five cases per year. Systemic (non-operative) complications cause the majority of perioperative deaths [Marandola M et al. Transplantation Proceedings 40: 1195, 2008] – the most common causes of death are sepsis, hemorrhage, and cardiovascular events [Schwartz’s Principles of Surgery, 8th ed. Chapter 32: Pancreas. McGraw-Hill, 2004]

Induction/Airway: if the tumor is obstructive, consider RSI.

Lines and Monitors: two large-bore IVs, arterial line (frequent labs, esp. glucose), +/- central line.

Preoperative Meds:cefoxitin (do not give SQ heparin (5000 U) until AFTER the epidural, if placed).

Mode of anesthesia: general +/- epidural (T6-8, inferior angle of scapula is approximately T7), although exclusively epidural anesthesia has been performed on at least 15 patients [Nakashima H et al. Int Surg 80: 125, 1995]. If an opiate-enhanced epidural is used, consider a lipophilic drug (ex. fentanyl), as morphine will potentially spread rostrally, potentially causing mental status changes and respiratory depression. Consider 0.5% bupivacaine intraoperatively, followed by 0.125% – 0.25% post-operatively. If blood loss is a major concern, consider holding local anesthetics until towards the end of surgery. In patients for whom an epidural is not possible, consider ketamine at 0.2 mg/kg/hr after a 0.5 mg/kg bolus, as well as gabapentin 600-1200 mg PO.

Positioning: supine

Surgical Course: laparotomy to gain access to the peritoneum, followed by a determination of resectability (an over-involved or highly metastatic tumor will not be resected). If the tumor is resectable, the head of the pancreas is mobilized (“Kocher maneuver” is performed, dissecting behind the head of the pancreas), the common bile duct is transected and the gall bladder removed, vascular structures (ex. SMV) are freed, and then the pancreas, proximal duodenum / distal stomach, and jejunum (distal to the ligament of Treitz) are incised, and the entire specimen subsequently removed. Drains are almost always placed in organ bed. According to Schwartz, “Traditionally, most surgeons place drains around the pancreatic and biliary anastomoses because the most dreaded complication of pancreaticoduodenectomy, disruption of the pancreaticojejunostomy, cannot be avoided in 1 out of 10 patients. This complication can lead to the development of an upper abdominal abscess or can present as an external pancreatic fistula. Usually a pure pancreatic leak is controlled by the drains and will eventually seal spontaneously… some recent studies have questioned the practice of routine drain placement after pancreaticoduodenectomy. These studies [Heslin MJ et al. J Gastrointest Surg 2: 373, 1998] indicated that most pancreatic leaks can be managed with percutaneous drainage” [Schwartz’s Principles of Surgery, 8th ed. Chapter 32: Pancreas. McGraw-Hill, 2004]

Intraoperative Goals and Events: placement of nasogastric tube (will be used post-operatively). WARM maintenance fluids at 6-10 cc/kg/hr.

EBL: 500-750 cc

Duration: 4-5 hours

Emergence: depends on fluid shifts and cardiopulmonary status. May remain intubated.

Pain: 8/10

Post-Operative Concerns, Transport, Disposition: ICU or epidural-trained ward if epidural in place.

Other:

Evidence-Based Medicine:

Octreotride (3 x 100 ucg/day, SC) may reduce post-operative complications [Fiess H et al. Digestion 55 S1: 35, 1994]. There does not appear to be a difference between octreotide and somatostatin [Closset J et al. Hepatogastroenterology 55: 1818, 2008]

An exhaustive review of intraoperative radiotherapy (IORT) stated that IORT “may have an important palliative role in patients with unresectable pancreatic cancers, ameliorating visceral pain and promoting local control of the primary tumor; however, IORT appears to have no significant effect on overall survival” [Sindelar WF and Kinsella TJ. Ann Oncol 10S: S226, 1999]