Jennifer Cogan

Innovative Approaches in the Perioperative Care of the Cardiac Surgical Patient in the Operating Room and Intensive Care Unit

Perioperative care for cardiac surgery is undergoing rapid evolution. Many of the changes involve the application of novel technologies to tackle common challenges in optimizing perioperative management. Herein, we illustrate recent advances in perioperative management by focusing on a number of novel components that we judge to be particularly important. These include: the introduction of brain and somatic oximetry; transesophageal echocardiographic hemodynamic monitoring and bedside focused ultrasound; ultrasound-guided vascular access; point-of-care coagulation surveillance; right ventricular pressure monitoring; novel inhaled treatment for right ventricular failure; new approaches for postoperative pain management; novel approaches in specialized care procedures to ensure quality control; and specific approaches to optimize the management for postoperative cardiac arrest. Herein, we discuss the reasons that each of these components are particularly important in improving perioperative care, describe how they can be addressed, and their impact in the care of patients who undergo cardiac surgery.

Reversal of decreases in cerebral saturation in high-risk cardiac surgery.

OBJECTIVES To measure the incidence of cerebral desaturation during high-risk cardiac surgery and to evaluate strategies to reverse cerebral desaturation. DESIGN Prospective observational study followed by a randomized controlled study with 1 intervention group and 1 control group. SETTING Tertiary care center specialized in cardiac surgery. PARTICIPANTS All patients were scheduled for high-risk cardiac surgery, 279 consecutive patients in the prospective study and 48 patients in the randomized study. INTERVENTIONS An algorithmic approach of strategies to reverse cerebral desaturation. In the control group, no attempts were made to reverse cerebral desaturation. MEASUREMENTS AND MAIN RESULTS Cerebral saturation was measured using near-infrared reflectance spectroscopy. A decrease of 20% from baseline for 15 seconds defined cerebral desaturation. The success or failure of the interventions was noted. Demographic data were collected. Models for predicting the probability and the reversal of cerebral desaturation were based on multiple logistic regressions. In the randomized study, 12 hours of measurements were continued in the intensive care unit without interventions. Differences in desaturation load (% desaturation × time) were compared between groups. Half of the high-risk patients had cerebral desaturation that could be reversed 88% of the time. Interventions resulted in smaller desaturation loads in the operating room and in the intensive care unit. CONCLUSIONS Cerebral desaturation in high-risk cardiac surgery is frequent but can be reversed most of the time resulting in a smaller desaturation load. A large randomized study will be needed to measure the impact of reversing cerebral desaturation on patients outcome.

Evaluation of Autonomic Reserves in Cardiac Surgery Patients

OBJECTIVE Autonomic nervous system dysfunction is a well-recognized but rarely evaluated risk factor for patients undergoing cardiac surgery. By measuring autonomic reserves in patients scheduled for cardiac surgery, the authors aimed to identify those with autonomic dysfunction and to evaluate their risk of perioperative complications. DESIGN This was a prospective, observational study. SETTING The study was conducted in a single academic center. PARTICIPANTS Sixty-seven patients completed the study. INTERVENTIONS Autonomic reserves were evaluated using analysis of heart rate variability (HRV) and blood pressure variability (BPV) after a Valsalva maneuver. MEASUREMENTS AND MAIN RESULTS The patients were divided into 2 groups depending on their response to the autonomic challenge, a group with autonomic reserves (AR, n = 38) and a group with negligible autonomic reserves (NAR, n = 29). The groups were compared for baseline psychologic distress, demographic and medical profiles, autonomic response to morphine premedication and the induction of anesthesia, hemodynamic instability, the occurrence of decreases in cerebral oxygen saturation, and postoperative complications. Patients in the NAR group had significantly higher psychologic distress scores (p < 0.001), a higher baseline parasympathetic tone (p = 0.003), were unable to increase parasympathetic tone with morphine premedication, had more severe hypotension at the induction of anesthesia (p < 0.001), more episodes of decreases in cerebral saturation (p = 0.0485), and a higher overall complication rate (p = 0.0388) independent of other variables studied. CONCLUSIONS Patients with diminished autonomic reserves can be identified before cardiac surgery using analysis of HRV and BPV of the response to the Valsalva maneuver, and some evidence suggests that they may be at increased risk of perioperative complications.

Low-dose intravenous ketamine for postcardiac surgery pain: Effect on opioid consumption and the incidence of chronic pain

Background: Recent meta-analyses have concluded that low-dose intravenous ketamine infusions (LDKIs) during the postoperative period may help to decrease acute and chronic postoperative pain after major surgery. Aims: This study aims to evaluate the level of pain at least 3 months after surgery for patients treated with a postoperative LDKI versus patients who were not treated with a postoperative LDKI. Methods: Administrative and Ethics Board approval were obtained for this study. We performed a retrospective chart review for all patients receiving LDKI, and equal number of age-, sex-, and surgery-matched patients who did not receive LDKI. Low-dose ketamine was prepared using 100 mg of ketamine in 100 ml of normal saline and run between 50 and 200 mcg/kg/h. Results: We reviewed 115 patients with LDKI and 115 without LDKI. The average age was 63.1 years, 73% of the patients were men and sex was evenly distributed between LDKI and non-LDKI. The average duration of the ketamine infusions was 26.8 h with the average dose being 169.9 mg. At an average of 9 months after surgery, 42% of the ketamine group and 38% of the nonketamine group stated that they had had pain on discharge. Of these patients, 30% of the ketamine group and 26% of the nonketamine group still had pain at the time of the phone call. Women in both groups had more acute and chronic pain than men. Conclusion: These results show that LDKI does not promote a decrease in long-term postoperative pain.

Ultrasound-Guided Trigger Point Injection for Serratus Anterior Muscle Pain Syndrome: Description of Technique and Case Series.

Chronic chest pain is a challenge, and serratus anterior muscle pain syndrome (SAMPS) is often overlooked. We have developed an ultrasound-guided technique for infiltrating local anesthetics and steroids in patients with SAMPS. In 8 patients, the duration of chronic pain was approximately 19 months. Three months after treatment, all patients had experienced a significant reduction in pain. Infiltration for SAMPS confirms the diagnosis and provides adequate pain relief.

“CAPS” Cardiac Acute Pain Services—A Nationwide Survey From Canada

OBJECTIVES Acute Pain Services (APS) are well-established worldwide; however, their availability and use in cardiac surgery units are less widespread and, even where present, may be provided less consistently. The authors undertook this survey to assess the current organization of Cardiac Acute Pain Services (CAPS) in Canada. DESIGN This was a prospectively administered survey. SETTING This study included all centers in Canada that conducted adult cardiac surgery. PARTICIPANTS The participants were anesthesiologists. INTERVENTION A 20-item questionnaire covered the demographics, functioning and APS structure. RESULTS The authors achieved a response rate of 100% with completed questionnaires from all 31 centers. Ten centers (32.3%) stated that they had a dedicated CAPS, 9 centers (29%) stated that they did not have an APS, and 12 centers (38.7%) had APS but no CAPS. At the time of the survey for the 10 centers with CAPS, 3 of the CAPS had a physician-run model, 4 had a combined physician and nurse service, and 1 used a combination of protocols, intensivists, and nurse practitioners. Nine centers had an anesthesiologist assigned to daily acute pain rounds. Only in 2 of 10 centers with CAPS were more than 50% of their cardiac surgery patients receiving care. In general, postoperative pain management was a protocol-driven activity. CONCLUSIONS CAPS are varied in both structure and functioning. Further work is required both at the institutional and the national levels to improve the postoperative care and the pain-related outcomes of patients undergoing cardiac surgery.

Perioperative Right Ventricular Pressure Monitoring in Cardiac Surgery

Right ventricular (RV) dysfunction is a cause of increased morbidity and mortality in both cardiac surgery and noncardiac surgery and in the intensive care unit. Early diagnosis of this condition still poses a challenge. The diagnosis of RV dysfunction traditionally is based on a combination of echocardiography, hemodynamic measurements, and clinical symptoms. This review describes the method of using RV pressure waveform analysis to diagnose and grade the severity of RV dysfunction. The authors describe the technique, optimal use, and pitfalls of this method, which has been used at the Montreal Heart Institute since 2002, and review the current literature on this method. The RV pressure waveform is obtained using a pulmonary artery catheter with the capability of measuring RV pressure by connecting a pressure transducer to the pacemaker port. The authors describe how RV pressure waveform analysis can facilitate the diagnosis of systolic and diastolic RV dysfunction, the evaluation of RV-arterial coupling, and help diagnose RV outflow tract obstruction. RV pressure waveform analysis also can be used to guide pharmacologic treatment and fluid resuscitation strategies for RV dysfunction.