Orthostatic Intolerance and Hypotension After Administration of Morphine in Patients Prior to Hip or Knee Arthroplasty

Study Overview
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Brief Summary
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Incidence of orthostatic intolerance and orthostatic hypotension after intravenous administration of morphine in patients prior to hip or knee arthroplasty.

Detailed Description
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Early postoperative mobilization is crucial for recovery of patients undergoing surgery in the multimodal fast-track approach to perioperative care, since physical immobilization is highly associated with increased risk of postoperative complications and prolonged hospital length of stay. Postoperative mobilization is often delayed due to patients experiencing orthostatic hypotension (OH), defined as a drop in systolic blood pressure > 20 mmHg or diastolic blood pressure > 10 mmHg, or orthostatic intolerance (OI), characterized by dizziness, blurred vision, nausea, vomiting, sensation of heat or syncope. Previous studies have found a high incidence of postoperative OI (> 40 %) among patients undergoing total hip arthroplasty. A possible causative factor to the high occurrence of OH and OI after surgery could be postoperative pain management by administration of morphine. Morphine is known to have many side-effects including nausea, vomiting, dizziness and orthostatic hypotension. The object of this study is to isolate and estimate the effect of intravenous morphine on the incidence of OH and OI.

Official Title
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Incidence of Orthostatic Intolerance and Orthostatic Hypotension After Administration of Intravenous Morphine in Patients Prior to Hip or Knee Arthroplasty

Conditions
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Orthostatic Hypotension, Orthostatic Intolerance

Intervention / Treatment
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* Drug: Morphine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing primary unilateral total hip arthroplasty (THA), total knee arthroplasty (TKA) or unicompartmental knee arthroplasty (UKA) Patients > 18 Patients that understand and speak Danish Patients that have provided written informed consent Exclusion Criteria: Alcohol or substance abuse Habitual use of opioids Habitual use of anxiolytic, antidepressant and/or antipsychotic drugs History of previous orthostatic intolerance or hypotension Cognitive dysfunction Glomerular filtration rate (GFR) < 30 ml/min Cardiac arrhythmia

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients undergoing primary hip or knee arthroplasty<br>Patients undergoing primary hip or knee arthroplasty | Drug: Morphine<br>* Administration of 0.1 mg/kg (IBW) intravenous morphine<br>* Other names: opioid;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of orthostatic hypotension | Orthostatic hypotension is defined as a fall in systolic pressure > 20 mmHg and/or diastolic pressure > 10 mmHg during mobilization | 30 minutes after morphine administration | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in systolic arterial pressure (SAP) during mobilization | Measured in mmHg by non-invasive Lithium Dilution Cardiac Output (LiDCO) measurement | Before and 30 minutes after morphine administration | 
| Changes in diastolic arterial pressure (DAP) during mobilization | Measured in mmHg by non-invasive LiDCO | Before and 30 minutes after morphine administration | 
| Changes in mean arterial pressure (MAP) during mobilization | Measured in mmHg by non-invasive LiDCO | Before and 30 minutes after morphine administration | 
| Changes in heart rate (HR) during mobilization | Measured in beats min-1 by non-invasive LiDCO | Before and 30 minutes after morphine administration | 
| Changes in stroke volume (SV) during mobilization | Measured in mL by non-invasive LiDCO | Before and 30 minutes after morphine administration | 
| Changes in cardiac output (CO) during mobilization | Measured in L/min by non-invasive LiDCO | Before and 30 minutes after morphine administration | 
| Changes in systemic vascular resistance (SVR) during mobilization | Measured in dynes s cm-5 by non-invasive LiDCO | Before and 30 minutes after morphine administration | 
| Changes in peripheral perfusion index (PPI) during mobilization | Measured in % by Root Masimo | Before and 30 minutes after morphine administration | 
| Changes in cerebral perfusion (ScO2) during mobilization | Measured in % by Root Masimo | Before and 30 minutes after morphine administration | 
| Changes in muscular perfusion (SmO2) during mobilization | Measured in % by Root Masimo | Before and 30 minutes after morphine administration | 
| Changes in baroreflex sensitivity - vagal (BRSv) during Valsalva manoeuvre | Measured in ms | Before and 30 minutes after morphine administration | 
| Changes in heart rate variability (HRV) during Valsalva manoeuvre | Measured in ms | Before and 30 minutes after morphine administration | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Orthostatic Hypotension, Orthostatic Intolerance, Morphine, Autonomic Dysfunction