Is Postanesthesia Care Unit Length of Stay: Increased in Hypothermic Patients?

Deconstructing delirium in the post anaesthesia care unit

The course of neuro-cognitive recovery following anaesthesia and surgery is distinctive and poorly understood. Our objective was to identify patterns of neuro-cognitive recovery of the domains routinely assessed for delirium diagnosis in the post anaesthesia care unit (PACU) and to compare them to the cognitive recovery patterns observed in other studies; thereby aiding in the identification of pathological (high risk) patterns of recovery in the PACU. We also compared which of the currently available tests (3D-CAM, CAM-ICU, and NuDESC) is the best to use in PACU. This was a post hoc secondary analysis of data from the Alpha Max study which involved 200 patients aged over 60 years, scheduled for elective surgery under general anaesthesia lasting more than 2 h. These patients were assessed for delirium at 30 min following arrival in the PACU, if they were adequately arousable (Richmond Agitation Sedation Score ≥ −2). All tests for delirium diagnosis (3D-CAM, CAM-ICU, and NuDESC) and the sub-domains assessed were compared to understand temporal recovery of neurocognitive domains. These data were also analysed to determine the best predictor of PACU delirium. We found the incidence of PACU delirium was 35% (3D-CAM). Individual cognitive domains were affected differently. Few individuals had vigilance deficits (6.5%, n = 10 CAM-ICU) or disorganized thinking (19% CAM-ICU, 27.5% 3D-CAM), in contrast attention deficits were common (72%, n = 144) and most of these patients (89.5%, n = 129) were not sedated (RASS ≥ −2). CAM-ICU (27%) and NuDESC (52.8%) detected fewer cases of PACU delirium compared to 3D-CAM. In conclusion, return of neurocognitive function is a stepwise process; Vigilance and Disorganized Thinking are the earliest cognitive functions to return to baseline and lingering deficits in these domains could indicate an abnormal cognitive recovery. Attention deficits are relatively common at 30 min in the PACU even in individuals who appear to be awake. The 3D CAM is a robust test to check for delirium in the PACU.

Nurses' Awareness and Practices of Unintentional Perioperative Hypothermia Prevention: A Cross-Sectional Study

Unintentional perioperative hypothermia can cause potentially life-threatening complications. The aim of this study was to determine the awareness and practices of nurses regarding unintentional perioperative hypothermia prevention. The study was conducted at a teaching hospital in Gambia with descriptive cross-sectional design. A total of 53 nurses voluntarily participated in this study. The questionnaire used in this study was developed based on the American periOperative Registered Nurses (AORN) and National Institute for Health and Care Excellence perioperative hypothermia guidelines. Descriptive statistics, Pearson correlation, Student t-test, and one-way ANOVA were used in the analysis of data. The result of the study showed that nurses had high level of awareness of unintentional perioperative hypothermia prevention; however, practice levels were found to be low. Based on the results of the study, development of policies, implementation of the unintentional perioperative hypothermia prevention guidelines, and continuous education to improve nurses' knowledge and practices were recommended.

Mean Temperature Loss During General Anesthesia for Laparoscopic Cholecystectomy: Comparison of Males and Females

Introduction

Mild hypothermia is common after general anesthesia. It is associated with discomfort and shivering. Greater fall of temperature is associated with more devastating complications. Data regarding the effect of gender on perioperative hypothermia is scanty.

Objectives of the study

To determine and compare mean core temperature loss in males and females undergoing laparoscopic cholecystectomy under general anesthesia.

Setting and design

Descriptive cross-sectional study in a tertiary care teaching hospital.

Subjects and methods

Ninety-seven elective laparoscopy patients were included through non-probability consecutive sampling. Intraoperatively, there was standardization of monitoring equipment, drapes, operation room temperature (21-22 °C), humidity (50%), irrigation fluid temperature (37 °C), peritoneal CO₂ temperature (21-22 °C), anesthetic fresh gas flow rates at induction and maintenance. Temperature recording equipment (nasopharyngeal probe) and temperature recording interval (10 minutes) were also standardized from induction till the end of surgery. Final temperature was recorded at the end of surgery before emergence.

Results

Mean temperature loss was 0.73 ⁰C ± 0.47⁰C. Mean loss was significant in males compared to females with a mean difference of 0.28°C ± 0.93⁰C; P-value= 0.003.

Conclusion

Mean temperature decreases significantly in laparoscopic cholecystectomy patients under general anesthesia. We recommend that more care is needed to prevent hypothermia in male patients because of their higher susceptibility to hypothermia.

The Effectiveness of Four Intervention Methods for Preventing Inadvertent Perioperative Hypothermia During Total Knee or Total Hip Arthroplasty

Inadvertent perioperative hypothermia (IPH) occurs when a patient experiences a core temperature below 36° C (96.8° F) in perioperative settings and is a preventable risk factor for anesthesia- and surgery-related complications. Forced-air warming is an effective method to maintain normothermia. This study compared four interventions for preventing IPH for 120 patients undergoing primary elective unilateral total knee or total hip arthroplasty. The study was based on a time series nonequivalent comparison group design to investigate whether the incidence of IPH differed among treatment groups. We also sought to determine whether the patients' preoperative perceptions of warmth or cold correlated with core body temperatures. Patients receiving convective warming and prewarming appeared to experience fewer IPH events than patients in the other study groups. This study suggests that hypothermia is a common issue for patients undergoing total knee or total hip arthroplasty and that it may be possible to reduce its frequency.

Impact of Intraoperative Hypothermia on Microsurgical Free Flap Reconstructions

BACKGROUND

 Patients requiring microsurgical defect reconstruction are highly susceptible to intraoperative hypothermia, given oftentimes long operative times and exposure of large skin surface areas. While the impact of hypothermia has been extensively studied across various surgical fields, its role in the setting of microsurgical free flap reconstruction remains elusive. This study evaluates the effects of hypothermia on outcomes of free flap reconstructions.

METHODS

 Within 7 years, 602 patients underwent 668 microvascular free flap reconstructions. The cases were divided into two groups regarding the minimal core body temperature during free flap surgery: hypothermia (HT; < 36.0°C) versus normothermia (NT; ≥36.0°C). The data were retrospectively screened for patients' demographics, perioperative details, flap survival, surgical complications, and outcomes.

RESULTS

 Our data revealed no significant difference with regard to the rate of major and minor surgical complications, or the rate of revision surgery between both groups (p > 0.05). However, patients in the HT group showed significantly higher rates of total flap loss (6.6% [HT] vs. 3.0% [NT], p < 0.05) and arterial thrombosis (4.6% [HT] vs. 1.9% [NT], p < 0.05). This translated into a significantly longer hospitalization of patients with reduced core body temperature (HT: mean 16.8 days vs. NT: mean 15.1 days; p < 0.05).

CONCLUSION

 Hypothermia increases the risk for arterial thrombosis and total flap loss. While free flap transfer is feasible also in hypothermic patients, surgeons' awareness of core body temperature should increase. Taken together, we suggest that the mean intraoperative minimum temperature should range between 36 and 36.5°C during free flap surgery as a pragmatic guideline.

The Nurse Anesthetists' Adherence to Swedish National Recommendations to Maintain Normothermia in Patients During Surgery

PURPOSE

The aim of this study was to determine if nurse anesthetists (NAs) have access, knowledge, and adhere to recommended guidelines to maintain normal body temperature during the perioperative period.

DESIGN

A descriptive survey design.

METHODS

Questionnaires were sent to heads of the department (n = 56) and NAs in the operating departments in Sweden.

FINDING

The level of access to the recommendations is high, but only one third of the operating departments have included the recommendations in their own local guidelines. The NAs' adherence was low, between 5% and 67%, and their knowledge levels were 57% to 60%.

CONCLUSIONS

A high level of knowledge, access, and adherence are important for the organization of operating departments to prevent barriers against implementation of new recommendations or guidelines. There are needs for education about patients' heat loss due to redistribution and clear recommendations.

Hipotermia no período intra-operatório: é possível evitá-la?

O estudo teve como objetivo identificar as medidas adotadas para a prevenção de hipotermia no período intra-operatório. Trata-se de um estudo com delineamento de pesquisa não experimental, tipo descritivo-exploratório, prospectivo. Para tal elaborou-se um instrumento de coleta de dados, o qual foi submetido à validação aparente e de conteúdo. A amostra foi constituída de 70 pacientes. A medida mais empregada na sala de operação foi o método passivo de aquecimento cutâneo como o uso de lençol de algodão (11,4%) e o enfaixamento dos membros inferiores (14,3%). A utilização de um método ativo de aquecimento cutâneo ocorreu uma única vez (1,4%). Os resultados evidenciados demonstraram a necessidade de implementação de intervenções eficazes para a prevenção da hipotermia e o enfermeiro tem papel importante neste contexto, uma vez que a segurança do paciente e a redução de complicações decorrentes do procedimento anestésico cirúrgico são metas do cuidado de enfermagem.

Outcome of a strategy to reduce surgical site infection in a tertiary-care hospital

BACKGROUND

Surgical site infection (SSI) is a preventable complication. Achieving a zero SSI rate for all clean operations should be the goal of all surgeons.

AIM

We aimed to reduce our SSI rate by 50% for patients undergoing elective gastrointestinal and hernia operations.

METHODS

The study was conducted in a tertiary-care hospital department of surgery from January 2006 to December 2007 for all clean and clean-contaminated elective gastrointestinal and hernia operations. Four interventions targeted at reducing SSI were implemented in January 2006: Use of clippers instead of shavers for surgical site hair removal; standardized prophylactic antibiotic regimen and antibiotic administration within 30 min before incision; standardized glucose monitoring for diabetics; and maintenance of postoperative normothermia. Prospective data were collected and compared with historical data from January to December 2005.

RESULTS

A total of 2,408 patients underwent elective gastrointestinal and hernia operations from January 2006 to December 2007. After implementation, we were able to achieve 91%, 87%, 89%, and 76% overall compliance with the respective interventions, but postoperative normothermia was achieved in only 44% of our patients. With the bundle of interventions, our overall SSI rate was reduced from 3.1% to 0.5% (p < 0.001), an 84% reduction within two years. The incidence of SSI was 1.7% in colorectal operations, 1.2% in upper gastrointestinal operations, 0.3% in hepatopancreaticobiliary operations, and zero in inguinal and ventral hernia operations. The estimated cost saving for both the patients and the hospital was S$208,562 (US$147,967).

CONCLUSIONS

Surgical site infections could be reduced with the bundle of interventions. With these encouraging results, the good practices should be sustained and promulgated. Such a SSI prevention program must be embedded in the work processes for all surgical disciplines.

Factors associated to the development of hypothermia in the intraoperative period

This study aimed to assess factors associated to body temperature changes intraoperatively in patients undergoing elective surgery. A prospective study including 70 patients was carried out in a charity hospital. A data collection instrument was developed and its face and content validity was established. The variables measured were operating room temperature and humidity and patient body temperature at different times. In the multivariate linear regression, the variables type of anesthesia, duration of anesthesia, body mass index, and operating room temperature were directly associated to mean body temperature. Nurses are responsible for planning and implementing effective interventions that can contribute to minimize costs and most importantly reduce hypothermia complications.

Hipotermia no período intra-operatório em pacientes submetidos a cirurgias eletivas

OBJETIVO: Analisar a temperatura corporal do paciente submetido a cirurgia eletiva no período intra-operatório. MÉTODOS: Para a coleta de dados elaborou-se um instrumento que foi submetido à validação aparente e de conteúdo e a amostra foi constituída de 70 pacientes. As variáveis mensuradas foram: temperatura e umidade da sala de cirurgia e temperatura corporal do paciente em diferentes momentos do período intra-operatório. RESULTADOS: Em relação à temperatura corporal dos pacientes observou-se que no final do procedimento anestésico-cirúrgico a média foi de 33,6º C. A temperatura média da sala na chegada dos pacientes foi de 24,6º C e na quarta hora de procedimento anestésico-cirúrgico foi de 22,4ºC. Houve correlação estatisticamente significante e positiva entre as variáveis mensuradas. CONCLUSÃO: Os resultados apontaram a necessidade de implementação de intervenções efetivas para a prevenção da hipotermia e, neste cenário, a atuação do enfermeiro é crucial para a melhoria da assistência prestada ao paciente cirúrgico.

Inadvertent hypothermia: a literature review

While working on my first placement in the operating department recovery room, I was surprised by the frequency of patients coming into recovery with mild hypothermia, having taken their temperature on arrival. In many cases the patient did not arrive with a forced-air warming blanket, or any device other than a cotton blanket. It seemed to me that it would be more efficient, kinder and possibly more cost-effective to takesteps to prevent perioperative hypothermia rather than to treat the consequences.

Hypothermia control in elderly surgical patients in the intraoperative period: evaluation of two nursing interventions

OBJECTIVES: To evaluate the efficacy of two different nursing interventions regarding control of body heat loss, using blankets during the intraoperative period of elderly patients. METHODS: This was an experimental, comparative, applied, longitudinal prospective study with a quantitative approach. Eighty-one elderly patients undergoing elective surgery with a surgical time frame of at least one hour were selected by systematic probability sampling into two Experimental and one Control Group. Informed consent was obtained from participants. Data was collected by biophysiological measurement, using a tympanic thermometer. RESULTS: After the homogeneity of variables - gender, surgical duration, age, BMR, anesthesia, room humidity and temperature, drugs and liquid infusion- had been demonstrated, the interventions were confronted. Incidence of hypothermia (59.3%) and body heat loss (E1=-0.6ºC , E2=-0.6oC and C=-0.7ºC) were not significantly different between the groups (p=0.85 and p=0.7 respectively). CONCLUSIONS: Results show the need for associated extra body warming methods to maintain normothermia.

A Team Approach to the Prevention of Unplanned Postoperative Hypothermia

Postoperative hypothermia (ie, a core temperature lower than 96.8 degrees F [36 degrees C]), is a problem frequently seen in surgical patients, especially those undergoing total joint replacement. Patients who experience hypothermia may have increased recovery times and postoperative complications. A team of clinical staff members and personnel from the performance improvement (PI) department of a hospital used a PI model to incorporate use of preoperative forced-air warming blankets that resulted in improved postoperative core temperatures.

Survey on intraoperative temperature management in Europe

BACKGROUND AND OBJECTIVES

Inadvertent perioperative hypothermia causes serious morbidity in surgical patients. However, recent reports suggest that patients might still be hypothermic after elective surgery. We thus surveyed intraoperative temperature monitoring and management practices in Europe.

METHODS

Postal survey of 801 representative hospitals from 17 European countries on the same day. The questions addressed the number of surgical procedures and type of anaesthesia performed, mode and site of temperature monitoring and method of patient warming. Mean and standard error of the mean or count and percentage were calculated. The t-test or contingency table analysis with the Fisher's exact test were used.

RESULTS

Eight thousand and eighty-three surgical procedures were assessed from 316 responding hospitals (39.4%). Overall, patient temperature monitored in 19.4% and 38.5% of the patients were actively warmed. Under general anaesthesia, body temperature was monitored in 25% and during regional anaesthesia in 6%, P = 0.0005. Nasopharyngeal temperature was most often taken under general anaesthesia, while tympanic temperature was preferred during regional anaesthesia. Under general anaesthesia, 43% of patients were actively warmed as compared to 28% with regional anaesthesia, P = 0.0005. Forced-air warming was the method of choice for both general and regional anaesthesia.

CONCLUSIONS

Intraoperative temperature monitoring is still uncommon and hence active patient warming is not a standard of care in Europe. Awareness of perioperative hypothermia is critical to its prevention, and thus temperature monitoring is a pre-requisite. The objective is to maintain normothermia in patients throughout surgery. A European practice guideline for perioperative patient temperature management is warranted.

Postoperative hypothermia—The chilling consequences

Unplanned hypothermia is commonly encountered in the perioperative period. Nursing has contributed to the literature on hypothermia with studies on shivering and treatment modalities; however, the direct physiological consequences of postoperative hypothermia have been reported mainly in the medical literature. Research on the physiological effects of postoperative hypothermia offers nurses further evidence to support interventions for temperature correction in patients with hypothermia. Evidence indicates that forced-air warming is the most effective method for warming hypothermic patients. The Roy Adaptation Model is explained as a framework for nursing care of patients with hypothermia. Clinical practice guidelines for unplanned perioperative hypothermia also are provided.