Ultrasound-guided erector spinae plane blocks for pain management after open lumbar laminectomy

PURPOSE

Lumbar spine surgery is associated with significant postoperative pain. The benefits of erector spinae plane blocks (ESPBs) combined with multimodal analgesia has not been adequately studied. We evaluated the analgesic effects of bilateral ESPBs as a component of multimodal analgesia after open lumbar laminectomy.

METHODS

Analgesic effects of preoperative, bilateral, ultrasound-guided ESPBs combined with standardized multimodal analgesia (n = 25) was compared with multimodal analgesia alone (n = 25) in patients undergoing one or two level open lumbar laminectomy. Other aspects of perioperative care were similar. The primary outcome measure was cumulative opioid consumption at 24 h. Secondary outcomes included opioid consumption, pain scores, and nausea and vomiting requiring antiemetics on arrival to the post-anesthesia care unit (PACU), at 24 h, 48 h, and 72 h after surgery, as well as duration of the PACU and hospital stay.

RESULTS

Opioid requirements at 24 h were significantly lower with ESPBs (31.9 ± 12.3 mg vs. 61.2 ± 29.9 mg, oral morphine equivalents). Pain scores were significantly lower with ESPBs in the PACU and through postoperative day two. Patients who received ESPBs required fewer postoperative antiemetic therapy (n = 3, 12%) compared to those without ESPBs (n = 12, 48%). Furthermore, PACU duration was significantly shorter with ESPBs (49.7 ± 9.5 vs. 79.9 ± 24.6 min).

CONCLUSIONS

Ultrasound-guided, bilateral ESPBs, when added to an optimal multimodal analgesia technique, reduce opioid consumption and pain scores, the need for antiemetic therapy, and the duration of stay in the PACU after one or two level open lumbar laminectomy.

Comparison of Erector Spinae Plane Blocks Versus Multimodal Pain Management for Traumatic Rib Fractures: A Matched Cohort Study

INTRODUCTION

Erector spinae plane blocks (ESPBs) are frequently utilized when treating patients with multiple rib fractures. While previous work has demonstrated the efficacy of ESPB as an adequate method of pain control, there has been no work comparing a continuous ESPB to "best practice" multimodal pain control. We hypothesize that a continuous ESPB catheter combined with a multimodal pain regimen may be associated with a decrease in opioid requirements when compared to a multimodal pain regimen alone.

METHODS

This was a retrospective observational cohort study at a level 1 trauma center from September 2016 through September 2021. Inclusion criteria included patients 18 y or older with at least three unilateral rib fractures who were not mechanically ventilated during admission. The primary outcome was the total morphine equivalents utilized throughout the index admission.

RESULTS

A total of 142 patients were included in this study, 71 in each cohort. Patients included had a mean age of 52.5 y, and 18% were female. Demographic data including injury severity score, total number of rib fractures, and length of stay were similar. While there was a trend toward a decrease in morphine equivalents in the patient cohort undergoing ESPB catheter placement, this was not found to be statistically significant (284.3 ± 244.8 versus 412.6 ± 622.2, P = 0.5).

CONCLUSIONS

While ESPB catheters are frequently utilized for analgesia in the setting of multiple rib fractures, there was no decrease in total opioid usage when compared with patients who were managed with a multimodal pain regimen alone. Further assessment comparing ESPB catheters to best practice multimodal pain control regimens through a prospective, multicenter trial is required to further validate these findings.

Pain Management After Open Liver Resection: Epidural Analgesia Versus Ultrasound-Guided Erector Spinae Plane Block

Background: Multimodal analgesia techniques, including regional analgesia, have been shown to provide effective analgesia and minimize opioid consumption after liver resection surgery. While thoracic epidural analgesia (TEA) is considered the gold standard, its role in the current era of enhanced recovery after surgery (ERAS) has been questioned. Erector spinae plane blocks (ESPBs) have the potential to provide effective postoperative analgesia without the risks associated with epidural analgesia. The primary aim of this quality improvement project was to evaluate the analgesic efficacy of ultrasound-guided ESPB in comparison with TEA in patients undergoing open liver resection.

Methods: Fifty patients who underwent open liver resection and received TEA (n=25) or ESPB (n=25) as part of an ERAS pathway were retrospectively identified. The primary outcome measure was cumulative postoperative opioid consumption at 24 hours. Secondary outcomes included opioid consumption, pain scores, the incidence of nausea and vomiting requiring antiemetics, lower extremity muscle weakness, and occurrence of hypotension requiring treatment on arrival to the post-anesthesia care unit and at 2, 6, 12, 24 hours, and daily through postoperative day 7. 

Results: Opioid requirements were significantly lower in the TEA group compared to the ESPB group. Postoperative pain scores at rest and with deep inspiration were significantly lower in the TEA group through postoperative day 5. There were no differences in other outcome measures.

Conclusions: These findings suggest that compared with ESPB, TEA provides superior pain relief after open liver resection.

Erector spinae plane block versus thoracic paravertebral block for pain management after total bilateral mastectomies

This prospectively designed, clinical quality improvement project compared pain scores and opioid consumption between ultrasound-guided, erector spinae plane blocks (ESPB) and thoracic paravertebral blocks (PVB) in patients undergoing total bilateral mastectomies without reconstruction. Twenty-five patients were included in an enhanced recovery pathway and received an ESPB on one side and a PVB on the contralateral side. Numeric rating scores at rest and with movement for each side were recorded in the recovery room at 2, 6, 12, 24, and 48 hours and on days 3 to 7. There were no significant differences in the resting or movement-evoked pain scores between sides receiving ESPB or PVB at any time point up to day 7 after surgery. Both ESPB and PVB confer equal analgesic effects in patients undergoing mastectomies. ESPB provides an alternative to PVB in reducing postoperative pain in patients undergoing mastectomy as part of an enhanced recovery pathway.

Comparison of Regional Anesthesia Timing on Pain, Opioid Use, and Postanesthesia Care Unit Length of Stay in Patients Undergoing Open Reduction and Internal Fixation of Ankle Fractures

Regional nerve blocks are an effective method of managing acute pain associated with surgery. The relative benefit of preoperative versus postoperative peripheral nerve blocks is not entirely clear. The primary aim of this study was to determine differences in pain scores in patients undergoing preoperative block versus postoperative block versus no block. We hypothesized that patients receiving preoperative blocks would have reduced pain scores and decreased opioid use in the immediate postoperative period. We conducted a retrospective cohort analysis of 302 consecutive patients undergoing unilateral open reduction and internal fixation of ankle fracture under general anesthesia. We identified 3 groups: preoperative block, postoperative block, or no block. Data obtained from our electronic medical records included demographic information, postanesthesia care unit length of stay, pain scores obtained preoperatively, upon arrival to the postanesthesia care unit, and upon discharge from the postanesthesia care unit as well as intraoperative and postanesthesia care unit opioid utilization. Patients receiving preoperative block had significantly lower pain scores, less intraoperative or postanesthesia care unit opioid use, and shorter postanesthesia care unit dwell time compared with patients receiving postoperative block or no block. Preoperative popliteal sciatic and adductor canal blocks in patients undergoing ankle fracture surgery appears to be more effective than either postoperative block or no block.

Safety of Erector Spinae Plane Blocks in Patients With Chest Wall Trauma on Venous Thromboembolism Prophylaxis

BACKGROUND

Current guidelines for severe rib fractures recommend neuraxial blockade in addition to multimodal pain therapies. While the guidelines for venous thromboembolism prevention recommend chemoprophylaxis, these medications must be held for neuraxial blockade placement. Erector spinae plane block (ESPB) is a newly described block for thoracic pain control. Advantages include its quick learning curve and potential for less bleeding complications. We describe the use of ESPB for rib fractures in patients on chemoprophylaxis. We hypothesize that ESPB can be performed in this patient population without holding chemoprophylaxis.

MATERIALS AND METHODS

This was a retrospective observational cohort study of a level 1 trauma center from 9/2016 to 12/2018. All patients with trauma with rib fractures undergoing neuraxial blockade or ESPB were included. Demographics, chemoprophylaxis and anticoagulation regimens, outcomes, and complications were collected.

RESULTS

Nine hundred sixty-four patients with rib fracture(s) were admitted. Of these, 73 had a pain management consult. Thirteen had epidural catheters and 25 had ESPBs placed. There was no difference in demographics, injury patterns, bleeding complications, or venous thromboembolism rates among the groups. Patients with ESPB were less likely to have a dose of chemoprophylaxis held because of placement of a catheter (25% versus 100%, P < 0.00001). Three patients with ESPB were on oral anticoagulation on admission, and two were able to continue their regimen during placement.

CONCLUSIONS

ESPB can be safely placed in patients on chemoprophylaxis. It should be considered over traditional blocks in patients with blunt chest wall trauma because of its technical ease and ability to be performed with chemoprophylaxis.

Evaluation of Opioid Prescribing Habits Based on Analysis of a State Prescription Drug Monitoring Program

Background: The current opioid epidemic is perhaps the greatest public health crisis in the United States. Although multiple factors led to the rise of this epidemic, it is without question associated with the rise in opioid prescribing. Objectives: Better understanding of the opioid prescribing may provide insights into populationlevel trends contributing to this epidemic, and opportunities to decrease the magnitude of opioid overdose-related death. Therefore we assessed trends in opioid prescribing habits based on analysis of the Texas Prescription Drug Monitoring Program (PDMP) and geographic, ethnic, and incomerelated data from the US Census Bureau. Study Design: Multiple linear regression analysis of Texas PDMP and US Census Bureau data were performed to assess for correlations to opioid prescribing based on geographic, ethnic, income, and time-related variables. Setting: All controlled substances prescribed in the state of Texas from April 2015 to May 2018 were analyzed. Methods: We obtained data from the Texas PDMP for all controlled substances from April 2015 to May 2018. We performed multiple linear regression analysis of these data along with US Census Bureau data to assess for correlations based on geographic, ethnic, income, and time-related variables. We hypothesized that there would be substantial variability in opioid prescribing habits based on geographic, ethnic, and economic variables. Results: Approximately 200 million pills of controlled substances were prescribed per month over the studied time frame. Overall, high geographic variability was noted, and this strongly correlated to race and ethnicity. Opioid prescribing increased along with the proportion of white residents within a county, but a similar negative correlation was noted with increasing Hispanic population proportion. This correlation was noted throughout the study period, but up until 2017, lower income levels among higher white population had even higher correlation with increased opioid prescribing. Cumulative opioid prescriptions throughout the state fell beginning in 2017. Limitations: This analysis does not include opioids obtained illicitly or from prescriptions outside the state of Texas. The specificity of geographic data are limited to the county level due to irregular entry of zip code data by prescribing pharmacies. Conclusions: In the state of Texas over the studied time period, there was strong correlation for higher rates of opioid prescribing as white population increased despite overall decreased opioid prescribing starting in 2017. Until 2017, this correlation grew stronger as low-income white population increased. Key words: Opioid, opioid epidemic, opioid utilization

Evaluation of Opioid Prescribing Habits Based on Analysis of a State Prescription Drug Monitoring Program

BACKGROUND

The current opioid epidemic is perhaps the greatest public health crisis in the United States. Although multiple factors led to the rise of this epidemic, it is without question associated with the rise in opioid prescribing.

OBJECTIVES

Better understanding of the opioid prescribing may provide insights into population-level trends contributing to this epidemic, and opportunities to decrease the magnitude of opioid overdose-related death. Therefore we assessed trends in opioid prescribing habits based on analysis of the Texas Prescription Drug Monitoring Program (PDMP) and geographic, ethnic, and income-related data from the US Census Bureau.

STUDY DESIGN

Multiple linear regression analysis of Texas PDMP and US Census Bureau data were performed to assess for correlations to opioid prescribing based on geographic, ethnic, income, and time-related variables.

SETTING

All controlled substances prescribed in the state of Texas from April 2015 to May 2018 were analyzed.

METHODS

We obtained data from the Texas PDMP for all controlled substances from April 2015 to May 2018. We performed multiple linear regression analysis of these data along with US Census Bureau data to assess for correlations based on geographic, ethnic, income, and time-related variables. We hypothesized that there would be substantial variability in opioid prescribing habits based on geographic, ethnic, and economic variables.

RESULTS

Approximately 200 million pills of controlled substances were prescribed per month over the studied time frame. Overall, high geographic variability was noted, and this strongly correlated to race and ethnicity. Opioid prescribing increased along with the proportion of white residents within a county, but a similar negative correlation was noted with increasing Hispanic population proportion. This correlation was noted throughout the study period, but up until 2017, lower income levels among higher white population had even higher correlation with increased opioid prescribing. Cumulative opioid prescriptions throughout the state fell beginning in 2017.

LIMITATIONS

This analysis does not include opioids obtained illicitly or from prescriptions outside the state of Texas. The specificity of geographic data are limited to the county level due to irregular entry of zip code data by prescribing pharmacies.

CONCLUSIONS

In the state of Texas over the studied time period, there was strong correlation for higher rates of opioid prescribing as white population increased despite overall decreased opioid prescribing starting in 2017. Until 2017, this correlation grew stronger as low-income white population increased.

KEY WORDS

Opioid, opioid epidemic, opioid utilization.

A review of the anesthetic implications of marijuana use

Marijuana, derived from plants of the genus Cannabis, is the most commonly used illicit drug in the United States. Marijuana is illegal at the federal level and remains a Drug Enforcement Agency Schedule 1 substance. Nevertheless, most states have passed less stringent legislation related to its use, ranging from decriminalization of possession to allowing medical or even recreational use, and some county and municipal law enforcement agencies have refrained from prosecuting personal possession and/or use even when statute would require such action. Therefore, as use of marijuana becomes more common in the larger population, more patients who are chronic and/or heavy users of marijuana present for surgical procedures, raising the question of best practices to care for these patients in the perioperative period. This review summarizes the known physiologic effects of marijuana in humans, discusses potential implications of marijuana use that the anesthesiologist should consider at each phase of the perioperative period, and outlines recommendations for future study.

Ultrasound-guided suprainguinal fascia iliaca compartment block versus periarticular infiltration for pain management after total hip arthroplasty: a randomized controlled trial

Background and objectives

Fascia iliaca compartment block (FICB) has been shown to provide excellent pain relief in patients undergoing total hip arthroplasty (THA). However, the analgesic efficacy of FICB, in comparison with periarticular infiltration (PAI) for THA, has not been evaluated. This randomized, controlled, observer-blinded study was designed to compare suprainguinal FICB (SFICB) with PAI in patients undergoing THA via posterior approach.

Methods

After institutional review board approval, 60 consenting patients scheduled for elective THA were randomized to one of two groups: ultrasound-guided SFICB block or PAI. The local anesthetic solution for both the groups included 60 mL ropivacaine 300 mg and epinephrine 150 µg. The remaining aspects of perioperative care, including general anesthetic and non-opioid multimodal analgesic techniques, were standardized. An investigator blinded to group allocation documented pain scores at rest and with movement and supplemental opioid requirements at various time points. Patients were evaluated for sensory changes and quadriceps weakness in the operated extremity.

Results

There were no differences between the groups with respect to demographics, intraoperative opioid use, duration of surgery, recovery room stay, nausea scores, need for rescue antiemetics, time to ambulation and time to discharge readiness as well as 48 hours postoperative opioid requirements. The pain scores at rest and with movement also were similar at all time points. Significantly more patients in the SFICB group experienced muscle weakness at 6 hours after surgery.

Conclusions

Under the circumstances of our study, in patients undergoing THA, SFICB provided the similar pain relief compared with PAI, but was associated with muscle weakness at 6 hours postoperatively.

Trial registration number

NCT02658240.

Decreased Platelet Number and Function and Increased Fibrinolysis Contribute to Postoperative Bleeding in Cardiopulmonary Bypass Patients

We simultaneously evaluated platelet and fibrinolytic parameters to assess their individual and combined contributions to postoperative blood loss in cardiopulmonary (CP) bypass patients. Platelet count, platelet aggregability, hematocrit, plasminogen (PLG) concentration, alpha2-antiplasmin (AP) concentration, free protease activity (fPA), and antithrombin-III (AT-III) were measured in nine patients undergoing surgery using cardiopulmonary bypass. Chest tube drainage was used as the measure of postoperative blood loss. Hematocrit, platelet count, PT .G , AP and AT-TTT all decreased during CP bypass, with PLG and AT-III decreasing much more than dilution. During CP bypass, platelet aggregability to A DP did not change significantly from pre-bypass, but aggregability to arachidonic acid (AA) decreased significantly. Following protamine administration there was a large increase (83%) in fPA, the platelet count showed a further drop (from 61 % to 50% of pre-bypass levels) . and platelet aggregability decreased significantly (from 95% to 34% of prebypass levels for ADP, and from 55% to 11.9% for A A). Chest tube drainage during the first four postoperative hours correlated positively (p <0.05) with the combination of increase in free protease activity and decrease in platelet count. The total chest tube drainage correlated significantly with the combination of decrease in platelet count and the decrease in platelet aggregability. These combinations of changes correlated significantly with postoperative blood loss whereas the individual changes did not. These data indicate that during the early postoperative period the increased fibrinolytic activity and the decreased platelet count together contribute toward postoperative blood loss in CP bypass patients, and that during the entire first 24 hour period postoperatively the decreased platelet number and decreased platelet function are important contributors to blood loss.

Anesthesiology, automation, and artificial intelligence

There have been many attempts to incorporate automation into the practice of anesthesiology, though none have been successful. Fundamentally, these failures are due to the underlying complexity of anesthesia practice and the inability of rule-based feedback loops to fully master it. Recent innovations in artificial intelligence, especially machine learning, may usher in a new era of automation across many industries, including anesthesiology. It would be wise to consider the implications of such potential changes before they have been fully realized.

Comparison of smartphone application-based vital sign monitors without external hardware versus those used in clinical practice: a prospective trial

Use of healthcare-related smartphone applications is common. However, there is concern that inaccurate information from these applications may lead patients to make erroneous healthcare decisions. The objective of this study is to study smartphone applications purporting to measure vital sign data using only onboard technology compared with monitors used routinely in clinical practice. This is a prospective trial comparing correlation between a clinically utilized vital sign monitor (Propaq CS, WelchAllyn, Skaneateles Falls, NY, USA) and four smartphone application-based monitors Instant Blood Pressure, Instant Blood Pressure Pro, Pulse Oximeter, and Pulse Oximeter Pro. We performed measurements of heart rate (HR), systolic blood pressures (SBP), diastolic blood pressure (DBP), and oxygen saturation (SpO₂) using standard monitor and four smartphone applications. Analysis of variance was used to compare measurements from the applications to the routine monitor. The study was completed on 100 healthy volunteers. Comparison of routine monitor with the smartphone applications shows significant differences in terms of HR, SpO₂ and DBP. The SBP values from the applications were not significantly different from those from the routine monitor, but had wide limits of agreement signifying a large degree of variation in the compared values. The degree of correlation between monitors routinely used in clinical practice and the smartphone-based applications studied is insufficient to recommend clinical utilization. This lack of correlation suggests that the applications evaluated do not provide clinically meaningful data. The inaccurate data provided by these applications can potentially contribute to patient harm.

Analgesic utilization before and after rescheduling of hydrocodone in a large academic level 1 trauma center

BACKGROUND

Hydrocodone-containing products were recently rescheduled from Drug Enforcement Agency (DEA) schedule III to schedule II due to concerns of abuse and misuse. These changes went into effect on October 6, 2014.

OBJECTIVE

This quality improvement project involved a retrospective analysis to determine the effect of the DEA schedule change on prescribing habits of hydrocodone-containing products as well as the remaining schedule III and IV opioids, codeine (schedule III) and tramadol (schedule IV).

METHODS

The authors performed a medication use evaluation at our academic level 1 trauma hospital system on outpatient use of hydrocodone-containing products, tramadol, and codeine-containing products for 6 months before and 6 months after the change to schedule II using our electronic record and pharmacy system.

RESULTS

A total of 88,428 prescription orders were analyzed. Comparison of prescriptions before and after the DEA schedule changes showed hydrocodone prescriptions reduced from an average of 225.97 per day to 1.20 per day. In addition, tramadol increased from 60.04 per day to 91.85 per day and codeine from 6.81 per day to 98.94 per day.

CONCLUSIONS

Our data show a very substantial decrease in utilization of hydrocodone-containing products and concomitant increase in the utilization of tramadol and codeine products at our hospital after the DEA schedule change.

Simple Technique to Verify CO2 Diffusion with the CarbonAid� Device

It has become common practice in cardiac surgery to flood the operative field with CO₂ to facilitate deairing of the heart. However, CO₂ delivery is variable and verification of CO₂ delivery can be challenging. We report a simple, reliable method to confirm CO₂ delivery. This technique ensures that the benefits of CO₂ delivery are provided to the patient during the operation.

Hybrid percutaneous coronary intervention and minimally invasive reoperative mitral valve surgery

We report a complex case of peripheral vascular disease (PVD), coronary artery disease (CAD), and three prosthetic heart valves, who developed severe mitral regurgitation (MR) due to healed endocarditis. She was successfully managed with a hybrid approach utilizing percutaneous coronary intervention (PCI) followed by minimally invasive mitral valve surgery (MIMVS) through right minithoracotomy. This was the patient's fifth cardiac surgery and she was discharged home on the fourth postoperative day (POD).

Anticoagulation: American College of Chest Physicians guidelines for the prevention and management of postoperative atrial fibrillation after cardiac surgery

Post-cardiac surgery atrial fibrillation (AF) places patients at risk for thromboembolism and stroke, while the surgery and cardiopulmonary bypass alter the multiple factors of coagulation and may increase the tendency to bleed. It is in the context of this complex clinical picture that the physician must make decisions regarding the risks and benefits of anticoagulation therapy to lower the risk for thromboembolism and stroke associated with postoperative AF. Physicians must also weigh the usually transient and self-limited duration of new-onset postoperative AF against the potential for postoperative bleeding if anticoagulation therapy is started. No randomized, controlled clinical trials are available that specifically address the problem of anticoagulation therapy for the postoperative AF. In that context, recommendations are based on the established therapy for nonsurgical situations modified by the potential risk of bleeding in the postoperative patient.

Intraoperative Interventions

A comprehensive evidence review was conducted of the medical literature regarding the relationship between intraoperative interventions and the incidence of postoperative atrial arrhythmias, including, most commonly, atrial fibrillation (AF). Fifteen randomized, controlled studies and one large-scale concurrent cohort study were identified that reported on the following issues: systemic temperature during surgery (one report); "beating heart" surgery vs conventional bypass surgery (three reports); type of myocardial protection (five reports); the use of adjunctive posterior pericardiotomy (one report); the use of thoracic epidural anesthesia (TEA) [two reports]; the use of glucose-insulin-potassium (GIK) solutions (two reports); and the use of heparin-coated circuits for cardiopulmonary bypass (CPB) [two reports]. Based on a systematic review of the reported data and an analysis of the quality of the reported data, we recommend the following: (1) that mild hypothermia, rather than moderate hypothermia, may be effective in reducing the frequency of postoperative AF; (2) the use of posterior pericardiotomy may be a useful adjunct to reduce the frequency of postoperative AF; and (3) the use of heparin-coated CPB circuits is associated with less postoperative AF. Because of conflicting or inadequate data, we cannot conclude that the frequency of postoperative AF is affected by (1) the use of beating-heart techniques, (2) the type of myocardial protection strategy used, (3) the use of TEA, or (4) the use of GIK solutions perioperatively.

Oral glycoprotein IIb/IIIa inhibition with orbofiban in patients with unstable coronary syndromes (OPUS-TIMI 16) trial

BACKGROUND

Although intravenous glycoprotein IIb/IIIa inhibitors are beneficial in patients with acute coronary syndromes, prolonged oral IIb/IIIa inhibition might provide an additional reduction in recurrent events.

METHODS AND RESULTS

Investigators at 888 hospitals in 29 countries enrolled 10 288 patients with acute coronary syndromes, which was defined as ischemic pain at rest within 72 hours of randomization, associated with positive cardiac markers, electrocardiographic changes, or prior cardiovascular disease. Patients received aspirin and were randomized to receive, for the duration of the trial, (1) 50 mg of orbofiban twice daily (50/50 group), (2) 50 mg of orbofiban twice daily for 30 days followed by 30 mg of orbofiban twice daily (50/30 group), or (3) a placebo. The primary composite end point was death, myocardial infarction, recurrent ischemia requiring rehospitalization, urgent revascularization, or stroke. The trial was terminated prematurely because of an unexpected increase in 30-day mortality in the 50/30 orbofiban group. Mortality through 10 months was 3.7% for the placebo group versus 5.1% in the 50/30 group (P=0.008) and 4.5% in the 50/50 group (P=0.11). There were no differences in the primary end point (22.9%, 23.1%, and 22.8%, for the placebo, 50/30, and 50/50 groups, respectively). Major or severe bleeding (but not intracranial hemorrhage) was higher with orbofiban; it occurred in 2. 0%, 3.7% (P=0.0004), and 4.5% (P<0.0001) of patients, respectively. Exploratory subgroup analyses found that patients who underwent percutaneous coronary intervention had a lower mortality and a significant reduction in the composite end point (P=0.001) with orbofiban.

CONCLUSIONS

-Fixed-dose orbofiban failed to reduce major cardiovascular events and was associated with increased mortality in this broad population of patients with acute coronary syndromes; however, a benefit was observed among patients who underwent percutaneous coronary intervention.

Method for creation of the aortotomy site for saphenous vein grafts

Saphenous vein coronary artery bypass grafting requires a proximal anastomosis of the vein to the aorta. A variety of techniques have been described to create the aortotomy. We have developed a four-sided knife (Xcision Scalpel; patent pending, Research Medical, Inc, Midvale, UT) that facilitates the creation of a more uniform circular aortotomy. The purpose of this communication is to describe the knife and the technique for its use.

False aneurysm of the right internal mammary artery. Late rupture after sternotomy

This report describes a late, near-fatal rupture of a false aneurysm of the right internal mammary artery subsequent to coronary artery bypass grafting. The patient presented to us in shock due to hemorrhaging, 8 weeks after bypass surgery that had been complicated by sternal fracture, dehiscence, and infection. Emergent thoracotomy and suture ligation controlled the hemorrhage. To the best of our knowledge, this is the 1st reported case of late massive hemorrhage caused by injury to an internal mammary artery after sternotomy. The literature is reviewed and discussed.

Hemodynamic stabilization of acute prosthetic valve thrombosis using percutaneous catheter manipulation

Thrombosis of a tilting-disk prosthetic heart valve can be an acute and potentially life-threatening problem. Surgical thrombectomy, valve replacement, or systemic thrombolytic agents have been successfully employed in the management of such cases. Some patients, however, may not survive the acute episode long enough to receive definitive surgical therapy. For such patients, temporary hemodynamic stabilization might be achieved by re-establishing partial valve disk mobility. This report describes a technique for re-establishing valve disk mobility in an acutely compromised patient by using a percutaneously introduced "rigid" catheter to manipulate an entrapped tilting-disk valve in the aortic position.

Modulation of alloreactivity in transplant recipients by phenotypic manipulation of donor endothelium

Phenotypic manipulation of allograft endothelium to reduce immunogenicity would have a significant impact on transplantation. In this study we have demonstrated that random seeding of a heart allograft with endothelium, of host origin, not only promotes long-term survival, but reduces the requirement for pharmacologic immunosuppression. We propose that this simple technology could easily be extrapolated to the clinical arena where hypothermia and preservation solutions have allowed allografts to remain ex vivo for extended periods.

The relationship between hospital charges and a modified Parsonnet risk score

Health care now consumes approximately 14 percent of the U.S. Gross National Product (GNP). The amount of money spent on health care in America per capita and as a percentage of GNP far exceeds that of any other industrialized country. Currently, the financial burden of health care is being shouldered by government and business. The expenditure of billions of dollars of corporate profits on health care progressively undermines the global competitiveness of American business. These economic realities have emerged as the dominant driving force in health care reform. Cost control efforts to date have focused on strategies to limit inpatient hospital expenditures. The DRG prospective payment system is designed to reimburse a fixed sum based on the diagnostic category of the patient. The DRG payment is essentially independent of underlying patient characteristics that can potentially drive up expenditures. The work reported in this article was done to develop a descriptive formula that could be used to predict resource consumption in the care of patients. The financial viability of a hospital depends on its ability to predict expenditures, allocate resources, and choose its service areas correctly. Errors in financial forecasting in the era of prospective payment will result in financial failures of entire institutions.

The haemostatic effectiveness of autologous platelet rich plasma sequestered after heparin administration and institution of cardiopulmonary bypass

Preoperative harvesting and postoperative reinfusion of autologous platelet rich plasma (PRP) has been reported to decrease blood loss as well as the requirement for homologous blood transfusion following cardiopulmonary bypass (CPB). We have developed a technique of intraoperative PRP sequestration which occurs during the initial period of CPB after the patient's circulation is supported and heparin has been given (PRP+). This process does not require any additional hardware, personnel or expense and it is performed without difficulty or complication. To evaluate the effect of PRP+ sequestration and reinfusion on blood loss and homologous blood requirement after CPB, we randomly assigned 126 consecutive patients undergoing elective open heart surgery into the experimental group 1 (PRP+) (n = 64) or the control (no platelet pheresis) group 2 (n = 52). A third group (n = 10) were not included in the randomization. Patients in group 3 had PRP prepared by conventional techniques (PRPc) prior to heparin administration and given to the patient after protamine infusion. Aggregation and activation studies were performed on the PRP+, PRPc, and blood bank platelets (BBP). Per cent aggregation of PRP in response to ADP was superior to that of BBP. There were no significant differences in ADP induced aggregation between PRP+ and PEPc. There was no significant difference in platelet activation (CD62) or number between the three groups. Patients infused with PRP+ showed significantly increased aggregation to ADP when compared with untreated patients 120 minutes after return to the ICW. Furthermore, more homologous haemostatic components (platelets/fresh frozen plasma) were required in the control group. We have demonstrated that collection of autologous PRP+ after administration of heparin does not interfere with its haemostatic effectiveness compared with PRPc prepared before the initiation of bypass. Moreover, this can be performed universally in haemodynamically unstable patients without any additional costs.

Cardiopulmonary bypass with adequate flow and perfusion pressures prevents endotoxaemia and pathologic cytokine production

Endotoxin and cytokine inflammatory mediators comprise the afferent and efferent limbs of the 'acute phase response'. During cardiopulmonary bypass (CPB) there may be gut translocation of endotoxin and contact activation of lymphocytes. It has been hypothesized that the haemodynamic instability encountered following CPB is caused by the 'acute phase response'. In this study we attempted to quantify the acute phase response in patients undergoing open-heart surgery and determine the influence of these cytokines on perioperative morbidity. Four perioperative blood samples were drawn from 20 consecutive patients undergoing coronary artery bypass grafting (CABG). These samples were assayed for endotoxin and four cytokines. In all cases the cardiac index was maintained > 2.4 l/min/m2 during nonpulsatile normothermic bypass (37 degrees C) and > 1.8 l/min/m2 during nonpulsatile hypothermic bypass (28 degrees C), and the perfusion pressure > 60 mmHg. Endotoxin was not detected in any of the test samples despite positive nonpatient controls. Interleukin 6 (IL-6) and tumour necrosis factor (TNF) were not detected despite an assay sensitivity of 80 and 10 pg/ml, respectively. TNF was detectable with an assay sensitivity of 0.5 pg/ml although there were no significant differences within the group. Interleukin 1 (IL-1) was detected (range = 0.98 - 9.09 ng/ml) in patients and again there were no trends within the group. The platelet activating factor (PAF) values peaked at crossclamp release (1.3 ng/ml versus a baseline of 0.2 ng/ml); however, there was no significant difference within the study.

Management of massive pulmonary thromboembolism complicating diabetic ketoacidosis

Intravascular volume depletion secondary to diabetic ketoacidosis may result in thrombosis of major blood vessels. Without anticoagulation these thrombi can embolize to the lungs and compromise cardiopulmonary function. When this occurs early surgical pulmonary embolectomy is indicated to salvage a failing right heart.

Intraoperative procurement of autologous fibrin glue

A method of intraoperative procurement of autologous fibrin glue is described. The relative efficacy of our autologous preparation is compared with that of fibrin glue made with homologous cryoprecipitate. Experimentally, the fibrinogen content and the strength are less than those found in cryoprecipitate and appear related to the fibrinogen content of the autologous plasma used as substrate in the fibrin glue reaction. Clinically, no significant differences are noted in the performance of autologous fibrin glue. We believe the absence of the risk of blood-borne infection with the autologous product is a major advantage.