Cristian Merchan

Multidrug-Resistant Bacteroides fragilis Bacteremia in a US Resident: An Emerging Challenge

We describe a case of Bacteroides fragilis bacteremia associated with paraspinal and psoas abscesses in the United States. Resistance to b-lactam/b-lactamase inhibitors, carbapenems, and metronidazole was encountered despite having a recent travel history to India as the only possible risk factor for multidrug resistance. Microbiological cure was achieved with linezolid, moxifloxacin, and cefoxitin.

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.

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.

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.

Tolerability of Enteral Nutrition in Mechanically Ventilated Patients With Septic Shock Who Require Vasopressors.

Purpose: Enteral nutrition (EN) is often held in patients receiving vasopressor support for septic shock. The rationale for this practice is to avoid mesenteric ischemia. The objective of this study is to evaluate the tolerability of EN in patients with septic shock who require vasopressor support and determine factors associated with tolerance of EN. Materials and Methods: This was a single-center retrospective review of adult patients admitted to the intensive care unit with a diagnosis of septic shock and an order for EN. The primary outcome was EN tolerance. Secondary outcomes included time to initiation of EN from the start of vasopressor(s), length of stay, and mortality. Results: A total of 120 patients were included. Sixty-two percent of patients tolerated EN. The most common reason for intolerance of EN was gastric residuals > 250 mL (74%). No reports of mesenteric ischemia were observed. A multivariate analysis demonstrated that patients with septic shock initiating EN within 48 hours and receiving norepinephrine-equivalent doses of 0.14 μg/kg/min or less were more likely to tolerate EN. Conclusion: Based on our observation, early EN may be tolerated and safely administered in patients with septic shock who are adequately fluid resuscitated and receive doses of < 0.14 μg/kg/min of norepinephrine equivalents.