Percutaneous nephrolithotomy (PCNL) is a common surgical procedure to remove renal calculi. During PCNL, absorption of irrigation fluid can occur, potentially increasing extravascular lung water (EVLW) and contributing to perioperative respiratory complications. Accurate, timely monitoring of EVLW and a protocolized response may reduce postoperative pulmonary adverse events. This randomized controlled trial evaluated whether a lung ultrasound (LUS)–guided, protocolized fluid management strategy could better detect and limit EVLW elevation compared with conventional central venous pressure (CVP)–based management during the perioperative period of PCNL.
This single-center randomized controlled study enrolled 181 elective PCNL cases. Participants were randomly assigned to one of two groups: conventional CVP-based fluid management (Group C) or a lung ultrasound–guided, protocolized fluid management strategy (Group LUS). The study assessed outcomes during the perioperative period, including the immediate postoperative interval.
Group C received fluid management guided by standard CVP measurements. Group LUS received a structured, protocolized management approach that incorporated serial LUS examinations to assess EVLW in real time, with predefined thresholds for intervention, including administration of furosemide as indicated. Timepoints for monitoring and intervention were defined as: before irrigation (T0), at the first administration of furosemide (T1), after irrigation (T2), and at the time of leaving the post-anesthesia care unit (PACU) (T3).
Primary outcomes were the incidence and severity of increased EVLW within 30 minutes postoperatively and the rate of postoperative hypoxemia in each group. Secondary outcomes included CVP values and LUS scores at T0, T1, T2, and T3; fluid volumes (crystalloid, colloid, total infusion, irrigation, and supplemental fluid at first furosemide administration); total furosemide dosage; anesthesia time; surgical duration; PACU stay duration; extubation time; total hospital stay; and perioperative complication rates as safety outcomes.
Compared with the CVP-guided group, the LUS-guided protocol group demonstrated a significantly lower incidence and severity of EVLW increase within 30 minutes after surgery. The LUS-guided approach was also associated with a markedly reduced rate of postoperative hypoxemia. All reported comparisons for these primary outcomes reached statistical significance (all p < 0.001), indicating a consistent advantage for LUS-guided, protocolized management in attenuating early postoperative EVLW accumulation and respiratory compromise.
Group LUS had lower LUS scores and lower CVP values at the intervention and post-irrigation timepoints (T1, T2, and T3) relative to Group C (p < 0.001). The study recorded multiple fluid-related measures (crystalloid, colloid, total infusion, irrigation volume, and supplemental fluid at first furosemide administration) and total furosemide dose; these metrics were included as secondary outcomes in the trial design. The abstract reports that LUS-guided monitoring enabled earlier detection of EVLW elevation and protocolized early intervention, which likely contributed to differences in these monitoring parameters, though the abstract does not provide detailed numeric values for each fluid metric.
Patients managed with the LUS-guided protocol experienced shorter extubation times and reduced PACU stay compared with those managed by CVP alone (p < 0.05). The trial recorded anesthesia time, surgical duration, PACU stay time, extubation time, and total hospital stay. Safety outcomes included perioperative complication rates; the abstract indicates that safety outcomes were assessed but does not present detailed complication rates or specific adverse event data.
The authors conclude that an LUS-guided, protocolized fluid management strategy that integrates real-time EVLW assessment with predefined intervention thresholds outperformed conventional CVP-based management during the perioperative period of PCNL. The superior sensitivity of LUS for early EVLW detection, combined with structured early interventions (for example, administering furosemide according to protocolized triggers), was associated with reduced postoperative hypoxemia incidence, shorter extubation time, and reduced PACU stay, reflecting improved short-term perioperative recovery.
These findings support consideration of LUS as a noninvasive, bedside tool for perioperative EVLW surveillance during procedures with substantial irrigation fluid exposure. Incorporating lung ultrasound into a protocolized fluid-management pathway may enable earlier intervention and improve immediate postoperative respiratory outcomes in PCNL patients.
A randomized trial of 181 patients undergoing PCNL compared standard CVP-based fluid management with a lung ultrasound–guided protocol. Using LUS to monitor lung water in real time allowed earlier detection of fluid accumulation in the lungs, prompted timely interventions, and reduced the severity of lung-water increase and the frequency of low oxygen levels after surgery. Patients managed with the LUS-guided protocol were extubated sooner and spent less time in the PACU. The abstract reports improved short-term recovery with the LUS-guided strategy; full trial data and detailed safety outcomes were not presented in the abstract.