**5.1 Pharmacology**

The reduction of hepatic and renal functions impacts pharmacokinetic and pharmacodynamic of anesthetic drugs. This might be increased the sensitivity to these drugs. In addition, the decrease in total body water leads to a reduction in the central compartment and increased serum concentration after a bolus administration of a drug. Minimal alveolar concentration declines with age. Geriatric patients are more sensitive to anesthetic agents and normally require smaller doses for the same clinical effect. Long-acting drugs would be continued through out the hospital stay. This effect of aging on pharmacokinetic depends upon the drug is used.

## **5.2 Nutrition**

Poor nutrition status is common in the geriatric patients. A meta-analysis presented that perioperative oral nutritional supplementation had a positive effect on serum total protein and led to fewer complications, but did not have a positive effect on postoperative mortality [7]. Prolonged preoperative fasting should be avoided in this population. The recent study has confirmed that preoperative complete geriatric assessment increases ability to predict patients at a greater risk for morbidity and mortality among the geriatric patients with advanced age or multiple comorbidities.

### **5.3 Musculoskeletal**

All types of degenerative diseases encompass the geriatric patients. This may limit exercise tolerance and makes it difficult to assess their fitness. Epidural and spinal blocks are technically difficult. In addition, the geriatric patients are susceptible to fractures and dislocation. Positioning and pressure points should be well taken before and during the procedure.

## **6. Preoperative preparation**

#### **6.1 Assessment**

Preoperative geriatric assessment includes functional physical status, neurocognitive function, systematic evaluation of comorbidities, substance abuse, frailty, nutrition, and medication. A complete history and clinical assessment as well as appropriate laboratory testing is required. However, preoperative evaluation of

geriatric patients characteristically is more complex than that of younger patients. Moreover, perioperative functional status could be difficult to evaluate. Aging results in the alterations in physiology that are linked to reduce the functional reserve and ability to compensate for the physiological stress.

Assessment of preoperative mental status is critical as it typically reflects on the postoperative cognitive status. Subsequently, the consumption of multiple medications so classic of the geriatric patients can change homeostatic mechanisms. All geriatric patients must have a preoperative anesthetic evaluation and preparation as well as relevant consultations. The geriatric patient is greater risk for long-term functional compromise after the stress of surgery than the younger patient. In general, geriatric patients with complex medical histories are best appreciated before the surgery to ensure that an appropriate preparation. Multidimensional assessments may help redefine standards for accomplishment of surgery [8].

#### **6.2 Preoperative testing**

Generally, routine preoperative testing of geriatric patients is not recommended unless coexisting medical sicknesses are identified or suspected. However, in the geriatric patients, our knowledge is somewhat more limited. Recent studies on routine preoperative testing in geriatric patients are observed. To date, it is not clear whether certain preoperative screening tests have a different profit in the geriatric age group. Routine screening in the geriatric patients does not significantly enhance information obtained from the patient's history. Generally, electrocardiogram is compulsory. A chest film would be decided for patients with acknowledged respiratory diseases and patients with symptomatic cardiorespiratory diseases.

According to guidelines of the American College of Cardiology and the American Heart Association for preoperative cardiac assessment, the patient's activity level is a primary element of the necessity for further evaluation [9]. Major predictors of cardiac risk are unstable coronary diseases, decompensated heart failure, significant arrhythmias and severe valvular disease. In patients with intermediate clinical predictors, the type of surgery and functional status of the patients will have major parts in defining the nature and magnitude of preoperative testing. However, no preoperative cardiovascular testing should be implemented if the results will not change perioperative management. In day case surgery, geriatric patients needed careful planning and proper preoperative assessment and preparation.

### **7. Anesthetic techniques**

The determination of the planned anesthetic technique for surgery in geriatric patients should occur in a multidisciplinary approach. Irrespective of the type of anesthetic techniques, anesthesia should be performed by experienced anesthesiologists who are qualified to accomplish the perioperative care of geriatric patients [10]. Generally, all anesthetic techniques may be applied. The choice of anesthesia is prejudiced by numerous factors such as the patient's medical condition, type and duration of surgery, as well as skill of anesthesiologist and surgeon. To date, there is inadequate evidence to support a single best anesthetic plan for geriatric patients. In a recent review, there might be benefits to selecting regional versus general anesthesia as a primary anesthetic modality in certain patient groups. However, this issue remains controversial due to the quality of the studies and the lack of consideration of the risks of neuraxial blockade in several reports [11, 12]. No differences were detected in postoperative morbidity and mortality, rate of readmission as well as

hospitalization costs in geriatric patients undergoing regional anesthesia or general anesthesia (GA) for hip surgery [13].
