A survey of acute pain service in Canadian teaching hospitals.

BACKGROUND: The first national survey to ascertain the prevalence, structure, and functioning of the APS in Canadian university affiliated hospitals was conducted in 1991. This is a follow-up survey to assess the current status of the APS in Canada. METHODS: We requested completion of a 26-question survey from lead personnel of the APS teams or Anesthesia departments of Canadian teaching hospitals. RESULTS: Among the 32 centers that were contacted, 21 (65.6%) responded. Of these respondents, 18 (85.7%) indicated that they have a structured APS (72.22% adults, 5.56% pediatrics, 22.22% mixed). Among the 18 centers with an APS, 16 of the services are led by an anesthesiologist. Eight centers (44.44%) have a regional anesthesia group, of which five (27.75%) have a regional anesthesia group that is distinct from the APS team. Nine centers (50%) offer ambulatory nerve catheter analgesia after discharge home. Fifteen centers (83.33%) use standardized order sets, and 13 centers (72.22%) use an electronic record for APS. More than 50% of the centers use intravenous lidocaine and ketamine as a part of their multimodal analgesia. CONCLUSION: Most Canadian teaching hospitals do have a functioning APS. This survey has the potential to generate research questions about the availability of standardized and advanced acute pain management in Canada's teaching hospitals.

Methadone for Pain Management: A Pharmacotherapeutic Review.

Methadone is increasingly being used for its analgesic properties. Despite the increasing popularity, many healthcare providers are not familiar with methadone's complex pharmacology and best practices surrounding its use. The purpose of this narrative review article is to discuss the pharmacology of methadone, the evidence surrounding methadone's use in acute pain management and both chronic cancer and non-cancer pain settings, as well as highlight pertinent safety, monitoring, and opioid rotation considerations. Methadone has a unique mechanism of action when compared with all other opioids and for this reason methadone has come to hold a niche role in the management of opioid-induced hyperalgesia and central sensitization. Understanding of the mechanisms of variability in methadone disposition and drug interactions has evolved over the years, with the latest evidence revealing that CYP 2B6 is the major determinant of methadone elimination and plays a key role in methadone-related drug interactions. From an acute pain perspective, most studies evaluating the use of intraoperative intravenous methadone have reported lower pain scores and post-operative opioid requirements. Oral methadone is predominantly used as a second-line opioid treatment for select chronic pain conditions. As a result, several oral morphine to oral methadone conversion ratios have been proposed, as have methods in which to rotate to methadone. From an efficacy standpoint, limited literature exists regarding the effectiveness of methadone in the chronic pain setting with most of the available efficacy data pertaining to methadone's use in the treatment of cancer pain. Many of the prospective studies that exist feature low participant numbers. Few clinical trials investigating the role of methadone as an analgesic treatment are currently underway. The complicated pharmacokinetic properties of methadone and risks of harm associated with this drug highlight how critically important it is that healthcare providers understand these features before prescribing/dispensing methadone. Particular caution is required when converting patients from other opioids to methadone and for this reason only experienced healthcare providers should undertake such a task. Further randomized trials with larger sample sizes are needed to better define the effective and safe use of methadone for pain management.

Expanding Role of NMDA Receptor Antagonists in the Management of Pain.

Pain management is complex regardless of whether the pain is acute or chronic in nature or non-cancer or cancer related. In addition, relatively few pain pharmacotherapy options with adequate efficacy and safety data currently exist. Consequently, interest in the role of NMDA receptor antagonists as a pharmacological pain management strategy has surfaced. This narrative review provides an overview of the NMDA receptor and elaborates on the pharmacotherapeutic profile and pain management literature findings for the following NMDA receptor antagonists: ketamine, memantine, dextromethorphan, and magnesium. The literature on this topic is characterized by small studies, many of which exhibit methodological flaws. To date, ketamine is the most studied NMDA receptor antagonist for both acute and chronic pain management. Although further research about NMDA receptor antagonists for analgesia is needed and the optimal dosage/administration regimens for these drugs have yet to be determined, ketamine appears to hold the most promise and may be of particular value in the perioperative pain management realm.

Pain and Surgical Outcomes Reporting After Laparoscopic Ventral Hernia Repair in Relation to Mesh Fixation Technique: A Systematic Review and Meta-Analysis of Randomized Clinical Trials.

OBJECTIVES: The aim of this meta-analysis was to examine postoperative pain and surgical outcomes (operative time, hospital stay, the incidence of seroma and recurrence) with different mesh fixation methods following laparoscopic ventral hernia repair (LVHR). METHODS: Randomized clinical trials compared different methods of mesh fixation in LVHR and reported on pain outcome measures analyzed. The results were expressed as odds ratio (OR) for combined dichotomous and mean difference (MD) for continuous data. RESULTS: Five randomized controlled trials (RCTs) with a total of 466 patients comparing tack mesh fixation to suture mesh fixation technique in LVHR were identified, all were published after 2005. A meta-analysis gave statistically similar odds of postoperative chronic pain (OR, 1.24; 95% CI, 0.65-2.38; z = 0.65; P = .51). No difference in pain intensity (PI) scores was found at 4-6 weeks (MD, 0.18;% CI, -0.48 to 0.85; z = 0.54; P = .59) and at 3-6 months postoperatively (MD, 0.10; 95% CI, -0.21 to 0.42; z = 0.64; P = .52). There was no difference in the pooled analysis of seroma/hematoma formation (OR, 0.60; 95% CI, 0.29-1.26; z = 1.35; P = .18), recurrence (OR, 1.11; 95% CI, 0.34-3.62; z = 0.18; P = .86), and hospital stay (MD, -0.06; 95% CI, -0.19 to 0.08; z = 0.83; P = .40). Operative time was significantly lower with tack fixation (MD, -19.25; 95% CI, -27.98 to -10.51; z = 4.32; P < .05). CONCLUSIONS: Meta-analysis of RCTs comparing tacks to suture fixation in LVHR showed comparable results with regard to postoperative chronic pain incidence and PI, and hernia recurrence. However, the operative time is shorter with tacks compared to suture fixation technique.

Postoperative pain management in patients with chronic kidney disease.

Chronic kidney disease (CKD) is a health care problem with increasing prevalence worldwide. Pain management represents one of the challenges in providing perioperative care for this group of patients. Physicians from different specialties may be involved in pain management of CKD patients, especially in advanced stages. It is important to understand the clinical staging of kidney function in CKD patients as the pharmacotherapeutic pain management strategies change as kidney function becomes progressively impaired. Special emphasis should be placed on dose adjustment of certain analgesics as well as prevention of further deterioration of renal function that could be induced by certain classes of analgesics. Chronic pain is a common finding in CKD patients which may be caused by the primary disease that led to kidney damage or can be a direct result of CKD and hemodialysis. The presence of chronic pain in some of the CKD patients makes postoperative pain management in these patients more challenging. This review focuses on the plans and challenges of postoperative pain management for patient at different stages of CKD undergoing surgical intervention to provide optimum pain control for this patient population. Further clinical studies are required to address the optimal medication regimen for postoperative pain management in the different stages of CKD.

Obstetric anesthesia considerations in Kearns-Sayre syndrome: a case report.

Kearns-Sayre syndrome (KSS) is a rare mitochondrial myopathy that usually develops before 20 years of age. It demonstrates multisystemic involvement with a triad of cardinal features: progressive ophthalmoplegia, pigmentary retinopathy, and cardiac conduction abnormalities. In addition, patients might have cerebellar ataxia, a high content of protein in the cerebrospinal fluid, proximal myopathy, multiple endocrinopathies, and renal tubular acidosis. We herein report the successful obstetric analgesic and anesthetic management of a 28-year-old parturient patient with KSS who required labor analgesia and proceeded to deliver by cesarean section. We extrapolate that regional analgesia/anesthesia might be beneficial for reducing the metabolic demands associated with the stress and pain of labor in patients with KSS. Efficient postoperative analgesia should be provided to decrease oxygen requirements.

The role of a low-dose ketamine-midazolam regimen in the management of severe painful crisis in patients with sickle cell disease.

CONTEXT: Acute pain is one of the main causes of hospital admission in sickle cell disease, with variable intensity and unpredictable onset and duration. OBJECTIVES: We studied the role of a low-dose intravenous (IV) ketamine-midazolam combination in the management of severe painful sickle cell crisis. METHODS: A retrospective analysis was performed with data from nine adult patients who were admitted to the intensive care unit with severe painful sickle cell crises not responding to high doses of IV morphine and other adjuvant analgesics. A ketamine-midazolam regimen was added to the ongoing opioids as an initial bolus of ketamine 0.25mg/kg, followed by infusion of 0.2-0.25mg/kg/h. A midazolam bolus of 1mg followed by infusion of 0.5-1mg/h was added to reduce ketamine emergence reactions. Reduction in morphine daily requirements and improvement in pain scores were the determinants of ketamine-midazolam effect. The t-tests were used for statistical analysis. RESULTS: Nine patients were assessed, with mean age of 27±11 years. Morphine requirement was significantly lower after adding the IV ketamine-midazolam regimen. The mean±SD IV morphine requirement (milligram/day) in the pre-ketamine day (D0) was 145.6±16.5, and it was 112±12.2 on Day 1 (D1) of ketamine treatment (P=0.007). The Numeric Rating Scale scores on D0 ranged from eight to ten (mean 9.1), but improved to range from five to seven (mean 5.7) on D1. There was a significant improvement in pain scores after adding ketamine-midazolam regimen (P=0.01). CONCLUSION: Low-dose ketamine-midazolam IV infusion might be effective in reducing pain and opioid requirements in patients with sickle cell disease with severe painful crisis. Further controlled studies are required to prove this effect.

A review of the use of ketamine in pain management.

Ketamine is a noncompetitive antagonist of N-methyl-d-aspartate receptor. It has been widely used in anesthesia and pain management. Ketamine has been administered via the intravenous, intramuscular, subcutaneous, oral, rectal, topical, intranasal, sublingual, epidural, and caudal routes. Ketamine improves postoperative and posttrauma pain scores and reduces opioid consumption. It has special indication for patients with opioid tolerance, acute hyperalgesia, and neuropathic pain. It also has a role in the management of chronic pain including both cancer and noncancer pain. Recreational use of ketamine is increasing as well through different routes of administration like inhalation, smoking, or intravenous injection. Long-time exposure to ketamine, especially in the abusers, may lead to serious side effects. This review is trying to define the role of ketamine in pain management.

Prevention of Intra-operative Cerebral Ischemia during Carotid Endarterectomy, Loco-regional versus General Anesthesia.

Carotid endarterectomy (CEA), as a prophylactic operation is becoming more popular. It is performed in patients who are at risk of stroke from dislodged atheromatous plaque at the carotid bifurcation. The major concern during CEA is the detection of cerebral hypoperfusion or ischemia during carotid cross clamping. Some studies have shown that the introduction of loco-regional anesthesia has lowered the incidence of major complications compared with general anesthesia since ischemia detection is easier in conscious patient.

Liquid ventilation.

Mammals have lungs to breathe air and they have no gills to breath liquids. When the surface tension at the air-liquid interface of the lung increases, as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation (LV) is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen, as the inert carrier of oxygen and carbon dioxide offers a number of theoretical advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. The potential for multiple clinical applications for liquid-assisted ventilation will be clarified and optimized in future.

Complications of Central Venous Catheterisation: Breakage of guidewire-a disaster averted.

Central venous catheterisation (CVC) is a common bedside invasive procedure done in medical practice. Even though it is a safe procedure when done with ultrasound guidance, difficulties and complications do occur even in experienced hands. Here, we describe the difficulties encountered in the form of the breakage of the guidewire while inserting a CVC in a patient with sickle cell disease.

Subclavian vein injury and massive hemothorax requiring thoracotomy following insertion of tunneled dialysis catheter--a case report and review of literature.

Tunneled dialysis catheters are widely used for hemodialysis. Large caliber dilator is used for insertion of such catheter which can result in serious vascular injury leading to haemothorax. Here we report such an inadvertent central venous injury requiring thoracotomy following blind dilator advancement along with review of literature and recommendation to prevent such complication.