Diana Altshuler

Conduction Disturbances and Ventricular Arrhythmias Associated with High-Dose Loperamide

Although loperamide has been widely used for the treatment of diarrhea, there is growing popularity over its abuse potential in alleviating opioid-withdrawal symptoms and achieving euphoria. Toxic levels of loperamide have been associated with life-threatening ventricular tachyarrhythmias and cardiac arrest. We report a case of high-dose loperamide ingestion in a patient presenting initially with unstable bradycardia followed by episodes of polymorphic ventricular tachycardia, and an unmasked Brugada ECG pattern. This is the first such report of the Brugada pattern being unmasked on ECG with loperamide ingestion. The patient stabilized with supportive care without the need for inotropic support. We discuss potential mechanisms of toxicity leading to conduction abnormalities and provide a literature review of all published cases of loperamide toxicity to describe proposed treatment options. Recognition of the abuse potential and hazards of this over-the-counter anti-diarrheal therapy will alert the clinician of associated toxidromes and management strategies.

Safety of the Peripheral Administration of Vasopressor Agents

Vasopressors are an integral component of the management of septic shock and are traditionally given via a central venous catheter (CVC) due to the risk of tissue injury and necrosis if extravasated. However, the need for a CVC for the management of septic shock has been questioned, and the risk of extravasation and incidence of severe injury when vasopressors are given via a peripheral venous line (PVL) remains poorly defined. We performed a retrospective chart review of 202 patients who received vasopressors through a PVL. The objective was to describe the vasopressors administered peripherally, PVL size and location, the incidence of extravasation events, and the management of extravasation events. The primary vasopressors used were norepinephrine and phenylephrine. The most common PVL sites used were the forearm and antecubital fossa. The incidence of extravasation was 4%. All of the events were managed conservatively; none required an antidote or surgical management. Vasopressors were restarted at another peripheral site in 88% of the events. The incidence of extravasation was similar to prior studies. The use of a PVL for administration of vasopressors can be considered in patients with a contraindication to a CVC.

Methylnaltrexone Versus Naloxone for Opioid-Induced Constipation in the Medical Intensive Care Unit

Background: Opioid-induced constipation (OIC) is common in critically ill patients; it leads to complications that can increase hospital stay and, rarely, bowel perforation. Opioid antagonists are considered a logical approach to treat OIC; however, the agent of choice has yet to be determined. Objective: To assess the effectiveness and safety of enteral naloxone (NTX) versus subcutaneous methylnaltrexone (MNTX) for the treatment of OIC in the medical intensive care unit. Methods: This retrospective review evaluated patients who received fentanyl continuous infusions for at least 72 hours and were initiated on NTX or MNTX. Active colitis, mechanical gastrointestinal obstruction, and inability to receive NTX orally were exclusion criteria. The primary outcome was time to first bowel movement (BM). Secondary outcomes included total number of BMs within 48 hours, opioid requirements after NTX or MNTX, and change in any of the following after the opioid antagonist: heart rates, mean arterial pressures, and level of sedation. A post hoc subgroup analysis of patients on vasopressors was conducted. Results: Baseline characteristics were similar between patients receiving NTX (n = 52) and MNTX (n = 48), except the MNTX group required a higher median norepinephrine dose (0.22 vs 0.1 µg/kg/min, P = 0.001). The median times to first BM for NTX and MNTX were 30 and 24 hours (P = 0.165). There was no difference in the primary outcomes for patients on vasopressors. Both groups did not require additional fentanyl equivalents, as evidenced by stable vitals and opioid requirements during treatment. Conclusions: Both agents appear to be effective and safe for the treatment of OIC; however, future controlled prospective trials are warranted.

The Unsung Hero: Role of Thiamine in the ‘Vitamin C Cocktail’

To the Editor: The study by Marik and colleagues, published in the June issue of CHEST, is thought-provoking and exciting. Combining intravenous vitamin C with corticosteroids and thiamine reduced mortality by 31.9% in a beforeand-after cohort. This research has sparked much interest and debate regarding the efficacy of this “cocktail,” with the majority of focus placed on the vitamin C component. The effects of corticosteroids in sepsis have long been discussed and debated, and the potential synergism between corticosteroids and vitamin C is interesting. However, we believe that the contribution of thiamine in this “cocktail” may have been underappreciated.

Venous Thromboembolism Prophylaxis: A Narrative Review With a Focus on the High-Risk Critically Ill Patient

Venous thromboembolism (VTE) is a major health concern associated with significant morbidity and mortality. Critically ill patients are at an increased risk of VTE compared to general medical patients due to unique risk factors: prolonged immobilization, invasive lines and devices, certain medications, and acquired thrombophilia. Furthermore, VTE in the critically ill is associated with increased duration of mechanical ventilation, increased length of intensive care unit and hospital stay, and a trend toward increased mortality. Clinical practice guidelines therefore recommend VTE prophylaxis with either subcutaneous heparin or low-molecular-weight heparin for all critically ill patients without contraindication. Yet, many patients will develop VTE despite appropriate pharmacologic prophylaxis, which has led to interest in risk-stratifying critically ill patients for more aggressive prophylaxis strategies. Recent research identified patients at highest risk of failure of thromboprophylaxis and provided insight into the pathophysiologic mechanisms. Obesity and the receipt of vasopressors are 2 risk factors consistently identified in observational studies; further clinical data support decreased absorption of anticoagulant administered via the subcutaneous route as the likely mechanism behind thromboprophylaxis failure in these patient populations. Several studies have investigated novel thromboprophylaxis strategies to circumvent pharmacokinetic limitations in patients who are obese or on vasopressors: increased fixed-dose, weight-based subcutaneous, or continuous intravenous infusion of a prophylactic dose of anticoagulant has shown promise in limited studies; however, the results have yet to demonstrate superiority compared to current standard-of-care. This review discusses observational studies identifying patients at risk of thromboprophylaxis failure and critiques clinical studies evaluating novel thromboprophylaxis strategies in high-risk, critically ill patients with a focus on their limitations. Future studies are currently being conducted that will provide further guidance into the appropriate use of individualized thromboprophylaxis.

Incidence of Adverse Events During Peripheral Administration of Sodium Chloride 3

Purpose: Traditionally, sodium chloride 3% has been administered via a central venous line (CVL) because of the perceived risk of infiltration and tissue injury due to its high osmolarity. In clinical practice, sodium chloride 3% is commonly administered through peripheral venous catheters (PVCs) given the necessity of timely administration. However, there is no published data on the safety of administering sodium chloride 3% through PVCs in the adult population. The objective of this study was to evaluate the safety of peripheral venous administration of sodium chloride 3%. Materials and Methods: A retrospective review was conducted in patients who received sodium chloride 3% in the intensive care unit (ICU). Patients were excluded if they had a CVL for the entire duration of the infusion or younger than 18 years at the time of administration. Baseline patient and infusion characteristics were collected. Infusion-related adverse events (IRAEs) were recorded, graded, and interventions required were noted. Results: A total of 66 patients were included in the analysis. The most common indication was hyponatremia and majority of the patients were managed in the neurosurgical ICU. The most common risk factor for IRAEs was the presence of altered mental status. Four patients experienced an IRAE at an event rate of 6.1%. Patients who experienced an IRAE ranged from 38 to 82 years old. The IRAEs were grade 1 in severity, managed conservatively with removal of the PVC, and 2 of the 4 patients had their infusions restarted peripherally. The time to initial IRAE ranged from 2 to 94 hours. For the entire cohort, hospital and ICU length of stay were 8 and 4 days, respectively. Conclusions: The rate of IRAEs related to the infusion of sodium chloride 3% through PVCs appears to be similar to those reported with other hyperosmotic agents and could be considered for patients who need time-sensitive therapy.

Major publications in the critical care pharmacotherapy literature: January–December 2016

Purpose: To summarize select critical care pharmacotherapy guidelines and studies published in 2016. Summary: The Critical Care Pharmacotherapy Literature Update (CCPLU) Group screened 31 journals monthly for relevant pharmacotherapy articles and selected 107 articles for review over the course of 2016. Of those included in the monthly CCPLU, three guidelines and seven primary literature studies are reviewed here. The guideline updates included are as follows: hospital‐acquired pneumonia and ventilator‐associated pneumonia management, sustained neuromuscular blocking agent use, and reversal of antithrombotics in intracranial hemorrhage (ICH). The primary literature summaries evaluate the following: dexmedetomidine for delirium prevention in post‐cardiac surgery, dexmedetomidine for delirium management in mechanically ventilated patients, high‐dose epoetin alfa after out‐of‐hospital cardiac arrest, ideal blood pressure targets in ICH, hydrocortisone in severe sepsis, procalcitonin‐guided antibiotic de‐escalation, and empiric micafungin therapy. Conclusion: The review provides a synopsis of select pharmacotherapy publications in 2016 applicable to clinical practice. Highlights:Reviews pharmacotherapy‐focused guidelines (n = 3) and studies (n = 7)Articles selected based on applicability, relevance, and strength of study designCommentary provided by critical care pharmacists on clinical impact

Evaluating Vasopressor Discontinuation Strategies in Patients With Septic Shock on Concomitant Norepinephrine and Vasopressin Infusions

Background: There is little data guiding clinicians on how to discontinue vasopressors among septic shock patients on concomitant norepinephrine (NE) and vasopressin (VP). Objective: To determine the incidence of hypotension within 24 hours of discontinuing NE (NE DC first) versus VP (VP DC first) first in septic shock patients. Methods: This retrospective study evaluated septic shock patients admitted to the medical intensive care unit (MICU) and surgical ICU (SICU) receiving concomitant NE and VP. Receipt of additional vasopressors, mixed shock states, expired or care withdrawn, and NE and VP discontinued simultaneously were exclusion criteria. The primary outcome was incidence of hypotension within 24 hours of first vasopressor discontinuation. Secondary outcomes included time to hypotension, hospital length of stay (LOS), ICU LOS, and ICU mortality. Results: A total of 80 patients were included (NE DC first [n = 35]; VP DC first [n = 45]), with a median age of 73 years and median modified Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores of 21 and 7, respectively. More patients in the NE DC first group were in the SICU (42.9% vs 20.0%; P = 0.048) with more intra-abdominal infections (40.0% vs 15.6%; P = 0.021) and fewer appropriate empirical antibiotics (62.9% vs 86.7%; P = 0.018). Hypotension within 24 hours of first agent discontinuation was higher in the VP DC first group (28.6% vs 62.2%; P = 0.004), with similar hospital LOS and ICU mortality. Multivariate analysis identified VP DC first as an independent predictor of hypotension (odds ratio = 7.2; CI = 2.3-22.7). Conclusion: Among septic shock patients on concomitant NE and VP, discontinuation of VP first was associated with an increased incidence of hypotension; future prospective control trials are warranted.

Evaluation of Pharmacy-Developed Antibiotic Desensitization Protocols

Background: Parameters within reconstitution, storage, stability, and administration may be optimized according to the unique pharmacokinetics of each antibiotic to ensure a successful desensitization. Objective: The study aims to evaluate the successfulness and safety of antibiotic desensitization protocols developed by the pharmacy department at our institution. Methods: A retrospective study was conducted at an 800-bed, urban, tertiary care, academic medical center. A total of 36 patients 18 years of age or older, admitted to our intensive care units between March 2013 and July 2017, who underwent antibiotic desensitization utilizing our pharmacy developed protocols were included. Results: In 36 patients, 61 desensitization cases were identified and included; 17 (47%) were male, 27 (75%) were Caucasian, and the median age was 55 years (range 19-94). In all, 15 different antibiotics were administered for desensitization, with meropenem (n = 12, 20%), ampicillin (n = 7, 11%), piperacillin/tazobactam (n = 7, 11%), and penicillin (n = 7, 11%) being the most common; 59 (97%) of 61 desensitizations were completed successfully with or without experiencing reactions, and 53 (89%) of the successful desensitization cases were completed without reactions. Two cases were categorized as anaphylaxis, which was severe enough to terminate the desensitization process. Of the 59 cases successfully completed, the 6 (10%) cases that experienced reactions were managed successfully during desensitization with completion of the process. Conclusion and Relevance: The findings suggest that our pharmacy-developed antibiotic desensitization protocols are successful and safe and may be adapted by other institutions.

Tigecycline as a Second-Line Agent for Legionnaires’ Disease in Severely Ill Patients

Abstract Treatment of Legionnaires’ disease in severely ill or immunosuppressed patients presents a clinical challenge. Tigecycline (TG) achieves high concentrations intracellularly and has been shown to be effective against L. pneumophila in animal and cell models. We report our experience using TG as second-line therapy. Clinical response was seen in most patients after switching to TG alone or as a combination therapy.