Haemodynamic effects of parenteral vs. enteral paracetamol in critically ill patients: a randomised controlled trial

Haemodynamic effects of intravenous acetaminophen in critically ill paediatric patients: a retrospective chart review

OBJECTIVES

Haemodynamic changes following intravenous acetaminophen are well studied in adults. Limited data are published in critically ill paediatric patients, especially from the Middle East. We aim to investigate haemodynamic effects and incidence of hypotension with intravenous acetaminophen in critically ill children, with a focus on understanding factors influencing these effects.

METHODS

We retrospectively reviewed patients who received intravenous acetaminophen between July and December 2022. A haemodynamic event was defined as drop of >15% in systolic blood pressure (SBP) or mean arterial blood pressure (MAP) within 120 min after drug administration. Hypotension was defined as either drop in SBP below the 5th percentile for age, or a haemodynamic event associated with tachycardia, increased lactate or treatment with fluid/vasopressors. Logistic regression was performed to quantify relationships between patients' characteristics and the occurrence of haemodynamic event and hypotension.

RESULTS

A haemodynamic event was observed in 50/156 patients (32%) post-acetaminophen. Mean MAP (SD) before and after acetaminophen was 69.6 mm Hg (14.8) and 67.4 mm Hg (13.9), respectively (p=0.001). Mean SBP (SD) before and after acetaminophen was 95.4 mm Hg (18.2) and 92.8 mm Hg (19.2), respectively (p=0.006). Baseline MAP, median (interquartile range (IQR)) was 76.0 (64.0-85.3) and 66.0 (57.0-74.5) in patients with and without haemodynamic events, respectively (p=0.004). Only 38/156 patients (24%) met the definition for hypotension. Baseline MAP, median (IQR) was 62.0 (51.8-79.0) in patients with, and 68.5 (62.0, 79.3) in patients without hypotension (p=0.036). Baseline shock, vasoactives, mechanical ventilation and paediatric sequential organ failure assessment were not significantly associated with hypotension. Only MAP was found to be associated with both haemodynamic event (adjusted odds ratio (AOR) 1.05, 95% CI 1.02-1.10) and hypotension (AOR 1.06, 95% CI 1.02-1.10) even after controlling for other confounders.

CONCLUSIONS

Administration of intravenous acetaminophen in critically ill children can lead to haemodynamic changes, including clinically significant hypotensive events.

The Three W's of Acetaminophen In Children: Who, Why, and Which Administration Mode

Acetaminophen is one of the oldest medications commonly administered in children. Its efficacy in treating fever and pain is well accepted among clinicians. However, the available evidence supporting the use of acetaminophen's different modes of administration remains relatively scarce and poorly known. This short report summarizes the available evidence and provides a framework to guide clinicians regarding a rational use of acetaminophen in children.

Incidence of Hemodynamic Changes Following Intravenous Acetaminophen Administration in Critically Ill Pediatric Patients

OBJECTIVE

Acetaminophen is a commonly administered analgesic and antipyretic medication that is generally well-tolerated. Recent studies in critically ill adults and subsets of pediatric patients with underlying cardiac disease identify an association between adverse hemodynamic effects with intravenous (IV) acetaminophen. However, the data may not be generalizable to a broader population of critically ill children. The objective of this study was to determine the incidence of hemodynamic changes associated with IV acetaminophen administration in critically ill pediatric medical-surgical patients.

METHODS

This was a retrospective observational study of all patients 18 years of age and younger who received at least 1 dose of IV acetaminophen in a pediatric intensive care unit at a quaternary care medical center, between July and December 2018. The primary outcome was the incidence of hypotension, defined as a decrease in mean arterial pressure (MAP) by at least 15% from baseline. Potential risk factors for IV acetaminophen-associated hypotension were assessed.

RESULTS

A total of 212 patients received 492 doses of IV acetaminophen. The primary endpoint of hypotension occurred following 24% of doses. An intervention for hypotension, primarily fluid resuscitation, was required for 11.9% of the dose-associated hypotension events. Patients receiving vasoactive infusions had more frequent dose-associated hypotension events than those not receiving infusions; however, no other potential risk factors were identified.

CONCLUSIONS

The incidence of hypotension observed in critically ill pediatric patients after IV acetaminophen administration is clinically relevant. Large placebo-controlled trial and further study of the risk factors and mechanism of this hemodynamic change are warranted.

Acetaminophen-induced hypotension in sepsis

Background

Acetaminophen-induced hypotension has been reported in critically ill patients; however, it remains unclear whether mannitol, present as a stabilizing compound in acetaminophen formulations, affects hemodynamic changes. The objectives of this study were to clarify the direct effect of acetaminophen on blood pressure by comparing blood pressure changes after acetaminophen and intravenous immunoglobulin (IVIG) administration, both containing mannitol, in patients with sepsis and understand the risk factors for reduced blood pressure following acetaminophen administration.

Methods

This was a retrospective cohort study. Adult patients who were diagnosed with sepsis at Nippon Medical School Hospital, and who were undergoing continuous arterial blood pressure measurement and received intravenous acetaminophen or IVIG, were included.

Results

Overall, 185 patients were included, with 92 patients in the IVIG group and 93 in the acetaminophen group. The incidence of hypotension was 36.9% in the IVIG group (34 of 92 patients) and 58.0% in the acetaminophen group (54 of 93 patients) (OR = 8.26, p = 0.004). In a propensity score-matched cohort, 80 matched patients were selected. The incidence of hypotension was 37.5% in the IVIG group (15 of 40 patients) and 67.5% in the acetaminophen group (27 of 40 patients) (OR = 7.21, p = 0.007).

Conclusions

Acetaminophen induced substantially greater hypotension than IVIG in patients with sepsis, with both containing mannitol. Further studies are needed to clarify the effects on hemodynamics of mannitol contained in acetaminophen formulations.

Risk Factors for Intravenous Propacetamol-Induced Blood Pressure Drop in the Neurointensive Care Unit: A Retrospective Observational Study

BACKGROUND

Intravenous propacetamol is commonly used to control fever and pain in neurocritically ill patients in whom oral administration is often difficult. However, several studies reported that intravenous propacetamol may cause blood pressure drop. Thus, we aimed to investigate the occurrence and risk factors for intravenous propacetamol-induced blood pressure drop in neurocritically ill patients.

METHODS

This retrospective study included consecutive patients who were administered intravenous propacetamol in a neurointensive care unit at a single tertiary academic hospital between April 2013 and June 2020. The exact timing of intravenous propacetamol administration was collected from a database of the electronic barcode medication administration system. Blood pressure drop was defined as a systolic blood pressure below 90 mm Hg or a decrease by 30 mm Hg or more. Blood pressure, pulse rate, and body temperature were collected at baseline and within 2 h after intravenous propacetamol administration. The incidence of blood pressure drop was evaluated, and multivariable logistic regression analysis was performed to identify risk factors for blood pressure drop events.

RESULTS

A total of 16,586 instances of intravenous propacetamol administration in 4916 patients were eligible for this study. Intravenous propacetamol resulted in a significant decrease in systolic blood pressure (baseline 131.1 ± 17.8 mm Hg; within 1 h 124.6 ± 17.3 mm Hg; between 1 and 2 h 123.4 ± 17.4 mm Hg; P < 0.01). The incidence of blood pressure drop events was 13.5% within 2 h after intravenous propacetamol. Older age, lower or higher baseline systolic blood pressure, fever, higher Acute Physiology and Chronic Health Evaluation II score, and concomitant administration of vasopressors/inotropes or analgesics/sedatives were significant factors associated with the occurrence of blood pressure drop events after intravenous propacetamol administration.

CONCLUSIONS

Intravenous propacetamol can induce hemodynamic changes and blood pressure drop events in neurocritically ill patients. This study identified the risk factors for blood pressure drop events. On the basis of our results, judicious use of intravenous propacetamol is warranted for neurocritically ill patients with risk factors that make them more susceptible to hemodynamic changes.

A narrative review of paracetamol-induced hypotension: Keeping the patient safe

Aim

To understand the prevalence and epidemiology of paracetamol‐induced hypotension and clinical implications for contemporaneous practice.

Design

Narrative review.

Methods

In May and June 2020, an open‐date literature search of English publications indexed in ProQuest, PubMed, and EBSCO was conducted with the search terms ‘acetaminophen’ and ‘hypotension’ and related search combinations (‘paracetamol’, ‘propacetamol’, ‘low blood pressure’, ‘fever’, ‘sepsis’, and ‘shock’) to identify peer‐reviewed publications of blood pressure changes after paracetamol administration in humans.

Results

A pattern of blood pressure reduction following the administration of paracetamol is demonstrated in the 27 studies included in this review. Haemodynamic intervention often followed persistent blood pressure reduction, and was greatest in febrile critically ill patients who received parenteral paracetamol.

Effect of Intravenous Acetaminophen on Mean Arterial Blood Pressure: A Post Hoc Analysis of the EFfect of Intravenous ACetaminophen on PosToperative HypOxemia After Abdominal SurgeRy Trial

BACKGROUND

Acetaminophen is commonly used as part of multimodal analgesia for acute pain. The intravenous formulation offers a more predictable bioavailability compared to oral and rectal acetaminophen. There have been reports of hypotension with intravenous acetaminophen attributable to centrally mediated and vasodilatory effects. We tested the hypothesis that in adults having abdominal surgery the use of intravenous acetaminophen versus placebo for postoperative pain management is associated with a decrease in mean arterial pressure (MAP) after its administration.

METHODS

This is a substudy of eFfect of intravenous ACetaminophen on posToperative hypOxemia after abdominal surgeRy (FACTOR) trial (NCT02156154). FACTOR trial randomly assigned adults undergoing abdominal surgery to either 1 g of acetaminophen or placebo every 6 hours during the first postoperative 48 hours. Continuous monitoring of blood pressure was obtained by noninvasive ViSi Mobile device (Sotera Wireless, Inc, San Diego, CA) at 15-second intervals during initial 48 hours postoperatively. We excluded patients without continuous monitoring data available. The primary outcome was the MAP difference between MAP 5 minutes before study drug administration (baseline) and MAP 30 minutes poststudy drug administration initiation. We used a linear mixed effects model to assess the treatment effect on MAP change. The secondary outcome was MAP area under baseline (AUB) during the 30 minutes after treatment. In a sensitivity analysis of change in MAP from predrug to postdrug administration, we instead used postdrug MAP as the outcome adjusting for the baseline MAP in the model.

RESULTS

Among 358 patients analyzed, 182 received acetaminophen and 176 placebo. The mean (standard deviation [SD]) of average MAP change was -0.75 (5.9) mm Hg for the treatment and 0.32 (6.3) mm Hg for the placebo. Acetaminophen was found to decrease the MAP from baseline more than placebo after drug administration. The estimated difference in mean change of MAP was -1.03 (95% confidence interval [CI] -1.60 to -0.47) mm Hg; P < .001. The sensitivity analysis showed postoperative MAP in the acetaminophen group was 1.33 (95% CI, 0.76-1.90) mm Hg lower than in the placebo group (P < .001). The median of MAP AUB was 33 [Q1 = 3.3, Q3 = 109] mm Hg × minutes for the treatment and 23 [1.6, 79] mm Hg × minutes for the placebo. Acetaminophen was found to increase the AUB with an estimated median difference of 15 (95% CI, 5-25) mm Hg × minutes (P = .003).

CONCLUSIONS

Intravenous acetaminophen decreases MAP after its administration. However, this decrease does not appear to be clinically meaningful. Clinicians should not refrain to use intravenous acetaminophen for acute pain management because of worries of hypotension.

Hemodynamic effects of intravenous paracetamol in critically ill children with septic shock on inotropic support

Background

Treatment with intravenous paracetamol may impair hemodynamics in critically ill adults. Few data are available in children. The aim of this study was to investigate the frequency, extent, and risk factors of hypotension following intravenous paracetamol administration in children with septic shock on inotropic support.

Methods

We retrospectively reviewed the electronic medical charts of all children aged 1 month to 18 years with septic shock who were treated with intravenous paracetamol while on inotropic support at the critical care unit of a tertiary pediatric medical center in 2013–2018. Data were collected on patient demographics, underlying disease, Pediatric Logistic Organ Dysfunction (PELOD) score, hemodynamic parameters before and up to 120 min after paracetamol administration, and need for inotropic support or intravenous fluid bolus. The main outcome measures were a change in blood pressure, hypotension, and hypotension requiring intervention.

Results

The cohort included 45 children of mean age 8.9 ± 5.1 years. The mean inotropic support score was 12.1 ± 9.5. A total of 105 doses of paracetamol were administered. The lowest mean systolic pressure (108 ± 15 mmHg) was recorded at 60 min (p = 0.002). Systolic blood pressure decreased at 30, 60, 90, and 120 min after delivery of 50, 67, 61, and 59 drug doses, respectively. There were 5 events of systolic hypotension (decrease of 1 to 16 mmHg below systolic blood pressure hypotensive value). Mean arterial pressure decreased by ≥ 15% in 8 drug doses at 30 min (7.6%, mean − 19 ± 4 mmHg), 18 doses at 60 min (17.1%, mean − 20 ± 7 mmHg), 16 doses at 90 min (15.2%, mean − 20 ± 5 mmHg), and 17 doses at 120 min (16.2%, mean − 19 ± 5 mmHg). Mean arterial hypotension occurred at the respective time points in 2, 13, 10, and 9 drug doses. After 12 drug doses (11.4%), patients required an inotropic dose increment or fluid bolus.

Conclusions

Hypotensive events are not uncommon in critically ill children on inotropic support treated with intravenous paracetamol, and physicians should be alert to their occurrence and the need for intervention.

Hypotensive Response to IV Acetaminophen in Pediatric Cardiac Patients

OBJECTIVES

Acetaminophen is ubiquitously used as antipyretic/analgesic administered IV to patients undergoing surgery and to critically ill patients when enteral routes are not possible. Widely believed to be safe and free of adverse side effects, concerns have developed in adult literature regarding the association of IV acetaminophen and transient hypotension. We hypothesize that there are hemodynamic effects after IV acetaminophen in the PICU and assess the prevalence of such in a large pediatric cardiovascular ICU population using high-fidelity data.

DESIGN

Observational study analyzing an enormous set of continuous physiologic data including millions of beat to beat blood pressures surrounding medication administration.

SETTING

Quaternary pediatric cardiovascular ICU between January 1, 2013, and November 13, 2017.

PATIENTS

All patients less than or equal to 18 years old who received IV acetaminophen. Mechanical support devices excluded.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Physiologic vital sign data were analyzed in 5-minute intervals starting 60 minutes before through 180 minutes after completion. Hypotension defined as mean arterial pressure -15% from baseline and relative hypotension defined -10%. Only doses where patients received no other medications, including vasopressors, within the previous hour were included. t test and a correlation matrix were used to eliminate correlated factors before a logistic regression analysis was performed. Six-hundred eight patients received 777 IV acetaminophen doses. Median age was 8.8 months (interquartile range, 2-62 mo) with a dose of 12.5 mg/kg (interquartile range, 10-15 mg/kg). Data were normalized for age and reference values. One in 20 doses (5%) were associated with hypotension, and one in five (20%) associated with relative hypotension. Univariate analysis revealed hypotension associated with age, baseline mean arterial pressure, and skin temperature (p = 0.05, 0.01, and 0.09). Logistic regression revealed mean arterial pressure (p = 0.01) and age (p = 0.05) remained predictive for hypotension.

CONCLUSIONS

In isolation of other medication, a hemodynamic response to IV acetaminophen has a higher prevalence in critically ill children with cardiac disease than previously thought and justifies controlled studies in the perioperative and critical care setting. The added impact on individual patient hemodynamics and physiologic instability will require further study.

The Hemodynamic Effect of Intravenous Paracetamol in Children: A Retrospective Chart Review

AIM

Studies in adults have reported frequent episodes of blood pressure drops following intravenous paracetamol administration. We aimed to investigate the hemodynamic effects of intravenous paracetamol in critically ill children.

METHODS

The charts of 100 pediatric intensive care patients (age range 0.1-18 years) who were treated with intravenous paracetamol between March and September 2017 were retrospectively reviewed. A hemodynamic event was defined as a drop of > 15% in systolic or mean arterial blood pressure within 120 min after drug administration. Hypotension was defined as either a drop in systolic blood pressure (SBP) below the 5th percentile for age or a hemodynamic event associated with tachycardia, increased lactate level, or treatment with a fluid bolus or vasopressors.

RESULTS

A hemodynamic event was observed in 39 patients (39%). In these patients, SBP was in the pre-hypertension or hypertension values in 36/39 patients before paracetamol administration, median (IQR) SBP decreased from the 99th (95-99) percentile for age before to the 50th (50-95) percentile after paracetamol (p < 0.001) and mean heart rate was 137 bpm before treatment and 115 bpm after (p = 0.002). SBP values did not drop below the 5th percentile in any patient. In 15 patients diagnosed with shock on admission, paracetamol treatment did not cause an increase in vasopressor treatment after drug administration.

CONCLUSIONS

In the present study of critically ill pediatric patients, intravenous paracetamol administration was associated with a drop in SBP from high to normal values for age, possibly due to pain relief, with no evidence for a negative hemodynamic event.

Intravenous Acetaminophen-Induced Hypotension: A Review of the Current Literature

Objective: Recent literature suggests that intravenous (IV) administration may cause hypotension in hospitalized patients; data further suggest that this effect is most pronounced in the critically ill. The purpose of this review is to identify and evaluate current literature that addresses the incidence and implications of IV acetaminophen-induced hypotension. Data Sources: A literature search of MEDLINE, Cochrane, and EMBASE databases was performed (2002-2019) using the following terms: acetaminophen, paracetamol, intravenous, and hypotension. Abstracts and peer-reviewed publications were reviewed. Study Selection and Data Extraction: Relevant English-language studies conducted in humans evaluating the hemodynamic effects of IV acetaminophen were considered. Data Synthesis: A majority of the 19 studies included in this review identified a statistically significant drop in hemodynamic variables after the administration of 500 to 1000 mg IV acetaminophen as measured by changes in systolic blood pressure, diastolic blood pressure, or mean arterial pressure. Of the trials reporting vasopressor use, the authors found a significant increase in vasopressor requirements following IV acetaminophen administration. Relevance to Patient Care and Clinical Practice: This review represents the first comprehensive review of IV acetaminophen-induced hypotension. The findings raise the question of whether IV acetaminophen is an appropriate choice for inpatient pain or temperature management in the critically ill. Conclusions: Available evidence indicates that the administration of IV acetaminophen may be harmful in the critically ill. Additional monitoring is likely required when using IV acetaminophen in this specific population, particularly if a patient is hemodynamically unstable prior to administration.

The hemodynamic effects of intravenous paracetamol (acetaminophen) vs normal saline in cardiac surgery patients: A single center placebo controlled randomized study

The hemodynamic effects of intravenous (IV) paracetamol in patients undergoing cardiac surgery are unknown. We performed a prospective single center placebo controlled randomized study with parallel group design in adult patients undergoing elective cardiac surgery. Participants received paracetamol (1 gram) IV or placebo (an equal volume of 0.9% saline) preoperatively followed by two postoperative doses 6 hours apart. The primary endpoint was the absolute change in systolic (SBP) 30 minutes after the preoperative infusion, analysed using an ANCOVA model. Secondary endpoints included absolute changes in mean arterial pressure (MAP) and diastolic blood pressure (DPB), and other key hemodynamic variables after each infusion. All other endpoints were analysed using random-effect generalized least squares regression modelling with individual patients treated as random effects. Fifty participants were randomly assigned to receive paracetamol (n = 25) or placebo (n = 25). Post preoperative infusion, paracetamol decreased SBP by a mean (SD) of 13 (18) mmHg, p = 0.02, compared to a mean (SD) of 1 (11) mmHg with saline. Paracetamol decreased MAP and DBP by a mean (SD) of 9 (12) mmHg and 8 (9) mmHg (p = 0.01 and 0.02), respectively, compared to a mean (SD) of 1 (8) mmHg and 0 (6) mmHg with placebo. Postoperatively, there were no significant differences in pressure or flow based hemodynamic parameters in both groups. This study provides high quality evidence that the administration of IV paracetamol in patients undergoing cardiac surgery causes a transient decrease in preoperative blood pressure when administered before surgery but no adverse hemodynamic effects when administered in the postoperative setting.