Red hair and anesthetic requirement

Background Age and body temperature alter inhalational anesthetic requirement; however, no human genotype is associated with inhalational anesthetic requirement. There is an anecdotal impression that anesthetic requirement is increased in redheads. Furthermore, red hair results from distinct mutations of the melanocortin-1 receptor. Therefore, the authors tested the hypothesis that the requirement for the volatile anesthetic desflurane is greater in natural redheaded than in dark-haired women. Methods The authors studied healthy women with bright red (n = 10) or dark (n = 10) hair. Blood was sampled for subsequent analyses of melanocortin-1 receptor alleles. Anesthesia was induced with sevoflurane and maintained with desflurane randomly set at an end-tidal concentration between 5.5 and 7.5%. After an equilibration period, a noxious electrical stimulation (100 Hz, 70 mA) was transmitted through bilateral intradermal needles. If the volunteer moved in response to stimulation, desflurane was increased by 0.5%; otherwise, it was decreased by 0.5%. This was continued until volunteers "crossed over" from movement to nonmovement (or vice versa) four times. Individual logistic regression curves were used to determine desflurane requirement (P50). Desflurane requirements in the two groups were compared using Mann-Whitney nonparametric two-sample test; P < 0.05 was considered statistically significant. Results The desflurane requirement in redheads (6.2 vol% [95% CI, 5.9-6.5]) was significantly greater than in dark-haired women (5.2 vol% [4.9-5.5]; P = 0.0004). Nine of 10 redheads were either homozygous or compound heterozygotes for mutations on the melanocortin-1 receptor gene. Conclusions Red hair seems to be a distinct phenotype linked to anesthetic requirement in humans that can also be traced to a specific genotype.

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Increased Anesthetic Requirement in Subjects with Naturally Red Hair

Anesthesiology ◽

10.1097/00000542-200209002-00077 ◽

2002 ◽

Vol 96 (Sup 2) ◽

pp. A77 ◽

Cited By ~ 5

Author(s):

Edwin B. Liem ◽

Chun-Ming Lin ◽

Mohammed I. Suleman ◽

Anthony G. Doufas ◽

Daniel I. Sessler

Keyword(s):

Red Hair ◽

Anesthetic Requirement

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Influence of Body Temperature on Bispectral Index-Guided Anesthetic Management in Off-Pump Coronary Artery Bypass Grafting

Journal of Cardiac Critical Care TSS ◽

10.1055/s-0040-1718975 ◽

2020 ◽

Vol 4 (02) ◽

pp. 079-085

Author(s):

Muralidhar Kanchi ◽

Priya Nair ◽

Rudresh Manjunath ◽

Kumar Belani

Keyword(s):

Coronary Artery ◽

Body Temperature ◽

Artery Bypass ◽

Anesthetic Depth ◽

Off Pump ◽

Anesthetic Concentration ◽

The Mean ◽

Anesthetic Requirement ◽

Pump Coronary Artery Bypass ◽

End Tidal

Abstract Background Perioperative hypothermia is not uncommon in surgical patients due to anesthetic-induced inhibition of thermoregulatory mechanisms and exposure of patients to cold environment in the operating rooms. Core temperature reduction up to 35°C is often seen in off-pump coronary artery bypass graft (OP-CABG) surgery. Anesthetic depth can be monitored by using bispectral (BIS) index. The present study was performed to evaluate the influence of mild hypothermia on the anesthetic depth using BIS monitoring and correlation of BIS with end-tidal anesthetic concentration at varying temperatures during OP-CABG. Materials and Methods In a prospective observational study design in a tertiary care teaching hospital, patients who underwent elective OP-CABG under endotracheal general anesthesia, were included in the study. Standard technique of anesthesia was followed. BIS, nasopharyngeal temperature, and end-tidal anesthetic concentration of inhaled isoflurane was recorded every 10 minutes. The BIS was adjusted to between 45 and 50 during surgery. Results There were 40 patients who underwent OP-CABG during the study period. The mean age was 51.2 ± 8.7 years, mean body mass index 29.8 ± 2.2, and mean left ventricular ejection fraction was 55.4 ± 4.2%. Anesthetic requirement as guided by BIS between 45 and 50 correlated linearly with core body temperature (r = 0.999; p < 0.001). The mean decrease in the body temperature at the end of 300 minutes was 2.2°C with a mean decrease in end-tidal anesthetic concentration of 0.29%. The reduction in end-tidal anesthetic concentration per degree decrease in temperature was 0.13%. None of the patients reported intraoperative recall. Conclusion In this study, BIS monitoring was used to guide the delivery concentration of inhaled anesthetic using a targeted range of 45 to 50. BIS monitoring allowed the appropriate reduction of anesthetic dosing requirements in patients undergoing OP-CABG without risk of awareness. There was a significant reduction in anesthetic requirements associated with reduction of core temperature. The routine use of BIS is recommended in OP-CABG to titrate anesthetic requirement during occurrence of hypothermia and facilitate fast-track anesthesia in this patient population.

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Reduction in Halothane Anesthetic Requirement by Clonidine, an Alpha-Adrenergic Agonist

Anesthesia & Analgesia ◽

10.1213/00000539-198209000-00005 ◽

1982 ◽

Vol 61 (9) ◽

pp. 741???745 ◽

Cited By ~ 125

Author(s):

Byron C Bloor ◽

Werner E. Flacke

Keyword(s):

Adrenergic Agonist ◽

Anesthetic Requirement ◽

Alpha Adrenergic Agonist

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RED HAIR IN AFRICAN NEGROES: A PRELIMINARY STUDY

Annals of Eugenics ◽

10.1111/j.1469-1809.1953.tb02547.x ◽

1953 ◽

Vol 18 (1) ◽

pp. 211-232 ◽

Cited By ~ 6

Author(s):

N. A. BARNICOT

Keyword(s):

Red Hair ◽

Preliminary Study

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Interaction of Isoflurane and Nitrous Oxide Combinations Similar for Median Electroencephalographic Frequency and Clinical Anesthesia

Anesthesiology ◽

10.1097/00000542-199604000-00004 ◽

1996 ◽

Vol 84 (4) ◽

pp. 782-788. ◽

Cited By ~ 18

Author(s):

Heiko Ropcke ◽

Helmut Schwilden

Keyword(s):

Nitrous Oxide ◽

Minimum Alveolar Concentration ◽

Dose Range ◽

Volatile Anesthetic ◽

Oxide Concentration ◽

Anesthetic Requirement ◽

Clinical Anesthesia ◽

Sparing Effect ◽

The Relationship ◽

Nitrous Oxide Concentration

Background The volatile anesthetic sparing effect of nitrous oxide in clinical studies is less than might be expected from the additivity of minimum alveolar concentration values. Other studies identify nonadditive interactions between isoflurane and nitrous oxide. The aim of this study was to quantify the interaction of isoflurane and nitrous oxide at a constant median electroencephalographic frequency. Methods Twenty-five patients were studied during laparotomies. Nitrous oxide was randomly administered in concentrations of 0, 20, 40, 60, and 75 vol%, to ten patients for each nitrous oxide concentration. Isoflurane vaporizer settings were chosen so that the median electroencephalographic frequency was held between 2 and 3 Hz. The relationship between nitrous oxide concentrations and required isoflurane concentrations was examined with the method of isoboles. Results Nitrous oxide linearly decreased the isoflurane requirement. Addition of every 10 vol% of nitrous oxide decreases the isoflurane requirement by approximately 0.04 vol%. The total anesthetic requirement of isoflurane and nitrous oxide, expressed in terms of previously reported minimum alveolar concentration values, increased significantly with increasing nitrous oxide concentrations. Conclusions The interaction of isoflurane and nitrous oxide in the dose range 0-75 vol% on median electroencephalographic frequency is compatible with additivity. The potency of nitrous oxide as a substitute for isoflurane is less than on a minimum alveolar concentration basis. Maintaining median electroencephalographic frequency more appropriately reflects the clinical usage of isoflurane and nitrous oxide than does maintaining minimum alveolar concentration.

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A cyanine-type homolog of the red hair bibenzothiazine chromophore combining reversible proton-sensing with a hydrophobic-to-hydrophilic switching response

Dyes and Pigments ◽

10.1016/j.dyepig.2021.109872 ◽

2021 ◽

pp. 109872

Author(s):

Maria Laura Alfieri ◽

Lucia Panzella ◽

Orlando Crescenzi ◽

Marco d’Ischia ◽

Alessandra Napolitano

Keyword(s):

Red Hair

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Dermatofluoroscopy Is Also for Redheads a Sensitive Method of Early Melanoma Detection

Dermatology ◽

10.1159/000507614 ◽

2020 ◽

Vol 236 (6) ◽

pp. 508-516

Author(s):

Dieter Leupold ◽

Lukasz Szyc ◽

Goran Stankovic ◽

Maja Hofmann ◽

Matthias Scholz ◽

...

Keyword(s):

Fluorescence Spectra ◽

Spectral Characteristics ◽

Spatially Resolved ◽

Melanoma Detection ◽

Dysplastic Nevi ◽

Red Hair ◽

Pigmented Lesions ◽

Melanoma Diagnosis ◽

Increased Risk ◽

Hair Samples

Background: Caucasians with red hair and fair skin have a remarkably increased risk of malignant melanoma compared to non-redhead Caucasians. Objectives: With the aim of a reliable melanoma diagnosis in redheads, the application of dermatofluoroscopy was analyzed in 16 patients with red hair. Most of them had been included in a clinical dermatofluoroscopy study for patients with the suspicion of melanoma. We examined whether the 25 lesions of the redheads showed the same characteristic melanin fluorescence spectra for dysplastic nevi and melanomas as those of non-redhead Caucasians or whether there was a different fluorescence pattern. This is important in view of the known significantly altered ratio of eumelanin to pheomelanin in the skin of redheads. Methods: More than 8,000 spatially resolved fluorescence spectra of 25 pigmented lesions were measured and analysed. The spectra were excited by the stepwise absorption of two 800-nm photons (principle of dermatofluoroscopy). Furthermore, the fluorescence spectra of eumelanin and pheomelanin in hair samples were determined in the same way. Results: The evaluation revealed that the melanin fluorescence spectra of dysplastic nevi and melanomas of redheads have the same spectral characteristics as those of non-redhead Caucasians. An accompanying result is that dermatofluoroscopy shows identical fluorescence spectra for eumelanin and pheomelanin. Conclusions: Dermatofluoroscopy proves to be a reliable diagnostic method also for redheads. Our results also explain our recent finding that there is a uniform fluorescence spectroscopic fingerprint for melanomas of all subtypes, which is of particular interest for hypomelanotic and apparently amelanotic melanomas containing pheomelanin.

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