The intensity of postoperative shivering is unrelated to axillary temperature

Abstract

SummaryThe relationship between axillary temperature and postoperative shivering was examined in 302 patients who entered one recovery room in the Derbyshire Royal Infirmary over a one-month period. No relationship was found between temperature and the occurrence of shivering, or between conscious level and the occurrence of shivering. Key wordsTemperature; body, regulation. Complications; shivering.Postoperative shivering is distressing for the patient and may impair the quality of recovery from anaesthesia by increasing oxygen consumption and thereby causing hypoxaemia and lactic acidosis [1-4]. It has been noted repeatedly that shivering after general anaesthesia correlates poorly with body temperature although Vaughan and colleagues [8] reported that patients who entered the recovery room with an axillary temperature less than 36°C shivered for longer than those who were warmer. In a previous study [lo], we were unable to confirm these reports because of the study design.In most studies, there has been little attempt to standardise the classification of postoperative shivering, and this omission has led to difficulty in the interpretation of otherwise comparable investigations. We have devised a simple clinical grading scale for postoperative shivering which we have applied to patients recovering from general anaesthesia. The results reported here are derived from a larger study of recovery parameters which will be reported separately. MethodsData relating to various parameters relevant to recovery from general anaesthesia were collected from 302 patients over a one-month period. The data were collected by the recovery room nurses on entry of the patient into the recovery room, after 15 min, and again 30 min after entry, and included grade of shivering (Table 1) and axillary temperature measured using a mercury-in-glass clinical thermometer. Conscious level (Table 2), pain score, nausea and vomiting and various ventilatory and cardiovascular parameters were also recorded.The data were combined with information about anaesthetic technique collected using the Derby Anaesthetic Audit System [ll]. Statistical analysis was by paired Student's t-test, analysis of variance, Mann-Whitney U test and the Chi-squared test where appropriate, and was performed using the SPSS-PC+ statistical package. A probability of p < 0.05 was taken as indicating statistical significance.

Tremores intra e pós-operatório: prevenção e tratamento farmacológico

“…Therefore, it is reasonable to assume that, in the absence of a surgical procedure, hypothermia contributes for the development of tremors and that normothermia protects against it 12 . The study demonstrated that core temperature had only a slight influence on the development of tremors when compared with age (most important factor), and was compatible with the results of other studies that demonstrated that temperature has a weak predictive power for the development of tremors 36,37 . According to the analysis of multifactorial logistic regression, core temperature was not directly related with postoperative tremors in children, while the relative change of perioperative temperature was one of three independent predictors 38 .…”

“…É, portanto, razoável presumir que a hipotermia contribui para tremor e que a normotermia é protetora, na ausência de intervenção cirúrgica 12 . O estudo demonstrou que a temperatura central teve apenas uma leve influência no desenvolvimento de tremores comparada com a idade (fator mais determinante) e foi compatível com resultados de outros estudos que mostraram que a temperatura tem um fraco poder preditivo para tremor 36,37 . De acordo com a análise de regressão logística multifatorial a temperatura central não foi diretamente relacionada com tremores pós-operatórios em crianças, enquanto a mudança relativa de temperatura perioperatória foi um dos três preditores independentes 38 .…”

“…O grau dos tremores foi avaliado e classificado de acordo com uma escala qualitativa no artigo de Crossley e Mahajan 36 : 0 = sem tremor; 1 = sem atividade muscular visível, mas com piloereção, vasoconstrição periférica ou ambos; 2 = atividade muscular em apenas um grupo muscular; 3 = atividade muscular moderada em mais de um grupo muscular mas sem tremor generalizado; e 4 = atividade muscular violenta envolvendo todo o corpo.…”

“…The degree of tremors was evaluated and classified according to a qualitative scale in the work of Crossley and Mahajan 36 : 0 = without tremor; 1 = without visible muscular activity but with piloerection, peripheral vasoconstriction, or both; 2 = muscular activity affecting only one muscle group; 3 = moderate muscular activity involving more than one muscle group, but without generalized tremors; and 4 = severe muscular activity involving the entire body.…”

Efficacy of prophylactic epidural ketamine for reducing shivering in patients undergoing caesarean section with combined spinal‑epidural anesthesia

“…Exclusion criteria were as follows: History of severe cardiovascular complications, preoperative temperature >38˚C or <35˚C, any contraindications to regional anesthesia, ketamine allergy, preeclampsia, diabetes mellitus, significant peripartum hemorrhage or the existence of an absolute or relative contraindication for the application of the epidural technique, including neuromuscular disease, bleeding tendency or local skin infection in the lumbar region. A previous study (14) reported that intraoperative shivering is not associated with intraoperative temperature. The intraoperative room temperature and the temperature of the infusion liquid were controlled and, although the intraoperative temperature was monitored during the present study, it was not included as a detection index.…”