Pain after Licorice or Sugar-Water Gargling in Patients Recovering from Oropharyngeal Surgery-A Randomized, Double-Blind Trial.

Background: Glycyrrhiza glabrata (licorice) is used in traditional medicine and herbal remedies and reduces sore throats consequent to intubation, but whether it is protective for more intense pain after oropharyngeal surgery remains unclear. We thus tested the joint hypothesis that gargling with licorice, which has anti-inflammatory and antioxidant properties, reduces postoperative pain and morphine consumption.

Methods: We enrolled patients having elective oropharyngeal surgery.

Opioid use after propofol or sevoflurane anesthesia: a randomized trial.

Background: The intravenous anesthetic propofol is a gamma-aminobutyric acid A receptor agonist. Propofol promotes analgesia by depressing nociceptive transmission in peripheral neurons, antagonizing N-methyl-D-aspartate receptors, and activating gamma-aminobutyric acid A receptors in dorsal root ganglion receptor cells. Nevertheless, it remains unclear whether intraoperative propofol causes clinically meaningful postoperative analgesia.

Pharyngeal Oxygen Insufflation During AirTraq Laryngoscopy Slows Arterial Desaturation in Infants and Small Children.

Background: The extent to which insufflation of oxygen into the posterior pharynx during laryngoscopy prolongs adequate saturation in infants and small children remains unknown. Therefore, we compared oxygen saturation over time in preoxygenated small children with and without posterior pharynx oxygen insufflation.

Methods: After induction of anesthesia with sevoflurane and propofol, infants and small children were preoxygenated with 100% oxygen for 3 minutes.

Intra-operative rewarming with Hot Dog(®) resistive heating and forced-air heating: a trial of lower-body warming.

Resistive heating is an alternative to forced-air warming which is currently the most commonly used intra-operative warming system. We therefore tested the hypothesis that rewarming rates are similar with Hot Dog(®) (Augustine Biomedical) resistive and Bair Hugger(®) (Arizant) forced-air heating systems. We evaluated 28 patients having major maxillary tumour surgery.

Postanaesthetic considerations and complications after ambulatory anaesthesia.

Ambulatory or day-case surgery is being employed to an ever-increasing extent. Although it has many advantages, it is not suited to the needs of every patient. For example, patients who live alone, particularly the elderly, might well not be able to care for themselves adequately after such surgery and are probably at a higher risk of developing complications, including infections.

The influence of 2 surgical bandage systems on wound tissue oxygen tension.

Hypothesis: Local wound heating improves tissue oxygen tension in postoperative patients.

Setting: University hospital.

Patients: Forty normothermic and well-hydrated patients recovering from elective open abdominal surgery.

Circadian changes in the sweating-to-vasoconstriction interthreshold range.

Thermoregulatory defenses are characterized by thresholds, the core temperatures triggering each response. Core body temperature is normally maintained within the interthreshold range, temperatures between the sweating and vasoconstriction thresholds that do not trigger autonomic defenses. This range usually spans only some 0.

Local radiant heating increases subcutaneous oxygen tension.

Background: We evaluated a novel bandage that incorporates a thermostatically controlled radiant heater. We first determined optimal bandage temperature, based on increases in subcutaneous oxygen tension, a measure correlating well with resistance to infection and wound strength. We then tested the hypothesis that prolonged radiant heating would increase collagen deposition in experimental thigh wounds.

Efficacy of intraoperative cooling methods.

Background: Patients may require perioperative cooling for a variety of reasons including treatment of a malignant hyperthermia crisis and induction of therapeutic hypothermia for neurosurgery. The authors compared heat transfer and core cooling rates with five cooling methods.

Methods: Six healthy volunteers were anesthetized with desflurane and nitrous oxide.

Postanesthetic vasoconstriction slows peripheral-to-core transfer of cutaneous heat, thereby isolating the core thermal compartment.

Unlabelled: Forced-air warming during anesthesia increases core temperature comparably with and without thermoregulatory vasoconstriction. In contrast, postoperative forced-air warming may be no more effective than passive insulation. Nonthermoregulatory anesthesia-induced vasodilation may thus influence heat transfer.

Lack of nonshivering thermogenesis in infants anesthetized with fentanyl and propofol.

Background: Sweating, vasoconstriction, and shivering have been observed during general anesthesia. Among these, vasoconstriction is especially important because-once triggered-it minimizes further hypothermia. Surprisingly, the core-temperature plateau associated with vasoconstriction appears to preserve core temperature better in infants and children than adults.

Thermoregulatory vasoconstriction does not impede core warming during cutaneous heating.

Recent studies evaluating perioperative cutaneous-to-core heat transfer indicate that: Thermoregulatory vasoconstriction prevents further core cooling in anesthetized subjects during mild cooling. Thermoregulatory vasoconstriction only slightly decreases core cooling rates in anesthetized subjects during vigorous cooling. Thermoregulatory vasoconstriction does not impair vigorous core rewarming during anesthesia.

Isoflurane produces marked and nonlinear decreases in the vasoconstriction and shivering thresholds.

In summary, we present a new model for evaluating thermoregulatory effects of drug administration, pregnancy, illness, etc. Specifically, we experimentally manipulated both skin and core temperatures, and subsequently compensated for the changes in skin temperature using the relationships between skin and core contributions to thermoregulatory control. We thus were able to report our results for warm- and cold-responses in terms of calculated core-temperature thresholds at a single designated skin temperature.

Isoflurane produces marked and nonlinear decreases in the vasoconstriction and shivering thresholds.

Background: Desflurane decreases the vasoconstriction and shivering thresholds disproportionately at high anesthetic concentrations. This result contrasts with the authors' previous report that isoflurane decreases the vasoconstriction threshold linearly. It is surprising that the basic shape of the concentration-response curve should differ with these two otherwise similar anesthetics.

Rapid core-to-peripheral tissue heat transfer during cutaneous cooling.

Perioperative thermal manipulations are usually directed at the skin surface because methods of directly warming the core are invasive or ineffective. However, inadequate heat flow between peripheral and core compartments will decrease the rate at which core temperature changes. We therefore determined whether core hypothermia is delayed after initiation of surface cooling.

Thermoregulatory vasoconstriction and perianesthetic heat transfer.

Heat transfer between the core and its environment in normothermic and slightly hypothermic situations is determined largely by the influence of vasomotion on convection. Tonic vasoconstriction, the normal barrier to heat loss from the core, is impaired upon induction of anesthesia. The resulting dilation of the arteriovenous shunts leads to redistribution of heat from the core to the periphery, diminishing the temperature gradient between the two compartments.

Effective pain relief with continuous intrapleural bupivacaine after thoracotomy in infants and children.

The effect of continuous intrapleural bupivacaine on pain relief after lateral thoracotomy was studied in nine infants (< or = 15 kg body weight) and 11 children (> 15 kg body weight). An intrapleural catheter was inserted under direct vision during surgery. After extubation, the patients were transferred to the ICU where vital signs and pain scores were monitored.

Hemodynamic and analgesic effects of clonidine added repetitively to continuous epidural and spinal blocks.

Clonidine in spinal and epidural blocks prolongs anesthesia, but can cause hypotension and bradycardia. The aim of our study was to compare hemodynamic and analgesic effects of spinal versus epidural clonidine alone and after repetitive dosing. In a prospective, randomized, double-blind study, we evaluated 40 patients scheduled for lower extremity orthopedic surgery under continuous spinal or epidural anesthesia with bupivacaine 0.

The threshold for thermoregulatory vasoconstriction during nitrous oxide/isoflurane anesthesia is lower in elderly than in young patients.

Background: Thermoregulatory vasoconstriction minimizes further core hypothermia during anesthesia. Elderly patients become more hypothermic during surgery than do younger patients, and take longer to rewarm postoperatively. These data indicate that perianesthetic thermoregulatory responses may be especially impaired in the elderly.