Compromiso de conciencia y bradicardia / Unconciousness and bradycardia

Resumen: Mujer de 71 años, institucionalizada con antecedentes de esquizofrenia y tabaquismo. Consulta en el servicio de urgencias tras ser encontrada a la intemperie comprometida de conciencia. Al llegar la ambulancia se constata mal perfundida, bradipsíquica y bradicárdica, siendo trasladada al servicio de Urgencia. A su ingreso el ECG mostró bradicardia sinusal con trastorno de la conducción intraventricular y prolongación del intervalo QT. Los exámenes de laboratorio al ingreso resultaron dentro de límites normales. La historia clínica y los trazados electrocardiográficos son presentados, siendo discutidos junto al manejo médico.

Abstracts: A 71year old woman, institutionalized with a history of schizophrenia and smoking. She was transported to a local emergency room after being found laying outside unconscious. She was hypoperfused, bradypsychic and bradycardic, being transferred to the emergency service. On admission, the ECG showed sinus bradycardia with intraventricular conduction delay and QT prolongation. Laboratory tests were normal. Clinical history, physical examination and ECG tracings are presented and management is discussed.

Alteraciones electrocardiográficas en hipotermia severa accidental: Caso clínico y revisión de la literatura / Electrocardiographic manifestations of severe accidental hypothermia: Report of one case

We report a 77-year-old female patient who was admitted to the Emergency Department with impairment of consciousness, hypotension, bradycardia and hypothermia. She required endotracheal intubation and transfer to Intensive Care Unit (ICU). Computed tomography of the brain showed no lesions. Electrocardiogram showed abnormalities suggestive of severe hypothermia (bradycardia, marked elevation of J point associated with ST depression, a negative T wave in V2 to V6 and prolongation of QTc), which was confirmed with a pulmonary artery catheter. Myxedema coma, infections and neurological diseases were discarded. The cause of severe hypothermia was unclear, and the probable source was suspected to be accidental. After intensive treatment the patient improved, achieving normalization of electrocardiographic changes, recovery of organic functions and she was discharged home after 22 days.

The Influence of Hypothermia on Transfusion Requirement in Patients Who Received Clopidogrel in Proximity to Off-Pump Coronary Bypass Surgery

PURPOSE: Hypothermia adversely affects the coagulation that could be of clinical significance in patients receiving clopidogrel. We evaluated the influence of hypothermia on transfusion requirements in patients undergoing isolated off-pump coronary artery bypass surgery (OPCAB) who continued clopidogrel use within 5 days of surgery. MATERIALS AND METHODS: Protocol-based, prospectively entered data of 369 patients were retrospectively reviewed. The time-weighted average of intraoperative temperatures and the temperature upon ICU admission (TWA-temp) was assessed. Patients were divided into normothermia (> or =36degrees C, n=224) and hypothermia (<36degrees C, n=145) group. The transfusion requirement for perioperative blood loss was assessed and compared. RESULTS: Patients with hypothermia were older and had lower body surface area (BSA) than patients with normothermia. Age and BSA adjusted transfusion requirement was significantly larger in the hypothermia group [patients requiring transfusion: 64% versus 48%, p=0.003; number of units: 0 (0-2) units versus 2 (0-3) units, p=0.002]. In multivariate analysis of predictors of perioperative multiple transfusion requirements, hypothermia was identified as an independent risk factor along with age, female gender, BSA, chronic kidney disease, and congestive heart failure. CONCLUSION: Hypothermia was associated with increased transfusion requirement in patients undergoing OPCAB who received clopidogrel in proximity to surgery. Considering the high prevalence and the possibility of hypothermia being a modifiable risk factor, aggressive measures should be undertaken to maintain normothermia in those patients.

Neonatal Hypothermia in Sub-Saharan Africa: A Review

Background: Hypothermia is a major factor in neonatal morbidity and mortality in developing countries. High prevalence of hypothermia has been reported widely even from warmer tropical countries. In spite of the World Health Organization's recommendation of maintenance of warm chain in newborn care; hypothermia continues to be a common neonatal condition which has remained under-recognized; under-documented; and poorly-managed. Objective: This review aims at providing the incidence of and risk factors for neonatal hypothermia as well as provides a pathophysiological overview and management options for neonates with the condition in sub-Saharan Africa. Materials and Methods: All available published literature on neonatal hypothermia was searched electronically and manually. The principal electronic reference libraries and sites searched were PubMed; Embase; Ajol; Cochrane Reference Libraries and Google Scholar. The search terms used included 'neonatal hypothermia;' 'Cold stress in newborn' 'thermal care of the newborn;' 'neonatal thermogenesis;' 'neonatal cold injury;' among others. Pertinent books and monographs were accessed. Data in formats inaccessible to the reviewer were excluded. Result and Conclusion: Neonatal hypothermia is a major condition of public health importance in countries of sub- Saharan Africa. Awareness of the burden of the disease is still low in some communities. Risk factors for neonatal hypothermia in the region include poverty; home delivery; low birthweight; early bathing of babies; delayed initiation of breastfeeding and inadequate knowledge among health workers. Low-tech facilities to prevent heat losses and provide warmth are available in sub-Saharan Africa and are thus recommended as well as continuous efforts at sensitizing caregivers on the thermal needs of newborns

Cirurgia para controle de danos: breve revisão / Damage control surgery: a brief review

A cirurgia de controle de dano é processo de preservação do paciente politraumatizado. É concebida como método cirúrgico que surgiu com a necessidade de restaurar a fisiologia normal do paciente vítima de múltiplos traumas e o objetivo de reduzir a mortalidade relacionada ao tratamento cirúrgico definitivo. A "tríade da morte", caracterizada por hipotermia, acidose metabólica e coagulopatia, é a perturbação fisiológica temida na abordagem cirúrgica de politraumatizados. A melhora nas taxas de sobrevida após o advento da cirurgia de controle de danos, entretanto, ainda convive com taxas de mortalidade, em torno de 50%. É procedimento dispendioso e que exige preparação dos centros e equipes que irão receber esses pacientes. Dessa maneira, muitos estudos têm especulado a possibilidade de predizer a evolução de pacientes candidatos a esse tipo de intervenção, a fim de evitar a aplicação de procedimento tão dispendioso em pacientes sem chances de sobreviver. (AU)

The Damage Control Surgery is a process for the preservation of the polytraumatized patient. It was developed due to the need for restore the physiology of such patients back to their normal condition, in order to reduce the mortality rates related to the definitive surgical approach. The "triad of death" hypothermia, acidosis and coagulopathy is a major threat concerning the surgical approach for the trauma patients. Despite the improvements on the survival rates following the introduction of the Damage Control Surgery, the published data show mortality rates circa 50%. Moreover, it is a costly intervention which demands well-prepared teams and trauma centers. Thus, many studies have sought the capacity of predicting the outcome of patients candidates to this procedure, in order to avoid excessive spending with patients who have no chance of survival. (AU)

Fluid heating system (SAF®): effects on clinical and biochemistry parameters in dogs submitted to inhalatory anesthesia / Sistema de aquecimento de fluidos (SAF®): efeitos sobre parâmetros clínicos e bioquímica sérica em cadelas sob anestesia inalatória

PURPOSE: To evaluate and describe immediate effects of the infusion of saline solution heated by SAF® in bitches submitted to halothane anesthesia. METHODS: Thirteen bitches were employed and submitted to elective ovariohysterectomy in acclimatized operating room at 22ºC, allocated in two groups: GI, which received non-heated fluid and GII, which received fluid heated at 37ºC by SAF®. The following parameters were evaluated in 30-minutes intervals (M0, M30, M60 and M90): rectal and cutaneous temperatures (TR and TC), cardiac and respiratory frequencies (HR and ƒ), mean arterial blood pressure (MAP), serum concentration of urea, creatinin, serum activities of alanin aminotranspherasis (ALT), alkaline phosphatasis (ALP) and also hypnosis parameters. RESULTS: There were no significant alterations on clinical and biochemical, but there was group effect on mean arterial blood pressure, urea, ALT, ALP and hypnosis parameters. CONCLUSION: The isolated use of Fluid Heating System (SAF®) was not enough to avoid hypothermia or lead to significant clinical and biochemical alterations in bitches submitted to halothane anesthesia.

OBJETIVO: Avaliar e descrever os efeitos imediatos da infusão de solução salina 0,9 por cento aquecida pelo SAF® sobre cadelas sob anestesia inalatória. MÉTODOS: Foram utilizadas 13 cadelas submetidas a ovariohisterectomia eletiva em centro cirúrgico climatizado a 22ºC, divididas em dois grupos: GI, que recebeu fluido em temperatura ambiente e GII, que recebeu fluido aquecido a 37ºC pelo SAF®. Os parâmetros clínicos avaliados em intervalos de 30 minutos (M0, M30, M60 e M90) foram: temperatura retal (TR) e cutânea (TC), freqüências cardíaca (FR) e respiratória (ƒ), pressão arterial média (PAM), tempo de hipnose, concentrações séricas de uréia e creatinina e atividades das enzimas séricas alanina aminotransferase (ALT) e fosfatase alcalina (ALP). RESULTADOS: Não foram evidenciadas alterações clínicas e bioquímicas significativas, mas houve efeito de grupo sobre as variáveis PAM, uréia, ALT, ALP e tempo de hipnose. CONCLUSÃO: O uso isolado do Sistema de Aquecimento de Fluidos (SAF®) não foi suficiente para evitar o estabelecimento da hipotermia em cadelas submetidas a anestesia geral inalatória, ou promover alterações clínicas e bioquímicas significativas.

Risk of hypothermia in a new olympic event: the 10-km marathon swim

INTRODUCTION: There are no available data addressing the potential clinical risks of open-water swimming competitions. OBJECTIVE: Address the risks of hypothermia and hypoglycemia during a 10-km open-water swimming competition in order to alert physicians to the potential dangers of this recently-introduced Olympic event. METHODS: This was an observational cross-sectional study, conducted during a 10-km open-water event (water temperature 21ºC). The highest ranked elite open-water swimmers in Brazil (7 men, 5 women; ages 21±7 years old) were submitted to anthropometrical measurements on the day before competition. All but one athlete took maltodextrine ad libitum during the competition. Core temperature and capillary glycemia data were obtained before and immediately after the race. RESULTS: Most athletes (83 percent) finished the race with mild to moderate hypothermia (core temperature <35ºC). The body temperature drop was more pronounced in female athletes (4.2±0.7ºC vs. male: 2.7±0.8ºC; p=0.040). When data from the athlete who did not take maltodextrine was excluded, capillary glycemia increased among athletes (pre 86.6±8.9 mg/dL; post 105.5±26.9 mg/dL; p=0.014). Time to complete the race was inversely related to pre- competition body temperature in men (r=-0.802; p=0.030), while it was inversely correlated with the change in capillary glycemia in women (r=-0.898; p=0.038). CONCLUSION: Hypothermia may occur during open-water swimming events even in elite athletes competing in relatively warm water. Thus, core temperature must be a chief concern of any physician during an open-water swim event. Capillary glycemia may have positive effects on performance. Further studies that include more athletes in a controlled setting are warranted.

Oxidative stress is enhanced by hypothermia imposed on cerulein-induced pancreatitis in rats

BACKGROUND: Hypothermia is a frequent event in severe acute pancreatitis (AP) and its real effects on the normal pancreas have not been well demonstrated. Moreover, neither have its effects on the outcome of acute pancreatitis been fully investigated. One hypothesis is that oxidative stress may be implicated in lesions caused or treated by hypothermia. AIM OF THE STUDY: To investigate the effect of hypothermia in cerulein-induced acute pancreatitis (CIAP) in rats and the role played by oxidative stress in this process. METHODS: Male Wistar rats were divided into hypothermic and normothermic groups. Hypothermia was induced with a cold mattress and rectal temperature was kept at 30°C for one hour. Acute pancreatitis was induced with 2 doses of cerulein (20 ìg/kg) administered at a one-hour interval. Serum amylase, pancreas vascular permeability by Evan's blue method, pancreas wet-to-dry weight ratio and histopathology were analyzed in each group. RESULTS: When compared with normothermic rats, hypothermic animals, with cerulein-induced acute pancreatitis, showed higher levels of pancreatic vascular permeability (p < 0.05), pancreas wet-to-dry weight ratio (p = 0.03), and histologically verified edema (p < 0.05), but similar serum amylase levels. The hypothermic group showed a higher oxidized-reduced glutathione ratio than the normothermic group. CONCLUSION: Moderate hypothermia produced a greater inflammatory response in established acute pancreatitis induced by cerulein in rats. Moreover, this study suggests that oxidative stress may be one of the mechanisms responsible for the worse outcome in hypothermic rats with cerulein-induced acute pancreatitis.

BACKGROUND: Hipotermia é um evento freqüente em episódios de pancreatite aguda, contudo seu efeito real sobre pâncreas normal ainda não esta bem demonstrado. Além do mais, o efeito da hipotermia no decorrer da pancreatite aguda também não está completamente esclarecido. Uma das hipóteses sobre as causas das lesões causadas ou tratadas por hipotermia aventa a implicação de estresse oxidativo. OBJETIVOS: Investigar o efeito da hipotermia em ratos com pancreatite aguda induzida por ceruleína e o papel do estresse oxidativo neste processo. MÉTODOS: Ratos Wistar machos foram divididos em grupos hipotérmicos e normotérmicos. Hipotermia foi induzida com uma bolsa gelada de forma que a temperatura retal permanecesse em 30°C por uma hora. Pancreatite aguda foi induzida com duas aplicações de ceruleína (20 ìg/kg) administradas com intervalo de uma hora. A amilase sérica, a permeabilidade vascular do pâncreas, a razão peso seco/peso úmido do pâncreas, a histopatologia e os níveis de glutationa foram analisados em cada grupo. RESULTADOS: Ratos hipotérmicos, com pancreatite aguda induzida por ceruleína, apresentaram maiores níveis de permeabilidade vascular no pâncreas (p < 0.05), razão peso seco/peso úmido do pâncreas (p = 0.03), e edema histológico (p < 0.05), mas os níveis de amilase sérica permaneceram iguais aos níveis apresentados pelos ratos normotérmicos. O grupo hipotérmico apresentou maior relação glutationa oxidada/glutationa reduzida em relação ao grupo normotérmico. CONCLUSÃO: Hipotermia moderada produziu uma maior resposta inflamatória em ratos com pancreatite aguda estabelecida, induzida por ceruleína, sugerindo que este efeito pode estar ligado a um maior índice de estresse oxidativo em ratos com pancreatite aguda.

Manejo del abdomen abierto: experiencia en el Hospìtal "Jesús Yerena" de Lidice / Management of the abdomen: experience in the Hospital \"Jesus Yerena\" de Lidice

Analizar el manejo de pacientes con abdomen abierto, para establecer las pautas con respecto a las indicaciones, técnica quirúrgica utilizada y relaparotomías. Hospital General Dr. Jesús Yerena de Lidice. Servicio de Cirugía General. Estudio de tipo retrospectivo basado en la revisión de historias médicas, de 50 pacientes tratados con abdomen abierto, entre mayo de 1997 y mayo de 2002. Del total de pacientes estudiados; 42 fueron del sexo masculino y 8 del sexo femenino, la edad promedio fue de 38,9 años (Rango: 15-82 años). El 50 por ciento de estos pacientes ingresaron por presentar trauma abdominal, 30 por ciento por infección abdominal, y 20 por ciento por otras causas. Las indicaciones para el manejo abierto del abdomen fueron: Líquido purulento en cavidad (54 por ciento), aumento de la presión intraabdominal (10 por ciento), compromiso vascular de las asas (4 por ciento), empaquetamiento intraabdominal (8 por ciento), pancreatitis (16 por ciento), fístulas intestinales (8 por ciento). La bolsa de Bogotá fue el método más utilizado, para el manejo abierto del abdomen. En total se realizaron 251 intervenciones en 50 pacientes, siendo lo más frecuente de 2 a 3 laparotomías por paciente (rango 1-15 laparotomías), con un intervalo promedio entre cada laparotomía de 24-48 horas. Fallecieron un total de 18 pacientes. El manejo abierto del abdomen, está indicado en pacientes que necesitan más de 2 laparotomías, como en procesos infecciosos severos, en la cirugía de control de daños, en pacientes con presión intraabdominal elevada, pacientes con packing intraabdominal y cuando es necesaria la revisión de la viabilidad de las asas, sometidas a compromiso vascular en la intervención inicial. El abdomen debe cerrarse definitivamente cuando se evidencia resolución de la patología intraabdominal, y se comprueba que no hay contenido purulento dentro del abdomen. La morbi-mortalidad de éstos pacientes aumenta según el número de laparotomías, y el tiempo que permanece.

Effect of Induced and Spontaneous Hypothermia on Survival Time of Uncontrolled Hemorrhagic Shock Rat Model

We examined the hypothesis that mild hypothermia (rectal temperature 34 degrees C) results in the same survival time, whether induced spontaneously or intentionally, during untreated, lethal, uncontrolled hemorrhagic shock in rats. Sixty-four Sprague-Dawley male rats were randomly assigned to normothermia (Nth) (n=19), spontaneous mild hypothermia (Sp.Hth) (n=25) or controlled mild hypothermia (Con.Hth) (n=20) groups. After blood withdrawal of 3 mL/100 g over 15 minutes, followed by 75% tail amputation under spontaneous breathing and light anesthesia by i.p. injection of pentobarbital sodium, rats were observed without fluid resuscitation or hemostasis for 180 minutes or until death. The initial temperature of the Nth group was artificially maintained throughout the experiment. For the mild hypothermia groups, the Sp.Hth group was exposed to ambient temperature while the Con. Hth group was actively cooled to a target rectal temperature of 34 degrees C. In the Con.Hth group, all rats except one died before 180 minutes. All rats in the Nth group died within 38 minutes, and within 67 minutes in the Sp.Hth group. The average survival time was shortest in the Nth group at 20.3 +/- 5.3 minutes, followed by the Sp.Hth group at 30.1 +/- 13.5 minutes, and the Con.Hth group at 81.9 +/- 39.8 minutes (p 0.01). Tail bleed out volume was 0.51 +/- 0.19, 0.26 +/- 0.15 and 0.19 +/- 0.12 mL/100 g in the Nth, Sp.Hth and Con.Hth groups, respectively (p 0.05). In conclusion, spontaneous mild hypothermia did not prolong the survival time as much as controlled mild hypothermia in the rat model for untreated, lethal, uncontrolled hemorrhagic shock.

Role of nitric oxide in hypoxia-induced hyperventilation and hypothermia: participation of the locus coeruleus

Hypoxia elicits hyperventilation and hypothermia, but the mechanisms involved are not well understood. The nitric oxide (NO) pathway is involved in hypoxia-induced hypothermia and hyperventilation, and works as a neuromodulator in the central nervous system, including the locus coeruleus (LC), which is a noradrenergic nucleus in the pons. The LC plays a role in a number of stress-induced responses, but its participation in the control of breathing and thermoregulation is unclear. Thus, in the present study, we tested the hypothesis that LC plays a role in the hypoxia-induced hypothermia and hyperventilation, and that NO is involved in these responses. Electrolytic lesions were performed bilaterally within the LC in awake unrestrained adult male Wistar rats weighing 250-350 g. Body temperature and pulmonary ventilation (VE) were measured. The rats were divided into 3 groups: control (N = 16), sham operated (N = 7) and LC lesioned (N = 19), and each group received a saline or an NG-nitro-L-arginine methyl ester (L-NAME, 250 µg/µl) intracerebroventricular (icv) injection. No significant difference was observed between control and sham-operated rats. Hypoxia (7 per cent inspired O2) caused hyperventilation and hypothermia in both control (from 541.62 + or - 35.02 to 1816.18 + or - 170.7 and 36.3 + or - 0.12 to 34.4 + or - 0.09, respectively) and LC-lesioned rats (LCLR) (from 694.65 + or - 63.17 to 2670.29 + or - 471.33 and 36 + or - 0.12 to 35.3 + or - 0.12, respectively), but the increase in VE was higher (P<0.05) and hypothermia was reduced (P<0.05) in LCLR. L-NAME caused no significant change in VE or in body temperature under normoxia, but abolished both the hypoxia-induced hyperventilation and hypothermia. Hypoxia-induced hyperventilation was reduced in LCLR treated with L-NAME. L-NAME also abolished the hypoxia-induced hypothermia in LCLR. The present data indicate that hypoxia-induced hyperventilation and hypothermia may be related to the LC, and that NO is involved in these responses.

Thermal, cardiovascular & thermogenic responses to mild cold exposure in chronically energy deficient human subjects.

Thirteen young, male adults were investigated for thermal, cardiovascular and metabolic responses to truncal cooling for 40 min. The subjects were divided into two groups [well nourished controls (WN) and chronically energy deficient (CED)] on the basis of anthropometry and socio-economic status. The CED group had significantly greater reductions in peripheral forearm blood flow and surface finger tip temperatures on exposure to cold when compared to the well nourished controls. The CED group also showed a significant rise in oxygen consumption (3.4%), while no thermogenic response was observed in the WN controls. There was no fall in deep body temperature in either group. The study suggests that chronically energy deficient subjects thermoregulate appropriately on exposure to mild cold. The deficiency in insulative body fat is made up for by evoking greater peripheral vasoconstrictor responses as well as thermogenic mechanisms. The study suggests that on exposure to cold, thermoregulation takes precedence over energy conservation in chronically energy deficient subjects.

Hipotermia accidental / Accidental hypothermia

La hipotermia accidental presenta una elevada tasa de mortalidad, que oscila entre 2,2 a 18,1 por millón de habitantes de acuerdo a los diferentes medios. A propósito de cuatro casos de hipotermia accidental se analizan sus caracteres clínicos, diagnósticos, terapéuticos y pronósticos

Oxygen as a modulator of body temperature

Most animals respond to a shortage of oxygen by lowering their body temperature. This response, mediated by behavior and physiological means, reduces oxygen demand via the Q10 effect, and should therefore be adaptive. This article reviews the occurrence of this response within the animal kingdom, the possible mechanisms and mediators of the response, and the physiological significance of hypoxia-induced hypothermia.

Hipotermia: una indicación no renal para la diálisis peritoneal / Hipothermia: a non renal indication for peritoneal dialysis

Accidental hypothermia, a condition seldomly seen in Chile, is defined as a spontaneous core temperature reduction to less than 35§ C and is associated with great morbidity and mortality. We report a 16 years old female intoxicated with liquefied petroleum gas that was admitted in coma, hypothermic, with severe hemodynamic derangement, lactic acidosis, rhabdomyolysis and iliofemoral phlebothrombosis. Peritoneal dialysis with solutions at 27§ C was used as a quick and safe means to revert hypothermia and avoid its complications