Evidence Level A
- Intracervical injection of 8 mL of a dilute vasopressin solution (0.05 U/mL) immediately prior to the procedure reduces distending media absorption during resectoscopic surgery. Such administration may also reduce the force required for cervical dilation. (Discussed in section: Intracervical Vasopressin)
- The uterine cavity distention pressure should be the lowest pressure necessary to distend the uterine cavity and ideally should be maintained below the mean arterial pressure (MAP) (Discussed in section: Infusion and Evacuation Techniques)
Evidence Level B
- Excessive absorption of hypotonic fluids such as glycine 1.5% or sorbitol 3% can result in fluid overload and hypotonic hyponatremia, causing permanent neurologic complications or death (Discussed in section: Mechanisms, Consequences and Incidence of Excess Fluid Extravasation: Low viscosity distention media)
- The risk of hypotonic encephalopathy is greater in reproductive-aged women than in postmenopausal women. (Discussed in section: Mechanisms, Consequences and Incidence of Excess Fluid Extravasation: Low viscosity distention media)
- When compared with electrolyte-free media, saline appears to have a safer profile. (Discussed in section: Managing Fluid Media: Selection of distending media)
- Excessive absorption of isotonic fluids such as normal saline can cause severe complications. Although isotonic fluids do not cause cerebral edema,
there is still a mandate for continuous and accurate measurement of input and output for the calculation of fluid absorption. (Discussed in section: Managing Fluid Media: Selection of distending media)
- The risk of systemic absorption varies with the procedure and increases when myometrial integrity is breached with procedures such as myomectomy. In such instances, patients should be counseled that more than one procedure may be required. (Discussed in section: Reducing the Volume of Systemic Absorption–Preoperative)
- Due to the conflicting evidence regarding their impact on the volume of fluid deficit during resectoscopic surgery, the decision to use a gonadotropin-releasing hormone (GnRH) agonist in premenopausal patients to reduce extent of fluid deficit should be made at the discretion of the provider. (Discussed in section: Reducing the Volume of Systemic Absorption–Preoperative)
Evidence Level C
- CO2 is a suitable medium for the performance of diagnostic hysteroscopy but should not be used for operative hysteroscopy because of its impact on hysteroscopic visualization and the risk of CO2 embolus. (Discussed in section: Medial types: Carbon Dioxite)
- Before performing operative hysteroscopy with liquid distending medium, it is important to purge the air out of the system and during the procedure to change the liquid-containing bag before it is completely emptied. (Discussed in section: Media types: Carbon Dioxide)
- The risks associated with distending media overload may be reduced by limiting the degree of preoperative hydration with oral or intravenous fluids. (No published evidence: committee recommendation)
- Shortly prior to performing resectoscopic surgery, it is advisable to obtain baseline levels of serum electrolytes including sodium, chloride, and potassium in women on diuretics or with medical conditions that may predispose to electrolyte disorders.
- The following statements on maximum fluid deficits are based on expert opinion. The patient should be carefully evaluated, with consideration to terminating the procedure expeditiously if intravasation is known or thought to reach the volume
in these clinical contexts. For elderly patients and others with comorbid conditions including compromised cardiovascular systems, a maximum
fluid deficit of 750 mL is recommended. (Discussed in section: Management of Excess Absorption of Distending Media)
a. For healthy patients, the maximum fluid deficit of 1000 mL is suggested when using hypotonic solutions. This is based on a decrease in serum sodium of 10 mmol, with absorbed volume of around 1000 mL. The maximum limit for isotonic solution is unclear, but 2500 mL has been advocated in the previous AAGL Guidelines. Individualization and the anesthesiologist’s opinion should be obtained.
b. When high-viscosity distending media are used, the maximum infused volume should not exceed 500 mL, and in the elderly and those with cardiopulmonary compromise should not exceed 300 mL.
- When maximum absorption occurs with electrolyte-free distending media, immediate measurement of plasma electrolytes and osmolality is recommended. (Discussed in section: Management of Excess Absorption of Distending Media)
- Normal saline should be used wherever possible for operative hysteroscopic surgery to reduce the risk of hyponatremia and hypo-osmolarity. Normal saline should be used for distention during operative hysteroscopic procedures not requiring the use of monopolar electrosurgical instruments. (Discussed in section: Managing Fluid Media: Selection of distending media)
- The surgical team should be prepared to accurately monitor distending fluid medium input and output, including all 3 potential sources: return from the hysteroscope, spill from the vagina, and loss to the floor. An automated system for continuous calculation of fluid deficit is recommended. (Discussed in section: Monitoring Absorption)
- The use of an automated fluid management system is recommended. Such systems should ideally comprise an infusion pump that allows determination and continuous monitoring of true intrauterine distention pressure and a system for accurate measurement of fluid deficit. (Discussed in section: Reducing the Volume of Systemic Absorption; and Monitoring Absorption)
- The surgical team should, prior to the start of the case, predetermine the maximum acceptable volume of systemically absorbed distending media considering both the medical condition of the patient, and the osmolality and electrolyte content of the media to be used.