Surgical Position and Hemodynamics in PCNL

Ataturk University

Status: Completed

Conditions: Hemodynamic Changes; Surgical Positioning; Percutaneous Nephrolithotomy (PCNL)

Treatments: Other: Position the patient

Study type: Observational

Funder types: Other

Identifiers

NCT07109232

Ataunihemo

Details and patient eligibility

About

This prospective study aims to evaluate the hemodynamic effects of different surgical positions-supine, lithotomy, and prone-in patients undergoing percutaneous nephrolithotomy (PCNL). Hemodynamic parameters are assessed using the Pressure Recording Analytical Method (PRAM) both while patients are awake and under general anesthesia. The study investigates how positioning-independently and in combination with anesthesia-influences cardiovascular function, including mean arterial pressure (MAP), heart rate (HR), cardiac index (CI), stroke volume index (SVI), pulse pressure variation (PPV), stroke volume variation (SVV), cardiac contractility parameters (dP/dtmax), arterial elastance (Ea), cardiac power index (CPI), and cardiac cycle efficiency (CCE). The findings are expected to contribute to optimizing perioperative management and enhancing patient safety during PCNL procedures.

Full description

This prospective clinical trial investigates the hemodynamic effects of different surgical positions-supine, lithotomy, and prone-in patients undergoing percutaneous nephrolithotomy (PCNL). The study evaluates hemodynamic variables both in the awake state and under general anesthesia to distinguish the individual and combined impacts of anesthesia and patient positioning on cardiovascular function.

Hemodynamic measurements are performed using the Pressure Recording Analytical Method (PRAM), a minimally invasive technique that allows continuous assessment of parameters such as mean arterial pressure (MAP), heart rate (HR), cardiac index (CI), pulse pressure variation (PPV), stroke volume variation (SVV), stroke volume index (SVI), cardiac contractility parameters (dP/dtmax), arterial elastance (Ea), cardiac power index (CPI), and cardiac cycle efficiency (CCE). Each patient is sequentially positioned in the three surgical positions while awake, and the same measurements are repeated after the induction of general anesthesia in the corresponding positions.

The primary aim is to determine how surgical positioning under general anesthesia alters key cardiovascular parameters. Secondary objectives include comparing hemodynamic changes across positions in both conscious and anesthetized states, identifying potential risks associated with specific positions, and guiding intraoperative patient management to improve safety and outcomes in PCNL procedures.

The study is conducted at a single center and includes adult patients with ASA physical status I-II scheduled for elective PCNL surgery. The findings are expected to provide valuable data for anesthesiologists and surgeons to optimize perioperative cardiovascular stability, particularly during position changes in urological surgeries.

Enrollment: 40 patients

Sex: All

Ages: 18 to 65 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

Participants must be between 18 and 65 years of age. Participants must have a body mass index (BMI) of less than 30 kg/m². Participants must be classified as American Society of Anesthesiologists (ASA) physical status I or II.

Participants must be scheduled to undergo elective percutaneous nephrolithotomy (PCNL) surgery.

Exclusion criteria

Participants with a known history of cardiac disease, including arrhythmia, valvular heart disease, prior cardiac surgery, presence of a pacemaker, or an implanted cardiac defibrillator, will be excluded.

Participants with renal failure will be excluded. Participants who received colloid fluid administration prior to surgery will be excluded.

Participants using vasoactive or inotropic drugs will be excluded.

Trial design

40 participants in 1 patient group

Hemodynamic Response to Position Changes

Description:

Hemodynamic variables-including mean arterial pressure (MAP), heart rate (HR), cardiac index (CI), stroke volume index (SVI), pulse pressure variation (PPV), stroke volume variation (SVV), dP/dtmax, arterial elastance (Ea), cardiac cycle efficiency (CCE), and cardiac power index (CPI)-were continuously monitored. Hemodynamic measurements were obtained at six predefined time points using the Pressure Recording Analytical Method (PRAM). The first three measurements were recorded during the pre-anesthetic period in the supine, lithotomy, and prone positions, respectively, prior to the induction of anesthesia. The latter three measurements were obtained during the anesthetized period: five minutes after induction while the patient was in the baseline supine position, five minutes after transitioning to the lithotomy position (prior to ureteral catheter placement), and five minutes after repositioning to the prone position, before surgical incision.

Treatment:

Other: Position the patient