An observational study in Postoperative Shivering, sponsored by Bozyaka Training and Research Hospital. Not yet recruiting at 1 site in Turkey. Open to female participants aged 18 Years to 45 Years. Per ClinicalTrials.gov, last updated 2025-05-30.
Sponsored by Bozyaka Training and Research Hospital · Observational
The goal of this observational study is to learn about the effect of menstrual cycle on postoperative shivering in women of fertile age. The main question it aims to answer is:
Postoperative shivering is a protective mechanism that the body uses to raise body temperature by rhythmic muscle contractions during hypothermia. Peroperative hypothermia is the most important cause of shivering after recovery. Shivering not only causes a decrease in patient comfort and discomfort but also increases metabolic demand by increasing oxygen consumption. This is an undesirable situation.
Women's hormonal status affects body temperature control. During the luteal phase, progesterone levels increase and this results in a 0.4 °C increase in core body temperature. The threshold for vasodilation also increases during this phase. Therefore, thermoregulation also changes during the luteal phase. Core body temperature in the follicular and luteal phase does not change with exposure to cold. However, under general anesthesia, core temperature is significantly reduced in both the luteal and follicular phase. Thermoregulatory vasoconstriction is less inhibited during luteal phase anesthesia.
The primary aim of our study was to determine the relationship between different phases of the menstrual cycle and the frequency of postoperative shivering. The secondary aim was to evaluate the incidence of intraoperative hypothermia and the duration of onset of intraoperative hypothermia in different phases of the menstrual cycle.
The study is planned as a prospective cross-sectional observational study. Female patients aged 18-45 years with ASA (American Society of Anesthesiology) score I-II who will undergo elective surgery for open technique septoplasty or rhinoplasty will be included in the study. They will be recorded in two groups as follicular group (F) and luteal group (L).
Patients data will be recorded;
Bozyaka Training and Research Hospital is the lead sponsor of 51 studies on the registry; 5 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Female patients scheduled for elective nose surgery
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
ASA physical status
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Follicular phase of menstrual cycle
Luteal phase of menstrual cycle
Postoperative Shivering
Postanesthetic shivering will be evaluated in the postanesthesia care unit by Postanesthetic Shivering Scale. The scale is a 5-points scale. 0= no shivering 1= no visible muscle activity but piloerection, peripheral vasoconstriction, or both are present (other causes excluded); 2 = muscular activity in only one muscle group; 3 = moderate muscular activity in more than one muscle group but no generalized shaking; 4 = violent muscular activity that involves the whole body. 3 and 4 mean worse outcome as the patient needs medication to treat shivering.
Time frame: First 15 minutes after surgery
Number of patients who require meperidine
The need for intravenous meperidine administration when the postanesthetic shivering scale (PAS) of the patient is above 3.
Time frame: first 15 minutes after surgery
Number of patients whose core body temperature is below 36 °C
Intraoperative hypothermia is defined as a core body temperature below 36°C under anesthesia.
Time frame: perioperative
The time when intraoperative core body temperature is detected below 36 °C
The time when the core body temperature is below 36°C during general anesthesia.
Time frame: perioperative
Plan to share: Undecided
Start is estimated for Jun 2025; primary completion for Aug 2025, 2 months later.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in May 2025. You cannot join it, but the record below documents what was studied.
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Bozyaka Training and Research Hospital