Marc J. Popovich

A prospective observational study of the effect of penicillin skin testing on antibiotic use in the intensive care unit

BACKGROUND Patients with penicillin allergy admitted to the intensive care unit (ICU) frequently receive non-beta-lactam antimicrobials for the treatment of infection. The use of these antimicrobials, more commonly vancomycin and fluoroquinolones, is associated with the emergence of multidrug-resistant infections. The penicillin skin test (PST) can help detect patients at risk of developing an immediate allergic reaction to penicillin and those patients with a negative PST may be able to use a penicillin antibiotic safely. METHODS We determined the incidence of true penicillin allergy, the percentage of patients changed to a beta-lactam antimicrobial when the test was negative, the safety of the test, and the safety of administration of beta-lactam antimicrobials in patients with a negative test. Skin testing was performed using standard methodology. RESULTS One hundred patients admitted to 4 ICUs were prospectively studied; 58 of them were male. The mean age was 63 years. Ninety-six patients had the PST: one was positive (1.04%), 10 (10.4%) were nondiagnostic, and 85 (88.5%) were negative. Of the 38 patients who received antimicrobials for therapeutic reasons, 31(81.5%) had the antibiotic changed to a beta-lactam antimicrobial after a negative reading versus 7 patients of the 57 (12%) who had received a prophylactic antimicrobial (P < .001). No adverse effects were reported after the PST or after antimicrobial administration. CONCLUSIONS The PST is a safe, reliable, and effective strategy to reduce the use of non-beta-lactam antimicrobials in patients who are labeled as penicillin allergic and admitted to the ICU.

Postoperative jejunal feeding and outcome of pancreaticoduodenectomy

Complications following pancreaticoduodenectomy are common, partly because of nutritional debilitation. The aim of this study was to evaluate the impact of early postoperative tube feeding on outcome of pancreaticoduodenectomy and determine the best method for delivering enteral feeding. A retrospective review of 180 consecutive patients undergoing Whipple operations from 1994 to 2000 was performed. Two nonrandomized patient groups were retrospectively studied: those with early postoperative tube feeding vs. those with no planned feeding. Ninety-eight patients (54%) received postoperative jejunal feeding, whereas 82 patients (46%) did not. Jejunal feeding was delivered via a bridled nasojejunal tube in 55 patients (56%) and a gastrojejunal tube in 43 (44%). Vomiting (10% vs. 29%; P = 0.002) and use of total parenteral nutrition (6% vs. 27%; P < 0.0001) were less in the jejunal feeding group as well as rates of readmission (12% vs. 27%; P= 0.022), early (52% vs. 62%; P = 0.223) and late (12% vs. 31%, P = 0.005) complications, and infections (13% vs. 20%, P = 0.014). Tube-related complications occurred in 6 of 98 patients, all of which were associated with gastrojejunal tubes (P = 0.021). Early postoperative tube feeding after pancreaticoduodenectomy is associated with significantly less use of total parenteral nutrition and lower rates of readmission and complications. A bridled nasojejunal feeding tube appears to be a safe and reliable method of short-term enteral feeding.

Predicting Immunosuppressant Dosing in the Early Postoperative Period with Noninvasive Indocyanine Green Elimination Following Orthotopic Liver Transplantation

Twenty adult patients undergoing orthotopic liver transplantation (OLT) were enrolled in this study, with the noninvasive indocyanine green plasma disappearance rate (ICG‐PDR) measured both during and after OLT to assess the relationship between ICG‐PDR and the ability of patients to achieve therapeutic postoperative tacrolimus immunosuppressant blood levels. Liver function was determined at both 2 and 18 hours post reperfusion with the ICG‐PDR k value (1/min). Postoperative standard serum measures of liver function as well as liver biopsies were also collected and analyzed. The median ICG‐PDR k value for the study group at 2 hours post reperfusion was 0.20 (0.16, 0.27), whereas at 18 hours post reperfusion, it was 0.22 (0.18, 0.35). The median change in the k value between the two ICG‐PDR measurements was 0.05 (−0.02, 0.07) with P = 0.02. There was an interaction between the postoperative day 1 (18 hours post reperfusion) ICG‐PDR k value and the linear increase in the tacrolimus blood level, such that the greater the k value was, the more gradual the observed rise was in tacrolimus over time [that is, the longer it took to achieve a therapeutic blood level (>12 ng/mL), P = 0.003]. Of the 16 patients that received tacrolimus, comparable dosing on a per kilogram body weight basis was observed. Also, no significant association between ICG‐PDR k values and postoperative liver biopsy results was seen. This study demonstrates that the ICG‐PDR measurement is a modality with the potential to assist in achieving adequate blood levels of tacrolimus following OLT. Liver Transpl 14:46–52, 2008.

Therapeutic Whole-Lung Lavage for Pulmonary Alveolar Proteinosis: A Procedural Update.

Pulmonary alveolar proteinosis is a disease caused by increased accumulation and impaired clearance of surfactant by alveolar macrophages. This narrative review summarizes the role of therapeutic whole-lung lavage in the management of pulmonary alveolar proteinosis. We describe the preprocedural evaluation, indications, and anesthetic considerations, along with step-by step technical aspects of the procedure, postoperative recovery, potential complications, and long-term outcomes.

Drug-induced immune-mediated thrombocytopenia in the intensive care unit.

A 62-year-old woman with prosthetic mitral valve was admitted for explant of an infected prosthetic knee. Perioperatively, she was bridged with heparin and started on empiric vancomycin and piperacillin-tazobactam. Platelet counts dropped precipitously within 2 days reaching a nadir of 6000/μL, without any bleeding. Decline persisted despite substituting heparin with bivalirudin. Antiplatelet factor 4 and anti-PLA1 antigen were negative. Schistocytes were absent. Antibiotics were substituted with daptomycin for suspected drug-induced thrombocytopenia. Pulse dose of intravenous immunoglobulin was initiated with rapid normalization of platelet count. She tested positive for IgG antiplatelet antibodies to vancomycin and piperacillin-tazobactam thereby confirming the diagnosis. Drug-induced immune-mediated thrombocytopenia is an underrecognized cause of thrombocytopenia in the intensive care units. Clinicians should be cognizant of this entity, and a definitive diagnosis should be sought if feasible.

Ultrasound-guided vascular access in critical care: can a choice of real-time imaging axis view overcome the "curse of dimensionality"?

920 www.ccmjournal.org April 2015 • Volume 43 • Number 4 coping behaviors uncovered by the authors should, however, be viewed with caution. First of all, it is unclear how the study investigators determined whether certain behaviors were maladaptive or constructive, and it appears that this was exclusively based on study participants’ own perceptions. Whether the behaviors described actually led to less moral distress in the long run is unclear and for some may be questionable. In light of the discussion around in-group versus out-group conflicts, “venting” to members of the same profession may enhance negative perceptions of the out-group by the in-group. Similarly, building team cohesion will only be effective if this is targeted at the entire team, not just one group within the team. If such team building is targeted at nurses only, for example, excluding the physicians (who, tellingly, did not mention this strategy as a coping behavior), it may strengthen the sense that the nursing team, the in-group, is “okay” but make the contrast with the physician team, the out-group, that is “not okay,” even starker. If we want to decrease moral distress, team building activities need to encourage affective perspective taking strategies between individuals and professional and disciplinary groups and emphasize the common goals and shared values for the whole team, encouraging team members to self-categorize primarily with the overall team rather than a subgroup that is in conflict with other subgroups.

Postoperative adverse effects after recent or remote lithium therapy.

Patients receiving preoperative lithium therapy for bipolar disorder may present unique challenges in the perioperative period and during critical illness. Two cases of critically ill patients who developed lithium-induced adverse reactions in the perioperative period due to the low therapeutic index are reported.

Use of propofol to control refractory involuntary movements

The authors report the first case of propofol use for the control of non-epileptic involuntary movements in a patient with postviral encephalitis. The withdrawal from propofol was associated with re-emergence of involuntary movements. The patient was maintained on propofol infusion for 6 months while a series of medications were used in an attempt to control the movements. The movements were finally controlled with high doses of phenobarbital, diazepam, and olanzapine, and the propofol was slowly weaned.

Incidental discovery of a partial anomalous pulmonary venous connection in the surgical critical care unit

Routine chest roentgenogram to confirm catheter placement in a postsurgical patient showed a left-sided internal jugular central venous catheter that did not appear to cross the midline. Arterial blood gas samples showed greater oxygenation from the central catheter as compared with the peripheral arterial sample. However, a transduced waveform showed a venous tracing and pressure. Computed tomographic scan of the thorax without intravenous contrast showed a partial anomalous pulmonary venous connection with drainage of the left upper lobe pulmonary vein into the innominate vein.

Bioavailability or just availability? How the national propofol shortage example may transform tenets of critical care management.

F or generations, clinical pharmacology in critical care centered on the idea that drugs were chosen for a certain condition or indication relative to their efficacy, pharmacodynamics, pharmacokinetics, bioavailability, or actions on distinct receptors. Most critical care physicians likely have vivid recollections of their formative years when learned mentors would insist, in painstaking detail, that a specific vasoactive agent was better at generating a desired effect because of a certain pharmacologic principle or property. However, in this decade, the ostensible epidemic of shortages of various drugs that are fundamental in our profession are forcing 21st-century clinicians to choose a particular medicament simply because it is the only one available. In just this year alone, critical care practitioners have seen shortages in the vital life-sustaining pharmacologic vasoactives (e.g., norepinephrine, phenylephrine, vasopressin, nitroglycerin), intravenous phosphate electrolyte replacements as well as sedatives, analgesics, and neuromuscular blockers (1). Drug shortages on this nonexhaustive list occur for a multitude of reasons, including manufacturing difficulties, quality control issues, and the realities of marketplace de-emphasis of off-patent pharmaceuticals (2, 3). Interestingly, despite traditional cogitation, discussion, and dogmatic pedantics about whether one medication is better than another for a clinical situation, it may end up that in many cases it does not really make that big of a difference after all. In this issue of Critical Care Medicine, Roberts et al (4) report their findings on whether the recent national shortage of propofol had any impact on the duration of mechanical ventilation. In a single-academic-center retrospective analysis of 281 intensive care unit patients mechanically ventilated for 48 hrs and receiving continuously infused sedatives for intensive care unit care 24 hrs, a cohort of 153 patients before the national propofol shortage were compared with 128 patients after the shortage relative to sedative choices and ventilation strategies (4). The number of patients receiving 24 hrs of propofol in the after-group was 84% less than in the before-group. Although in an unadjusted analysis there was a statistical prolongation of mechanical ventilation in the after-group, when subjected to a multivariable linear regression, only admission to a medical service, severity of illness as measured by Acute Physiology and Chronic Health Evaluation II score (5), and use of pressure-controlled ventilation achieved a statistical difference between groups (4). Propofol has been available as a sedative for intensive care unit patients since the mid-1990s. Although there are rare side effects (6), for the most part, propofol has achieved arguably a canonical status in critical care for its titratability, short half-life, and overall efficacy. Thus, when the drug suddenly becomes unavailable, there are concerns that substantial detriments in patient care may result. As the study by Cooper et al (4) demonstrated, not only was there a statistically significant increase in infusions of longer-acting sedatives (e.g., lorazepam, midazolam), but also a significantly higher use of neuromuscular-blocking infusions (4). That the use of these alternative agents did not result in statistical lengthening of mechanical ventilation is a testament to the importance of flexibility and adaptability in the overall care process, clearly clinical behaviors adjusted at a multidisciplinary level to otherwise offset the expected effect. Will the findings in the current study, coupled with continued ongoing shortages of other drugs, lead to further experimental reassessments of long-held tenets that currently guide clinical decisionmaking? Historically, dogmatic beliefs are hard to change, even with evidence-based substantiation to the contrary. Consider the example of a study published over 20 yrs ago by Cooper et al (7), which demonstrated in a prospective, randomized, blinded, crossover trial that correction of acidemia using bicarbonate vs. saline in vasopressordependent critically ill patients with lactic acidosis did not improve hemodynamics. Although the study categorically shattered the long-held notion that acidemic conditions must be attenuated to achieve vasopressor efficacy, it is very likely that most clinicians either remain unaware or still hold to and teach others this long-held belief. The difference now, as compared with 20 yrs ago, is that physicians finding themselves in perceived untenable situations as a result of the inaccessibility of heretofore ubiquitous drugs may in fact be forced into reappraisals of clinical tenets. Indeed, such changes in pharmacologic considerations may well lead to other alterations in critical care along the “less is more” style that has befallen treatment strategies for mechanical ventilation (8), invasive monitoring (9), and gastrointestinal prophylaxis (10). On the other hand, it may be a stretch to draw transformative conclusions about patient care practices and clinical decisionmaking based on one single-center, retrospective study. The authors readily acknowledge that they cannot exclude the possibility that there were some unrecognized or unverifiable effects on mechanical ventilation duration as a result of the limitations of their investigation. In addition, the lack of standardized *See also p. 406.