Cooling methods for paediatric heat-induced illnesses

• Published in: Archives of disease in childhood Vol. 106; no. 4; pp. 405 - 406
• Main Authors: Jamal, Dried, Abdelgadir, Ibtihal, Powell, Colin V E
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health 01.04.2021; BMJ Publishing Group LTD
• Subjects: Adults; Archimedes; Bias; Blood flow; Body Composition; Body temperature; Children & youth; Climate; Cold; Disseminated intravascular coagulation; Edema; Emergency medical care; Epidemiology; Evaporation; Evidence; Fever; Heat; Heatstroke; Hepatic encephalopathy; Heterogeneity; Hyperthermia; Ice; Immersion; Medical prognosis; Meta Analysis; Morbidity; mortality; Oxidative phosphorylation; Passive cooling; Patients; Pediatrics; Phosphorylation; Population; Population studies; resuscitation; Scientific Concepts; Seizures; Sepsis; Skin; Survival; Systematic review; Temperature; Temperature gradients; therapeutics; Trauma; Vasoconstriction; Water; mortality; epidemiology; resuscitation; therapeutics
• ISSN: 0003-9888; 1468-2044; 1468-2044
• DOI: 10.1136/archdischild-2020-319905

Clinical question In [children presenting with heat-induced illnesses] is [cold/ice water immersion more effective than evaporation technique/passive cooling] at [reducing body temperature]? A total of 112 unique records were identified, and 8 were included.1–8 Three reviews were considered relevant and are presented in table 1.1 2 7 Table 1 Summary of main studies Citation, date Study group Study type Intervention Key results and outcome Study weakness/comments Bouchama et al 20072 19 studies 556 adults Exertional heatstroke and classic heatstroke Systematic review CWI to conductive cooling and evaporative techniques IWI was superior to other methods in cooling rate but with higher mortality and morbidity Systematic review taking evidence from case series No specific comment about bias and grade of evidence but comments of lack of reliability, small study numbers, heterogeneity Demartini et al 20151 274 adults, age 34±3 years Case reviews CWI (10°C) within 30 min of the diagnosis ‘Golden half hour’ Cooling rate: 0.22°C/min±0.11°C/min Survival rate 100% Case reviews only Low-grade evidence Zhang et al 20157 19 studies 233 adults Healthy exertional heat stroke Meta-analysis CWI compared with passive recovery CWI twice as fast as passive cooling Mean difference 0.03°C/min (95% CI 0.03 to 0.04) Variable immersion levels: hands only to total body Risk of bias assessed by PEDRo score (0–10) all papers 7–8 except one of high risk of bias score 4 Heterogeneity 94.5% PEDro: Physiotherapy Evidence Database scale.8 CWI, cold water immersion, usually 10ºC (1ºC–15ºC); IWI, ice water immersion. The effectiveness of cooling modalities is based on the cooling rate: ideal cooling modalities provide a cooling rate equal to or higher than 0.2°C/min.7 Best prognosis and outcome are directly related to the initiation of rapid cooling during the first hour after collapse; thus, the term ‘Golden hour’ that applies to sepsis and trauma is also applied to the management of heat-related illnesses.11 It is thus important to early recognise and prompt manage heat-related illness.1 9–13 This paper will focus on two cooling methods that are widely used for the management of heat-related illness: cold/ice water immersion and evaporation technique/passive cooling.2 These two methods have been proven to be effective in heat dissipation by increasing the temperature gradient between the skin and the environment without compromising the blood flow to the skin.14 Most of the studies have examined adults, and there are limited data on paediatrics.15 In cases of children affected by heat-related illnesses, the same adult cooling techniques were used.12 Several non-invasive cooling methods have been discussed in the studies; each has a specific cooling rate. Other methods (body cooling units, EMCOOLS flex pad and Thermo suit) use similar physical mechanisms.1 4–8 16 IWI shows a high cooling rate among other methods with fair size sample population being studied, and CWI/IWI proved to be a safer yet rapid way to treat hyperthermia within the golden 1 hour to avoid long-term complications.1 7 Immersion techniques have also been challenging due to speculation that shivering can induce cardiac arrhythmias and vasoconstriction may lead to an increase in body core temperature.6 13 Evaporative techniques use wet towels or sponging with cold water at various degrees.