Grisell Vargas-Schaffer

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.

Attitudes Toward Opioids and Risk of Misuse/Abuse in Patients with Chronic Noncancer Pain Receiving Long-term Opioid Therapy

Objectives To determine the attitudes of patients toward long-term opioid therapy (LtOT) and the potential risk of misuse/abuse in patients with chronic noncancer pain (CNCP). Design Prospective, descriptive epidemiological study. Setting Multidisciplinary tertiary care pain center within the Montreal University Health Center. Subjects Patients who had had at least one visit at least one year prior to the invitation. Methods We used four questionnaires: demographic questionnaire, the Drug Attitude Inventory Modified (DAI-M), the Opioid Risk Tool (ORT), and the Screening Tool for Addiction Risk (STAR). All questionnaires were administered in their validated French version. Results Three hundred seventy patients completed questionnaires. The response rate was 79.26%. Of those who responded, 61.62% women and 38.38% men, the mean age was 57 years. The patients had been treated with LtOT for an average of 6.31 years, and the median dose per day in morphine equivalents was 48.21 mg. The DAI-M showed that 32.16% had a positive attitude toward opioids, 39.73% had a negative attitude, and 22.16% had a neutral attitude. The ORT questionnaire demonstrated that 86.2% of the patients were at low risk of abuse/misuse, 13.2% were at moderate risk, and only 0.54% were at high risk. The STAR questionnaire showed that 4.2% had a low risk of abuse/misuse. Conclusions Despite public opinion, patients treated with LtOT for CNCP and followed in a tertiary care pain center are at low risk for opioid misuse/abuse. We need to refine the way of prescribing opioids, should be selective with our patients, and should relive their pain adequately.

“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.