Fast-Track Cardiac Anesthesia: Choice of Anesthetic Agents and Techniques

To evaluate the analgesic effectiveness of bilateral erector spinae plane block versus thoracic epidural analgesia in open cardiac surgeries approached through midline sternotomy

BACKGROUND

The efficacy of the erector spinae plane (ESP) block in mitigating postoperative pain has been shown for a range of thoracic and abdominal procedures. However, there is a paucity of literature investigating its impact on postoperative analgesia as well as its influence on weaning and subsequent recovery in comparison to thoracic epidural analgesia (TEA) in median sternotomy-based approach for open-cardiac surgeries and hence the study.

METHODS

Irrespective of gender or age, 74 adult patients scheduled to undergo open cardiac surgery were enrolled and randomly allocated into two groups: the Group TEA (thoracic epidural block) and the Group ESP (bilateral Erector Spinae Plane block). The following variables were analysed prospectively and compared among the groups with regard to pain control, as determined by the VAS Scale both at rest (VASR) and during spirometry (VASS), time to extubation, quantity and frequency of rescue analgesia delivered, day of first ambulation, length of stay in the intensive care unit (ICU), and any adverse cardiac events (ACE), respiratory events (ARE), or other events, if pertinent.

RESULTS

Clinical and demographic variables were similar in both groups. Both groups had overall good pain control, as determined by the VAS scale both at rest (VASR) and with spirometry (VASS) with Group ESP demonstrating superior pain regulation compared to Group TEA during the post-extubation period at 6, 9, and 12 h, respectively (P > 0.05). Although statistically insignificant, the postoperative mean rescue analgesic doses utilised in both groups were comparable, but there was a higher frequency requirement in Group TEA. The hemodynamic and respiratory profiles were comparable, except for a few arrhythmias in Group TEA. With comparable results, early recovery, fast-track extubation, and intensive care unit (ICU) stay were achieved.

CONCLUSIONS

The ESP block has been found to have optimal analgesic effects during open cardiac surgery, resulting in a decreased need for additional analgesic doses and eliminating the possibility of a coagulation emergency. Consequently, it presents itself as a safer alternative to the potentially invasive thoracic epidural analgesia (TEA).

Comparison Between Fast-Track and Conventional Anesthesia for Children Undergoing Closure of Ventricular Septal Defects: A Systematic Review and Meta-Analysis

Ventricular septal defect (VSD) is common in pediatric patients. This study aimed to evaluate the safety and effectiveness of using fast-track anesthesia and comparing it to traditional anesthesia, among children undergoing a transthoracic device closure for VSD. A systematic review following the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted. Relevant literature was identified through specific search terms in the Scopus, Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica database (Embase), Web of Science, The Cochrane Central Register of Controlled Trials (CENTRAL), and Google Scholar databases. The inclusion criteria focused on observational studies that compared fast-track anesthesia with conventional anesthesia in pediatric VSD closure cases. Data extraction, quality assessment, and meta-analysis were performed using standard differences in means. Initially, 6,535 papers were identified, and subsequent screening of titles and abstracts led to the inclusion of four retrospective studies from a total of 51 studies. The analysis encompassed 477 patients, with 235 in the fast-track anesthesia group and 242 in the conventional anesthesia group. No statistically significant disparities were observed between the two groups concerning the operative duration and hemodynamic variations post-intubation or post-procedure (P >0.05). Nevertheless, the fast-track anesthesia group demonstrated significantly reduced healthcare expenses as well as shorter periods of mechanical ventilation, ICU stay, and overall hospitalization compared to conventional anesthesia (P <0.05). The use of fast-track anesthesia in combination with transthoracic device closure for VSD demonstrates a safe and effective approach for pediatric patients. This approach results in reduced healthcare costs (10,000 Renminbi (RMB)) and shorter durations of mechanical ventilation, ICU admission, and hospitalization compared to conventional anesthesia. Further clinical trials are necessary to confirm these results and assess long-term outcomes.

Comparison of transversus thoracis muscle plane block and pecto-intercostal fascial plane block for enhanced recovery after pediatric open-heart surgery

BACKGROUND

Effective analgesia after cardiac surgery contributes to enhanced recovery.

AIM

To compare the perioperative analgesic effectiveness of Transversus Thoracis Muscle Plane Block (TTPB) and Pecto-Intercostal-Fascial Plane Block (PIFB) for controlling post-sternotomy pain in the pediatric population for ultrafast track cardiac surgery.

METHODS

Double-blind randomized study of 60 children, 2-12 years old, undergoing cardiac surgery via median sternotomy in whom a bilateral ultrasound-guided TTPB or TIBP block was performed preemptively.

RESULTS

Epidemiologic data of both groups were comparable. TTPB group had a lower median Modified Objective Pain Score (MOPS) all over the time postoperatively. Fentanyl consumption was significantly lower in TTBP group compared with PIFB group, only 4/30 received supplemental fentanyl during surgery in the TTPB group vs. 11/30 in the PIFB group (p = 0.033). The median [interquartile] values of postoperative fentanyl consumption were significantly lower in the TTBP compared with PIFB group: 12.0 [10.0-12.0] vs. 15.0 [15.0-16.0] µg/kg (p < 0.001), respectively. First rescue analgesia was later in the TTPB group compared to the PIFB group with median times of 7.25 and 5.0 hours, respectively (p < 0.001). Both groups had a comparable ICU length of stay (p = 0.919), with a median of 3 days. Furthermore, in the PIFB group, the incidence of non-sternal wound chest pain (53.3%) was significantly higher than in the TTPB group (3.3%) (p < 0.05).

CONCLUSION

TTPB and PIFB are safe regional blocks that could enhance recovery after pediatric cardiac surgery. In our series, TTPB provided better and longer-lasting postoperative analgesia with less incidence of non-sternal wound pain than PIFB.

Non-interventional Feasibility Assessment for Fast-Track Cardiac Anesthesia

Background The introduction of fast-track extubation procedures following cardiac surgery has significantly shortened hospitalization duration in intensive care units (ICUs). Early extubation is the most crucial step in getting out of the ICU early and providing ideal patient circulation. In times of crisis such as pandemics, it is vital to provide rapid flow through the hospital to prevent the postponement or inability to operate on patients awaiting surgery. This study aimed to determine the obstacles to early extubation in patients undergoing cardiac surgery and the perioperative characteristics that were affected in terms of fast-track extubation. Methodology This was an observational, cross-sectional study with data collected prospectively from October 1 to November 30, 2021. Preoperative data and comorbidities were recorded. Intraoperative and postoperative data were recorded and analyzed. Intraoperative cross-clamp duration, cardiopulmonary bypass duration, length of operation, and erythrocytes (red blood cells) transfused were recorded for each patient. Early postoperative clinical conditions were defined in patients whose mechanical ventilation duration exceeded eight hours (such as pulmonary complications, cardiovascular complications, renal complications, neurological conditions, and infective complications ). The length of ICU stay (hours), length of hospital stay (days), return to the ICU, reasons for return to the ICU, and overall hospital mortality were investigated. A total of 226 patients were included in the study. Patients were divided into two groups: extubated within eight hours (FTCA, fast-track cardiac anesthesia) and late extubation (after eight hours) postoperatively, and the data were evaluated accordingly. Results While 138 (61.1%) of the patients were extubated in eight hours or less, 88 (38.9%) patients were extubated after more than eight hours. The most common complications (55.7%) in patients with late extubation were cardiovascular complications, followed by respiratory complications (15.9%), and the surgeon's refusal (15.9%). In the logistic model created with the independent variables affecting the extubation time, the American Society of Anesthesiologists score and red blood cell transfusion were risk factors for longer extubation time. Conclusions In our research to reveal the feasibility of and barriers to FTCA, it was found that cardiac and respiratory problems were the most common reasons for delayed extubation. Due to the refusal of the surgical team, it was observed that some patients remained intubated despite meeting the FTCA requirements. It was considered the most improvable obstacle. Regarding cardiovascular complications, the team should aim to optimally control patient comorbidities in the preoperative period, reduce the use of red blood cell transfusions, and ensure that the entire team is updated on current extubation protocols, in particular surgeons and anesthesiologists.

Pulmonary artery perfusion versus no perfusion during cardiopulmonary bypass for open heart surgery in adults

BACKGROUND

Available evidence has been inconclusive on whether pulmonary artery perfusion during cardiopulmonary bypass (CPB) is associated with decreased or increased mortality, pulmonary events, and serious adverse events (SAEs) after open heart surgery. To our knowledge, no previous systematic reviews have included meta-analyses of these interventions.

OBJECTIVES

To assess the benefits and harms of single-shot or continuous pulmonary artery perfusion with blood (oxygenated or deoxygenated) or a preservation solution compared with no perfusion during cardiopulmonary bypass (CPB) in terms of mortality, pulmonary events, serious adverse events (SAEs), and increased inflammatory markers for adult surgical patients.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Science Citation Index Expanded, and advanced Google for relevant studies. We handsearched retrieved study reports and scanned citations of included studies and relevant reviews to ensure that no relevant trials were missed. We searched for ongoing trials and unpublished trials in the World Health Organization International Clinical Trials Registry Platform (ICTRP) and at clinicaltrials.gov (4 July 2017). We contacted medicinal firms producing preservation solutions to retrieve additional studies conducted to examine relevant interventions.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that compared pulmonary artery perfusion versus no perfusion during CPB in adult patients (≧ 18 years).

DATA COLLECTION AND ANALYSIS

Two independent review authors extracted data, conducted fixed-effect and random-effects meta-analyses, and calculated risk ratios (RRs) or odds ratios (ORs) for dichotomous outcomes. For continuous data, we have presented mean differences (MDs) and 95% confidence intervals (CIs) as estimates of the intervention effect. To minimize the risk of systematic error, we assessed risk of bias of included trials. To reduce the risk of random errors caused by sparse data and repetitive updating of cumulative meta-analyses, we applied Trial Sequential Analyses (TSAs). We used GRADE principles to assess the quality of evidence.

MAIN RESULTS

We included in this review four RCTs (210 participants) reporting relevant outcomes. Investigators randomly assigned participants to pulmonary artery perfusion with blood versus no perfusion during CPB. Only one trial included the pulmonary artery perfusion intervention with a preservation solution; therefore we did not perform meta-analysis. Likewise, only one trial reported patient-specific data for the outcome "pulmonary events"; therefore we have provided no results from meta-analysis. Instead, review authors added two explorative secondary outcomes for this version of the review: the ratio of partial pressure of oxygen in arterial blood (PaO₂) to fraction of inspired oxygen (FiO₂); and intubation time. Last, review authors found no comparable data for the secondary outcome inflammatory markers.The effect of pulmonary artery perfusion on all-cause mortality was uncertain (Peto OR 1.78, 95% CI 0.43 to 7.40; TSA adjusted CI 0.01 to 493; 4 studies, 210 participants; GRADE: very low quality). Sensitivity analysis of one trial with overall low risk of bias (except for blinding of personnel during the surgical procedure) yielded no evidence of a difference for mortality (Peto OR 1.65, 95% CI 0.27 to 10.15; 1 study, 60 participants). The TSA calculated required information size was not reached and the futility boundaries did not cross; thus this analysis cannot refute a 100% increase in mortality.The effect of pulmonary artery perfusion with blood on SAEs was likewise uncertain (RR 1.12, 95% CI 0.66 to 1.89; 3 studies, 180 participants; GRADE: very low quality). Data show an association between pulmonary artery perfusion with blood during CPB and a higher postoperative PaO₂/FiO₂ ratio (MD 27.80, 95% CI 5.67 to 49.93; 3 studies, 119 participants; TSA adjusted CI 5.67 to 49.93; GRADE: very low quality), although TSA could not confirm or refute a 10% increase in the PaO₂/FiO₂ ratio, as the required information size was not reached.

AUTHORS' CONCLUSIONS

The effects of pulmonary artery perfusion with blood during cardiopulmonary bypass (CPB) are uncertain owing to the small numbers of participants included in meta-analyses. Risks of death and serious adverse events may be higher with pulmonary artery perfusion with blood during CPB, and robust evidence for any beneficial effects is lacking. Future randomized controlled trials (RCTs) should provide long-term follow-up and patient stratification by preoperative lung function and other documented risk factors for mortality. One study that is awaiting classification (epub abstract with preliminary results) may change the results of this review when full study details have been published.

Use of Provider Debriefing to Improve Fast-Track Extubation Rates Following Cardiac Surgery at an Academic Medical Center

When used in appropriate patient populations, fast-track extubation (FTE) anesthetic techniques and intensive care unit (ICU) protocols safely reduce intubation times, ICU length of stay, and resource utilization. The authors hypothesized that perioperative provider debriefing on success or failure of FTE would improve FTE success. This retrospective observational study included consecutive patients undergoing elective coronary artery bypass graft (CABG), valve, or combined CABG/valve surgery between February 2015 and May 2016 (N = 313). Throughout the intervention period, a briefing was distributed on postoperative day 1 to the anesthesiology providers responsible for operative care of the patient detailing success or failure of FTE and perioperative characteristics. The preintervention FTE success rate of 55.6% significantly improved to 72.8% in the intervention group ( P = .022). When combined with a continuous interdepartmental review process, provider debriefing improved FTE success. Perioperative provider debriefing requires minimal resources for implementation and can easily be replicated in other cardiac surgery centers.

Comparison of the Effect of Anesthesia With Midazolam-Fentanyl Versus Propofol-Remifentanil on Bispectral Index in Patients Undergoing Coronary Artery Bypass Graft

The aim of this study was to compare the effect of anesthesia with midazolam-fentanyl versus propofol-remifentanil on the BIS (bispectral index) in patients undergoing coronary artery bypass grafting (CABG). Sixty-four patients undergoing CABG were randomly assigned to one of two study groups: midazolam-fentanyl (MF, N= 32) or propofol-remifentanil (PR, N= 32). The BIS was measured before induction of anesthesia, five minutes after induction of anesthesia, at skin incision, sternotomy, pericardiotomy, aorta cannulation, onset of cardiopulmonary bypass, during rewarming, five minutes after separation from cardiopulmonary bypass, at thorax closure, and at the end of the surgery. There were no significant differences between the two groups with regard to age and gender. The difference in mean BIS between the two groups was significant (P < 0.05) at all times, except before induction, five minutes after induction, at skin incision and on rewarming. Changes in the BIS were lower in the PR group than in the MF group. Both techniques can provide adequate anesthesia in patients undergoing CABG. However, the probability of awareness during anesthesia is lower with propofol-remifentanil than with midazolam-fentanyl.

High Thoracic Epidural in Cardiac Anesthesia

High thoracic epidural analgesia (HTEA) offers a distinctive opportunity to enhance postoperative recovery for the thoracic surgery patient. In the modern hospital setting with day of admission surgery, the logistics of insertion of the epidural catheter has become increasingly difficult. The greatest limitation to its use might be the believed increased risk of epidural hematoma associated with anticoagulation during cardiopulmonary bypass. The aim of this review is to give an overview of complications and effect on outcomes with focus on cardiac performance and postoperative glycemic control and kidney function. Patients with epidurals may have improved postoperative pulmonary function and shorter ventilation time, while impact on length of stay in the intensive care unit and hospital is not as evident. HTEA is effective in pain management, attenuates perioperative stress and seems to improve postoperative blood glucose control. Whether HTEA improves recovery and facilitates fast-track is still to be confirmed. With regard to serious postoperative complications, there is evidence of reduction in supraventricular arrhythmias and lower frequency of postoperative acute kidney injury and dialysis. There are some indications of lower short term mortality and frequency of postoperative myocardial infarctions, but only as a combined outcome. The present short-term mortality of 1% to 2% should be compared with the most pessimistic frequency of epidural hematoma being 1 in 4600 patients.

Clinical and economic impact of substituting dexmedetomidine for propofol due to a US drug shortage: examination of coronary artery bypass graft patients at an urban medical centre

BACKGROUND

Propofol has reduced healthcare costs in coronary artery bypass graft (CABG) surgery patients by decreasing post-operative duration of mechanical ventilation. However, the US shortage of propofol necessitated the use of alternative agents.

OBJECTIVE

This study sought to evaluate clinical and economic implications of substituting dexmedetomidine for propofol in patients undergoing CABG surgery.

METHODS

This was a retrospective cohort study. Patients undergoing isolated, elective CABG surgery and sedated with either propofol or dexmedetomidine during the study period were included. The cohorts were matched 1:1 based on important characteristics. The primary outcome was the number of patients achieving a post-operative duration of mechanical ventilation ≤6 h. Secondary outcomes were post-operative intensive care unit (ICU) length of stay (LOS) ≤48 h, total post-operative LOS ≤5 days, the need for adjunctive opioid therapy and associated cost savings. Variables recorded included patient demographics, co-morbid medical conditions, health risks, sedation drug doses, post-operative medical complications and sedation-related adverse events. Univariate and multivariate analyses were completed to examine the relationship between these covariates and post-operative LOS. The cost analysis consisted of examination of the net financial benefit (or cost) of choosing dexmedetomidine versus propofol in the study population, with utilisation observed in the study converted to costs using institutional data from the Premier database.

RESULTS

Eighty-four patients were included, with 42 patients per cohort. Mechanical ventilation duration ≤6 h was achieved in 24 (57.1 %) versus 7 (16.7 %) in the dexmedetomidine and propofol cohorts, respectively (p < 0.001). More patients treated with dexmedetomidine achieved ICU LOS ≤48 h (p < 0.05) and total hospital LOS ≤5 days (p < 0.05), as compared with the propofol group. Multivariate analysis revealed that having one or more post-operative medical complication was the most significant predictor of increased post-operative LOS, whereas choosing dexmedetomidine was also significant in terms of reduced post-operative LOS. The estimated net financial benefit of choosing dexmedetomidine versus propofol was US$2,613 per patient (year 2012 value).

CONCLUSIONS

Findings suggest that use of dexmedetomidine as an alternative to propofol for sedation of CABG patients post-operatively contributes to reduced mechanical ventilation time, ICU LOS and post-operative LOS. Higher drug costs resulting from the propofol shortage were offset by savings in post-operative room and board costs. Additional savings may be possible by preventing medical complications to the extent possible.

Pulmonary perfusion with oxygenated blood or custodiol HTK solution during cardiac surgery for postoperative pulmonary function in COPD patients: a trial protocol for the randomized, clinical, parallel group, assessor and data analyst blinded Pulmonary Protection Trial

Background

Five to thirty percent of patients undergoing cardiac surgery present with chronic obstructive pulmonary disease (COPD) and have a 2- to 10-fold higher 30-day mortality risk. Cardiopulmonary bypass (CPB) creates a whole body systemic inflammatory response syndrome (SIRS) that could impair pulmonary function. Impaired pulmonary function can, however, be attenuated by pulmonary perfusion with oxygenated blood or custodiol HTK (histidine-tryptophan-ketoglutarate) solution.

Methods/Design

The Pulmonary Protection Trial (PP-Trial) randomizes 90 patients undergoing CPB-dependent cardiac surgery to evaluate whether pulmonary perfusion with oxygenated blood or custodiol HTK solution reduces postoperative pulmonary dysfunction in COPD patients. Further, we aim for a non-randomized evaluation of postoperative pulmonary function after transcatheter aortic-valve implantation (TAVI). The primary outcome measure is the oxygenation index measured from anesthesia induction to the end of surgery and until 24 hours after anesthesia induction for a total of six evaluations.

Discussion

Patients with COPD may be impaired by hypoxemia and SIRS. Thus, prolonged recovery and even postoperative complications and death may be reflected by the degree of hypoxemia and SIRS. The limited sample size does not aim for confirmatory conclusions on mortality, cardiovascular complications or risk of pneumonia and sepsis, but the PP-Trial is considered an important feasibility trial paving the road for a multicenter confirmatory trial.

Trial registration

ClinicalTrials.gov: NCT01614951.

Evidence basis for regional anesthesia in multidisciplinary fast-track surgical care pathways

Fast-track programs have been developed with the aim to reduce perioperative surgical stress and facilitate patient's recovery after surgery. Potentially, regional anesthesia and analgesia techniques may offer physiological advantages to support fast-track methodologies in different type of surgeries. The aim of this article was to identify and discuss potential advantages offerred by regional anesthesia and analgesia techniques to fast-track programs.In the first section, the impact of regional anesthesia on the main elements of fast-track surgery is addressed. In the second section, procedure-specific fast-track programs for colorectal, hernia, esophageal, cardiac, vascular, and orthopedic surgeries are presented. For each, regional anesthesia and analgesia techniques more frequently used are discussed. Furthermore, clinical studies, which included regional techniques as elements of fast-track methodologies, were identified. The impact of epidural and paravertebral blockade, spinal analgesia, peripheral nerve blocks, and new regional anesthesia techniques on main procedure-specific postoperative outcomes is discussed. Finally, in the last section, implementations required to improve the role of regional anesthesia in the context of fast-track programs are suggested, and issues not yet addressed are presented.

Mini cardiopulmonary bypass: Anesthetic considerations

This review article is going to elaborate on the description, components, and advantages of mini-cardiopulmonary bypass (mini-CPB), with special reference to the anesthetic management and fast track anesthesia with mini-CPB. There are several clinical advantages of mini-CPB like, reduced inflammatory reaction to the pump, reduced need for allogenic blood transfusion and lower incidence of postoperative neurological complications. There are certainly important points that have to be considered by anesthesiologists to avoid sever perturbation in the cardiac output and blood pressure during mini-CPB. Fast-track anesthesia provides advantages regarding fast postoperative recovery from anesthesia, and reduction of postoperative ventilation time. Mini bypass offers a sound alternative to conventional CPB, and has definite advantages. It has its limitations, but even with that it has a definite place in the current practice of cardiac surgery.

Epidural anesthesia and postoperative analgesia with ropivacaine and fentanyl in off-pump coronary artery bypass grafting: a randomized, controlled study

Background

Our aim was to assess the efficacy of thoracic epidural anesthesia (EA) followed by postoperative epidural infusion (EI) and patient-controlled epidural analgesia (PCEA) with ropivacaine/fentanyl in off-pump coronary artery bypass grafting (OPCAB).

Methods

In a prospective study, 93 patients were scheduled for OPCAB under propofol/fentanyl anesthesia and randomized to three postoperative analgesia regimens aiming at a visual analog scale (VAS) score < 30 mm at rest. The control group (n = 31) received intravenous fentanyl 10 μg/ml postoperatively 3-8 mL/h. After placement of an epidural catheter at the level of Th₂-Th₄ before OPCAB, a thoracic EI group (n = 31) received EA intraoperatively with ropivacaine 0.75% 1 mg/kg and fentanyl 1 μg/kg followed by continuous EI of ropivacaine 0.2% 3-8 mL/h and fentanyl 2 μg/mL postoperatively. The PCEA group (n = 31), in addition to EA and EI, received PCEA (ropivacaine/fentanyl bolus 1 mL, lock-out interval 12 min) postoperatively. Hemodynamics and blood gases were measured throughout 24 h after OPCAB.

Results

During OPCAB, EA decreased arterial pressure transiently, counteracted changes in global ejection fraction and accumulation of extravascular lung water, and reduced the consumption of propofol by 15%, fentanyl by 50% and nitroglycerin by a 7-fold, but increased the requirements in colloids and vasopressors by 2- and 3-fold, respectively (P < 0.05). After OPCAB, PCEA increased PaO₂/FiO₂ at 18 h and decreased the duration of mechanical ventilation by 32% compared with the control group (P < 0.05).

Conclusions

In OPCAB, EA with ropivacaine/fentanyl decreases arterial pressure transiently, optimizes myocardial performance and influences the perioperative fluid and vasoactive therapy. Postoperative EI combined with PCEA improves lung function and reduces time to extubation.

Trial Registration

NCT01384175

[Early extubation in cardiac surgery]

INTRODUCTION

An early extubation in cardiac surgery (fast track cardiac anaesthesia) refers to mechanical ventilation during 1-6 hours after the intervention, the extubation criteria being the same as for any other surgery. Different protocols have been established for managing patients undergoing fast track anaesthesia, with high-thoracic epidural anaesthesia being increasingly used in the last few years.

MATERIAL AND METHODS

Thirty-five consecutive patients scheduled for OPCAB surgery, who were planned for very fast track cardiac anaesthesia (planned extubation within one hour after the end of the operation), were included in the study. Combined high-thoracic epidural and general anaesthesia was performed in all patients, with bupivacain as a local anaesthetic and inhalational or intravenous anesthetic used for general anaesthesia.

RESULTS

Thirty three of 35 patients (94.3%) were extubated early, with the mean duration of the mechanical ventilation of 56 +/- 92 minutes. Very fast track cardiac anaesthesia was performed successfully in 24/35 (68.8%) patients; these patients had higher ejection fraction, lower Euroscore, shorter duration of the surgery, and fewer numbers of grafts, as compared to the patients extubated early. Euroscore was the only independent predictor of the early extubation (higher score--longer mechanical ventilation time).

DISCUSSION AND CONCLUSION

Our results suggest that high-toracic epidural anaesthesia enables successful early tracheal extubation in the population of patients scheduled for OPCAB cardiac surgery. We had no complications related to this type of anaesthesia and very good perioperative results.

Incentive spirometry with expiratory positive airway pressure reduces pulmonary complications, improves pulmonary function and 6-minute walk distance in patients undergoing coronary artery bypass graft surgery

BACKGROUND

The use of the incentive spirometry (IS) with expiratory positive airway pressure (EPAP) to prevent postoperative pulmonary complications (PPC) after coronary artery bypass graft (CABG) is not well established. This study sought to determine the effects of IS+EPAP after CABG.

METHODS

Thirty-four patients undergoing CABG were randomly assigned to a control group or IS+EPAP group. Maximal respiratory pressures, pulmonary function test, 6-minute walk test and chest x-ray were performed at baseline as well as 1 week and 1 month after CABG.

RESULTS

Maximal inspiratory pressure was significantly higher in the IS+EPAP group compared to controls at both 1 week and 1 month (P<.001). Maximal expiratory pressure was significantly higher at 1 month compared to 1 week in IS+EPAP group (P<.01). At 1 month, forced vital capacity and forced expiratory volume in 1 second was significantly higher in IS+EPAP compared to controls (P<.05). Inspiratory capacity was higher at 1 month in IS+EPAP group compared to controls (P<.05). The distance walked in 6-minute walk test was higher at 1 month in IS+EPAP group (P<.001) compared to controls. Lastly, radiological injury score at 1 week was lower in IS+EPAP compared to controls (P<.004).

CONCLUSIONS

In patients undergoing CABG, IS+EPAP results in improved pulmonary function and 6-minute walk distance as well as a reduction in PPC.

Mild Hypercapnia After Uncomplicated Heart Surgery Is Not Associated With Hemodynamic Compromise

OBJECTIVE

The aim of this study was to examine the effects of small changes in PaCO(2) on hemodynamic parameters after uncomplicated heart surgery with cardiopulmonary bypass.

DESIGN

This was a prospective, randomized crossover study.

SETTING

A large academic medical center.

PARTICIPANTS

Twenty-four subjects who were scheduled for elective cardiac surgery were enrolled in this study.

INTERVENTIONS

Each subject underwent the normal procedures that are associated with cardiac surgery. General anesthesia, including muscle relaxation, were continued in the immediate postoperative period. Measured tidal volumes and minute ventilation were kept constant for the duration of the study. Target PaCO(2) concentrations of 30, 40, and 50 mmHg were achieved by adding varying amounts of exogenous CO(2) gas to the inhaled oxygen. Various measurements were made at each target PaCO(2), including cardiac index, mixed venous oxygen saturation, blood pressure, heart rate, and pulmonary artery pressure.

MEASUREMENTS AND MAIN RESULTS

Twenty-four patients were enrolled. Seven were withdrawn before commencement of the study. The cardiac index increased when the PaCO(2) was increased from 30 to 40 mmHg (p < 0.001) and remained unchanged between 40 and 50 mmHg. Mixed venous oxygen saturation increased (p < 0.001) with elevations in PaCO(2) up to 50 mmHg and decreased again when the PaCO(2) was returned to 30 mmHg. The blood pressure decreased (p < 0.001) with increasing PaCO(2). The pulmonary pressure increased (p < 0.001) with elevations in PaCO(2). No patient became hemodynamically unstable or had any arrhythmias.

CONCLUSION

The findings of this study suggest that unless there is a specific contraindication to mild hypercapnia, such as pulmonary hypertension or hemodynamic instability, concerns about mild respiratory acidosis should not prevent weaning of sedation and mechanical ventilation after uncomplicated heart surgery.

The use of pre-operative intrathecal morphine for analgesia following coronary artery bypass surgery

With the emergence of rapid extubation protocols following cardiac surgery, providing adequate analgesia in the early postoperative period is important. This prospective randomised double-blind study investigated the benefits of pre-operative intrathecal administration of low dose morphine in patients undergoing coronary artery bypass graft surgery. Postoperative analgesia, pulmonary function, stress response and postoperative recovery profile were assessed. Thirty patients were allocated into two groups, receiving either 500 mug of morphine intrathecally prior to anaesthesia and intravenous patient-controlled analgesia with morphine postoperatively following tracheal extubation, or only postoperative intravenous patient-controlled analgesia. In the intrathecal group, the total consumption of intravenous morphine following surgery was significantly reduced by 40% and patients reported lower pain scores at rest, during the first 24 h following extubation. Peak expiratory flow rate was greater and postoperative catecholamine release was significantly lower. Patients in the control group had a higher incidence of reduced respiratory rate following extubation.