HPXXXX10.1177/0018578719867646Hospital PharmacyBuckley et al 867646research-article2019 Original Article Hospital Pharmacy 1 –7 Analysis of Vasopressor Discontinuation © The Author(s) 2019 Article reuse guidelines: sagepub.com/journals-permissions and the Incidence of Rebound DOI:https://doi.org/10.1177/0018578719867646 10.1177/0018578719867646 Hypotension in Patients With Septic journals.sagepub.com/home/hpx Shock Christopher T. Buckley1 , Ben Turner2, Dalton Walsh2, Meghan J. Garrett2, and Vishal N. Ooka3 Abstract Purpose: The purpose of this study was to examine the incidence of rebound hypotension in patients with septic shock requiring both norepinephrine and vasopressin infusions once discontinuation of 1 of these agents is warranted. Methods: A multicenter, retrospective study was conducted in 3 hospitals within a single health system between January 1, 2016, and December 31, 2017. The study population included adults, 18 years and older, diagnosed with septic shock and requiring concurrent infusions of norepinephrine and vasopressin. The primary outcome evaluated the incidence of rebound hypotension within 24 hours after the first vasopressor was discontinued. Secondary outcomes included intensive care unit length of stay, hospital length of stay, total vasopressor duration, and the time to rebound hypotension after first vasopressor discontinuation. Results: A total of 69 patients were included in the study, 38 in the vasopressin discontinued first group and 31 in the norepinephrine discontinued first group. Rebound hypotension occurred in 82% of patients in the vasopressin discontinued first group compared with 48% in the norepinephrine discontinued first group (P = .004). No differences were observed in secondary outcomes, including intensive care unit or hospital length of stay, total vasopressor duration, or the time to rebound hypotension. Conclusions: Discontinuation of norepinephrine before vasopressin may lead to less incidence of rebound hypotension in patients with septic shock who require concurrent norepinephrine and vasopressin infusions. Similar to previous studies, this study found no difference in secondary outcomes. Keywords cardiac agents, cardiovascular, critical care Background provides inotropic effect via cardiac β receptors and pro- duces vasoconstriction through stimulation of α-receptors in Sepsis is defined as life-threatening organ dysfunction the peripheral vasculature. Vasopressin is an endogenous caused by a dysregulated host response to infection. Septic hormone synthesized in the hypothalamus and released from shock, a subset of sepsis, includes underlying circulatory and the posterior pituitary gland. The mechanism of interest in cellular/metabolic abnormalities that have mortality rates in patients with septic shock is stimulation of V1 receptors in excess of 40%. Per the Third International Consensus vascular smooth muscle, which mediates vasoconstriction Definition for Sepsis and Septic Shock (Sepsis-3), patients via influx of intracellular calcium.4,5 Vasopressin is often the with septic shock are classified as having sepsis with persis- second agent added to patients with septic shock based on tent hypotension, defined as mean arterial pressure (MAP) this alternative mechanism of action and results of the less than 65 mm Hg despite adequate fluid resuscitation; Vasopressin and Septic Shock Trial (VASST) trial. Although requiring vasopressors; and having a serum lactate greater the VASST trial found no difference in mortality with the than 2 mmol/L.1 The systemic vasodilation and cardiac dys- function seen in septic shock lead to decreased tissue and 1 2 University of Tennessee Health Science Center, Memphis, USA organ perfusion and ultimately organ dysfunction. 2Saint Thomas Rutherford Hospital, Murfreesboro, TN, USA The 2016 Surviving Sepsis Campaign guidelines endorse 3St. Vincent Indianapolis, IN, USA norepinephrine as the first vasopressor to be used in septic Corresponding Author: shock and adding either epinephrine or vasopressin as a sec- Christopher T. Buckley, Union University College of Pharmacy, 1050 ond-line vasopressor to increase a patient’s MAP or vaso- Union University Drive, Jackson, TN 38305, USA. 3 pressin to decrease norepinephrine dose. Norepinephrine Email: [email protected] 2 Hospital Pharmacy 00(0) addition of norepinephrine or vasopressin in septic shock a set rate of 0.04 units/min and was only titratable by pro- patients already receiving norepinephrine, there was a trend vider order rather than nurse titration. toward decreased mortality in a subgroup analysis from 6 patients with less severe septic shock. Patients As stated, current guidelines recommend which vasopres- sors to initiate in patients with septic shock, but provide no Patients older than 18 years of age requiring concurrent con- guidance on the order of their discontinuation once a patient tinuous infusions of norepinephrine and vasopressin during is in the recovery phase of septic shock.3 As a general defini- the defined study period were included. Patients were tion, the recovery phase is when vasopressors are able to be excluded if they were not diagnosed with sepsis or septic weaned due to normalization of cardiac function and vascu- shock; if norepinephrine and vasopressin were discontinued lar tone. The lack of recommendation has led to wide vari- at the same time; if they received additional inotropic, vaso- ability in clinical practice with some practitioners preferring pressor, or other adjuvant medications (including epineph- to discontinue vasopressin first because of limited data for rine, phenylephrine, dopamine, dobutamine, milrinone, and vasopressin monotherapy in septic shock. Landry and col- midodrine); or if they were admitted from surgery, transi- leagues7,8 described a vasopressin deficiency in septic shock, tioned to palliative care, or expired while receiving both which could potentially influence the order in which vaso- vasopressin and norepinephrine. pressors are discontinued. This practice is further compli- cated by practitioners who elect to discontinue both agents Study Objectives simultaneously. There are few studies that compare the inci- dence of rebound hypotension after discontinuation of nor- The primary objective was to examine the incidence of epinephrine or vasopressin in septic shock patients requiring rebound hypotension within 24 hours based on the order of both agents. Available data from retrospective studies are norepinephrine or vasopressin discontinuation. The term conflicting, with 4 studies showing an increased incidence of rebound hypotension was used, as hypotension is a potential hypotension when vasopressin is discontinued first, but the consequence vasopressor discontinuation. Rebound hypo- largest study (n = 585) showing no difference between tension was defined as a composite of (1) 2 consecutive groups.9-13 A small prospective study (n = 78), also looking MAP readings of <60 mm Hg, (2) crystalloid fluid bolus at hypotension after vasopressor discontinuation, was administration > 500 mL, (3) increasing the dose of norepi- stopped early due to a significant increase in hypotension nephrine by 25% after vasopressin discontinuation, or (4) re- when norepinephrine was discontinued first.14 Finally, a initiation of norepinephrine after it was discontinued. recently published individual patient data meta-analysis, Because the third and fourth criteria are solely dependent on which included the previously mentioned studies (n = 957), the order of vasopressor discontinuation, these will be found hypotension to occur more often when vasopressin reported as norepinephrine response to rebound hypotension. was discontinued first.15 Multiple criteria could occur, but only 1 criterion was needed The purpose of this study was to examine the incidence of to give rise to the composite of rebound hypotension. rebound hypotension in patients with septic shock requiring Secondary objectives included the time to rebound hypoten- both norepinephrine and vasopressin infusions once discon- sion after first vasopressor discontinuation, total duration of tinuation of 1 of these agents is warranted. vasopressors, and both ICU and hospital length of stay. Methods Data Collection Study Design Baseline demographics collected include age, sex, race, weight, and comorbidities. Additional data collected from This was a multicenter, retrospective study of 69 patients the electronic medical record include infection source, con- admitted to the intensive care unit (ICU) of 3 hospitals within comitant therapies that may affect patients’ hemodynamics a health system between January 2016 and December 2017. (such as hydrocortisone, mechanical ventilation, hemodialy- The study protocol was approved by Sterling Institutional sis, and propofol use) and vasopressor duration. Review Board, and a waiver of informed consent was granted due to the retrospective nature of the study. A report was gen- Statistical Analysis erated to identify patients receiving vasopressin during the study timeframe. There was no protocol or guideline for any Statistics were performed using IBM SPSS Statistics. vasopressor weaning or discontinuation for patients with Categorical variables were analyzed using Fisher exact tests septic shock at any institution during the study period, and or Pearson χ2 as appropriate. Continuous data were analyzed thus, the decision was left to the discretion of the providers. using Mann-Whitney U test with data presented as median Norepinephrine was infused in micrograms