Postoperative Residual Curarisation at Arrival in the Post-anesthesia Care Unit

A Non-interventional / Observational Study on Postoperative Residual Curarisation at Arrival in the Post-anesthesia Care Unit After Spontaneous Recovery or After Reversal of the Neuromuscular Block

Several studies have documented that neuromuscular block often persists in the postanesthesia care unit (PACU). Residual paralysis is associated with postoperative complications such as hypoxia, weakness, and respiratory failure. The data in the current literature on residual paralysis in the PACU were almost exclusively obtained with acetylcholinesterase inhibitors as they were the only reversal agents available prior to the introduction in clinical practice of sugammadex (Bridion®) in the European Union and in some other countries, except for the USA. Reassessment of practice in this regard is relevant, now that sugammadex (Bridion®) has become available in our country since 2009.

This study is an observational/non-interventional, non-randomized study involving adult patients undergoing different types of elective surgical procedures requiring general anesthesia with neuromuscular blocking drugs (NMBDs). Administration of NMBDs and reversal agents (as well as all drugs which will be used during anesthesia) will be performed in accordance with routine anesthetic practice.

The study population will comprise about 600 surgical patients. Immediately after the patients' arrival in the PACU, a study nurse will record the acceleromyographic responses of their adductor pollicis muscle as percent of the train-of-four (TOF%) on stimulation of the ulnar nerve. A TOF of 90% will be used as cut-off value to exclude residual paralysis. Pulse oximetry (SpO2) will be measured continuously throughout the PACU admission, and SpO2 values will be recorded at 1-min intervals for the first 30 min. PACU nurses caring for the patient will document the occurrence of any of the following events during the first 30 min of PACU admission: the number of episodes of hypoxemia (SpO2<90%), the lowest SpO2 observed by nursing staff, the requirement for either tactile or verbal stimulation to maintain SpO2 greater than 90%, and any clinical evidence of airway obstruction.

The primary objective is to evaluate the incidence of postoperative residual curarisation at PACU arrival in patients reversed with sugammadex (Bridion®), neostigmine and in case of spontaneous recovery.

The secondary objectives are to evaluate:

• Oxygen saturation (SpO2) at PACU arrival
• Possible episodes of SpO2 <90% in the PACU
• Airway maneuvers and/or stimulation required to maintain SpO2 >90% in the PACU
• Need for re-intubation.

Study Overview

• Status: Completed
• Conditions: Postoperative Hypoxemia; Postoperative Residual Curarisation; Postoperative Airway Obstruction
• Intervention / Treatment: Procedure: neuromuscular transmission monitoring; Procedure: Pulse oximetry measurement

Detailed Description

• Background & Rationale: Several studies have documented that neuromuscular block often persists in the PACU, even with the administration of acetylcholinesterase inhibitors. Postoperative residual curarisation ranges between 4 and 50% depending on the diagnostic criteria, the type of non-depolarizing neuromuscular blocking drug (NMBD), the administration of a reversal agent, and the use of neuromuscular monitoring. Residual paralysis is associated with postoperative complications such as hypoxia, weakness, and respiratory failure. However, these complications may have many other causes so that the role of neuromuscular block is often unrecognized. Thus, it is important to manage neuromuscular block and have a strategy to prevent, diagnose, and treat residual paralysis, with neuromuscular monitoring and reversal of neuromuscular block in routine anesthetic practice. The data in the current literature on residual paralysis in the PACU were almost exclusively obtained with acetylcholinesterase inhibitors as they were the only reversal agents available prior to the introduction in clinical practice of sugammadex (Bridion®) in the European Union and in some other countries, except for the USA. Reassessment of practice in this regard is relevant, now that sugammadex (Bridion®) has become available in our country since 2009.

Five years ago a similar exploratory, non-interventional, non-randomized study took place in Belgium. This previous study will help to assess the two different periods (2005-2011) in terms of management of neuromuscular block in the operating room of a large regional community hospital.

• Study Design: This is an observational/non-interventional, non-randomized study involving adult patients undergoing different types of elective surgical procedures requiring general anesthesia with NMBDs. This study will reflect real life clinical practice. The anesthetic technique in terms of drugs and type of monitoring used will be the entire responsibility of the anesthesiologist.

All study activities will be consistent with EU directive 2001/20/EC for non-interventional studies (also known as observational/non-interventional studies).

Administration of NMBDs and reversal agents (as well as all drugs which will be used during anesthesia) will be performed in accordance with routine anesthetic practice; will follow good clinical practice and labeling of drugs. No other interventional means, methods or procedures are scheduled than those for routine care of the patient. Furthermore, there will be no additional visits to the hospital or a mandatory visit schedule, deviating from normal clinical practice.

• Study Flowchart: On arrival to the PACU, 3 l/min oxygen will be applied to all subjects by a nasal cannula. Baseline oxygen saturation values are recorded 1 min after application of the oxygen. Immediately after the patients' arrival in the PACU, a study nurse will record their tympanic temperatures and the acceleromyographic responses of their adductor pollicis muscle as percent of the train-of-four (TOF%) on stimulation of the ulnar nerve (TOF-Watch®, Organon Ireland Ltd., a division of MSD, Swords, Co., Dublin, Ireland). The stimulus current will be set in the range 25-35 mA for tolerance purpose without compromising the results. Two consecutive TOF measurements (separated by 15 s) will be obtained, and the average of the 2 values will be recorded. If measurements differ by >10%, additional TOF measurements will be obtained (up to 4 TOF values), and the closest 2 ratios averaged. A TOF of 90% will be used as cut-off value to exclude residual paralysis. Pulse oximetry will be measured continuously throughout the PACU admission, and SpO2 values will be recorded at 1-min intervals for the first 30 min. PACU nurses caring for the patient will document the occurrence of any of the following events during the first 30 min of PACU admission: the number of episodes of hypoxemia (SpO2<90%), the lowest SpO2 observed by nursing staff, the requirement for either tactile or verbal stimulation to maintain SpO2 greater than 90%, and any clinical evidence of airway obstruction. Patient demographic data, type of surgical procedure, duration of anesthesia, as well as data collected relating to neuromuscular management, will be recorded and stored on a PC.

• Study Type: Observational
• Enrollment (Actual): 625

Contacts and Locations

Study Locations

• Belgium
  • Aalst, Belgium, 9300
    • OLV Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

The study population will comprise about 600 surgical patients (the first 600 inpatients and outpatients scheduled for anesthesia during the study period who meet the study criteria).

Description

Inclusion Criteria:

• 18 years of age or older;
• Informed consent signed;
• Admission for elective surgery;
• Administration of non-depolarizing NMBDs during surgery;
• Tracheal intubation

Exclusion Criteria:

• Evidence of renal, hepatic, metabolic, and/or neuromuscular disorders
• Ejection fraction <20%
• Admission for emergency surgery; or cardiothoracic surgery
• Reoperation during the same hospital admission

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
incidence of postoperative residual curarisation	incidence of postoperative residual curarisation (PORC) defined by a train-of-four (TOF) ratio < 0,9 at post-anesthesia care unit (PACU) arrival	Immediately after the patients' arrival in the post-anesthesia care unit (<5 min after arrival), two consecutive neuromuscular transmission measurements (separated by 15 s) will be obtained, and the average of the 2 values will be recorded.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Possible episodes of SpO2 <90% in the PACU		During the first 30 min of PACU admission
Airway maneuvers and/or stimulation required to maintain SpO2 >90% in the PACU	the requirement for either tactile or verbal stimulation to maintain SpO2 greater than 90%, and any clinical evidence of airway obstruction	During the first 30 min of PACU admission
Need for re-intubation		During the first 30 min of PACU admission

Collaborators and Investigators

• Sponsor: Onze Lieve Vrouw Hospital
• Collaborators: Merck Sharp & Dohme LLC
• Investigators: Principal Investigator: Guy Cammu, MD, PhD, OLV Hospital, Aalst, Belgium

Publications and helpful links

General Publications

• Cammu G, De Witte J, De Veylder J, Byttebier G, Vandeput D, Foubert L, Vandenbroucke G, Deloof T. Postoperative residual paralysis in outpatients versus inpatients. Anesth Analg. 2006 Feb;102(2):426-9. doi: 10.1213/01.ane.0000195543.61123.1f.

Study record dates

Study Major Dates

• Study Start: May 1, 2011
• Primary Completion (Actual): October 1, 2011
• Study Completion (Actual): October 1, 2011

Study Registration Dates

• First Submitted: May 25, 2011
• First Submitted That Met QC Criteria: May 26, 2011
• First Posted (Estimate): May 30, 2011

Study Record Updates

• Last Update Posted (Estimate): October 5, 2011
• Last Update Submitted That Met QC Criteria: October 4, 2011
• Last Verified: October 1, 2011

More Information

Terms related to this study

• Keywords: Muscle Relaxation
• Additional Relevant MeSH Terms: Pathologic Processes; Respiratory Tract Diseases; Respiration Disorders; Postoperative Complications; Signs and Symptoms, Respiratory; Respiratory Insufficiency; Airway Obstruction; Hypoxia; Delayed Emergence from Anesthesia
• Other Study ID Numbers: B126201110617; IISP ID 39443 (Other Grant/Funding Number: MSD (Merck Sharp & Dohme))