[Perioperative thermal management]

[Influence of anesthesia on surgical site infections]

Surgical site infections (SSI) are the most frequent cause of impaired perioperative wound healing, lead to increased postoperative morbidity, mortality and length of hospital stay and are therefore a relevant perioperative complication. In addition to numerous measures taken by the surgical departments, there are anesthesiological options that can help to reduce the risk of SSI. In addition to heat, volume and transfusion management these include, for example, the use of antibiotics and the choice of the anesthesia procedure. This article is intended to provide fundamental knowledge on SSI, shows various options for reducing them in the context of anesthesia and evaluates their effectiveness and evidence based on the current state of knowledge.

Current understanding of thermo(dys)regulation in severe burn injury and the pathophysiological influence of hypermetabolism, adrenergic stress and hypothalamic regulation—a systematic review

Background

In this systematic review, we summarize the aetiology as well as the current knowledge regarding thermo(dys)regulation and hypothermia after severe burn trauma and aim to present key concepts of pathophysiology and treatment options. Severe burn injuries with >20% total body surface area (TBSA) affected commonly leave the patient requiring several surgical procedures, prolonged hospital stays and cause substantial changes to body composition and metabolism in the acute and long-term phase. Particularly in severely burned patients, the loss of intact skin and the dysregulation of peripheral and central thermoregulatory processes may lead to substantial complications.

Methods

A systematic and protocol-based search for suitable publications was conducted following the PRISMA guidelines. Articles were screened and included if deemed eligible. This encompasses animal-based in vivo studies as well as clinical studies examining the control-loops of thermoregulation and metabolic stability within burn patients

Results

Both experimental animal studies and clinical studies examining thermoregulation and metabolic functions within burn patients have produced a general understanding of core concepts which are, nonetheless, lacking in detail. We describe the wide range of pathophysiological alterations observed after severe burn trauma and highlight the association between thermoregulation and hypermetabolism as well as the interactions between nearly all organ systems. Lastly, the current clinical standards of mitigating the negative effects of thermodysregulation and hypothermia are summarized, as a comprehensive understanding and implementation of the key concepts is critical for patient survival and long-term well-being.

Conclusions

The available in vivo animal models have provided many insights into the interwoven pathophysiology of severe burn injury, especially concerning thermoregulation. We offer an outlook on concepts of altered central thermoregulation from non-burn research as potential areas of future research interest and aim to provide an overview of the clinical implications of temperature management in burn patients.

Anaesthetic management of cytoreductive surgery followed by hyperthermic intrathoracic chemotherapy perfusion

BACKGROUND

Macroscopic cytoreductive surgery and hyperthermic intrathoracic chemotherapy perfusion (HITHOC) is a new multimodal approach for selected patients with primary and secondary pleural tumors, which may provide the patient with better local tumor control and increased overall survival rate.

METHODS

We present a single-center study including 20 patients undergoing cytoreductive surgery and HITHOC between September 2008 and April 2013 at the University Medical Center Regensburg, Germany. Objective of the study was to describe the perioperative, anaesthetic management with special respect to pain and complication management.

RESULTS

Anaesthesia during this procedure is characterized by increased intrathoracic airway and central venous pressure, hemodynamic alterations and the risk of systemic hypo- and hyperthermia. Securing an adequate intravascular volume is one of the primary goals to prevent decreased cardiac output as well as pulmonary edema. Transfusion of packed red blood cells (PRBC) was necessary in seven of 20 (35%) patients. Only two patients (10%) showed an impairment of coagulation in postoperative laboratory analysis. Perioperative forced diuresis is recommended to prevent postoperative renal insufficiency. Supplementary thoracic epidural analgesia in 13 patients (65%) showed a significant reduction of post-operative pain compared with peroral administration of opioid and non-opioid analgesics.

CONCLUSION

This article summarizes important experiences of the anaesthesiological and intensive care management in patients undergoing HITHOC.

[Prewarming. Yesterday's luxury, today's minimum requirement]

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.

[Efficacy of a novel warming blanket: prospective randomized trial]

BACKGROUND

Perioperative hypothermia is a common complication of general anesthesia and occurs in up to 50 % of patients during ear, nose and throat (ENT) surgery. In this prospective, randomized controlled study the hypothesis that a new conductive warming blanket (Barrier® EasyWarm®, Mölnlycke Health Care Erkrath, Germany) is better in reducing the incidence of perioperative hypothermia in ENT surgery than insulation with a conventional hospital duvet alone was tested.

MATERIALS AND METHODS

After approval of the local ethics committee and written informed consent 80 patients with a planned procedure time between 1 and 3 h were recruited. Anesthesia was induced and maintained using propofol, remifentanil and rocuronium and the core temperature was measured using an esophageal temperature probe. Patients in the study group were warmed at least 30 min prior to induction of anesthesia using the novel warming blanket (Barrier® EasyWarm®) and patients in the control group were insulated with a standard hospital duvet. Data were tested using Fisher's exact test, Student's t-test or the Mann-Whitney U-test as appropriate. Time-dependent changes in core temperature were evaluated using repeated measures analysis of variance (ANOVA) and post hoc Scheffé's test. Results are expressed as mean ± SD or as median and interquartile range (IQR) as appropriate. A p < 0.05 was considered to be statistically significant.

RESULTS

The ANOVA did not identify a significantly higher core temperature in the study group at any time point. Furthermore, Fisher's exact test showed no differences in the incidence of intraoperative (12 out of 29 versus 10 out of 32 patients, p = 0.44) or postoperative hypothermia (12 out of 29 versus 9 out of 32 patients, p = 0.30) between the groups. No adverse effects were observed.

CONCLUSIONS

In the studied patient group the new conductive warming blanket (Barrier® EasyWarm®) showed no superiority compared to conventional thermal insulation alone.

[Anesthesia for geriatric patients. Part 1: age, organ function and typical diseases]

Due to demographic changes in the population of industrial nations the number of elderly patients undergoing elective or emergency procedures will rise significantly in the coming years. Anesthesia for geriatric patients is challenging for the anesthesiologist in many ways: with increasing age numerous physiological changes occur which all lead to a subsequent reduction of physical performance and compensatory capacity of the organism, in many cases additionally aggravated by chronic illness. Subsequently, these age-dependent changes (with or without chronic illness) increase the risk for admission to intensive care units, perioperative death, treatment costs and a prolonged length of hospital stay. Therefore, subtle preoperative assessment and tailored anesthetic management are essential in elderly patients. Part 1 of this continuous education article covers the influence of age on organ functions and describes typical comorbidities which are of high relevance for the perioperative care of geriatric patients. The special features of anesthetic agents and anesthesia management in the elderly will be presented in part 2.

Fast-Track-Rehabilitation am Beispiel der Kolonchirurgie

Fast-track rehabilitation refers to an interdisciplinary multimodal procedure to improve and accelerate recovery and avoid perioperative complications. The concept aims at reducing morbidity and discharging patients faster. It includes preoperative patient information, atraumatic surgical technique, stress reduction, pain therapy mostly via regional anesthetic techniques (frequently, thoracic epidural anesthesia), optimized fluid and temperature management, early enteral feeding, prophylaxis of gastrointestinal atony and postoperative nausea and vomiting, fast postoperative patient mobilization, and earlier hospital discharge. Fast-track protocols exist for all kind of surgical procedures but are best established for colon surgery.

Hypothermie in der Herzchirurgie

Since the beginning of the era of cardiac surgery hypothermia remains a mainstay in perioperative management. This role is increasingly being questioned because of many disadvantages and the lack of evidence of advantages. Using modern techniques of perfusion and myocardial protection as well as improved surgical techniques the results with normothermia seem to be comparable. The importance of hypothermia in present day cardiac surgery is discussed with respect to myocardial and cerebral protection.