Percutaneous Nephrolithotomy with Different Temperature Irrigation and Effects on Surgical Complications and Anesthesiology Applications

Introduction

Percutaneous nephrolithotomy (PCNL) is a commonly used method in the operation of kidney stones >2 cm. ¹ Advantages compared to open surgery are renal functional loss, low cost, less postoperative pain, short hospital stays, and small scarring. ² PCNL can be applied under spinal, epidural, or general anesthesia. ³ It can also be applied in the prone position, in the most supine position. ⁴ Endoscopic procedures, such as PCNL, require continuous irrigation of fluids to better observe and remove stones and blood clots. The normal saline for PCNL, especially in patients with renal insufficiency, is safe and should be recommended for this purpose. ⁵ There is a significant relationship between the amount of irrigation fluid used during the total operation time and the temperature drop. ⁶ Hypothermia is a common perioperative complication and there are a number of complications and side effects associated with hypothermia, such as cardiac arrhythmias and ischemia, decreased drug metabolism, late development and anesthesia late recovery, increased infection rate, bleeding disorders, high oxygen consumption, peripheral circulation disturbance, hypercarbia, hypoxia, and lactic acidosis. ^{6 –8} This study investigated the effects of irrigation solutions applied PCNL at 22°C or 37°C on late-onset complications such as hypothermia and postoperative anesthesia, shivering, wake-up time, and excessive bleeding.

Materials and Methods

This is a retrospective view of prospective recorded data study. The local institute ethics comitee approved the study. All patients read and understood the study. Then they signed the consent forms. Between June 2016 and April 2018, all consecutive PCNL operations were evaluated. Patient's data were recorded on Microsoft Excel spread sheet. All patients with approximately the same stone size and an indication for PCNL operation were randomly selected and included in the study. The anesthesiologist team did not know which irrigation group was in operation (blinded). Exclusion criteria were patients with missing information, <18 year-old patients, and not want to join the study. Only patients with American Society of Anesthesiologists (ASA) 1 and ASA 2 score were included in the study. All patients were under general anesthesia using the same type of medication. General anesthesia was induced with intravenous propofol (2 mg/kg) plus fentanyl (2 μg/kg), and neuromuscular blockade was achieved with rocuronium (0.6 mg/kg). After tracheal intubation, anesthesia was maintained with 1 minimum alveolar concentration of sevoflurane (2%–2.5%) in a 50% oxygen and air. Nitrous oxide was not used. Remifentanil infusions (0.1–0.2 μg/kg per minute) were used for analgesia.

During the study, the same urologic surgery team worked in the same operation room and no additional heating device was applied to the patient during the operation. The height of the irrigation fluid was at the same level (∼60 cm high from the patient) and tried the same pressure as in each operation. Body temperature measurements were made by oral route. There were 108 PCNL patients. Fifty-four of the 108 patients who received PNCL indications were administered serum irrigation at room temperature (22°C) during operation (room temperature group, RTG) and 54 patients were given irrigation suitable for body temperature (37°C) (body temperature group, BTG). In the surgical procedure, 5F or 6F ureter catheters were placed under C-arm fluoroscopy. The patients were placed to the prone position and the kidney collecting system was accessed by needle puncture in the fluoroscopic guidance. After Amplatz dilatation, 30F renal sheath was used. Stone fragmentation was carried out with pneumatic lithotripter and excreted using the previously described aspiration technique. ⁹ At the end of the procedures, a 16F foley catheter was placed for nephrostomy. The body temperature of the patients during and after the operation, the amount of irrigation fluid used, the size and location of the kidney stones, the duration of the operation, postoperative shivering time during the patient's wake-up period, pre- and postoperative hemoglobin value, additional blood requirements, postoperative analgesic requirements, and postoperative urinary tract infections were recorded. The general characteristics of patients with PCNL are given in Table 1. The wake-up time for the patients was calculated as the time between complete discontinuation of anesthesia delivery to correct response to verbal commands in supine position end of the operation.

Results

Patients' age, gender distribution, height, weight, and body mass index (BMI) (p < 0.05) showed no significant difference in BTG and RTG. There was no significant difference in the size of the stones, the preoperative fever, and postoperative analgesic requirement, the duration of operation, the irrigation amount, and postoperative urinary tract infections in the RTG and BTG (p > 0.05). Postoperative fever was significantly higher in the BTG than in the RTG (p < 0.05). Postoperative hemoglobin (Hb) reduction was significantly higher (p < 0.05) in the BTG than the RTG. The amount of hemorrhage in the patients who were irrigated the RTG was significantly less also (p < 0.05). The duration of waking in the RTG was significantly higher (p < 0.05) than the BTG (Table 2).

Discussion

PCNL plays an important role in managing especially large (>2 cm) renal stones and/or staghorn renal stones. ¹⁰ During PCNL, saline is usually used as irrigating fluid. The irrigation used is as important as the type of fluid, and pressure and temperature are important in terms of surgical complications.

The general characteristics of the patients, stone size and surgical team, and environment and technique were distributed equally as much as possible and we tried to minimize the effect of these on the results for both groups. Nevertheless, there are limtations that may affect our results. It is necessary to indicate the differences due to the personal comorbidities of the patients, especially except for the surgical procedure. In addition, room temperature may be affected by many factors and may vary slightly.

There are a lot of studies about the type of irrigation fluids used and the pressure. ^5,11 However, the number of studies showing how the temperature of the fluid used affects surgical and anesthetic complications is rather low. ¹² Kukreja et al. assessed fluid absorption resulting from the use of irrigation fluid in large quantities during PCNL. ¹³ They warned, clinically important in patients with impaired heart failure or renal impairment, which may lead to fluid loading in pediatric patients. Guzelburc and coworkers compared irrigation volume between Retrograde Intrarenal Surgery (RIRS) and PCNL. They found that minimum and maximum ranges of fluid absorption were 20–573 mL for RIRS and 13–364 mL for PCNL. The increase in fluid absorbed volume was observed as a result of the given amount of irrigating fluid used in the PCNL group. However, increase in BMI, stone size, and hydronephrosis did not affect fluid absorption significantly in either of the two operation techniques in correlation analyzes. ¹⁴ Absorption of irrigation fluid leads to cardiac and hemodynamic disorders in patients and is associated with the risk of infection. Previously, irrigation fluid temperature and postoperative analgesic requirement and infection development have not been investigated in the literature. In our study, there was no significant difference in analgesic requirement and infection development after PCNL using irrigation fluid at both temperatures.

One of the most important complications of PCNL is bleeding during and/or after operation. Although bleeding is associated with many factors during operation, the most important of these is the multiple-tract access and long duration time of the operation such as for staghorn stones. ¹⁵ When the relationship between irrigation fluid temperature and PCNL bleeding was examined, it was found that Tekgul and colleagues did not make a significant difference between the hemoglobin declines in the studies of 60 patients in the room temperature of 21° and 37° of body temperature. ¹² However, in our study with 108 patients, bleeding in the group using irrigation fluid at room temperature was significantly less. The personal comorbidities of the patients may have an effect, also in some studies, may be due to the sympathetic vasodilator effect of heat increase. ^16,17 This increase in the amount of bleeding may be due to the difficulty of the protective vasoconstriction mechanism that may occur during bleeding or because the dilated vessels can be more fragile.

Hypothermia is another important problem in PCNL, which is made with irrigation fluid used in the room temperature. This leads to a number of complications such as anesthesia late emergence, anesthesia late recovery, and shivering. ^12,18 Tekgul et al. found that the difference between the initial and the final peripheral body temperature was 0.8°C ± 0.7°C in group body tempaterature and 1.2°C ± 0.8°C in room temperature irrigation. ¹² In our study, the differences in temperature changes in patients after two different temperature irrigation were significantly higher. After the irrigation given in RTG, the temperature change was 1°C ± 0.2°C, whereas postoperative body temperature was found to be 1°C ± 0.5°C after irrigation given in BTG. Patients were monitored for shivering in the postoperative period, and related data were recorded. We have shown that heating the irrigation fluid reduced the rate of shivering in patients significantly such as Tekgul and colleagues study. ¹² A total of 15 patients (27.2%) shivering was observed in patients who used irrigation in BTG. It was noted that 32 (58.1%) of the patients shiver after irrigation used at room temperature. This was statistically significant (p < 0.05). Although many drugs, comorbidity, and etiology are known to be unclear for shivering, it may be an important parameter for the patient's awakening comfort.

After the PCNL, postnephrostomy tube placement and after taking the patient's supine position, the time from the interrupted anesthetic application to the time of the verbal response was compared. The patient's wake-up time was significantly shorter when BTG was applied (p < 0.05).

Conclusion

Our study showed that patients with PCNL with irrigation in body tempature seem to be more advantageous in terms of anesthesia department in terms of shorter duration of waking and less observation of shaking. We may also mention that it is more advantageous for the urologist to apply irrigation in the room tempature because there are few pre- and postoperative bleeding. New and multicentre studies are needed to ensure that these mechanisms are fully understood and fully implemented in our daily practice.