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Effect of Crystalloids With Different SID on pH, and Urinary Electrolytes During General Anesthesia

Not Applicable
Completed
Conditions
SID
Acid-Base Imbalance
Interventions
Other: 0.9% saline administration
Other: Ringer's lactate administration
Other: Plasmalyte-like solution administration
Registration Number
NCT03507062
Lead Sponsor
Fondazione Policlinico Universitario Agostino Gemelli IRCCS
Brief Summary

The present study will investigate variations in acid base equilibrium caused by the administration of four different crystalloids with increasing strong ion difference (0.9% saline, Ringer's lactate, Ringer's acetate, plasmalyte-like solution) in patients during general anesthesia.

The same crystalloid will be administered throughout the surgery. In order to assess the effect of hemodilution, every patient will receive two fluid boli with different volumes of the same solution. pH and strong ion variations, togher with the renal response to acid base disturbances, will be analysed.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
45
Inclusion Criteria
  • Adult patients (between 18 and 75 years old);
  • ASA (American Society of Anesthesiologists) physical status classification system 1 or 2;
  • Patients undergoing spinal surgery under general anesthesia, intubated and mechanically ventilated;
  • Normal preoperative albumin;
  • Surgery with an estimated duration of at least 3 hours.
Exclusion Criteria
  • Patients who are pregnant;
  • Patients with obesity (BMI > 35);
  • Patients with a chronic obstructive pulmonary disease (COPD);
  • Patients with obstructive sleep apnea (OSA) treated with CPAP;
  • Patients with chronic heart failure (CHF) with a NYHA (New York Heart Association) class ≥2;
  • Patients receiving diuretics in the pre-operative period;
  • Patients with a chronic kidney disease (CKD), defined as a GFR < 60 ml/min/1.73 m2;
  • Patients with diabetes mellitus treated with insulin;
  • Patients with myopathies; Patients undergoing a surgery with likely fluid losses or with unexpected bleeding during surgery.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Chloride-rich solution0.9% saline administrationPatients will receive two boluses of 10 and 20 ml/kg of the 0.9% saline in two different moments after at least 1 hour from each other. Plasma arterial blood gas (ABG) and electrolytes, along with plasmatic creatinine, albumin and phosphate will be measured immediately before and five minutes after fluid boluses. Urinary electrolytes (Na, K, Cl) will be measured immediately before fluid bolus and after one hour from fluid administration along with ABG and plasmatic electrolytes and creatinine, phosphate and albumin.
Low-chloride solution ARinger's lactate administrationPatients will receive two boluses of 10 and 20 ml/kg of Ringer's lactate in two different moments after at least 1 hour from each other. Plasma arterial blood gas (ABG) and electrolytes, along with plasmatic creatinine, albumin and phosphate will be measured immediately before and five minutes after fluid boluses. Urinary electrolytes (Na, K, Cl) will be measured immediately before fluid bolus and after one hour from fluid administration along with ABG and plasmatic electrolytes and creatinine, phosphate and albumin.
Very low-chloride solutionPlasmalyte-like solution administrationPatients will receive two boluses of 10 and 20 ml/kg of a plasmalyte-like solution (namely soluzione elettrolitica reintegrante \[SER\]) in two different moments after at least 1 hour from each other. Plasma arterial blood gas (ABG) and electrolytes, along with plasmatic creatinine, albumin and phosphate will be measured immediately before and five minutes after fluid boluses. Urinary electrolytes (Na, K, Cl) will be measured immediately before fluid bolus and after one hour from fluid administration along with ABG and plasmatic electrolytes and creatinine, phosphate and albumin.
Primary Outcome Measures
NameTimeMethod
pH modificationSurgery

The primary outcome of this physiological study is to evaluate, in vivo, the effect of crystalloid administration with different SID on acid base equilibrium, in particular pH variations will be considered.

Secondary Outcome Measures
NameTimeMethod
SID and plasmatic weak acid (A tot) variations measured in mEq/LSurgery

We will explore the changes in apparent SID (SIDapp) and effective SID (SIDeff) and strong ion gap (SIG), as well as A tot after administration of solutions with different SID

Urinary SID modification (mEq/L) after crystalloids administration with different SID and chloride loadSurgery

renal response to acid base disturbances caused by different crystalloid infusions and different volumes.

Trial Locations

Locations (1)

Fondazione Policlinico A. Gemelli

🇮🇹

Roma, Italy

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