Hot Saline Irrigation Study
Condition: Sinusitis
MeSH terms: Sinusitis
Study type: Interventional

Summary: 
      Many methods have been used to reduce bleeding during sinus surgery (FESS) in order to allow
      for the best surgical view and to reduce risk while in surgery.

      Warm irrigation fluid is believed to accelerate the clotting mechanism in the human body. The
      investigators would like to determine if hot saline irrigation (HSI) compared to room
      temperature saline irrigation (RTSI) can control bleeding during FESS.

      The hypothesis is that HSI is more effective than RTSI in reducing intraoperative bleeding
      during FESS.
    

Detailed description: 
      Background and Significance:

      Functional endoscopic sinus surgery (FESS) is a minimally invasive surgery to relieve
      obstruction and to facilitate drainage and ventilation of the paranasal sinuses. It is a
      common rhinologic procedure that is safe, comfortable and allows quick patient recovery. As
      the paranasal sinuses have complex anatomy and are surrounded by important structures, there
      are risks of serious orbital and intracranial injuries. These risks are increased if
      visualization during surgery is impaired with bleeding. The endoscopically magnified
      operative field in sinus surgery makes even a small amount of bleeding a potentially
      significant hindrance. Hence, numerous methods to reduce intraoperative bleeding during FESS
      have been described. These include the use of preoperative nasal decongestion (such as
      topical oxymetazoline, cocaine and adrenaline), preoperative oral tranexamic acid,
      intraoperative injection of the lateral nasal wall with lidocaine and adrenaline and
      intraoperative controlled hypotension (using total intravenous anaesthesia and B-blockers) as
      well as the head up position during surgery. The success rates of these methods have been
      variable and some of these techniques are associated with adverse cardiopulmonary events.1-7
      Visual compromise secondary to bleeding remains a problem during FESS and the ideal method to
      reduce intraoperative bleeding remains elusive.

      Hot water irrigation (HWI) was first used by obstetricians in controlling postpartum bleeding
      over a hundred years ago.8 Its use in the control of intractable epistaxis was first
      described by Guice in 1878.9 In a histological study of nasal mucosa of rabbits irrigated
      with hot water, Stangerup and Thomsen found that temperatures of up to 50 degrees Celsius
      produces vasodilation and edema of the nasal mucosa without necrosis. They postulated that
      mucosal edema leads to compression of the bleeding vessels and may trigger and accelerate the
      clotting cascade.10 Stangerup et al found that in their series of 122 patients, posterior
      epistaxis was controlled in 55% of patients treated with HWI compared to 44% in the group
      treated with nasal packing.11 Novoa and Schlegel-Wagner subsequently showed that 82% of
      patients with intractable posterior epistaxis can be arrested with HWI.12 HWI has also led to
      reduced hospital stay, reduced number of surgical procedures, less pain and less nasal
      trauma. As continuous exposure of the nasal mucosa to pure water for 30 minutes has been
      shown by an in-vitro study to cause severe damage to the epithelial cells, we have decided to
      use hot normal saline in our study.13 Although hot saline irrigation (HSI) has been used in
      FESS and endoscopic skull base surgery, there are currently no reports in the English
      literature on its effectiveness.

      Aim:

      To assess the effectiveness of hot saline irrigation (HSI) compared to room temperature
      saline irrigation (RTSI) in the control of intraoperative bleeding during FESS.

      Hypothesis:

      HSI is more effective than RTSI in reducing intraoperative bleeding during FESS

      Experimental design and methods:

      Target population:

      Patients are recruited from the St. Paul's Sinus Centre at St. Paul's hospital in Vancouver,
      Canada.

      Sample size: 60 patients (30 patients in each arm)

      Preoperative data collection:

      The following data is collected preoperatively:

        1. Patient's demographics (age, sex, race)

        2. Preoperative Lund and Mackay Score

        3. Presence of polyps

      Research design:

      Double blind randomized control trial

      Preoperative:

      All patients are treated with a one-week course of prednisone 20mg once a day and oral
      antibiotics (clavulin or clindamycin if penicillin) prior to surgical intervention.

      Intraoperative:

      Procedure:

      Using a closed envelope system, patients enrolled in the study are randomized to receive
      either HSI (defined as temperatures of 45-50 degrees Celsius) or RTSI (defined as temperature
      of the operating room). Both the patient and the surgeon are blinded to the temperature of
      the irrigation fluid used during surgery. After randomization, a nominated research assistant
      will receive instructions to prepare the hot or room temperature saline solution.

      Experimental arm:

      Hot saline is prepared by first placing 2 litres of sterile normal saline (0.9%) into a basin
      (IntraTemp Therma BasinTM) that is wrapped in a sterile disposable drape (IntraTemp Therma
      Basin DrapeTM). The basin is then placed in a medical grade warmer (IntraTemp Fluid Warming
      SystemTM). The warmer is set to heat the saline up to a temperature of 50 degrees Celsius. An
      external digital thermometer is placed in the saline at all times to ensure that the
      temperature is between 45-50 degrees.

      Control arm:

      Room temperature saline is prepared in the same manner except that the warmer is switched off
      and the temperature of the saline in the basin is left to equilibrate to the temperature of
      the operating room.

      In both arms, a 60 cc syringe attached to an olive tip long curve suction is used to draw the
      irrigation fluid from the basin. The surgical field is flushed with 20 cc of hot or room
      temperature saline at five minutes intervals by a research assistant. Additional flushes with
      hot or room temperature saline can be administered in between the five-minute intervals upon
      request by the surgeon. The degree of bleeding in the surgical field is scored by the
      operating surgeon using the validated Boezaart and van der Merwe Grading System14. This 0 to
      5-point scale will be used to outline the amount of suction required to rid the area of blood
      disrupting vision. A score of 0 is given for an area with no bleeding, 1 for slight bleeding
      with no suction required, 2 for slight bleeding requiring suction, 3 for moderate bleeding
      which improves for several seconds once suction has occurred, 4 for moderate bleeding which
      restarts directly after suctioning and 5 for severe bleeding which occurs faster then can be
      removed14. Surgical field of view will be assessed and scored every 15 minutes for the
      duration of the surgery. At the end of the procedure, the estimated blood loss is calculated
      by subtracting the total amount of irrigation fluid used from the fluid in the suction
      bottle. The total amount of HSI or RTSI administered and time of surgery are documented.

      Surgery:

      Patients are placed under general anesthesia and intubated with endotracheal tubes.
      Immediately after general anesthesia, both nasal cavities are packed with neuropatties soaked
      with Otrivin (xylometazolin 0.05%). The patients' heads are elevated 15 degrees up. The image
      guided system is set up and each nasal cavity is examined with a 0 degree endoscope. A 10 cm
      merocel is cut into a third of its normal size and inserted to the back of the nasopharynx,
      to prevent blood from flowing into the oropharynx and larynx. An artery forceps is clipped
      onto the merocel string to prevent dislodgement of the merocel into the larynx or oropharynx.
      FESS is performed using the technique described by Messerklinger15 and with a microdebrider
      when deemed necessary. The extent of the operation depends on the severity of the disease
      seen on the pre-operative CT scan of the paranasal sinus.

      Data collection and analysis:

      This is a pilot study; hence the statistical analysis will be completed at the end of the
      study.

      Clinically significant change in intra-operative bleeding will be defined as a change in
      Boezaart scoring by 20%, or one point in relation to the scale. All data collected for this
      study will be gathered in a password protected Microsoft Excel spreadsheet file. Each patient
      will be assigned unique identification allowing for no patient data to be recorded. The
      Microsoft Excel database will include:

        -  Age

        -  Sex

        -  Pre-existing health conditions

        -  Current medications

        -  Lund-Kennedy CT score

        -  CRS with or without polyposis

        -  Primary or revision surgery

        -  Anesthesia infusion

        -  MAP (15 minute intervals)

        -  Pulse rate (15 minute intervals)

        -  Endoscopic surgical field scores (15 minute intervals)

        -  Intra-operative complications

        -  Microdebrider usage

        -  Total blood loss

        -  Total time of surgery

        -  Total saline irrigation used

      Risk:

      The use of nasal irrigation of up to 50 degrees Celsius have been shown to be safe on the
      epithelium of rabbit nasal mucosa studied in-vitro.10 In addition, studies have shown that
      irrigation of the human nasal mucosa with temperatures of up to 50 degrees Celsius did not
      result in any complications.11,12 Hot saline irrigation has been widely used for skull base
      and endoscopic sinus surgery for many years with no known reported complication in the
      English literature.

      Difficulties and limitation:

      Patient recruitment:

      Based on the surgical volume at St Paul's Sinus Centre, we do not foresee any difficulties in
      achieving the target sample size. The St Paul's Sinus Centre is actively involved in
      research. Many of our patients are aware of this and are keen to participate in and
      contribute to medical research.

      Achieving the desired temperature:

      The exact temperature of 50 degrees Celsius is difficult to achieve. Hence we defined our HSI
      with a range of temperature of 45-50 degrees Celsius
    

Intervention name(s): Hot saline irrigation
Intervention type(s): Procedure
Intervention description(s): The surgical field is flushed with 20 cc of hot saline (45-50 degrees Celsius) at five minutes intervals. This is in contrast to the standard of care, room temperature (20-25 degrees Celsius) saline irrigation.
Other intervention name(s): HSI
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Supportive Care
Keywords: Functional Endoscopic Sinus Surgery; Hot water irrigation