1
|
Ramjist JK, Sutthatarn P, Elliott C, Lee KS, Fecteau A. Introduction of a Warming Bundle to Reduce Hypothermia in Neonatal Surgical Patients. J Pediatr Surg 2024; 59:858-862. [PMID: 38388284 DOI: 10.1016/j.jpedsurg.2024.01.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 01/22/2024] [Indexed: 02/24/2024]
Abstract
INTRODUCTION Hypothermia in the neonatal surgical population has been linked with significant morbidity and mortality. Our goal was to decrease intra and postoperative hypothermia. INTERVENTION In November 2021, a radiant warmer and hat were included along with standard warming methods prior to the start of General Surgery procedures to minimize episodes of hypothermia. PRIMARY OUTCOME Core body temperature was measured pre, intra and post-operatively. METHODS Data were prospectively collected from electronic medical records from July 2021 to March 2023. A retrospective analysis was performed. Hypothermia was defined as a temperature <36.5C. Control charts were created to analyze the effect of interventions. RESULTS A total of 277 procedures were identified; 226 abdominal procedures, 31 thoracic, 14 skin/soft tissue and 6 anorectal. The median post-natal age was 36.1 weeks (IQR: 33.2-39.2), with a pre-surgical weight of 2.3 kg (IQR: 1.6-3.0) and operative duration of 181 min (IQR: 125-214). Hat and warmer data were unavailable for 59 procedures, both hat and warmer were used for 51 % procedures, hat alone for 29 %, warmer alone for 10 % and neither for 10 % of procedures. Over time there was a significant increase in hat utilization while warmer usage was unchanged. There was a significant increase in the mean lowest intra-operative temperature and decrease in proportion of hypothermic patients intra-operatively and post-operatively. CONCLUSIONS The inclusion of a radiant warmer and hat decreased the proportion of hypothermic patients during and after surgery. Further studies are necessary to analyze the impact on surgical outcomes. LEVEL OF EVIDENCE III.
Collapse
Affiliation(s)
- Joshua K Ramjist
- Division of General and Thoracic Surgery, The Hospital for Sick Children, Toronto, ON, Canada; Department of General and Thoracic Surgery, Temerty Faculty of Medicine, University of Toronto, ON, Canada
| | - Pattamon Sutthatarn
- Division of General and Thoracic Surgery, The Hospital for Sick Children, Toronto, ON, Canada; Department of General and Thoracic Surgery, Temerty Faculty of Medicine, University of Toronto, ON, Canada
| | - Christine Elliott
- Division of Neonatology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Kyong-Soon Lee
- Division of Neonatology, The Hospital for Sick Children, Toronto, ON, Canada; Department of Paediatrics, Temerty Faculty of Medicine, University of Toronto, ON, Canada
| | - Annie Fecteau
- Division of General and Thoracic Surgery, The Hospital for Sick Children, Toronto, ON, Canada; Department of General and Thoracic Surgery, Temerty Faculty of Medicine, University of Toronto, ON, Canada.
| |
Collapse
|
2
|
Lee C, Lee C, Lee J, Jang G, Kim B, Park S. Comparison of Core Body Temperatures in Patients Administered Remimazolam or Propofol during Robotic-Assisted and Laparoscopic Radical Prostatectomy. MEDICINA (KAUNAS, LITHUANIA) 2022; 58:medicina58050690. [PMID: 35630107 PMCID: PMC9144657 DOI: 10.3390/medicina58050690] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/18/2022] [Accepted: 05/21/2022] [Indexed: 11/23/2022]
Abstract
Background and Objectives: Different types of anesthetics affect thermoregulatory mechanisms, such as the redistribution of body temperature, loss of skin heat, or inhibition of thermoregulatory vasoconstriction. Therefore, we compared remimazolam with propofol in terms of core body temperature in patients undergoing robotic-assisted and laparoscopic radical prostatectomy. Materials and methods: Ninety patients were randomly assigned to either the propofol−remifentanil (PR) group or the remimazolam−remifentanil (RR) group. The PR group (n = 45) received effect-site concentrations of 6.0 μg/mL of propofol and 4 ng/mL of remifentanil, followed by 0.9 mg/kg of 1% rocuronium and maintenance with effect-site concentrations of 2−4 μg/mL of propofol and 3 ng/mL of remifentanil. The RR group (n = 45) received remimazolam 6 mg/kg/h by continuous intravenous infusion and the effect-site concentration of 4 ng/mL of remifentanil, followed by 0.9 mg/kg of 1% rocuronium, remimazolam 1−3 mg/kg/h, and remifentanil 3 ng/mL. The primary outcome was core body temperature, and secondary outcomes included vasoconstriction threshold (°C) and time to onset of vasoconstriction (min). Results: The core body temperature in the RR group was significantly higher at 60, 80, 100, 120, 140, 160, and 180 min after induction than in the PR group (p < 0.01). The vasoconstriction threshold was significantly higher in the RR group (35.2 ± 0.4) than in the PR group (34.8 ± 0.3) (p < 0.01). The time to onset of vasoconstriction was significantly less in the RR group (150.5 ± 10.2) than in the PR group (158.5 ± 8.4) (p < 0.01). However, the incidence of intraoperative hypothermia was not significant between two groups. Conclusions: Remimazolam appears to reduce vasoconstriction threshold less than and had a faster onset of vasoconstriction, resulting in superior thermoregulatory control.
Collapse
Affiliation(s)
- Cheol Lee
- Department of Anesthesiology and Pain Medicine, Wonkwang University School of Medicine Hospital, 895 Muwang-ro, Iksan 54538, Korea; (C.L.); (J.L.); (G.J.)
- Correspondence: (C.L.); (S.P.)
| | - Cheolhyeong Lee
- Department of Anesthesiology and Pain Medicine, Wonkwang University School of Medicine Hospital, 895 Muwang-ro, Iksan 54538, Korea; (C.L.); (J.L.); (G.J.)
| | - Juhwan Lee
- Department of Anesthesiology and Pain Medicine, Wonkwang University School of Medicine Hospital, 895 Muwang-ro, Iksan 54538, Korea; (C.L.); (J.L.); (G.J.)
| | - Gihyeon Jang
- Department of Anesthesiology and Pain Medicine, Wonkwang University School of Medicine Hospital, 895 Muwang-ro, Iksan 54538, Korea; (C.L.); (J.L.); (G.J.)
| | - ByoungRyun Kim
- Department of Obstetrics and Gynecology, Wonkwang University School of Medicine Hospital, 895 Muwang-ro, Iksan 54538, Korea;
| | - SeongNam Park
- Department of Obstetrics and Gynecology, Wonkwang University School of Medicine Hospital, 895 Muwang-ro, Iksan 54538, Korea;
- Correspondence: (C.L.); (S.P.)
| |
Collapse
|
3
|
Van Duren A. Perioperative Prewarming: Heat Transfer and Physiology. AORN J 2022; 115:407-422. [PMID: 35476210 DOI: 10.1002/aorn.13667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 11/19/2021] [Accepted: 12/12/2021] [Indexed: 11/07/2022]
Abstract
To appreciate the strategy of prewarming, perioperative personnel should have a basic understanding of the physics of heat transfer and the thermoregulatory pathophysiology of anesthesia. The dominant cause of postinduction hypothermia is anesthesia-related redistribution of heat within the body; the role of cutaneous heat loss is minimal. Physiologic thermoregulatory system changes that occur in response to anesthesia make it almost impossible to reverse intraoperative hypothermia. However, prewarming is an effective strategy to prevent postinduction hypothermia from redistribution because it creates a temporary excess of heat in the body's peripheral thermal compartment. Perioperative nurses should implement active and passive prewarming strategies in accordance with the warming devices at their facility and available time. This article focuses on two major topics necessary to understand prewarming: the effect of anesthesia on postinduction thermoregulation and thermodynamic conditions that successful treatment strategies must exploit to produce desired outcomes.
Collapse
|
4
|
Rauch S, Miller C, Bräuer A, Wallner B, Bock M, Paal P. Perioperative Hypothermia-A Narrative Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:8749. [PMID: 34444504 PMCID: PMC8394549 DOI: 10.3390/ijerph18168749] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/13/2021] [Accepted: 08/14/2021] [Indexed: 11/25/2022]
Abstract
Unintentional hypothermia (core temperature < 36 °C) is a common side effect in patients undergoing surgery. Several patient-centred and external factors, e.g., drugs, comorbidities, trauma, environmental temperature, type of anaesthesia, as well as extent and duration of surgery, influence core temperature. Perioperative hypothermia has negative effects on coagulation, blood loss and transfusion requirements, metabolization of drugs, surgical site infections, and discharge from the post-anaesthesia care unit. Therefore, active temperature management is required in the pre-, intra-, and postoperative period to diminish the risks of perioperative hypothermia. Temperature measurement should be done with accurate and continuous probes. Perioperative temperature management includes a bundle of warming tools adapted to individual needs and local circumstances. Warming blankets and mattresses as well as the administration of properly warmed infusions via dedicated devices are important for this purpose. Temperature management should follow checklists and be individualized to the patient's requirements and the local possibilities.
Collapse
Affiliation(s)
- Simon Rauch
- Department of Anaesthesiology and Intensive Care Medicine, “F. Tappeiner” Hospital, 39012 Merano, Italy;
- Institute of Mountain Emergency Medicine, Eurac Research, 39100 Bolzano, Italy
| | - Clemens Miller
- Department of Anaesthesiology, University Medical Centre Goettingen, 37075 Goettingen, Germany; (C.M.); (A.B.)
| | - Anselm Bräuer
- Department of Anaesthesiology, University Medical Centre Goettingen, 37075 Goettingen, Germany; (C.M.); (A.B.)
| | - Bernd Wallner
- Department of Anaesthesiology and Intensive Care Medicine, Medical University of Innsbruck, 6020 Innsbruck, Austria;
| | - Matthias Bock
- Department of Anaesthesiology and Intensive Care Medicine, “F. Tappeiner” Hospital, 39012 Merano, Italy;
- Department of Anaesthesiology, Perioperative Medicine and Intensive Care Medicine, Paracelsus Medical University, 5020 Salzburg, Austria
| | - Peter Paal
- Department of Anaesthesiology and Intensive Care Medicine, Hospitallers Brothers Hospital, Paracelsus Medical University, 5010 Salzburg, Austria;
| |
Collapse
|
5
|
Perioperative Hypothermia in Children. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18147541. [PMID: 34299991 PMCID: PMC8308095 DOI: 10.3390/ijerph18147541] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/13/2021] [Accepted: 07/14/2021] [Indexed: 12/15/2022]
Abstract
Background: First described by paediatric anaesthesiologists, perioperative hypothermia is one of the earliest reported side effects of general anaesthesia. Deviations from normothermia are associated with numerous complications and adverse outcomes, with infants and small children at the highest risk. Nowadays, maintenance of normothermia is an important quality metric in paediatric anaesthesia. Methods: This review is based on our collection of publications regarding perioperative hypothermia and was supplemented with pertinent publications from a MEDLINE literature search. Results: We provide an overview on perioperative hypothermia in the paediatric patient, including definition, history, incidence, development, monitoring, risk factors, and adverse events, and provide management recommendations for its prevention. We also summarize the side effects and complications of perioperative temperature management. Conclusions: Perioperative hypothermia is still common in paediatric patients and may be attributed to their vulnerable physiology, but also may result from insufficient perioperative warming. An effective perioperative warming strategy incorporates the maintenance of normothermia during transportation, active warming before induction of anaesthesia, active warming during anaesthesia and surgery, and accurate measurement of core temperature. Perioperative temperature management must also prevent hyperthermia in children.
Collapse
|
6
|
Kundrick E, Marrero-Rosado B, Stone M, Schultz C, Walker K, Lee-Stubbs RB, de Araujo Furtado M, Lumley LA. Delayed midazolam dose effects against soman in male and female plasma carboxylesterase knockout mice. Ann N Y Acad Sci 2020; 1479:94-107. [PMID: 32027397 DOI: 10.1111/nyas.14311] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/13/2020] [Accepted: 01/19/2020] [Indexed: 01/30/2023]
Abstract
Chemical warfare nerve agent exposure leads to status epilepticus that may progress to epileptogenesis and severe brain pathology when benzodiazepine treatment is delayed. We evaluated the dose-response effects of delayed midazolam (MDZ) on toxicity induced by soman (GD) in the plasma carboxylesterase knockout (Es1-/- ) mouse, which, similar to humans, lacks plasma carboxylesterase. Initially, we compared the median lethal dose (LD50 ) of GD exposure in female Es1-/- mice across estrous with male mice and observed a greater LD50 during estrus compared with proestrus or with males. Subsequently, male and female GD-exposed Es1-/- mice treated with a dose range of MDZ 40 min after seizure onset were evaluated for survivability, seizure activity, and epileptogenesis. GD-induced neuronal loss and microglial activation were evaluated 2 weeks after exposure. Similar to our previous observations in rats, delayed treatment with MDZ dose-dependently increased survival and reduced seizure severity in GD-exposed mice, but was unable to prevent epileptogenesis, neuronal loss, or gliosis. These results suggest that MDZ is beneficial against GD exposure, even when treatment is delayed, but that adjunct therapies to enhance protection need to be identified. The Es1-/- mouse GD exposure model may be useful to screen for improved medical countermeasures against nerve agent exposure.
Collapse
Affiliation(s)
- Erica Kundrick
- US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland
| | - Brenda Marrero-Rosado
- US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland
| | - Michael Stone
- US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland
| | - Caroline Schultz
- US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland
| | - Katie Walker
- US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland
| | - Robyn B Lee-Stubbs
- US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland
| | | | - Lucille A Lumley
- US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland
| |
Collapse
|
7
|
Prophylactic vs. therapeutic magnesium sulfate for shivering during spinal anesthesia. EGYPTIAN JOURNAL OF ANAESTHESIA 2019. [DOI: 10.1016/j.egja.2013.07.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
8
|
Bräuer A, Müller MM, Wetz AJ, Quintel M, Brandes IF. Influence of oral premedication and prewarming on core temperature of cardiac surgical patients: a prospective, randomized, controlled trial. BMC Anesthesiol 2019; 19:55. [PMID: 30987594 PMCID: PMC6466686 DOI: 10.1186/s12871-019-0725-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 04/02/2019] [Indexed: 12/21/2022] Open
Abstract
Background Perioperative hypothermia is still very common and associated with numerous adverse effects. The effects of benzodiazepines, administered as premedication, on thermoregulation have been studied with conflicting results. We investigated the hypotheses that premedication with flunitrazepam would lower the preoperative core temperature and that prewarming could attenuate this effect. Methods After approval by the local research ethics committee 50 adult cardiac surgical patients were included in this prospective, randomized, controlled, single-centre study with two parallel groups in a university hospital setting. Core temperature was measured using a continuous, non-invasive zero-heat flux thermometer from 30 min before administration of the oral premedication until beginning of surgery. An equal number of patients was randomly allocated via a computer-generated list assigning them to either prewarming or control group using the sealed envelope method for blinding. The intervention itself could not be blinded. In the prewarming group patients received active prewarming using an underbody forced-air warming blanket. The data were analysed using Student’s t-test, Mann-Whitney U-test and Fisher’s exact test. Results Of the randomized 25 patients per group 24 patients per group could be analysed. Initial core temperature was 36.7 ± 0.2 °C and dropped significantly after oral premedication to 36.5 ± 0.3 °C when the patients were leaving the ward and to 36.4 ± 0.3 °C before induction of anaesthesia. The patients of the prewarming group had a significantly higher core temperature at the beginning of surgery (35.8 ± 0.4 °C vs. 35.5 ± 0.5 °C, p = 0.027), although core temperature at induction of anaesthesia was comparable. Despite prewarming, core temperature did not reach baseline level prior to premedication (36.7 ± 0.2 °C). Conclusions Oral premedication with benzodiazepines on the ward lowered core temperature significantly at arrival in the operating room. This drop in core temperature cannot be offset by a short period of active prewarming. Trial registration This trial was prospectively registered with the German registry of clinical trials under the trial number DRKS00005790 on 20th February 2014.
Collapse
Affiliation(s)
- Anselm Bräuer
- Department of Anaesthesiology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075, Göttingen, Germany
| | - Michaela Maria Müller
- Department of Anaesthesiology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075, Göttingen, Germany
| | - Anna Julienne Wetz
- Department of Anaesthesiology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075, Göttingen, Germany
| | - Michael Quintel
- Department of Anaesthesiology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075, Göttingen, Germany
| | - Ivo Florian Brandes
- Department of Anaesthesiology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075, Göttingen, Germany.
| |
Collapse
|
9
|
Conway A, Ersotelos S, Sutherland J, Duff J. Forced air warming during sedation in the cardiac catheterisation laboratory: a randomised controlled trial. Heart 2017; 104:685-690. [PMID: 28988209 PMCID: PMC5890638 DOI: 10.1136/heartjnl-2017-312191] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 09/19/2017] [Accepted: 09/21/2017] [Indexed: 01/25/2023] Open
Abstract
OBJECTIVE Forced air warming (FAW) during general anaesthesia is a safe and effective intervention used to reduce hypothermia. The objective of this study was to determine if FAW reduces hypothermia when used for procedures performed with sedation in the cardiac catheterisation laboratory. METHODS A parallel-group randomised controlled trial was conducted. Adults receiving sedation in a cardiac catheterisation laboratory at two sites were randomised to receive FAW or usual care, which involved passive warming with heated cotton blankets. Hypothermia, defined as a temperature less than 36°C measured with a sublingual digital thermometer after procedures, was the primary outcome. Other outcomes were postprocedure temperature, shivering, thermal comfort and major complications. RESULTS A total of 140 participants were randomised. Fewer participants who received FAW were hypothermic (39/70, 56% vs 48/69, 70%, difference 14%; adjusted RR 0.75, 95% CI=0.60 to 0.94), and body temperature was 0.3°C higher (95% CI=0.1 to 0.5, p=0.004). FAW increased thermal comfort (63/70, 90% vs51/69, 74% difference 16%, RR 1.21, 95% CI=1.04 to 1.42). The incidence of shivering was similar (3/69, 4% vs 0/71 0%, difference 4%, 95% CI=-1.1 to 9.8). One patient in the control group required reintervention for bleeding. No other major complications occurred. CONCLUSION FAW reduced hypothermia and improved thermal comfort. The difference in temperature between groups was modest and less than that observed in previous studies where use of FAW decreased risk of surgical complications. Therefore, it should not be considered clinically significant. TRIAL REGISTRATION NUMBER ACTRN12616000013460.
Collapse
Affiliation(s)
- Aaron Conway
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia.,Cardiac Catheter Theatres, The Wesley Hospital, Brisbane, Queensland, Australia
| | - Suzanna Ersotelos
- Cardiac Catheter Laboratory, St Vincent's Private Hospital, Sydney, Australia
| | - Joanna Sutherland
- Department of Anaesthesia, Coffs Harbour Health Campus, Coffs Harbour, Australia.,Rural Clinical School, University of New South Wales, Coffs Harbour, New South Wales, Australia
| | - Jed Duff
- School of Nursing and Midwifery, University of Newcastle, Callaghan, New South Wales, Australia
| |
Collapse
|
10
|
MAGNESIUM SULPHATE INFUSION PREVENTS SHIVERING DURING SPINAL ANAESTHESIA: A RANDOMISED DOUBLE BLINDED CONTROLLED STUDY. ACTA ACUST UNITED AC 2016. [DOI: 10.14260/jemds/2016/1052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
|
11
|
Conway A. A Review of the Effects of Sedation on Thermoregulation: Insights for the Cardiac Catheterization Laboratory. J Perianesth Nurs 2016; 31:226-36. [DOI: 10.1016/j.jopan.2014.07.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 04/10/2014] [Accepted: 07/31/2014] [Indexed: 12/21/2022]
|
12
|
Safavi M, Honarmand A, Mohammadsadeqie S. Prophylactic use of intravenous ondansetron versus ketamine - midazolam combination for prevention of shivering during spinal anesthesia: A randomized double-blind placebo-controlled trial. Adv Biomed Res 2015; 4:207. [PMID: 26605236 PMCID: PMC4627177 DOI: 10.4103/2277-9175.166143] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 05/19/2015] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND The aim of this study was to compare the efficacy intravenous (IV) ondansetron with ketamine plus midazolam for the prevention of shivering during spinal anesthesia (SA). MATERIALS AND METHODS Ninety patients, aged 18-65 years, undergoing lower extremity orthopedic surgery were included in the present study. SA was performed in all patients with hyperbaric bupivacaine 15 mg. The patients were randomly allocated to receive normal saline (Group C), ondansetron 8 mg IV (Group O) or ketamine 0.25 mg/kg IV plus midazolam 37.5 μg/kg IV (Group KM) immediately after SA. During surgery, shivering scores were recorded at 5 min intervals. The operating room temperature was maintained at 24°C. RESULTS The incidences of shivering were 18 (60%) in Group C, 6 (20%) in Group KM and 8 (26.6%) in Group O. The difference between Groups O and Group KM with Group C was statistically significant (P < 0.05). No significant difference was noted between Groups KM with Group O in this regard (P > 0.05). Peripheral and core temperature changes throughout surgery were not significantly different among three groups (P > 0.05). Incidence (%) of hallucination was not significantly different between the three groups (0, 3.3, 0 in Group O, Group KM, Group C respectively, P > 0.05). CONCLUSION Prophylactic use of ondansetron 8 mg IV was comparable to ketamine 0.25 mg/kg IV plus midazolam 37.5 μg/kg IV in preventing shivering during SA.
Collapse
Affiliation(s)
- Mohammadreza Safavi
- Anesthesiology and Critical Care Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Azim Honarmand
- Anesthesiology and Critical Care Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Sara Mohammadsadeqie
- Anesthesiology and Critical Care Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| |
Collapse
|
13
|
Conway A, Kennedy W, Sutherland J. Inadvertent Hypothermia After Procedural Sedation and Analgesia in a Cardiac Catheterization Laboratory: A Prospective Observational Study. J Cardiothorac Vasc Anesth 2015; 29:1285-90. [PMID: 26384630 DOI: 10.1053/j.jvca.2015.06.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Indexed: 02/08/2023]
Abstract
OBJECTIVES To identify the prevalence of and risk factors for inadvertent hypothermia after procedures performed with procedural sedation and analgesia in a cardiac catheterization laboratory. DESIGN A single-center, prospective observational study. SETTING A tertiary-care private hospital in Australia. PARTICIPANTS 399 patients undergoing elective procedures with procedural sedation and analgesia were included. Propofol infusions were used when an anesthesiologist was present. Otherwise, bolus doses of either midazolam or fentanyl or a combination of these medications was used. INTERVENTIONS None MEASUREMENTS AND MAIN RESULTS Hypothermia was defined as a temperature<36.0°C. Multivariate logistic regression was used to identify risk factors. Hypothermia was present after 23.3% (n = 93; 95% confidence interval [CI] 19.2%-27.4%) of 399 procedures. Sedative regimens with the highest prevalence of hypothermia were any regimen that included propofol (n = 35; 40.2%; 95% CI 29.9%-50.5%) and the use of fentanyl combined with midazolam (n = 23; 20.3%; 95% CI 12.9%-27.7%). Difference in mean temperature from pre-procedure to post-procedure was -0.27°C (standard deviation 0.45). Receiving propofol (odds ratio [OR] 4.6 95% CI 2.5-8.6), percutaneous coronary intervention (OR 3.2; 95% CI 1.7-5.9), body mass index<25 (OR 2.5; 95% CI 1.4-4.4) and being hypothermic prior to the procedure (OR 4.9; 95% CI 2.3-10.8) were independent predictors of post-procedural hypothermia. CONCLUSIONS A moderate prevalence of hypothermia was observed. The small absolute change in temperature observed may not be a clinically important amount. More research is needed to increase confidence in the authors' estimates of hypothermia in sedated patients and its impact on clinical outcomes.
Collapse
Affiliation(s)
- Aaron Conway
- Institute of Health and Biomedical Innovation, Queensland University Technology, Kelvin Grove, QLD, Australia.
| | - Wendy Kennedy
- Cardiac Catheter Laboratories, Princess Alexandra Hospital, Wooloongabba, QLD, Australia
| | - Joanna Sutherland
- Coffs Harbour Health Campus and Rural Clinical School, Coffs Harbour, NSW, Australia
| |
Collapse
|
14
|
Abstract
Prewarming is a useful and effective measure to reduce perioperative hypothermia. Due to §23(3) of the German Infektionsschutzgesetz (Gesetz zur Verhütung und Bekämpfung von Infektionskrankheiten beim Menschen, Infection Act, act on protection and prevention of infectious diseases in man) and the recommendations of the Hospital Hygiene and Infection Prevention Committee of the Robert Koch Institute, implementation of prewarming is clearly recommended. There are several technically satisfactory and practicable devices available allowing prewarming on the normal hospital ward, in the preoperative holding area or in the induction room of the operating theater (OR) The implementation of prewarming requires additional equipment and training of staff. Using a locally adapted concept for the implementation of prewarming does not lead to inefficiency in the perioperative process. In contrast, the implementation can help to achieve stable arrival times for patients in the OR.
Collapse
|
15
|
Gozdemir M, Usta B, Demircioglu RI, Muslu B, Sert H, Karatas OF. Magnesium sulfate infusion prevents shivering during transurethral prostatectomy with spinal anesthesia: a randomized, double-blinded, controlled study. J Clin Anesth 2011; 22:184-9. [PMID: 20400004 DOI: 10.1016/j.jclinane.2009.06.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2008] [Revised: 06/03/2009] [Accepted: 06/22/2009] [Indexed: 11/17/2022]
Abstract
STUDY OBJECTIVE To determine whether magnesium sulfate (MgSO(4)) infusion during surgery reduces shivering during spinal anesthesia. DESIGN Double-blinded placebo-controlled, randomized trial. SETTING Operation room of a university hospital. PATIENTS 60 patients, aged 40 to 70 years, scheduled for elective transurethral resection of the prostate (TURP) during spinal anesthesia. INTERVENTIONS Subarachnoid anesthesia consisting of hyperbaric bupivacaine three mL 0.5% was injected using a 25-G Quincke spinal needle. Patients received either saline (Group C, n = 30) or MgSO(4) (Group Mg, n = 30). Group Mg received an intravenous (IV) bolus of MgSO(4) 80 mg/kg via syringe pump over a 30-minute period, followed by a two g/hr infusion during the intraoperative period. Group C received an equal volume of saline. MEASUREMENTS Motor blockade was evaluated by Bromage motor scale. Sensory block level was assessed by pinprick test. Shivering was assessed after the completion of subarachnoid drug injection. Side effects were recorded. MAIN RESULTS Hypothermia was observed in all patients (100%) in Group Mg and in 24 patients (80%) in Group C (P = 0.024). The decrease in core temperature in Group Mg was significantly greater (P < 0.005). Shivering was observed in two patients (6.7%) in Group Mg and 20 patients (66.7%) in Group C (P = 0.0001). CONCLUSIONS MgSO(4) infusion in the perioperative period significantly reduced shivering during TURP with spinal anesthesia. MgSO(4) infusion prevents shivering in patients receiving spinal anesthesia but increases the risk of hypothermia.
Collapse
Affiliation(s)
- Muhammet Gozdemir
- Department of Anesthesiology and Reanimation, Fatih University School of Medicine, Ankara 06540, Turkey.
| | | | | | | | | | | |
Collapse
|
16
|
Masamune T, Sato H, Okuyama K, Imai Y, Iwashita H, Ishiyama T, Oguchi T, Sessler DI, Matsukawa T. The Shivering Threshold in Rabbits with JM-1232(−), a New Benzodiazepine Receptor Agonist. Anesth Analg 2009; 109:96-100. [DOI: 10.1213/ane.0b013e3181a1a5ed] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
17
|
Forced-air warming effectively prevents midazolam-induced core hypothermia in volunteers. Eur J Anaesthesiol 2009; 26:566-71. [DOI: 10.1097/eja.0b013e328328f662] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
18
|
Therapeutic hypothermia and controlled normothermia in the intensive care unit: practical considerations, side effects, and cooling methods. Crit Care Med 2009; 37:1101-20. [PMID: 19237924 DOI: 10.1097/ccm.0b013e3181962ad5] [Citation(s) in RCA: 466] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Hypothermia is being used with increasing frequency to prevent or mitigate various types of neurologic injury. In addition, symptomatic fever control is becoming an increasingly accepted goal of therapy in patients with neurocritical illness. However, effectively controlling fever and inducing hypothermia poses special challenges to the intensive care unit team and others involved in the care of critically ill patients. OBJECTIVE To discuss practical aspects and pitfalls of therapeutic temperature management in critically ill patients, and to review the currently available cooling methods. DESIGN Review article. INTERVENTIONS None. MAIN RESULTS Cooling can be divided into three distinct phases: induction, maintenance, and rewarming. Each has its own risks and management problems. A number of cooling devices that have reached the market in recent years enable reliable maintenance and slow and controlled rewarming. In the induction phase, rapid cooling rates can be achieved by combining cold fluid infusion (1500-3000 mL 4 degrees C saline or Ringer's lactate) with an invasive or surface cooling device. Rapid induction decreases the risks and consequences of short-term side effects, such as shivering and metabolic disorders. Cardiovascular effects include bradycardia and a rise in blood pressure. Hypothermia's effect on myocardial contractility is variable (depending on heart rate and filling pressure); in most patients myocardial contractility will increase, although mild diastolic dysfunction can develop in some patients. A risk of clinically significant arrhythmias occurs only if core temperature decreases below 30 degrees C. The most important long-term side effects of hypothermia are infections (usually of the respiratory tract or wounds) and bedsores. CONCLUSIONS Temperature management and hypothermia induction are gaining importance in critical care medicine. Intensive care unit physicians, critical care nurses, and others (emergency physicians, neurologists, and cardiologists) should be familiar with the physiologic effects, current indications, techniques, complications and practical issues of temperature management, and induced hypothermia. In experienced hands the technique is safe and highly effective.
Collapse
|
19
|
Machata AM, Willschke H, Kabon B, Prayer D, Marhofer P. Effect of brain magnetic resonance imaging on body core temperature in sedated infants and children. Br J Anaesth 2009; 102:385-9. [PMID: 19174372 DOI: 10.1093/bja/aen388] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Children undergoing magnetic resonance imaging (MRI) under sedation are at risk of hypo- or hyperthermia. The effect of brain MRI at differing magnetic field strengths on body core temperature in sedated infants and young children has not been reported previously. METHODS Two groups of 38 infants and children (aged 1 month to 6 yr 5 months) underwent brain MRI for different indications related to cerebral diseases, at 1.5 Tesla (T) and 3 T MRI units, respectively. All patients received deep sedation comprising midazolam, nalbuphine, and propofol. Pre-scan and post-scan temperatures were measured at the right tympanic and at rectal sites. No active warming devices were used during the procedures. RESULTS Body core temperature measurements were similar between right tympanic and rectal site before and after the scans. After 1.5 T scans, the median (IQR) increase from pre-scan to post-scan tympanic temperature was 0.2 degrees C (0.1-0.3), and the median (IQR) rectal temperature increase was 0.2 degrees C (0-0.3) (P<0.001). After 3 T scans, the median (IQR) tympanic temperature increase was 0.5 degrees C (0.4-0.7), and the median (IQR) rectal temperature increase was 0.5 degrees C (0.3-0.6) (P<0.001). CONCLUSIONS Body core temperature increased significantly during 1.5 and 3 T examinations; this increase was more profound during 3 T MRI. Patient heating occurred despite minimal efforts to reduce passive heat loss under sedation and without the use of warming devices.
Collapse
Affiliation(s)
- A-M Machata
- Department of Anaesthesia, General Intensive Care and Pain Therapy, Medical University of Vienna, General Hospital, Waehringer Guertel 18-20, A-1090 Vienna, Austria.
| | | | | | | | | |
Collapse
|
20
|
Munerato MS, Zanetti EDS, Marques JA, Duarte JMB. Effects of laparoscopy on the cardiorespiratory system of brown brocket deer (Mazama gouazoubira) anesthetized with ketamine/ xylazine/ midazolam combination and isoflurane. PESQUISA VETERINARIA BRASILEIRA 2008. [DOI: 10.1590/s0100-736x2008001100003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Laparoscopy is not widely used as a tool to perform assisted reproduction techniques in South American cervids; thus, scarce information in literature is available regarding its effects and appropriate anesthetic protocols to perform it. This study evaluated the effect of laparoscopy on heart rate (HR), respiration rate (RR), saturation of oxyhemoglobin (SpO2) and rectal temperature (RT) of six female brown brocket deer (Mazama gouazoubira) anesthetized with ketamine (5mg/kg), xylazine (0.3mg/kg), midazolam (0.5mg/kg) combination i.v. and isoflurane. Twelve laparoscopies were performed and each animal was used twice with a 40-day interval. After anesthetized, the animals were placed in dorsal recumbency to perform laparoscopy procedure using abdominal CO2 insufflations (14.2 ± 2.39mmHg; M ± SE). The main events of the laparoscopy procedure were divided into three periods: animal without (P1) and with abdominal insufflation (P2) and abdominal insufflation with the hips raised at 45º (P3). As a control, the animals were anesthetized again 40 days after the last laparoscopy, and were maintained in a dorsal recumbency for the same average duration of the previous anesthesia and no laparoscopy procedure was conducted. The period of anesthesia for the controls was also divided into P1, P2, and P3 considering the average duration of these periods in previous laparoscopies performed. Data were analyzed through the (ANOVA) variance analysis followed by Tukey test and values at P<0.05 were considered significant. No significant differences were observed in the parameters evaluated at P1, P2 and P3 between the animals submitted to laparoscopy and control. However, the RR mean between P1 (38.8 ± 4.42) and P3 (32.7 ± 4.81); and the RT mean between the P1 (38.2ºC ± 0.17), P2 (37.6ºC ± 0.19) and P3 (37.0ºC ± 0.21) varied significantly, independent of the laparoscopy. These data indicated that laparoscopy didn't cause any significant alterations in the cardiorespiratory parameters evaluated, even though the anesthetic protocol used can cause a reduction in the RT contributing to development of hypothermia during anesthesia.
Collapse
|
21
|
Abstract
Most clinically available thermometers accurately report the temperature of whatever tissue is being measured. The difficulty is that no reliably core-temperature-measuring sites are completely noninvasive and easy to use-especially in patients not undergoing general anesthesia. Nonetheless, temperature can be reliably measured in most patients. Body temperature should be measured in patients undergoing general anesthesia exceeding 30 min in duration and in patients undergoing major operations during neuraxial anesthesia. Core body temperature is normally tightly regulated. All general anesthetics produce a profound dose-dependent reduction in the core temperature, triggering cold defenses, including arteriovenous shunt vasoconstriction and shivering. Anesthetic-induced impairment of normal thermoregulatory control, with the resulting core-to-peripheral redistribution of body heat, is the primary cause of hypothermia in most patients. Neuraxial anesthesia also impairs thermoregulatory control, although to a lesser extent than does general anesthesia. Prolonged epidural analgesia is associated with hyperthermia whose cause remains unknown.
Collapse
Affiliation(s)
- Daniel I Sessler
- Department of Outcomes Research, The Cleveland Clinic-P77, Cleveland, Ohio 44195, USA.
| |
Collapse
|
22
|
Kim HJ, Jeon GE, Choi JM, Jeong SM, Seong KW, Yang HS. The Effects of Temperature Monitoring Methods and Thermal Management Methods during Spinal Surgery. Korean J Anesthesiol 2008. [DOI: 10.4097/kjae.2008.54.6.623] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Hye Jin Kim
- Department of Anesthesiology and Pain Medicine, Gangneung Asan Hospital, Gangneung, Korea
| | - Go Eun Jeon
- Department of Anesthesiology and Pain Medicine, Gangneung Asan Hospital, Gangneung, Korea
| | - Jae Moon Choi
- Department of Anesthesiology and Pain Medicine, Gangneung Asan Hospital, Gangneung, Korea
| | - Sung Moon Jeong
- Department of Anesthesiology and Pain Medicine, Gangneung Asan Hospital, Gangneung, Korea
| | - Kyu Wan Seong
- Department of Anesthesiology and Pain Medicine, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea
| | - Hong Seuk Yang
- Department of Anesthesiology and Pain Medicine, Gangneung Asan Hospital, Gangneung, Korea
| |
Collapse
|
23
|
Severens NMW, van Marken Lichtenbelt WD, Frijns AJH, Van Steenhoven AA, de Mol BAJM, Sessler DI. A model to predict patient temperature during cardiac surgery. Phys Med Biol 2007; 52:5131-45. [PMID: 17762076 DOI: 10.1088/0031-9155/52/17/002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A core temperature drop after cardiac surgery slows down the patient's recuperation process. In order to minimize the amount of the so-called afterdrop, more knowledge is needed about the impaired thermoregulatory system during anesthesia and the effect of different protocols on temperature distribution. Therefore, a computer model has been developed that describes heat transfer during cardiac surgery. The model consists of three parts: (1) a passive part, which gives a simplified description of the human geometry and the passive heat transfer processes, (2) an active part that takes into account the thermoregulatory system as a function of the amount of anesthesia and (3) submodels, through which it is possible to adjust the boundary conditions. The validity of the new model was tested by comparing the model results to the measurement results of three surgical procedures. A good resemblance was found between simulation results and the experiments. Next, a model application was shown. A parameter study was performed to study the effect of different temperature protocols on afterdrop. It was shown that the effectiveness of forced-air heating is larger than the benefits resulting from increased environmental temperature or usage of a circulating water mattress. Ultimately, the model could be used to develop a monitoring decision system that advises clinicians what temperature protocol will be best for the patient.
Collapse
Affiliation(s)
- N M W Severens
- Department of Mechanical Engineering, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands.
| | | | | | | | | | | |
Collapse
|
24
|
Abstract
Perioperative hypothermia can influence clinical outcome negatively. It triples the incidence of adverse myocardial outcomes, significantly increases perioperative blood loss, significantly augments allogenic transfusion requirements, and increases the incidence of surgical wound infections. The major causes are redistribution of heat from the core of the body to the peripheral tissues and a negative heat balance. Adequate thermal management includes preoperative and intraoperative measures. Preoperative measures, e.g., prewarming, enhance heat content of the peripheral tissues, thereby reducing redistribution of heat from the core to the peripheral tissues after induction of anesthesia. Intraoperative measures are active skin surface warming of a large body surface area with conductive or convective warming systems. Intravenous fluids should be warmed when large volumes of more than 500-1000 ml/h are required. The body surfaces that cannot be actively warmed should be insulated. Airway humidification and conductive warming of the back are less efficient.
Collapse
Affiliation(s)
- A Bräuer
- Zentrum Anaesthesiologie, Rettungs- und Intensivmedizin, Georg-August-Universität, Robert-Koch-Strasse 40, 37075 Göttingen.
| | | | | |
Collapse
|
25
|
Grint NJ, Murison PJ. Peri-operative body temperatures in isoflurane-anaesthetized rabbits following ketamine-midazolam or ketamine-medetomidine. Vet Anaesth Analg 2007; 34:181-9. [PMID: 17444931 DOI: 10.1111/j.1467-2995.2006.00319.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To investigate alterations in peri-operative body temperatures and oesophageal-skin temperatures in isoflurane-anaesthetized rabbits following either ketamine-midazolam or ketamine-medetomidine induction of anaesthesia. ANIMAL POPULATION Fifty client-owned rabbits, (25 male, 25 female) of different breeds anaesthetized for elective neutering (age range: 3-42 months; mass range: 1.15-4.3 kg). STUDY DESIGN Randomized, blinded clinical study. METHODS Pre-anaesthetic rectal temperature was measured. A 24 SWG catheter was placed in a marginal ear vein after local anaesthesia. Ketamine (15 mg kg(-1)) with medetomidine (0.25 mg kg(-1)) (group KMT) or with midazolam (3 mg kg(-1)) (group KMZ) was injected intramuscularly (IM). Following endotracheal intubation anaesthesia was maintained with isoflurane in oxygen. Carprofen (3 mg kg(-1)) and glucose saline (5 mL kg(-1) hour(-1)) were administered through the intravenous catheter. Room temperature and humidity, skin temperature (from tip of pinna) and oesophageal temperature were measured during anaesthesia. Ovariohysterectomy or castration was performed. Rectal temperature was taken when isoflurane was discontinued (time zero) and 30, 60 and 120 minutes thereafter. Atipamezole (0.5 mg kg(-1)) was administered IM to rabbits in group KMT at zero plus 30 minutes. Mass, averaged room temperature and duration of anaesthesia data were compared using a two-tailed t-test. Age, averaged room humidity, rectal temperature decrease, oesophageal temperature decrease and oesophageal-skin difference data were compared using a Kruskal-Wallis test. p < 0.05 was considered significant. RESULTS The averaged oesophageal-skin temperature difference was significantly greater in group KMT [median 9.85 degrees C (range 6.42-13.85 degrees C)] than in group KMZ [4.38 degrees C (2.83-10.43 degrees C)]. Rectal temperature decreased over the anaesthetic period was not significantly different between the two groups; however, oesophageal temperature decrease was significantly less in group KMT [1.1 degrees C (-0.1-+2.7 degrees C)] than in group KMZ [1.4 degrees C (0.6-3.1 degrees C)]. CONCLUSIONS Oesophageal-skin temperature difference is larger in rabbits anaesthetized with ketamine-medetomidine combination than ketamine-midazolam. CLINICAL RELEVANCE The oesophageal temperature in rabbits anaesthetized with ketamine-medetomidine and isoflurane decreases significantly less than in animals anaesthetized with ketamine-midazolam and isoflurane, during anaesthesia.
Collapse
Affiliation(s)
- Nicola J Grint
- Department of Clinical Veterinary Science, University of Bristol, Bristol, UK.
| | | |
Collapse
|
26
|
D'Angelo Vanni SM, Castiglia YMM, Ganem EM, Rodrigues Júnior GR, Amorim RB, Ferrari F, Braz LG, Braz JRC. Preoperative warming combined with intraoperative skin-surface warming does not avoid hypothermia caused by spinal anesthesia in patients with midazolam premedication. SAO PAULO MED J 2007; 125:144-9. [PMID: 17923938 PMCID: PMC11020579 DOI: 10.1590/s1516-31802007000300004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Revised: 12/01/2005] [Accepted: 05/24/2007] [Indexed: 11/22/2022] Open
Abstract
CONTEXT AND OBJECTIVE Inadvertent perioperative hypothermia is common during spinal anesthesia and after midazolam administration. The aim of this study was to evaluate the effects of intraoperative skin-surface warming with and without 45 minutes of preoperative warming in preventing intraoperative and postoperative hypothermia caused by spinal anesthesia in patients with midazolam premedication. DESIGN AND SETTING Prospective and randomized study at Hospital das Clínicas, Universidade Estadual Paulista, Botucatu. METHODS Thirty patients presenting American Society of Anesthesiologists (ASA) physical status I and II who were scheduled for elective lower abdominal surgery were utilized. The patients received midazolam premedication (7.5 mg by intramuscular injection) and standard spinal anesthesia. Ten patients (Gcontrol) received preoperative and intraoperative passive thermal insulation. Ten patients (Gpre+intra) underwent preoperative and intraoperative active warming. Ten patients (Gintra) were only warmed intraoperatively. RESULTS After 45 min of preoperative warming, the patients in Gpre+intra had significantly higher core temperatures than did the patients in the unwarmed groups (Gcontrol and Gintra) before the anesthesia (p < 0.05) but not at the beginning of surgery (p > 0.05). The patients who were warmed intraoperatively had significantly higher core temperatures than did the patients in Gcontrol at the end of surgery (p < 0.05). All the patients were hypothermic at admission to the recovery room (T CORE < 36 degrees C). CONCLUSIONS Forty-five minutes of preoperative warming combined with intraoperative skin-surface warming does not avoid but minimizes hypothermia caused by spinal anesthesia in patients with midazolam premedication.
Collapse
Affiliation(s)
- Simone Maria D'Angelo Vanni
- Department of Anesthesiology, School of Medicine, Universidade Estadual Paulista, Botucatu, São Paulo, Brazil
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Abstract
Experimental evidence and clinical experience suggest that mild hypothermia protects numerous tissues from damage during ischemic insult. However, the extent to which hypothermia becomes a valued therapeutic option will depend on the clinician's ability to rapidly reduce core body temperature and safely maintain hypothermia. To date, general anesthesia is the best way to block autonomic defenses during induction of mild-to-moderate hypothermia; unfortunately, general anesthesia is not an option in most patients likely to benefit from therapeutic hypothermia. Induction of hypothermia in awake humans is complicated by both the technical difficulties related to thermal manipulation and the remarkable efficacy of thermoregulatory defenses, especially vasoconstriction and shivering. The most effective thermal manipulation devices are generally invasive and, therefore, more prone to complications than surface methods. In an effort to inhibit thermoregulation in awake humans, several agents have been tested either alone or in combination with each other. For example, the combination of meperidine and buspirone has already been applied to facilitate induction of hypothermia in human trials. However, pharmacological induction of thermoregulatory tolerance to cold without excessive sedation, respiratory depression, or other serious toxicity remains a major focus of current therapeutic hypothermia research.
Collapse
Affiliation(s)
- Anthony G Doufas
- Outcomes Research Institute, Department of Anesthesiology and Perioperative Medicine, University of Louisville, Louisville, KY, USA.
| | | |
Collapse
|
28
|
Wadhwa A, Sengupta P, Durrani J, Akça O, Lenhardt R, Sessler DI, Doufas AG. Magnesium sulphate only slightly reduces the shivering threshold in humans. Br J Anaesth 2005; 94:756-62. [PMID: 15749735 PMCID: PMC1361806 DOI: 10.1093/bja/aei105] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Hypothermia may be an effective treatment for stroke or acute myocardial infarction; however, it provokes vigorous shivering, which causes potentially dangerous haemodynamic responses and prevents further hypothermia. Magnesium is an attractive anti-shivering agent because it is used for treatment of postoperative shivering and provides protection against ischaemic injury in animal models. We tested the hypothesis that magnesium reduces the threshold (triggering core temperature) and gain of shivering without substantial sedation or muscle weakness. METHODS We studied nine healthy male volunteers (18-40 yr) on two randomly assigned treatment days: (1) control and (2) magnesium (80 mg kg(-1) followed by infusion at 2 g h(-1)). Lactated Ringer's solution (4 degrees C) was infused via a central venous catheter over a period of approximately 2 h to decrease tympanic membrane temperature by approximately 1.5 degrees C h(-1). A significant and persistent increase in oxygen consumption identified the threshold. The gain of shivering was determined by the slope of oxygen consumption vs core temperature regression. Sedation was evaluated using a verbal rating score (VRS) from 0 to 10 and bispectral index (BIS) of the EEG. Peripheral muscle strength was evaluated using dynamometry and spirometry. Data were analysed using repeated measures anova; P<0.05 was statistically significant. RESULTS Magnesium reduced the shivering threshold (36.3 [SD 0.4] degrees C vs 36.6 [0.3] degrees C, P = 0.040). It did not affect the gain of shivering (control, 437 [289] ml min(-1) degrees C(-1); magnesium, 573 [370] ml min(-1) degrees C(-1); P=0.344). The magnesium bolus did not produce significant sedation or appreciably reduce muscle strength. CONCLUSIONS Magnesium significantly reduced the shivering threshold. However, in view of the modest absolute reduction, this finding is considered to be clinically unimportant for induction of therapeutic hypothermia.
Collapse
Affiliation(s)
- Anupama Wadhwa
- Assistant Professor, OUTCOMES RESEARCH™ Institute and Department of Anesthesiology and Perioperative Medicine, University of Louisville
| | - Papiya Sengupta
- Research Fellow, OUTCOMES RESEARCH™ Institute, University of Louisville
| | - Jaleel Durrani
- Resident, Department of Anesthesiology and Perioperative Medicine, University of Louisville
| | - Ozan Akça
- Assistant Director OUTCOMES RESEARCH™ Institute, Assistant Professor Department of Anesthesiology and Perioperative Medicine, Director Neurosciences Intensive Care Unit, University of Louisville
| | - Rainer Lenhardt
- Assistant Director OUTCOMES RESEARCH™ Institute, Assistant Professor Department of Anesthesiology and Perioperative Medicine, Director Neurosciences Intensive Care Unit, University of Louisville
| | - Daniel I. Sessler
- Vice Dean for Research, Associate Vice President for Health Affairs, Director OUTCOMES RESEARCH™ Institute, Lolita & Samuel Weakley Distinguished University Research Chair, Professor of Anesthesiology and Pharmacology, University of Louisville
| | - Anthony G. Doufas
- Assistant Professor and Director of Research, Department of Anesthesiology and Perioperative Medicine and OUTCOMES RESEARCH™ Institute, University of Louisville
| |
Collapse
|
29
|
Echizenya M, Mishima K, Satoh K, Kusanagi H, Sekine A, Ohkubo T, Shimizu T, Hishikawa Y. Enhanced heat loss and age-related hypersensitivity to diazepam. J Clin Psychopharmacol 2004; 24:639-46. [PMID: 15538127 DOI: 10.1097/01.jcp.0000144890.45234.e9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Whether elderly people suffer from age-related changes in pharmacokinetics and/or pharmacodynamics with administration of benzodiazepines is still a matter of controversy. We investigated the course of brain function and thermoregulation after oral administration of a standard benzodiazepine, diazepam (DZP), in 8 healthy young men (mean age, 19.8 years; range, 18 to 23 years) and 8 healthy middle-aged and older men (mean age, 60.9 years; range, 53 to 71 years). Placebo or DZP was administered in a single-blind crossover manner to the young men (placebo, 5-mg, 10-mg DZP) and to the older men (placebo, 5-mg DZP), and plasma DZP concentration, choice reaction time, proximal body temperature, and distal body temperature were monitored with high time resolution under a modified constant routine condition to exclude masking effects. Whereas there was no evidence of age-related alterations in pharmacokinetics between the 2 groups, the older subjects, in comparison to the young subjects, showed a more delayed choice reaction time in response to the same plasma DZP level, suggesting that hypersensitivity is related to increased age. DZP at 5 mg in the older subjects induced acute and transient hypothermia to the same degree as that induced by DZP at 10 mg in the young subjects. The distal-proximal body temperature gradient (difference between distal body temperature and proximal body temperature), an indicator of blood flow in distal skin regions, showed strong positive correlation with the delay in choice reaction time in both groups. These findings suggest that hypersensitivity to benzodiazepine in older persons may be due, at least in part, to age-related changes in thermoregulation, especially in the heat loss process.
Collapse
Affiliation(s)
- Masaru Echizenya
- Division of Neuropsychiatry, Department of Neuro and Locomotor Science, Akita University School of Medicine, Akita, Japan
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Toyota K, Sakura S, Saito Y, Ozasa H, Uchida H. The effect of pre-operative administration of midazolam on the development of intra-operative hypothermia. Anaesthesia 2004; 59:116-21. [PMID: 14725512 DOI: 10.1111/j.1365-2044.2004.03601.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
(Midazolam is often used for premedication; it is known to promote vasodilation and may therefore affect redistribution of heat during surgery. We examined the effect of pre-operative administration of midazolam on the development of intra-operative hypothermia. Forty-five patients were randomly allocated to one of three groups to receive no premedication (Group C), IM midazolam 0.04 mg.kg(-1) (Group M1) or 0.08 mg.kg(-1) (Group M2) 30 min prior to anaesthesia. Sedation levels were assessed, and then general anaesthesia was induced and maintained using propofol and fentanyl. During surgery, core temperature, which was similar for the three groups prior to induction of anaesthesia, decreased significantly less in the midazolam groups M1 and M2 compared to the control group C. Patients who were more heavily sedated prior to induction of anaesthesia, had significantly lower core temperatures peri-operatively than those who were less sedated, and core temperatures in unpremedicated patients fell to significantly lower levels during surgery than those who were drowsy. We conclude that pre-operative administration of midazolam produces an effect on the development of peri-operative hypothermia. We found that moderate pre-operative sedation reduces the peri-operative heat loss, possibly by affecting core-to-peripheral heat distribution.
Collapse
Affiliation(s)
- K Toyota
- Department of Anaesthesia, Tottori Prefectural Central Hospital, 730 Ezu, Tottori City, 680-0901, Japan.
| | | | | | | | | |
Collapse
|
31
|
Echizenya M, Mishima K, Satoh K, Kusanagi H, Sekine A, Ohkubo T, Shimizu T, Hishikawa Y. Heat loss, sleepiness, and impaired performance after diazepam administration in humans. Neuropsychopharmacology 2003; 28:1198-206. [PMID: 12700718 DOI: 10.1038/sj.npp.1300160] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In spite of the accumulation of knowledge regarding the neuropharmacological action of benzodiazepines (Bz), the physiological process by which their sedative/hypnotic effects are induced remains poorly understood. We conducted a single-blind, crossover trial to evaluate the role of the thermoregulatory process in sleepiness and impaired psychomotor performance induced by a standard Bz, diazepam (DZP). Each of the eight healthy young male volunteers (mean age, 19.75 years; range, 18-23 years) was given a single oral dose of either 5 or 10 mg of DZP or placebo 12 h after his average sleep onset time. Changes in plasma DZP concentration, proximal body temperature (p-BT), distal body temperature (d-BT), subjective sleepiness measured by the Visual Analog Scale and Stanford Sleepiness Scale, and psychomotor performance measured by Choice Reaction Time were monitored under a modified constant routine condition in which various factors affecting thermoregulation, alertness, and psychomotor performances were strictly controlled. Orally administered DZP induced a significant transient decrease in p-BT and psychomotor performance as well as an increase in d-BT and subjective sleepiness. Distal-p-BT gradient (DPG; difference between d-BT and p-BT), which is an indicator of blood flow in distal skin regions, showed a strong positive correlation with the plasma DZP concentration, indicating that DZP in clinical doses promotes heat loss in a dose-dependent manner. The DPG also correlated positively with the magnitude of subjective sleepiness and impaired psychomotor performance. These findings indicate that the sedative/hypnotic effects of Bz could be due, at least in part, to changes in thermoregulation, especially in the process of heat loss, in humans.
Collapse
Affiliation(s)
- Masaru Echizenya
- Department of Neuropsychiatry, Akita University School of Medicine, Japan
| | | | | | | | | | | | | | | |
Collapse
|
32
|
Vanni SMD, Braz JRC, Módolo NSP, Amorim RB, Rodrigues GR. Preoperative combined with intraoperative skin-surface warming avoids hypothermia caused by general anesthesia and surgery. J Clin Anesth 2003; 15:119-25. [PMID: 12719051 DOI: 10.1016/s0952-8180(02)00512-3] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
STUDY OBJECTIVES To evaluate the effects of intraoperative skin-surface warming with and without 1 hour of preoperative warming, in preventing intraoperative hypothermia, and postoperative hypothermia, and shivering, and in offering good conditions to early tracheal extubation. DESIGN Prospective, randomized, blind study. SETTING Teaching hospital. PATIENTS 30 ASA physical status I and II female patients scheduled for elective abdominal surgery. INTERVENTIONS Patients received standard general anesthesia. In 10 patients, no special precautions were taken to avoid hypothermia. Ten patients were submitted to preoperative and intraoperative active warming. Ten patients were only warmed intraoperatively. MEASUREMENTS AND MAIN RESULTS Temperatures were recorded at 15-minute intervals. The patients who were warmed preoperatively and intraoperatively had core temperatures significantly more elevated than the other patients during the first two hours of anesthesia. All patients warmed intraoperatively were normothermic only at the end of the surgery. The majority of the patients warmed preoperatively and intraoperatively or intraoperatively only were extubated early, and none had shivering. In contrast, five unwarmed patients shivered. CONCLUSIONS One hour of preoperative warning combined with intraoperative skin-surface warming, not simply intraoperative warming alone, avoided hypothermia caused by general anesthesia during the first two hours of surgery. Both methods prevented postoperative hypothermia and shivering and offered good conditions for early tracheal extubation.
Collapse
Affiliation(s)
- Simone Maria D'Angelo Vanni
- Department of Anesthesiology, School of Medicine of the University of São Paulo State, Botucatu, São Paulo, Brazil.
| | | | | | | | | |
Collapse
|
33
|
Matsukawa T, Ozaki M, Nishiyama T, Imamura M, Iwamoto R, Iijima T, Kumazawa T. Atropine prevents midazolam-induced core hypothermia in elderly patients. J Clin Anesth 2001; 13:504-8. [PMID: 11704448 DOI: 10.1016/s0952-8180(01)00313-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
STUDY OBJECTIVE To test the hypothesis that core temperature is well preserved when atropine and midazolam are combined. DESIGN Randomized, blinded study. SETTING Department of Anesthesia, Yamanashi Medical University. PATIENTS 40 elderly, ASA physical status I and II patients (aged more than 60 years). INTERVENTIONS Patients were randomly assigned (n = 10 per group) to premedication with: 1) saline control; 2) midazolam 0.05 mg/kg; 3) atropine 0.01 mg/kg; and 4) midazolam 0.05 mg/kg combined with atropine 0.01 mg/kg. All premedication was given on the ward at approximately 8:30 am, approximately 30 minutes before induction of anesthesia. MEASUREMENTS AND MAIN RESULTS Core temperatures were measured at the right tympanic membrane. Mean skin temperature was calculated as 0.3 x (T(chest) + T(arm)) + 0.2 x (T(thigh) + T(calf)). Fingertip perfusion was evaluated using forearm minus fingertip and calf minus toe, skin-surface temperature gradients. Temperatures were evaluated at the time of premedication and 30 minutes later, just before induction of anesthesia. Core temperature remained nearly constant in the control patients (0.1 +/- 0.2 degrees C; mean +/- SD), whereas it decreased significantly in the patients given midazolam alone (-0.3 +/- 0.1 degrees C). Atropine alone increased core temperature (0.3 +/- 0.2 degrees C), although the increase was not statistically significant. The combination of midazolam and atropine attenuated the hypothermia induced by midazolam alone (0.0 +/- 0.2 degrees C). Initial skin-temperature gradients exceeded 0 degrees C in all groups, indicating that the patients were vasoconstricted. The gradients were unchanged by premedication with saline or atropine. Midazolam significantly decreased the gradient (-1.8 +/- 1.1 degrees C), as did the combination of midazolam and atropine (-1.4 +/- 0.9 degrees C). CONCLUSIONS The thermoregulatory effects of benzodiazepine receptor agonist and cholinergic inhibitors oppose each other, and the combination leaves core temperature unchanged.
Collapse
Affiliation(s)
- T Matsukawa
- Department of Anesthesia, Yamanashi Medical University, Yamanashi 49-3898, Japan.
| | | | | | | | | | | | | |
Collapse
|
34
|
Toyota K, Sakura S, Saito Y, Shido A, Matsukawa T. IM droperidol as premedication attenuates intraoperative hypothermia. Can J Anaesth 2001; 48:854-8. [PMID: 11606340 DOI: 10.1007/bf03017349] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
PURPOSE Perioperative hypothermia results largely from core-to-peripheral heat redistribution. Droperidol, which is often used for premedication, promotes vasodilation, and thus may affect redistribution of heat. Accordingly, we tested the hypothesis that preanesthetic droperidol would affect perioperative hypothermia. METHODS Twenty-three ASA physical status I patients scheduled for arthroscopic ligament reconstruction were randomly assigned to two groups to receive no premedication or im droperidol 0.1 mg x kg(-1) 30 min before anesthesia. Anesthesia was induced and maintained with propofol and fentanyl. We monitored core (tympanic) and peripheral (palm) temperatures, and skin (fingertip) blood flow for two hours after the induction of anesthesia during surgery. RESULTS Before the induction of anesthesia, patients given droperidol were more deeply sedated than those given no premedication. Core temperature, which was similar in both groups before induction, decreased significantly more in the control than in the droperidol patients (0.75 +/- 0.34 degrees C and 0.37 +/- 0.20 degrees C, respectively, at 75 min after induction; P <0.01). Preinduction peripheral temperature and skin blood flow were lower in the control group than in the droperidol group, but the two variables became similar in both groups after induction. CONCLUSION The results of the present study confirm our hypothesis that premedication with droperidol affects perioperative hypothermia. Droperidol may prevent core-to-peripheral heat redistribution after the induction of anesthesia.
Collapse
Affiliation(s)
- K Toyota
- Department of Anesthesiology, Shimane Medical University, Izumo City, Japan
| | | | | | | | | |
Collapse
|
35
|
Kasai T, Hirose M, Matsukawa T, Takamata A, Kimura M, Tanaka Y. Preoperative blood pressure and intraoperative hypothermia during lower abdominal surgery. Acta Anaesthesiol Scand 2001; 45:1028-31. [PMID: 11576056 DOI: 10.1034/j.1399-6576.2001.450817.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Preoperative factors including age and body habitus affect intraoperative hypothermia during general anesthesia. We hypothesized that preoperative blood pressure also plays a contributory role in the induction of intraoperative hypothermia. METHODS We evaluated the effect of preoperative systolic blood pressure (SBP) on core temperature during lower abdominal surgery under general anesthesia. In 36 female patients under 65 years of age, patients with a preoperative SBP of 140 mmHg or greater upon arrival in the operating theater were assigned to the high SBP group (n=18), while those with SBP below 140 mmHg were assigned to the normal SBP group (n=18). Anesthesia was maintained with isoflurane and nitrous oxide combined with epidural buprenorphine, and routine thermal care was provided intraoperatively. RESULTS There were no significant differences in age, height or weight between the two groups. Tympanic membrane temperature in the normal SBP group started to decrease significantly from 15 min after induction of anesthesia compared to that in the high SBP group, and continued to decrease further at two hours after induction. Vasoconstriction threshold, determined to be tympanic membrane temperature at the time when a forearm minus finger skin surface gradient exceeded 0 degrees C, was significantly higher in the high SBP group than in the normal SBP group. CONCLUSION These results suggest that preoperative SBP has some preventive effect on the decrease in intraoperative core temperature during lower abdominal surgery under general anesthesia.
Collapse
Affiliation(s)
- T Kasai
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | | | | | | | | | | |
Collapse
|
36
|
Thoresen M, Whitelaw A. Cardiovascular changes during mild therapeutic hypothermia and rewarming in infants with hypoxic-ischemic encephalopathy. Pediatrics 2000; 106:92-9. [PMID: 10878155 DOI: 10.1542/peds.106.1.92] [Citation(s) in RCA: 212] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Clinical trials of mild cooling to 35 degrees C or below in infants with early hypoxic-ischemic encephalopathy are under way. The objective of this study was to systematically document cardiovascular changes associated with mild therapeutic hypothermia and rewarming in such infants. PATIENTS AND METHODS Nine infants with gestational ages of 36 to 42 weeks, with 10-minute Apgar scores of 5 or less, clinical encephalopathy, and an abnormal electroencephalogram before 6 hours were cooled by surface cooling the trunk (n = 3) or by applying a cap perfused with cooled water (n = 6) for a median of 72 hours. The target core temperature was 34.0 degrees C to 35.0 degrees C for head-cooled infants and 33.0 degrees C to 34.0 degrees C for surface-cooled infants. Maintenance heating and rewarming were provided by an overhead heater. RESULTS Mean arterial blood pressure increased by a median of 10 mm Hg during cooling and fell by a median of 8 mm Hg on rewarming. Heart rate decreased by a median of 34 beats/minute on cooling and increased by a median of 32 beats/minute on rewarming. A large increase in the output of the overhead heater decreased mean arterial blood pressure in 5 infants. Anticonvulsant drugs, sedatives, or intercurrent hypoxemia also produced falls in temperature. The inspired oxygen fraction had to be increased by a median of.14 to maintain oxygenation during cooling with 2 infants requiring 100% oxygen, an effect probably attributable to pulmonary hypertension, which was reversible with rewarming. CONCLUSIONS Therapeutic cooling produces changes in heart rate and blood pressure that are not hazardous, but the combination of inadvertent overcooling and inappropriately rapid rewarming, together with sedative drugs that can impair normal thermoregulatory vasoconstriction, can cause hypotension in posthypoxic newborn infants. Infants who already require 50% oxygen should be cooled cautiously because pulmonary hypertension may develop. Knowledge of these cardiovascular changes, careful monitoring, anticipation, and correction should help to avoid potential adverse effects in the upcoming clinical trials.
Collapse
Affiliation(s)
- M Thoresen
- Division of Child Health, University of Bristol, England
| | | |
Collapse
|