Time and Obstetric Anesthesia: from Chaotic Cosmology to Chronobiology

Circadian effects on neural blockade of levobupivacaine and fentanyl intrathecal administration for caesarian section

“…Specific obstetrical factors (stage of cervical dilation, and pharmacological induction of uterine contractions and their frequency) and other factors such as age, parity, previous caesarean sections, could complicate the assessment of the postoperative pain. 4,12 The strength of our study is the attempt to minimize the impingement of parameters that affect circadian rhythmicity by enrolling patients with common everyday lifestyle and regular feeding and sleeping schedule, and by performing the study in the same season in order to better detect endogenous rhythms. The limitations of our study included the lack of synchronization of the subjects' circadian time organization by not checking cortisol or melatonin plasma levels (rhythm markers), or the identification of an individual's innate circadian phenotype.…”

“…[5][6][7][8]13 Although only two studies reported that time of day did not appear to influence the duration of analgesia during labour produced by intrathecal local anaesthetics or opioids 9,10 , the results of most studies were able to produce a consistent picture with peaks in the morning or at noon. 4,5,7,8 The pharmacological effect regarding intrathecal or epidural administration of local anaesthetics was longer in the diurnal period 4,8,13 , and the latency period was longer at night 6 . A temporal pattern in the duration of analgesia with a peak around noon 5,7,8 was also observed.…”

“…Pharmacokinetics and pharmacodynamics of local anaesthetics are subject to circadian variations, profoundly affecting their efficacy and toxicity. [1][2][3][4] In order to establish if neuraxial local anaesthetics present time-dependent effects, numerous chronobiological studies were conducted in labour pain analgesia. [5][6][7][8]13 Although only two studies reported that time of day did not appear to influence the duration of analgesia during labour produced by intrathecal local anaesthetics or opioids 9,10 , the results of most studies were able to produce a consistent picture with peaks in the morning or at noon.…”

Being born at home is natural: care rituals for home birth

“…Aromatherapy through the lavender oil, another care ritual we observed, can be justified by its soothing and calming action; music therapy is able to intervene in the cycle of fear and tension, providing relaxation and minimizing the pain (6) ; on the other hand, high intensity electric lamps are associated with reduced levels of melatonin, the hormone that generates stress and increases the pain, justifying the importance of low light at childbirth (17) .…”