Michael J. Brown

Cardiac Risk of Noncardiac Surgery after Percutaneous Coronary Intervention with Drug-eluting Stents

Background:The American College of Cardiology released a scientific advisory that included a recommendation to delay elective of noncardiac surgery (NCS) for 1 yr after percutaneous coronary intervention (PCI) with a drug-eluting stent (DES). Methods:This single-center, retrospective study examined the risk for complications of NCS performed within 2 yr after DES placement and examined whether this risk changed based on the time between procedures. The primary endpoint was major adverse cardiac events (MACEs) during the hospitalization for NCS. Bleeding events were analyzed as a secondary endpoint. Results:From April 22, 2003, to December 31, 2006, a total of 520 patients underwent NCS within 2 yr after PCI with a DES at Mayo Clinic. The majority, 84%, of the DES placed were Cypher stents. The frequency of MACE was not found to be significantly associated with the time between PCI and NCS (rate of MACEs 6.4, 5.7, 5.9, and 3.3% at 0–90, 91–180, 181–365, and 366–730 days after PCI with DES, respectively; P = 0.727 for comparison across groups). Characteristics found to be associated with MACEs in univariate analysis were advanced age (P = 0.031), emergent NCS (P = 0.006), shock at time of PCI (P = 0.035), previous history of myocardial infarction (P = 0.046), and continuation of a thienopyridine (ticlopidine or clopidogrel) into the preoperative period (P = 0.040). The rate of transfusion did not seem to be associated with antiplatelet therapy use. Conclusions:The risk of MACEs with NCS after DES placement was not significantly associated with time from stenting to surgery, but observed rates of MACEs were lowest after 1 yr.

Use of Lean and Six Sigma Methodology to Improve Operating Room Efficiency in a High-Volume Tertiary-Care Academic Medical Center

BACKGROUND Operating rooms (ORs) are resource-intense and costly hospital units. Maximizing OR efficiency is essential to maintaining an economically viable institution. OR efficiency projects often focus on a limited number of ORs or cases. Efforts across an entire OR suite have not been reported. Lean and Six Sigma methodologies were developed in the manufacturing industry to increase efficiency by eliminating non-value-added steps. We applied Lean and Six Sigma methodologies across an entire surgical suite to improve efficiency. STUDY DESIGN A multidisciplinary surgical process improvement team constructed a value stream map of the entire surgical process from the decision for surgery to discharge. Each process step was analyzed in 3 domains, ie, personnel, information processed, and time. Multidisciplinary teams addressed 5 work streams to increase value at each step: minimizing volume variation; streamlining the preoperative process; reducing nonoperative time; eliminating redundant information; and promoting employee engagement. Process improvements were implemented sequentially in surgical specialties. Key performance metrics were collected before and after implementation. RESULTS Across 3 surgical specialties, process redesign resulted in substantial improvements in on-time starts and reduction in number of cases past 5 pm. Substantial gains were achieved in nonoperative time, staff overtime, and ORs saved. These changes resulted in substantial increases in margin/OR/day. CONCLUSIONS Use of Lean and Six Sigma methodologies increased OR efficiency and financial performance across an entire operating suite. Process mapping, leadership support, staff engagement, and sharing performance metrics are keys to enhancing OR efficiency. The performance gains were substantial, sustainable, positive financially, and transferrable to other specialties.

Time and cardiac risk of surgery after bare-metal stent percutaneous coronary intervention

Background:The duration of time that elective noncardiac surgery (NCS) should be delayed after percutaneous coronary intervention (PCI) with bare metal stents (BMSs) is unknown. Methods:This large, single-center, retrospective study examined the relation between complication rate in patients with BMSs undergoing NCS and the duration of time between PCI and NCS. Primary endpoints included in-hospital major adverse cardiac events (death, myocardial infarction, stent thrombosis, or repeat revascularization with either coronary artery bypass grafting or PCI of the target vessel) and bleeding events. The relation between the events and the timing of noncardiac surgery after PCI with BMS was assessed using univariate analysis and multiple logistic regression. Results:From January 1, 1990, to January 1, 2005, a total of 899 patients were identified. The frequency of major adverse cardiac events was 10.5% when NCS was performed less than 30 days after PCI with BMS, 3.8% when NCS was performed between 31 and 90 days after PCI with BMS, and 2.8% when NCS was performed more than 90 days after PCI with BMS. In univariate and multivariate analyses, a shorter time interval between PCI with BMS and noncardiac surgery was significantly associated with increased incidence of major adverse cardiac events (univariate: P < 0.001; odds ratio = 4.0; 95% confidence interval, 2.0–8.3; multivariate: P = 0.006; odds ratio = 3.2; 95% confidence interval, 1.5–6.9). Bleeding events were not associated with time between PCI with BMS and NCS or with the use of antiplatelet therapy in the week before NCS. Conclusions:The incidence of major adverse cardiac events is lowest when NCS is performed at least 90 days after PCI with BMS.

Complications After Unintentional Intra-arterial Injection of Drugs: Risks, Outcomes, and Management Strategies

Unintentional intra-arterial injection of medication, either iatrogenic or self-administered, is a source of considerable morbidity. Normal vascular anatomical proximity, aberrant vasculature, procedurally difficult situations, and medical personnel error all contribute to unintentional cannulation of arteries in an attempt to achieve intravenous access. Delivery of certain medications via arterial access has led to clinically important sequelae, including paresthesias, severe pain, motor dysfunction, compartment syndrome, gangrene, and limb loss. We comprehensively review the current literature, highlighting available information on risk factors, symptoms, pathogenesis, sequelae, and management strategies for unintentional intra-arterial injection. We believe that all physicians and ancillary personnel who administer Intravenous therapies should be aware of this serious problem.

Preoperative Gabapentin for Acute Post-thoracotomy Analgesia: A Randomized, Double-Blinded, Active Placebo-Controlled Study

Background:  The role of preoperative gabapentin in postoperative pain management is not clear, particularly in patients receiving regional blockade. Patients undergoing thoracotomy benefit from epidural analgesia but still may experience significant postoperative pain. We examined the effect of preoperative gabapentin in thoracotomy patients.

Hypertensive Crisis in a Patient Undergoing Percutaneous Radiofrequency Ablation of an Adrenal Mass Under General Anesthesia

Radiofrequency ablation (RFA) is an effective therapeutic intervention for a variety of neoplastic lesions. Many of these procedures are conducted with patients under general anesthesia. Although RFA is associated with infrequent complications, it is not without risk. Injury to adjacent normal structures is a major concern during RFA of cancerous lesions. Unintended injury to normal adrenal tissue during RFA of adrenal tumors can lead to hypertensive crisis, a potentially catastrophic complication. Hemodynamic consequences of RFA of primary or metastatic adrenal masses have not been reported. We report a case of hypertensive crisis (249/140 mm Hg), tachycardia, and ventricular arrhythmia in an 82-yr-old woman undergoing RFA of renal cell carcinoma metastatic to the adrenal gland. Anesthesiologists should be aware of this potentially catastrophic complication. Direct-acting vasodilators and short-acting &bgr;1-adrenergic antagonists should be immediately available, and intraarterial blood pressure monitoring should be seriously considered when providing care for patients undergoing RFA of an adrenal mass.

Motor Evoked Potential Monitoring during Cryoablation of Musculoskeletal Tumors

PURPOSE To describe the use of intraprocedural motor evoked potential (MEP) monitoring to minimize risk of neural injury during percutaneous cryoablation of perineural musculoskeletal tumors. MATERIALS AND METHODS A single-institution retrospective review of cryoablation procedures performed to treat perineural musculoskeletal tumors with the use of MEP monitoring between May 2011 and March 2013 yielded 59 procedures to treat 64 tumors in 52 patients (26 male). Median age was 61 years (range, 4-82 y). Tumors were located in the spine (n = 27), sacrum (n = 3), retroperitoneum (n = 4), pelvis (n = 22), and extremities (n = 8), and 21 different tumor histologies were represented. Median tumor size was 4.0 cm (range, 0.8-15.0 cm). Total intravenous general anesthesia, computed tomographic guidance, and transcranial MEP monitoring were employed. Patient demographics, tumor characteristics, MEP findings, and clinical outcomes were assessed. RESULTS Nineteen of 59 procedures (32%) resulted in decreases in intraprocedural MEPs, including 15 (25%) with transient decreases and four (7%) with persistent decreases. Two of the four patients with persistent MEP decreases (50%) had motor deficits following ablation. No functional motor deficit developed in a patient with transient MEP decreases or no MEP change. The risk of major motor injury with persistent MEP changes was significantly increased versus transient or no MEP change (P = .0045; relative risk, 69.8; 95% confidence interval, 5.9 to > 100). MEP decreases were 100% sensitive and 70% specific for the detection of motor deficits. CONCLUSIONS Persistent MEP decreases correlate with postprocedural sustained motor deficits. Intraprocedural MEP monitoring helps predict neural injury and may improve patient safety during cryoablation of perineural musculoskeletal tumors.

Safety of Overlapping Surgery at a High-volume Referral Center

Objective: To compare safety profiles of overlapping and nonoverlapping surgical procedures at a large tertiary-referral center where overlapping surgery is performed. Background: Surgical procedures are frequently performed as overlapping, wherein one surgeon is responsible for 2 procedures occurring at the same time, but critical portions are not coincident. The safety of this practice has not been characterized. Methods: Primary analyses included elective, adult, inpatient surgical procedures from January 2013 to September 2015 available through University HealthSystem Consortium. Overlapping and nonoverlapping procedures were matched in an unbalanced manner (m:n) by procedure type. Confirmatory analyses from the American College of Surgeons-National Surgical Quality Improvement Program investigated elective surgical procedures from January 2011 to December 2014. We compared outcomes mortality and length of stay after adjustment for registry-predicted risk, case-mix, and surgeon using mixed models. Results: The University HealthSystem Consortium sample included 10,765 overlapping cases, of which 10,614 (98.6%) were matched to 16,111 nonoverlapping procedures. Adjusted odds ratio for inpatient mortality was greater for nonoverlapping procedures (adjusted odds ratio, OR = 2.14 vs overlapping procedures; 95% confidence interval, CI 1.23–3.73; P = 0.007) and length of stay was no different (+1% for nonoverlapping cases; 95% CI, −1% to +2%; P = 0.50). In confirmatory analyses, 93.7% (3712/3961) of overlapping procedures matched to 5,637 nonoverlapping procedures. The 30-day mortality (adjusted OR = 0.69 nonoverlapping vs overlapping procedures; 95% CI, 0.13–3.57; P = 0.65), morbidity (adjusted OR = 1.11; 95% CI, 0.92–1.35; P = 0.27) and length of stay (−4% for nonoverlapping; 95% CI, −4% to −3%; P < 0.001) were not clinically different. Conclusions: These findings from administrative and clinical registries support the safety of overlapping surgical procedures at this center but may not extrapolate to other centers.

Bridging with glycoprotein IIb/IIIa inhibitors for periprocedural management of antiplatelet therapy in patients with drug eluting stents†

Objective: To describe outcomes when glycoprotein IIb/IIIa (GP IIb/IIIa) inhibitors are used as bridging antiplatelet therapy for surgical procedures in patients with drug eluting stents (DES). Background: The optimal management of patients with DES who require surgical procedures prior to completion of antiplatelet therapy is unclear. In high risk patients, the use of GP IIb/IIIa inhibitors as bridging therapy while antiplatelet therapy is held has been described, but safety and efficacy data remain sparse. Methods: A pharmacy database was used to identify GP IIb/IIIa inhibitor orders at our hospital between January 1, 2007 and July 31, 2009. Indication for GP IIb/IIIa inhibitor administration and other clinical data were gathered through retrospective review of medical records. End points assessed were stent thrombosis, major bleeding, minor bleeding, postoperative acute coronary syndrome, and death within 30 days. Results: Four thousand One hundred seventy‐six separate orders for GP IIb/IIIa inhibitors were identified (January 1, 2007 to July 31, 2009). Six patients underwent non‐cardiac and thirteen underwent cardiac surgery. Clopidogrel was discontinued a median of 6 days before surgery and 2 days prior to initiating GP IIb/IIIa inhibitor. All bridging patients were treated with eptifibatide infusion prior to procedure. There were no stent thromboses, deaths, or acute coronary syndrome events. Major bleeding occurred in 7 (53.9%) cardiac surgery patients and none of the non‐cardiac surgery patients, while minor bleeding occurred in 1 (7.7%) and 1 (16.6%) patients, respectively. Conclusions: In patients with DES, who require cessation of clopidogrel before surgery, bridging with GP IIb/IIIa inhibitors appears effective in preventing adverse cardiac outcomes but may be associated with bleeding in patients undergoing cardiac surgery.

Perioperative Statin Therapy and Renal Outcomes After Major Vascular Surgery: A Propensity-Based Analysis

OBJECTIVE To evaluate how the presence and timing of statin therapy affect perioperative renal outcomes after major vascular surgery. DESIGN Retrospective cohort study. SETTING Surgical intensive care unit at a single academic medical center. PARTICIPANTS Patients undergoing major vascular surgery between July 2004 and October 2005. MEASUREMENTS AND MAIN RESULTS The presence and timing of perioperative statin administration and the propensity for receiving such therapy were noted. Renal outcomes, lengths of stay, and mortality were reviewed. One hundred fifty-one procedures were performed. Eighty-nine patients (59%) received statin therapy. There was no evidence for renal protection with perioperative statin therapy (Delta creatinine 0.2 mg/dL v 0.2 mg/dL, p = 0.41; acute renal injury/acute renal failure 8% v 6%, p = 1.00; renal replacement therapy 3% v 3%, p = 1.00; all statin v no statin, respectively). With the possible exception of early reinstitution of statin therapy in chronic statin users, subgroup analyses failed to confirm an association between statin timing and prevention of postoperative renal dysfunction. CONCLUSIONS In the present investigation, neither the presence nor timing of perioperative statin therapy was associated with improved renal outcomes in patients undergoing a range of major vascular procedures. A possible exception is early postoperative reinitiation of statin therapy in chronic statin users. The discrepant results of available literature preclude a definitive statement on the use of statin therapy as a means of preventing postoperative renal dysfunction. An adequately powered prospective trial is needed before advocating the routine use of statin therapy for perioperative renal protection.